Showing papers by "University of Vermont published in 1990"
TL;DR: In this article, a conceptual framework that organizes the purchasing arrangements for repetitively used industrial supplies assume many different forms, and a transaction cost analysis is used to organize these forms.
Abstract: Purchasing arrangements for repetitively used industrial supplies assume many different forms. Drawing on transaction cost analysis, the authors advance a conceptual framework that organizes these ...
1,682 citations
TL;DR: It is shown that voltage-dependent Ca channels in the steady state can be open and very sensitive to membrane potential changes in a range that occurs in resistance arteries with tone.
Abstract: Resistance arteries exist in a maintained contracted state from which they can dilate or constrict depending on need. In many cases, these arteries constrict to membrane depolarization and dilate to membrane hyperpolarization and Ca-channel blockers. We discuss recent information on the regulation of arterial smooth muscle voltage-dependent Ca channels by membrane potential and vasoconstrictors and on the regulation of membrane potential and K channels by vasodilators. We show that voltage-dependent Ca channels in the steady state can be open and very sensitive to membrane potential changes in a range that occurs in resistance arteries with tone. Many synthetic and endogenous vasodilators act, at least in part, through membrane hyperpolarization caused by opening K channels. We discuss evidence that these vasodilators act on a common target, the ATP-sensitive K (KATP) channel that is inhibited by sulfonylurea drugs. We propose the following hypotheses that presently explain these findings: 1) arterial smooth muscle tone is regulated by membrane potential primarily through the voltage dependence of Ca channels; 2) many vasoconstrictors act, in part, by opening voltage-dependent Ca channels through membrane depolarization and activation by second messengers; and 3) many vasodilators work, in part, through membrane hyperpolarization caused by KATP channel activation.
1,080 citations
TL;DR: It is concluded that factor VII is most likely a zymogen, just as are the other proenzymes of the blood clotting process, and the kinetic constants obtained for the various coagulation reactions determined in vitro provide some insights into how these pathways may function in vivo.
801 citations
TL;DR: Available data do not support the concept that low-level exposure to asbestos is a health hazard in buildings and schools, and the concentration of asbestos fibers in air, type of asbestos, and size of fibers must be considered in evaluation of potential health risks.
Abstract: Asbestos is a commercial term for a group of fibrous minerals often associated with the development of pulmonary interstitial fibrosis (asbestosis), lung cancer, and malignant mesothelioma in occupationally exposed individuals. The pathogenicity of different forms of asbestos varies--long, thin amphibole fibers are most pathogenic, particularly in the induction of mesothelioma. Available data do not support the concept that low-level exposure to asbestos is a health hazard in buildings and schools. The concentration of asbestos fibers in air, type of asbestos, and size of fibers must be considered in evaluation of potential health risks.
690 citations
TL;DR: It is reported here that temperature-sensitive mutants defective in genes CDC42 and CDC43, like cdc24 mutants, fail to bud but continue growth at restrictive temperature, and thus arrest as large unbudded cells, supporting the hypothesis that the events associated with budding and those of the nuclear cycle represent two independent pathways within the cell cycle.
Abstract: Budding in the yeast Saccharomyces cerevisiae involves a polarized deposition of new cell surface material that is associated with a highly asymmetric disposition of the actin cytoskeleton. Mutants defective in gene CDC24, which are unable to bud or establish cell polarity, have been of great interest with regard to both the mechanisms of cellular morphogenesis and the mechanisms that coordinate cell-cycle events. To gain further insights into these problems, we sought additional mutants with defects in budding. We report here that temperature-sensitive mutants defective in genes CDC42 and CDC43, like cdc24 mutants, fail to bud but continue growth at restrictive temperature, and thus arrest as large unbudded cells. Nearly all of the arrested cells appear to begin nuclear cycles (as judged by the occurrence of DNA replication and the formation and elongation of mitotic spindles), and many go on to complete nuclear division, supporting the hypothesis that the events associated with budding and those of the nuclear cycle represent two independent pathways within the cell cycle. The arrested mutant cells display delocalized cell-surface deposition associated with a loss of asymmetry of the actin cytoskeleton. CDC42 maps distal to the rDNA on chromosome XII and CDC43 maps near lys5 on chromosome VII.
