Geldanamycin treatment inhibits hemorrhage-induced increases in KLF6 and iNOS expression in unresuscitated mouse organs: role of inducible HSP70.

The aim of this study was to determine whether hemorrhage affects the levels of a variety of stress-related proteins and whether changes can be inhibited by drugs reported to provide protection from ischemia and reperfusion injury. Male Swiss Webster mice were subjected to a 40% hemorrhage without resuscitation. Western blot analysis indicated that c-Jun (an AP-1 protein), Kruppel-like factor 6 (KFL6), and inducible nitric oxide synthase (iNOS) were upregulated sequentially in that order. Pretreatment of mice with geldanamycin (GA) 16 h before hemorrhage effectively inhibited the expression of the proteins KLF6 and iNOS, whereas caffeic acid phenethyl ester did not. GA pretreatment increased inducible heat shock protein (HSP) 70 but not HSP90 in both sham and hemorrhagic tissues. The overexpressed inducible HSP70 formed complexes with KLF6 and iNOS. These results suggest that GA may be therapeutically useful for reducing hemorrhage-induced injury when used as a presurgical treatment or when added to resuscitation fluids.     

Flosequinan in heart failure: acute haemodynamic and longer term symptomatic effects.

There is no single, simple test with which to evaluate new treatments for heart failure. Various methods need to be used, and a study of both the acute haemodynamic and longer term symptomatic effects of flosequinan, a new direct acting arteriolar and venous vasodilator, was therefore carried out in patients with heart failure. In one group of patients flosequinan increased cardiac output and caused a fall in pulmonary capillary wedge pressure, both effects lasting for 24 hours. In a double blind, placebo controlled study in another group flosequinan improved mean exercise tolerance from 9.9 to 12.7 minutes after four weeks of treatment. The drug also reduced perceived exertion during submaximal exercise and increased calf and therefore skeletal muscle blood flow. It reduced plasma renin activity and noradrenaline concentrations. Flosequinan possesses all the important properties of a drug likely to be of value in the treatment of heart failure.     

Extracellular release of photosynthetic products by freshwater phytoplankton populations, with special reference to the algal species involved

SUMMARY. Over three successive years, depth profiles of C-fixation and excretion, chlorophyll- a concentrations, phytoplankton species composition and bacterial numbers were determined in Lake Vechten, a slightly eutrophic lake in The Netherlands. Special attention was given to the method used to measure extracellular release.
Excretion of dissolved organic ¹⁴C depended largely upon the photo-synthetic activity of the phytoplankton, ranging from 0–2.5 mg m^-1 h^-1, representing a percentage extracellular release (PER) of 0–25%.
During a period in August, however, a subsurface chlorophyll- a maximum at 5–7 m depth coincided with high excretion rates of up to 10 mg Cm^-3 h^-1 (PER = 55%). Phytoplankton analysis revealed a stratification in numbers of Mallomonas caudata with a maximum at 5–7 m depth.
The results suggest that in these water layers bacterial populations grew at the expense of the dissolved organic carbon compounds excreted by Mallomonas caudata. This means that extracellular release can temporarily function as an important nutrient source for the heterotrophie community in addition to the more or less constant dissolved organic carbon pool.     

Studies on Fusarium-Gladiolus Interactions

Using standardized conditions, 65 genotypes of Gladiolus were screened for Fusarium resistance. High levels were found in 'large-flowered" types, Primulinus hybrids, G. callianthus, G. garnierii , and G. dalenii. Some accessions of G. dalenii exhibited no disease symptoms when inoculated with two standard test isolates. No resistance was found in 'small-flowered' types. To estimate race-specifity of the resistance, eight highly resistant Gladiolus genotypes were tested in an in vitro test against 43 isolates of F. oxysporum f.sp. gladioli. Two isolates were able to partially infect the G. dalenii accessions and this was confirmed using whole plants. Implications for resistance breeding are discussed.     

The extraction and purification of a peptide from rat insulinoma tissue

A peptide was extracted and purified from rat insulinoma tissue which, although similar, was not identical to normal rat C peptides. The purity of the peptide, called rat insulinoma peptide (RIP), was investigated using polyacrylamide gel electrophoresis, isoelectric focusing and high-performance liquid chromatography. It appears to contain two peptides similar to each other but differing in their isoelectric points. The peptides as assessed by fast atom bombardment mass spectrometry have molecular masses in the region of 1982 Da, given a chain length of approx. 22 amino-acid residues. Evidence obtained using an established rat C peptides radioimmunoassay suggests that RIP shares a common C-terminus with rat C peptides. The antiserum produced to RIP was used to develop a radioimmunoassay using a tracer prepared by iodinating purified tyrosylated RIP.     

Immunological evidence for the capability of free-living Rhizobium japonicum to synthesize a portion of a nitrogenase component

Immunodiffusion tests conducted under aerobic conditions demonstrated that cross-reactive material to antiserum prepared against the MoFe protein component of nitrogenase from soybean nodule bacteroids was detectable in extracts of free-living Rhizobium japonicum cells cultured in a standard medium under: aerobic conditions; aerobic conditions with nitrate; aerobic conditions with ammonia; anaerobic conditions with nitrate; and anaerobic conditions with nitrate and ammonia. The most intense precipitin bands resulted from cross-section of the antiserum with extracts of cells cultured anaerobically with nitrate or anaerobically with ammonia and nitrate. Immunodiffusion experiments with crude bacteroid extract and purified MoFe protein revealed a greater number of precipitin bands in tests conducted under aerobic conditions than those conducted under anaerobic conditions. These results indicate that some of the cross-reactive material observed under aerobic conditions resulted from breakdown of the MoFe protein. Bacteroid extracts of nodules from plants supplied with ammonia exhibited only a trace of nitrogenase activity. The addition of an excess of the Fe protein component of nitrogenase, however, resulted in a 270-fold enhancement of activity indicating the presence of active MoFe protein in these extracts.Our experiments together with results published elsewhere provide evidence that the genetic information for synthesis of a part of the MoFe component of nitrogenase is carried by Rhizobium.     

Comparison of Mobilization after Two and Nine Days in Uncomplicated Myocardial Infarction

A total of 189 patients with uncomplicated myocardial infarction were selected at random for early or late mobilization and discharge from hospital. Patients were admitted to the study after 48 hours in a coronary care unit if they were free of pain and showed no evidence of heart failure or significant dysrhythmia. Randomization was achieved by monthly cross-over of the three medical wards to which the patients were discharged. One group of patients was mobilized immediately and discharged home after a total of nine days in hospital, and the second group was mobilized on the ninth day and discharged on the 16th day. Out-patient assessment was carried out six weeks after admission. No significant differences were observed between the groups in terms of mortality or morbidity, as reflected by the incidence of recurrent chest pain or myocardial infarction, heart failure, dysrhythmia, or venous thromboembolism detected either clinically or by ¹²⁵I-labelled fibrinogen scanning.