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Capnophorin (Band 3) is the major red cell transport protein, present in human erythrocyte membranes at 1 × 106 copies per cell. Under physiological conditions, the transporter is capable of moving 50 mol (Cl−/HCO3−) 1 cells−1 min−1 (Knauf, 1979), this high rate being necessary for carriage of CO2 in normal respiration (Wieth et al. 1982). In the present paper we demonstrate that, in contrast to the situation in all other vertebrate species studied except the lamprey (Ohnishi & Asai, 1985), capnophorin activity in hagfish red cells is very limited, amounting to only 40 μmol Cl− transported 1 cells-1 min-1 at 11 °C, the environmental temperature of this species. Five experimental approaches were used to characterize this transporter in hagfish red cells: pH regulation in lightly buffered medium; 36C1− uptake; 36C1− efflux; effects of H2DIDS (dihydro-4,4-diisothiocyanostilbene 2,2-disulphonic acid), a specific capnophorin inhibitor (Knauf, 1979); and sodium dodecyl sulphate (SDS) polyacrylamide gel electrophoresis (PAGE).

Binding of the potent nucleoside transport inhibitor [3H]nitrobenzylthioinosine to rat and guinea pig lung membranes was investigated. Reversible high-affinity binding was found in both species (apparent K D ∼ 0.3nM). Binding was inhibited by nitrobenzylthioguanosine, adenosine and uridine. Dipyridamole was also an effective inhibitor of [3H]nitrobenzylthioinosine binding to guinea pig membranes. In contrast, rat membranes were relatively insensitive to dipyridamole. Exposure of site-bound [3H]nitrobenzylthioinosine to high intensity U.V. light resulted in the photoaffinity labelling of lung proteins with apparent molecular weights similar to that of the human erythrocyte nucleoside transporter (45,000–65,000).

The amino acid permeability of red blood cells from Equus caballus (thoroughbred, Arab, shire and pony), E przewalskii (Przewalski’s horse), E asinus (donkey and mule) and E burchelli (common or plains zebra) was measured. Individual animals exhibited stable but widely differing rates of L-[U-14C]alanine uptake in the range 5 to 1554 μmol (litre cells)h-1 (0-2 mM extracellular L-alanine, 37°C). Of the thoroughbreds tested, 30 per cent had red blood cells which were essentially impermeable to L-alanine (5 to 10 μmol (litre cells)-1 h-1, giving transport rates similar to those found previously in amino acid transport-deficient sheep erythrocytes. In contrast, only 3 per cent of the ponies tested had red blood cells impermeable to L-alanine. No cases of erythrocyte amino acid transport deficiency were found in the other horse breeds and species tested.

Na+-dependent system ASC and Na+-independent system asc are characterized by a common selectivity for neutral amino acids of intermediate size such as L-alanine and by their interactions with dibasic amino acids. For system ASC, the positive charge on the dibasic amino acid side chain is considered to occupy the Na+-binding site on the transporter. We report here the use of harmaline (a Na+-site inhibitor in some systems) as a probe of possible structural homology between these two classes of amino acid transporter. Harmaline was found to inhibit human erythrocyte system ASC noncompetitively with respect to L-alanine concentration, but approximated competitive inhibition with respect to Na+ concentration (apparent Ki = 2.0 and 0.9 mM, respectively). Similarly, harmaline noncompetitively inhibited L-alanine uptake by horse erythrocyte systems asc1 and asc2 (apparent Ki = 2.0 and 1.9 mM, respectively). In contrast, harmaline functioned as a competitive inhibitor of L-lysine uptake by system asc1 (apparent Ki = 2.6 mM). It is concluded that harmaline competes with Na+ for binding to system ASC and that a topographically similar harmaline inhibition site is present on system asc. This site does not however bind Na+, the asc1 transporter exhibiting normal L-alanine and L-lysine influx kinetics in the total absence of extracellular cations.

