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Thompson RG, Gottlieb A, Organ K, Koda J, Kisicki J, Kolterman OG. Pramlintide: a human amylin analogue reduced postprandial plasma glucose, insulin, and C-peptide concentrations in patients with type 2 diabetes. Diabet Med 1997; 14:547-55. [PMID: 9223392 DOI: 10.1002/(sici)1096-9136(199707)14:7<547::aid-dia390>3.0.co;2-u] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In order to determine the influence of a 5 h infusion of pramlintide compared to placebo on postprandial glucose, lactate, insulin, and C-peptide concentrations in patients with Type 2 diabetes, a single-blind, randomized, cross-over study was conducted in 24 patients; 12 treated with exogenous insulin and 12 managed with diet and/or oral hypoglycaemic agents. One hour after initiation of infusion, patients consumed a Sustacal test meal. The protocol was repeated on the following day with each patient receiving the alternate study medication. Pramlintide infusion in the insulin-treated patients resulted in statistically significant reductions in mean glucose, insulin, C-peptide, and lactate concentrations during the 4-h period after the Sustacal test meal. Pramlintide infusion also resulted in significant reductions of mean insulin, C-peptide, and lactate concentrations, but not glucose concentrations, in the patients treated with diet and/or oral hypoglycaemic agents. Within this latter group, reduction in postprandial glucose concentrations in individual patients correlated with glycated haemoglobin values. These results suggest that administration of pramlintide may improve glycaemic control in patients with Type 2 diabetes treated with insulin or poorly controlled on diet and/or oral hypoglycaemic agents.
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Thompson RG, Peterson J, Gottlieb A, Mullane J. Effects of pramlintide, an analog of human amylin, on plasma glucose profiles in patients with IDDM: results of a multicenter trial. Diabetes 1997; 46:632-6. [PMID: 9075803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The effects of subcutaneous administration of 10, 30, or 100 microg q.i.d. pramlintide, an analog of human amylin, on plasma glucose regulation in patients with IDDM were evaluated in a multicenter trial. The plasma glucose response to a Sustacal test meal was significantly reduced compared with placebo both after 1 week and after 2 weeks of administration of 30 or 100 microg pramlintide. In addition, 24-h mean plasma glucose concentrations were significantly lowered in patients receiving 30 microg of pramlintide for 2 weeks compared with placebo, while the 100-microg pramlintide dose did not reach statistical significance for the 24-h glucose profiles. At 10 microg, pramlintide had no effect on the 24-h glucose profile or on the plasma glucose response to a Sustacal test meal. The reduction in 24-h glucose concentrations and glucose concentrations after the Sustacal test meal observed at the 30-microg pramlintide dose was not accompanied by an increased incidence of hypoglycemic events. The most frequent adverse events were dose-related and involved transient upper gastrointestinal symptoms. A majority (>80%) of the patients who reported these adverse events during week 1 did not report them in week 2. These data indicate that pramlintide effectively reduces plasma glucose concentrations as reflected in both a 24-h glucose profile and a Sustacal test meal while maintaining an acceptable safety profile.
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Aruffo JF, Thompson RG, Gottlieb AA, Dobbins WN. An AIDS training program for rural mental health providers. Psychiatr Serv 1995; 46:79-81. [PMID: 7895128 DOI: 10.1176/ps.46.1.79] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A total of 194 mental health care providers in Arkansas, primarily from rural areas and small communities, participated in a four-hour training program designed to improve their knowledge about the psychosocial and neuropsychiatric aspects of HIV and AIDS. Participants' responses to questionnaires completed before and after training indicated that the program was successful in achieving its goal. However, only a minimal number of providers reported completing drug, alcohol, and sexual histories and AIDS risk assessments for any of their patients before the training occurred. The authors emphasize the importance of AIDS training for rural providers.
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Thompson RG, von Aderkas P. Somatic embryogenesis and plant regeneration from immature embryos of western larch. PLANT CELL REPORTS 1992; 11:379-385. [PMID: 24201537 DOI: 10.1007/bf00234365] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/1992] [Revised: 05/20/1992] [Indexed: 06/02/2023]
Abstract
Somatic embryogenesis was initiated from immature embryos of western larch (Larix occidentalis Nutt.) on media containing 2,4-dichlorophenoxyacetic acid and N6- benzyladenine. The effects of explant type and ammonium nitrate and glutamine concentrations on initiation were tested. Although 21-93% of explants rendered cultures in various experiments, only 3% yielded sustainable embryogenic lines. Excised embryos at the early cotyledonary stage were optimal for initiation. Maturation of somatic embryos was promoted by abscisic acid. Response to abscisic acid concentrations and duration of exposure to abscisic acid varied with genotype. Maximal results were obtained with 0.025 μ M abscisic acid for 1 to 2 weeks followed by individual culture on medium without growth regulators. Mature somatic embryos developed into shoots with roots. Plantlets have been established in peat.
