Biomedical subjects
A Ferraro
Publications and source records attributed to A Ferraro.
Binding of the protein disulfide isomerase isoform ERp60 to the nuclear matrix-associated regions of DNA.
Protein ERp60, previously found in the internal nuclear matrix in chicken liver nuclei, is a member of the protein disulfide isomerase family. It binds DNA and double helical polynucleotides in vitro with a preferential recognition toward the matrix-associated regions of DNA and poly(dA) x poly(dT), and its binding is inhibited by distamycin. ERp60 can be cross-linked chemically to DNA in the intact nuclei, suggesting that its association with DNA is present in vivo. As a whole, these results indicate that ERp60 is a component of the subset of nuclear matrix proteins that are responsible for the attachment of DNA to the nuclear matrix and for the formation of DNA loops. A distinctive feature of this protein, which has two thioredoxin-like sites, is that its affinity to poly(dA) x poly(dT) is strongly dependent on its redox state. Only its oxidized form, in fact, does it bind poly(dA) x poly(dT). The hypothesis can be made that through the intervention of ERp60, the redox state of the nucleus influences the formation or the stability of some selected nuclear matrix-DNA interactions.
Cross-linked telomere-protein complexes from chicken erythrocyte nuclei: isolation by a new procedure.
DNA-protein cross-linkages were produced in intact nuclei of chicken erythrocytes by the action of cis-diammine dichloroplatinum. The telomeric DNA-protein cross-linked complexes were then isolated by hybridization with a biotinylated oligonucleotide and selective binding on immobilized streptavidin. Two main nonhistone proteins were present in the purified complexes, migrating in SDS-gel electrophoresis with apparent molecular masses of 66 and 58 kDa, respectively. Although the identity of these two proteins is still unknown, it is significant that two proteins with similar electrophoretic behavior have been described as constituents of the human telomeric complexes. This procedure could also be applied to the isolation of DNA-protein cross-linked complexes containing any chosen DNA sequence.
Impaired adaptation of cardiopulmonary receptors to Western diet in normotensive black immigrants.
A blood pressure increase was reported in black immigrants from Africa to Western countries. The present study was undertaken to evaluate whether an impairment of the cardiopulmonary reflex might make blacks unable to adapt peripheral vascular resistance to increased sodium intake. Ten normotensive clinically healthy blacks (aged 38+/-6 years) who had recently migrated from Mogadishu, Somalia to Florence and 10 age- and gender-matched healthy white subjects were investigated. Cardiopulmonary baroreceptor reflex was studied after 7 days of normal (108 mEq) and low (30 mEq) sodium intake by assessing forearm vascular resistance (FVR) and central venous pressure (CVP) during the application of lower body negative pressure (LBNP) at -10 and -20 mm Hg. With a normal sodium diet the gain in cardiopulmonary baroreceptor reflex, expressed as the FVR increase per mm Hg of CVP reduction, was significantly lower in blacks than in white subjects (2.6+/-1.1 v 5.1+/-1.1 U per mm Hg of CVP, P < .001). Differences between the groups disappeared with a low-sodium diet because the reduction of the efficiency of the cardiopulmonary baroreceptor reflex was lower in blacks than in whites (2.4+/-0.7 v 3.3+/-0.7 U per mm Hg of CVP, P = .09). In conclusion, the efficiency of the cardiopulmonary reflex is lower in normotensive black immigrants than in whites. The lower adaptation of the cardiovascular system to the Western sodium diet could contribute to reported long-term blood pressure increase.
Secondary tumors in bone sarcomas after treatment with chemotherapy.
