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Okunade KS, Oluwole AA, Adegbesan-Omilabu MA. A Study on the Association between Low Maternal Serum Magnesium Level and Preterm Labour. Adv Med 2014; 2014:704875. [PMID: 26556421 PMCID: PMC4590970 DOI: 10.1155/2014/704875] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 03/18/2014] [Accepted: 03/24/2014] [Indexed: 11/17/2022] Open
Abstract
Objectives. The study was aimed to assess the association between low maternal serum magnesium levels and preterm labour. Methods. It is a cross-sectional case-control study in which eligible participants were pregnant women admitted in labour within the labour ward complex of a Lagos tertiary hospital. Relevant data were extracted from the case records of these women and blood samples were obtained from all participants and serum magnesium levels measured. Results. The study showed that 36% of the study patients had varying degrees of hypomagnesaemia. The relative risk indicates that preterm labour is 1.83 times higher among the patients with low serum magnesium (less than 1.6 mg/dL). The mean difference in serum magnesium levels in both groups was statistically significant (P<0.05). Conclusion. We can infer that low serum magnesium (hypomagnesaemia) is associated with preterm onset of labour. We can, also from this finding, formulate a proposition that would help in preventing preterm labour and birth with the use of prophylactic oral magnesium supplementation among patients with higher risk for development of preterm labour.
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Affiliation(s)
- Kehinde S. Okunade
- Department of Obstetrics & Gynaecology, Lagos University Teaching Hospital, Lagos, Nigeria
| | - Ayodeji A. Oluwole
- Department of Obstetrics & Gynaecology, Lagos University Teaching Hospital, Lagos, Nigeria
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Arruda AP, Oliveira GM, Carvalho DP, De Meis L. Thyroid hormones differentially regulate the distribution of rabbit skeletal muscle Ca2 + -ATPase (SERCA) isoforms in light and heavy sarcoplasmic reticulum. Mol Membr Biol 2009; 22:529-37. [PMID: 16373324 DOI: 10.1080/09687860500412257] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The sarcoplasmic reticulum (SR) is composed of two fractions, the heavy fraction that contains proteins involved in Ca2+ release, and the light fraction enriched in Ca(2+)-ATPase (SERCA), an enzyme responsible for Ca2+ transport from the cytosol to the lumen of SR. It is known that in red muscle thyroid hormones regulate the expression of SERCA 1 and SERCA 2 isoforms. Here we show the effects of thyroid hormone on SERCA expression and distribution in light and heavy SR fractions from rabbit white and red muscles. In hyperthyroid red muscle there is an increase of SERCA 1 and a decrease of SERCA 2 expression. This is far more pronounced in the heavy than in the light SR fraction. As a result, the rates of Ca(2+)- ATPase activity and Ca(2+)-uptake by the heavy vesicles are increased. In hypothyroidism we observed a decrease in SERCA 1 and no changes in the amount of SERCA 2 expressed. This promoted a decrease of both Ca(2+)-uptake and Ca(2+)-ATPase activity. While the major differences in hyperthyroidism were found in the heavy SR fraction, the effects of hypothyroidism were restricted to light SR fraction. In white muscle we did not observe any significant changes in either hypo- or hyperthyroidism in both SR fractions. Thus, the regulation of SERCA isoforms by thyroid hormones is not only muscle specific but also varies depending on the subcellular compartment analyzed. These changes might correspond to the molecular basis of the altered contraction and relaxation rates detected in thyroid dysfunction.
