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R Santoro

Publications and source records attributed to R Santoro.

At least 37 records · Page 2Linked to original sources
PubMed2000

[The effects of remifentanil on hemodynamic response to intubation. A comparative study with fentanyl] .

BACKGROUND: The aim of this study was to evaluate the effects of remifentanil in comparison with those of fentanyl on the hemodynamic response to orotracheal intubation. METHODS EXPERIMENTAL DESIGN: prospective comparative and randomized study. SETTING: operating room in a neurosurgery department at University. PATIENTS: 50 patients, ASA I or II with age ranging from 32 to 64 years were divided in two groups randomly. INTERVENTIONS: 25 patients received fentanyl as single bolus dose of 2.0 micrograms/kg and atropine 0.01 mg/kg i.v. as premedication while the remainders received atropine 0.01 mg/kg i.v. and remifentanil 0.2 microgram/kg/min as infusion. All patients were induced with propofol 2.0 mg/kg and cisatracurium 0.15 mg/kg for muscle relaxation and were intubated 4 min after induction of anesthesia. MEASUREMENTS: Heart rate, SAP, DAP, MAP and RPP were recorded at different times: baseline, induction, intubation, 1, 2, 3 and 4 min after intubation; ECG and pulsoximetry were monitored continuously. Statistical analysis was carried out using ANOVA for repeated measures and Bonferroni t-test a value of p < 0.05 was considered to be significant. RESULTS: Significant increases in PAS were recorded, at intubation and at 1 min after in patients treated with fentanyl; in the remifentanil group significant decreases in SAP at induction and at 4 min after intubation were recorded. HR increased significantly at intubation and at 1, 2 and 3 min after in the fentanyl group. RPP showed a significant decrease at induction in the remifentanil group and significant increases at intubation and at 1, 2 and 3 min after in patients treated with fentanyl. CONCLUSION: In conclusion remifentanil was found to properly control the hemodynamic response to intubation in comparison with fentanyl.

Adult↗
PubMed1999

UV-Laser induced protein/DNA crosslinking reveals sequence variations of DNA elements bound by c-Jun in vivo.

Many proteins involved in the modulation of gene expression exert their function through direct interaction with DNA. The sequence specificity of these interactions provides the basis for many regulatory mechanisms. The sites that are utilized by a transcription factor are usually analyzed using in vitro binding studies. To detect true in vivo binding sites we developed a method, presented here, that allows construction of recognition element DNA (reDNA) libraries which represent in vivo binding sites plus flanking sequences. reDNA libraries can be constructed for any well-characterized transcription factor. Here we used this method for an in vivo study of genomic DNA elements that interact with the transcription factor c-Jun in rat cerebellum.

Animals↗
PubMed1999

[Klatskin tumor. A study of 15 resected cases].

STUDY AIM: Klatskin tumors are rare. Prognosis is still poor, and long term survival can be expected only after surgery, which is the treatment of choice. The aim of this study is to report the results of 15 resected cases and, by analysis of the literature, to emphasize the progress of the surgical treatment in hilar cholangiocarcinoma. PATIENTS AND METHODS: Between 1990 and 1998, 27 patients affected by Klatskin tumor were observed. Eight women and seven men underwent surgical resection. The mean age was 59 years. Thirteen patients (48%) had curative resection (7 hilar resection (HR), 5 HR combined with partial hepatectomy (PH) and 1 HR + PH with portal vein resection). Two patients had palliative resection and surgical drainage. RESULTS: One in-hospital death occurred right after hepatectomy with portal vein resection (6.6%). Postoperative morbidity was 40%. Patients were regularly followed. Ten patients died and 5 were alive at the time of this study. The 1, 2 and 3-year survival after a curative resection was 84%, 54% and 34%. The median survival was 28.5 months. Lymph node involvement did not show a statistically significant difference on median survival between the positive group and the negative group (26.2 vs 29.8 months) because of the small number of patients. Survival after hilar resection at 1, 2, 3, and 5 years was 100%, 57.1%, 28.6% and 0%. Four out of the 6 patients who underwent hilar resection combined with partial hepatectomy were still alive 1, 23, 29, 38 months after resection. Hepatectomy increased mortality (16% vs 0%). Palliative biliary resection and surgical drainage were successfully performed in 2 patients. CONCLUSION: Aggressive surgical treatment of Klatskin tumor can improve the survival of patients. Careful pre-operative management has to be carried out by a multidisciplinary approach including surgeons, hepatologists, radiologists and pathologists. Hepatic resection including the caudate lobe is often performed in order to obtain microscopic tumor-free margins and curative resection (R0). Biliary drainage and treatment of cholangitis is mandatory before surgery in order to improve the surgical outcome. Surgical treatment is characterized by high technical difficulties, and better results can be achieved by hepatobiliary surgical teams.

