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PubMed1991

Determinants of alcohol preference in the AA and ANA rat lines selected for differential ethanol intake.

A selective breeding program conducted in this laboratory has resulted in the establishment of the alcohol-preferring AA (Alko Alcohol) and alcohol-avoiding ANA (Alko Nonalcohol) rat lines. These lines have been used as a tool for attempting to identify the behavioral, neurochemical, and biochemical correlates of differential voluntary ethanol consumption. Some of the differences that have been found between the lines involve differential reinforcement: AA rats, but not ANA rats, rapidly acquire an ethanol-reinforced operant response. The AA's greater development of tolerance to the depressant effects of ethanol and their faster ethanol metabolism would also allow them to drink more. Neurochemical studies have suggested differential functioning of brain monoaminergic mechanisms. The activity of tyrosine hydroxylase and dopa decarboxylase, and the brain dopamine concentrations are higher in the AA rats than in the ANA rats, and the maximal number of dopamine D2 receptors is lower in the AA rats. The concentration of noradrenaline is higher in the brain of ANA rats than in that of AA rats, while the 5-hydroxytryptamine levels do not seem to differ greatly. The importance of these differences to the line difference in ethanol intake is not, however, clear, since there appears to be no difference in the sensitivity of monoamine systems of the two lines to ethanol.

Alcohol Drinking↗
PubMed1979

Differentiation of selected Enterobacteriaceae by pyrolysis-gas-liquid chromatography.

Pyrolysis-gas-liquid chromatography was used to differentiate selected species of Enterobacteriaceae. Individual cultures of Salmonella typhi, Hafnia alvei, and Proteus vulgaris, and 12 strains of Yersinia enterocolitica were grown in nutrient broth. After harvest and lyophilization, the bacterial samples were pyrolyzed at 900 degrees C, and their volatile fractions were separated on a 50-m capillary column coated with Carbowax 20M. The resulting pyrolysis elution patterns (pyrograms) of the four species were monitored on an integrating console, which was coupled with the chromatographic detector. The pyrograms were divided into 312 30-s time interval areas, and each interval area was normalized in relation to the area of the entire curve. The normalized areas were evaluated by stepwise linear discriminant analysis, and the discriminating component coordinates were used to generate a plot of the canonical variables. Distinct clustering patterns allowed discrimination among the four genera of Enterobacteriaceae studied. The tight clustering of the 12 Y. enterocolitica strains suggests the advantage of pyrolysis-gas-liquid chromatography over traditional approaches for species identification.

Bacteriological Techniques↗
PubMed1986

Selection in Hereford cattle. I. Selection intensity, generation interval and indexes in retrospect.

Selection intensity and generation interval were evaluated in a Hereford cattle herd made up of 14 inbred lines and 14 linecross groups corresponding to the lines of inbred sires at the Suan Juan Basin Research Center, Hesperus, Colorado. Selection indexes practiced were calculated in retrospect. Analyses of the records collected from 1946 through 1973 involved weaning weight (WW) and postweaning traits in males and females. Analyses by line were performed for the inbreds, while pooled analyses were done on the inbred and linecross populations. From records of 1,239 calves weaned, age of sire averaged 3.75 yr compared with 4.52 yr for age of dam, showing faster generation turnover for sires than for dams. Generation interval determined as actual age of midparent was 4.13 yr. Selection applied for WW, evaluated as annual selection differentials within inbred lines and then pooled over all lines, averaged .55 standard deviations (sigma)/generation for sires. For females, selection was much less intense. Midparent selection differential amounted to .33 sigma/generation. For sires, pooled standardized selection differentials per generation over all lines during the postweaning gain period were .49 sigma, .46 sigma, .40 sigma, -.20 sigma, -.10 sigma and .69 sigma, respectively, for initial weight, final weight, feed consumed, feed efficiency (FE, unadjusted and adjusted) and average daily gain (ADG). Selection of females for postweaning traits was not intense. Selection index actually practiced in retrospect for sires was: IS = .4461 (WW) - .0092 (FE) + .6126 (ADG). The indexes for dams included WW, 12-mo weight (12W), 18-mo weight (18W), mature spring weight (SPW) and mature fall weight (FAW) and were: for inbred dams, ID = .1824 (WW) - .0284 (12W) + .0736 (18W) - .1097 (SPW) - .1097 (FAW); for linecross dams, ID = .2693 (WW) - .2960 (12W) + .0147 (18W) + .1185 (SPW) - .0354 (FAW). The corresponding index selection differentials were .818, .203 and .209. Sire index selection differentials represent about 79% of the total selection differentials.

