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Biomedical subjects

M De Santis

Publications and source records attributed to M De Santis.

At least 37 records · Page 2Linked to original sources
PubMed2002

Ovine fetal growth curves in twin pregnancy: ultrasonographic assessment.

PURPOSE OF INVESTIGATION: The fetal-lamb model is a fundamental tool for developing clinical applications for the treatment of human fetal pathology (e.g., open fetal surgery). Accurate estimation of gestational age is important to avoid size-related problems during surgery. METHODS: To evaluate the effect of twinning on ovine fetal growth, we followed seven twin pregnancies in Comiso ewes from mating through parturition. Fetal growth indexes (muzzle-occipital and mean abdominal diameters, abdominal circumference, femoral and humeral length) were measured weekly using perimammary ultrasonography and analyzed with a linear quadratic regression model based on natural logarithms of each parameter and fetal age. RESULTS: The model explained > 90% of the variability observed, with determination coefficients of 95% (femoral length, abdominal circumference), 94% (abdominal diameter, humeral length), and 89% (muzzle-occipital diameter). CONCLUSION: Mean birth weight was lower than that reported for singleton fetal lambs, as it is in bigeminal pregnancies in humans, despite the uterine and placental differences between these two species. With the exception of slightly earlier growth deceleration, curves for head and long-bone growth resembled those for singleton ovine fetuses. Ovine fetal growth patterns (like those of humans) in singleton and twin pregnancies are similar.

Abdomen↗
PubMed2002

Complementary therapy for severe Rh-alloimmunization.

PURPOSE OF INVESTIGATION: This report describes successful treatment, using invasive and noninvasive techniques, of a 36-year-old woman (gravida 10, para 0) referred to our center at 13 weeks' gestation for severe Rh alloimmunization. Pre-pregnancy indirect Coombs titers ranged from 1:1024-2048. All nine past pregnancies (conceived with three different partners) had ended in abortion, intrauterine death or neonatal death METHODS: The patient was treated with a single session of plasmapheresis (week 14) immediately followed by five days of immunoglobulin therapy and immunosuppressive therapy based on azathioprine and prednisone (weeks 15-22). Seven fetal transfusions (one intraperitoneal, six intravascular) were performed beginning at 16 weeks. RESULTS: The pregnancy, which was characterized by insulin-dependent gestational diabetes, spontaneously resolving polyhydramnios and peak indirect Coombs titers of 1:65,536, ended at 27 weeks with cesarean section delivery of a viable female weighing 1,000 g. In spite of numerous neonatal complications, the child is physically well at age 3, with normal intellectual and psychomotor development. CONCLUSION: In light of the negative outcomes of the patient's nine past pregnancies, our experience suggests that the early initiation of an integrated approach based on noninvasive and invasive techniques can play a potentially decisive role in the management of severe Rh-alloimmunization.

Adult↗
PubMed2001

Predictive impact of 2-18fluoro-2-deoxy-D-glucose positron emission tomography for residual postchemotherapy masses in patients with bulky seminoma.

PURPOSE: To establish the predictive potential of 2-18fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) for detecting viable tumor tissue in residual postchemotherapy masses of seminoma patients. PATIENTS AND METHODS: In this prospective multicenter trial, results of FDG PET studies in seminoma patients with postchemotherapy masses > or = 1 cm were correlated with either the histology of the resected lesion or the clinical outcome on follow-up without resection. Negative PET scans of residual lesions that were devoid of viable tumor tissue on resection or disappeared, shrunk, or remained stable in size for at least 2 years were rated as true-negative (TN). Positive scans without histologic or clinical evidence of tumor tissue were classified as false-positive. In patients with histologically positive or progressive lesions, positive PET scans were defined as true-positive (TP) and negative scans, false-negative (FN). RESULTS: Thirty-seven PET scans of 33 patients were assessable at a median follow-up time of 23 months (range, 2 to 46 months). Histologic data were available from nine patients who had undergone resection. Twenty-eight patients were followed-up clinically and radiologically. Twenty-eight scans were TN, eight were TP, and one was FN. All 14 residual lesions more than 3 cm and 22 (96%) of the 23 < or = 3 cm were correctly predicted by FDG PET. The specificity (100%; 95% confidence interval [CI], 87.7% to 100%), sensitivity (89%; 95% CI, 51.7% to 99.7%), positive predictive value (100%), and the negative predictive value (97%) of FDG PET were superior to data obtained by assessing residual tumor size (< or = or > 3 cm). CONCLUSION: FDG PET is a clinically useful predictor of viable tumor in postchemotherapy residuals of pure seminoma, especially those greater than 3 cm.