588 citations
TL;DR: It is reported that arterial dilations in response to CGRP are partially reversed by blockers of the ATP-sensitive potassium channel (KATP), glibenclamide1012 and barium10,13 and proposed that activation of KATP channels underlies a substantial part of the relaxation produced by C GRP.
Abstract: Calcitonin gene-related peptide (CGRP) is a 37-amino-acid peptide produced by alternative processing of messenger RNA from the calcitonin gene. CGRP is one of the most potent vasodilators known. It occurs in and is released from perivascular nerves and has been detected in the blood stream, suggesting that it is important in the control of blood flow. The mechanism by which it dilates arteries is not known. Here, we report that arterial dilations in response to CGRP are partially reversed by blockers of the ATP-sensitive potassium channel (K(ATP)), glibenclamide and barium. We also show that CGRP hyperpolarizes arterial smooth muscle and that blockers of K(ATP) channels reverse this hyperpolarization. Finally, we show that CGRP opens single K+ channels in patches on single smooth muscle cells from the same arteries. We propose that activation of K(ATP) channels underlies a substantial part of the relaxation produced by CGRP.
465 citations
TL;DR: Eleven of 258 thioguanine-resistant T cell clones from five of the six MS patients who were tested proliferated in response to human myelin basic protein without prior in vitro exposure to this antigen.
Abstract: Gene mutation in vivo in human T lymphocytes appears to occur preferentially in dividing cells. Individuals with multiple sclerosis (MS) are assumed to have one or more populations of diving T cells that are being stimulated by autoantigens. Mutant T cell clones from MS patients were isolated and tested for reactivity to myelin basic protein, an antigen that is thought to participate in the induction of the disease. The hypoxanthine guanine phosphoribosyltransferase (hprt) clonal assay was used to determine mutant frequency values in MS patients with chronic progressive disease. Eleven of 258 thioguanine-resistant (hprt-) T cell clones from five of the six MS patients who were tested proliferated in response to human myelin basic protein without prior in vitro exposure to this antigen. No wild-type clones from these patients, nor any hprt- or wild-type clones from three healthy individuals responded to myelin basic protein. Thus, T cell clones that react with myelin basic protein can be isolated from the peripheral blood of MS patients.
451 citations
TL;DR: Using a number of in vitro assays, researchers have been able to elucidate the action mechanism of the UvrABC nuclease complex, which represents a unique form of protein-DNA interaction.
402 citations
TL;DR: The mechanism of water-stress-induced xylem embolism was studied in three species of conifers: Abies balsamea (L.) Mill, Picca rubens Sarg, and Juniperus virginiana L..
Abstract: . The mechanism of water-stress-induced xylem embolism was studied in three species of conifers: Abies balsamea (L.) Mill., Picca rubens Sarg, and Juniperus virginiana L. Each species showed a characteristic relationship between xylem tension and the loss of hydraulic conductivity by air embolism. Abics balsamea and Picca rubens began to embolize at tensions between 2 and 3 MPa and were completely non-conducting between 3 and 4 MPa. Juniperus virginiana was least vulnerable, beginning to embolize at 4 and still retaining approximately 10% conductivity at 10 MPa. As with a previous study of the vessel-bearing Accr saccharum Marsh., a brief perfusion of branch segments with an oxalic acid and calcium solution (10 and 0.1 mol m−3. respectively) increased the vulnerability of the xylem to embolism; this was especially pronounced in Abies balsamea. In order to test whether embolism was caused by aspiration of air into functional tracheids from neighbouring embolized, ones (the ‘air-seeding’hypothesis), hydrated branch segments were injected with air at various pressures and measured for embolism. Results supported the air-seeding hypothesis because the relationship between injection pressure and embolism for both native and oxalic-calcium-treated segments was essentially the same as for embolism induced by xylem tension. Structural and experimental evidence suggested the air seeding occurred through inter-tracheid pit membranes when the thickened torus region of the membrane became displaced from its normal sealing position over the pit aperture. Thus, the embolism-inducing tension may be a function of pit membrane flexibility. This tension is of ecological significance because it reflects to some extent the range of xylem tensions to which a species is adapted.
