Activity of yeast multidrug resistance pumps during growth is controlled by carbon source and the composition of growth-depleted medium: DiS-C3(3) fluorescence assay.

Like other tested wild-type strains (DTXII and IL-125-2B), exponential glucose- and/or fructose-grown cells of Saccharomyces cerevisiae BY4742 exhibit the previously described high activity of Pdr5p and Snq2p pumps (measured as export of the potentiometric fluorescent probe diS-C3(3)). Upon saccharide depletion from the medium the pump activity in these cells, which differ from other strains in having a lower membrane potential, sharply drops to a very low level similar to that found in cells grown on ethanol or glycerol. This negligible pump activity in respiring cells thus appears to have a universal character. Addition of glucose or fructose to respiring BY4742 cells grown to low culture densities restores multidrug resistance pump activity due partly to pump synthesis in pre-existing cells and partly to the high pump activity of newly grown cells; no such pump activity boost occurs when the sugar is added to high-density cultures of ethanol-grown or post-diauxic glucose-grown cells, even if these cultures are diluted to low density by their original growth-depleted medium. A strong sugar-induced increase in pump activity is found solely if respiring cells from high-density cultures are resuspended in fresh YPD or YPE medium before sugar addition. Its absence in respiring cells suspended in growth-depleted medium reflects an as yet unidentified effect of the composition of the growth-exhausted medium (depletion of some components and/or accumulation of extracellular metabolites during yeast growth) on sugar-induced pump activity rise.

Specific sequence of motifs of mitochondrial uncoupling proteins.

We have searched for the exclusivity of common sequence motifs of the mitochondrial uncoupling proteins (UCP1, UCP2, UCP3, UCP4, BMCP1, and plant UCP [PUMP]) within the gene family of mitochondrial anion carrier proteins. The UCP-specific sequences, "UCP signatures", were found in the first, second, and fourth alpha-helices. First: Ala/Ser-Cys/Thr/n-n/Phe-Ala/Gly-[negatively charged residue]-n/Phe-n/Cys-Thr-Phe/n; second: Gly/Ala-Ile/Leu-Gln/X-[positively charged residue]-NH-n/Cys-Ser/nphi/X-n/Ser-OH/Gly-n-[positively charged residue]-Ile/Met-Gly/Val-n/Thr; fourth: Pro-Asn/ Thr-n-X-[positively charged residue]-Asn/Ser/Ala-n-n-Ile/Leu-n-Asn/Val-Cys/n-n/Thr-[negatively charged residue]-n-n/Thr/Pro-OH/Val (n, nonpolar; phi, aromatic; (positively charged residue/negatively charged residue, charged residue). The second and part of the third signature are also present in the yeast dicarboxylate transporter. The UCP signature excluding BMCP1 was also found in the second matrix segment: [positively charged residue]-(Pro/ del-Leu/del)-[positively charged residue]-phi-X-Gly/Ser-Thr/n-X-NH/[negatively charged residue]-Ala-phi. These UCP signatures are thought to be involved in fatty acid anion binding and translocation.

Micropreparation of hemopoietic stem cells from the mouse bone marrow suspension by gravitational field-flow fractionation.

Gravitational field-flow fractionation is a relatively simple experimental technique. This method was used for the characterization of stem cells from mouse bone marrow. Because these cells are bigger than the other cells in bone marrow, it is possible to separate them from the mixture. The fractions collected after passing through the separation channel were characterized using a Coulter Counter and used for transplantation into irradiated mice.

Investigation of red blood cell fractionation by gravitational field-flow fractionation.

Gravitational field-flow fractionation is used for the separation of particles according to their sizes in the range 1-100 microns: larger particles elute before smaller ones. This phenomenon can be explained as a result of the steric exclusion of the particles from the vicinity of the channel walls, and/or hydrodynamic effects supposedly associated with the inertia of the liquid. The method was used for the investigation of red blood cells. The dependence of the retention ratio on the flow-rate, sample volume, concentration of blood and relaxation time was studied. Analysis of fifteen individual fractions by Coulter counter and reinjection of three other fractions were studied in order to verify fractionation of red blood cells.

[Determination of growth scales and ponderal indices in neonates]. / Stanovenie rastových tabuliek a ponderálnych indexov novorodencov.

By retrospective processing of data from 10,002 neonates the authors prepared tables of birth weights and heights incl. percentiles for the 28th-43rd week of gestation. By processing data concerning 9,893 neonates the authors elaborated ponderal indexes for the 32nd-43rd week of gestation. The tables make it possible to evaluate the nutritional status and proportionality of neonates.

[Detection of intrauterine fetal growth retardation using ultrasound fetometry]. / Detekcia intrauterinnej rastovej retardácie plodu pomocou ultrazvukovej fetometrie.

Based on ultrasonic foetometry at an interval of 0-59 days before delivery the authors assessed in 93 women with risk pregnancies hospitalized during the 31st-43rd week of gestation the index of the femur length/abdominal circumference independent on gestation age, and they estimated the foetal weight by means of three logarithmic formulae comprising the biparietal diameter, femur/length and abdominal circumference. For detection of foetal hypotrophy, the estimated weight of the foetus in particular according to the formula of Hadlock et al. (sensitivity 58.3%, specificity 94.22%) was significantly more accurate than the index of femur length/abdominal circumference > or = 23.0 (sensitivity 45.8%, specificity 91.3%).

[Prediction of fetal hypoxia using the fetal biophysical profile]. / Predpoved' hypoxie plodu pomocou fetálneho biofyzikálneho profilu.

In a prospective investigation the authors assessed the diagnostic accuracy of the biophysical profile in the detection of fetal hypoxia. They made 126 tests in 104 risk pregnancies during the 33rd-42nd week of gestation. By means of a scoring system they evaluated six biophysical parameters: non-stress test, fetal breathing movements, fetal movements, fetal tone, volume of amniotic fluid and maturity of the placenta. Ninety-six patients were delivered of a baby within seven days after the test and in these patients the course of childbirth and the condition of the fetus was evaluated. In case of a pathological biophysical score the pregnancy was terminated in 83.3% by Caesarean section, whereby the weight of the fetuses was by 48% lower (1693 g) and the height by 8 cm (41.8 cm) smaller than when the biophysical score was normal. In the detection of an adverse outcome of pregnancy, under which they included an Apgar score of 7 or less during the 5th minute, the first capillary pH less than 7.20 and perinatal death, the biophysical profile had a sensitivity of 68.8%, a specificity of 97.5%, a predictive value of the positive test of 84.6% and a predictive value of the negative test of 94%.

Alternative management of carotid kinking. Surgical technique.

The simple surgical method to correct internal carotid artery kinking is presented. The artery is straightened and fixed to the surrounding tissues without arteriotomy and without interrupting the blood flow. The technique is simple and complication-free in kinks of lesser degree.