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Rogers KR, Fernando JC, Thompson RG, Valdes JJ, Eldefrawi ME. Detection of nicotinic receptor ligands with a light addressable potentiometric sensor. Anal Biochem 1992; 202:111-6. [PMID: 1621972 DOI: 10.1016/0003-2697(92)90215-s] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The nicotinic acetylcholine receptor, purified from Torpedo electric organ, was coupled to a light addressable potentiometric sensor (LAPS) to form a LAPS-receptor biosensor. Receptor-ligand complexes containing biotin and urease were captured on a biotinylated nitrocellulose membrane via a streptavidin bridge and detected with a silicon-based sensor. Competition between biotinylated alpha-bungarotoxin and nonbiotinylated ligands formed the basis of this assay. This biosensor detected both agonists (acetylcholine, carbamylcholine, succinylcholine, suberyldicholine, and nicotine) and competitive antagonists (d-tubocurarine, alpha-bungarotoxin, and alpha-Naja toxin) of the receptor with affinities comparable to those obtained using radioactive ligand binding assays. Consistent with agonist-induced desensitization of the receptor, the LAPS-receptor biosensor reported a time-dependent increase in affinity for the agonist carbamylcholine as expected, but not for the antagonists.
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Rogers KR, Eldefrawi ME, Menking DE, Thompson RG, Valdes JJ. Pharmacological specificity of a nicotinic acetylcholine receptor optical sensor. Biosens Bioelectron 1991; 6:507-16. [PMID: 1910671 DOI: 10.1016/0956-5663(91)85048-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The pharmacological specificity of a nicotinic acetylcholine receptor (nAChR) optical biosensor was investigated using three fluorescein isothiocyanate (FITC)-tagged neurotoxic peptides that vary in the reversibility of their receptor inhibition: alpha-bungarotoxin (alpha-BGT), alpha-Naja toxin (alpha-NT), and alpha-conotoxin (GI) (alpha-CNTX). Kinetic analysis of the time course of binding of FITC-neurotoxins to the nAChR-coated fiber gave association rate constants (k+1) of 8.4 x 10(6) M-1 min-1 for FITC-alpha-BGT, 6.0 x 10(6) M-1 min-1 for FITC-alpha-NT and 1.4 x 10(6) M-1 min-1 for FITC-alpha-CNTX. The dissociation rate constants (k-1) for the three neurotoxins were 7.9 x 10(-3) min-1. 4.8 x 10(-2) min-1 and 8.0 x 10(-1) min-1 for FITC-alpha-BGT. FITC-alpha-NT and FITC-alpha-CNTX, respectively. The equilibrium dissociation constant (Kd) values for the three toxins. calculated from these rare constants, were similar to published values obtained from tissue responses or ligand binding assays. The optical signal generated by FITC-alpha-NT binding to the nAChR-coated fiber was effectively quenched by agonists and antagonists of the nAChR but not by most of the tested agonists and antagonists of muscarinic cholinergic, adrenergic, glutamatergic, serotonergic, dopaminergic or GABAergic receptors. Interestingly, 5-hydroxy-tryptamine, haloperidol and (+)cis-methyldioxolane gave significant inhibition of FITC-alpha-NT binding to the immobilized receptor. Equilibrium constants of inhibition (Ki) for d-tubocurarine (d-TC) and carbamylcholine (carb) were determined from competition studies using FITC-alpha-CNTX. FITC-alpha-NT or FITC-alpha-BGT as probes for receptor occupancy. When the more reversible probe FITC-alpha-CNTX was used, the Ki value for d-TC was an order of magnitude lower than those determined using the less reversible probes. Ki values for carb however, were independent of the FITC-toxin probe used.
