Schwangerschaft bei rheumatoider Arthritis oder Spondyloarthritiden

The activity of a rheumatic disease can be influenced by pregnancy and puerperium. Prospective studies have shown an improvement in joint involvement in rheumatoid arthritis in two thirds to three quarters of pregnancies. After birth, an exacerbation is common. In spondylarthropathies there is no relevant change in disease activity. The fetal outcome is not impaired in patients with rheumatoid arthritis and inflammatory spondylarthropathies. Every pregnancy in women with a rheumatic disease should be considered as high-risk, and such pregnancies require close collaboration between rheumatologists and obstetricians.     

Adenosine instead of supranormal potassium in cardioplegic solution improves cardioprotection.

OBJECTIVE: To determine whether adenosine instead of supranormal potassium in cold crystalloid cardioplegia gives satisfactory cardiac arrest and improved cardioprotection. Cold crystalloid cardioplegia with adenosine, procaine and magnesium (A) was compared with standard cold crystalloid hyperkalemic cardioplegia (K). METHODS: Sixteen pigs were randomized to receive either cold K (n=8) or A (n=8), where hyperkalemia was substituted with 1.2 mM adenosine. The cold (6 degrees C) cardioplegia was given intermittently and antegradely, with an aortic cross-clamp time of 1 h. Hemodynamic data was continuously measured and pressure-volume conductance catheters were used to determine global left ventricular systolic and diastolic function. Coronary flow and O2 content differences allowed determination of left ventricular energetics. Blood samples, and left ventricular microdialysis were used to measure parameters of ischemia. Measurements were done at 1 and 2 h after cross-clamp release. RESULTS: Mean arterial pressure was reduced with 55 mmHg (standard deviation, SD: 19) in the K group versus 30 mmHg (SD: 14) in the A group 2 h after cross-clamp release (p=0.030). Left ventricular contractility expressed as slope of the preload recruitable stroke work index (Mw) was reduced to 53% (SD: 14) in the K group versus 78% (SD: 23) in the A group 2h after cross-clamp release (p=0.046). Reduction of maximum of first derivate of pressure with respect to time (dP/dtmax) was 804 mmHg/s (SD: 189) in the K group versus 538 mmHg/s (SD: 184) in the A group (p=0.033). The slope of the myocardial oxygen consumption-pressure volume area was at 2 h reperfusion increased from 1.37 (SD: 0.64) to 2.86 (SD: 1.27) in the K group, whereas no shift was detected in the A group (p=0.019). Cardiac troponin T measured in the coronary sinus 1 h after cross-clamp release was 1.25 microg/l (SD: 0.64) in the K group versus 0.73 microg/l (SD: 0.31) in the A group (p=0.046). CONCLUSION: Adenosine instead of supranormal potassium in cold crystalloid cardioplegia gives satisfactory cardiac arrest, improves post cardioplegic left ventricular systolic function and efficiency, and attenuates myocardial cell damage.     

Elimination of mycoplasmas from mouse myeloma cells by intraperitoneal passage in mice and by antibiotic treatment

Intraperitoneal passage in mice and antibiotic treatment were evaluated alone and in combination for elimination of mycoplasma contamination of mouse myeloma cell cultures. Intentional infections were established by inoculating Mycoplasma arginini, M. fermentans, M. hyorhinis and M. orale into cell cultures. Successful elimination of mycoplasmas was achieved with all strains tested by intraperitoneal passage in mice, however, cells infected with M. hyorhinis did not survive the infection long enough to be tested. Clindamycin and lincomycin cured cells infected with M. arginini, M. hyorhinis, M. orale but not M. fermentans. M. fermentans were resistant to all antibiotics tested, but could be partially suppressed by clindamycin long enough to permit curing by in vivo passage. M. arginini was eliminated by all antibiotics tested. In vivo passage and treatment with antibiotics is an efficient combination of methods for mycoplasma elimination from cell cultures and has the advantage of being simple and inexpensive.     

Levocabastine compared with sodium cromoglygate eyedrops in children with both birch and grass pollen allergy

Fifty–five children 6–16 years old with allergic rhinoconjunctivitis due to both birch and grass pollinosis were randomized into 2 parallel groups, treated in double–blind fashion with either levocabastinc (LEV) eye–drops twice daily plus placebo eyedrops twice daily or sodium cromoglycate (SCG) eyedrops 4 times daily for 3 months. Spersallerg® (antazolini chloride + tetryzolini chloride) eyedrops were allowed as rescue medicine. All children received basic treatment with an antihistamine (terfenadine) during the complete trial period, and a local nasal corticosteroid if needed. Eye symptoms were recorded daily by the patients and at 4 visits by the investigator, at start and after 4, 10 and 13 weeks. Pollen counts were performed and a blood sample was collected at start and end of the treatment. The global evaluation of treatment was similar for the 2 groups, and there was no significant difference in any effect parameter except for the symptom, itchy eyes, which had lower score in the SCG group as evaluated by the investigator after 4 weeks. On days with low pollen counts the patients in the SCG group had fewer days with moderate or severe eye symptoms. It is concluded that even though LEV and SCG eyedrops were given in addition to systemic treatment with an antihistamine, no consistently significant differences in clinical effect were found between the 2 treatment groups, but the SCG group experienced slightly less eye symptoms throughout the trial. LEV eye–drops appear safe in long–term treatment in children, and no signs of tachyphylaxis were recorded.     

