Author Correction: Micronuclei in germ cells of hybrid frogs from Pelophylax esculentus complex contain gradually eliminated chromosomes.

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Micronuclei in germ cells of hybrid frogs from Pelophylax esculentus complex contain gradually eliminated chromosomes.

In most organisms, cells typically maintain genome integrity, as radical genome reorganization leads to dramatic consequences. However, certain organisms, ranging from unicellular ciliates to vertebrates, are able to selectively eliminate specific parts of their genome during certain stages of development. Moreover, partial or complete elimination of one of the parental genomes occurs in interspecies hybrids reproducing asexually. Although several examples of this phenomenon are known, the molecular and cellular processes involved in selective elimination of genetic material remain largely undescribed for the majority of such organisms. Here, we elucidate the process of selective genome elimination in water frog hybrids from the Pelophylax esculentus complex reproducing through hybridogenesis. Specifically, in the gonads of diploid and triploid hybrids, but not those of the parental species, we revealed micronuclei in the cytoplasm of germ cells. In each micronucleus, only one centromere was detected with antibodies against kinetochore proteins, suggesting that each micronucleus comprises a single chromosome. Using 3D-FISH with species-specific centromeric probe, we determined the role of micronuclei in selective genome elimination. We found that in triploid LLR hybrids, micronuclei preferentially contain P. ridibundus chromosomes, while in diploid hybrids, micronuclei preferentially contain P. lessonae chromosomes. The number of centromere signals in the nuclei suggested that germ cells were aneuploid until they eliminate the whole chromosomal set of one of the parental species. Furthermore, in diploid hybrids, misaligned P. lessonae chromosomes were observed during the metaphase stage of germ cells division, suggesting their possible elimination due to the inability to attach to the spindle and segregate properly. Additionally, we described gonocytes with an increased number of P. ridibundus centromeres, indicating duplication of the genetic material. We conclude that selective genome elimination from germ cells of diploid and triploid hybrids occurs via the gradual elimination of individual chromosomes of one of the parental genomes, which are enclosed within micronuclei.

[Rehabilitation, social medical evaluation and counselling in HIV-infected patients]. / Rehabilitation, sozialmedizinische Beurteilung und Beratung bei HIV-infizierten Patienten.

An inpatient rehabilitation programme for HIV-infected patients is described. Since the early nineties some 1,200 patients with HIV infection have been treated in our internal and orthopaedic rehabilitation clinic. Beside internal and orthopaedic diagnostics, supporting compliance with antiretroviral therapy, motivating the patients for regular moderate exercises and specific nutritional counselling are major issues of the programme. From the psychological point of view, the patients are offered to aquire relaxation and stress coping techniques, to take part in non-smoking courses and to use individual psychological counselling in case of depression or panic. In addition, all HIV-infected patients are offered individual advice on their disease and necessary changes in lifestyle. Finally, the programme includes social medical evaluation and counselling. As the majority of the patients are still working or are of working age, evaluating the capacity for work and potential introduction of occupational rehabilitation measures are prominent. Almost 70 percent of the HIV-infected patients who had been treated in our clinic over the last few years were fully capable of returning to their previous occupation. Our experiences demonstrate that statements such as rehabilitation of AIDS patients being useless because of its missing prospects of success, are not up-to-date any longer. Since introduction of combination antiretroviral therapy many patients with HIV infection are able to return to their previous occupation if they receive the necessary medical und psychosocial support.

Return to work after myocardial infarction/coronary artery bypass grafting: patients' and physicians' initial viewpoints and outcome 12 months later.