Animals↗
PubMed2000

Genetics of growth and reproduction in the turkey. 14. Changes in genetic parameters over thirty generations of selection for increased body weight.

A line (F) of turkeys was selected over 30 generations for increased 16-wk BW. The base population for the F line was a randombred control population (RBC2) that was maintained without conscious selection and used to remove yearly environmental variation in the F line. Selection was effective in increasing 16-wk BW in the F line. Selection differentials based on the mean of selected parents minus mean of entire population (intended) and intended selection differentials weighted for number of offspring produced (actual) did not consistently differ, indicating that natural selection was not significantly opposing artificial selection. The realized heritability (h2) of 16-wk BW in the F line, based on the linear regression of the selection response on accumulated actual selection differentials, declined with selection; the decline appeared to be slightly different for males than females. For both sexes combined, the realized h2 was 0.309+/-0.022 (SE), 0.268+/-0.033, 0.242+/-0.026, and 0.254+/-0.007, respectively, for Generations 1 to 10, 11 to 20, 21 to 30, and 1 to 30. Genetic increases in 16-wk BW in the F line were positively associated with BW at other ages (8, 20, and 24 wk of age and at 50% production), days from stimulatory lighting to production of the first egg, and egg weight. Genetic increases were negatively associated with egg production, intensity of lay (maximum and average clutch length and rate of lay), and hatch of fertile eggs. There was no significant relationship between 16-wk BW and total days lost from broodiness or fertility. The genetic changes in some correlated traits were not consistent in all generation intervals studied, indicating that the genetic correlation between the selected trait (16 wk BW) and the correlated trait changed with selection.

Animals↗
PubMed2005

Comparison of three models to estimate breeding values for percentage of loin intramuscular fat in Duroc swine.

Three selection models were evaluated to compare selection candidate rankings based on EBV and to evaluate subsequent effects of model-derived EBV on the selection differential and expected genetic response in the population. Data were collected from carcass- and ultrasound-derived estimates of loin i.m. fat percent (IMF) in a population of Duroc swine under selection to increase IMF. The models compared were Model 1, a two-trait animal model used in the selection experiment that included ultrasound IMF from all pigs scanned and carcass IMF from pigs slaughtered to estimate breeding values for both carcass (C1) and ultrasound IMF (U1); Model 2, a single-trait animal model that included ultrasound IMF values on all pigs scanned to estimate breeding values for ultrasound IMF (U2); and Model 3, a multiple-trait animal model including carcass IMF from slaughtered pigs and the first three principal components from a total of 10 image parameters averaged across four longitudinal ultrasound images to estimate breeding values for carcass IMF (C3). Rank correlations between breeding value estimates for U1 and C1, U1 and U2, and C1 and C3 were 0.95, 0.97, and 0.92, respectively. Other rank correlations were 0.86 or less. In the selection experiment, approximately the top 10% of boars and 50% of gilts were selected. Selection differentials for pigs in Generation 3 were greatest when ranking pigs based on C1, followed by U1, U2, and C3. In addition, selection differential and estimated response were evaluated when simulating selection of the top 1, 5, and 10% of sires and 50% of dams. Results of this analysis indicated the greatest selection differential was for selection based on C1. The greatest loss in selection differential was found for selection based on C3 when selecting the top 10 and 1% of boars and 50% of gilts. The loss in estimated response when selecting varying percentages of boars and the top 50% of gilts was greatest when selection was based on C3 (16.0 to 25.8%) and least for selection based on U1 (1.3 to 10.9%). Estimated genetic change from selection based on carcass IMF was greater than selection based on ultrasound IMF. Results show that selection based on a combination of ultrasonically predicted IMF and sib carcass IMF produced the greatest selection differentials and should lead to the greatest genetic change.

Adipose Tissue↗
PubMed1997

Purified unfractionated G-CSF/chemotherapy mobilized CD34+ peripheral blood progenitors and not bone marrow CD34+ progenitors undergo selective erythroid differentiation in liquid culture in the presence of erythropoietin and stem cell factor.

