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C Barone

Publications and source records attributed to C Barone.

At least 37 records · Page 2Linked to original sources

Analysis of host range restriction determinants in the rabbit model: comparison of homologous and heterologous rotavirus infections.

The main limitation of both the rabbit and mouse models of rotavirus infection is that human rotavirus (HRV) strains do not replicate efficiently in either animal. The identification of individual genes necessary for conferring replication competence in a heterologous host is important to an understanding of the host range restriction of rotavirus infections. We recently reported the identification of the P type of the spike protein VP4 of four lapine rotavirus strains as being P[14]. To determine whether VP4 is involved in host range restriction in rabbits, we evaluated infection in rotavirus antibody-free rabbits inoculated orally with two P[14] HRVs, PA169 (G6) and HAL1166 (G8), and with several other HRV strains and animal rotavirus strains of different P and G types. We also evaluated whether the parental rhesus rotavirus (RRV) (P5B[3], G3) and the derived RRV-HRV reassortant candidate vaccine strains RRV x D (G1), RRV x DS-1 (G2), and RRV x ST3 (G4) would productively infect rabbits. Based on virus shedding, limited replication was observed with the P[14] HRV strains and with the SA11 Cl3 (P[2], G3) and SA11 4F (P6[1], G3) animal rotavirus strains, compared to the homologous ALA strain (P[14], G3). However, even limited infection provided complete protection from rotavirus infection when rabbits were challenged orally 28 days postinoculation (DPI) with 10(3) 50% infective doses of ALA rabbit rotavirus. Other HRVs did not productively infect rabbits and provided no significant protection from challenge, in spite of occasional seroconversion. Simian RRV replicated as efficiently as lapine ALA rotavirus in rabbits and provided complete protection from ALA challenge. Live attenuated RRV reassortant vaccine strains resulted in no, limited, or productive infection of rabbits, but all rabbits were completely protected from heterotypic ALA challenge. The altered replication efficiency of the reassortants in rabbits suggests a role for VP7 in host range restriction. Also, our results suggest that VP4 may be involved in, but is not exclusively responsible for, host range restriction in the rabbit model. The replication efficiency of rotavirus in rabbits also is not controlled by the product of gene 5 (NSP1) alone, since a reassortant rotavirus with ALA gene 5 and all other genes from SA11 was more severely replication restricted than either parental rotavirus strain.

Animals↗

Effect of acute and chronic administration of tamoxifen on GH response to GHRH and on IGF-I serum levels in women with breast cancer.

Tamoxifen, an estrogen antagonist, is usually employed in the treatment of breast cancer. Its mechanism of action is not well known because an antiproliferative effect of the drug has been shown also in estrogen receptor negative tumors, most likely mediated by the inhibition of local growth factors and particularly IGF-I. However, the action of tamoxifen on the GH-IGF-I axis is still open to investigation. We have investigated the influence of acute and chronic treatment with tamoxifen on GH response to GHRH and IGF-I serum levels in six postmenopausal women with metastatic breast cancer. A GHRH test (50 microg i.v. at time 0, GH determinations at 0, 15, 30, 60, 90 and 120 min) was performed (a) basally, (b) 3 h after 40 mg oral administration of tamoxifen and (c) after 8 weeks of 20 mg twice a day oral tamoxifen treatment. IGF-I was measured basally and after chronic tamoxifen therapy. No significant modifications in GH response to GHRH were observed after acute or chronic treatment with tamoxifen vs the basal test. On the contrary, chronic tamoxifen treatment induced a significant decrease in serum IGF-I levels. Basal pretreatment levels of 123+/-18 microg/l were suppressed to 65+/-11 microg/l (mean suppression 47%, P < 0.001). These preliminary data confirm the inhibitory effect of tamoxifen on IGF-I production but seem to exclude the possibility that this effect may be due to an inhibition of GH secretion.

Aged↗

[New developments in the treatment of medullary thyroid carcinoma].

