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Conjugation between two Pseudomonas putida species has been studied. Special emphasis has been given to the design of tools for better defined and reproducible experimental conditions. This is an essential prerequisite for any kinetic analysis of the phenomenon. The experimental approach suggested in the paper is a three-stage continuous fermentation, where donor and recipient strains can be cultivated at predefined steady-state growth rates, and conjugation takes place at steady-state conditions in the third stage. For the first time a remarkable influence of agitative speed on conjugation has been experimentally observed.

Recurring paroxysmal abdominal pain developed in a 19-year old woman suffering from acute lymphatic T-cell leukaemia, during induction chemotherapy with cyclophosphamide, cytarabine and mercaptopurine. Both the plain radiograph and CT of the abdomen showed pathognomonic intramural gas accumulations and free air below the right diaphragm, pointing to pneumatosis coli. There was marked pancytopenia (leucocytes 800/microliters,haemoglobin 7.6 g/dl, thrombocytes 10,000/microliters). Whereas the abdominal pain subsided rapidly under oxygen therapy and liquid nourishment, the radiological changes receded gradually. However, fever and diarrhoeas occurred subsequently. Fever persisted for 3 weeks despite treatment with antibiotics (three times 60 mg/d gentamicin, three times 2 g/d mefoxitin and three times 500 mg/d metronidazole, and later 30 mg/d amphotericin B) and subsided only after completion of the induction chemotherapy and an increase of leucocyte count.

Following a case report of a newborn with Ivemark's syndrome, we go into etiology, embryology, and anatomy of this congenital cardiovascular disease with asplenia and other visceral abnormalities. The cause of this complex disorder is an exogen or endogen factor active between the 28th and 32nd day of embryological development. Lethality with or without operation is high, therefore clinical diagnosis should possibly be made early by X-ray of chest and abdomen, blood smear, ultrasound, and angiocardiographic investigations.

To investigate the extent of streaming of umbilical venous blood in the venous and arterial circulations of normal and hypoxic sheep fetuses and to experimentally determine its effect on determinations of blood flow by means of the microsphere method, we injected 15 mu microspheres labeled with different radionuclides into the umbilical veins (UVs) and distal inferior venae cavae (DIVC) of 21 chronically catheterized near-term sheep fetuses. We determined the ratio of the radioactive counts from the UV-injected microspheres to the radioactive counts from the DIVC-injected microspheres (UV/DIVC count ratio) in each fetal tissue in 40 experiments. In 75% of the normal fetuses and 58% of the hypoxic fetuses, UV-injected microspheres streamed preferentially through the foramen ovale to the left atrium and ventricle when compared with DIVC-injected microspheres. Fetal hypoxia was associated with a significant decrease in the extent of preferential streaming. In the arterial circulation, we found no evidence for preferential streaming of UV-injected and DIVC-injected microspheres.

Measurements of phasic blood flow in the inferior and superior venae cavae and umbilical vein of fetal sheep (gestational age, 121 to 140 days) were made with chronically implanted electromagnetic flow transducers. In the venae cavae blood flow was inversely related to phasic changes in venous and/or intrathoracic pressure. During fetal apnea a forward surge of flow occurred during ventricular systole (systolic surge) and ventricular diastole (diastolic surge). Slower fetal heart rates were associated with a more prominent diastolic surge. Reductions in afterload caused by acetylcholine administration augmented the peak diastolic venous flow. In contrast, increased afterload caused by hypoxia and norepinephrine administration was associated with increased peak systolic flow. During regular fetal breathing movements the phasic flow pattern was determined largely by the respiratory cycle with the effect of the cardiac cycle superimposed. There was minimal venous pulsation in the intra-abdominal umbilical vein, compared with that of the intrathoracic venae cavae of the apneic fetus. Our findings demonstrate that fetal systemic vascular resistance profoundly influences right atrioventricular filling patterns.

Fetal heart rate (FHR) and oxygen consumption were determined in 45 studies in 20 chronically instrumented, normoxic sheep. FHR variability was measured by a template device to determine amplitude range, and oscillatory frequency was manually counted over 5-min periods. During 26 min of isocapnic hypoxia, fetal O2 consumption decreased 39% and FHR decreased 18%, and FHR variability increased, the changes being maintained over the treatment period. It is suggested that the maintenance of FHR variability during this profound hypoxia denotes adequate cardiorespiratory compensatory mechanisms during the short period; prolongation of the hypoxia would probably result in fetal cerebral or myocardial decompensation, and disappearance of FHR variability. The increased variability may be due to increased alpha-adrenergic activity.

The angiographic picture of metastatic choriocarcinoma is well known since long, computertomographic findings, however, have not yet been described. The article gives a case-report and discusses the computertomographic picture of the disease.

The presence of vascular shunts in the fetal circulation results in mixture of oxygenated blood returning from the placenta with venous blood returning from the fetal body. In fetal sheep with chronically implanted vascular catheters we found during normal oxygenation that 22% of umbilical venous blood recirculated to the placenta without being presented to the fetal tissues (left-to-right shunt analogue) while about half of systemic venous blood recirculated to the fetal body and not to the placenta for oxygenation (right-to-left shunt analogue). These shunts comprised 34% of cardiac output and increase the workload on the fetal heart, as they are ineffective in terms of oxygen uptake and delivery. In normally-oxygenated fetuses, 11% of cardiac output was comprised of umbilical venous blood recirculating to the placenta (left-to-right shunt analogue) whereas 23% of cardiac output consisted of systemic venous blood circulating to the fetal body (right-to-left shunt analogue). During induced maternal-fetal hypoxia (10% O2 to ewe), although the percentage of ineffective cardiac output did not change (31%), the left-to-right shunt analogue increased to 19% and the right-to-left shunt analogues decreased to 12% of cardiac output. Hypoxia also resulted in an increase in the percentage of umbilical venous blood which bypassed the liver through the ductus venosus (control 57 +/- 12%; hypoxia 65 +/- 12%, P < 0.02), causing the proportion of umbilical venous blood contributing to the fetal cardiac output to increase from 27 +/- 10% during normoxia to 39 +/- 9% during hypoxia (P < 0.005). This factor, together with the redistribution of cardiac output during hypoxia, resulted in a 100% increase in oxygen delivery from umbilical venous blood to the myocardium and a maintenance of the umbilical vein derived oxygen supplied to the brain and placenta, despite a 40% reduction in total available oxygen in umbilical venous blood.