353 citations
Book•
02 Aug 1990TL;DR: The Citizenship in the Political Community: An Analytical Statement as discussed by the authors is an analytic statement that states that "the citizen in the political community is an agent of the political system." The Citizenship and Community in the Civic-Republican Tradition.
Abstract: 1. Introduction Part I Citizenship and Community: An Analytical Statement 2. The Citizen in the Political Community Part II Citizenship and Community in the Civic-Republican Tradition 3. Machiavelli: Citizenship and Glory 4. Rousseau: Freedom, Virtue and Happiness 5. Hegel: Rational Freedom in the Ethical Community 6. Toqueville: Citizenship in Town and State Part III Citizenship and Community in the Modern World 7. The Modern Relevance of the Civic-Republican Tradition 8. Citizenship in Modern Democratic Theory
327 citations
TL;DR: In this article, the authors examined the relationship between the Debt-Equity Ratio (DER) and actual debt covenant restrictions for a random sample of U.S. firms and found that several versions of the DER capture the existence and tightness of retained earnings restrictions and the existence of net tangible asset and working capital restrictions.
TL;DR: Cessation of cigarette smoking by pregnant women may reduce the risk of preterm premature rupture of membranes, and two variables remained in the model as independent risk factors: antepartum vaginal bleeding and current cigarette smoking.
01 Jan 1990
TL;DR: The effects of abstinence from tobacco can produce significant distress, are similar to the classical withdrawal syndromes of opiates and sedatives, and account for much of the inability of smokers to stop.
Abstract: Many smokers, ex-smokers, and scientists have strong opinions about the effects of abstinence from tobacco. Some believe the effects are mild, are not true withdrawal phenomena, and have little to do with the inability of smokers to stop. Others believe abstinence effects can produce significant distress, are similar to the classical withdrawal syndromes of opiates and sedatives, and account for much of the inability of smokers to stop.
TL;DR: This group comprised 8.5% of patients of all ages admitted for stroke, 2.3 times the proportion observed in the National Survey of Stroke, and deserve an extensive but tailored evaluation, which should include angiography and echocardiography.
Abstract: Strokes in young adults are uncommon and often a diagnostic challenge. A retrospective study of strokes due to intracerebral hemorrhage, subarachnoid hemorrhage, or cerebral infarction was undertaken. We reviewed the medical records of 113 young patients aged 15-45 years who were admitted to the Medical Center Hospital of Vermont with a diagnosis of stroke between 1982 and 1987. This group comprised 8.5% of patients of all ages admitted for stroke, 2.3 times the proportion observed in the National Survey of Stroke. Nontraumatic intracerebral hemorrhage was diagnosed in 46 young patients (41%); the main causes included aneurysms, arteriovenous malformations, hypertension, and tumors. Subarachnoid hemorrhage was found in 19 young patients (17%); the majority were due to aneurysms. The remaining 48 young patients (42%) had cerebral infarction, the majority due to cardiogenic emboli and premature atherosclerosis. Mitral valve prolapse, the use of oral contraceptives, alcohol drinking, and migraine were infrequent sole causes of cerebral infarction in the absence of other risk factors. The case-fatality rate for this group of young patients with stroke was 20.4% compared with 23.9% for the National Survey of Stroke. Young adults with stroke deserve an extensive but tailored evaluation, which should include angiography and echocardiography.
TL;DR: The shape of the menisci and the orientation of the collagen fibers are optimal for weight bearing and shock absorption and an attempt should be made to save viable meniscus when performing knee surgery.
TL;DR: Research guidelines are proposed for investigations in multiple sclerosis, including suggestions for sampling methods, population characterization, and control groups as well as a recommended core battery of neuropsychological tests for use in this population.
Abstract: Acquisition of scientific information regarding the neuropsychological aspects of multiple sclerosis has been hampered by studies using small, inadequately described patient and control samples and a wide array of cognitive test procedures that hinder multicenter data pooling. Based on a review of key issues of clinical need and experimental interest, research guidelines are proposed for investigations in this burgeoning research area. The guidelines include suggestions for sampling methods, population characterization, and control groups as well as a recommended core battery of neuropsychological tests for use in this population. It is hoped that these guidelines will advance knowledge about the neuropsychology of multiple sclerosis by helping to promote sound experimental design, facilitate cross-study comparison, and encourage multicenter collaborative efforts.
