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Biomedical subjects

R Foroni

Publications and source records attributed to R Foroni.

At least 37 records · Page 2Linked to original sources
PubMed1995

Gamma Knife stereotactic radiosurgery of ocular metastases: a case report.

A case of a choroidal metastasis treated with Gamma Knife stereotactic radiosurgery is reported. A 48-year-old Caucasian man afflicted with lung cancer (adenocarcinoma) was referred to the University Hospital of Verona, Italy, for loss of vision in his left eye due to a choroidal mass with exudative retinal detachment. Clinical investigation was conclusive of a well-defined, bilobed choroidal metastasis located in the temporal and inferior portion of the posterior pole of the eye. The lesion was characterized by a maximum thickness of 5.2 mm and a maximum lateral extension of 14 mm. The staging was negative for other metastatic localizations. Using the Gamma Knife technique, a surface dose of 25 Gy was administered at the 50% isodose line using the 8-mm collimator (5 shots) with equally weighted fields. After a 3-month follow-up period, a marked reduction in the lesion size as well as in the exudative retinal detachment was observed. This improvement was unchanged 6 months after the treatment, and the lesion appeared completely controlled. To the best of our knowledge, this is the first case report of an ocular metastasis treated with stereotactic Gamma Knife radiosurgery.

Adenocarcinoma↗
PubMed1995

A euristic approach to the volume reconstruction of arteriovenous malformations from biplane angiography.

Three-dimensional (3D) volume reconstruction is easily feasible with axial, coronal or sagittal CT and MRI scans. On the other hand, radiosurgical treatment of arteriovenous malformations (AVMs) is exclusively based on two orthogonal stereotactic projections, obtained with angiographic procedures. Most commonly AVM volumes have been calculated by assimilating the nidus volume to a prolate ellipsoid. We present an algorithm dedicated to 3D volume reconstruction starting from two stereotactic orthogonal projections. This has been achieved using a euristic approach which has been widely adopted in the artificial intelligence domain. Tests on phantoms of different complexity have shown excellent results. The importance of the algorithm is considerable. Firstly, it allows calculations of complex structures far removed from a regular ellipsoid. Secondly, it permits shape recovery. Thirdly, it provides AVM visualization on axial planes.

Algorithms↗
PubMed1995

Quality assessment of magnetic resonance stereotactic localization for Gamma Knife radiosurgery.

Artifacts in magnetic resonance imaging (MRI) may lead to anatomical distortion and inaccurate stereotactic coordinates. A special phantom for MRI and computed tomography (CT) was built to test the quality and precision of the two neuroradiological procedures. The phantom is fixed with the Leksell frame, and it has 15 orthogonal markers visible by CT and MRI techniques. The coordinates of the markers were calculated first on the CT scans and then on MR images. Two groups of different distortions were analysed: artifacts depending on the frame and its components and artifacts depending on the MR unit and image characteristics. A good target-coordinate correlation was found between CT and MRI in the axial plane, while in the coronal plane there was always a small error. This error is not constant, but changes from test to test, consequently it is hard to reform the image.

Artifacts↗
PubMed1994

Cytoreductive effects of anti-transferrin receptor immunotoxin in a multicellular tumor spheroid model.

