Ultrastructural alterations in ovaries from nifurtimox or benznidazole-treated rats: their relation to ovarian nitroreductive biotransformation of both drugs

Chagas' disease is a parasitic chronic condition affecting several million people in Latin America. Two drugs are used in the chemotherapy of Chagas' disease: nifurtimox (Nfx) and benznidazole (Bz). Both are nitroderivatives whose deleterious effects are related to their reductive biotransformation. In this work we report that rat ovaries exhibited Bz and Nfx nitroreductase activity. The Bz nitroreductase was only found in the mitochondrial fraction and was partially inhibited by CO. The Nfx nitroreductase activity was maximal in ovarian mitochondria but was also present in microsomes and in the cytosol. The microsomal enzyme was completely inhibited by CO while that in mitochondria was only partially inhibited by CO. The cytosolic activity only proceeded using hypoxanthine as substrate and was inhibited by allopurinol. The cytosolic activity was able to proceed in part under oxygen. All the other Bz or Nfx nitroreductases were completely inhibited by atmospheric oxygen. The potential participation of cytochrome P450, flavoenzymes, iron-sulfur-protein, and xanthinooxidase in both nitroreductive processes is discussed. The administration of either Nfx or Bz to female rats produced ultrastructural degenerative effects in the different cell types of ovaries. Specific alterations such as swelling, disruption, disorganization, and loss of matrix components were observed in ovarian mitochondria. These alterations occurred irrespectively of the ovarian cycle stage. The potential reproductive toxicological consequences of Bz or Nfx administration are analyzed.

Characterization of hamster tumors induced by simian virus 40 small t deletion mutants as true histiocytic lymphomas

Random bred Syrian hamsters given s.c. injections of SV40 small t deletion mutants dl883, dl884, and dl890 rapidly develop reticulum cell sarcomas in the abdominal cavity in addition to slowly developing s.c. fibrosarcomas at the site of virus inoculation. Injection of wild type SV40 s.c. induces only fibrosarcomas at the site of inoculation. In an attempt to understand why mutations in the SV40 small t gene should lead to this difference in tumor-inducing capacity in hamsters, we studied cells from 12 abdominal reticulum cell sarcomas which were induced by the s.c. injection of SV40 mutants. Morphological and functional analyses indicate that these tumor cells are derived from MAC-2+ macrophages. They are highly granulated, vacuolated, and multinucleated, and they generally adhere to glass and plastic. In addition, they (a) phagocytose latex beads; (b) express high levels of class II major histocompatibility complex antigens; (c) contain beta-glucuronidase, acid phosphatase, and fluoride-inhibited nonspecific esterase; (d) contain lysozyme and fibronectin; and (e) express cell surface MAC-2 antigens. Thus, the small t deletions in the SV40 genome appear to permit the virus to transform cells that are distant from the site of virus inoculation; at this distant site, the cells transformed are of a specific lineage, MAC-2+ peritoneal macrophages. This specific tropism may reflect a unique characteristic of MAC-2+ cells or their precursors that renders these cells susceptible to SV40 mutants which are otherwise restricted in the range of cells that they can transform.

Serum and cerebrospinal fluid enzymes in subarachnoid haemorrhage

Serum levels of creatine kinase (CK) and its isoenzyme CK-MB, lactate dehydrogenase (LDH), hydroxybutyric dehydrogenase (HBDH), glutamic oxalacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) were studied in 50 patients with subarachnoid haemorrhage. In 18 cases the cerebrospinal fluid (CSF) was also examined for total concentration of CK and CK-MB. The results were correlated with the degree of neurological deterioration, the angiographic spasm and prognosis. Concurrent increase of CK-MB, LDH and HBDH serum levels indicates a poor prognosis, whereas increase of GOT and GPT does not have clinical significance. High CK-MB levels in CSF were associated with the worst clinical evolution. However, increase of serum enzymes coincided in most cases with the appearance of the spasm. Monitoring of CK-MB, LDH and HBDH serum levels can be useful for following the evolution of the spasm and in predicting the outcome for patients with subarachnoid haemorrhage.

Intraoperative fractures of the femoral diaphysis in hip arthroprosthesis surgery

The authors reviewed 14 cases of fracture of the femoral diaphysis which occurred during 602 hip arthroprosthesis operations. They attempted to ascertain the role of local and general factors in this complication. In 5 cases there was obvious structural alteration in the upper third of the femur with decreased bone resistance; in 5 cases there was abnormal morphology of the diaphyseal canal (morphological incongruence) due to hip dysplasia or previous osteotomy; in 3 cases there was marked dimensional incongruence between the prosthetic stem and the medullary canal and in the remaining case abnormal morphology of the medullary canal was associated with dimensional incongruence. From an analysis of the cases it emerged that complete fractures in cemented arthroprostheses negatively influenced the long-term results while fractures occurring in arthroprostheses with biological fixation do not significantly modify the normal progression. Finally, the authors stress that a careful preoperative evaluation of the radiographs may considerably reduce the incidence of this complication.