A combination of erythropoietin (EPO) plus stem cell factor (SCF) drove purified unfractionated granulocyte colony stimulating factor (G-CSF)/chemotherapy mobilized peripheral blood CD34+ cells to selective erythroid differentiation in liquid culture with an average 28-fold increase in the total cell number after 21 d. From day 6 of culture cytologic and cytofluorimetric characterization revealed that cultured cells belonged to the erythroid lineage with a gradual wave of maturation along the erythroid pathway to terminal cells. A similar pattern of erythroid differentiation was observed when the same peripheral blood CD34+ cells were culture with EPO plus SCF in serum-free medium. This cytokine combination produced selective erythroid differentiation with the complete exhaustion of the clonogenic potential on day 21. In parallel experiments the same circulating CD34+ cells underwent granulocytic/ monocytic differentiation in liquid culture in response to granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin-3 (IL-3) and SCF, demonstrating that these CD34+ progenitors had intact pluripotent differentiating potential. Conversely, bone marrow CD34+ cells isolated from bone marrow allografts were unable to selectively differentiate along the erythroid pathway when they were exposed to EPO plus SCF combination. However, these cells maintained a greater number of colony forming cells on day 21 of culture compared to mobilized peripheral blood CD34+ cells. This model is a simple and reliable way to obtain selective erythroid differentiation of peripheral blood G-CSF/ chemotherapy mobilized CD34+ progenitor cells in liquid culture. The absence of cytokines such as GM-CSF and IL-3 in the culture medium permits studies on in vitro erythropoiesis without disturbance of prevalent myelopoiesis.

Antigens, CD34↗
PubMed1985

Selection for weaning weight and postweaning gain in Hereford cattle. I. Population structure and selection applied.

Single trait selection was practiced in three lines of Hereford cattle derived from a common base population. Selection was practiced on males only within sire families for increased weaning weight (WW) in the WW line (WWL), for postweaning gain (PG) in the PG line (PGL) and at random in the control line (CTL). Females were culled on the basis of age or reproductive failure. Progeny of selected bulls were produced in two herds from 1970 through 1981. The data consisted of records on 2,467 progeny of 125 sires and 922 dams. Generations of selection to produce the 1981 calf crop were 1.96, 1.85 and 1.80 for WWL, PGL and CTL, respectively. For calves born in 1981, mean cumulative selection differentials (CSD) were 54.5 kg in WWL and 37.8 kg in PGL. Corresponding values in standard deviation units (SDU) were 2.31 and 1.68, respectively. Secondary selection differentials were 25 to 40% as large as selection differentials for the primary traits. Unintentional selection in the CTL in 1981 was 16.2 kg or .68 SDU for WW and .2 kg or .01 SDU for PG, respectively. Regressions of CSD on year were 4.1 kg or .17 SDU in WWL and 3.2 kg or .14 SDU in PGL. Realized selection differentials were approximately 88% of the potential selection differentials in both lines. Inbreeding coefficients of dam and calves in 1981 were 2.0 and 3.5% in WWL, 2.1 and 3.5% in PGL and 2.9 and 5.8% in CTL.

Animals↗
PubMed1993

The close relationship between DNA replication and the selection of differentiation lineages of human erythroleukemia cell lines K562, HEL, and TF1 into either erythroid or megakaryocytic lineages.

The selection of differentiation lineages into either erythroid or megakaryocytic series was analyzed with human erythroleukemia cell lines K562, HEL, and cytokine-dependent TF1. A tumor promoter, TPA, induced a megakaryocyte marker, glycoprotein IIb/IIIa (GP IIb/IIIa) or IIIa (GP IIIa), but suppressed erythroid differentiation. On the other hand, aphidicolin, which is a potent inhibitor of DNA replication, inhibited GP IIb/IIIa or IIIa expression, but induced the expression of erythroid phenotypes. These phenomena were observed in all erythroleukemia cell lines tested. The bromodeoxyuridine labeling experiments indicated that de novo DNA synthesis was completely suppressed by aphidicolin treatment but was well preserved in TPA-treated cells. Among these three cell lines, erythropoietin (EPO) treatment induced erythroid differentiation of TF1 cells, which was dependent on GM-CSF or IL-3. In this case, EPO functioned as the survival factor and mild stimulator for cell proliferation as well as the inducer of erythroid differentiation. However, when either GM-CSF or IL-3 was depleted from the culture medium, TF1 ceased cell growth; concomitantly, hemoglobin-positive cells appeared, which is consistent with the results obtained with aphidicolin. The incubation of K562 cells for 48 h with either TPA or aphidicolin induced the irreversible commitment of cells to megakaryocytic and erythroid lineages, respectively. Our results using three different erythroleukemia cell lines suggest that a possible linkage between the DNA replication system and the selection of a differentiation lineage is the common feature of human erythroleukemia cell lines, and that these culture systems provide a suitable model for the analysis of the signal transduction system for differentiation lineage selection.