Medullary thyroid carcinoma arises from the C cells, which produce a characteristic hormone, calcitonin. At present, surgery is the main treatment modality. Medullary thyroid carcinoma is usually treated with total thyroidectomy and with removal of nodes in the central portion of the neck and upper mediastinum. Cervical nodes dissection may be required for cancers affecting lateral neck nodes. Substitutive therapy with levo-thyroxine is indicated after surgery. External beam radiation therapy is not effective against advanced medullary thyroid carcinoma, while chemotherapy has a marginal activity. Biological therapy induces its anti-tumour activity through the inhibition of tumour cell growth without cytolysis and stimulating the antitumour immune response, in the absence of relevant side effects. On these bases, it can be suggested that chemo-refractory tumours could be still responsive to biological agents. In the last years somatostatin analogues and interferon have been used in the therapy of advanced and symptomatic medullary thyroid carcinoma, demonstrating an efficacious effect on neuroendocrine symptoms and on the production of calcitonin and an improving in quality of life. Even if there are no consistent data on the effects of biological agents on the reduction of tumour mass, the combined use of chemotherapy and biological therapy needs to be experimented in medullary thyroid carcinoma.

Carcinoma, Medullary↗

[Colovesical fistulae as a complication of diverticula: a report of 2 cases].

The authors report two cases of colovesical fistula as a complication of diverticular disease. They underline the increasing frequency of this complication, although the less frequent one. They also stress the importance of clinical and instrumental examinations that are several and among which TC scan can be crucial for surgical treatment. The therapy, exclusively surgical, can be made in one or two steps, according to patient status.

Aged↗

A 3-19-year follow-up study on diabetic retinopathy in patients diagnosed in childhood and treated with conventional therapy.

Few data are available from follow-up studies on diabetic retinopathy in patients diagnosed with insulin-dependent (Type 1) diabetes mellitus in childhood and treated with conventional therapy. We report the results of conventional insulin therapy on development of diabetic retinopathy in 100 children and adolescents (47 females and 53 males), aged 8.3 +/- 3.5 (1.2-16.4) years at diagnosis of disease. Oral or intravenous fluorescein angiography was performed during a 3-19 year follow-up in all patients. Retinopathy was staged according to the criteria of the Italian Society of Diabetology (SID). During follow-up, retinopathy was observed in 28 patients (28%). At the end of follow-up, retinopathy was present in 23 patients and had disappeared in 5. Life-table analysis showed a median disease-free interval of 10.8 years. At 10 years from diagnosis the percentage of patients free of retinopathy was 66%. Poor metabolic control, age, and degree of pubertal development at diagnosis were the most important risk factors.

Age Factors↗

Ambulatory blood pressure monitoring: how reproducible is it?

We tested the reproducibility of ambulatory blood pressure monitoring (ABPM) by the use of agreement plots. Thirty-two normotensive volunteers underwent ABPM on four separate days (interval 28 days), on the same typical weekday. Sleeping time was restricted to the ABPM nighttime subperiod from 11:00 PM to 7:00 AM. Twenty-four-hour average values-both systolic and diastolic-daytime average values, and nighttime average values, as well as standard deviation (SD) values, were analyzed for differences (analysis of variance). Adaptation occurred from the first to the fourth ABPM, ie, average 24 h, daytime, and nighttime values were lower (-1 to -3 mm Hg) during the fourth recording than the first (P < .05 to P < .01). The agreement analysis showed a surprisingly high agreement among the four data sets (ie, differences from +/-2.54 to +/-5.92 mm Hg; +/-2 SD of the distribution). We concluded that reproducibility of ABPM seems excellent, but adaptation may occur, even in normotensive volunteers under research conditions. Caution must be paid before labeling a patient as hypertensive, because initial ABPM may yield higher values than later monitorings.

Adult↗

Peritoneal mesothelioma in recurrent familial peritonitis.

A 39-year-old man had a 2-year history of fatigue, weight loss, drug-resistant ascites, and decreased intestinal motility. During adolescence he began to suffer frequent episodes of acute benign peritonitis that spontaneously subsided at age 35. The fact that his younger brother was taking colchicine for the same symptoms led us to diagnose familial Mediterranean fever (FMF). The medical workup revealed uniform thickening of the intestinal wall with no signs of amyloidosis. Exploratory laparotomy revealed diffuse peritoneal mesothelioma that proved to be unresponsive to chemotherapy. There was no history of asbestos exposure. It is probable that the chronic peritoneal inflammation was responsible for the development of this tumor, although in almost all cases of FMF this phenomenon causes only limited peritoneal fibrosis or, less commonly, encapsulating peritonitis. A computerized search of the literature indicates that this is the second report of peritoneal mesothelioma associated with FMF.