We have evaluated the sensitivity to immunotoxins (IT) of monolayer and of 200-250 microns multicellular tumor spheroid (MTS) cultures obtained with human breast (MCF7) and glioblastoma (U118) tumor cells and with rat glioblastoma (9L) cells. Monolayer MCF7 and U118 cells were highly sensitive to antitransferrin receptor (anti-TfnR) ricin A chain (RTA)-IT (Tfn-RTA and MAb OKT9-RTA) treatment in the presence of the intracellular RTA-IT enhancing agent human serum albumin-monensin (HSA-Mo) conjugate. A 790- to 2000-fold higher concentration of anti-TfnR IT was instead required to reduce by 50% the volume of individually treated MCF7 spheroids, as evaluated by applying the Gompertz growth model. Monolayer 9L cells showed 230- to 5700-fold lower sensitivity to Tfn-RTA IT than MCF7 and U118 monolayers, yet 9L spheroid cells were almost as sensitive to anti-TfnR IT as monolayer 9L cultures. Binding studies performed with [125I]-Tfn and FITC-labelled anti-TfnR MAb revealed that 9L monolayers and MTS expressed 4.1-fold and 8.8-fold lower amounts of TfnR than MCF7 monolayers and MTS, respectively. However, Tfn bound to TfnR sites of 9L and of MCF7 cells with comparable affinity. Experiments carried out with the diphtheria toxin mutant CRM107 linked to Tfn confirmed the pattern observed with RTA-IT. Monolayers and spheroids showed no considerable differences in sensitivity to ricin toxin. Collectively, these results indicated that the efficacy of IT against 3-D tumors is heavily influenced by the number of target Ag expressed by the tumor cells, as well as by the affinity of IT/toxin-cell interaction.

Animals↗
PubMed1993

New compartmental model approach to dialysis.

Compartmental models are used for solving the problem of the control of dialysis therapy. The inadequacy of the existing monocompartmental model is faced, first with a careful analysis of the physiology of the system, then with a method focused on the construction of a new multicompartmental model. Moreover, impedance techniques allow us to solve the problem of measuring the total body water for each patient.

Body Water↗
PubMed1991

The exponential-Gompertzian tumor growth model: data from six tumor cell lines in vitro and in vivo. Estimate of the transition point from exponential to Gompertzian growth and potential clinical implications.

The published growth data were examined for six tumor cell lines (FSA, Line 1, MCA-11, EMT6/RO, MGH-U1, MLS) grown in vivo and in vitro as monolayer cultures and as multicell spheroids cultured under different experimental conditions. Serial estimates of tumor sizes were fitted by Gompertzian equations obtained with a non-linear computerized program. When the growth equations of the same tumor growing in different experimental conditions were compared, the Gompertzian parameters alpha 0 (initial specific growth rate) and beta (retardation factor) showed a strong linear correlation in all the examined lines, with no exception. This occurrence supports the exponential-Gompertzian growth model, where an early exponential phase (which is virtually not influenced by exogenous factors) is followed by a Gompertzian phase, the characteristics of which are greatly dependent on environmental conditions. The transition between the two phases was estimated to occur when tumor size reached 10(2)-10(4) cells, depending on the cell line. This kinetic change in tumor growth may be clinically relevant as regards cytotoxic treatments. It could explain some consequences of delays in adjuvant (postoperative) chemotherapy observed in clinical trials on primary breast cancer.

Animals↗
PubMed1990

Extramedullary plasmacytoma of the testicle. Sonographic appearance and ultrasonically guided biopsy.

Extramedullary plasmacytomas of the testis are extremely rare. This is a report of a patient with plasmacytoma of the testicle who also had an extramedullary plasmacytoma of the epipharynx 12 months earlier. Sonography (US) scans showed a heterogeneous mass of the right testicle with hypoechoic echo pattern; ultrasonically guided fine-needle aspiration biopsy (UGFNAB) allowed confirmation of the diagnosis. Immunoperoxidase studies, performed on histologic specimen after a radical right orchiectomy showed a monoclonal staining pattern of intracellular immunoglobulin for IgA-K type. Bone marrow biopsy, skeletal X-ray and immunoelectrophoresis were all within normal limits. The patient was successfully treated by surgery and is still alive with no evidence of disease.

Aged↗
PubMed1990

Cardiovascular stability during the haemodialysis session: relationship between modelling and impedance parameters.

The percentage of body water, if calculated from impedance, was found to be significantly different from the classic 58%. This supports the view that the evaluation of the dialytic efficiency should be, in the near future, carried out on the basis of a 'two-pool' model instead of the old 'one-pool'. The serial collection of data during a dialytic session supported the hypothesis that, 90 min after the start or, in general, after a body-water loss of about 5%-6%, some fundamental changes in measured indexes (phase angle, systolic pressure, body volumes, correlation matrix) usually appear. Large-scale research, based on an RS 232 interface connected to a computerised program, will probably help in clarifying whether some major intra-dialytic phenomena could in the near future be easily and automatically predicted.

