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Biomedical subjects

A Crescenzi

Publications and source records attributed to A Crescenzi.

At least 19 recordsLinked to original sources
PubMed2004

Characterisation of Potato virus Y nnp strain inducing veinal necrosis in pepper: a naturally occurring recombinant strain of PVY.

The full-length genome of Potato virus Y (PVY) nnp strain, recovered from pepper showing veinal necrosis of leaves, was cloned and sequenced, finding an organisation typical for PVY species. It consists of 9699 nucleotides (nt) excluding the 3' terminal poly(A) tail and contains an open reading frame of 9186 nt, encoding the putative polyprotein of 3061 amino acids. In ELISA, the isolate reacted with a monoclonal antibody specific for PVY(C) but not with antibodies against PVY(N) or PVY(O). Sequence analysis strongly suggests that PVY-nnp originated from a recombination event involving a virus of the PVY(O) type and another parental virus, maybe resembling the PVY(NP) isolates, given the reasonably high similarity shared by PVY-nnp and Lye84.2 and Son41 isolates. The recombination event involved a breakpoint near the middle of the P1 gene, around position 603 of the viral genome. Proof for the existence of such a recombination comes from several lines of evidence, including similarity analysis, recombination analysis using six different methods and the different locations of nnp within phylogenetic trees constructed from genomic regions on either side of the identified recombination breakpoint.

Base Sequence↗
PubMed2004

Severe outbreaks of tomato yellow leaf curl Sardinia virus in Calabria, Southern Italy.

During the winter 2003--2004 a serious disease was observed in protected tomato crops in Castrovillari, Reggio Calabria province, Southern Italy. Symptoms consisted in marginal leaf yellowing, leaf curling, plant stunting, flower abortion. The disease was detected in a group of greenhouses (about 10ha) where several tomato cultivars were grown hydroponically. The highest incidence of infection (60-100%) was observed in tomatoes grafted on Beaufort DRS tomato rootstock. Since the symptoms were similar to those described for Tomato yellow leaf curl Sardinia virus (TYLCSV) and Tomato yellow leaf curl virus (TYLCV), detection assays for these viruses were used. In DAS-ELISA positive results were obtained with a abroad-spectrums reagent combination (distributed by Bioreba AG) detecting TYLCV, TYLCSV, and other begomoviruses. When DNA probes were used in tissue print assays, positive reactions were obtained for TYLCSV, but not for TYLCV. The two probes consisted of digoxigenin-labelled DNAs representing the coat protein gene of either TYLCSV or TYLCV. Attempts to isolate the viral agent by mechanical inoculation failed, except in few cases where Potato virus Y and Tobacco mosaic virus were identified following transmission from symptomatic plants to herbaceous indicatorpplants. By contrast, grafting onto tomato seedlings always successfully transmitted the disease. In the Castrovillari area TYLCSV was not reported before. The rootstocks that nurseries used for grafting were obtained from Sicily, where the disease is endemic and both TYLCSV and TYLCV are widespread. Probably the grafted plantlets represented the primary source of infection from which subsequent diffusion by way of the vector Bemisia tabaci followed. In fact the vector had previously been detected in both the glasshouse-grown and open field tomato crops in Calabria region. TYLCV was previously reported in a different area of Calabria in 1991, but apparently it was an occasional outbreak, and B. tabaci was not detected. Since in the Castrovillari area surveyed in the present study tomato is grown throughtout the year in protected crops, the whitefly vector of the virus is present, and some natural hosts of the virus are found, it is feared that TYLCSV may become endemic, as already happened in Sicily, Sardinia, and Spain several years ago. In Spain and Sicily TYLCV, together with TYLCSV, was reported as the causal agent of very severe tomato crop losses. Therefore the danger exists that also TYLCV will reach this area, furthermore complicating the management of tomato crops.

Agriculture↗
PubMed2003

Localization and expression of thyroid hormone receptors normal and neoplastic human thyroid.

