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D D'Amico

Publications and source records attributed to D D'Amico.

At least 19 recordsLinked to original sources
PubMed1992

Polymorphic sites within the MCC and APC loci reveal very frequent loss of heterozygosity in human small cell lung cancer.

Using single-strand conformation polymorphism we have found two polymorphic sites, AAC to AAT at codon 511 (exon 12) and GCT to GCG at codon 708 (exon 15), in the MCC gene. These sites and an RsaI polymorphic site in APC allowed us to study 23 human small cell lung cancer (SCLC) and 7 non-small cell lung cancer samples for allele loss. Of the 23 SCLC samples, 21 (91%) were informative for one or more of these markers, and we found allele loss in more than 80% (17 of 21). In non-small cell lung cancer samples, 5 of 7 (71%) were informative, and reduction or loss of one allele was found in 2 of 5 (40%). Seven cases were informative for both genes, loss of heterozygosity occurred for both genes in five, one retained heterozygosity for both, and one SCLC had loss of heterozygosity for APC but not for MCC. We conclude that loss of heterozygosity occurs frequently for MCC and APC in lung cancer of all histological types and is very frequent in SCLC. This suggests the presence of tumor suppressor gene(s) in the MCC/APC region of 5q21 involved in human lung cancer.

Base Sequence↗
PubMed1992

Dexamethasone suppression test, melatonin and TRH-test in cluster headache.

The origin of Cluster Headache (CH) is still unknown. The periodicty and presence of symptoms due to both sympathetic and parasympathetic activity suggest the involvement of central nervous system structures, particularly the hypothalamus. To investigate hypothalamic involvement in CH, we employed a neuroendocrinological approach. We observed a normal dexamethasone suppression test (DST) in all patients, increased cortisol plasma levels in remission patients at 8.00am before and at the end of the DST, while only in CH patients during cluster period did we find a reduced TSH response to TRH and a reduced night-time melatonin peak. The neuroendocrinological derangements found in CH may be consistent with hypothalamic involvement.

Adult↗
PubMed1992

Beta-endorphin concentrations in the peripheral blood mononuclear cells of migraine and tension-type headache patients.

Levels of beta-endorphin in peripheral blood mononuclear cells have been studied as a new approach to investigating opioid tone in migraine and tension-type headache. Sixty-one patients with migraine without aura, 39 with migraine with aura and 23 with episodic tension-type headache were compared with 37 healthy controls. Peripheral blood samples were taken from patients not enduring headache attacks and not undergoing prophylactic treatment. A significant reduction in peripheral blood mononuclear cell beta-endorphin concentrations was observed in migraine patients with and without aura, but not in tension-type headache patients. Altered transmitter modulation to peripheral blood mononuclear cells may be the cause of this alteration, which could be part of a more diffuse opioid system derangement in migraine subjects.

Adult↗
PubMed1992

Absence of hereditary p53 mutations in 10 familial leukemia pedigrees.

Germline p53 mutations have been identified in the Li-Fraumeni syndrome but the role of such mutations in familial leukemia is not established. The p53 gene was examined by single-strand conformation polymorphism analysis of exons 4-8 in 10 families with multiple members affected with leukemia. The diagnoses included acute and chronic leukemias and Hodgkin's disease. Identified in two families were p53 mutations that were nonhereditary. These included a 2-bp deletion in exon 6 found in the lymphoblast DNA of one child whose sibling, cousin, and several adult relatives had acute leukemia. The other nonhereditary p53 mutation was a transition at codon 248 (CGG to CAG, arginine to glutamine) found in the lymphoblasts of a patient with a preleukemic syndrome and acute lymphoblastic leukemia (ALL) whose brother is a long-term survivor of ALL. Thus, p53 mutations were found to occur in two families but both were nonhereditary. Moreover, in the remaining eight families no p53 mutation was identified in the regions of p53 where most mutations have been found in other cancers. Although p53 mutations sometimes may be present, they do not appear to be a primary event responsible for hereditary susceptibility to familial leukemia. This study suggests involvement of other genes or mechanisms.

