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Biomedical subjects

A Russo

Publications and source records attributed to A Russo.

At least 397 records · Page 22Linked to original sources
PubMed1993

Persistence of chromosomal lesions induced in mouse bone marrow cells by mitomycin C, as evaluated by SCE analysis.

The frequency of sister-chromatid exchanges (SCE) was evaluated in mouse bone marrow cells at different time intervals (from 19 h to 10 days) after treatment i.p. with mitomycin C (MMC; 1 and 2 mg/kg body weight). Significantly higher frequencies of SCE were found during the first week after treatment, at both doses tested. This result confirms that chromosomal lesions induced by MMC in the mouse may persist in bone marrow cells, in agreement with previous evidence based on chromosomal aberration analysis in the same cell population. In addition, the observation of a unimodal distribution of SCE/cell frequencies at each time tested indicates that the bone marrow cell population on the whole is affected by increased SCE frequency, i.e., that persistent chromosomal lesions may be transmitted along with cell proliferation.

Animals↗
PubMed1993

Targetted phototherapy with sensitizer-monoclonal antibody conjugate and light.

Photodynamic therapy (PDT) was performed in vitro and in vivo using monoclonal antibody conjugated to hematoporphyrin (HP). The antibody (45-2D9) recognized a cell surface glycoprotein on cells derived from NIH 3T3 cells which were transformed with the ras oncogene (45-342). Radionuclide imaging with either In111 or I125 chelated to 45-2D9 or the isotype identical (IgG1) antibody MOPPC-21 revealed selectivity of 45-2D9 for 45-342 flank tumours in nude mice, and minimal targetting for a 45-342 clone which did not express the cell surface glycoprotein. The 45-2D9-HP conjugate resulted in selective killing of the 45-342 line compared with the parent line in vitro. At HP concentrations of 76 micrograms ml-1, the 45-2D9-HP conjugate resulted in significantly more long-term cures of PDT treated flank tumours compared with free HP at the same concentration. 45-2D9 alone had no effect on tumour growth. The antibody-HP conjugate resulted in significantly less local toxicity compared with standard Photofrin II PDT, and also achieved a greater number of long-term cures. This 'photoimmunotherapy' demonstrates the ability to treat established tumours with greater efficacy and decreased morbidity, probably due to specific sensitizer targetting which allows normal surrounding tissue to be spared upon illumination.

3T3 Cells↗
PubMed1993

Vascular malformation of the internal auditory canal.

A report of a case with a vascular malformation of the internal auditory canal (IAC) is presented. A review of the literature of this rather rare lesion is also made in an attempt to outline its clinical features, radiological diagnosis and management. The differential diagnosis and distinction between vascular malformations and other internal auditory canal tumours are discussed.

Adult↗
PubMed1993

Petrous bone cholesteatoma.

Petrous bone cholesteatoma is a rare pathologic entity and may be a difficult surgical challenge because of potential involvement of the facial nerve, carotid artery, dura mater, otic capsule, and risk of cerebrospinal fluid leak. The objective of this article is to present a personal classification of petrous bone cholesteatomas, a survey of recent surgical attitudes, and our present surgical strategy based on our experience with 54 operations between 1978 and 1990. Radical petromastoid exenteration with marsupialization and the middle cranial fossa approach were used only for small pure infra- or supralabyrinthine cholesteatomas, respectively. The enlarged transcochlear approach with closure of the external auditory canal was used for infralabyrinthine, infralabyrinthine-apical, and massive petrous bone cholesteatomas. Five cases with petrous bone cholesteatomas in different locations are described in detail to present the signs and symptoms together with the management.

Journal Article↗
PubMed1993

Mitotic activity in colorectal mucosa of healthy subjects in two Italian areas with different dietary habits.

The proliferative activity was evaluated in colorectal biopsies of 39 healthy subjects living in two distinct geographical areas, Trieste in northern and Florence in central Italy. Subjects living in Trieste had a significantly higher mitotic activity compared with subjects living in Florence (mitoses/cells counted x 100 were 0.17 +/- 0.04 in Trieste and 0.089 +/- 0.02 in Florence). The results of a dietary questionnaire also showed that subjects in Trieste consumed significantly fewer starches, fibers, nitrites, and proteins. However, no correlation was evident between the consumption of these nutrients and intestinal proliferation.

Adult↗
PubMed1993

The micronucleus assay in mouse peripheral blood reticulocytes demonstrates the transmission of chromosomal instability induced by mitomycin C and benzo[a]pyrene.