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Ciochon RL, Piperno DR, Thompson RG. Opal phytoliths found on the teeth of the extinct ape Gigantopithecus blacki: implications for paleodietary studies. Proc Natl Acad Sci U S A 1990; 87:8120-4. [PMID: 2236026 PMCID: PMC54904 DOI: 10.1073/pnas.87.20.8120] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Identification of opal phytoliths bonded to the enamel surface of the teeth of Gigantopithecus blacki indicates that this extinct ape had a varied diet of grasses and fruits. By using the scanning electron microscope at magnifications of 2000-6000x specific opal phytoliths were observed and photographed on the fossilized teeth of an extinct species. Since opal phytoliths represent the inorganic remains of once-living plant cells, their documentation on the teeth of Gigantopithecus introduces a promising technique for the determination of diet in extinct mammalian species which should find numerous applications in the field of paleoanthropology as well as vertebrate paleontology.
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Holcombe JH, Conforti PM, Wong AC, Thompson RG, Draper MW. Biosynthetic human growth hormone in the treatment of growth hormone deficiency. ACTA PAEDIATRICA SCANDINAVICA. SUPPLEMENT 1990; 367:44-8. [PMID: 2220388 DOI: 10.1111/j.1651-2227.1990.tb11631.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A total of 309 previously untreated children with growth hormone deficiency (GHD) (219 boys, 90 girls; mean age 8.4 +/- 3.9 years, range 1.5-19 years) were treated for up to 3 years in an ongoing trial designed to examine the long-term efficacy and safety of biosynthetic somatropin (rhGH). The children were treated with rhGH, 0.06 mg/kg (0.16 IU/kg) three times weekly. In the prepubertal children, the mean height velocity increased during the first year from 3.8 +/- 1.8 cm/year to 8.9 +/- 2.2 cm/year (n = 188). During the second and third years, their height velocities were 7.1 +/- 1.1 (n = 147) and 6.3 +/- 1.2 cm/year (n = 64), respectively. The height velocity SDS increased from -2.5 +/- 1.9 before treatment to 3.1 +/- 2.6 during the first year of treatment in the prepubertal children. The mean pretreatment height velocity in those with idiopathic GHD (3.8 +/- 1.6 cm/year) did not differ from that in children with organic GHD (3.8 +/- 2.3 cm/year). In addition, the height velocities during the first year of therapy did not differ significantly with respect to the aetiology of GHD. For the children who entered puberty during the study, the mean height velocity increased from 3.0 +/- 1.7 cm/year before treatment to 8.4 +/- 2.3 cm/year during the first year of rhGH therapy. In the first year, the height velocity of children with a bone age of less than 5 years (9.4 +/- 2.3 cm/year) was significantly greater than that in children with a bone age of 5-10 years (8.4 +/- 1.8 cm/year) or greater than 10 years (7.8 +/- 2.2 cm/year: p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
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Thompson RG, Menking DE, Valdes JJ. Comparison of lindane, bicyclophosphate and picrotoxin binding to the putative chloride channel sites in rat brain and Torpedo electric organ. Neurotoxicol Teratol 1990; 12:57-63. [PMID: 1690344 DOI: 10.1016/0892-0362(90)90113-q] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The relative potencies of lindane, picrotoxin and several bicyclophosphate derivatives were compared in their ability to compete with 35S-t-butylbicyclophosphorothionate (35S-TBPS) binding sites in membranes derived from Torpedo electric organ and rat brain. Lindane proved to be ten times more potent in competing with 35S-TBPS binding in electric organ than rat brain, while the bicyclophosphate analogs displayed up to three orders of magnitude greater affinity for rat brain over electric organ. GABA inhibited 35S-TBPS binding in rat brain with moderate potency (IC50 = 30 microM), while unlabelled TBPS inhibited the binding of 3H-muscimol to the GABA receptor with an IC50 greater than 100 microM. The GABA receptor antagonist bicuculline increased 35S-TBPS binding in rat brain both in the presence and absence of 30 microM GABA. The results of the study are discussed in the context of a pharmacological discrimination between voltage-sensitive and receptor-gated Cl- channels in nervous tissue, with lindane and the i-propylbicyclophosphate derivative being the most selective compounds for discriminating between them.