The aim of this study was to investigate the regional expression of thyroid hormone nuclear receptor forms (TR(alpha) and TR(beta)) and isoform (TR(alpha1) and TR(beta2)) mRNAs in normal and neoplastic (benignant and malignant) human thyroid tissue. Tumor specimens from patients with thyroid carcinomas (papillary: 5 cases; follicular: 5 cases; anaplastic: 2 cases), thyroid follicular adenomas (7 cases) and tissue from normal thyroid glands (12 cases) were analyzed by in situ hybridization and semiquantitative RT-PCR for the expression of TR(alpha1) and beta, as well as for the isoform alpha2 that does not bind the hormone. In normal tissues, TR(alpha2) was expressed at lower levels compared to TR(alpha1) (alpha1/alpha2 = 4.3). In papillary and follicular carcinomas, the expression of TR(alpha1) and TR(beta) did not change as compared with normal thyroid tissue and adenomas (0.87 +/- 0.15 SD vs 0.89 +/- 0.17 densitometric units, DU, and 0.15 +/- 0.02 vs 0.14 +/- 0.03 DU, respectively). However, the expression of TR(alpha2) was significantly higher in differentiated carcinomas compared to normal thyroid tissue and adenomas (0.47 +/- 0.05 vs 0.20 +/- 0.05 DU, p < 0.05) with alpha1/alpha2 = 1.4. In anaplastic carcinoma all TRs were absent. We concluded that both normal and pathological thyroid tissues, with the exception of anaplastic carcinoma, express all TRs in thyreocites and that differentiated thyroid carcinomas are associated in enhancing the expression of TR(alpha2) mRNA.

Adenocarcinoma, Follicular↗
PubMed2003

The complete nucleotide sequence of Plum pox virus isolates from sweet (PPV-SwC) and sour (PPV-SoC) cherry and their taxonomic relationships within the species.

Plum pox virus (PPV) sweet (SwC) and sour (SoC) cherry isolates were the first PPV isolates to be recovered from natural infection in sweet and sour cherry plants, respectively. Their complete nucleotide sequences have been determined finding a deduced genome organisation typical for PPV species. Both genomes are 9795 nucleotides long, excluding the 3' terminal poly(A) tail, and contain an open reading frame of 9432 nt, encoding a polyprotein of 3143 amino acids. The nucleotide and predicted amino acid sequences of PPV-SwC and SoC have been pairwise compared with available sequences of different PPV strains. Although a very high similarity exists between the whole genomes and polyproteins of the two cherry isolates, high levels of divergence have been calculated with sequences of PPV-M, D and EA isolates. In particular, the most considerable divergence has been found in part of 5' non coding region, in regions encoding P1, P3 + 6K1, 6K2 and NIa-VPg proteins as well as in the N-terminal domain of the coat protein. Phylogenetic analysis have been undertaken in order to establish the taxonomic localisation of SwC and SoC isolates within PPV species, showing that they are always clustered together and separated from the rest of PPV strains, being clearly the most distant.

5' Untranslated Regions↗
PubMed2003

A new mathematical model based on clinical and laboratory variables for the diagnosis of Sjögren's syndrome.

Sjögren's syndrome (SS) is a systemic autoimmune disease that mainly affects exocrine glands. A diagnosis of SS in its early stages has a potential clinical relevance, but it is difficult and cannot be made solely on clinical grounds. Several sets of diagnostic criteria have been proposed, but none has met with a general consensus. Minor salivary gland has been judged to be the "gold standard" for the diagnosis of SS. However, it is a painful procedure and has a small but significant proportion of both false positive and false negative results. The aim of our study was to develop a simple mathematical score that uses clinical and laboratory variables for diagnosing SS, thereby reducing the need of minor salivary gland. The following variables were included in the model: ANA, SS-A/SS-B, Schirmer's Test/BUT, C3/C4, serum gammaglobulin levels. One hundred consecutive individuals reporting clinical syndromes consistent with a sicca syndrome were included in the study. The application of our multifactorial mathematical model has shown a high predictive value for SS vs controls or vs patients with other autoimmune disorders (Sensitivity 93%, Specificity 100%), with an estimated minor salivary gland reduction of 77%. We conclude that our mathematical model can be considered a useful non-invasive approach for diagnosing Sjogren's Syndrome and recommend its validation on a larger scale.

Adult↗
PubMed2000

Mucosal changes in ileal pouches after restorative proctocolectomy for ulcerative and Crohn's colitis.