Adult↗
PubMed1998

Loss of FHIT expression in gastric carcinoma.

Loss of heterozygosity involving the short arm of chromosome 3 has been reported in gastric and other human tumors. We have cloned and mapped a candidate tumor suppressor gene, FHIT (fragile histidine triad), to this chromosomal region (3p14.2). To investigate the role of FHIT gene alterations in the development of gastric carcinoma, we examined 8 gastric carcinoma-derived cell lines and 32 primary adenocarcinoma samples by Southern blot analysis. We also analyzed the integrity of FHIT transcripts by reverse transcription-PCR. The occurrence of alterations in the FHIT gene and its transcript correlated with the absence of Fhit protein expression by immunoblot analysis in the cancer cell lines. Four of eight cell lines showed deletion or rearrangement within the FHIT gene, together with the absence of the wild-type transcript and the Fhit protein. Among the primary gastric carcinomas, rearrangement of the FHIT gene and/or aberrant reverse transcription-PCR products were detected in 17 of 32 (53%) tumors, and 20 of 30 (67%) samples exhibited an absence of Fhit protein expression. Gastric cancer is thought to develop from carcinogenic exposure, possibly explaining the high frequency of abnormalities in the FHIT gene, a fragile locus exhibiting susceptibility to carcinogen-induced alterations. The consequent absence or reduction of Fhit protein expression is consistent with the proposal that the FHIT gene is a preferential target of environmental carcinogens and that FHIT inactivation plays a role in the development of gastric cancer.

Acid Anhydride Hydrolases↗
PubMed1998

[Port site metastasis. Prospective study of 131 cases].

Laparoscopic staging and laparoscopic treatment of gastrointestinal malignancy is still controversial because some studies report port sites metastases. The aim of the study is to determine in 131 patients, with prospective follow-up, after laparoscopic staging or laparoscopic treatment, the incidence of port site metastases. 131 patients with localized a gastrointestinal malignancy or other advanced malignant tumors were included. In 57 cases only laparoscopic staging was performed, in 25 cases the laparoscopic staging was followed by a laparoscopic resection and in 49 cases after laparoscopic staging a traditional laparotomic treatment was performed. In 57 cases (43.5%) the tumor invaded the serosal layer. The median follow-up was 17.7 months (3 to 62 months). 502 port-sites were controlled. One patients (0.7%) presented one port site metastases after right colectomy for carcinoma with local carcinomatosis. This study confirm that port sites metastases are rare, and that are favorised by serosal invasion and support the laparoscopic staging of malignant abdominal tumors in order to recognize occult lesions which are not detected by conventional preoperative clinical, biological and radiological explorations (44.2% in this study). In addition, selected patients can be submitted to laparoscopic treatment of the disease (20%).

Adult↗
PubMed1998

Gastric cancer. Clinico-biological updating and analysis of 400 operated cases.