Adult↗
PubMed2001

Regulation of heparin-binding EGF-like growth factor expression in Ha-ras transformed human mammary epithelial cells.

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) mRNA and protein expression is induced by EGF in MCF-10A nontransformed and Ha-ras transfected human mammary epithelial cells. The anti-EGF receptor (EGFR) blocking monoclonal antibody (MAb) 225 and the EGFR tyrosine kinase inhibitor PD153035 were able to inhibit the induction of HB-EGF mRNA levels in MCF-10A cells. However, the Ha-ras transformed MCF-10A cells were more refractory to inhibition by these agents and only a combination of the 225 MAb and PD153035 was able to significantly abrogate HB-EGF induction by EGF. The anti-erbB2 MAb L26 which interferes with heterodimer formation was able to block HB-EGF induction in response to EGF in MCF-10A cells and in the Ha-ras transformed cells only when used in combination with either the 225 MAb or PD153035. The MEK inhibitor PD90859 completely blocked EGF induction of HB-EGF mRNA levels in the nontransformed and Ha-ras transformed MCF-10A cells, which indicates that MAPK is involved in the signaling pathway of HB-EGF induction by EGF. An increase in the levels of HB-EGF may, therefore, be an important contributor to oncogenic transformation that is caused by Ha-ras overexpression in mammary epithelial cells. J. Cell. Physiol. 186:233-242, 2001. Published 2001 Wiley-Liss, Inc.

Antibodies, Monoclonal↗
PubMed2001

Preoperative chemoradiation with raltitrexed ('Tomudex') for T2/N+ and T3/N+ rectal cancers: a phase I study.

The use of raltitrexed ('Tomudex') as concomitant chemotherapy during preoperative radiotherapy in chemonaïve patients with stage II/III rectal cancer has been examined in this study and its recommended dose in conjunction with radiotherapy investigated. Forty-five Gray (Gy) of radiotherapy (1.8 Gy daily, 5 days per week) was delivered to the posterior pelvis, followed by a 5.4 Gy boost. Single doses of raltitrexed (2.0, 2.5 and 3.0 mg/m(2)) were administered on days 1, 19 and 38. Only 1 of the 15 patients entered experienced a dose limiting toxicity (DLT) (grade 3 leucopenia) at the 3.0 mg/m(2) dose level. The overall response rate was 80% (five complete responses, seven partial responses). These preliminary data suggest that raltitrexed is a well tolerated and effective treatment when combined with preoperative radiotherapy in patients with stage II/III rectal cancer. The recommended dose of raltitrexed for future phase II studies will be 3.0 mg/m(2).

Adenocarcinoma↗
PubMed2001

Update of the follow-up of mortality and cancer incidence among European workers employed in the vinyl chloride industry.

Although vinyl chloride is an established cause of liver angiosarcoma, the evidence is inconclusive on whether it also causes other neoplastic and nonneoplastic chronic liver diseases as well as neoplasms in other organs. Furthermore, the shape of the dose-response relation for angiosarcoma is uncertain. We have extended for approximately 8 years the mortality and cancer incidence follow-up of 12,700 male workers in the vinyl chloride industry in four European countries. All-cause mortality was lower than expected, whereas cancer mortality was close to expected. A total of 53 deaths from primary liver cancer (standardized mortality ratio 2.40, 95% confidence interval = 1.80-3.14) and 18 incident cases of liver cancer were identified, including 37 angiosarcomas, 10 hepatocellular carcinomas, and 24 liver cancers of other and unknown histology. In Poisson regression analyses we observed a marked exposure response for all liver cancers, angiosarcoma, and hepatocellular carcinoma. The exposure-response trend estimated for liver cancer in analyses restricted to cohort members with cumulative exposures of <1,500 parts per million-years was close to that estimated for the full cohort (relative risk of 2.0 per logarithmic unit of cumulative dose). No strong relation was observed between cumulative vinyl chloride exposure and other cancers. Although cirrhosis mortality was decreased overall, there was a trend with cumulative exposure.

Carcinogens↗
PubMed2001

Drug-induced congenital defects: strategies to reduce the incidence.

