Morphological characterization of lymphoid cells conjugates with scattered tumor target cells in organ imprints of Yoshida ascites bearing rats

The authors analysed morphologically the ability of host effector cells to bind disseminated tumor target cells (pre-lysis) in vivo. Scattered tumor cells are morphologically visible stained with May Grünwald-Giemsa in the lung, liver, kidney, and spleen imprints of Yoshida ascites tumor bearing rats. Lymphoid cells can be seen binding disseminated tumor target cells in organs but not in the peritoneal cavity. This model may provide a useful technique for morphological studies on the in vivo conjugation capacity of host effector cells against tumor target cells.     

Single and combined effects of two trace elements (Cd and Cu) on the asexual reproduction of Aurelia sp. polyps

Aquatic Ecology - Jellyfish blooms are an increasingly common event in our seas. Occurring via polyps’ asexual reproduction induced by human stresses, they represent a hazard for ecosystems...     

Neoplastic cell spreading in rodent transplantable tumor models. I. Ehrlich tumor

Ehrlich ascites tumor cells were ectopically transplanted in femoral muscles of tumor-free Swiss and BALB/c mice with the same modality used for i.p. serial transplantations of the ascitic form. A solid tumor developed (100% takes as i.p. grafts) locally invading surrounding tissues and leading to death within 30-40 days (12-14 days in ascitic form). These animals were killed when showing signs of debilitation by tumor growth (1 mo.). The recipients' own thoracic and abdominal organs (lung, liver, spleen, and kidney plus peritoneal fluid) as well as the solid tumor were removed to obtain imprints and smears fixed and stained for cytology (May Grünwald Giemsa). Tumor-free mice were used as a control and i.p. transplanted mice were sacrificed on day 8. Disseminated tumor cells were seen in recipient organ imprints and peritoneal fluid smears scattered among local normal cells. Host defense cells with prevalence of neutrophils were observed infiltrating the solid tumor or adjacent to disseminated tumor cells. According to previous findings, organ imprints of i.p. transplanted mice showed disseminated tumor cells and host defense cells. Surprisingly, in liver imprints of ectopically transplanted BALB/c mice, numerous megakaryocytes were detected. This tumor and host organ imprint assay offers the possibility to monitor in vivo the phenomenon of metastatic tumor spread.     

Neoplastic cell spreading in rodent transplantable tumor models. II. Santamaria tumor (syngeneic keratinizing squamous cell carcinoma)

A syngeneic transplantable tumor was obtained in our laboratory by inducing a skin squamous cell carcinoma in BALB/c mice treated with benzo(a) pyrene and UVA. Single tumor cell suspensions obtained by finely disrupted tumor masses were either i.p. or intramuscularly injected and developed (100% takes) invasive tumors maintaining in subsequent analogue serial transplantations identical histopathological aspects. May Grünwald Giemsa stained organ imprints of tumor bearing mice showed disseminated tumor cells as well as a number of infiltrating host defense cells (principally neutrophils) despite the mice were in a terminal status. May Grünwald Giemsa stained cryostat sections showed numerous mast cells lining the invasive tumor front and allowed to detect in the liver tumor cells migrated from primary tumor (localized in femoral muscle) adhering to endothelial cells may be to perform extravasation.