DNA, Neoplasm↗
PubMed1992

p53 gene mutations in non-small-cell lung cancer cell lines and their correlation with the presence of ras mutations and clinical features.

We screened 77 non-small-cell lung cancer (NSCLC) cell lines for mutations of the p53 gene using a single-strand conformation polymorphism (SSCP) assay. We found that 57 cell lines (74%) had mutations of the p53 gene. Three cell lines had a deletion of the p53 gene. Of the remaining 54 cell lines, 49 cell lines were sequenced and 52 mutations were confirmed. In contrast to previously published p53 mutations in other human tumors, the p53 gene mutations in NSCLC were diverse with regard to the location and nature of the mutations. The region corresponding to codons 144-166, which is outside the evolutionarily conserved regions, was a frequent site of p53 gene mutations in NSCLC. The presence of a p53 gene mutation was not associated with age, sex, histological types, culture site, treatment intent, presence of prior cytotoxic treatment, neuroendocrine differentiation, median culture time or patient survival. The prevalence of p53 mutations in cell lines with ras mutations did not differ from that in cell lines without ras mutations. However, p53 gene mutations in NSCLC cell lines with ras mutations tended to cluster in exon 8, suggesting the presence of a functional domain of the p53 gene relating to interaction with the ras gene. We conclude that p53 and ras mutations are frequent and apparently independent genetic alterations which play different roles in the pathogenesis, progression and prognosis of NSCLC.

Amino Acid Sequence↗
PubMed1992

High frequency of somatically acquired p53 mutations in small-cell lung cancer cell lines and tumors.

We analysed the p53 open reading frame (ORF) in 16 small-cell lung cancer (SCLC) cell lines by direct sequencing of cDNA/PCR products and in 20 SCLC tumors by chemical cleavage and single-strand conformation polymorphism analyses of genomic DNA/PCR products. Abnormalities of p53 were found in 16/16 cell lines (100%) and in 16/20 tumors (80%). In the SCLC cell lines, mutations (59% missense, 18% nonsense and 23% splicing) changing the coding sequence were dispersed between amino acids 68 and 342. In the tumor samples, while the mutations occurred predominantly in exons 5-8, other mutations were located outside these regions. G to T transversions were common, occurring in 32% of the cases. We found no p53 mutations in the corresponding normal tissue from 19 patients whose tumors had p53 lesions, indicating that the mutations were all somatically acquired. In analysing the clinical data of the patients we found no correlation between tumor response to therapy or survival and the location or type of mutations. We conclude from these data that: (1) p53 mutations are found in SCLC with high frequency; (2) p53 mutations in a significant fraction of cases generate cDNAs with nonsense or splicing mutations; and (3) to date, these mutations have all been somatically acquired events.

Base Sequence↗
PubMed1992

Expression of mutant p53 proteins in lung cancer correlates with the class of p53 gene mutation.

We investigated the immunocytochemical staining and immunoblotting characteristics of 33 different p53 mutant proteins identified in lung cancer cell lines (18 small-cell lung cancer and 15 non-small-cell lung cancer) using monoclonal antibodies pAbs 240, 421 and 1801. The p53 mutants studied were representative of those found in lung cancer and included three deletions, four nonsense, seven splicing and 19 missense lesions. Control cell lines included six B-lymphoblastoid cell lines and two lung cancer cell lines without p53 mutations. Immunocytochemistry demonstrated 16 cell lines (48%) with definite overexpression of p53 protein (the high-expresser group of mutants), while in the remainder of cases either no p53 expression or low levels of p53 protein expression were found (the low-expresser group of mutants). The type of p53 mutation correlated with the expresser group. High expressers all had p53 missense mutations in exons 5-8, and immunocytochemistry identified 16/17 (94%) of these mutants. Several classes of p53 mutations occur in the low-expresser groups: deletions, splicing mutants, nonsense mutants and missense mutations outside of exons 5-8 all resulted in very low or undetectable levels of p53 protein. We conclude that there are low- and high-expression groups of p53 mutants in lung cancer and that the detection of protein expression in tumor cells by immunocytochemistry and immunoblotting is dependent upon the type of mutation of the p53 tumor-suppressor gene.