Approximately 1% of congenital anomalies relate to pharmacological exposure and are. in theory, preventable. Prevention consists of controlled administration of drugs known to have teratogenic properties (e.g. retinoids, thalidomide). When possible, prevention could take the form of the use of alternative pharmacological therapies during the pre-conception period for certain specific pathologies, selecting the most appropriate agent for use during pregnancy [e.g. haloperidol or a tricyclic antidepressant instead of lithium; anticonvulsant drug monotherapy in place of multitherapy; propylthiouracil instead of thiamazole (methimazole)], and substitution with the most suitable therapy during pregnancy (e.g. insulin in place of oral antidiabetics; heparin in place of oral anticoagulants; alpha-methyldopa instead of ACE inhibitors). Another strategy is the administration of drugs during pregnancy taking into account the pharmacological effects in relation to the gestation period (e.g. avoidance of chemotherapy during the first trimester, avoidance of nonsteroidal anti-inflammatory drugs in the third trimester, and avoidance of high doses of benzodiazepines in the period imminent to prepartum).

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2000

RAS transformation causes sustained activation of epidermal growth factor receptor and elevation of mitogen-activated protein kinase in human mammary epithelial cells.

Activation of the ras oncogene is an important step in carcinogenesis. Human MCF-10A mammary epithelial cells were transformed with a point-mutated form of the Ha-ras oncogene. Epidermal growth factor receptor (EGFR) phosphorylation levels were chronically elevated after EGF induction and the EGFR ligand-driven internalization rate was slower in Ha-ras transformed MCF-10A cells. Additionally, basal levels of p42/44 mitogen-activated protein kinase (MAPK) expression and enzyme activity were significantly higher in Ha-ras transformed cells, localized predominantly in the nucleus. The anti-EGFR monoclonal antibody (MAb) 225 and the EGFR tyrosine kinase inhibitor PD153035 blocked anchorage-independent growth of Ha-ras transformed cells in soft agar and were more effective when used in combination. The MEK inhibitor PD98059 and anti-erbB-2 MAb L26 also suppressed colony formation of Ha-ras transformed cells in soft agar. Therefore, Ha-ras transformation leads to an augmentation in signaling through the EGFR as a result of an increase in ligand-dependent phosphorylation, a decrease in its internalization and an up-regulation in basal p44/42 MAPK levels. These effects may contribute to uncontrolled growth of Ha-ras-transformed human mammary epithelial cells.

Antibodies, Monoclonal↗
PubMed2000

Acute recurrent polyhydramnios and amniotic prolactin.

A 25 year-old patient in her third pregnancy presented with acute polyhydramnios at 24 weeks' gestation, which was the same time as in the two previous pregnancies. In both she had preterm premature rupture of membranes, preterm delivery and neonatal deaths. In the third pregnancy, amnioreductions combined with medical treatment resulted in the birth by Caesarean section of a normally formed live male at 31 weeks of pregnancy. Acute recurrent polyhydramnios is an extremely rare condition of unknown aetiology. We hypothesized that amniotic prolactin plays a role in this pathology. It was measured serially in amniotic fluid and high levels were found.

Acute Disease↗
PubMed2000

Preoperative embolization in surgical treatment of mediastinal hemangiopericytoma.

The case of a 47-year-old man with a tumor of the posterosuperior mediastinum is reported. Surgical biopsy sample revealed a hemangiopericytoma, but radical excision was impossible because of massive bleeding. Percutaneous embolization of mediastinal tumor was performed to reduce peroperative blood loss. It allowed uneventful complete removal of the lesion. We recommend preoperative embolization in cases of hypervascular mediastinal tumors.

Embolization, Therapeutic↗
PubMed2000

Metastatic breast cancer in pregnancy: first case of chemotherapy with docetaxel.

The focus of this paper is a case study of a woman in the first trimester of pregnancy who presented with metastatic breast cancer. The bony spread of the metastases was rapid and it was necessary to treat the patient as soon as possible after the period of organogenesis (days 18-60 of human gestation). This stage is the phase of greatest sensitivity of teratogens and the malformations are observed most often. Yet, the choice of third-line chemotherapy was difficult because of anthracycline-resistant metastatic breast cancer. The world literature reported cytotoxic combinated regimens as the standard of care for the management of the metastases. The development of new antitumoral strategies with less toxicity and their encouraging results led us to the approval of docetaxel for the treatment of the patient even though it had never been tested in pregnancy. Docetaxel is a potent inhibitor of microtubule depolymerization and has a unique ability to alter certain classes of microtubules. The monochemotherapy was administered once every 3 weeks for a total of three cycles until 30 weeks of gestation. During the 32nd week of pregnancy the patient delivered a female infant whose birthweight and Apgar score were normal. The infant did not have any anomalies. The woman finished her treatment in puerperium and she received three cycles of docetaxel. The patient has been receiving vinorelbine (one cycle every 2 weeks) for 2 years; her last follow-up was good and showed that the progression of the metastases had stopped. The daughter's psychophysical development was normal.