Adult↗

[Retroperitoneal tumors: personal experience].

The Authors experience in five retroperitoneal tumors with symptoms and histopathological characteristics not different from those described in the Literature, is here reported. Topographic findings, classification, and incidence of retroperitoneal tumors as referred by various Authors are discussed. Two aspects are particularly pointed out: the histological type and the surgical strategy for their removal. Concerning the first aspect, the Authors underline that benign lesion may have an optimal outcome and a long survival, unlike the malignant ones, which have always unfavourable prognosis, despite adjuvant and complementary therapy (radiotherapy, chemotherapy). As for the second aspect, surgery is the treatment of choice even when other organs different from those exclusively retroperitoneal, may be involved in the demolition.

Adult↗

Rotavirus subunit vaccines.

We evaluated rotavirus subunit vaccines for use in humans and animals. Insect cells were co-infected with combinations of individual baculovirus recombinants expressing human, bovine or simian rotavirus VP2, VP4, VP6 or VP7 to produce virus-like particles (VLPs). To determine whether immunization with VLPs could induce active protective immunity, VLPs were administered parenterally to rabbits, and the immune response and protection from rabbit ALA rotavirus challenge were evaluated. Complete or partial protection was attained, showing that parenteral immunization with VLPs induces active protective immunity. We also examined whether heterotypic immune responses could be induced with a limited number of broadly reactive VP7 proteins or with chimeric particles (multiple VP7 types on individual particles). The feasibility of this approach was determined by immunizing mice with VLPs containing a G3 VP7 or G1 VP7 and chimeric G1/G3 VLPs. Broadly reactive neutralizing antibody was induced by the G1 VLPs. VLPs also have been successfully used to boost lactogenic (colostral and milk) immunity in dairy cows. Taken together, these results show that VLPs can be effective immunogens in rabbits, mice and dairy cattle when administered parenterally, a limited number of VLPs may be sufficient to produce a broadly protective vaccine, and G3 VLPs may serve as an effective subunit vaccine for use in bovines.

Animals↗

Effect of cisplatin in advanced colorectal cancer resistant to 5-fluorouracil plus (S)-leucovorin.

Modulation of 5-fluorouracil (5-FU) is currently being investigated in advanced colorectal cancer. In an attempt to improve the results obtainable for the association of 5-FU and leucovorin, we decided to add cisplatin to 5-FU and (6S)-leucovorin (S-LV) after disease progression. The hypothesis was that a pharmacological enhancement of the efficacy of 5-FU would result in responses in 5-FU-unresponsive patients or in a second response in previously responding patients. A group of 28 5-FU+S-LV-pretreated patients, with advanced measurable colorectal cancer, were treated with 80 mg/m2 cisplatin on day 1, 80 mg/m2 S-LV and 370 mg/m2 5-FU as an i. v. bolus for 5 consecutive days every 4 weeks. We obtained 3 partial responses (response rate: 11 +/- 11%), while 11 patients had stable disease (39 +/- 18%). Among the 3 responders, 1 patient had earlier achieved a partial response, a second stable disease and 1 had disease progression after the previous 5-FU+S-LV treatment. The median survival time for all 28 patients was 11 months. Toxicity was minimal and consisted of mild and reversible gastrointestinal symptoms and myelosuppression. We believe that further studies must be carried out to establish the real impact of the synergism between cisplatin, 5-FU and S-LV in untreated patients.

Adenocarcinoma↗

No safe haven: a study of violence exposure in an urban community.

