Meg Lota Brown

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Courses

Scholarly Contributions

Books

• Brown, M. L. (2017). The Variorum Edition of the Poetry of John Donne. Indiana University Press.
• Brown, M. L. (2005). Women's Role's During the Renaissance. London: Greenwood Press.
• Brown, M. L. (1995). Donne and the Politics of Conscience in Early Modern England. Leiden, The Netherlands: E. J. Brill.

Chapters

• Brown, M. L., & McBride, K. (2013). "Women and Early Modern Education". In The Cultural History of Women, Vol. 3: The Renaissance(pp 143-163). London: Bloomsbury.
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  hardcover edition 2013; paperback issue 2016
• Brown, M. L. (2000). "Reputation and Rectitude in Christine de Pizan's Book of Three Virtues". In Au Champ des Escriptures(pp 449-461). Paris: Champion Press.
• Brown, M. L. (1993). Rachel Speght. In Seventeenth-Century British Non-Dramatic Poets(pp 246-249). Detroit: Gale.
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  Dictionary of Literary Biography, vol. 126
• Brown, M. L. (1991). "Interpretive Authority in Biathanatos". In Praise Disjoined: Changing Patterns of Salvation in Seventeenth-Century Literature(pp 151-163).
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  Seventeenth-Century Texts and Studies, vol. 2
• Brown, M. L. (1988). "'In that the world's contracted thus': Casuistical Politics in Donne's 'Sunne Rising'". In "The Muses Common-Weale": Poetry and Politics in the Seventeenth Century(pp 23-33). Columbia: University of Missouri Press.