Gastric cancer is a rather common disease worldwide. In Italy it still accounts for 15,000 deaths annually. A sharp drop in the incidence rate of Lauren's intestinal histotype has been reported, whereas the frequency of the diffuse histotype is relatively steady. If the histogenesis of the latter is still somewhat obscure, the intestinal type confirms the sequence: atrophic gastritis--intestinal metaplasia--dysplasia--neoplasia. These different stages of development can nowadays be singled out through a series of indicators, the most reliable of which are the pepsinogen I/pepsinogen II ratio, the presence of sulphomucins and Lewis antigens in the gastric juices and NOR (Nucleolar Organizer Regions), cell ploidy and oncogenes determination. The genes involved in the neoplastic transformation are mostly oncosuppressors, the most frequent alterations being those relative to the APC gene, p53 and c-myc. In addition to the by now indispensable pathological staging of the disease, the modern prognostic factors are arising great interest: the most significant are the immunohistochemical examination of the peritoneal washing, and cell ploidy. Surgery is still the only potentially curative treatment: the earlier surgery is performed in the course of disease, the greatest the curative potential. The Authors' experience, which includes 400 operated cases with complete follow-up records, is here reported. The resectability rate turned out to be 84%, overall operative mortality was 6.5% with that due to surgical causes along being 3.7%. Overall survival at 5 years was 36%, while that of the curative operations 47%. Good results were obtained with the association surgery + intraoperative radiotherapy which resulted in a significant decrease in local recurrences of the disease.

Adenocarcinoma↗
PubMed1998

[A case of microcystic cystadenoma treated by duodenum preserving pancreatic head resection].

Cystic neoplasms of the pancreas constitute about 9% of all cystic lesions of the pancreas and less than 1% of all pancreatic neoplasms. The case of a 70 years-old woman with microcystic cystadenoma is reported. CT-scan of the abdomen diagnosed a 5 cm multilocular septated cyst, with calcifications in the context, localized in the head-uncinate process of the pancreas. The mass was well separated by a sharp cleavage plane with portal vein and superior mesenteric vessels. An ERCP showed cephalic symmetrical stenosis (diameter 3 mm) of the main pancreatic duct (MPD), mildly dilated in the remaining tract (diameter 6 mm). An intraoperative biopsy of the cystic wall was performed. Therefore, it was decided to proceed with a duodenum-preserving resection of the head of the pancreas (DPPHR), including the stenosis tract of the MPD in the surgical specimen. The reconstructive procedure consisted, by i.v. jejunal loop transposition, in a side-to-side pancreatico-jejunostomy, including in the anastomosis both corpocaudal stump and the resection cavity of the pancreatic head, and an end-to-side Roux-en-Y jejuno-jejunostomy. With respect to long-lasting pain relief and preservation of the endocrine and exocrine functions of the pancreas, DPPHR is a highly effective surgical procedure with a low early and late morbidity and mortality due to limited surgical resection. This technique, introduced into surgical practice by Beger, is indicated in patients with chronic pancreatitis with an inflammatory mass in the head of the pancreas. The authors conclude that this procedure can be performed also in case of pancreatic benign tumors, as microcystic cystadenoma. Advantages of this technique makes DPPHR an attractive alternative to Pylorus-Preserving-Pancreatico-Duodenectomy (PPPD).

Aged↗
PubMed1997

Multiple neurinomas of the parapharyngeal space.

The authors describe a rare case of three neurinomas arising in the parapharyngeal space. In spite of the large extension of the neoplasms, the only symptom reported by the patient was some dysphagia. Magnetic resonance imaging allowed us to identify the three masses and suppose their diagnosis. The therapeutic approach used is also reported.

Adult↗
PubMed1997

Comparison of integrin alpha chain expression in benign and malignant salivary gland tumors.

OBJECTIVE: This study investigates the distribution of the alpha chain of the integrin family of extracellular matrix receptors in a series of adenomas and carcinomas of salivary gland origin to determine if the malignant phenotype is associated with modification of the expression of these receptors. STUDY DESIGN: Cryostat sections of 36 tumor specimens were stained by a standard streptavidin-biotin-peroxidase technique using primary monoclonal antibodies against alpha 1-6 and alpha v integrin chains. The immunohistochemical reaction was scored using a three-point scale and the results were analyzed using Fisher's exact test. RESULTS: In salivary adenomas, alpha 2, alpha 3, alpha 4, alpha 6, and alpha v chains were widely expressed in most of the cases studied. The alpha 1 subunit was prominently expressed by the epithelial cells of Warthin's tumor, whereas a minority of pleomorphic adenomas showed immunoreactivity for this antigen. We observed alpha 5 subunit expression only in the mesenchymal-like component of pleomorphic adenomas. In salivary carcinomas, integrin alpha chain expression was heterogeneous, varying greatly between different histotypes and within the same histotype. The distribution of the antigens was similar to that of adenomas, except for the alpha 6 chain, which localized not only at the interface between cell and matrix, but also at sites of cell-cell contact. When the immunohistochemical levels of integrin alpha chain expression were compared in adenomas and carcinomas, expression significantly decreased for the alpha 6 and alpha v chains (p = 0.0007; p = 0.002, respectively). CONCLUSIONS: Loss of alpha 6 and alpha v integrin subunits occurring in salivary gland carcinomas could modify the adhesive properties of malignant cells, contributing to the invasive potential of these tumors.