Both selenite and tellurite caused lysis of normal sheep erythrocytes in vitro. GSH-deficient sheep erythrocytes were considerably more resistant to haemolysis than normal cells. This effect was independent of the biochemical lesion responsible for GSH-deficiency (amino acid transport lesion or γ-glutamyl cysteine synthetase deficiency). These and other observations directly implicate intracellular GSH in the lytic mechanism. Selenite and tellurite-induced haemolysis therefore provides a simple method for detecting GSH-deficient cells. The lytic effect of selenite may explain some of the symptoms associated with selenium poisoning.

Site-specific binding of nitrobenzylthioinosine (NBMPR) to plasma membranes of some animal cells results in the inhibition of the facilitated diffusion of nucleosides. The present study showed that nucleoside transport in Novikoff UA rat hepatoma cells is insensitive to site-saturating concentrations of NBMPR. Equilibrium binding experiments demonstrated the presence of high-affinity sites for NBMPR in a membrane-enriched fraction from these cells. In the presence of uridine or dipyridamole, specific binding of NBMPR at these sites was inhibited. When Novikoff UA membranes were covalently labelled with [3H]NBMPR by using photoaffinity techniques, specifically bound radioactivity was incorporated exclusively into a polypeptide(s) with an apparent Mr of 72,000-80,000, determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Covalent labelling of this polypeptide was abolished in the presence of excess nitrobenzylthioguanosine (NBTGR) and reduced in the presence of adenosine, uridine or dipyridamole. The apparent Mr of the NBMPR-binding polypeptide in Novikoff UA cells is significantly higher than that reported for corresponding polypeptides in other cell types (Mr 45,000-66,000). When membrane-enriched preparations from S49 mouse lymphoma cells were photolabelled and mixed with labelled NovikoffUA membrane-enriched preparations, gel electrophoresis resolved the NBMPR-binding polypeptides from the two preparations.

Percoll density gradients were used to separate sheep erythrocytes according to cell age. Erythrocytes with low intracellular levels of glutathione (GSH) caused by an inherited deficiency of the System C amino acid transporter exhibited large age-realted decreases in GSH and K + content. In contrast, there was no age-related loss of intracellular GSH in normal sheep erythrocytes or in sheep erythrocytes with low GSH resulting from a diminished activity of γ-glutamylcysteine synthetase. Loss of GSH from amino acid transport-deficient erythrocytes was parallel by the progressive appearance of Heinz bodies in the cells, indicating an increased susceptibility to oxidative damage.

N6-(p-Azidobenzyl)adenosine (ABA) and nitrobenzylthioinosine (NBMPR) were employed as covalent probes of the nucleoside transport mechanism in human erythrocytes. NBMPR, a potent inhibitor of nucleoside transport, binds tightly (KD 0.3-1 nM) to specific sites on nucleoside transporter elements. ABA, a less potent inhibitor of uridine influx, competitively inhibited NBMPR binding (Ki 15 nM). [3H]ABA was bound tightly (KD 13.4 nM) but reversibly to sites on erythrocytes which appeared to be those which bind NBMPR. ABA binding was inhibited by uridine and adenosine. Irradiation with UV light caused site-bound [3H]ABA on erythrocyte membranes to become covalently bound and, similarly, photoactivation resulted in covalent attachment of membrane-bound [3H]NBMPR. In the presence of dithiothreitol, a free radical scavenger, photoactivation of the site-bound 3H-ligand on membranes depleted of extrinsic membrane proteins resulted in selective incorporation of 3H into band 4.5 of the membrane polypeptides which were resolved on sodium dodecyl sulfate-polyacrylamide gel electropherograms. This result, when considered with previous findings, indicates that the NBMPR-binding component of the nucleoside transport mechanism (or the entire mechanism, if the NBMPR site is an integral part) is a band 4.5 polypeptide.