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Arruda AP, Nigro M, Oliveira GM, de Meis L. Thermogenic activity of Ca2+-ATPase from skeletal muscle heavy sarcoplasmic reticulum: The role of ryanodine Ca2+ channel. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1768:1498-505. [PMID: 17466935 DOI: 10.1016/j.bbamem.2007.03.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2006] [Revised: 03/15/2007] [Accepted: 03/19/2007] [Indexed: 11/30/2022]
Abstract
The sarcoplasmic reticulum Ca(2+) ATPase 1 (SERCA 1) is able to handle the energy derived from ATP hydrolysis in such a way as to determine the parcel of energy that is used for Ca(2+) transport and the fraction that is converted into heat. In this work we measured the heat production by SERCA 1 in the two sarcoplasmic reticulum (SR) fractions: the light fraction (LSR), which is enriched in SERCA and the heavy fraction (HSR), which contains both the SERCA and the ryanodine Ca(2+) channel. We verified that although HSR cleaved ATP at faster rate than LSR, the amount of heat released during ATP hydrolysis by HSR was smaller than that measured by LSR. Consequently, the amount of heat released per mol of ATP cleaved (DeltaH(cal)) by HSR was lower compared to LSR. In HSR, the addition of 5 mM Mg(2+) or ruthenium red, conditions that close the ryanodine Ca(2+) channel, promoted a decrease in the ATPase activity, but the amount of heat released during ATP hydrolysis remained practically the same. In this condition, the DeltaH(cal) values of ATP hydrolysis increased significantly. Neither Mg(2+) nor ruthenium red had effect on LSR. Thus, we conclude that heat production by SERCA 1 depends on the region of SR in which the enzyme is inserted and that in HSR, the DeltaH(cal) of ATP hydrolysis by SERCA 1 depends on whether the ryanodine Ca(2+) channel is opened or closed.
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Affiliation(s)
- Ana Paula Arruda
- From the Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Cidade Universitária, RJ, Brazil
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4
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Kabbara AA, Stephenson DG. Effects of Mg2+ on Ca2+ handling by the sarcoplasmic reticulum in skinned skeletal and cardiac muscle fibres. Pflugers Arch 1994; 428:331-9. [PMID: 7529401 DOI: 10.1007/bf00724515] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The influence of myoplasmic Mg2+ (0.05-10 mM) on Ca2+ accumulation (net Ca2+ flux) and Ca2+ uptake (pump-driven Ca2+ influx) by the intact sarcoplasmic reticulum (SR) was studied in skinned fibres from the toad iliofibularis muscle (twitch portion), rat extensor digitorum longus (EDL) muscle (fast twitch), rat soleus muscle (slow twitch) and rat cardiac trabeculae. Ca2+ accumulation was optimal between 1 and 3 mM Mg2+ in toad fibres and reached a plateau between 1 and 10 mM Mg2+ in the rat EDL fibres and between 3 and 10 mM Mg2+ in the rat cardiac fibres. In soleus fibres, optimal Ca2+ accumulation occurred at 10 mM Mg2+. The same trend was obtained with all preparations at 0.3 and 1 microM Ca2+. Experiments with 2,5-di-(tert-butyl)-1,4-benzohydroquinone, a specific inhibitor of the Ca2+ pump, revealed a marked Ca2+ efflux from the SR of toad iliofibularis fibres in the presence of 0.2 microM Ca2+ and 1 mM Mg2+. Further experiments indicated that the SR Ca2+ leak could be blocked by 10 microM ruthenium red without affecting the SR Ca2+ pump and this allowed separation between SR Ca2+ uptake and SR Ca2+ accumulation. At 0.3 microM Ca2+, Ca2+ uptake was optimal with 1 mM Mg2+ in the toad iliofibularis and rat EDL fibres and between 1 and 10 mM Mg2+ in the rat soleus and trabeculae preparations. At higher [Ca2+] (1 microM), Ca2+ uptake was optimal with 1 mM Mg2+ in the iliofibularis fibres and between 1 and 3 mM Mg2+ in the EDL fibres.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- A A Kabbara
- School of Zoology, La Trobe University, Bundoora, Victoria, Australia
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5
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da Costa AG, Madeira VM. Proton ejection as a major feature of the Ca(2+)-pump. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1189:181-8. [PMID: 8292623 DOI: 10.1016/0005-2736(94)90064-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
H+ ejection and Ca2+ uptake promoted by the sarcoplasmic reticulum (SR) Ca(2+)-pump are similarly stimulated by millimolar Mg2+. This cannot be assigned to enhanced Ca2+ uptake and H+ displacement from internal metal binding sites since: (1) loading SR vesicles with high Mg2+ concentrations does not impair H+ ejection; (2) loading SR vesicles with Mn2+ does not depress H+ ejection occurring during Mn2+ uptake; (3) H+ ejection occurs even when Ca2+ accumulation inside the vesicles is prevented with Ca2+ ionophores. It is concluded that the Ca(2+)-pump promotes an active Ca2+/H+ countertransport stimulated by Mg2+. Finally, a mechanism for Ca2+ translocation is proposed in basic physico-chemical terms.