PURPOSE: Inflammation and dysplasia may affect the ileal pouch after restorative proctocolectomy and ileal pouch-anal anastomosis. The aim of this prospective study was to evaluate the morphologic changes and the risk of dysplasia within the pouch after ileal pouch-anal anastomosis. METHODS: Thirty-seven patients with ileal pouch-anal anastomosis underwent endoscopies and biopsies of the pouch: 21 patients were affected by ulcerative colitis and 16 by Crohn's colitis. The mucosal biopsy specimens were studied to investigate the degree of acute and chronic inflammation and the occurrence of dysplasia. A score system was calculated for each patient and correlated with the histologic diagnosis of ulcerative colitis or Crohn's colitis. RESULTS: After a median follow-up of 85 (range, 7-198) months, the inflammation histologic score evaluated was 3.8 (95 percent confidence interval, 2.4-5.1) and 3.5 (95 percent confidence interval, 2.6-4.3), respectively, in patients with Crohn's colitis and ulcerative colitis (mean and 95 percent confidence interval; P = 0.74, not significant), and no patient developed mucosal dysplasia. Fifteen patients (40.5 percent) developed clinical pouchitis that occurred in Crohn's colitis (9/16 patients or 56 percent) and in ulcerative colitis (6/21 patients or 28 percent; P not significant). The score was 4.1 (95 percent confidence interval, 3.2-5) in patients with pouchitis and 3.2 (95 percent confidence interval, 2.1-4.3) in patients without clinical pouchitis (P = 0.012) and was 4.1 (95 percent confidence interval, 2.6-5.5) and 4 (95 percent confidence interval, 2.9-5.3), respectively, in pouchitis patients with Crohn's colitis and ulcerative colitis. CONCLUSION: No difference in the inflammation histologic score was observed in ileal pouches after restorative proctocolectomy for ulcerative and Crohn's colitis. In our series, which includes those patients with longer follow-up (>5 years) or with chronic unremitting pouchitis, no case of dysplasia was found. The occurrence of pouchitis was higher in the case of ileal pouch-anal anastomosis for Crohn's disease than for ulcerative colitis, but no difference in the severity of the histologic score was noted.

Adult↗
PubMed2000

Thyroid tissue: US-guided percutaneous interstitial laser ablation-a feasibility study.

PURPOSE: To evaluate percutaneous interstitial laser photocoagulation (ILP) as a palliative treatment of recurrent thyroid carcinoma untreatable with surgery or radioiodine administration. MATERIALS AND METHODS: By using 18 resected thyroid glands, the volume and histologic pattern of ILP-induced thyroid damage were assessed. In vivo treatment feasibility was evaluated by using a low-energy laser in two volunteers before thyroidectomy for huge autonomously functioning nodules. With ultrasonographic (US) monitoring, a 21-gauge spinal needle was inserted into the thyroid nodules. A 300-microm quartz fiberoptic guide was inserted through the needle lumen, and the fiber tip was placed in direct contact with the tissue. Laser irradiation was performed with a 1.064-nm Nd:YAG laser in surgically resected glands, which were treated with 2, 3, 5, or 7 W. RESULTS: Tissue ablation was well-defined histologically, and its area was related to laser irradiation parameters (range, 0-26 mm). No correlation was found between US images and the actual extent of laser-induced lesions. Large colloid or fluid collections did not permit regular heat diffusion within the tissue. In vivo low-energy ILP was performed without technical difficulties or complications. CONCLUSION: ILP induces well-defined tissue ablation correlated with energy parameters in thyroid glands devoid of cystic areas. ILP could be a therapeutic tool for highly selected problems in thyroid tumor treatment.

Analysis of Variance↗
PubMed2000

Evidence of UCP1-independent regulation of norepinephrine-induced thermogenesis in brown fat.