Because Scotland is entangled in the social structure of the United Kingdom, the Scots' deepening disaffection from the government at Westminster poses serious, unresolved and escalating problems for the 'British' left. In circumstances where the 'British' working class is no longer a cohesive force, the advent of Scottish and Welsh nationalism is forcing the left in the United Kingdom to reappraise the prospects for 'British' socialism in the 1980s. It is, therefore, symbolically significant that the Highland workers at the Invergordon smelter immediately issued a public statement at the beginning of 1982 saying that they were occupying the plant for 'the sake of the Scottish nation'. The question of whether the agitation for Scottish selfgovernment is 'progressive' or 'reactionary' has always bobbed up during moments of crisis. From 1919 to 1939 the British Communist Party (CP) was always opposed to even the mildest form of 'devolution' for Scotland. This opposition sprang from two factors: that is, a particular way of looking at Scottish history and an abstract commitment to the unity of the British working class.

The small basic oligopeptide antibiotic, netropsin, can be successfully employed as an effective counterselecting agent in Saccharomyces cerevisiae. The use of the drug results in approximately a 35-fold enrichment of auxotrophic mutants in a mutagenized culture of yeast. The experimental procedure is quite simple and less time consuming than other presently used methods for indirect mutant selection in yeast.

8-Azidoadenosine was employed as a possible covalent probe of the erythrocyte nucleoside transporter. 8-Azidoadenosine was shown to enter human erythrocytes by a saturable mechanism (apparent Km for influx 80 microM) that was inhibited by nitrobenzylthioinosine (NBMPR), a potent inhibitor of nucleoside transport, and competitively inhibit uridine influx and NBMPR binding. Irradiation with UV light of human erythrocyte membranes or a partially purified preparation of the nucleoside transporter in the presence of [3H]8-azidoadenosine and dithiothreitol (as a free radical scavenger) resulted in selective covalent incorporation into the band 4.5 region of sodium dodecyl sulfate-polyacrylamide gels (Mr 66,000-45,000). Covalent labeling of band 4.5 was inhibited by adenosine, uridine, and inosine, but NBMPR had no effect. Surprisingly, D-glucose and cytochalasin B, but not L-glucose and cytochalasin E, blocked covalent attachment of the ligand. No incorporation of radioactivity into membranes from rabbit and pig erythrocytes was observed, cells which transport nucleosides rapidly, but have little or no functional glucose carrier. Limited treatment with trypsin of unsealed human erythrocyte membranes photolabeled with [3H]8-azidoadenosine yielded a single radioactive fragment of Mr 19,000, a pattern identical to that obtained with [3H]cytochalasin B-labeled membranes. These results suggest that, despite 8-azidoadenosine being a permeant for the nucleoside transporter, under photoactivation 8-azidoadenosine preferentially labeled the glucose carrier.

Amino acid transport was compared in human and in sheep erythrocytes. Kinetic studies established that human cells have three discrete amino acid transport systems, designated L, Ly + and ASC. The L system is partially stereospecific, with a preference for large neutral amino acids. L-leucine has a threefold lower apparent K m and a twofold smaller V max than D-leucine. Alanine, cysteine and possibly dibasic amino acids are transported by this route, but with a low affinity. The Ly + system is highly stereoselective, and specific for dibasic amino acids, including arginine. The ASC system is Na-dependent and selective for neutral amino acids of intermediate size. It has a particularly low apparent K m for cysteine and is stereospecific. Sheep erythrocytes lack these systems. Instead they possess an additional system (C system) responsible for the transport both of neutral and of dibasic amino acids, with cysteine as the optimal substrate. Although the substrate specificities of the human ASC and sheep C systems are similar, the sheep system does not require Na and has considerably higher apparent K m values. Dibasic amino acid transport (of lysine, but not of arginine) by the C system occurs with a low affinity.