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Preece PM, Ades A, Thompson RG, Brooks JH. Chlamydia trachomatis infection in late pregnancy: a prospective study. Paediatr Perinat Epidemiol 1989; 3:268-77. [PMID: 2788879 DOI: 10.1111/j.1365-3016.1989.tb00378.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
During a 1-year period, 3309 women were screened in pregnancy for Chlamydia trachomatis infection. A cervical swab was taken and chlamydial antigen was detected, using a monoclonal antibody ELISA technique, in 198 women (6%). The prevalence of chlamydial infection was high in women under 20 years (14.5%), single women (14.2%) and black women (16.8%). Binomial regression of these data estimates a relative risk of 2.9 for women under 20 years compared with women aged 25 and over. There was an interaction between race and marital status with a high risk in single white and single asian women (2.3, 4.5 respectively) but a similar risk in black single and black married women (3.0, 4.0 respectively). Parity and social class did not effect the prevalence of antigen carriage. There was no demonstrable effect of maternal antigen carriage on outcome of pregnancy, gestation or admission to neonatal unit. Infants of 174 antigen-positive mothers were followed-up. Tissue culture for Chlamydia trachomatis was positive in 43 (24%) infants. Complications occurred in 23 (53%): 17 had conjunctivitis, three had lower respiratory tract infection and three both complications. Amongst 131 chlamydia-negative infants, complications occurred in 21 (16%). Since this infection, in infants, responds promptly to erythromycin therapy, screening and treatment in pregnancy will convey little benefit in prevention of perinatal morbidity or perinatal mortality.
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Han SH, Madden JF, Thompson RG, Strauss SH, Siegel LM, Spiro TG. Resonance Raman studies of Escherichia coli sulfite reductase hemoprotein. 1. Siroheme vibrational modes. Biochemistry 1989; 28:5461-71. [PMID: 2673346 DOI: 10.1021/bi00439a022] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Resonance Raman (RR) spectra are reported for the hemoprotein subunit (SiR-HP) of Escherichia coli NADPH-sulfite reductase (EC 1.8.1.2) in various ligation and redox states. Comparison of the RR spectra of extracted siroheme and the mu-oxo FeIII dimer of octaethylisobacteriochlorin with those of mu-oxo FeIII octaethylchlorin dimer and mu-oxo FeIII octaethylporphyrin dimer demonstrates that many siroheme bands can be correlated with established porphyrin skeletal modes. Depolarization measurements are a powerful tool in this correlation, since the 45 degrees rotation of the C2 symmetry axis of the isobacteriochlorin ring relative to the chlorin system results in reversal of the polarization properties (polarized vs anomalously polarized) of bands correlating with B1g and B2g modes of porphyrin. Various SiR-HP adducts (CO, NO, CN-, SO3(2-] show upshifted high-frequency bands, characteristic of the low-spin state and consistent with the expected core size sensitivity of the skeletal modes. Fully reduced unliganded SiR-HP (both siroheme and Fe4S4 cluster reduced) in liquid solution displays RR features comparable to those of high-spin ferrous porphyrins; on freezing, the RR spectrum changes, reflecting an apparent mixture of siroheme spin states. At intermediate reduction levels in solution a RR species is observed whose high-frequency bands are upshifted relative to oxidized and fully reduced SiR-HP. This spectrum, thought to arise from the "one-electron" state of SiR-HP (siroheme reduced, cluster oxidized), may be due to S = 1 FeII siroheme.
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Abstract
In a prospective study of Chlamydia trachomatis infection in pregnancy, 198 mothers positive for chlamydial antigen were identified; the infants of 174 were followed for up to six months and C trachomatis was recovered in cell culture from 43 infants (25%). Conjunctivitis occurred in significantly more infants who were positive for C trachomatis (20 of 43, 47%) than in those who were negative (18 of 131, 14%). There were also significantly more lower respiratory tract infections among infants with positive cultures (six of 43, 14%, compared with three of 131, 2%). The chlamydial antigen enzyme linked immunosorbent assay (ELISA) was positive in 61 of 131 infants from whom C trachomatis was not recovered in cell culture. False positive results were usually associated with the isolation of Staphylococcus aureus from samples of pharyngeal aspirate. Our results confirm that C trachomatis infection is a common cause of neonatal conjunctivitis, and respiratory infection in the first few months of life, with an incidence of 8.2/1000 live births. Because the infection is easily treated by oral erythromycin, however, screening during pregnancy is not warranted.