Journals/Publications

• Brown, M., Fortk, E., & Brown, M. L. (0). [Inhaled corticosteroids and growth - a review]. Jornal de pediatria, 76(4).
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  OBJECTIVE: The aim of this review was to evaluate the medical literature in the last 10 years regarding the impact of the use of ICS on children and adolescents growth.METHODS: literature review.RESULTS: The use of ICS in childhood asthma in dosages appropriate to its severity does not seem to impair the adult height.CONCLUSIONS: The use of ICS in childhood asthma does not seem to impair growth. However, it is prudent to use the lowest possible dose necessary to achieve a good clinical control of asthma, as well as to monitor the growth of any child/adolescent receiving ICS.
• Brown, M. L., & McBride, K. (2009). "Etching into the Canon: Women Artists in Early Modern Europe". The International Journal of the Humanities, 7(2), 167-174.
• Brown, M. L. (2002). "Review of Sharon Cadman Seelig's Generating Texts: The Progeny of Seventeenth-Century Prose". Seventeenth-Century News, 60, 205-208.
• Brown, M. L. (2001). "Absorbing Difference in Donne's Malediction Forbidding Morning". The John Donne Journal, 20, 289-292.
• Brown, M. L. (2000). "Shakespeare and the Possibilities of Comedy: 'Much Virtue in If'". The Journal of By Design, 3.
• Brown, M., Keister, Z. O., DeNise, S. K., Armstrong, D. V., Ax, R. L., & Brown, M. L. (1999). Pregnancy outcomes in two commercial dairy herds following hormonal scheduling programs. Theriogenology, 51(8).
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  There are a number of options for hormonal management of post partum dairy cows; however, only a few studies have made direct comparisons of these programs in commercial herd settings. We compared reproductive management programs of 2 commercial dairy herds to evaluate the efficacy of prostaglandin-based treatment regimens on reproductive outcomes. Cows in Herd A were left untreated and served as the negative controls. Cows in Herd B were given PGF2alpha every 14 d until first insemination beginning 45 d post partum and served as the positive controls. Treatment 1 (Ovsynch), initiated randomly during the estrous cycle, consisted of sequential injections of GnRH, PGF2alpha, GnRH again and insemination 16 to 20 h later. Treatment 2 consisted of an Ovsynch protocol, as described above, which was begun 7 d post estrus (Ovsynch + 7). In Herd A, the number of days from parturition to conception (days open) for controls, for Ovsynch and for Ovsynch + 7 were 126, 112 and 102, respectively. In Herd B, respective days open were 102, 100 and 93 for controls, Ovsynch and Ovsynch + 7. Hormonal intervention reduced the number of days open in both herds.
• Brown, M., Moltke, S., Nevzorov, A. A., Sakai, N., Wallat, I., Job, C., Nakanishi, K., Heyn, M. P., & Brown, M. L. (1998). Chromophore orientation in bacteriorhodopsin determined from the angular dependence of deuterium nuclear magnetic resonance spectra of oriented purple membranes. Biochemistry, 37(34).
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  The orientation of prosthetic groups in membrane proteins is of considerable importance in understanding their functional role in energy conversion, signal transduction, and ion transport. In this work, the orientation of the retinylidene chromophore of bacteriorhodopsin (bR) was investigated using 2H NMR spectroscopy. Bacteriorhodopsin was regenerated with all-trans-retinal stereospecifically deuterated in one of the geminal methyl groups on C1 of the cyclohexene ring. A highly oriented sample, which is needed to obtain individual bond orientations from 2H NMR, was prepared by forming hydrated lamellar films of purple membranes on glass slides. A Monte Carlo method was developed to accurately simulate the 2H NMR line shape due to the distribution of bond angles and the orientational disorder of the membranes. The number of free parameters in the line shape simulation was reduced by independent measurements of the intrinsic line width (1.6 kHz from T2e experiments) and the effective quadrupolar coupling constant (38. 8-39.8 kHz from analysis of the line shape of a powder-type sample). The angle between the C1-(1R)-1-CD3 bond and the purple membrane normal was determined with high accuracy from the simultaneous analysis of a series of 2H NMR spectra recorded at different inclinations of the uniaxially oriented sample in the magnetic field at 20 and -50 degrees C. The value of 68.7 +/- 2.0 degrees in dark-adapted bR was used, together with the previously determined angle of the C5-CD3 bond, to calculate the possible orientations of the cyclohexene ring in the membrane. The solutions obtained from 2H NMR were then combined with additional constraints from linear dichroism and electron cryomicroscopy to obtain the allowed orientations of retinal in the noncentrosymmetric membrane structure. The combined data indicate that the methyl groups on the polyene chain point toward the cytoplasmic side of the membrane and the N-H bond of the Schiff base to the extracellular side, i.e., toward the side of proton release in the pump pathway.
• Brown, M. L. (1995). "Marriage As Bullfight in The Old Matador". The Journal of By Design, 1-3.
• Brown, M. L. (1994). "The Old Matador". Preview, 7.
• Brown, M., & Brown, M. L. (1994). Modulation of rhodopsin function by properties of the membrane bilayer. Chemistry and physics of lipids, 73(1-2).