New oncologic treatments have improved survival in osteosarcoma and Ewing's sarcoma. However, these treatments may cause secondary malignancies after radiotherapy. This study evaluated the incidence of secondary malignancies after neoadjuvant chemotherapy. Between April 1972 and December 1990, 518 osteosarcoma and 299 Ewing's sarcoma patients entered neoadjuvant chemotherapy protocols. Follow-up records of all patients were analyzed and malignant tumors were reported. Nine patients developed another malignancy, including 5 leukemias, 1 astrocytoma, 1 liposarcoma, 1 parotid, and 1 breast carcinoma. Four leukemias were found in patients treated for osteosarcoma with chemotherapy, but not radiotherapy. Only one leukemia developed after Ewing's sarcoma treated with chemotherapy and radiotherapy. The incidence of leukemias is high, while the other tumors can be explained as unrelated cases. Incidence densities for leukemia were calculated for both groups of patients. Treated osteosarcoma patients seem to have a predisposition to develop leukemias, but whether this is chemotherapy induced needs to be investigated.
Phase I-II study of gemcitabine and carboplatin in stage IIIB-IV non-small-cell lung cancer.
PURPOSE: Platinum-based chemotherapy currently represents standard treatment for advanced non-small-cell lung cancer. Gemcitabine is one of the most interesting agents currently in use in advanced non-small-cell lung cancer, and high response rates have been reported when it is administered in combination with cisplatin. The aim of the present study was to evaluate the combination of gemcitabine and carboplatin in a phase I-II study. PATIENTS AND METHODS: Chemotherapy-naive patients with stage IIIB-IV non-small-cell lung cancer received carboplatin at area under the concentration-time curve (AUC) 5 mg/mL/min and gemcitabine at an initial dose of 800 mg/m2, subsequently escalated by 100 mg/m2 per step. Gemcitabine was administered on days 1 and 8 and carboplatin on day 8 of the 28-day cycle. Dose escalation proceeded up to dose-limiting toxicity (DLT), which was defined as grade 4 neutropenia or thrombocytopenia or grade 3 nonhematologic toxicity. RESULTS: Neutropenia was DLT, inasmuch as it occurred in three of five patients receiving gemcitabine 1,200 mg/m2. Nonhematologic toxicities were mild. Gemcitabine 1,100 mg/m2 plus carboplatin AUC 5 was recommended for phase II studies. An objective response was observed in 13 (50%) of 26 patients, including four complete responses (15%) and nine partial responses (35%). Median duration of response was 13 months (range, 3 to 23 months). Median overall survival was 16 months (range, 3 to 26 months). CONCLUSION: The combination of gemcitabine and carboplatin is well tolerated and active. Neutropenia was DLT. The observed activity matches that observable in cisplatin-gemcitabine studies, whereas duration of response and survival are even higher. A phase II trial is under way.
Osteoid osteoma. Direct visual identification and intralesional excision of the nidus with minimal removal of bone.
We describe 100 consecutive patients with osteoid osteoma. Of the 97 who had operations, 89 were treated by intralesional excision and eight by wide resection. The three remaining patients were not operated on because the osteoid osteoma was almost painless, or was found in the pedicle of the 12th thoracic vertebra at the site of entrance of the artery of Adamkjewicz. The diagnosis was confirmed histologically in all specimens. No local recurrences were observed at a minimum follow-up of one year. All except one patient were mobilised two to four days after surgery. A precise preoperative diagnosis of the lesion is mandatory, based on clinical findings, standard radiographs, thin-section CT and a bone scan. We compared our operative technique with 247 cases in which the percutaneous technique of removal or coagulation of the nidus had been performed. The latter procedure has a less constant rate of primary cure (83% v 100%). Its principal indication appears to be for osteoid osteomas in the proximal femur and the pelvis.
Secretory immunoglobulin A and cardiovascular activity during mental arithmetic and paced breathing.
The role of the autonomic nervous system in secretory immunoglobulin A (sIgA) responses to laboratory challenge was explored in a study in which sIgA and cardiovascular activity were recorded at rest and during mental arithmetic and paced breathing. These tasks were selected to preferentially engage the sympathetic and parasympathetic nervous systems, respectively. Mental arithmetic elicited a mixed pattern of increased alpha- and beta-adrenergic activity and a reduction in parasympathetic activity; diastolic blood pressure, total peripheral resistance, and systolic blood pressure increased, preejection period shortened, and heart rate variability decreased. In contrast, paced breathing primarily elicited an increase in parasympathetic activity; heart rate variability increased. Mental arithmetic also provoked an increase in sIgA concentration but no change in saliva volume, whereas paced breathing affected neither sIgA concentration nor saliva volume. These data suggest that sIgA responses to laboratory challenges are mediated by sympathetic rather than parasympathetic processes.