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Valdes JJ, Thompson RG, Wolff VL, Menking DE, Rael ED, Chambers JP. Inhibition of calcium channel dihydropyridine receptor binding by purified Mojave toxin. Neurotoxicol Teratol 1989; 11:129-33. [PMID: 2471918 DOI: 10.1016/0892-0362(89)90051-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Mojave toxin, the principal toxic component of the venom of the Mojave rattlesnake Crotalus scutulatus scutulatus, is a protein complex of about 22,000 mol. wt. The mechanism of action of this potent (LD50 = 0.039 micrograms/g, mouse, IV) neurotoxin is a matter of conjecture, but physiologic data suggest a presynaptic site of action with disruption of stimulus-secretion coupling and neurotransmitter release. The selectivity of Mojave toxin's effect on several ion channels involved in neurotransmission was assessed in the present study using competitive radioisotopic binding procedures. Synaptic membranes from rat brain were used to assess the toxin's interaction with Ca++ and Cl- channels while membrane fragments from the Torpedo fish electric organ were used to determine toxin interaction with the nicotinic acetylcholine receptor-coupled Na+ channel. Mojave toxin was found to irreversibly inhibit 3H-nitrendipine binding to dihydropyridine receptors associated with Ca++ channels in rat brain, but had no effect on radioligand binding in the Na+ and Cl- channel assays. Saturation analysis of the binding further showed that the effects of MoTX on dihydropyridine binding were noncompetitive, with MoTX producing a decrease in both the affinity and density of 3H-nitrendipine sites. These results are consistent with the hypothesis that MoTX acts selectively on Ca++ channel function and that this interaction occurs via an allosteric mechanism in which MoTX binds to a membrane site that is topologically distinct from the dihydropyridine receptor.
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Thompson RG, Conforti P, Holcombe J. Biosynthetic human growth hormone: current status and future questions. J Endocrinol Invest 1989; 12:35-9. [PMID: 2809097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Human growth hormone derived from human pituitaries resulted in excellent growth in children with growth hormone deficiency but limited supplies in many countries prevented treatment of all children, delayed the onset of therapy, and/or forced the use of doses that may have been less than optimal. Recent advances in technology allow the production of byosynthetic human growth hormone (hGH) by recombinant methods resulting in increased supplies of hormone. More than 200 previously untreated children with growth hormone deficiency have been evaluated for two years or longer while receiving biosynthetic natural sequence hGH (somatropin). The mean growth velocity of 3.6 cm/yr prior to therapy increased to 8.8 cm/yr after one year and 7.25 cm/yr in the second year. Growth response was inversely related to age when calculated as cm/yr. This response paralleled the normal decrease in growth velocity as children approach puberty. Children with hGH deficiency who had previously received replacement hGH were enrolled in a double-blind study using either 0.06 or 0.10 mg/kg thrice weekly for 12 months. Growth rate was significantly greater with the higher dose during the first six months but not during the second six month period. The use of a higher dose of hGH must be individualized as not all patients have accelerated growth with the increased dose and the mean group response is not permanent. Multiple questions remain unanswered after three decades of treating growth hormone deficiency. Are the current criteria for diagnosis of growth hormone deficiency appropriate? What dose of hGH is correct? Do children need increases in replacement therapy as their height approaches normal?(ABSTRACT TRUNCATED AT 250 WORDS)
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Hall RA, Thompson RG. Landfilling with domestic waste. JOURNAL OF THE ROYAL SOCIETY OF HEALTH 1987; 107:192-4. [PMID: 3119847 DOI: 10.1177/146642408710700513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Strauss SH, Thompson RG. Rates of pi-electron oxidation and reduction of free base and Zn(II) porphyrins, chlorins, and isobacteriochlorins. J Inorg Biochem 1986; 27:173-7. [PMID: 3760858 DOI: 10.1016/0162-0134(86)80058-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The rates of pi-electron oxidation and reduction of two homologous series of free base and Zn(II) porphyrins, chlorins, and isobacteriochlorins were studied by chronocoulometry at a platinum disk electrode. The macrocycles were octaethylporphyrin, tetraphenylporphyrin, and the chlorins and isobacteriochlorins derived therefrom. The rates were found to vary to within a factor of 3, and some consistent trends are noted. However, the most important conclusion of this work is that pi-electron redox processes for these macrocycles occur at essentially the same rate, despite the previously noted large differences in pi-electron redox potentials.