TL;DR: Unphosphorylated myosin acts as a load to slow down the rate at which actin is moved by the faster cycling phosphorylated cross-bridges, and the observed modulation of actin velocity as a function of copolymer composition can be accounted for by a model based on mechanical interactions between cross- bridges.
Abstract: Although it is generally believed that phosphorylation of the regulatory light chain of myosin is required before smooth muscle can develop force, it is not known if the overall degree of phosphorylation can also modulate the rate at which cross-bridges cycle. To address this question, an in vitro motility assay was used to observe the motion of single actin filaments interacting with smooth muscle myosin copolymers composed of varying ratios of phosphorylated and unphosphorylated myosin. The results suggest that unphosphorylated myosin acts as a load to slow down the rate at which actin is moved by the faster cycling phosphorylated cross-bridges. Myosin that was chemically modified to generate a noncycling analogue of the "weakly" bound conformation was similarly able to slow down phosphorylated myosin. The observed modulation of actin velocity as a function of copolymer composition can be accounted for by a model based on mechanical interactions between cross-bridges.
TL;DR: The activation of human factor V by factor Xa and thrombin was studied by functional assessment of cofactor activity and sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by either autoradiography of 125I-labeled factor V activation products or Western blot analyses of unlabeled factorV activation products.
Abstract: The activation of human factor V by factor Xa and thrombin was studied by functional assessment of cofactor activity and sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by either autoradiography of 125I-labeled factor V activation products or Western blot analyses of unlabeled factor V activation products. Cofactor activity was measured by the ability of the factor V/Va peptides to support the activation of prothrombin. The factor Xa catalyzed cleavage of factor V was observed to be time, phospholipid, and calcium ion dependent, yielding a cofactor with activity equal to that of thrombin-activated factor V (factor Va). The cleavage pattern differed markedly from the one observed in the bovine system. The factor Xa activated factor V subunits expressing cofactor activity were isolated and found to consist of peptides of Mr 220,000 and 105,000. Although thrombin cleaved the Mr 220,000 peptide to yield peptides previously shown to be products of thrombin activation, cofactor activity did not increase. N-Terminal sequence analysis confirmed that both factor Xa and thrombin cleave factor V at the same bond to generate the Mr 220,000 peptide. The factor Xa dependent functional assessment of 125I-labeled factor V coupled with densitometric analyses of the cleavage products indicated that the cofactor activity of factor Xa activated factor V closely paralleled the appearance of the Mr 220,000 peptide. This observation facilitated the study of the kinetics of factor V activation by allowing the activation of factor V to be monitored by the appearance of the Mr 220,000 peptide (factor Xa activation) or the Mr 105,000 peptide (thrombin activation). Factor Xa catalyzed activation of factor V obeyed Michaelis-Menten kinetics and was characterized by a Km of 10.4 nM, a kcat of 2.6 min-1, and a catalytic efficiency (kcat/Km) of 4.14 X 10(6) M-1 s-1. The thrombin-catalyzed activation of factor V was characterized by a Km of 71.7 nM, a kcat of 14.0 min-1, and a catalytic efficiency of 3.26 X 10(6) M-1 s-1. This indicates that factor Xa is as efficient an enzyme toward factor V as thrombin.
TL;DR: Initiation of DNA replication in mammalian chromosomes uses the same replication fork mechanism previously described in a variety of prokaryotic and eukaryotic genomes, suggesting that mammalian chromosomes also utilize specific cis-acting sequences as origins ofDNA replication.
TL;DR: Western blot analysis using the monoclonal antibody mAb 1F8 (specific for the insulin-regulatable glucose transporter) demonstrated increased glucose transporter densities in plasma membranes from insulin-treated hind limb skeletal muscle compared with untreated tissues, while microsomal membranes from the diabetes-treated hamstring skeletal muscle had a concomitant decrease in transporter density.
TL;DR: The data indicate that the overall cerebral arterial dilator response to ACh is determined by the combined effects of membrane hyperpolarization, which closes voltage-dependent calcium channels, and the actions of a second endothelial factor, probably endothelium-derived relaxing factor.