Differentiation-specific nuclear matrix proteins cross-linked to DNA by cis-diammine dichloroplatinum.
DNA-protein cross-linkages were performed in intact undifferentiated and differentiated-HL60 cells by the action of cis-diammine dichloroplatinum. Total nuclear matrix proteins and DNA cross-linked nuclear matrix proteins were resolved by two-dimensional gel electrophoresis. The comparison of the electrophoretic patterns allowed the identification of a set of differentiation-induced nuclear matrix proteins cross-linked to DNA. One of these proteins binds cloned histone SAR sequences. Our results outline an experimental strategy for isolating and characterizing nuclear matrix components that may play a fundamental role in the overall control and coordination of gene expression during differentiation.
Preoperative antimicrobial prophylaxis with a long-acting cephalosporin for thoracic surgery in 192 non small cell lung cancer patients.
The efficacy of preoperative antibiotic prophylaxis in thoracic surgery with a single dose of ceftriaxone was investigated. Here we report the results of a prospective study including 192 patients undergoing thoracic surgery for non small cell lung cancer. Overall, the postoperative infection rate, as measured by wound, respiratory tract, and urinary tract infections, was 8.3% (16/192). Ceftriaxone was well tolerated, and no allergic or other adverse reactions were reported. A single preoperative dose of ceftriaxone was cost-effective and allowed considerable saving of time, material, labor costs and money. This study, even though open and non-comparative, suggests that the routine use of a single preoperative dose of ceftriaxone provides a cost-effective prophylaxis for patients undergoing major thoracic operations.
[Epidemiologic study of 1768 burned patients].
A retrospective epidemiological study was made based on 1,768 burn patients admitted either to the Burns Unit or the general wards of the Plastic Surgery Department of Prelada Hospital in Oporto, from October 1988 until November 1997, corresponding to almost 8.5% of the overall patients admitted. The average age of the patients was 31.7 years and nearly 42% were children under 15 years old. The majority were male (60.8%), both in adults and children. The most frequent etiological agent was caused by fire (44.2%) and scalds (39%). About 74% of the patients required surgical treatment, with an average of nearly 2.3 operations per patient, of which 41.6% were surgical debridement or escarectomies and 40.8% skin grafting. The average hospital stay was 27.2 days and the overall mortality rate was nearly 6.8%, being much higher in adults (10.8%).
Glycosylation of RNA polymerase II from wheat germ.
RNA polymerase II from wheat germ was analyzed for the presence of sugars. The two largest subunits and the 27 and 25 kDa subunits were found to be glycosylated by a variety of sugars. However, no N-acetylglucosamine was detected, which was found by Kelly et al. (J. Biol. Chem. (1993) 268, 10416-10424) in the largest subunit of RNA polymerase II from calf thymus. Thus it appears that the regulatory function of this sugar, postulated by Kelly et al., is performed in the wheat germ enzyme by other monosaccharides. Carbohydrate analysis of the two largest subunits of the calf thymus enzyme also revealed the presence, beside N-acetylglucosamine, of other sugars. Some similarities in the features of glycosylation of the two polymerases, isolated from very different organisms, suggest that the sugar moieties have an important role in the structure and/or function of these enzymes.
Effects of scopolamine on delayed-matching-to-sample and paired associates tests of visual memory and learning in human subjects: comparison with diazepam and implications for dementia.