UNLABELLED: To study the thermal response of interscapular brown fat (IBF) to norepinephrine (NE), urethan-anesthetized rats (1.2 g/kg ip) maintained at 28-30 degrees C received a constant venous infusion of NE (0-2 x 10(4) pmol/min) over a period of 60 min. IBF temperatures (T(IBF)) were recorded with a small thermistor fixed under the IBF pad. Data were plotted against time and expressed as maximal variation (Deltat degrees C). Saline-injected rats showed a decrease in T(IBF) of approximately 0.6 degrees C. NE infusion increased T(IBF) by a maximum of approximately 3.0 degrees C at a dose of 10(4) pmol x min(-1) x 100 g body wt(-1). Surgically thyroidectomized (Tx) rats kept on 0.05% methimazole showed a flat response to NE. Treatment with thyroxine (T(4), 0.8 microg x 100 g(-1) x day(-1)) for 2-15 days normalized mitochondrial UCP1 (Western blotting) and IBF thermal response to NE, whereas iopanoic acid (5 mg x 100 g body wt(-1) x day(-1)) blocked the effects of T(4). Treatment with 3,5, 3'-triiodothyronine (T(3), 0.6 microg x 100 g body wt(-1) x day(-1)) for up to 15 days did not normalize UCP1 levels. However, these animals showed a normal IBF thermal response to NE. Cold exposure for 5 days or feeding a cafeteria diet for 20 days increased UCP1 levels by approximately 3.5-fold. Nevertheless, the IBF thermal response was only greater than that of controls when maximal doses of NE (2 x 10(4) pmol/min and higher) were used. CONCLUSIONS: 1) hypothyroidism is associated with a blunted IBF thermal response to NE; 2) two- to fourfold changes in mitochondrial UCP1 concentration are not necessarily translated into heat production during NE infusion.

Adipose Tissue, Brown↗
PubMed2000

Ontogenetic pattern of thyroid hormone receptor expression in the human testis.

We studied the spatiotemporal distribution of thyroid hormone nuclear receptors (TRs) alpha1 and alpha2 and beta messenger RNA (mRNA) levels in normal human testicular tissue during development and in adulthood. Nonpathological specimens from five aborted fetuses (17 and 23 weeks of gestation, three and two cases, respectively) and from four patients undergoing orchiectomy (18 months old and 38-, 42-, and 52-yr-old, respectively) were analyzed by Northern blot, semiquantitative RT-PCR amplification using DNA sequences or specifically designed primers for the TR isoforms, and in situ hybridization. By using PCR amplification, we found that TRalpha1 and TRalpha2 are both expressed at different levels in fetal and adult testis. At all ages TRalpha2 is found at higher levels. Northern analysis showed hybridization signals corresponding to the expression of TRalpha2 and TRalpha in a ratio that increased from 2.6 at 17 weeks of gestation to 12.0 in adulthood. In fact, the expression of TRalpha1 dramatically decreased throughout development, being faintly detectable in the adult testis. Expression of TRbeta was not detected at any age studied. This finding was further confirmed by PCR, which did not amplify TRbeta either in fetal or in adult testis mRNAs. In situ hybridization studies showed the absence of TRbeta and that TRalpha1 and TRalpha2 colocalized in Sertoli cells of prepubertal testis, whereas germ and interstitial cells appeared devoid of TR mRNA signals. From these results it can be concluded that the human testis exclusively expresses TRalpha, which is localized in Sertoli cells, TRbeta being always undetectable. Fetal and prepubertal ages represent the period of maximal expression of TRalpha1 and TRalpha2. The alpha2/alpha1 ratio rises dramatically after development. These results confirm a critical window for the action of thyroid hormone in human testis, in the period of maximal expression of T3 binding isoform TRalpha1, and may account for the macroorchidism without virilization occurring when hyposecretion of thyroid hormones occurs before puberty.

Adult↗
PubMed1999

Severe thyrotoxicosis due to hyperfunctioning liver metastasis from follicular carcinoma: treatment with (131)I and interstitial laser ablation.

Liver metastases from differentiated thyroid tumors are unusual clinical findings, and are only rarely hyperfunctioning. We report a case of thyrotoxicosis caused by a huge and surgically unresectable liver metastasis from follicular thyroid cancer, unresponsive to treatment with large doses of thionamides. To avoid the hazardous side effects of (131)I treatment in a severely thyrotoxic patient, a preliminary debulking of the liver mass was performed by means of percutaneous interstitial laser photocoagulation. Three treatments (total energy delivery: 7200 J) were performed under ultrasound guidance, with no serious complications, during a 2-week period. One month later, serum thyroid hormones had decreased, general condition was improved, and magnetic resonance evaluation revealed large and well-defined areas of necrosis of metastatic tissue. During the following 10 months, the patient underwent 3 radioiodine treatments. Eighteen months after diagnosis, thyroid hormones were within normal levels, liver mass decreased, and the clinical condition markedly improved. The combination of percutaneous interstitial laser photocoagulation treatment and radioiodine therapy made possible the effective management of a hyperfunctioning and surgically untreatable liver metastasis from thyroid follicular carcinoma, avoiding the side effects of (131)I therapy in a thyrotoxic patient and increasing the effectiveness of radioiodine-induced neoplastic tissue ablation.

