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Biomedical subjects

M Santillana

Publications and source records attributed to M Santillana.

6 recordsLinked to original sources

Virus expression in different tissues of normal and tumor-bearing mice inoculated with a murine leukemia virus.

Evolution of virus expression in different lymphoid organs as well as in solid syngeneic tumors of mice inoculated with an MuLV was studied with the aid of in vitro XC co-culture technique. When normal adult mice of strain XLII were inoculated intraperitoneally with a cultured Rauscher virus (RC), the virus could be detected, 10 days after inoculation, only in bone marrow in small amounts and thereafter no virus could be found in any of the organs tested, including bone marrow, spleen, thymus, lymph node and kidney. However, when age- and sex-matched parallel mice bearing syngeneic subcutaneous non-viral tumors were inoculated similarly with the RC virus, the virus could be detected abundantly not only in bone marrow and spleen but also in tumors during the first 3 weeks and even 6 weeks after virus inoculation. Transitional decrease or disappearance of the virus was observed around the 25th-31st day in organs and tumors of the inoculated mice. When the tumor mass was removed from these mice by surgery, the virus disappeared rapidly and definitely from all the organs tested. The virus recovered from in vitro explanted and cultured tumors, taken from mice inoculated with the virus, induced typical lymphoid leukemia in BALB/c mice inoculated as newborns. However, from certain aspects (hypertrophy of the thymus and lymph nodes), this virus was different from the original RC virus.

Animals

Activation of "eclipsed" lymphoid cells from advanced tumor-bearing mice through adoptive transfer to sublethally irradiated syngeneic hosts.

Immunologically inactive or "eclipsed" lymphoid cells from advanced tumor-bearing mice were investigated following their adoptive transfer to irradiated syngeneic hosts. Experiments were performed with two syngeneic tumor-host system: the T5-BALB/c tumor line chronically infected with a low-leukemogenic Rauscher virus variant and the TM1-C3H tumor line developed from a spontaneous C3H/He mouse mammary tumor. In confirmation of our previous data, peritoneal cells (PC) from advanced tumor-bearing mice (EPC) appeared to have lost any capacity to inhibit specifically the growth of corresponding tumor target cells in vitro colony inhibition (CI) tests, whereas PC from immunized mice (IPC) were perfectly active. When these EPC were adoptively transferred by intraperitoneal inoculation into sublethally irradiated (450 R) syngeneic mice in association with respective tumor extracts (TE), the PC from such recipient mice, taken 5 to 13 days later, were nearly as active in in vitro CI tests as were PC from parallel IPC-recipient mice. For this recovery of specific immunological activity following the adoptive transfer of EPC the adjunction of the TE and irradiation of the recipient animals seem important and may be necessary. On the other hand, no specific immunological activity was seen in PC from irradiated mice to which PC from normal mice had been transferred with TE. In addition to the in vitro results, an effect of adoptive transfer of EPC (retardation of tumor growth) was also observed in vivo. It is concluded that the "eclipsed" immunologically inactive state of the EPC in mice bearing advanced tumor is not irreversible and that activation of these cells can occur in vivo under certain conditions helped by the presence of tumor-specific antigenic stimulus.

Animals

Surgical complications of typhoid fever: enteric perforation.

Typhoid fever remains a prevalent disease in developing nations as the result of adverse socioeconomic factors. The most frequent complication, and principal cause of mortality, is perforation of the terminal ileum. This report presents our experience with 96 patients surgically treated at Cayetano Heredia University Hospital in Lima, Peru from 1972 to 1986. The clinical characteristics and the diverse surgical procedures utilized in the management of these patients are reviewed.

Humans