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Affiliation(s)
- A G da Costa
- Centro de Biologia Celular e Departamento de Bioquímica, Coimbra, Portugal
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6
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Blatter LA. Intracellular free magnesium in frog skeletal muscle studied with a new type of magnesium-selective microelectrode: interactions between magnesium and sodium in the regulation of [Mg]i. Pflugers Arch 1990; 416:238-46. [PMID: 2381762 DOI: 10.1007/bf00392059] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The application of a new type of intracellular magnesium-selective microelectrode based on the neutral carrier ETH5214 to measure intracellular free magnesium ([Mg]i) in frog skeletal muscle fibers is reported. At room temperature (18-20 degrees C) the average values for [Mg]i was 0.93 mmol/l (pMgi = 3.03 +/- 0.42, SD; n = 38 experiments). The regulation of [Mg]i was studied by measuring [Mg]i and [Na]i with ion-selective microelectrodes during alterations of the membrane potential and the transmembrane sodium and magnesium gradients. Depolarization by increasing external [K] from 2.5 mmol/l to 12.5 mmol/l did not significantly influence [Mg]i. Increasing extracellular [Mg] from 1 mmol/l to 10 and 20 mmol/l caused a concentration-dependent rise in [Mg]i and a decrease in [Na]i, whereas removal of external magnesium did not affect [Mg]i. Removal of external [Na] caused an increase in [Mg]i and a decrease of [Na]i. The results show that [Mg]i in frog skeletal muscle is not in thermodynamic equilibrium and suggest that a Na/Mg exchange mechanism may be involved in maintaining low levels of [Mg]i.
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Affiliation(s)
- L A Blatter
- Department of Pharmacology, Mayo Foundation, Rochester, MN 55905
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Gilchrist JS, Katz S, Belcastro AN. Improved resolution of the initial fast phase of heavy sarcoplasmic reticulum Ca2+ uptake by Ca2+:antipyrylazo III dual-wavelength spectroscopy. Biochem Biophys Res Commun 1990; 168:364-71. [PMID: 2109610 DOI: 10.1016/0006-291x(90)91717-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The effect of ATP upon difference absorbance due to Ca2+ and Mg2+ complexation with the metallochromic dye, Antipyrylazo III (AP III), was investigated. At divalent cation concentrations appropriate for Sarcoplasmic Reticulum Ca2+ transport, wavelengths (greater than 670 nm) were found whereupon the addition of up to 1mM nucleotide did not alter divalent cation:AP III difference absorbance. At these sample wavelengths an initial rapid uptake of Ca2+ by Heavy SR (HSR) was clearly resolved by dual wavelength spectroscopy of Ca2+:dye difference absorbance. Elimination of ATP interference of Ca2+:AP III absorbance by Mg2+ elevation (3-10mM) was shown to be an inappropriate general strategy for AP III spectroscopic studies of HSR Ca2+ transport due to Mg2+ inhibition of ryanodine receptor mediated Ca2+ release.
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Affiliation(s)
- J S Gilchrist
- Faculty of Graduate Studies, University of British Columbia, Vancouver, Canada
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8
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Mészáros LG, Ikemoto N. Non-identical behavior of the Ca2(+)-ATPase in the terminal cisternae and the longitudinal tubules fractions of sarcoplasmic reticulum. EUROPEAN JOURNAL OF BIOCHEMISTRY 1989; 186:677-81. [PMID: 2481584 DOI: 10.1111/j.1432-1033.1989.tb15259.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The kinetics of Ca2+ dissociation from and binding to the Ca2(+)-ATPase and the coupled tryptophan fluorescence changes were compared in the heavy and the light sarcoplasmic reticulum (SR) fractions. It was found that in the light SR both the dissociation of Ca2+ from the Ca2(+)-ATPase and the coupled tryptophan fluorescence change took place in a biphasic fashion, but they were monophasic in the heavy SR. On the other hand, the time courses of both the Ca2+ binding and the coupled tryptophan fluorescence increase were biphasic, and virtually indistinguishable between the heavy and the light SR fractions. Submicromolar ruthenium red altered the kinetics of both the Ca2+ dissociation and the coupled fluorescence change in heavy, but not in light SR; the monophasic time course characteristic of the heavy fraction became biphasic, similar to that found for light SR in the absence of ruthenium red. Extraction of non-ATPase proteins from the heavy SR vesicles also changed the kinetics of the Ca2+ dissociation-coupled fluorescence decrease in the heavy SR from monophasic to biphasic. These results suggest that the difference between the heavy and light SR Ca2(+)-ATPase in the Ca2+ dissociation kinetics is most probably produced by a ruthenium-red-sensitive interaction of the Ca2(+)-ATPase with additional protein(s), which is/are present exclusively in the heavy SR, rather than being due to a difference inherent to the Ca2(+)-ATPase polypeptide itself.