The sensitivity of nucleoside transport by rat erythrocytes to inhibition by nitrobenzylthioinosine (NBMPR) and the slowly permeating organomercurial, p-chloromercuriphenyl sulfonate (pCMBS), was investigated. The dose response curve for the inhibition of uridine transport (100 microM) by NBMPR was biphasic--35% of the transport activity was inhibited with an IC50 value of 0.25 nM, but 65% of the activity remained insensitive to concentrations as high as 1 microM. These two components of uridine transport are defined as NBMPR-sensitive and NBMPR-insensitive, respectively. Uridine influx by both components was saturable and conformed to simple Michaelis-Menten kinetics, and was inhibited by other nucleosides. The uridine affinity of the NBMPR-sensitive transport component was threefold higher than for the NBMPR-insensitive transport mechanism (apparent Km for uridine 50 +/- 18 and 163 +/- 28 microM, respectively). The two transport systems also differed in their sensitivity to pCMBS. NBMPR-insensitive uridine transport was inhibited by pCMBS with an IC50 of approximately 25 microM, while 1 mM pCMBS had little effect on NBMPR-sensitive transport by intact cells. pCMBS inhibition was reduced in the presence of uridine and adenosine and reversed by the addition by beta-mercaptoethanol, suggesting that the pCMBS-sensitive thiol group is located on the exterior surface of the erythrocyte membrane within the nucleoside binding site of the transport system. Inhibition of uridine transport by NBMPR was associated with high-affinity [3H]NBMPR binding to the cell membrane (apparent Kd 46 +/- 25 pM). Binding of inhibitor to these sites was competitively blocked by uridine and inhibited by adenosine, thymidine, dipyridamole, dilazep and nitrobenzylthioguanosine. Assuming that each NBMPR-sensitive transport site binds a single molecule of NBMPR, the calculated translocation capacity of each site is 25 +/- 6 molecules/site per sec at 22 degrees C. pCMBS had no effect on [3H]NBMPR binding to intact cells but markedly inhibited binding to disrupted membranes indicating that the NBMPR-sensitive nucleoside transporter probably has a thiol group located on the inner surface of the membrane. Exposure of rat erythrocyte membranes to UV light in the presence of [3H]NBMPR resulted in covalent radiolabeling of a membrane protein(s) (apparent Mr on SDS gel electropherograms of 62,000). Labeling of this protein was abolished in the presence of nitrobenzylthioguanosine. We conclude that nucleoside transport by rat erythrocytes occurs by two facilitated-diffusion systems which differ in their sensitivity to inhibition by both NBMPR and pCMBS.

In a controversial article, 'Marxism, Nationalism and Scottish History', Dr. Tony Dickson attacks my political stance, my work as a professional historian and locks the two together into an inescapable vice. Because a historian's conception of the historical process is largely determined by his or her spiritual values, experience and world-outlook, the readers of the Journal of Contemporary History are entitled to know what lies behind Dr. Dickson's critique of my book, The Rousing of the Scottish Working Class, and article on 'Marxism and the Scottish National Question'. In 1980 Lawrence and Wishart, the British Communist Party publishers, issued a collection of essays on Scottish history entitled Scottish Capitalism: Class, State and Nation from before the Union to the Present. It was edited by Dr. Tony Dickson, a Marxist sociologist. He had not previously shown any interest in Scottish history. He also contributed a chapter or essay on the formation or making of the Scottish working class during the early period of

The human erythrocyte nucleoside transporter has been identified as a band 4.5 polypeptide (Mr 45,000-66,000) on the basis of reversible binding and photoaffinity labeling experiments with the nucleoside transport inhibitor, nitrobenzylthioinosine (NBMPR). In the present study, the NBMPR-binding protein was extracted from protein-depleted human erythrocyte "ghosts" with Triton X-100 and reconstituted into soybean phospholipid vesicles by a freeze-thaw-sonication procedure. The reconstituted proteoliposomes exhibited nitrobenzylthioguanosine (NBTGR)-sensitive [14C]uridine transport. A partially purified preparation of the NBMPR-binding protein, consisting largely of band 4.5 polypeptides, was also shown to have nucleoside transport activity. This band 4.5 preparation exhibited a 10-fold increase in uridine transport activity and a 7-fold increase in NBMPR-binding activity relative to the crude membrane extract. Uridine transport by the reconstituted band 4.5 preparation was saturable (apparent Km = 0.21 mM; Vmax = 9 nmol/mg of protein/5 s) and was inhibited by dipyridamole, dilazep, adenosine, and inosine. The vesicles reconstituted with the band 4.5 preparation also exhibited stereospecific glucose transport which was inhibited by cytochalasin B, but unaffected by NBTGR. In contrast, cytochalasin B was a poor inhibitor of NBTGR-sensitive uridine transport. These experiments implicate band 4.5 polypeptides in both nucleoside and sugar permeation.