The frequency of micronuclei (MN) in mouse peripheral blood reticulocytes supravitally stained with acridine orange was assessed at different time intervals after treatment in vivo with two dose levels of mitomycin C (MMC) and benzo[a]pyrene. Increased frequencies were observed for many days after treatment, indicating that MN may be produced as a consequence of chromosomal instability transmitted by proliferating erythroblasts. These results confirm previous evidence of the persistent cytogenetic effects of MMC and suggest that clastogenic agents acting by different primary lesions may have a similar ability to induce this effect.

Animals↗
PubMed1993

A quality control system involving peer review of abnormal cervical smears.

An internal quality control system which is used in the centralized cytology laboratory of a population-based cervical cancer screening programme in Florence is described. It includes a peer review procedure. Abnormal cervical smears are circulated among all the cytologists and a consensus on the final diagnosis is reached. This daily procedure is designed to evaluate the performance of each cytologist and of the laboratory as a whole but can also be considered a valuable training opportunity. During an 18-month period 1197 smears were reviewed by 15 readers using a reporting form with six main categories of reporting (from 'negative' to 'invasive carcinoma'), plus an 'unsatisfactory' category. Overall the concordance between the 15 cytologists, assessed using the kappa statistic (range 0.46-0.71; median 0.60), was good. The level of agreement increased when a weighted kappa statistic (range 0.55-0.78; median 0.68) was used. Kappa values were also calculated for specific categories and suggested an increasing concordance with increasing severity of the lesions, the categories of 'severe dysplasia' and 'invasive carcinoma' showing the highest agreement. The poor results for the 'moderate dysplasia' confirmed the need for combining this group with the 'severe dysplasia', as proposed in the Bethesda system.

Female↗
PubMed1993

Collagen gene expression and wound strength in normal and radiation-impaired wounds. A model of radiation-impaired wound healing.

BACKGROUND: Poorly healing wounds result in significant morbidity postoperatively. Numerous attempts have been made to study wound healing in vivo to understand better the normal healing process and factors that impair healing. Animal models of wound healing have been developed to evaluate wound healing in a systematic and controlled setting. Incisional wounds are created in animals to mimic the surgical patient. They may then be evaluated by a variety of methods for degree of healing. OBJECTIVE: To give insight into the mechanisms of wound healing impairment, we developed a model of impaired wound healing in guinea pigs using radiation applied to the skin surfaces only. METHODS: Wound bursting strength, a direct measure of the force required to burst apart healing linear incisions, was measured. Collagen content, measured indirectly as collagen gene expression, was measured. RESULTS: Significant reductions in wound bursting strength were noted after radiation administration. Collagen gene expression was decreased in wounds 7 days after radiation, but recovered to control levels 14 days after irradiation. Our model enables the inclusion of irradiated and unirradiated skin flaps within the same animal, thus eliminating intra-animal variation when comparing impaired and normal wounds. CONCLUSION: Wound bursting strength analysis, combined with techniques aimed at elucidating changes at the molecular level, provides a useful tool for the study of factors that impair healing and potential treatments for resulting healing deficits.

Animals↗
PubMed1993

Gastrointestinal function in chronic radiation enteritis--effects of loperamide-N-oxide.

The effects of loperamide-N-oxide, a new peripheral opiate agonist precursor, on gastrointestinal function were evaluated in 18 patients with diarrhoea caused by chronic radiation enteritis. Each patient was given, in double-blind randomised order, loperamide-N-oxide (3 mg orally twice daily) and placebo for 14 days, separated by a washout period of 14 days. Gastrointestinal symptoms; absorption of bile acid, vitamin B12, lactose, and fat; gastric emptying; small intestinal and whole gut transit; and intestinal permeability were measured during placebo and loperamide-N-oxide phases. Data were compared with those obtained in 18 normal subjects. In the patients, in addition to an increased frequency of bowel actions (p < 0.001), there was reduced bile acid absorption, (p < 0.001) a higher prevalence of lactose malabsorption (p < 0.05) associated with a reduced dietary intake of dairy products (p < 0.02), and faster small intestinal (p < 0.001) and whole gut transit (p < 0.05) when compared with the normal subjects. There was no significant difference in gastric emptying between the two groups. Treatment with loperamide-N-oxide was associated with a reduced frequency of bowel actions (p < 0.001), slower small intestinal (p < 0.001), and total gut transit (p < 0.01), more rapid gastric emptying (p < 0.01), improved absorption of bile acid (p < 0.01), and increased permeability to 51Cr EDTA (p < 0.01). These observations indicate that: (1) diarrhoea caused by chronic radiation enteritis is associated with more rapid intestinal transit and a high prevalence of bile acid and lactose malabsorption, and (2) loperamide-N-oxide slows small intestinal transit, increases bile acid absorption, and is effective in the treatment of diarrhoea associated with chronic radiation enteritis.