Aphidicolin↗
PubMed2002

R8 development in the Drosophila eye: a paradigm for neural selection and differentiation.

The Drosophila eye is an outstanding model with which to decipher mechanisms of neural differentiation. Paramount to normal eye development is the organized selection and differentiation of a patterned array of R8 photoreceptors - the founding photoreceptor of each ommatidium that coordinates the incorporation of all other photoreceptors. R8 development is a complex process that requires the integration of transcription factors and signaling pathways, many of which are highly conserved and perform similar functions in other species. This article discusses the developmental control of the four key elements of R8 development: selection, spacing, differentiation and orchestration of later events. New questions that have surfaced because of recent advances in the field are addressed, and the unique characteristics of R8 development are highlighted through comparisons with neural specification in other Drosophila tissues and with ganglion cell development in the mammalian retina.

Animals↗
PubMedDate not supplied

Thoracoscopic splanchnicectomy for "small duct" chronic pancreatitis: case selection by differential epidural analgesia.

Management of patients with intractable pain from "small duct" chronic pancreatitis has been difficult, often resulting in narcotic addiction and/or malnutrition from major pancreatic resection. Recently, denervation of sympathetic pain afferents from the pancreas by surgical splanchnicectomy has shown promise in relieving pain while preserving residual pancreatic function. However, results from surgical splanchnicectomy have been mixed in large part because of patient selection. Differentiating actual pancreatic pain from "pancreatic" pain caused by drug-seeking behavior, psychogenic diseases, or various somatically innervated conditions is clinically challenging at best. Between 1992 and 1996, twenty-two patients with 20 prior pancreatic operations, "small duct" chronic pancreatitis, and "pancreatic" pain requiring narcotics were evaluated. Each underwent differential epidural analgesia (DEA) using the following standard techniques: placebo, low-dose (sympathetic), and high-dose (somatic) blocks. Pain perceptions were recorded before and after DEA using a visual analogue scale (VAS). Six demonstrated a greater than 50% decrease in VAS pain after placebo injection and were eliminated from further study. In the remaining 16 patients, pain relief only occurred with sympathetic or somatic blockade. Greater and lesser splanchnicectomy (surgical splanchnicectomy) was performed 27 times in these 16 patients (11 bilateral, 6 synchronous) (5 unilateral; 2 right and 3 left) using thoracoscopic techniques in 14 patients and open thoracotomy in two. No significant surgical or anesthetic complications were encountered. Surgical splanchnicectomy resulted in an overall significant reduction in preoperative VAS scores (8.25 to 4.18; P <0.05). Ten of 13 patients with DEA-predicted sympathetic pain experienced a greater than 50% decrease in VAS after surgical splanchnicectomy, but only two had complete relief. None of the three patients with DEA-predicted somatic pain were benefited by splanchnicectomy. During an average follow-up of 23.3 months, initial good results from surgical splanchnicectomy were maintained in 8 of 10 patients. The following conclusions were reached: (1) surgical splanchnicectomy is a safe, often effective technique for amelioration of intractable pain from "small duct" chronic pancreatitis and (2) DEA is a promising approach for identifying patients most likely to respond to surgical splanchnicectomy.

Adult↗
PubMed1995

Sex mortality differentials and selective survival in large medfly cohorts: implications for human sex mortality differentials.

Experimental studies on male-female mortality differences in nonhuman species are important because they provide insights into both the nature of age-specific gender differences and the concept of selective survival--whether one subgroup in a population (e.g., males) is consistently more frail than another subgroup (e.g., females). We found that it was not possible to classify either sex as more robust or longer lived since relative longevity was conditional on age (young or old), cage conditions (solitary confinement or grouped cages), and treatment (starvation, irradiation, or density). Implications of these findings are discussed including selective survival, demographic selection, a framework for male-female mortality differentials, and an evolutionary perspective on gender differences in longevity.

Animals↗
PubMed2002

Dwarfism in insular sloths: biogeography, selection, and evolutionary rate.