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Affiliation(s)
- L G Mészáros
- Department of Muscle Research, Boston Biomedical Research Institute, MA
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9
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Fernandez-Belda F, Soler F, Gomez-Fernandez JC. Quinacrine inhibits the calcium-induced calcium release in heavy sarcoplasmic reticulum vesicles. BIOCHIMICA ET BIOPHYSICA ACTA 1989; 985:279-85. [PMID: 2529908 DOI: 10.1016/0005-2736(89)90413-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Quinacrine is a fluorescence probe useful for studying the effect of local anesthetics. The interaction of quinacrine and sarcoplasmic reticulum membranes measured by fluorescence spectroscopy indicates the presence of a saturable binding site. Typical local anesthetics are able to displace quinacrine bound to heavy sarcoplasmic reticulum membranes. The effectiveness of that displacement decreases in the order dibucaine greater than tetracaine greater than benzocaine greater than lidocaine greater than procaine greater than procainamide, indicating that the size and hydrophobicity of quinacrine are major determinants in the binding process. The use of radioactive tracer and a rapid filtration technique reveals that quinacrine interacts, at lower concentrations, with sarcoplasmic reticulum membranes by blocking the Ca2+-induced Ca2+ release. Higher quinacrine concentrations also affect the Ca2+-pump activity.
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Affiliation(s)
- F Fernandez-Belda
- Departamento de Bioquimica, Facultad de Veterinaria, Universidad de Murcia, Spain
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10
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Palade P, Dettbarn C, Brunder D, Stein P, Hals G. Pharmacology of calcium release from sarcoplasmic reticulum. J Bioenerg Biomembr 1989; 21:295-320. [PMID: 2546933 DOI: 10.1007/bf00812074] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Calcium release from sarcoplasmic reticulum (SR) has been elicited in response to additions of many different agents. Activators of Ca2+ release are here tentatively classified as activators of a Ca2+-induced Ca2+ release channel preferentially localized in SR terminal or as likely activators of other Ca2+ efflux pathways. Some of these pathways may be associated with several different mechanisms for SR Ca2+ release that have been postulated previously. Studies of various inhibitors of excitation-contraction coupling and of certain forms of SR Ca2+ release are summarized. The sensitivity of isolated SR to certain agents is unusually affected by experimental conditions. These effects can seriously undermine attempts to anticipate effects of the same pharmacological agents in situ. Finally, mention is made of a new preparation ("sarcoballs") designed to make the pharmacological study of SR Ca2+ release more accessible to electrophysiologists, and some concluding speculations on the future of SR pharmacology are offered.
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Affiliation(s)
- P Palade
- Department of Physiology, University of Texas Medical Branch, Galveston 77550
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11
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Affinity labeling of calmodulin-binding proteins in skeletal muscle sarcoplasmic reticulum. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(18)37642-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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12
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Mészáros LG, Brown KL, Ikemoto N. 4',6-Diamidino-2-phenylindole, a novel conformational probe of the sarcoplasmic reticulum Ca2+ pump, and its effect on Ca2+ release. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)60843-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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13
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Palade P. Drug-induced Ca2+ release from isolated sarcoplasmic reticulum. I. Use of pyrophosphate to study caffeine-induced Ca2+ release. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)45548-2] [Citation(s) in RCA: 65] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Gomes da Costa A, Madeira VM. Magnesium and manganese ions modulate Ca2+ uptake and its energetic coupling in sarcoplasmic reticulum. Arch Biochem Biophys 1986; 249:199-206. [PMID: 2943223 DOI: 10.1016/0003-9861(86)90575-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
ATP hydrolysis, either coupled or uncoupled from Ca2+ uptake by sarcoplasmic reticulum (SR), is essentially independent of Mg2+ (millimolar range) up to 50 mM. Conversely, a sharp enhancement of Ca2+ uptake by Mg2+ is observed with a consequent increase of pumping efficiency (Ca2+ per ATP). Therefore, Mg2+ modulates pumping efficiency through the molecular mechanism of the pump itself. Manganese ions also stimulate Ca2+ uptake with an apparent efficiency lower than that of Mg2+. Additionally, Mn2+ competes with Ca2+ for the pump system and is accumulated into SR vesicles. Although the affinity of the pump is about three orders of magnitude higher for Ca2+ than for Mn2+, the capacity of the vesicles for Mn2+ is about three times that commonly observed for Ca2+. It is concluded that Mg2+ (millimolar range) couples ATP hydrolysis to Ca2+ uptake and that active transport of cations (Ca2+ and Mn2+) can proceed without a compensatory countertransport of a divalent cation. Finally, it is suggested that the SR pump operates physically as general cation translocator instead of as a Ca2+-specific pump, as commonly assumed.