Adult↗
PubMed1993

Atypical presentation of acoustic neuroma.

Unilateral progressive sensorineural hearing loss, tinnitus, and unsteadiness are the usual initial symptoms of acoustic neuroma. Of the last 100 consecutive cases of acoustic neuroma detected at our Centre, 14 had atypical symptoms, Five patients manifested sudden hearing loss; one of these had complete recovery. Three patients reported long-standing unilateral hearing loss, ranging from 10 to 20 years. Six patients had normal hearing, one of whom was diagnosed incidently when the investigations were performed for contralateral glomus tumor. A second patient, a young woman, experienced weakness of lower limbs. The remaining four patients had only subjective symptoms of hearing loss or tinnitus. Acoustic tumors could have been overlooked easily in these patients. It is important to have a high index of suspicion in all cases of sudden hearing loss, asymmetric sensorineural loss of any duration, subjective sensation of hearing loss, and tinnitus. It is mandatory to investigate these cases with auditory brainstem responses, any abnormality of which makes it necessary to perform magnetic resonance imaging with gadolinium.

Adolescent↗
PubMed1993

Left atrial thrombus and spontaneous echo-contrast in nonanticoagulated mitral stenosis. A transesophageal echocardiographic study.

OBJECTIVE: The aim of the study was to investigate if evidence at transthoracic echocardiography (TTE) of left atrial (LA) thrombus and LA spontaneous echo-contrast (LA SEC), which are potential precursors of embolization, can be predicted by clinical and TTE variables in nonanticoagulated mitral valve stenosis (MS). DESIGN: Clinical (age, NYHA class, rhythm, previous embolization) and TTE variables were related to transesophageal echocardiography (TEE) evidence of LA thrombus and/or LA SEC. SETTING: Nonanticoagulated MS was the setting. PATIENTS: Fifty-nine patients had MS, and they were not receiving anticoagulant or antiplatelet therapy (24 in sinus rhythm and 35 in atrial fibrillation). Previous arterial embolization had occurred in 12 patients (20.3 percent). MEASUREMENTS: The following TTE variables were analyzed: mitral orifice area (pressure half-time method), mitral gradient (Bernouilli's equation), LA end-systolic area, and mitral regurgitation (color Doppler grading). LA thrombus and LA SEC were analyzed by monoplane TEE. RESULTS: LA thrombus was found by TEE in 12 patients (20.3 percent). Of these 12, 11 (91.6 percent) were in atrial fibrillation. LA SEC was found by TTE in 2 patients (3.5 percent) and by TEE in 40 (67.8 percent) (p < 0.001). Previous embolization had occurred only in patients with LA SEC, of whom 5 had and 7 did not have LA thrombus. Patients with LA SEC, compared with those without LA SEC, were characterized by more frequent advanced NYHA class, atrial fibrillation, smaller mitral valve area, and larger LA size. By multivariate regression analysis, atrial fibrillation and LA end-systolic area were factors related to both LA thrombus and LA SEC, whereas mitral area was related only to LA SEC. However, whereas LA SEC was accurately predicted by the presence of atrial fibrillation (sensitivity: 87.5 percent; specificity: 100 percent) and a LA area > or = 30 cm2 (sensitivity: 72.5 percent; specificity: 89.5 percent), among patients with LA SEC no clinical or TTE variable accurately identified those with actual LA thrombus. CONCLUSIONS: TEE is not necessary in many patients with MS in order to recognize LA SEC. However, when actual LA thrombus detection is necessary for clinical decision making, TEE should be performed.

Adult↗
PubMed1993

Keratins 6, 13 and 19. Differential expression in squamous cell carcinoma of the head and neck.

One hundred forty-one head and neck squamous cell carcinomas were analyzed for keratin (K) 6, 13 and 19. Staining was evaluated by light microscopy (with or without grading) and image analyzer and expressed as a percentage of positive versus all tumor surface (PSA). Both techniques rendered strongly correlated results. Strong expression was noted in 108 carcinomas (76.1%) for K6, in 18 (12.7%) for K19 and in 21 (14.8%) for K13 (P = .001). One hundred thirty-six (96%) tumors were positive for K6, and their PSA ranged from 0.6% to 48.8%; K19, 48 cases (0.2-44%); K13, 59 (0.2-38.1%). Expression of K6 was related to differentiation. K19 was expressed mainly in moderately and poorly differentiated tumors, and K13 was manifest more in well-differentiated carcinomas or in keratinized areas of less-differentiated ones. Nineteen (13.38%) tumors were positive for both K13 and K19. K19 thus was related to tumor progression and K13 to differentiation. There was no correlation with tumor site or TNM category.

