Nitrative stress and poly(ADP-ribose) polymerase activation in healthy and gestational diabetic pregnancies.

AIMS/HYPOTHESIS: Increased oxidative-nitrosative stress, poly(ADP-ribose) polymerase (PARP) activation and subsequent cellular damage play important roles in the complications of both diabetes mellitus and pregnancy. Our aim was to investigate nitrative stress and PARP activity levels during normal and gestational diabetic (GDM) pregnancy in both maternal and fetal tissues. METHODS: Blood samples were collected during pregnancy (weeks 16-29 and 36-40), and placental and umbilical cord tissues were harvested after delivery from healthy volunteers and GDM patients subjected to a carbohydrate-restricted diet or insulin treatment. Immunohistochemical staining was performed on leucocytes and tissue sections using anti-nitrotyrosine (NT), anti-poly(ADP-ribose) (PAR) and anti-apoptosis inducing factor antibodies. RESULTS: In healthy pregnancies the intensity of NT and PAR staining of leucocytes correlated positively with gestational week (R (2) = 0.43, p < 0.01 and R (2) = 0.49, p < 0.001, respectively). In patients on a carbohydrate-restricted diet PAR staining was already strong in weeks 16-29 (p < 0.001 vs control) and did not increase further. In weeks 16-29 there was a correlation between PAR staining and the 2 h value of the oral glucose tolerance test (R (2) = 0.49, p < 0.001). Patients with the highest level of leucocyte PARP activity later required insulin therapy, which decreased the intensity of NT and PAR staining. Placental and umbilical cord tissues also had a higher level of nitrative stress markers in GDM pregnancies, but the highest level of PARP activity was observed after insulin therapy. CONCLUSIONS/INTERPRETATION: Continuous elevation of tyrosine nitration and PARP activation may be considered physiological during pregnancy. However, the high level of PARP activity in early pregnancy may signal the subsequent development of severe GDM.

The production of tumor necrosis factor by mouse bone marrow-derived macrophages in response to bacterial lipopolysaccharide and a chemically synthesized monosaccharide precursor.

Lipid X, a monosaccharide biosynthetic precursor of lipid A, has been chemically synthesized and was shown to induce bone marrow-derived macrophages to release tumor necrosis factor (TNF) in vitro. However, relatively high amounts of lipid X were necessary for induction, and the levels of TNF were much less than those induced by small amounts of lipid A itself or LPS. Lipid X prepared by extraction of Escherichia coli mutants induced higher levels of TNF than the chemically synthesized material, but this is probably partially due to amounts of impurities in the extracted material. Pretreatment of macrophages with IFN-gamma resulted in the release of higher amounts of TNF on subsequent induction with either LPS or lipid X. In contrast, pretreatment of macrophages with LPS induced hyporesponsiveness for TNF production on subsequent rechallenge with LPS. Lipid X, on the other hand, was incapable of making macrophages hyporesponsive for TNF production.

Codex committee on veterinary drug residues.

There has been widespread international concern over residues of veterinary drugs in food. However, until recently, there was little international cooperation in trying to find solutions to the problem. Many nations have taken steps to control the increased use of veterinary drugs, but the rules governing their use vary widely from country to country. Sharing of scientific expertise and other resources between countries would markedly improve this situation. With the need for international cooperation mounting, concerned drug regulators from 20 countries met in 1982 and again in 1984 to discuss international use of veterinary drugs. The group repeatedly called for a Codex committee on veterinary drug residues. At its 1983 meeting in Rome the Codex Alimentarius Commission convened an Expert Consultation to consider the need for a new committee. That international group of experts strongly agreed that a standing committee under the sponsorship of the commission should be established. In July of 1985, the commission unanimously voted to establish a new Committee on Residues of Veterinary Drugs in Food. The United States was chosen as host country. The committee will work closely with several existing Codex committees, but it has a clear mandate of its own. Its responsibilities will include establishing a list of priority drugs for review, recommending maximum residue levels, developing codes of practice, and reviewing analytical methods used to control veterinary drug residues. This fall, a new Codex committee has met for the first time--the Codex Committee on Residues of Veterinary Drugs in Food.(ABSTRACT TRUNCATED AT 250 WORDS)

[Onset of puberty in young gilts kept under conditions of intensive husbandry]. / Untersuchungen zum Pubertätseintritt bei Jungsauen unter industriemäbigen Produktionsbedingungen

Gilts that had already reached sexual maturity at the time of insemination showed a higher rate of oestrus and better litter size than immature animals. Therefore animals selected for breeding should have had at least one oestrous cycle. Onset of puberty can be judged by the occurence of a first oestrous with pronounced redness and swelling of the vulva, but without willingness to be mounted. Changing the housing or exercising the gilts, rendered necessary by the production process, had a stimulating effect on the onset of puberal oestrus. Age at onset of sexual maturity did not affect the performance of gilts in their first production cycle, but litter size was greater when the rate of weigth gain was high.