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  A prevalent model for the function of rhodopsin centers on the metarhodopsin I (MI) to metarhodopsin II (MII) conformational transition as the triggering event for the visual process. Flash photolysis techniques enable one to determine the [MII]/[MI] ratio for rhodopsin in various recombinant membranes, and thus investigate the roles of the phospholipid head groups and the lipid acyl chains systematically. The results obtained to date clearly show that the pK for the acid-base MI-MII equilibrium of rhodopsin is modulated by the lipid environment. In bilayers of phosphatidylcholines the MI-MII equilibrium is shifted to the left; whereas in the native rod outer segment membranes it is shifted to the right, i.e., at neutral pH near physiological temperature. The lipid mixtures sufficient to yield full photochemical function of rhodopsin include a native-like head group composition, viz, comprising phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylserine (PS), in combination with polyunsaturated docosahexaenoic acid (DHA; 22:6 omega 3) chains. Yet such a native-like lipid mixture is not necessary for the MI-MII conformational transition of rhodopsin; one can substitute other lipid compositions having similar properties. The MI-MII transition is favored by relatively small head groups which produce a condensed bilayer surface, viz, a comparatively small interfacial area as in the case of PE, together with bulky acyl chains such as DHA which prefer a relatively large cross sectional area. The resulting force imbalance across the layer gives rise to a curvature elastic stress of the lipid/water interface, such that the lipid mixtures yielding native-like behavior form reverse hexagonal (HII) phases at slightly higher temperatures. A relatively unstable membrane is needed: lipids tending to form the lamellar phase do not support full native-like photochemical function of rhodopsin. Thus chemically specific properties of the various lipids are not required, but rather average or material properties of the entire assembly, which may involve the curvature free energy of the membrane-lipid water interface. These findings reveal that the membrane lipid bilayer has a direct influence on the energetics of the conformational states of rhodopsin in visual excitation.
• Brown, M., Fisher, L. A., & Brown, M. L. (1993). Neuropeptides and the autonomic nervous system. Psychotherapy and psychosomatics, 60(1).
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  Peptides are a class of intercellular messengers that are found in virtually every bodily organ. Evidence is reviewed here that peptides may function physiologically in brain pathways that coordinate and integrate whole-organism responses. The focus is on selected peptides that produce complementary neuropharmacological actions on behavior, endocrine secretions and autonomic nervous activity.
• Brown, M., Gibson, N. J., & Brown, M. L. (1993). Lipid headgroup and acyl chain composition modulate the MI-MII equilibrium of rhodopsin in recombinant membranes. Biochemistry, 32(9).
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  A current paradigm for visual function centers on the metarhodopsin I (MI) to metarhodopsin II (MII) conformational transition as the trigger for an intracellular enzyme cascade leading to excitation of the retinal rod. We investigated the influences of the membrane lipid composition on this key triggering event in visual signal transduction using flash photolysis techniques. Bovine rhodopsin was combined with various phospholipids to form membrane recombinants in which the lipid acyl chain composition was held constant at that of egg phosphatidylcholine (PC), while the identity of the lipid headgroups was varied. The ratio of MII/MI produced in these recombinants by an actinic flash at 28 degrees C was studied as a function of pH. The results were compared to the photochemical function observed for rhodopsin in native retinal rod outer segment (ROS) membranes, in total native ROS lipid recombinants, and in dimyristoylphosphatidylcholine (DMPC) recombinants. In membrane recombinants incorporating lipids derived from egg PC, as well as in the total ROS lipids control and the native ROS disk membranes, MI and MII were found to coexist in a pH-dependent, acid-base equilibrium on the millisecond time scale. The recombinants of rhodopsin with egg PC, either alone or in combination with egg PC-derived phosphatidylethanolamine (PE) or phosphatidylserine (PS), exhibited substantially reduced photochemical activity at pH 7.0. However, all recombinants comprising phospholipids with unsaturated acyl chains were capable of full native-like MII production at pH 5.0, confirming previous results [Gibson, N.J.. & Brown, M.F. (1990) Biochem. Biophys. Res. Commun. 169, 1028-1034]. It follows that energetic constraints on the MI and MII states imposed by egg PC-derived acyl chains can be offset by increased activity of H+ ions. The data reveal that the major effect of the membrane lipid composition is to alter the apparent pK for the MI-MII conformational equilibrium of rhodopsin [Gibson, N.J., & Brown, M.F. (1991) Biochem. Biophys. Res. Commun. 176, 915-921]. Recombinants containing only phosphocholine headgroups exhibited the lowest apparent pK values, whereas the presence of either 50 mol % PE or 15 mol % PS increased the apparent pK. The inability to obtain full native-like function in recombinants having egg PC-derived chains and a native-like headgroup composition indicates a significant role of the polyunsaturated docosahexaenoic acid (DHA) chains (22:6 omega 3) of the native retinal rod membrane lipids. Temperature studies of the MI-MII transition enabled an investigation of lipid influences on the thermodynamic parameters of a membrane protein conformational change linked directly to function.(ABSTRACT TRUNCATED AT 400 WORDS)
• Brown, M., Thurmond, R. L., Lindblom, G., & Brown, M. L. (1993). Curvature, order, and dynamics of lipid hexagonal phases studied by deuterium NMR spectroscopy. Biochemistry, 32(20).