Adenoma↗
PubMed1999

Screening of thyrotropin receptor mutations by fine-needle aspiration biopsy in autonomous functioning thyroid nodules in multinodular goiters.

Multinodular goiter (MNG) is characterized by nodules of different size and function. Areas of increased function may emerge, appearing as single, or more frequently, multiple autonomously functioning thyroid nodules (AFTN). The molecular mechanism for the autonomous growth and function of these nodules has been related to mutations in the thyrotropin receptor (TSHR) that constitutively activate the adenylyl cyclase. We searched for mutations in a limited area of the TSHR gene, covering the major mutational hotspot, in 38 AFTNs found in 37 patients with MNGs. We used reverse transcriptase-polymerase chain reaction (RT-PCR) and restriction enzyme analysis of fine-needle aspiration biopsy (FNAB) samples to rapidly identify 4 of the more frequently occurring TSHR mutations: D619G, F631C, T632I and D633E. Mutations were identified in 5 nodules (1 D619G mutation and 4 T632I mutations). Subsequently, the entire transmembrane portion of the TSHR gene was sequenced in a random sample of 12 AFTN samples that were free of mutations by RT-PCR and restriction enzyme analysis. By direct sequencing we identified a new mutation, F666L, in the seventh transmembrane domain in a sample from 1 nodule. Analysis of FMA samples of AFTN is an effective approach to identify TSHR gene mutations because individual mutations may be associated with different growth and function in vitro, our approach might, allow correlation of a given mutation with the clinical behavior in vivo.

Adult↗
PubMed1999

Cytospray fixation of frozen intraoperative sections.

Preservation of cellular morphologic features is well known to be a limit of intraoperative frozen sections. Various techniques have been proposed to improve tissue details, the most common being ethanol immersion of cryostatic slide. We tested fixation with spray formulation for cytology smears on intraoperative frozen section from different organs to obtain a quick alcoholic fixation and a ready-to-use method. Our results of comparative study showed that cytospray fixation of frozen sections provide a significant improvement of cellular details, that it is quick, simple, economic, and that it does not require preorganization.

Aerosols↗
PubMed1998

Circular dichroism studies of CMV-D and CMV-S: two strains of cucumber mosaic cucumovirus with a different biological behaviour.

Cucumber mosaic cucumovirus is a plant virus in which a typical satellite RNA system is present, displaying a dualistic biological behaviour. In fact, it has been shown that satRNA is able either to aggravate or attenuate the viral disease symptomatology with a modulating capability going from death of the host plant to a surprising absence of symptoms. D-satRNA and S-satRNA have been considered the prototype necrogenic and non necrogenic satRNAs respectively. On the basis of circular dichroism spectroscopy, it is suggested that the different biological behaviours can be explained by taking into account the different capabilities exerted by S- and D-satRNAs in inducing structuring effects onto CMV-S and CMV-D genomic RNAs.

Circular Dichroism↗
PubMed1998

Long-term changes in nodular goiter: a 5-year prospective randomized trial of levothyroxine suppressive therapy for benign cold thyroid nodules.

We studied for 5 yr a homogeneous group of 83 patients randomly assigned to a levothyroxine (L-T4) suppressive therapy or to a control group to evaluate changes in nodule or thyroid size, appearance of new nodules, and correlations with clinical parameters. In the control group, mean nodule volume increased significantly after 5 yr (2.12 +/- 1.46 vs. 1.46 +/- 0.77 mL), whereas in the treatment group it decreased, although not significantly (1.45 +/- 1.17 mL vs. 1.53 +/- 0.61 mL). Baseline nodule volume was not different in the two groups, but a significant difference was observed at 5 yr. After 5 yr, sonograms detected 12 new nodules in the control group (28.5%) and 3 (7.5%) in the treatment group. Nodule shrinkage was more frequent in patients with complete TSH suppression, but no correlation was found with other parameters. A significant increase in thyroid size was observed in the control group. In conclusion, long term TSH suppression induced volume reduction in only a subgroup of thyroid nodules, but effectively prevented the appearance of new lesions and increases in nodule and thyroid volume. As the changes in the natural history of nodular goiter are related to prolonged TSH suppression, which can induce unfavorable side-effects, L-T4 suppressive therapy should be reserved for small nodules in younger patients.