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Holmes CS, Koepke KM, Thompson RG. Simple versus complex performance impairments at three blood glucose levels. Psychoneuroendocrinology 1986; 11:353-7. [PMID: 3786640 DOI: 10.1016/0306-4530(86)90021-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
By using a visual reaction time paradigm, we sought to determine if disruption of relatively simple responding (finger tapping or letter recognition) or more complex responding (choice reaction time) would occur in response to blood glucose deviations. Glucose levels were maintained in 24 male diabetics to within 4% of the following targeted concentrations: 55 mg/dl (hypoglycemia), 110 mg/dl (euglycemia/control), and 300 mg/dl (hyperglycemia). The results indicate that simple motor and perceptual skills were not affected by blood glucose alterations, while more complex cognitive processing required significantly longer response latencies during hypoglycemia. Performance impairments occurred independently of disease duration and control, and without documented neuropathy, underscoring the sensitivity of some cognitive skills to acute glucose fluctuations.
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Holmes CS, Karlsson JA, Thompson RG. Social and school competencies in children with short stature: longitudinal patterns. J Dev Behav Pediatr 1985; 6:263-7. [PMID: 4066961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Longitudinal evaluation of 47 children with short stature secondary to growth hormone deficiency (GHD), constitutional delay (CD), and Turner's syndrome (TS) was undertaken approximately 3 years after initial assessment. Parent ratings of social and school competence indicated a developmental trend of poorer adjustment during early adolescence (ages 12 and 14), which was preceded (age 9) and followed (age 17) by age-appropriate functioning. Evaluation of social competence scores suggested that large organized group activities were avoided, although children had close friends with whom they interacted regularly. Children with short stature obtained age-expected scores for their involvement in solitary activities (i.e., hobbies and household chores) and tended to participate in individual sports (i.e., fishing, swimming), consistent with a pattern of withdrawal from large groups. Younger children with CD evidenced academic functioning at least 1 SD higher than children from all other groups, and this age-related effect may explain performance inconsistencies reported previously with other groups of CD children. Of the children studied, girls with TS experienced the greatest academic difficulty.
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Rubin JR, Yao JS, Thompson RG, Bergan JJ. Management of infection of major amputation stumps after failed femorodistal grafts. Surgery 1985; 98:810-5. [PMID: 4049252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A retrospective review was performed of 174 patients who underwent 199 lower-extremity amputations for unreconstructable vascular insufficiency from 1976 to 1983 at the Northwestern University Medical Center. This study was initiated to identify the cause of amputation wound healing complications and secondary ascending prosthetic graft infection, as well as to propose a plan of management for the failed prosthetic grafts at the time of major limb amputation. Ninety-eight amputations were performed primarily, 12 were performed secondary to graft infection, and 89 were performed in patients who had previously undergone infrainguinal arterial bypass procedures. At the time of amputation, graft management consisted of high transection and suture ligation, allowing the graft to retract into the substance of the stump and away from the skin suture line and weight-bearing area of the limb. Delayed stump healing was noted to occur more commonly in the group who had undergone previous bypasses as opposed to those who had undergone primary amputation (34.8% versus 14.3%). Fourteen graft infections developed in 89 patients after amputation (15.7%), which is significantly higher than the overall 1.4% incidence of lower-extremity bypass infections that occurred during the same interval in patients with intact extremities. In addition, it was found that when infected grafts in amputated limbs were completely removed, stump healing without recurrent wound and graft sepsis was better than when treated locally or with partial graft removal. We therefore recommend removal of a thrombosed graft with an infected wound or an infected graft at the time of major limb amputation to decrease the incidence of wound complications and graft infection.
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Bishop CW, Kendrick NC, Santek DA, Thompson RG, DeLuca HF. Computer analysis of double-labeled two-dimensional electrophoresis gels. Anal Biochem 1985; 148:133-48. [PMID: 4037296 DOI: 10.1016/0003-2697(85)90638-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A computerized process for the automatic analysis of double-label autoradiography after two-dimensional polyacrylamide gel electrophoresis has been developed. Matching fluorographs and autoradiographs produced from gels containing 3H- and 14C-labeled proteins are digitized by a rotating drum densitometer and analyzed by the Man-computer Interactive Data Analysis System III. This system locates corresponding protein spots in the films with edge-detection algorithms, converts spot density readings to isotopic disintegrations by reference to standard curves, and computes a 3H:14C ratio for each spot in the gels. On the average, calculated ratios are accurate to approximately 9% for test strips of polyacrylamide gel containing uniform mixtures of 3H and 14C. Values obtained for two-dimensional gels containing n protein spots with a known 3H:14C ratio of 8.6 +/- 0.1 are as follows: 8.1 +/- 1.4 (n = 268), 8.8 +/- 2.1 (n = 278), 9.1 +/- 1.7 (n = 245), and 8.8 +/- 2.2 (n = 223). The computer process greatly reduces the time required to precisely compare two complex protein mixtures and has sufficient precision to detect a doubling in the biosynthesis of any individual protein.
