Comparative in vitro microdosimetric study of murine- and human-derived cancer cells exposed to alpha particles.

Diffusing alpha-emitter radiation therapy (DaRT) is a proposed new form of brachytherapy using α particles to treat solid tumors. The method relies on implantable ²²4Ra-loaded sources that continually release short-lived α-particle-emitting atoms that spread inside the tumor over a few millimeters. This treatment was demonstrated to have a significant effect on tumor growth in murine and human-derived models, but the degree of tumor response varied across cell lines. Tumor response was found to correlate with the degree of radionuclide spread inside the tumor. In this work we examined the radiosensitivity of individual cells to determine its relationship to tumor response. Cells were irradiated in vitro by α particles using a ²²8Th irradiator, with the mean lethal dose, D0, estimated from survival curves generated by standard methods. The results were further analyzed by microdosimetric tools to calculate z0, the specific energy resulting in a survival probability of 1/e for a single cell, which is considered to better represent the intrinsic radiosensitivity of individual cells. The results of the study demonstrate that, as a rule, tumors that respond more favorably to the DaRT treatment are also characterized by higher intrinsic cellular radiosensitivities, with D0 ranging from 0.7 Gy to 1.5 Gy for the extreme cases and z0 following the same trend.

The use of induced sputum in the assessment of pulmonary involvement in Crohn's disease.

OBJECTIVE: Our aim was to evaluate lung involvement in Crohn's disease (CRD) patients by induced sputum (IS). Extraintestinal manifestations are frequent in CRD, but lung involvement is rare. Induced sputum is a reliable noninvasive method of investigating the pathogenesis, pathophysiology, and treatment of lung disease. METHODS: Twenty-four CRD patients and nine control subjects (all nonsmokers) without respiratory symptoms were tested. Sputum was induced by 20' inhalation of 3.5% saline using ultrasonic nebulizer. Samples were studied by differential counts of 200 cells on cytopreps stained by Giemsa. T-lymphocyte subset analyses were done by FACS using three monoclonal antibodies: CD3 = total T cells, CD4 = T helper cells, and CD8 = T suppressor-cytotoxic cells. CD4/CD8 >2.5 was considered abnormal. RESULTS: Four patients did not produce sputum. Of the remaining 20 patients, seven had active CRD and 13 were in remission. They were divided into two groups: Group A patients had abnormal CD4/CD8 ratio of 6.7 +/- 2.5; Group B (seven patients) had normal CD4/CD8 ratio of 1.7 +/- 0.52 (p = 0.0001). The differential counts of IS samples were similar in both groups, but lymphocyte count was significantly higher in CRD patients than in the control group (13.2 +/- 11.2 vs 4.8 +/- 3.6, p = 0.036). There were no differences in spirometry, treatment, extent, or activity of CRD. CONCLUSION: Using a simple noninvasive method, we found that among CRD patients without respiratory symptoms there was a high (65%) incidence of lung involvement.

[The conservative treatment and evolution of intermittent divergent strabismus]. / Tratamentul conservator si evolutia strabismelor divergente intermitente.

We study 43 children with intermittent exotropia treated in Eye Clinic, Cluj. 83.7% shows excess divergence exotropia and only 16.3% convergence insufficiency exotropia. The children are treated with optical correction, prisms and orthoptics.

[Clinico-statistical observations on malignant ocular tumors surgically resolved at the Cluj-Napoca Ophthalmological Clinic between 1970 and 1990]. / Consideratii clinico-statistice asupra tumorilor maligne oculare rezolvate chirurgicale în Clinica oftalmologica din Cluj-Napoca între anii 1970-1990.

During the period mentioned above there ware hospitalized 54 patients having epibulbar tumours. The anatomopathological exam which was effectuated for 33 patients hes shown Bowen's disease for 14 cases, spinocellular carcinoma for 15 patients and basocellular for 3 patients. There were 4 cases for epibulbar precancerous. There was retinoblastoma for 19 cases; it had been practiced the enucleation of ocular globe for 17 patients and for two cases it had been practiced the exenteration of the eye socket. At the same period there were 91 uveal melanosis 6 of which having iridial localization, 10 cases of ciliary body [correction of cylar corpus], 75 cases of choroid. The hepatic scintigraphy was practiced for 56 patients and had shown for 8 cases hepatic metastasis. The histopathological exam of the melanomata of ciliary and choroidal corpus had shown type A fusiform cells for 22 cases, type B for 43 cases, epithelioid cells for 6 cases and mixed type cells for 13 cases. The hepatic metastasis were epithelioid cells for all the cases and, for 2 cases there were with mixed type cells, It is necessary an active discovering of intraocular and episcleral malign tumours, for increasing the chance of an earlier diagnosis during a stadium that would be able to be treated as conservator as possible be.