Nonmedical factors play an important role in determining whether patients resume their work after myocardial infarction or CABG. The main questions dealt with in this study are: What is the respective basis of physicians' and patients' judgements as far as vocational disabilities are concerned, and what are the decisive factors that facilitate a prediction as to who will return to work and who will not? 132 male patients participating in a cardiac rehabilitation program served as subjects. The age group was limited to patients between 40 and 59 yr of age. The work situation 12 months following rehabilitation is known for 119 subjects; 74 had resumed their occupations. Results of regression analyses show that patients' and physicians' views on disabilities and re-employment are based on different factors. The physicians derive their estimates mainly from medical variables (cardiac status and comorbidity), whereas the patients' views are based on the overall health status, their former job status, job satisfaction, and negative incentives for the return to work. Three variables were found that allow a prediction to be made as to re-employment in 85% of all cases: (1) age, (2) patients' feelings about the extent to which they are disabled by their cardiac problem, and (3) the physicians' views on the extent to which the patient is vocationally disabled by his overall medical situation. Medical variables (e.g. cardiac status) had little relevance to re-employment. The results are discussed with regard to the consequences for cardiac rehabilitation.

[Nutrient intake with low-fat diets in rehabilitation of patients with coronary heart disease]. / Nährstoffaufnahme bei fettarmen Diäten in der Rehabilitation von Patienten mit koronarer Herzerkrankung.

We investigated the nutritional value of a very low fat diet (diet I) adapted to nutritional habits in Germany. Data were compared to a low fat diet (diet II) according to the American Heart Association. The study was performed in 37 patients with coronary heart disease (30 males and 7 females, age 45-83 yrs) stratified to the 2 dietary treatments. Daily fat intake was 38 g (24% of energy intake of 6.5 MJ/d) in diet I and 60 g (31% of 7.3 MJ/d) in diet II (p < 0.01), respectively. When compared with diet II, in diet I the intake of cholesterol, saturated and mono-unsaturated fatty acids, Vit. A, Vit. D and Vit. B12 were all reduced (p < 0.01), whereas the uptake of Vit. C was increased p < 0.01. The intake of folic acid was low in both groups. Both diets resulted in a decrease in BMI, systolic and diastolic blood pressure, plasma cholesterol and LDL cholesterol levels. Concomitantly plasma triglycerides only decreased in response to diet I but HDL cholesterol levels remained unchanged. Reduction of BMI and cholesterol levels were dependent on baseline BMI and cholesterol concentrations, respectively. The cholesterol lowering effect of diet I is in part attributed to the weight lowering effect of the diet. Taking into account the nutritional habits in Germany, very low fat diets seem to be adequate with respect to their nutritional value. Both diets are effective in lowering body weight, plasma cholesterol and triglyceride levels without affecting HDL cholesterol. These effects are most pronounced in overweight and hypercholesterolemic patients.

Effect of physical activity on serum concentrations of digoxin and digitoxin.

OBJECTIVE: To study the influence of moderate physical activity on serum concentrations of digoxin, digitoxin and albumin. METHODS: Blood samples were drawn from 10 consecutive mobile patients on digoxin and 12 patients on digitoxin therapy before and following a 10-min walking period. Digitalis serum concentrations were determined by radioimmunoassay, and albumin serum concentrations by laser nephelometry. RESULTS: Following physical activity, digoxin serum concentrations dropped immediately to 79% of baseline values and remained significantly decreased for 20 min. Digitoxin concentrations did not change significantly. CONCLUSION: In contrast to digoxin, the effect of physical activity the serum concentration of digitoxin can be disregarded.

[Disorders of color perception in subtoxic and toxic digoxin and serum digoxin concentrations]. / Farbsinnstörungen bei subtoxischen und toxischen Digoxin- und Digitoxinserumkonzentrationen.

Using the Farnsworth-Munsell 100-hue test, investigations were carried out in 14 patients with subtoxic to toxic serum concentrations of digoxin (greater than 2.0 ng/ml) and 13 patients with subtoxic to toxic serum concentrations of digitoxin (greater than 30 ng/ml), in order to detect color vision deficiencies related to serum levels of digitalis. As compared to the control group (n = 24) the total error scores were significantly increased for both glycosides and all serum level ranges. No evidence was found indicating that digoxin and digitoxin influence color vision differently. The FM 100-hue test indicated definite improvements in the digoxin group within one day of discontinuing the glycosides, while the digitoxin group only started to normalize a week later. The results are discussed, taking the different pharmacokinetics of the two digitalis glycosides into account.