Adult↗
PubMed1993

[Comparison of magnetic resonance (0,5 T), computed tomography, and endorectal ultrasonography in the preoperative staging of neoplasms of the rectum-sigma. Correlation with surgical and anatomopathologic findings].

Eighteen cases of rectal carcinoma were staged preoperatively with transrectal endosonography (EUS), CT and MRI (0.5 T). The results were compared with surgical specimens and histology to evaluate the accuracy of the imaging modalities in staging rectal carcinomas which had been quantified according to Astler-Coller's classification. All methods identified the lesion (100% sensitivity). EUS and MRI correctly staged 8 cases (44%) and CT 9 cases (50%). CT and MRI mistakes were relative to overstaging, whereas EUS understaged 4 cases (22%) and overstaged 6 cases (33%). In local tumor staging ("T" variable), CT and MRI understaged no lesions, thus exhibiting 100% sensitivity, which was higher than EUS sensitivity (92%). Conversely, CT and MRI more frequently overstaged the lesions, thus demonstrating lower sensitivity than EUS (55% and 50%, respectively, versus 76% for EUS). As for the "N" variable, EUS identified node metastases in one case only (25%) and misdiagnosed as positive 4 cases of negative node involvement. All the C-stage lesions were correctly diagnosed by CT and MRI (whose findings were in agreement) which also overstaged as C three cases with hyperplastic node enlargement. The diagnostic accuracy of EUS, which was highest for the A and B1 stages, progressively decreased for bigger lesions, clearly understaging node involvement. On the contrary, CT and MRI accuracy rates were lower in small tumors involving the rectal wall only, whereas they always identified tumor spread beyond the bowel wall into perirectal fat, and node metastases. Therefore, to conclude, EUS can be used first: in case of extraluminal tumor spread, CT is the method of choice, more accurate than MRI in identifying node involvement and equally effective in evaluating perirectal fat infiltration and pelvic structures involvement. Whenever the pelvic floor is involved, MRI is the best imaging method, thanks to its multiplanar capabilities, for better detailing of musculoskeletal involvement.

Aged↗
PubMed1993

Results of the combination of cisplatin, adriamycin and cyclophosphamide in the treatment of ovarian carcinoma.

Forty-seven women affected by Stage Ic-IV epithelial carcinoma of the ovary were treated with the combination of cisplatin, adriamycin (40-50 mg/m2 day 1), and cyclophosphamide (800 mg/m2 day 1) (CAP). Two different schedules of cisplatin were used: 20 mg/m2 day 1-->5 (CAP 5), or 80 mg/m2 on day 1 (CAP 1). In the group of patients with measurable disease the overall response rate was 52%, with a 19% complete response rate. The mean disease-free survival of patients without measurable disease was 24.0+ months. The mean survival of the whole group was 29.2+ months. The mean survival of patients with measurable disease and those without measurable disease was 21.7+ and 35.0+ months respectively. The schedule of cisplatin employed did not influence disease-free survival since the difference between the CAP 1 (21+ months) and the CAP 5 (25+ months) groups was not statistically significant. However the CAP 5 schedule seemed to be better tolerated since it of allowed the delivery be 99% of the planned dose of CDDP, while in the CAP 1 group the dose of CDDP given was only 74% of that planned.

Adult↗
PubMed1992

In vivo and in vitro growth-inhibitory effect of bovine seminal ribonuclease on a system of rat thyroid epithelial transformed cells and tumors.

We investigated the antitumoral effect of bovine seminal RNase (BS-RNase) in vivo and in vitro on a model system of epithelial tumor- and metastasis-derived cells as well as on epithelial tumors derived from the same system. We found that while BS-RNase significantly inhibited the growth in vitro of the epithelial tumor-derived cells, its inhibitory effect was even more dramatic on the growth of metastasis-derived cells. BS-RNase exerted no appreciable growth inhibition on normal thyroid epithelial cells. When administered in vivo to rats bearing solid carcinomas, having the same thyroid origin, BS-RNase induced a drastic reduction in the tumor weight, with no detectable toxic effects on the treated animals. These data show, for the first time on a system of neoplastically transformed epithelial cells, that BS-RNase has a potent specific antitumoral activity.

Animals↗