Blotting, Western↗
PubMed1991

Steric course of the N-methylation in the biosynthesis of ergot alkaloids by Claviceps purpurea.

Using the chiral methyl group methodology, the methylation step in the biosynthesis of ergot alkaloids catalyzed by the enzyme AdoMet:dimethylallyltryptophan N-methyltransferase was found to proceed with net inversion of methyl group configuration. The enzyme thus conforms to the majority of methyltransferases studied which mediate a direct SN2 transfer of the methyl group from AdoMet to the acceptor nucleophile in a ternary enzyme substrate complex.

Claviceps↗
PubMed1991

Genetic transmission of migraine without aura: a study of 68 families.

68 randomly selected patients with migraine without aura (M) and 4 generations of their relatives (N = 394) were studied in order to probe the genetic hypothesis of migraine. Significantly more of the probands were women and M was significantly more frequent among female relatives. Earlier onset was commoner among male probands. A genetic component of M is indicated by the very high frequency of at least one affected relative (85.3%) and by a disease prevalence that is similar among both first and second degree relatives. A simple autosomal mode of transmission seems unlikely from analysis of the data on the affected relatives, while a "sex-limited" transmission mode is suggested.

Adult↗
PubMed1991

Effect of indomethacin on the kinetics of tumour necrosis factor alpha release and tumour necrosis factor alpha gene expression by human blood monocytes.

In this investigation we have examined the effects of indomethacin, an inhibitor of the cyclooxygenase pathway of arachidonic acid, upon the kinetics of the release of tumour necrosis factor alpha (TNF) and of the expression of TNF gene by lipopolysaccharide (LPS)-stimulated human blood monocytes (BM). Following stimulation of BM with LPS, TNF was released within 2 h, reached peak values at 8 h and declined at subsequent time-points (24 and 48 h). Indomethacin (10(-5) M) slightly stimulated the production of TNF at 2, 4, and 8 h and prevented the decline of TNF observed at 24 and 48 h. This effect was related to the persistence of TNF synthesis, as demonstrated by kinetic evaluation of the expression of TNF gene performed by dot-blot analysis. The effects of indomethacin on TNF release and TNF gene expression were due to the inhibition of endogenous prostaglandin (PG)E2 production. In the absence of indomethacin, PGE2 release by the LPS-stimulated BM began concomitantly with the decline of TNF production by the same cells under the same stimulus. Indomethacin completely blocked PGE2 release at any time-point. Exogenous PGE2 suppressed the release of TNF and the expression of TNF gene in a dose-dependent fashion. Exogenous PGE2 completely reversed the effects of indomethacin on TNF production at 24 h. These findings suggest that indomethacin may significantly alter the kinetics of TNF release and TNF gene expression by LPS-stimulated BM. These effects are related, at least in part, to the inhibition of the production of endogenous PGE2, an important self-driven regulatory factor of the kinetics of TNF production.

Dinoprostone↗
PubMed1991

Cluster-like headache and a median intracranial calcified lesion: case report.

A 69 year old man complaining of a cluster-like headache is reported. CT scan showed a median intracranial calcified lesion. Two main considerations are: 1) the importance of searching for an underlying structural lesion in patients with an "atypical" cluster headache; 2) the possible significance of a lesion localized close to the midline structures in the pathogenesis of cluster headache.

Aged↗
PubMed1991

Current situation in the treatment of gallbladder cancer. Considerations on the utility of an extended resection.

