Anti-tumour,toxicological and pharmacokinetic properties of a novel taurine-based nitrosourea (TCNU)

Summary A novel nitrosourea, 1-(2-chloroethyl)-3-[2-(dimethylaminosulfonyl) ethyl]-1-nitrosourea (TCNU) tauromustine, has been investigated in a broad anti-tumour screen and, in depth toxicology and initial pharmacokinetics carried out.TCNU and its two metabolites were found to exhibit equal or better oral efficacy than that of BCNU, CCNU, MeCCNU or chorozotocin against L1210 leukemia, Walker mammary carcinoma, Lewis Lung, Harding Passey melanoma and colon carcinoma C26. The toxicological profile of TCNU after acute and 3 months treatment was similar in mice and rats to that of CCNU, with the exception that, TCNU did not cause the chronic liver disturbances found for CCNU. In dogs treated for 6 weeks with TCNU leucopenia and thrombocytopenia were the major side effects. Parent TCNU was found in all dogs. The absorption was fast, the maximum level being reach after 25 mins and the mean absorption time was 22 mins. The mean half life was 16.1 mins after intravenous and 17.4 after oral administration. The combination of these factors make TCNU an interesting clinical candidate.     

Shigella infection induces cellular activation of T and B cells and distinct species-related changes in peripheral blood lymphocyte subsets during the course of the disease.

Immunophenotypic changes in peripheral blood lymphocytes (T, B, and NK cells) in patients during shigellosis was characterized by using triple-color flow cytometry. Eleven Shigella dysenteriae 1-infected adult patients (SDIP), 11 Shigella flexneri-infected adult patients (SFIP), 15 age- and sex-matched healthy controls from Bangladesh (C-B), and 15 healthy volunteers from Sweden (V-S) were studied. In SDIP and SFIP, a significant increase in the CD45RO+ cells in both CD4+ and CD8+ T cells were seen. We found evidence for sequential T-cell activation, as shown by increased proportions of CD25 and CD4+ cells; HLA-DR and CD38 on CD8+ cells, and CD54 on CD4+ and CD8+ cells. We found differences in the lymphocyte activation and subset patterns related to the infecting Shigella species. Thus, a decrease in CD45 expression was seen in SFIP; this decrease progressed further during the disease. The proportions of NK cells (CD56+ cells) and CD3- CD8+ cells out of the total CD8+ cells were increased in SFIP but not in SDIP. The CD3+ CD8+ CD57+ T-cell subset was significantly lower in SDIP than in C-B. The proportion of B-lymphocyte-expressing activation markers CD80 and CD23 was higher in patients than in C-B. There was a significant increase in the proportion of CD4+ T cells and a significant decrease in the percentages of total B cells, the CD3+ CD8+ CD57+ T-cell subset, and the CD56+ CD16+ NK-cell subset for V-S compared with C-B. Our results indicate that distinct subset changes and activation patterns are elicited in SDIP compared with SFIP and also that the degree of activation is related to disease severity. In addition, a common sequence of cell activation was seen during the disease course. The difference in the subset patterns seen in C-B and V-S may be related to differences in the levels or spectra of infectious agents in the environment.     

Nucleic acid labeling with [3H]orotic acid and nucleotide profile in rats in protein deprivation, enteral and parenteral essential amino acid administration, and 5-fluorouracil treatment

Rats were fed a 0% casein diet for 1 week, with or without enteral or parenteral administration of essential amino acids, or a 25% casein diet, in one group supplemented with 5-fluorouracil treatment. Ninety minutes before sacrifice the rats were given a tracer of [3H]orotic acid. Incorporation into the acid soluble fraction, RNA, and DNA was determined in liver, small intestine, bone marrow, and kidney. Nucleotide profile was examined in liver and intestine. Protein deficiency caused inter alia a decrease in body weight; a decrease in RNA/DNA ratio and an increase in the specific RNA labeling in liver and kidney; an altered nucleotide profile in the liver; an increase in the nucleotide/DNA and RNA/DNA ratios and a decrease in the specific labeling of the acid soluble fraction, RNA, and DNA in the bone marrow. These changes were prevented to the same extent by giving essential amino acids, either orally or intravenously. The minor changes in intestinal nucleotide profile in protein deprivation were prevented to a slightly larger extent by amino acids orally than parenterally. 5-Fluorouracil treatment gave a decrease in the RNA/DNA ratio in the liver and kidney but an increase in the nucleotide/DNA and RNA/DNA ratios in the bone marrow. Nucleotide profiles were unaltered. The amount of DNA per gram of tissue decreased in bone marrow and increased in kidney. Parenteral administration per se resulted in almost no changes.     