Adenocarcinoma↗
PubMed1997

Transmission of parvovirus B19 by coagulation factor concentrates exposed to 100 degrees C heat after lyophilization.

BACKGROUND: Double inactivation by solvent/detergent treatment plus heating at 100 degrees C for 30 minutes after lyophilization has been adopted to improve viral safety of factor VIII and factor IX concentrates, particularly with respect to non-lipid-enveloped viruses. The aim of this study was to evaluate the safety of concentrates exposed to these virucidal methods. STUDY DESIGN AND METHODS: Twenty-six previously untreated hemophiliacs, 19 with factor VIII deficiency and 7 with factor IX deficiency, were investigated in a prospective multicenter study over a 12-month follow-up period by the use of serologic and virologic markers for lipid- and non-lipid-enveloped viruses (human immunodeficiency virus types 1 and 2; hepatitis A, B, and C viruses; B19 parvovirus antibodies; and B19 DNA). Overall, 270,000 U of factor VIII and 102,000 U of factor IX concentrate were administered during the study period. RESULTS: None of the 26 patients seroconverted for human immunodeficiency virus or hepatitis C virus. Hepatitis B virus markers remained negative in the 10 unvaccinated hemophiliacs. No hepatitis A virus seroconversion occurred among 17 susceptible patients. B19 seroconversion (IgM) and B19 viremia were observed within 2 weeks of the first concentrate infusion in 8 of 15 susceptible patients, 5 of 11 treated with factor VIII and 3 of 4 with factor IX concentrate. CONCLUSION: This prospective study indicates that very high temperatures applied to lyophilized concentrates appear to prevent the transmission of hepatitis A virus to hemophiliacs. However, B19 parvovirus still contaminates concentrates despite the use of this robust virucidal method.

Adolescent↗
PubMed1996

Increased mutagen-induced chromosome damage in patients with transformed laryngeal pre-cancerosis.

Factors that contribute to malignant transformation of laryngeal pre-neoplastic lesions remain largely unknown. Potential etiological factors may be related to a genetically controlled sensitivity to environmental carcinogens. In this study, we investigated bleomycin-induced chromosome damage in 15 patients who experienced a malignant transformation of preneoplastic laryngeal lesions during follow-up, as compared with chromosome fragility in 30 historical controls with no progression of keratoses during a 10-year follow-up, in a match-paired analysis. Chromosomal analysis demonstrated higher sensitivity to clastogens in patients with malignant progression of laryngeal pre-neoplastic lesions than that of control patients with no evolution of their original laryngeal keratoses (p = 0.003). Furthermore, among the study patients, chromosome sensitivity was most apparent in non-tobacco users with malignant transformation of laryngeal disease. Our data suggest that subjects with pre-neoplastic laryngeal lesion showing increased susceptibility to carcinogens could be at higher risk for development of laryngeal carcinoma.

Adult↗
PubMed1996

H1-H1 cross-linking efficiency depends on genomic DNA methylation.

Oligonucleosomal DNA preparations from condensed-inactive chromatin were examined, before and after artificial methylation by bacterial SssI methylase, for their ability to allow cooperative H1-H1 interactions under conditions of different ionic strength. Our results support the conclusion that, within the highly methylated genomic DNA, there are some CpG's whose unmethylated state is critical for chromatin folding. Circular dichroism spectra indicate that artificial overmethylation of native oligonucleosomal DNA reduces its efficiency in inducing an ordered conformation of H1 histone. Temperature melting profiles confirm on the other hand that the native and the artificially overmethylated forms of oligonucleosomal DNA are both able to bind H1 histone.