The islands of Bocas del Toro, Panama, were sequentially separated from the adjacent mainland by rising sea levels during the past 10,000 years. Three-toed sloths (Bradypus) from five islands are smaller than their mainland counterparts, and the insular populations themselves vary in mean body size. We first examine relationships between body size and physical characteristics of the islands, testing hypotheses regarding optimal body size, evolutionary equilibria, and the presence of dispersal in this system. To do so, we conduct linear regressions of body size onto island area, distance from the mainland, and island age. Second, we retroactively calculate two measures of the evolutionary rate of change in body size (haldanes and darwins) and the standardized linear selection differential, or selection intensity (i). We also test the observed morphological changes against models of evolution by genetic drift. The results indicate that mean body size decreases linearly with island age, explaining up to 97% of the variation among population means. Neither island area nor distance from the mainland is significant in multiple regressions that include island age. Thus, we find no evidence for differential optimal body size among islands, or for dispersal in the system. In contrast, the dependence of body size on island age suggests uniform directional selection for small body size in the insular populations. Although genetic drift cannot be discounted as the cause for this evolution in body size, the probability is small given the consistent direction of evolution (repeated dwarfism). The insular sloths show a sustained rate of evolution similar to those measured in haldanes over tens of generations, appearing to unite micro- and macroevolutionary time scales. Furthermore, the magnitude and rate of this example of rapid differentiation fall within predictions of theoretical models from population genetics. However, the linearity of the relationship between body size and island age is not predicted, suggesting that either more factors are involved than those considered here, or that theoretical advances are necessary to explain constant evolutionary rates over long time spans in new selective environments.

Animals↗
PubMed1982

Effects of pentobarbital in mice selected for differential sensitivity to ethanol.

Two lines of mice have been genetically selected for differential sensitivity to ethanol. These lines have been designated long sleep (LS) and short sleep (SS) on the basis of their hypnotic response to the ethanol selection dose. Earlier studies of these mice suggested that this difference was limited to alcohols and did not extend to other classes of hypnotics. The present study examined hypnotic and hypothermic responses produced by pentobarbital in recent generations of these mice. Dose-dependent differences in sleep time and in hypothermia were found, with SS mice affected to a greater degree than LS mice. Pharmacokinetic studies showed that the half-life of pentobarbital disappearence from SS blood was twice that reported for SS mice of the 18th generation. The half-life in the LS line had not changed. The volumes of distribution and waking brain concentrations were identical in LS and SS mice. An altered rate of elimination (not differential CNS sensitivity) appeared to be the major factor responsible for the differences observed between these lines.

Alcohol Drinking↗
PubMed1989

Selective and differential medium for isolation of Bacteroides ureolyticus from clinical specimens.

A new selective and differential medium for Bacteroides ureolyticus was compared with other commonly used selective media for anaerobes in a diagnostic trial with routine clinical specimens. All Bacteroides ureolyticus strains grew on nalidixic acid-teicoplaninurea agar, producing red colonies against a straw-coloured background. This medium was found to be the most selective for Bacteroides ureolyticus. In the diagnostic trial with 185 clinical specimens a 20% increase in the isolation rate of Bacteroides ureolyticus was obtained with this new medium.

Bacteroides↗
PubMed1982

Differential and selective medium for isolation of Yersinia enterocolitica from stools.

A new differential and selective medium, DYS agar, was developed and evaluated from the isolation of Yersinia enterocolitica. Ther bile salts content of the medium resulted in high selectivity, and inclusion of arabinose, lysine, and arginine rendered Y. Enterocolitica very distinct from Proteus spp., Pseudomonas spp., and other members of the family Enterobacteriaceae. DYS medium was more efficient for the isolation of Y. enterocolitica from experimentally inoculated fecal specimens than MacConkey, deoxycholate-citrate, and salmonella-shigella agars. Although the medium showed selectivity similar to that of another relatively new medium. Y medium (a selective medium for Y. enterocolitica containing sodium oxalate). DYS agar was found to be superior to Y medium in terms of differentiation of Y. enterocolitica from other intestinal organisms. DYS medium is simple to prepare.

Arabinose↗
PubMed2000

Fertility and mortality differentials among selected tribal population groups of north-western and eastern India.

Selection potential based on differential fertility and mortality has been computed for six tribal groups inhabiting different geo-climatic conditions, namely: Sahariya, Mina and Bhil of the State of Rajasthan, north-western India, and Munda, Santal and Lodha of the State of West Bengal, eastern India. Irrespective of the methodology, the total index of selection was found to be highest among Lodhas (0.668), followed by Sahariyas (0.524), Santals (0.462), Bhils (0.386), Mundas (0.353) and Minas (0.334). Incidentally, Lodha and Sahariya are two of the seventy-four notified primitive tribal groups of India, and these two study populations show the highest index of total selection, mainly because of a higher embryonic and postnatal mortality. The relative contribution of the fertility component to the index of total selection is higher than the corresponding mortality component in all tribal groups. The analysis of postnatal mortality components indicates that childhood mortality constitutes the bulk of postnatal mortality, suggesting that children under 5 years need better health care in these tribal groups.