OBJECTIVE: To examine levels of violence exposure and reports of feeling unsafe in relation to psychological and behavioral characteristics for a general population sample of youths from an urban setting. METHOD: A comprehensive survey of high-risk behaviors, attitudes, indicators of adaptive behavior, and daily involvements was administered to a sample of 2,248 students in the 6th, 8th, and 10th grades in an urban public school system. RESULTS: More than 40% of the youths surveyed reported exposure to a shooting or stabbing in the past year, and 74% reported feeling unsafe in one or more common environmental contexts. Multiple regression analyses indicated significant relationships between violence exposure/feeling unsafe and a set of indicators of psychological and behavioral adaptation and expressed attitudes. CONCLUSIONS: These results attest to the picture of violence as a common fact of inner-city life and to the demand that is placed on urban youths to accommodate in their psychological development to chronic threat and lack of safety.

Anxiety Disorders↗

Positivity of patch tests in cutaneous reaction to diclofenac. Two case reports.

Immune-mediated reactions to NSAIDs are unusual. We have observed two cases of maculopapular eruptions occurring 48-72 h after administration of diclofenac sodium. Patch tests performed with diclofenac were positive. The histopathologic findings resembled those of contact dermatitis with different degrees of dermal involvement. Clinical, allergologic, and histopathologic patterns strongly suggest a type IV mechanism of hypersensitivity. Patch tests play an important role in the assessment of possible immunologic mechanisms underlying cutaneous reactions to drugs.

Adult↗

Rotavirus vaccine administered parenterally induces protective immunity.

We performed experiments to determine whether parenteral immunization with SA11 rotavirus can induce active protective immunity in a rabbit model of rotavirus infection. After one or two intramuscular injections of 1 ml of live or formalin-inactivated SA11 virus, we evaluated the mucosal and serologic immune response and protection from challenge with a high dose of live, virulent rabbit (Ala) rotavirus. Inactivated SA11 virus preparations, evaluated by enzyme-linked immunosorbent assay (ELISA) with a panel of VP4- and VP7-specific neutralizing and nonneutralizing monoclonal antibodies, did not show a loss of epitopes from the inactivation procedure compared with live virus. Administration of two doses of vaccine, one at zero days postvaccination (DPV) and a booster shot at 49 DPV, followed by challenge at 71 DPV with 3.5 x 10(5) PFU of Ala virus resulted in protection from challenge. None of the two-dose virus-vaccinated rabbits shed virus after challenge, while virus shedding was detected in all control rabbits (P = 0.001, Fisher's exact two-tailed test). Differences in total serum immunoglobulin (Ig) antirotavirus ELISA titers (P < 0.05, Wilcoxon's rank sum test) were observed between groups vaccinated with virus in aluminum phosphate or Freund's adjuvant but not between groups vaccinated with live or inactivated virus in either adjuvant. All rabbits given two doses of vaccine had detectable antirotavirus intestinal antibody of the IgG, but not IgA, isotype. After challenge, fourfold or greater increases in intestinal IgG antibody responses were observed in three rabbits, whereas all controls and all but one virus-vaccinated rabbit had an intestinal IgA antibody response. In contrast, vaccination of rabbits with one dose of SA11 followed by challenge at 21 DPV did not protect from challenge; no difference in the mean number of days of virus shedding between any of the vaccinated groups and controls was observed. A serologic, but not a mucosal, antibody response was observed after the one-dose vaccination regimen. Differences in serologic antibody titers were not observed between any of the one-dose virus-vaccinated groups. These data indicate that parenteral vaccination with two, but not one, doses of rotavirus in either Freund's adjuvant or aluminum phosphate can induce active protection from challenge.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Social improvement after the Wilke procedure for excessive drooling.

The child with an excessive drooling problem often faces similar social deprivation to those with severe craniofacial malformations. Many of these children have other "strikes against them" (such as cerebral palsy) that, when coupled with drooling, isolate them from social interaction. Many methods have been employed to control drooling but surgery has been most consistently successful. The most popular of these has been the Wilke procedure or a modification of it. Several series have been reported, but a detailed correlation of mechanical success with the effects on social activity has not been reported. We reviewed a series of 23 cases of Wilke-type surgery. Analysis of the results showed a convincing improvement in social activity after successful surgery. The Wilke procedure enjoys a relatively high rate of success in preventing excessive drooling, which seems to offer a dramatic improvement in social contact enjoyment.

Adolescent↗