Circular Dichroism↗
PubMed1996

Specific inhibitory effect of H1e histone somatic variant on in vitro DNA-methylation process.

H1e and H1c histone variants were purified from mouse L929 fibroblasts using a reverse phase HPLC, and their effect on in vitro DNA methylation was investigated, together with their ability to bind unmethylated or methylated CpG-rich 44bp oligonucleotides. In a "physiological" range of H1:DNA ratios only H1e, at variance from H1c, was found to cause a marked inhibition of in vitro enzymic DNA methylation. It was also shown that both variants have a similar affinity in binding a methylated CpG-rich oligonucleotide, but that the binding to the same oligonucleotide in the unmethylated form occurs preferentially with H1e rather than with H1c. H1e is therefore likely to be directly involved in maintaining CpG-rich sequences in the unmethylated state.

Animals↗
PubMed1996

Linkage analysis identifies gene carriers among members of families with hereditary nonpolyposis colorectal cancer.

BACKGROUND & AIMS: Uncertainty about genetic risk in hereditary nonpolyposis colorectal cancer (HNPCC) may lead to unnecessary screening. The aims of this study were to show how gene linkage findings can elucidate who is at risk and requires intensive screening and how cancer control can be enhanced by screening high-risk family members. This information can be useful given the public health magnitude of HNPCC. METHODS: An extended family with HNPCC was studied using formal linkage analysis with DNA extraction from blood samples, followed by genotyping with polymerase chain reaction technique for microsatellite markers. Sixty-one blood relatives of a family with HNPCC, 5 of whom had colorectal cancer, and 12 unrelated family members underwent DNA sampling for genetic analysis. RESULTS: Linkage analysis showed that all 5 affected individuals had a haplotype with the same alleles 10/7/9, which was also detected in 13 first-degree healthy gene carriers and absent in the remaining 43 non-gene carriers. In the asymptomatic subjects screened, one incidental colorectal cancer and four adenomas were detected in 3 of 6 gene carriers. An adenoma was found in 1 of 17 noncarriers; the remaining 16 noncarriers have undergone 67 unnecessary colonoscopies. CONCLUSIONS: Linkage analysis can differentiate gene carriers from non carriers. Colorectal cancer screening should be restricted to gene carriers.

Adolescent↗
PubMed1995

Does hypomethylation of linker DNA play a role in chromatin condensation.

The inhibitory effect that H1 histone exerts on the in vitro DNA methylation process, catalysed by mammalian DNA methyltransferase, together with the relative hypomethylation of linker DNA in eukaryotic cells chromatin, suggest that this hypomethylated state of linker DNA can be of importance in allowing or regulating H1-dependent chromatin condensation. In native oligonucleosomes (olnu), i.e., in chromatin fragments consisting of 5-20 nucleosomes each, there was a correlation between the effects of H1 on the DNA ellipticity at 280 nm and the in vitro assayed methyl-accepting ability. The same was true in H1-depleted or in H1-reconstituted preparations. Artificial methylation caused olnu DNA to lose its ability to allow cooperative H1-H1 interactions under ionic strength conditions similar to those known to affect the transition of the 10-nm filament to the 30-nm chromatin fiber. These results suggest that hypomethylation of linker DNA plays a role in the H1-H1 interactions that are needed for solenoid condensation.

Animals↗
PubMed1995

Specific variants of H1 histone regulate CpG methylation in eukaryotic DNA.

Upon HPLC fractionation of human placenta or calf thymus H1 histone preparations, only some fractions enriched in the H1e-c variants were able to exert a severe inhibition on in vitro enzymatic DNA methylation. These fractions, though similar to the other variants in interacting with genomic DNA, were also the only ones which could bind CpG-rich ds-oligodeoxyribonucleotides (oligos). Both the 6-CpG ds-oligo and the DNA purified from chromatin fractions enriched in 'CpG islands' were good competitors for the binding of H1e-c to the 6meCpG ds-oligo. This ability to bind any DNA sequence and to suppress the enzymatic methylation in any sequence containing CpG dinucleotides suggests, for these particular H1 variants, a possible role in maintaining CpG island DNA and linker DNA at low methylation levels.

Animals↗