Low antibody levels against cell wall-attached proteins of Streptococcus pyogenes predispose for severe invasive disease

Acute-phase serum samples from 70 patients with group A streptococcal (GAS) invasive disease were analyzed for IgG antibodies against 6 recently characterized GAS virulence factors (SclA, SclB, GRAB, MtsA, EndoS, and IdeS) and SpeB. Antibody levels against the cell wall-attached GAS antigens SclA, SclB, and GRAB were significantly lower in patients with severe invasive disease (streptococcal toxic shock syndrome [STSS] and/or necrotizing fasciitis [NF]; n=35), compared with levels in patients with nonsevere GAS bacteremia (n=35). Among patients with severe invasive disease, significantly lower antibody levels against GRAB were found in patients with STSS (n=10) than in patients with NF (n=17). Antibody levels against SpeB in patients with severe bacteremia were similar to those in patients with nonsevere bacteremia, and levels in patients with STSS were similar to those in patients with NF. The data indicate that immunity to cell wall-attached proteins may play a role in the protection against severe invasive disease and that antibodies against GRAB may be of importance in the pathogenesis of STSS.     

Fulminant course of infectious mononucleosis with virus-associated hemophagocytic syndrome

A fatal case of infectious mononucleosis due to serologically verified Epstein-Barr virus infection in a previously healthy 30-year-old man is presented. The clinical course was characterized by severe prostration, persistently high spiking fever, and continuous development of enlarged lymph nodes. Hematologic examination revealed peripheral leukopenia and thrombocytopenia, and in the bone marrow an increased number of benign histiocytes showed marked hemophagocytosis. At autopsy abnormal lymphoid infiltrates were present in several tissues. The pathogenesis of this infection-associated hemophagocytic syndrome is discussed in terms of the possibility of an impaired immune response to infectious agents.     

Induction of proliferation and blast transformation by interferon in human malignant and non-malignant lymph node B cells

The influence of interferon (IFN) on cellular proliferation, blast transformation, and differentiation was studied in lymph node cells from 17 patients with B-cell lymphomas, one patient with T-cell lymphoma, and eight patients with enlarged, non-malignant lymph nodes. The effects of IFN on lymph node cells were compared with effects on mononuclear blood cells from chronic lymphocytic leukemia (CLL) patients and healthy donors. Natural IFN-alpha (nIFN-alpha) induced a proliferative response in cells from seven of 17 of the B-cell lymphomas, in two of eight of the non-malignant lymph nodes, and in lymphoid blood cells from two of 32 CLL patients. With few exceptions, the proliferating cells were B cells and the data suggest that IFN acts directly on the B cells. Proliferation was not induced with IFN in cells from the T-cell lymphoma or in mononuclear blood cells from 13 healthy donors. nIFN-alpha induced blast transformation in cells from ten of 14 of the B-cell lymphomas and in four of seven of the non- malignant lymph nodes. Also beta- and gamma-IFN were shown to induce proliferation and blast transformation in lymph node cells from some patients. No major effect on the expression of various differentiation markers could be observed following culture in the presence of nIFN- alpha. We conclude that IFNs can induce proliferation and blast transformation in malignant and non-malignant B cells from lymph nodes.     

Midwives' experience of organisational and professional change

OBJECTIVE: to describe midwives' experiences of changes in their caring role and professional function in postpartum wards in the northern part of Sweden. In this part of the country, three out of eight maternity departments have been closed over the last 5 years. During the same period, hospital stays have reduced in length, and an early discharge model has been introduced. DESIGN: focus-group discussions. SETTING: four focus groups at two hospitals in northern Sweden. PARTICIPANTS: 21 midwives experienced in midwifery practice in maternity wards. FINDINGS: the analysis revealed four categories of comments: 'to have limited time when caring for the mother and the baby'; 'no longer being valued as the expert'; 'a wish to have responsibility for childbirth in its entirety'; 'to see future possibilities in the development of the profession'. The theme identified is 'being ahead in ideas about caring but still partly caught up in the past'. KEY CONCLUSIONS AND IMPLICATIONS: the identified theme of being ahead in ideas about caring but still partly caught up in the past can be understood as representing a transition. The midwives experienced loss and grief over their former midwifery practice, but had ideas and visions for developing and expanding their future professional role. A healthy transition requires support, participation and skilled management.     

Early and late results of controlled ventilation in flail chest.

From 1967 through 1974, a consecutive series of 35 patients with flail chest were treated with intermittent positive-pressure breathing (IPPB). The controlled ventilation contributed to stabilization of the thoracic cage in a favorable position for healing of the fractures. Surgical stabilization of the chest was not attempted in any of the cases. During treatment with IPPB, one patient died from profuse bleeding due to a generalized coagulation disorder, but the remaining 34 were discharged in a satisfactory respiratory condition. A late follow-up study of the pulmonary function one to eight years after the trauma included x-ray films of the trachea and lungs, kymographic studies of the diaphragm, spirometric and radiospirometric testing, and arterial blood gas levels. Eighteen patients were examined. Spirometric testing revealed astonishingly little impairment of the total pulmonary function. The radiospirometric studies with 133xenon showed a significant reduction of the regional perfusion only in five patients (2 to 4.5 pulmonary segments). Kymographic study of the diaphragm gave no further information and was less selective compared with the other tests of pulmonary function. Owing to the encouraging early and late results in this study, early treatment with IPPB is considered to be the method of choice in flail chest with paradoxic respiratory movements.