Adult↗
PubMed1981

Selective and differential media for isolation and tentative identification of each species of Pityrosporum residing on normal or diseased human skin.

Selective and differential media were designed for each species of Pityrosporum; P. pachydermatis, P. ovale, and P. orbiculare in order to make feasible a quantitative cultivation. Medium for P. pachydermatis (medium A) was composed of 1% trypticase peptone (BBL), 0.5% yeast extract (BBL), 0.3% glucose, 0.2% NaCl, 1.2% KH2 PO4 (anhydrous), 1.5% agar, 0.01% ampicillin, and 0.025% cycloheximide with a pH of 5.5. Medium for P. ovale (medium B) was medium A supplemented with 0.05% sodium acetate (anhydrous), 0.2% Tween 80, and 0.025% (selective medium) or 0.075% (differential medium) sodium laurate. Medium for P. orbiculare was medium B (devoid of laurate) supplemented with 2% olive oil, 0.25% glycerol, 0.25% gall powder, 0.05% sodium palmitate, 0.05% sodium stearate, 0.05% sodium oleate and 8% (selective medium) or 10% (differential medium) sodium lactate and an increase in Tween to 1%. For isolation of Pityrosporum, specimens were suspended in 0.1% Tween 80 solution and inoculated onto agar plates of three selective media. The plates were incubated aerobically at 37 C for 8-10 days under conditions of prevention of water loss from the media. The plating efficiency of each selective medium, expressed as a ratio of cultural counts to microscopic counts was generally over 70%. Species of Pityrosporum could also be identified when we inoculated the cell suspension onto differential agar plates and incubated the preparations at 37 C for 7 days.

Culture Media↗
PubMed1996

[The level of alcohol and titre of A and B group substances of the ABO system in blood samples infected by some strains of Escherichia coli].

Evaluating the results of sectional blood examinations for ethyl alcohol content is difficult due to the proceeding putrid and fermentative processes, in consequence of which endogenic ethyl alcohol is produced. Some difficulties also arise from estimating the results of serological investigations concerning the biological traces having been changed by putrefaction, where the presence of heterogenic antigens may be suspected. The putrid-fermentative processes are linked with the activity of microorganisms, particularly bacteria and yeast-like fungi. The first part of the paper deals with the bacterial flora in 50 sectional blood samples taken for routine determinations of ethyl alcohol content, thus with added sodium fluoride as bacteriostatic agent. The identification of the microorganisms cultured on differentiating and selectively differentiating media was carried out on the basis of the culture appearance, specimens stained by Gram's method, as well as biochemical examinations. From 16 studied samples of the sectional blood no strain of bacteria was cultured, mixed bacterial flora was isolated from the remaining ones (Tab. 1). Most numerous were Gram-negative bacteria (71%) among which E.coli appeared most frequently. Gram-positive claimed 28% of the cultured microflora, while anaerobes hardly 4%. In the second part of the paper, the selected strains of E. coli pertaining to serological groups: 02, 04, 06, 08, 09, 022, 025 were studied with regard to their possibility to produce ethanol as well as antigens A and B of AB0 system. E.coli strains were grown on broth medium containing glucose in concentration of from 0.00 to 27.75 mmol/l and human blood of 0 group collected from blood-donors on sodium citrate and CPD preservative with glucose in its content. Ethanol concentration in cultures was determined after 24 and 72 hours of incubation, by gas chromatography method, and glucose by enzymatic method. In serological investigations the material consisted of linen pieces being covered with 72-hour cultures of E.coli on broth and human blood of group 0. The study for the presence of the group substances A and B of AB0 system was performed by absorption method according to Holzer, and by absorption and elution method. In consequence of the studies it has been ascertained that sodium fluoride added as a bacteriostatic agent does not entirely inhibit the growth of bacteria, and especially bacteria Gram-negative appeared to be least sensitive to its action (Tab. 1). Selected strains of E.coli have differed with regard to the efficiency of ethanol production (Tab. 2). The level of produced ethanol depended on glucose concentration in the medium, temperature and the incubation time (Tab. 2, 3, 4 and Fig. 1). Under almost similar conditions the same strains produce more alcohol than on blood, which may give rise to supposition that the blood modifies the metabolism of bacteria (Tab. 4 and 5). The cultures of selected strains studied failed to reveal the presence of heteroantigens with properties of antigen A and B of AB0 system.

ABO Blood-Group System↗