Two experiments examined dose-related effects of 200, 400 and 600 micrograms scopolamine (n = 24, s.c.) and 5 and 10 mg diazepam (n = 6, PO) on parallel tests of visual memory and learning taken from the CANTAB battery. Scopolamine significantly impaired accuracy of performance on a delayed matching to sample test of visual recognition memory in a dose- and delay-dependent manner, but had only marginal decremental effects on a test of visuospatial paired associates learning. Scopolamine significantly lengthened decision times in a visual search matching to sample task at the 400 and 600 micrograms doses, without significantly affecting accuracy. The drug also impaired performance on tests of spatial (on accuracy and response time measures) and pattern (on response time only) memory. Most of the deleterious effects on scopolamine were removed by covariance analyses with indices of subjective sedation, but the effects of delayed matching accuracy and latency remained. By contrast, diazepam significantly impaired paired associates learning but affected delayed matching to sample in a delay-independent manner. These results suggest that scopolamine can produce selective deficits in tests of short-term visual recognition memory which do not depend on overall impairments in arousal and which contrast with deficits in visual associative learning produced by diazepam. They have implications for the pharmacological modelling of dementia and memory disorders in man and for the neurochemical substrates of the short-term recognition memory and associative learning for visual stimuli.
Chemotherapy-induced tumor necrosis as a prognostic factor in localized Ewing's sarcoma of the extremities.
PURPOSE: This study was performed to assess the prognostic value of the proposed histopathologic method to evaluate the response of the primary tumor to preoperative chemotherapy in Ewing's sarcoma. PATIENTS AND METHODS: The response to chemotherapy was evaluated from the specimens of 118 Ewing's sarcoma patients, who were preoperatively treated by chemotherapy alone. Responses were graded I to III (macroscopic viable tumor, microscopic viable tumor, and no viable tumor cells, respectively). Follow-up data were available for all patients, with a mean follow-up duration of 86 months (range, 30 to 158). RESULTS: A statistically highly significant difference was observed in outcome among the three groups of patients. For patients with total necrosis (grade III response), the estimated 5-year disease-free survival rate was 95%, in contrast to 68% for grade II responders and 34% for grade III responders (P < .0001). This difference was also confirmed when any single group was compared with the other groups. Among the parameters tested, patient age and the size of tumor had some prognostic value. CONCLUSION: The proposed histopathologic grading, to evaluate the effect of chemotherapy on the primary tumor, had the strongest correlation to clinical outcome. This method could therefore be used to identify patients with a high risk of recurrent disease. These patients could be randomized to receive alternative postoperative treatments to investigate whether more aggressive therapies will improve outcome.
Comparison of DNA-protein interactions in intact nuclei from avian liver and erythrocytes: a cross-linking study.
DNA-protein cross-linkages were formed in intact nuclei of chicken erythrocytes and liver cells by the action of cis-diammine dichloroplatinum (II). Most cross-linked proteins were components of the nuclear matrix, and their heterogeneity reflected the different complexity of liver and erythrocytes matrices, respectively. Some basic proteins, including histones, were also cross-linked, particularly in erythrocyte nuclei. South-Western blotting revealed that a variety of proteins isolated from the cross-linked liver nuclei recognized DNA specifically. In this group of proteins two relatively abundant, acidic, species of 38 and 66 kDa, respectively, might represent novel DNA-binding proteins from the nuclear matrix. In the case of erythrocytes, only the basic proteins showed a DNA-recognition capacity, and among them there were some unidentified species, absent from liver. Lamin B2 was cross-linked but was unable to recognize DNA, and the same was true for other abundant, cross-linked proteins from both types of nuclei. This led to the hypothesis that for some DNA-nuclear matrix interactions the aggregation typical of matrix proteins is essential for the specificity of DNA recognition. Hybridization analysis of the DNA isolated from the cross-linked complexes showed that SARs (scaffold attachment regions) and telomeric sequences were well represented in the cross-linked fragments, that the cross-linked DNA of liver was partially different from that of erythrocytes and that two defined SAR sequences were found to be present only in the cross-linked DNA. These results are in agreement with the present views on DNA-nuclear matrix interactions, which are usually studied on isolated nuclear matrices or purified proteins. Instead, our results provide experimental evidence obtained directly from intact nuclei.