Abstract: Acetylcholine (ACh)-induced hyperpolarization of cerebral arteries requires a functional endothelium. The hyperpolarization is reversed by potassium-channel blockers. The goal of this study was to determine whether the hyperpolarization is causally related to endothelium-dependent dilation of isolated cerebral arteries. ACh hyperpolarized rabbit middle cerebral arteries by up to 19 mV. The hyperpolarizations were sustained and did not occur in arteries without endothelial cells or in the presence of potassium-channel inhibitors (3 x 10(-6) M glibenclamide or 5 x 10(-5) M BaCl2). ACh-induced dilator responses were inhibited but not abolished by glibenclamide or BaCl2. Methylene blue also inhibited the dilator responses, and a combination of glibenclamide or BaCl2 and methylene blue greatly diminished the dilation. Nitric oxide relaxed but did not hyperpolarize the vascular smooth muscle cells, and BaCl2 had no effect on the nitric oxide-induced relaxations. These data indicate that the overall cerebral arterial dilator response to ACh is determined by the combined effects of membrane hyperpolarization, which closes voltage-dependent calcium channels, and the actions of a second endothelial factor, probably endothelium-derived relaxing factor.
TL;DR: The results suggest that lower levels of IGF-I in aging men are related at least in part to diminished physical activity, and multiple factors contribute to the age-related decline.
Abstract: To examine the hypothesis that a lower level of physical activity influences the age-related decline in insulinlike growth factor-I (IGF-I), we measured serum concentrations in healthy nonobese younger and older men, characterized for maximal aerobic capacity ( max) and energy expended in leisure time physical activity. To examine the independent influencec of physical activity on IGF-I relative to other lifestyle variables, we also determined fat-free weight, percent body fat, body fat distribution (waist to hip and waist to thigh ratios), and habitual caloric intake in our population. IGF–I was 33% lower (P < 0.01) in older men than in younger men, inversely related to percent body fat (r = –0.55) and indices of upper body fat distribution (waist to hip ratio, r = –0.45; waist to thigh ratio, r = –0.47), and positively related to max (r = 0.64) and leisure time physical activity (r = 0.45; P < 0.01). IGF-I was not related to fat-free weight or daily caloric intake. After controlling for the effects of a...
TL;DR: There were no indications in any of the samples of a stronger relation between negative events and psychological symptoms for adolescent females than males, and there was little evidence that instrumentality or expressivity moderated the relations between negative Events and Psychological symptoms.
Abstract: Examined the roles of gender, instrumentafity, and expressivity as moderators of the relations between stressful events and psychological symptoms in samples o f junior high (n = 93), senior high (n = 140), and college students (n = 145). Female adolescents in all three samples reported more overall negative events than did males. Females in the junior and senior high samples reported more negative interpersonal stresses than did males. However, there were no indications in any of the samples of a stronger relation between negative events and psychological symptoms for adolescent females than males. Further, there was little evidence that instrumentality or expressivity moderated the relations between negative events and psychological symptoms. In each sample, certain stresses were most strongly related to psychological symptoms: family stresses in the junior high, peer stresses in the senior high, and academic stresses in the college sample. Implications of the findings for developmental changes in stress during adolescence are discussed.
TL;DR: It is shown that stimulation of the D1 receptors activates the facilitation Ca2+ currents in the absence of pre-depolarizations or repetitive activity, and that activation by D1 agonists is mediated by cyclic AMP and protein kinase A.
Abstract: Facilitation calcium channels in unstimulated bovine chromaffin cells are normally quiescent but are activated by large pre-depolarizations or by repetitive depolarization in the physiological range. The activation of these 27-pS dihydropyridine-sensitive channels by repetitive stimulation, such as by increased splanchnic nerve activity, can lead to an almost twofold increase in Ca2+ current in these cells. This increase in Ca2+ current is of probable physiological importance in stimulating rapid catecholamine secretion in response to danger or stress. We have identified D1 dopaminergic receptors on bovine chromaffin cells by fluorescence microscopy. Here we show that stimulation of the D1 receptors activates the facilitation Ca2+ currents in the absence of pre-depolarizations or repetitive activity, and that activation by D1 agonists is mediated by cyclic AMP and protein kinase A. The recruitment of facilitation Ca2+ channels by dopamine may form the basis of a positive feedback loop mechanism for catecholamine secretion.