Nucleosides cross the human erythrocyte membrane by a facilitated-diffusion process which is selectively inhibited by nanomolar concentrations of nitrobenzylthioinosine (NBMPR). The chemical asymmetry of the transporter was investigated by studying the effects of p- chloromercuriphenyl sulphonate (PCMBS) on uridine transport and high-affinity NBMPR binding in inside-out and right-side-out membrane vesicles, unsealed erythrocyte ghosts and intact cells. PCMBS was an effective inhibitor of the transporter (50% inhibition at 30 μM), but only when the organomercurial had access to the cytoplasmic membrane surface. PCMBS inhibition of NBMPR binding to ghosts was reversed by incubation with dithiothreitol. Both uridine and NBMPR were able to protect the transporter against PCMBS inhibition.

Red cells of adult sheep, like those of other ruminants, lack the calcium-activated potassium channel which is present in the membrane of human red cells. Since the activities of other transport systems in the sheep red cell are known to decrease during maturation of the cell or during development of the animal it was investigated whether the K + channel is present in red cells from younger animals or in reticulocytes. Using the divalent cation ionophore A23187 to increase the intracellular Ca of intact cells, it was found that the K + -selective channel is present in foetal red cells from the foetus or newborn animal but not in reticulocytes. The presence of the channel showed no dependence on the K + genotype of the sheep and was not associated with either “high K + ”-or “low K + ”-type Na + pump. No Ca 2+ -dependent change in K + permeability was found in red cells from either newborn or adult donkeys suggesting that its presence in the red cells of the foetus may not be general. The role of the K + channel in the mammalian red cell and the relationship between the K + channel and the Na + pump are discussed.

When reconstituted into proteoliposomes, the human erythrocyte nucleoside transporter catalysed nitrobenzylthioguanosine (NBTGR)-sensitive zero-trans influx of three different nucleosides at broadly similar rates (inosine, uridine greater than adenosine). However, proteoliposomes also exhibited high rates of NBTGR-insensitive uptake of adenosine, making this nucleoside unsuitable for reconstitution studies. Equivalent high rates of adenosine influx were observed in protein-free liposomes, establishing that this permeability pathway represents simple diffusion of nucleoside across the lipid bilayer. In contrast to adenosine, inosine and uridine exhibited acceptable rates of NBTGR-insensitive uptake. Of the two, inosine is the more attractive permeant for reconstitution experiments, having a 2.5-fold lower basal membrane permeability. Studies of nucleoside transport specificity in reconstituted membrane vesicles should take account of the widely different passive permeabilities of different nucleosides.

Intact human erythrocytes were irradiated in the frozen state with a high-energy electron beam. Nitrobenzylthioinosine-sensitive uridine influx, equilibrium exchange uridine influx and high-affinity nitrobenzylthioinosine binding were inactivated as a simple exponential function of the radiation dose, indicating an in situ target size of 122000. The results suggest that the nitrobenzylthioinosine-binding site(s) and the permeation site(s) of the transporter are present on the same transporter element.

The human erythrocyte nucleoside and glucose transporters, identified previously as band 4.5 peptides (apparent M r 66 000–45 000 ) on SDS-polyacrylamide gels, have been characterized in situ by radiation inactivation analysis. Target size analysis of lyophilized membranes indicates an apparent M r of 110 000 ± 12 000 and 124 000 ± 11 000 for the nucleoside and glucose carriers, respectively. These data suggest that both transporters exist in the membrane as dimers.