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Glass AD, Thompson RG, Bordeleau L. Regulation of NO(3) Influx in Barley : Studies Using NO(3). PLANT PHYSIOLOGY 1985; 77:379-81. [PMID: 16664062 PMCID: PMC1064523 DOI: 10.1104/pp.77.2.379] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Short-term (10 minutes) measurements of plasmalemma NO(3) (-) influx (phi(oc)) into roots of intact barley plants were obtained using (13)NO(3) (-). In plants grown for 4 days at various NO(3) (-) levels (0.1, 0.2, 0.5 millimolar), phi(oc) was found to be independent of the level of NO(3) (-) pretreatment. Similarly, pretreatment with Cl(-) had no effect upon plasmalemma (13)NO(3) (-) influx. Plants grown in the complete absence of (13)NO(3) (-) (in CaSO(4) solutions) subsequently revealed influx values which were more than 50% lower than for plants grown in NO(3) (-). Based upon the documented effects of NO(3) (-) or Cl(-) pretreatments on net uptake of NO(3) (-), these observations suggest that negative feedback from vacuolar NO(3) (-) and/or Cl(-) acts at the tonoplast but not at the plasmalemma. When included in the influx medium, 0.5 millimolar Cl(-) was without effect upon (13)NO(3) (-) influx, but NH(4) (+) caused approximately 50% reduction of influx at this concentration.
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Thompson RG. Hyperventilation, hypokalemia, and SIDS. HOSPITAL PRACTICE (OFFICE ED.) 1984; 19:84E-84H, 84L, 84P-84Q passim. [PMID: 6094603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Clarke DR, Harper IA, Thompson RG. The detection of Escherichia coli heat-labile enterotoxin by enzyme-linked immunosorbent assay. J Infect 1984; 9:244-51. [PMID: 6396337 DOI: 10.1016/s0163-4453(84)90508-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
An enzyme linked immunosorbent assay (ELISA) technique was modified and used to detect heat-labile (LT) enterotoxigenic Escherichia coli (ETEC) from specimens of faeces sent to a routine diagnostic laboratory. Strains of LT ETEC were detected in eight of 250 (3.2%) diarrhoeal stools but were not found in 110 non-diarrhoeal stools. All eight patients found to have LT ETEC were travellers returning with diarrhoea. LT ETEC was the most common bacterial pathogen found (15.4%) in this group of patients, exceeding Campylobacter sp. (5.8%) and Salmonella sp. (7.7%). The ELISA technique was simple to perform and visual readings were found to be reliable.
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Holmes CS, Koepke KM, Thompson RG, Gyves PW, Weydert JA. Verbal fluency and naming performance in type I diabetes at different blood glucose concentrations. Diabetes Care 1984; 7:454-9. [PMID: 6499638 DOI: 10.2337/diacare.7.5.454] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The effect of serum glucose alterations on selected verbal skills was examined in a group of diabetic men between 18 and 35 yr of age. An artificial insulin infusion system was used to set and maintain glucose concentrations during testing at each of three levels: hypoglycemia (55 mg/dl), euglycemia (110 mg/dl), and hyperglycemia (300 mg/dl). Subjects were used as their own controls, with performance at euglycemia serving as the comparison standard. A double-blind crossover design was employed as described in Holmes et al. (see ref. 14). Results showed significantly disrupted naming or labeling skills at hypoglycemia, with a trend toward poorer performance at hyperglycemia. During hypoglycemia, rate of responding was slowed from 6% to 18%, compared with euglycemic performance, but accuracy was not impaired. In contrast, word recognition skills were not affected by deviations in glucose. These performance effects were not correlated with duration of disease except for one of the five tests administered. This one exception, on the most difficult task, was less notable than the general finding of no relation between disease duration (from 6 mo to 17.5 yr) and test performance. Thus, in addition to considering long-term consequences of blood glucose alterations, clinicians and diabetic patients may wish to consider acute neuropsychological consequences of disrupted euglycemia.
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