Detection of a complex of SV40 large tumor antigen and 53K cellular protein on the surface of SV40-transformed mouse cells

The possible interaction between simian virus 40 (SV40) large tumor antigen (T-ag) and cellular proteins in the plasma membrane of SV40-transformed mouse cells was investigated. The presence of SV40 T-ag, 53,000 (53K) cellular protein, and histocompatibility (H-2) antigens on the surface of SV40-transformed cells was demonstrated by immunofluorescence. The use of lactoperoxidase-catalyzed cell surface iodination and a differential immunoprecipitation technique established that large T-ag is associated with the 53K host-coded protein on the surface of the transformed cells. In contrast, no detergent-stable complex between large t-ag and H-2 antigens was detected. Both labeled T-ag and 53K protein were coprecipitated from surface-iodinated SV40-transformed cells by monoclonal antibodies directed against either the viral or the cellular protein. Based on the unique antigenic sites recognized by the anti-T monoclonal antibodies, it appears that both the carboxy and amino termini of the T-ag polypeptide are exposed on the surface of SV40-transformed mouse cells. The nature of the association between surface T-ag and 53K protein, as well as that between the molecular complex and the plasma membrane, remains to be determined. The possible effect of the surface-associated T-ag/53K complex on cellular proliferation is considered.

[Newberyte in old calculi of the urinary system]

In 542 old calculi belonging to the collection complied by Dr. P. Cifuentes Díaz, we have found newberyte in 81 calculi (14.9%). Newberyte appears in the struvite and apatite calculi in the form of small crystals looking like a mosaic. This results from the transformation of the struvite when it loses NH3 and H2O which we have only found in old urinary calculi.

Biochemical differences between products of the Adh locus in Drosophila

An analysis of the molecular properties of the major alcohol dehydrogenase (E.C.1.1.1.1.) allozyme variants found segregating in natural populations of D. melanogaster is presented. Our results indicate: (1) ADH-S enzyme has generally lower Michaelis-Menten constants than those of ADH-F; (2) ADH-S and ADH-F enzymes display opposite interactions for both co-factor and substrate; and (3) higher levels of ADH are associated with the Adh-fast genotype. The possible adaptive significance of these findings is discussed.

Experimental colon cancer in the absence of intestinal contents in Sprague-Dawley rats

The proximal and distal ends of the transverse colons of 16 noninbred Sprague-Dawley rats were severed and stitched to their abdominal walls. The ascending and descending colons were anastomosed end-to-end. The disarticulated colon loop was rinsed 30 times over 15 days to remove all traces of dimethylhydrazine (21 mg/kg body wt) for 27 weeks. When rats were killed 3 weeks later, 4 had invasive carcinomas and 2 had tubular adenomas in the end-to-end anastomosed (function-isolated) colons. Three rats developed invasive carcinomas in the isolated (defunctionalized) colon loops. The carcinogen probably reached the isolated colon loop through the circulation and induced (independently of bile acids) mucosal changes that led to invasive carcinoma.

Chemoimmunotherapy with Corynebacterium parvum in acute myelocytic leukemia

The purpose of this study is to see if immunotherapy with C. parvum and prevention of central nervous system relapse with intrathecal methotrexate can prolong duration of complete remission and survival as well as avoid central nervous system relapse. For induction, three weekly I.V. injections of vincristine and Daunorubicin were given with daily prednisone orally, followed by 5-day courses of Cytosine Arabinoside and 6-mercaptopurine. The patients were randomized to chemotherapy or chemoimmunotherapy. Maintenance consisted of vincristine, Daunorubicin, and prednisone one week every odd month, and a 5-day course of Cytosine Arabinoside and 6-mercaptopurine every even month. Every week, the chemoimmunotherapy group also received, without chemotherapy, one injection of C. parvum 4 mg, subcutaneously. All patients received five weekly injections of intrathecal methotrexate 13 mg/m2 right after complete remission was achieved. Out of 181 evaluable cases, 80 (44%) achieved complete remission, 45 were randomized to chemotherapy, and 35 to chemoimmunotherapy. In the chemoimmunotherapy group 32/35 relapsed, and in the chemotherapy group 36/45. Median duration of complete remission and survival were: for group chemotherapy, 8 and 15 months; for group chemoimmunotherapy, 5 and 10 months. This difference is not significant. Intrathecal methotrexate was given to all patients. Six patients (7%) had central nervous system leukemia at the time of the first injection. None had central nervous system relapse after prevention with intrathecal methotrexate. This method seems useful in preventing central nervous system relapse in patients with acute myeloblastic leukemia, but does not seem to prolong complete remission.