Adult↗
PubMed2000

Natural history of inoperable hepatocellular carcinoma: estrogen receptors' status in the tumor is the strongest prognostic factor for survival.

Clinical course in hepatocellular carcinoma may be very different. We prospectively evaluated 96 patients with hepatocellular carcinoma unsuitable for radical therapy to investigate factors that could influence survival. Clinical, pathologic, and molecular data of patients were analyzed by univariate and multivariate analysis. The overall actuarial probability of survival at year 1, 2, 3, 4, 5, and 6 was 72%, 41%, 38%, 24%, 20%, and 9%. At univariate analysis, alpha-fetoprotein (AFP) (P =.0082); alkaline phosphatase (P =.0281); bilirubin (P =.0076); etiology (P =.0001); increment of tumor mass at month 3 (P =.0051); type of estrogen receptor (ER) in the tumor (P =.0000); prothrombin time (P =.0003); and portal vein thrombosis (P =.0000) had prognostic significance. At multivariate analysis, only type of ER (P =.0000) and bilirubin (P =.0030) showed independent predictive value for mortality. Survival was significantly longer in patients with wild-type estrogen receptors (P =.0000). Cumulative probability of survival at year 1, 2, 3, 4, 5, and 6 was 94%, 66%, 52%, 43%, 35%, and 18% for wild-type and 51%, 21%, 16%, and 9% for variant estrogen receptors (no patients alive after 4 years). Hepatitis B surface antigen (HBsAg)-positive patients with variant ERs had a median survival of 8 months versus 45 months in anti-hepatitis C virus-positive patients with wild-type ERs (P =.0001). In conclusion, (1) the presence of variant liver ER transcripts in the tumor was the strongest negative predictor of survival in inoperable hepatocellular carcinoma; (2) their presence was associated with spontaneous survival significantly worse than in patients with wild-type estrogen receptors; and (3) HBsAg-positive patients with variant receptors were characterized by the worst survival.

Aged↗
PubMed2000

The EGF-CFC family: novel epidermal growth factor-related proteins in development and cancer.

The EGF-CFC gene family encodes a group of structurally related proteins that serve as important competence factors during early embryogenesis in Xenopus, zebrafish, mice and humans. This multigene family consists of Xenopus FRL-1, zebrafish one-eyed-pinhead (oep), mouse cripto (Cr-1) and cryptic, and human cripto (CR-1) and criptin. FRL-1, oep and mouse cripto are essential for the formation of mesoderm and endoderm and for correct establishment of the anterior/posterior axis. In addition, oep and cryptic are important for the establishment of left-right (L/R) asymmetry. In zebrafish, there is strong genetic evidence that oep functions as an obligatory co-factor for the correct signaling of a transforming growth factor-beta (TGFbeta)-related gene, nodal, during gastrulation and during L/R asymmetry development. Expression of Cr-1 and cryptic is extinguished in the embryo after day 8 of gestation except for the developing heart where Cr-1 expression is necessary for myocardial development. In the mouse, cryptic is not expressed in adult tissues whereas Cr-1 is expressed at a low level in several different tissues including the mammary gland. In the mammary gland, expression of Cr-1 in the ductal epithelial cells increases during pregnancy and lactation and immunoreactive and biologically active Cr-1 protein can be detected in human milk. Overexpression of Cr-1 in mouse mammary epithelial cells can facilitate their in vitro transformation and in vivo these Cr-1-transduced cells produce ductal hyperplasias in the mammary gland. Recombinant mouse or human cripto can enhance cell motility and branching morphogenesis in mammary epithelial cells and in some human tumor cells. These effects are accompanied by an epithelial-mesenchymal transition which is associated with a decrease in beta-catenin function and an increase in vimentin expression. Expression of cripto is increased several-fold in human colon, gastric, pancreatic and lung carcinomas and in a variety of different types of mouse and human breast carcinomas. More importantly, this increase can first be detected in premalignant lesions in some of these tissues. Although a specific receptor for the EGF-CFC proteins has not yet been identified, oep depends upon an activin-type RIIB and RIB receptor system that functions through Smad-2. Mouse and human cripto have been shown to activate a ras/raf/MAP kinase signaling pathway in mammary epithelial cells. Activation of phosphatidylinositol 3-kinase and Akt are also important for the ability of CR-1 to stimulate cell migration and to block lactogenic hormone-induced expression of beta-casein and whey acidic protein. In mammary epithelial cells, part of these responses may depend on the ability of CR-1 to transactivate erb B-4 and/or fibroblast growth factor receptor 1 through an src-like tyrosine kinase.

Amino Acid Sequence↗