Purification of a 60-kDa protein from chicken liver associated with the internal nuclear matrix and closely related to carboxylesterases.
A 60-kDa protein was purified from chicken liver internal nuclear matrix and its nuclear localization was confirmed by immunofluorescence analysis. Structural information acquired from sequence analysis of the intact protein and of fragments obtained from enzymatic and chemical cleavages strongly suggests that it belongs to the carboxylesterases family, even if with some very peculiar features. The N-terminal sequence of the 60-kDa protein is completely different from the other carboxylesterases, but is similar to a region that is normally internal to all mammalian esterase sequences and localized after the serine residue at the active site. This suggests that the protein may be derived from a gene duplication and/or rearrangement. Since the 60-kDa protein shows a low esterase activity of about 0.2 micromol x min(-1) x mg(-1) using either p-nitrophenyl acetate or p-nitrophenyl butyrate as substrates, it is not possible to rule out that the protein shares only a sequence similarity with carboxylesterases and is not a true esterase. Otherwise it could be an esterase which has developed different properties, i.e. a special substrate specificity, the requirement of additional factors or a different stability in solution. In the latter case, this protein could be related to the physiological control of hydrolysis of exogenous and endogenous esters which can act on nuclear functions and/or metabolism.
Aneurysmal bone cyst and giant cell tumor of the foot.
From 1950 to 1994, 257 cases of benign bone tumors of the foot were treated at the Bone Tumor Center of the Rizzoli Institute. Aneurysmal bone cysts (ABC) and giant cell tumors (GCT) are rare and often they are misdiagnosed. To define the clinical and radiographic features useful for diagnosis, x-rays of 24 ABCs and 21 GCTs of the foot were reviewed. Adding our series to the cases reported in the literature, the only important clinical data that emerged was the average age of patients affected by ABC and GCT (15 and 27 years, respectively). ABCs localized in small tarsal bones were rare (6%), whereas 19% of GCTs were found in this site. The eccentric, round shape of a lytic lesion was more characteristic of GCT. An aggressive pattern of radiographic bone destruction was observed more frequently in GCT than in ABC (P = 0.01). Septation was seen in both tumors. Typical of ABC was a sharp and trabeculated margin, whereas GCT had an ill-defined edge with normal cancellous bone (P = 0.007). The growth of ABCs often expanded the cortex, while GCTs eroded, thinned, and broke the cortical bone (P = 0.001). A saucerized cortex was observed only in ABCs. A bony shelf was more characteristic of ABC than of GCT (P = 0.002). Pathologic fractures (67%) and joint involvement, evaluated by computed tomography and magnetic resonance imaging (83%), were more frequent in GCTs, whereas fluid levels were more frequently observed in ABCs (47%). The majority of the tumors were stage 2, but GCTs represented 70% of stage 3 aggressive lesions.
Intra-arterial versus intravenous cisplatinum (in addition to systemic Adriamycin and high dose methotrexate) in the neoadjuvant treatment of osteosarcoma of the extremities. results of a randomized study.
Intra-arterial (IA) and intravenous (IV) cisplatinum (CDP) were studied in a multiagent regimen of neoadjuvant chemotherapy for osteosarcoma of the extremities. Preoperatively two cycles of high-dose methotrexate (HDMTX) were administered, followed 5 days later by CDP and Adriamycin (ADM). MTX and ADM were administered IV, and CDP was delivered IA or IV. Postoperatively, good responders received 3 more cycles of the same drugs, while poor responders had a longer chemotherapy including ifosfamide. The rate of good histological response to chemotherapy was significantly higher in patients treated intraarterially (78% vs 46%: P < .004), while no significant differences in terms of disease-free survival were observed between patients who received CDP IA and patients who received CDP IV (55% vs 51%). In the IA group, however, there was only one local recurrence vs 5 in the IV group. The IA infusion of CDP is more active on the primary tumor than the IV infusion.