Adult↗
PubMed1997

Production of strain specific antibodies against a synthetic polypeptide corresponding to the N-terminal region of the plum pox potyvirus coat protein.

Comparison of the predicted coat protein amino acid sequence of the 'sweet cherry' strain of plum pox potyvirus (PPV-SwC) with the corresponding regions of several other PPV strains indicated that the main differences are in the N-terminal region. Polyclonal antibodies were produced against a synthetic peptide corresponding to the 1-14 sequence of the N-terminal region of PPV-SwC coat protein. They specifically detected PPV-SwC in different immunochemical tests.

Amino Acid Sequence↗
PubMed1997

Response to recombinant human erythropoietin in patients with myelodysplastic syndromes.

Recombinant human erythropoietin (rhEPO) at pharmacological doses was used to improve anemia and reduce the transfusional requirements of 43 patients with myelodysplastic syndrome (MDS). rhEPO was given by s.c. injection three times per week for 12 weeks. The EPO dose was started at 150 IU/kg and was increased to 300 IU/kg if after 6 weeks there was no or suboptimal erythroid response. Responses were defined as being a complete response (CR), partial response (PR), or no response (NR). A CR was considered a rise in untransfused hemoglobin concentrations of at least 2 g/dl or a 100% decrease in RBC transfusion requirements over the treatment period. A PR was defined as an increase in untransfused hemoglobin values of 1-2 g/dl or a decrease in RBC transfusion requirements equal to or greater than 50%. NR was defined as responses less than a PR. Patients who responded to therapy were continued on rhEPO at the same dose for 6 additional months. An objective response (CR and PR) was observed in 7 of 42 (16.7%) assessable cases after 6 weeks of treatment at the dose of 150 IU/kg. Dose escalation (300 IU/kg) in nonresponders resulted in another six patients attaining a rise in hemoglobin concentrations. The final response rate was 13 of 41 (31.7%); 4 patients became transfusion independent. Therapy was tolerated well, with no relevant side effects. MDS progression was seen in one case. An elevated bone marrow erythroid infiltration (erythroid index) and detectable pretreatment circulating erythroid progenitors (burst-forming units-erythroid) were the best predictors of hemoglobin response when we controlled for other variables. These data suggest that rhEPO has a role in the treatment of certain patients with MDS, particularly in those with a high erythroid index and detectable circulating erythroid burst-forming units.

Adult↗
PubMed1996

Morphological changes in a hyperfunctioning thyroid adenoma after percutaneous ethanol injection: histological, enzymatic and sub-microscopical alterations.

Ultrasound-guided ethanol injection (PEI) is an effective treatment of autonomously functioning thyroid nodules (AFTN) but little is known about the tissue lesions induced by alcohol. We report morphological changes of an AFTN which was removed after successful PEI treatment. At histological evaluation, the adenoma showed multiple areas of coagulative necrosis with eosinophilic ghost follicles, hemorrhages, small vessel thrombosis and a wedge-shaped hemorrhagic infarction. The peripheral adenomatous tissue and the surrounding thyroid parenchyma were free of regressive changes and/or lympho-monocytic inflammatory reactions. Enzyme histochemistry confirmed the hyperfunctioning character of the lesion and showed reduction of succinic dehydrogenase and cytochrome-c-oxydase activity in the viable tissue surrounding the central necrotic areas. By electron microscopy, the hyperfunctioning follicular epithelium showed submicroscopical alterations of the adenomatous cells surrounding the areas of coagulative necrosis. These results suggest that control of hyperthyroidism, after PEI, is due to: a) directly induced, irreversible damage (coagulative necrosis and vascular thrombosis with hemorrhagic infarction) in the central areas of the lesion; b) potentially reversible damage (reduction of intracellular enzyme activity and ultrastructural changes) in the peripheral areas.

Acid Phosphatase↗