TL;DR: The results of the re-analysis indicated that response requirement and reinforcer magnitude, the constituents of unit price, have functionally equivalent effects on drug consumption and that a positively decelerating demand curve is produced as unit price increases.
TL;DR: Neurolucida is a new software package for performing 3-D neuron mapping and tracing to 0.5 micron precision through the oculars of a microscope and has a video mode compatible with frame grabbers, thereby permitting its application to video microscopy.
TL;DR: The human placental gene, which the authors designate CDC42Hs, complements the cdc42-1 mutation in S. cerevisiae, which suggests that this GTP-binding protein is the human homolog of the yeast protein.
Abstract: We have isolated cDNA clones from a human placental library that code for a low molecular weight GTP-binding protein originally designated Gp (also called G25K). This identification is based on comparisons with the available peptide sequences for the purified human Gp protein and the use of two highly specific anti-peptide antibodies. The predicted amino acid sequence of the protein is very similar to those of various members of the ras superfamily of low molecular weight GTP-binding proteins, including the N-, Ki-, and Ha-ras proteins (30-35% identical), the rho proteins (approximately 50% identical), and the rac proteins (approximately 70% identical). The highest degree of sequence identity (80%) is found with the Saccharomyces cerevisiae cell-division-cycle protein CDC42. The human placental gene, which we designate CDC42Hs, complements the cdc42-1 mutation in S. cerevisiae, which suggests that this GTP-binding protein is the human homolog of the yeast protein.
TL;DR: This is the first report of stimulated generation of 3-phosphorylated phosphoinositides in anucleate cells and suggests a role for a GTP-binding protein in promoting phosphatidylinositide 3-kinase activity(ies).
TL;DR: Genes Scored in Red Cells, T-lymphoc ytes, and T-Lymphocytes are revealed.
Abstract: INTROD UCTION . . . . . . . . ... . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . 306 THE CELL S yS TEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306 Red Blood Cells . . . . . .. . . . . . . . . . . . . . . . . . . .... . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . ... . . .. . . . . ... . . . . .. . . 306 T-Lymphocytes . . . . .. . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307 THE GENETIC SyS TEMS . . . . . . . .. . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308 Genes Scored in Red Cells . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . 308 Genes Sco re d in T-lymphoc ytes . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .. . .... . . 308 THE AS SAyS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309 HbS 309 GPA .... . . . . . . . ...... . . . . . . . . ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....... . ... . . ... . . . . . . . . . . . . . . ... . . . 309 hprt . .. . . . . . . . . . . .. . . . . . . . . . . . . .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...... . . . . . . . . . . . . . . . . . . . . ..... . . 310 HLA .. . . . . . . . . . . ... . . . . . . . . . . .. ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . ... . . . . . . . . . . . . . . . . .. . . .. . . . . 310 QUANTITATIVE MEAS UREMENTS OF Vf OR Mf IN H UMAN SOMATIC CELLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1 1 HbS 312 GPA . . . . . . . . . .. . . . . . . . . . . . . . . . . ... . . . . . . . . . . .. . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 312 hprt . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . ..... . . . . . ... . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . . . 313 HLA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314 RELATIONSHIPS BETWEEN MEAS URED M UTANT FREQUENCIES AND PROB AB LE M UTATION FREQUENCIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314 MOLEC ULAR ANALYSES OF IN VIVO SOM ATIC M UTATION S IN H UMANS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315 hpr t Mutations... . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . .. . . . . . . .. . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . 315 HLA Mutations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319 CONCLUS IONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319
TL;DR: In this article, the authors report a convenient pathway to N-tert-butoxycarbonyl-α,ω-alkanediamines 2a-e [H2N(CH2)χNHBOC; χ=2, 3, 4, 5 and 6; (75-90% yields) by treatment of the corresponding α,ω-,alkanedienine with di-terto-butyl dicarbonate in dioxane as the solvent.