Binding of [125I]monoiodoinsulin to human astrocytoma cells (U-373 MG) was time dependent, reaching equilibrium after 1 h at 22 degrees C with equilibrium binding corresponding to 2.2 fmol/mg protein: this represents approximately 2,000 occupied binding sites per cell. The t1/2 of 125I-insulin dissociation at 22 degrees C was 10 min; the dissociation rate constant of 1.1 X 10(-2) s-1 was unaffected by a high concentration of unlabeled insulin (16.7 microM). Porcine insulin competed for specific 125I-insulin binding in a dose-dependent manner and Scatchard analysis suggested multiple affinity binding sites (higher affinity Ka = 4.4 X 10(8) M-1 and lower affinity Ka = 7.4 X 10(6) M-1). Glucagon and somatostatin did not compete for specific insulin binding. Incubation of cells with insulin (0.5 microM) for 2 h at 37 degrees C increased [2-14C]uridine incorporation into nucleic acid by 62 +/- 2% (n = 3) above basal. Cyclic AMP, in the absence of insulin, also stimulated nucleoside incorporation into nucleic acid [65 +/- 1% (n = 3)] above basal. Preincubation with cyclic AMP followed by insulin had an additive effect on nucleoside incorporation [160 +/- 4% (n = 3) above basal]. Dipyridamole (50 microM), a nucleoside transport inhibitor, blocked both basal and stimulated uridine incorporation. These studies confirm that human astrocytoma cells possess specific insulin receptors with a demonstrable effect of ligand binding on uridine incorporation into nucleic acid.

The properties of Na+-dependent L-alanine transport in human erythrocytes were investigated using K+ as the Na+ substitute. Initial rates of Na+-dependent L-alanine uptake (0.2 mM extracellular amino acid) for erythrocytes from 22 donors ranged from 40 to 180 mumol/litre of cells per h at 37 degrees C. Amino acid uptake over the concentration range 0.1-8 mM was consistent with a single saturable component of Na+-dependent L-alanine transport. Apparent Km and Vmax. values at 37 and 5 degrees C measured in erythrocytes from the same donor were 0.27 and 0.085 mM respectively, and 270 and 8.5 mumol/litre of cells per h respectively. The transporter responsible for this uptake was identified as system ASC on the basis of cross-inhibition studies with a series of 42 amino acids and amino acid analogues. Apparent Ki values for glycine, L-alpha-amino-n-butyrate, L-serine and L-leucine as inhibitors of Na+-dependent L-alanine uptake at 37 degrees C were 4.2, 0.12, 0.16 and 0.70 mM respectively. Reticulocytes from a patient with inherited pyruvate kinase deficiency were found to have a 10-fold elevated activity of Na+-dependent L-alanine uptake compared with erythrocytes from normal donors. Separation of erythrocytes according to cell density (cell age) established that even the oldest mature erythrocytes retained significant Na+-dependent L-alanine transport activity. Amino acid transport was, however, a more sensitive indicator of cell age than acetylcholinesterase activity. Erythrocytes were found to accumulate L-alanine against its concentration gradient (distribution ratio approx. 1.5 after 4 h incubation), an effect that was abolished in Na+-free media. Na+-dependent L-alanine uptake was shown to be associated with L-alanine-dependent Na+ influx, the measured coupling ratio being 1:1.

Evidence is presented that the red cell anion-exchange transport (Band 3) can selectively transport small neutral amino acids, including glycine, serine and cysteine, but not alanine, proline, valine and threonine. This transport is inhibited by micromolar concentrations of SITS (4-acetamido-4′-isothiocyanostilbene-2,2′-disulphonate), and increased by raising the pH from 6.5 to 8.5.