Body Water↗
PubMed1989

An exponential-Gompertzian description of LoVo cell tumor growth from in vivo and in vitro data.

The data of nine monolayer cultures, 48 multicellular spheroids, and 19 s.c. xenografts of LoVo cells were fitted, on an individual basis, by exponential and Gompertzian equations, respectively. The mean growth parameters alpha 0 (initial growth rate) and beta (retardation factor) of the three experimental systems presented a strong linear correlation alpha 0 = 6.88 beta + 0.56, r = 0.9843. This implies that, at the particular tumor size of 155 microns in diameter (mean +/- SD = 50-310 microns), the tumor growths described by Gompertzian curves (from spheroids as well as from s.c. xenografts) have the same growth rate as monolayer cultures. This occurrence strongly supports an exponential-Gompertzian growth model, where an exponential monolayer-like phase changes to a Gompertzian growth, controlled by environmental conditions, when the tumor size has reached a critical value.

Carcinoma↗
PubMed1989

Relative role of host and tumor in the growth pattern of murine and human neoplasms following subcutaneous transplantation in mice.

The growth patterns of two murine and eight human tumors, bilaterally implanted into subcutaneous tissue of groups of recipient mice, were studied. A Gompertz equation was fitted to experimental data for each individual implant and the Gompertz parameters were utilized as quantitative growth characteristics. The relative roles of the tumor-implanted flank (right versus left), of the individual host and of the tumor were analyzed by the paired t-test, simple linear regression model, one-way and two-way analysis of variance. Sixty pairs of Gompertz curves were obtained in seventy animals. Heterogeneity was the main characteristic of the growth pattern in all tumors under study, with a wide variability among the Gompertz parameters. Statistical analysis of experimental data showed that only the tumor systematically influenced the growth characteristics, whereas neither the tumor-implanted flank nor the individual host played a significant role. These results have both theoretical and practical implications.

Analysis of Variance↗
PubMed1988

Influence of tumor growth kinetics on response to doxorubicin treatment of C3H mammary carcinoma.

The influence of tumor growth kinetics on response to doxorubicin treatment of C3H mammary carcinoma was investigated. Gompertzian growth curves were obtained for the tumor mass of each mouse by a computerized best fit program. The response was assessed by evaluating: a) the total clonogenic cell reduction as a fraction of the initial tumor volume or the tumor volume that should result at the end of treatment in a free growth condition, and b) the partial clonogenic cell reduction at each drug administration, assuming a first order cell kill hypothesis. Slowly growing tumors at each dose level showed a significantly poorer response than rapidly growing tumors. Each response index exhibited a linear correlation with the specific instantaneous growth rate at the time of treatment. Data also suggested a dose-response dependence.

Animals↗
PubMed1988

Chronobiological variations of prolactin (PRL) in chronic renal failure (CRF).

During a 24-hour period, the serum levels of prolactin (PRL) were determined in 89 subjects, including 24 controls and 65 with chronic renal failure (CRF), divided into groups according to sex, age and serum creatinine. In mild CRF, both in males and females, PRL level proved to be higher than controls while its circadian rhythm of secretion disappeared. The MANOVA analysis (multivariate analysis of variance) showed that all 3 considered factors (sex, age, creatinine) have a systematic effect on PRL values, that of creatinine being the most prominent. With the progression of renal failure, the physiological PRL oscillations tended to diminish. In general, increasing creatinine levels progressively shifted the acrophase (that is the time-distance between a given hour and the maximum peak of the function) to the morning, with hemodialysis patients showing acrophases between 12 p.m. and 1 a.m. It is possible that in CRF the PRL feedback system could no longer function.

Adolescent↗
PubMed1986

Analysis of free growth and post-treatment regrowth of C3H mammary carcinoma in individual mice.