[Recurring pulmonary artery embolisms and disseminated intravascular coagulation in right atrial myxoma]. / Rezidivierende Lungenarterienembolien und Verbrauchskoagulopathie bei rechtsatrialem Myxom.

A 33 year old woman presented with dyspnea and dizziness. These symptoms had recurred several times during the months preceding. At initial investigation we palpated a tumor in the upper abdomen corresponding to the sonographic finding of a 10 X 10 cm sized cystic tumor in the liver. Because of reduction of fibrinogen, prolonged thrombin time and thrombocytopenia a malignant disease involving the liver and producing pulmonary embolism and disseminated intravascular coagulation was suspected. However, during routine echocardiography a right atrial mass prolapsing in the right ventricle was detected. After normalization of fibrinogen and thrombin-time following a low dose heparin therapy a myxoma sized 6 X 5 cm was removed from the right atrium. The patient did not recover and died 20 days following surgery. At autopsy the liver tumor proved to be a benign cholangioendothelial cyst.

[Color perception disorders in therapeutic glycoside serum concentrations]. / Farbsinnstörungen bei "therapeutischen" Glykosid-Serumkonzentrationen.

Vision deficiencies are dominant symptoms from digitalis intoxication. Twenty-nine and twenty-eight patients have been examined by the Farnsworth-Munsell-100-Hue-test under common maintenance therapy with digitoxin respectively digoxin or beta-acetyldigoxin. This was done to prove how glycosides may create colour vision disturbances even in "therapeutic" glycoside serum concentrations, and in which degree the lipophile digitoxin differs in its effect from the less lipophile digoxin. To exclude any congenital colour vision deficiencies the study was restricted to females. No definite difference in the total error score has been found among patients treated with digitoxin and digoxin. Our results and further new investigations have pointed out that colour vision in digitalized patients is influenced even under common maintenance therapy. It can also be stated that digitoxin does not influence colour vision other than digoxin.

[Digitoxin in hepatorenal insufficiency]. / Digitoxin bei hepatorenaler Insuffizienz.

Serum digitoxin levels were measured during maintenance treatment with digitoxin, 0.1 mg daily i.v., in 12 patients under intensive postoperative care who had hepatorenal failure resulting from multiple organ failure. Thirteen patients in intensive care with comparable basic diseases served as controls; they had developed predominantly renal failure. Serum digitoxin levels in the two groups were no different and remained within therapeutic range during the total period of observation of 8-40 days. During this time toxic serum digitoxin levels were measured in 2.9% of patients in renal failure and 2.7% of patients with hepatorenal failure. The pathogenesis of the liver failure and the severity of the underlying disease did not influence serum digitoxin levels. Digitoxin was tolerated similarly in the two patient groups.

[Serum level of digoxin and digitoxin and glomerular filtration rate in hyper- and hypothyroidism]. / Serumspiegel von Digoxin und Digitoxin und glomeruläre Filtrationsrate bei Hyper- und Hypothyreose.

In a comparative prospective study the serum levels of digoxin and digitoxin and the glomerular filtration of the kidneys were determined radioimmunologically in thyroid function disorders using the endogenous creatinine clearance and the 51Cr-EDTA clearance. Compared to a euthyroid control group 17 patients with hyperthyroidism showed a decreased and 5 patients with hypothyroidism showed a largely toxic digoxin level, both groups being on a maintenance therapy of 0.25 mg digoxin b. i. d. During an oral maintenance therapy of daily 0.1 mg digitoxin unchanged therapeutic serum levels were found in 35 hyperthyroid and 18 hypothyroid patients when compared to a euthyroid control group. Assessment of clearances showed that glomerular filtration rates were clearly increased in the hyperthyroid and lowered in the hypothyroid patients. Renewed assessment of the clearance in four hyperthyroid patients and three with hypothyroidism after thyroid recompensation showed a marked decrease of clearance values in hyperthyroidism and an increase in hypothyroidism. Increased clearance values in hyperthyroidism were associated with lowered digoxin serum levels. In contrast, lowered clearance values in hypothyroidism were accompanied by increased serum digoxin levels. There was no such association detectable for digitoxin.