Ultrastructural study of apatites in human urinary calculi

Using transmission and scanning electron microscopy, we have studied the ultrastructure of a number of urinary calculi, mainly composed of calcium phosphate. Three fundamental kinds of calcium phosphates were detected: nonstoichiometric carbonate apatite, nonhexagonal octacalcium phosphate, and calcium-magnesium whitlockite. The influence that the organic matter, substitutions in the phosphate lattice of CO3 and Mg, and apatitic stoichiometry have on the ultrastructure of the calcium phosphate calculi has been detailed. An originating apatitic unity named U2 is assumed to be the responsible for all the different structures of calcium apatites appearing in renal calculi. On the basis of our observations, a mechanism whereby apatites grow is postulated; magnesium functions as an inhibitor for the growing mechanism.

Composition of apatites in human urinary calculi

Calcium-deficient carbonate apatites in urinary calculi from 17 patients have been studied. Magnesium ions in each case were detected as a component of apatite. In most of the cases, CO23- ions were included in the apatitic lattice. Using a calcination procedure, we have determined the most probable average value for the CO23- content, degree of deficiency, x, and the Mg/Ca ratio in each sample.

CT studies of the liver in vitro: a report on 82 cases with pathological correlation

Eighty-two liver specimens were studied by both computed tomography (CT) and pathological examination with serial sectioning. In vitro CT studies showed low density structures within 57 normal livers to be due to portal and hepatic vessels but not to bile ducts. A liver with a minimum of 70% fatty infiltration could be diagnosed correctly on CT. Concerning the presence or absence of circumscribed liver disease, sensitivity was 80% and specificity was 84%. With respect to the total number of space occupying liver lesions (n = 364 in 18 specimens), sensitivity was 72%. The smallest metastases detectable on CT were 0.5 cm in diameter, but CT disclosed focal lesions of this small size in only 15% of the cases. In contrast to previously reported in vivo CT studies, metastases were often found to be of higher density than normal liver tissue in vitro.

[Stage I and II cancer of the cervix. Report on the results of treatment in 1,015 patients (author's transl)]

The results of treatment in 1,015 stage I and II patients with cancer of the cervix are presented. The 5 year survival and recurrence rates were calculated in relation to the treatment applied. Two groups of stage Ib and IIa patients were available, one of them having been treated with radiotherapy, and the other one with radical hysterectomy and pelvic lymphadenectomy after previous intra cavitary radiumtherapy. The difference in the survival rates between the two stage Ib groups is not statistically signficant. We did not try to make a statistical comparison between the two stage IIa groups because the combined therapy group includes only patients with very early lesions. Most stage IIb patients were treated with radiotherapy. The postoperative mortality was 2.2%. There were no deaths related to treatment in the group of patients treated with radiotherapy alone. Ninety percent of the recurrences appeared within 3 years after completion of treatment.

Monosodium urate in urinary calculi

In 3,000 calculi, monosodium urate was detected in 50 cases (1.66%). Infrared frequencies of monosodium urate are reported. In thin sections it appeared as long and thin fan-shaped or feather-like arranged crystals. Six calculi had monosodium urate as the sole component but all other cases were of mixed composition, with whewellite as the main secondary substance. The relative scarcity of monosodium urate cannot be explained by its high aqueous solubility because in urine the solubility decreases with increasing sodium concentration. Monosodium urate should be suspected in radiolucent calculi with neutral or light alkaline reaction and high uric acid and sodium concentrations in the patient's urine.