Free growth and post-Doxorubicin treatment regrowth of the C3H mammary carcinoma were analysed in individual mice. In both cases, the Gompertzian function provided a better fit than the exponential function, and the difference was statistically significant (P less than 0.001, chi 2 test). No comprehensive Gompertzian function was found, and each individual tumour growth or regrowth was described by a specific curve. Nevertheless, although both individually measured alpha 0 and beta, Gompertzian parameters varied from one animal to another, in both free-growing and post-treatment regrowing tumours a strong linear correlation between alpha 0 and beta was found. A parallelism test was performed to verify if there exists any treatment-induced alteration. The two regression lines appeared to be identical, however.

Animals↗
PubMed1985

Pharmacologic data and technical feasibility of intraperitoneal doxorubicin administration.

Seventy intraperitoneal administrations of doxorubicin were performed in 12 patients with malignant disease in the abdominopelvic space. Peritoneal and hematologic drug levels were measured by fluorimetric assay. A first-order decline in the peritoneal level was determined (T 1/2 96 +/- 18 min), with a mean drug absorption of 84% in 4 h (range 40-96%) and a mean ratio of a peak dialysate/peak serum level of 111 (range 12-390). Gastrointestinal toxicity was common and peritoneal phlogosis occurred twice. The doxorubicin level and the time of peritoneal exposure seem to be critical factors for major local toxicity. At a moderate concentration doxorubicin can be intraperitoneally administered, but its usefulness is probably confined to patients with minimal abdominal disease.

Abdominal Neoplasms↗
PubMedDate not supplied

Intermittent venovenous hemofiltration as a chronic treatment for refractory and intractable heart failure.

Chronic heart failure (HF) is considered to be refractory when persisting despite an intensive drug regimen, or intractable when requiring "artificial" supports. Among them, hemofiltration (HE) has been used frequently, but only on an "acute" basis, to induce fast and safe water removal. Since 1985 the authors have treated refractory and intractable HF first by means of acute CAVH (continuous arteriovenous HE: 11 patients) and then (1988-1992) with IVVH (intermittent venovenous HE), initially done on an "acute" basis (13 patients) and then an a chronic basis (CIVVH): 8 subjects (6M, 2F; mean age, 60.8 years), 3 with RCHF and 5 with ICHF. This report deals with our experience in CIVVH. All patients were in severe failure. During a follow-up period of 63 months (range, 1-17/patient), 82 IVVH treatments (10.2/patient) were carried out, using this schedule: permanent Tesio catheter in superior vena cava, 0.6 m2 filter, double blood pump (blood flow = 80-250 ml/min); transmembrane pressure = 50-150 mmHg; mean ultrafiltration = 19 ml/min; replacement fluid = 8.6 ml/min; and session time = 340 +/- 88 min, according to individual dry weight (bioimpedance system). Six patients died (1-13 months after IVVH began); four of six had ICHF and two of six had RCHF; five of eight patients showed a significant amelioration of functional state, changing from fourth to third, to second and first degree failure, but this was after heart transplantation. In all cases a marked reduction in the drug regimen and in hospitalization was the rule.

Adult↗
PubMedDate not supplied

Primary lymphoma of the spleen. Report of a case with diagnosis by fine-needle guided biopsy.

Primary splenic lymphoma is a relatively infrequent disease; the diagnosis of this entity is currently made with splenectomy. In a 52-year-old female with left upper quadrant abdominal pain, ultrasound showed a normal-sized spleen with an internal hypoechoic focal lesion. Ultrasonically-guided fine-needle aspiration and tissue core biopsy of the splenic lesion showed non-Hodgkin's lymphoma (NHL). At the time of presentation there was no evidence of involvement of lymph nodes, bone marrow or any other organ. A diagnosis of primary splenic non-Hodgkin's lymphoma was made and the patient underwent laparotomy with splenectomy. Histologic examination of the spleen confirmed the diagnosis: low-grade NHL confined to the spleen. The patient is well and in complete remission seven months after diagnosis. The purpose of this paper is to report a rare occurrence of primary splenic lymphoma and to demonstrate the possibility of making this diagnosis by percutaneous guided biopsy.

Biopsy, Needle↗