Platelet microvesicles adhere to subendothelium and promote adhesion of platelets.

A role in hemostasis has been suggested for platelet membrane microvesicles (mv). The objectives of the studies reported here include functional analysis of platelet mv in models developed for study of platelet adhesion, as well as investigation of possible interactions between mv and intact platelets in these same adhesion models. Microvesicles were prepared from washed platelet concentrates by repeated freezing and thawing. Adhesion to subendothelium was measured quantitatively by radiolabelling mv with 111-In, and morphologically by scanning electron microscopy. Platelet mv adhered to subendothelium quantitatively over time. Using a modified Baumgartner chamber, we found adhesion of mv to subendothelium significantly increased with increasing shear rates. With this same model we found that prior exposure of subendothelium to mv greatly increased subsequent adhesion of platelets to the same everted vessel, compared to platelet adhesion in the absence of mv. All of these experiments were conducted with mv suspended in ACD/saline, indicating that plasma components are not essential for adhesion of mv. Our studies show that platelet mv adhere to subendothelium in much the same way as do platelets, and support the concept of a hemostatic role for mv in that they appear to increase platelet adhesion.     

A multi-laboratory evaluation of in vitro platelet assays: the tests for extent of shape change and response to hypotonic shock. Biomedical Excellence for Safer Transfusion Working Party of the International Society of Blood Transfusion

BACKGROUND: There is no consensus regarding the use of specific in vitro tests for the assessment of the quality of platelet components. A literature review found that the platelet discoid shape as measured photometrically by the extent of shape change (ESC) and hypotonic shock response (HSR) correlated well with in vivo viability. The purpose of this study was to determine whether multiple research laboratories can perform the ESC and HSR assays in an accurate, reproducible manner, with acceptable sensitivity and comparable results. STUDY DESIGN AND METHODS: Eleven laboratories conducted five identical experiments, each with a different unit of platelet-rich plasma (PRP). For each experiment, 2 half-units of PRP were prepared and stored overnight: 1 half-unit at 20 to 24 degrees C in CPD (CPD-PRP) and the other at 1 to 6 degrees C with 2 mg per mL of EDTA (cold EDTA-PRP) added to produce spherical platelets with reduced HSR. Platelet suspensions having different proportions of the two PRPs were prepared and evaluated in duplicate by ESC and HSR assays, and morphologically scored by microscopy. One-way ANOVA and Duncan multiple-range tests were performed to determine significant differences in assay results for suspensions having different proportions of CPD-PRP. RESULTS: Comparable ESC (mean range: 20–28% for CPD-PRP and 1–6% for cold EDTA- PRP) and HSR (mean range: 58–81% for CPD-PRP and 12–31% for cold EDTA- PRP) measurements were obtained by nine laboratories. Duplicate testing showed high reproducibility of ESR and HSR results /in all laboratories. A 25-percent difference in the proportion of CPD-PRP (indicative of a difference of approximately 25% in the proportions of discoid and spherical platelets) was detected with a sample size of five (p<0.05) for both the ESC and HSR assays. A high correlation was found for the ESC assay and morphology score (r = 0.93, n = 345). CONCLUSION: Multiple laboratories were able to obtain comparable results with the ESC and HSR tests. They were able to show that the tests can be performed in an accurate, reproducible manner and with acceptable sensitivity.     

Paracetamol inhibits replicative DNA synthesis and induces sister chromatid exchange and chromosomal aberrations by inhibition of ribonucleotide reductase

Effects of paracetamol have been studied in a hydroxyurea (HU)-resistant mouse mammary tumour cell line TA3H2, shown to overproduce the small subunit of ribonucleotide reductase. These TA3H2 cells were much more resistant than the TA3H (wild-type) cells towards the inhibitory effect of paracetamol on cell growth, IC50 0.55 mM paracetamol for the wild-type compared to 2.7 mM for the HU-resistant cells. The reduced cell growth was due to an inhibition of replicative DNA synthesis, judged from an increased percentage of cells in S-phase measured by flow cytometry. Furthermore, in the wild-type cells, the increase in the number of cells in S phase was already observed at 0.1 mM while in the HU-resistant cell line this effect was first seen at 3.0 mM paracetamol. HU inhibits ribonucleotide reductase by destroying a tyrosyl free radical located on the small subunit of the enzyme. By electron paramagnetic resonance we demonstrate that paracetamol added to crude cell extracts of HU-resistant cells also immediately destroys this radical. These results show that paracetamol reduces DNA synthesis by a specific inhibition of ribonucleotide reductase. A concentration-dependent induction of sister chromatid exchanges was found both with paracetamol (1.0-10 mM) and HU (0.3-3 mM) in wild-type cells whereas no such increase was observed in HU-resistant cells. Paracetamol (1 mM for 2 h) also increased the number of chromosomal aberrations CAs in wild-type cells (i.e. chromatid breaks and chromatid exchanges). The frequency of CAs was not increased in HU-resistant cells at paracetamol concentrations up to 10 mM.(ABSTRACT TRUNCATED AT 250 WORDS)