An inherited amino acid transport deficiency results in low concentrations of glutathione (GSH) in the erythrocytes of certain sheep. Earlier studies based on phenotyping according to GSH concentrations indicated that the gene TrH, which controls normal levels of GSH, behaves as if dominant or incompletely dominant to the allele Trh, which controls the GSH deficiency. The present papers shows that when sheep are classified according to amino acid transport activity, the TrH gene behaves as if codominant to Trh. Erythrocytes from sheep homozygous for the TrH gene exhibit rapid saturable L-alanine influx (apparent Km, 21.6 mM; Vmax, 22.4 mmol/liter cells/hr.). Cells from sheep homozygous for the Trh gene exhibit slow nonsaturable L-alanine uptake (0.55 mmol/liter cells/hr at 50mM extracellular L-alanine). Cells from heterozygous sheep show saturable L-alanine uptake with a diminished Vmax (apparent Km, 19.1 mM; Vmax, 12.7 mmol/liter cells/hr). These erythrocytes have a significantly lower GSH concentration than cells from TrH, TrH sheep but similar intracellular levels of dibasic amino acids.

SummaryFinnish Landrace sheep with low red cell GSH concentrations resulting from a defective transport system for certain arnino acids were crossed with Tasmanian Merino sheep with a red cell GSH deficiency due to impaired activity of the enzyme γ-glutamyl cysteine synthetase. Inheritance data showed that the two types of GSH deficiency were under independent genetic control. In the Finnish Landrace breed, the gene coding for the transport defect (Trn) was inherited as an autosomal recessive and sheep homozygous for this gene had high red cell concentrations of lysine and ornithine (Ly ×) as well as low levels of GSH. In the Tasmanian Merino breed the GSH deficiency behaved as if controlled by an autosomal dominant gene (GSHL). Backcross breeding experiments resulted in lambs which had inherited both types of GSH deficiency. Evidence suggested that such ‘double low’ GSH lambs had an impaired viability. In Tasmanian Merinos the GSH deficiency was established prior to birth. Newborn Finnish Landrace lambs were clearly separable into two types on the basis of their red cell lysine and ornithine content but not on their GSH concentrations.

(1974). The American civil war and the growth of Scottish republicanism. Labor History: Vol. 15, No. 1, pp. 98-108.

Mid-Victorian Scotland was a remarkably homogeneous society, and the milieu, in which the labour movement developed, had very long traditions of social repression and economic backwardness. A system of democracy inherited from the Calvinist revolution of 1559, social mobility and the comparatively superior educational opportunities of working class children were, in the considered opinion of a large number of journalists, clergymen and members of Parliament, the dominant characteristics of Scottish democracy. In practice, the educational opportunities and social mobility open to the working classes were severely circumscribed by the conditions industrial capitalism had engendered; and in the mid-1860s the labour movement, though influenced by the traditions – and the mythology – of Scottish democracy, looked to America for their model of a democratic society.

"'Tis a strange sort of poverty to be finding in a rich country." These words were spoken by an Irish immigrant lad in Ruth Sawyer's The Enchanted Schoolhouse. Though his words of wisdom referred to the inadequate and dilapidated school facilities he found in a wealthy and thriving city in America, they can well apply to another situation in America today: a land, wealthy with a multitude of fine books, and children who have not discovered them. At no previous time in history has there been such an astonishingly large number of children's books being published each year. In 1958 alone, there were 1557 titles published! Yet, in the midst of all this wealth there is great poverty, because so few people partake of these available riches. This poverty may be evidenced in at least three ways

Nitrobenzylthioniosine (NBMPR), a potent and specific inhibitor of nucleoside transport, is bound reversibly by high affinity sites on nucleoside transporter proteins of erythrocyte membranes and, upon photoactivation, NBMPR molecules become covalently bonded to the sites. This study showed that [ 3 H]NBMPR molecules reversibly bound to intact S49 and L5178Y mouse lymphoma cells became covalently bound upon exposure to UV light. Electrophoretic analysis of plasma membrane fractions from the labelled cells showed that 3 H was present in polypeptides which migrated as a major band with an apparent M r of 45000–65000.