Viral gene inhibition of class I major histocompatibility antigen expression: not a general mechanism governing the tumorigenicity of adenovirus type 2-, adenovirus type 12-, and simian virus 40-transformed Syrian hamster cells

The association between the level of class I major histocompatibility (MHC) antigen expression and the tumorigenic phenotype was determined for cells from a series of 15 lines of adenovirus type 2 (Ad2)-, Ad12-, and simian virus 40 (SV40)-transformed hamster cells and 16 lines of cells established from hamster tumors induced by SV40 mutants. These cells range from nontumorigenic to highly tumorigenic in both syngeneic and allogeneic adult hamsters. The Ad2-transformed cells--cells that were nontumorigenic in syngeneic adult hamsters--expressed either high levels or low levels of class I MHC antigens. The SV40-transformed cells--cells transformed in vitro that produced tumors with equal efficiency in both syngeneic and allogeneic adult hamsters--or cells derived from SV40-induced tumors expressed very high levels of class I MHC antigens. The Ad12-transformed cells uniformly expressed low levels of class I MHC antigens; these cells produced tumors 200- to 1,000-fold less efficiently in allogeneic adult hamsters than in syngeneic adult hamsters and produced tumors with about the same efficiency in immunoimmature newborns and immunocompetent syngeneic adult hamsters. We conclude that the expression of either high levels or low levels of class I MHC antigens is, at most, a minor factor in the differences observed among these adenovirus- and SV40-transformed cells in their tumor-inducing capacity in naive, immunocompetent hamsters.

Effects of FCE20700, a new PGE2 derivative, on gastric acid secretion and cytoprotective processes in man

The pharmacodynamic effects of FCE20700, a new PGE2 derivative, have been investigated in 6 healthy volunteers given single intragastric (i.g.) and intraduodenal (i.d.) doses of 1 and 2 mg and placebo, according to a double-blind, within-subjects design. For 30-270 min following i.g. administration the effect of FCE20700 on peptone-stimulated gastric acid secretion (AS) was assessed by i.g. titration, and serum gastrin (G) levels were also determined. For the same period after i.d. dosing the effect of the compound on pentagastrin-stimulated AS and on mucoproteins and bicarbonate content in the gastric juice was measured. Blood pressure (BP), heart rate and possible side-effects were monitored. Following i.g. administration there was a moderate, dose-related, significant inhibition of AS; significant inhibition of G levels was observed only after the highest dose. After i.d. administration there was a very modest though dose-related and significant inhibition of AS; a brief maximal increase in mucoproteins and in bicarbonate levels was apparent after the 1 mg dose. After i.d. but not after i.g. administration of 2 mg there was a modest but significant decrease in BP. No side-effects of clinical relevance were reported. The results appear to suggest a major activity of FCE20700 on cytoprotection rather than in inhibiting gastric acid secretion. The observed change in BP may indicate that after i.d. administration there will be some systemic effects of FCE20700.

Efficacy of biofiltration for intradialytic hypotension

Biofiltration, a simplified variant of hemodiafiltration, relieved intradialytic hypotension and acidosis in three patients previously on conventional hemodialysis.

Adherence of Staphylococcus strains to human urinary and buccal epithelial cells

91 strains of Staphylococci belonging to different species were investigated for their adhesive capacity to urinary and buccal human epithelial cells. Furthermore the adherence of the same bacterial strains was evaluated in relation with their methicillin-sensitive and methicillin-resistant properties. S. aureus showed an high adhesion to buccal and urinary cells; S. saprophyticus and S. epidermidis attached mainly to uroepithelial cells and to buccal cells, respectively. Bacterial strains, either sensitive or resistant to methicillin antibiotic, did not exhibit significant differences of adhesive capacity.

[Phagocytic and intracellular killing activity of rat macrophages: critical analysis of 2 different evaluation methods]

Two different evaluation methods of the "in vitro" bacterial killing activity of macrophages were compared; the former based on the determination of the number of viable microorganisms in the supernatant of macrophage cultures by a microbiological plate method; the latter based on the evidentiation of intracellular killing by differential staining of living and killed microorganisms with acridine orange. Phagocytic and microbicidal activities of peritoneal cells were investigated by the two methods in control rats and in tumor-bearing rats. Qualitative and quantitative differences in the kinetics of phagocytosis and microbial killing were evidentiated in macrophages from tumor-bearing rats. Furthermore, both methods proved to be suitable and reproducible.

Comparison of six systems for the identification of Enterobacteriaceae

Six widely used commercial systems for Enterobacteriaceae identification (API 20 E, API 10, Enterotube, Enterotube II, Micro-ID and Minitek) were evaluated at the same time by testing 611 organisms. Conventional media were used for comparison. API 20 E, Enterotube II and Micro-ID were highly accurate and identified about 91% of the strains to the species level. The remaining organisms required additional tests and only a small minority was misidentified. Percentages of correct identification to the species level were 87.2 for Enterotube, 74.9 for API 10 and 67.1 for Minitek. Enterotube, Enterotube II and Micro-ID were, in our hands, the easiest systems to operate.

[Postoperative analgesia with lysine salicylate and pentazocine]

The analgesic effect of two doses (1.8 and 3.6 g) of acetylsalicylate of lysine and two doses (30 and 60 mg) of pentazocine was studied after random administration to 40 patients who had undergone cholecystectomy. The experimental pattern was a four-point bio-assay and pain intensity was assessed on a 0 to 100 algesimetric scale by the patients themselves upon administration of the analgesic and after 30, 60 and 120 minutes. The analgesic of acetylsalicylate of lysine proved dose-dependent with a power ratio with respect to pentazocine of between 43 and 65.

"In vivo" and "in vitro" effects of a bacterial extract on Herpes Simplex Virus

The present studies were designed to evaluate the effects of substance or substances extracted from Escherichia coli on Herpes Simplex Virus. The "in vivo" assays show that bacterial extract introduced i.p. in mice simultaneously with HSV2 brought about 100% of survival, but the inoculation of crude extract after virus challenge brought about complete mortality of mice. "In vitro" assays show that the crude extract reduced significantly the numbers of PFU; better results were obtained when the crude extract was inoculated before the virus inoculation.