Twenty-two of the 25 patients with carcinoma of the gallbladder seen during the last 9 years have been analyzed for survival in relation to treatment and disease stage. All patients were classified according to Nevin's staging scheme, and a correct preoperative diagnosis was made in 31.8% of cases. The median survival of the 8 stage V patients who had no surgery or alternatively underwent only limited excision of the tumor was 16.5 days (for the two patients receiving explorative laparotomy); 2 months for a patient undergoing a debulking operation and 5 months for the 5 patients receiving nonoperative biliary drainage. Survival in patients undergoing cholecystectomy, whether associated with biliary drainage or not has proved to be adversely affected by the stage of the malignancy, the stage I patient being alive and well at 2 years whereas the stage II patient died after 5 and a half months, the stage III patient survived 1 year and the stage IV patient 1 year and 6 months. Stage V patients receiving simple cholecystectomy (1 case) or associated with biliary drainage (5 cases) died 16.5 days and 4.5 months following surgery, respectively. More radical operations have been performed in 4 other stage V patients, who had resection of segments IV and V (2 patients, one of them survived 3 months and the other is still alive and well at 5 months), resection of segment IV (survival was 15 days), and right hepatectomy (survival 7 months). In view of our limited experience no statistically significant conclusions can be drawn.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1990

Epidural spinal meningioma. Role of magnetic resonance in differential diagnosis.

A rare case of an extradurally growing spinal meningioma in an elderly woman is reported. Neuro-imaging, particularly magnetic resonance (MR), allowed to recognize the lesion, which, otherwise, could raise problems of differential diagnosis with a spinal metastasis. An emergency operation, required by a sudden neurological deterioration, was decisive in recovery of neurological deficits. In a review of the literature, extradurally growing spinal meningiomas appear to occur with a higher frequency than it is thought. Therefore, they are to be suspected when dealing with extradural spinal lesions.

Aged↗
PubMed1990

A chemical mismatch cleavage method useful for the detection of point mutations in the p53 gene in lung cancer.

Point mutations in genes can be etiologic of pulmonary diseases, as in the case of the inherited disorders alpha-1-antitrypsin deficiency and cystic fibrosis or in the context of dominant and recessive oncogenes in lung cancer. Various methodologies have been developed to screen for single-base mutations. These techniques include direct DNA sequencing, RNase protection, denaturing gradient gel electrophoresis, and chemical mismatch cleavage. The latter method offers the advantages of rapid and efficient analysis of genomic or cDNA and is thus ideally suited to screening applications. Furthermore, all possible single-base changes can theoretically be detected. In the present work, chemical mismatch cleavage was utilized to detect mutations in the p53 gene in small cell and non-small cell lung cancer. This technique was modified by using a two-step, hemi-nested PCR procedure for preparation of target genomic DNAs permitting an expanded target size for analysis. Evaluation by chemical mismatch cleavage of eight p53 cDNAs derived from lung tumors shown to have different mutations by DNA sequencing correctly detected the presence of a point mutation in all instances. Analysis of six additional tumor genomic DNAs with defined mutations in the corresponding p53 cDNAs accurately confirmed the mutation at the level of the genome. The technique also identified codon 72 and intron 6 polymorphisms. Using the intron 6 polymorphism, loss of heterozygosity at the p53 locus in tumor DNA was readily detected by chemical mismatch cleavage. Finally, utilizing this technique for scanning analysis of the p53 gene of uncharacterized lung tumor DNAs, additional mutations were identified in a prospective manner which were confirmed by sequence analysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗
PubMed1990

Identification of intronic point mutations as an alternative mechanism for p53 inactivation in lung cancer.

The p53 gene initially was thought to be an oncogene, but recent evidence suggests that wild-type p53 can function as a tumor suppressor gene in lung, colon, and breast cancer as well as less common malignancies. This study reports the first identification of intronic point mutations as a mechanism for inactivation of the p53 tumor suppressor gene. Abnormally sized p53 mRNAs found in a small cell and a non-small cell lung cancer cell line were characterized by sequence analysis of cDNA/PCR products, the RNase protection assay and immunoprecipitation. These mRNAs were found to represent aberrant splicing leading to the production of abnormal or no p53 protein. Sequence analysis of genomic DNA revealed that a point mutation at the splice acceptor site in the third intron or the splice donor site in the seventh intron accounts for the abnormal mRNA splicing. In one patient the same intronic point mutation was found in the tumor cell line derived from a bone marrow metastasis and in multiple liver metastases but not in normal DNA, indicating that it occurred as a somatic event before the development of these metastases. These findings further support the role of inactivation of the p53 gene in the pathogenesis of lung cancer and indicate the role of intronic point mutation in this process.

Amino Acid Sequence↗