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Fleschner CR, Kraus-Friedmann N. The effect of Mg2+ on hepatic microsomal Ca2+ and Sr2+ transport. EUROPEAN JOURNAL OF BIOCHEMISTRY 1986; 154:313-20. [PMID: 2935394 DOI: 10.1111/j.1432-1033.1986.tb09399.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The ATP-dependent uptake of Ca2+ by rat liver microsomal fraction is dependent upon Mg2+. Studies of the Mg2+ requirement of the underlying microsomal Ca2+-ATPase have been hampered by the presence of a large basal Mg2+-ATPase activity. We have examined the effect of various Mg2+ concentrations on Mg2+-ATPase activity, Ca2+ uptake, Ca2+-ATPase activity and microsomal phosphoprotein formation. Both Mg2+-ATPase activity and Ca2+ uptake were markedly stimulated by increasing Mg2+ concentration. However, the Ca2+-ATPase activity, measured concomitantly with Ca2+ uptake, was apparently unaffected by changes in the Mg2+ concentration. In order to examine the apparent paradox of Mg2+ stimulation of Ca2+ uptake but not of Ca2+-ATPase activity, we examined the formation of the Ca2+-ATPase phosphoenzyme intermediate and formation of a Mg2+-dependent phosphoprotein, which we have proposed to be an attribute of the Mg2+-ATPase activity. We found that Ca2+ apparently inhibited formation of the Mg2+-dependent phosphoprotein both in the absence and presence of exogenous Mg2+. This suggests that Ca2+ may inhibit (at least partially) the Mg2+-ATPase activity. However, inclusion of the Ca2+ inhibition of Mg2+-ATPase activity in the calculation of Ca2+-ATPase activity reveals that this effect is insufficient to totally account for the stimulation of Ca2+ uptake by Mg2+. This suggests that Mg2+, in addition to stimulation of Ca2+-ATPase activity, may have a direct stimulatory effect on Ca2+ uptake in an as yet undefined fashion. In an effort to further examine the effect of Mg2+ on the microsomal Ca2+ transport system of rat liver, the interaction of this system with Sr2+ was examined. Sr2+ was sequestered into an A23187-releasable space in an ATP-dependent manner by rat liver microsomal fraction. The uptake of Sr2+ was similar to that of Ca2+ in terms of both rate and extent. A Sr2+-dependent ATPase activity was associated with the Sr2+ uptake. Sr2+ promoted formation of a phosphoprotein which was hydroxylamine-labile and base-labile. This phosphoprotein was indistinguishable from the Ca2+-dependent ATPase phosphoenzyme intermediate. Sr2+ uptake was markedly stimulated by exogenous Mg2+, but the Sr2+-dependent ATPase activity was unaffected by increasing Mg2+ concentrations. Sr2+ uptake and Sr2+-dependent ATPase activity were concomitantly inhibited by sodium vanadate. In contrast to Ca2+, Sr2+ had no effect on Mg2+-dependent phosphoprotein formation. Taken together, these data indicate that Mg2+ stimulated Ca2+ and Sr2+ transport by increasing the Ca2+ (Sr2+)/ATP ratio.(ABSTRACT TRUNCATED AT 400 WORDS)
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Conformational changes of the Ca2+-ATPase as early events of Ca2+ release from sarcoplasmic reticulum. J Biol Chem 1985. [DOI: 10.1016/s0021-9258(17)36203-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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