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  Solid-state deuterium (2H) NMR spectroscopy enables one to study both equilibrium and dynamical properties of membrane constituents at the molecular level and can yield significant insights regarding the organization of non-bilayer lipid aggregates. We have investigated a representative unsaturated phosphatidylethanolamine, viz., 1-perdeuteriopalmitoyl-2-linoleoyl-sn-glycero- 3-phosphoethanolamine, PLPE-d31, in the lamellar, or L alpha, phase and the reversed hexagonal, or HII, phase. Phosphorus-31 (31P) NMR studies of PLPE-d31 in the HII phase revealed that the chemical shift anisotropy of the phosphoethanolamine head groups, delta sigma, was scaled by the expected geometrical factor of -1/2 relative to the lamellar state. However, we found the occurrence of a further reduction in the 2H NMR quadrupolar splittings, delta vQ, of the 2H-labeled palmitoyl acyl chain segments. These observations point toward the role of interfacial curvature with regard to properties of reverse hexagonal phase lipids, and indicate that the pivotal position or neutral surface of approximately constant area may lie near the glycerol or polar head group region. Variations in the acyl chain packing due to curvature of the aqueous interface yield significant differences in the segmental order profiles as determined by 2H NMR spectroscopy. The latter reflect the local orientational order of the acyl chains and can be used together with simple statistical theories to extract positional or structural information. Average projected acyl chain lengths and mean interfacial or cross-sectional areas for PLPE-d31 in the different phases have been calculated. In addition, we describe a new means of estimating the radius of curvature of HII phase lipid aggregates utilizing 2H NMR spectroscopy, which is based on the difference between the lamellar and hexagonal phase order profiles. Here the radius of curvature, Rc, is defined as the distance from the center of the water core to the lipid/water interface, near the carbonyl segments of the acyl chains, giving Rc = 25.4-28.1 A for PLPE-d31 in the HII phase at 60 degrees C. This value is in good agreement with previous X-ray diffraction studies of 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE). Alternatively, the data yield for the radius of the central water core that Rw = 17.8-20.5 A at 60 degrees C. The differences in geometry also lead to higher quadrupolar echo relaxation rates (R2e) for the lipid acyl segments closest to the aqueous interface in the HII versus the L alpha phase.(ABSTRACT TRUNCATED AT 400 WORDS)
• Brown, M. L. (1992). "'Though it be not according to the law': Donne's Politics and the Sermon on Esther". The John Donne Journal, XI, 71-84.
• Brown, M. L. (1991). "The Politics of Conscience in Reformation England". Renaissance and Reformation / Renaissance et Reforme, XXVII, 101-114.
• Brown, M., Barry, J. A., Trouard, T. P., Salmon, A., & Brown, M. L. (1991). Low-temperature 2H NMR spectroscopy of phospholipid bilayers containing docosahexaenoyl (22:6 omega 3) chains. Biochemistry, 30(34).
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  Polyunsaturated fatty acids are widely distributed components of biological membranes and are believed to be involved in many biological functions. However, the mechanisms by which they act on a molecular level are not understood. To further investigate the unique properties of omega 3 polyunsaturated phospholipid bilayers, deuterium nuclear magnetic resonance (2H NMR) studies have been made of the liquid-crystalline (L alpha) and gel phases of a homologous series of mixed-chain phosphatidylcholines containing docosahexaenoic acid: (per-2H-n:0)(22:6)PC, where n = 12, 14, 16, and 18. The moments of the 2H NMR lineshapes have been evaluated, and from these the warming and cooling main phase transition temperatures were determined. The transition temperatures of the mixed-chain series were found to be significantly lower than those of the corresponding lipids in the disaturated series, di(per-2H-n:0)PC, with hystereses ranging from 2 to 14 degrees C. Distinct effects of the docosahexaenoyl chain on bilayer order were found, though these effects varied across the mixed-chain series. In evaluating the moment data, an empirical method for normalizing the moments with respect to differences in temperature was applied, in addition to using the reduced temperature method. For the systems studied here, the method of normalization had no significant effect on the interpretation of the moment data.
• Brown, M., Fisher, L., Rivier, C., Rivier, J., & Brown, M. L. (1991). Differential antagonist activity of alpha-helical corticotropin-releasing factor9-41 in three bioassay systems. Endocrinology, 129(3).
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  Studies were performed in conscious unrestrained rats to compare the ability of the CRF receptor antagonist, alpha-helical CRF9-41, to inhibit the actions of CRF in three in vivo bioassay systems. When both peptides were administered intracerebroventricularly, an antagonist:agonist ratio between 6:1-12:1 was required to abolish CRF-induced elevations of plasma catecholamine levels. When both peptides were administered iv, CRF-induced hypotension and tachycardia were completely prevented by an antagonist:agonist ratio of 6:1, whereas total blockade of CRF-induced elevations of plasma ACTH and beta-endorphin levels required an antagonist:agonist ratio of 3000:1. These results demonstrate marked differences in the ability of alpha-helical CRF9-41 to antagonize various biological actions of CRF and support the existence of multiple CRF receptor subtypes.
• Brown, M., Gibson, N. J., & Brown, M. L. (1991). Membrane lipid influences on the energetics of the metarhodopsin I and metarhodopsin II conformational states of rhodopsin probed by flash photolysis. Photochemistry and photobiology, 54(6).
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  We have investigated the relationship between rhodopsin photochemical function and the retinal rod outer segment (ROS) disk membrane lipid composition using flash photolysis techniques. Bovine rhodopsin was combined with various phospholipids to form recombinant membrane vesicles, in which the lipid acyl chain composition was maintained at that of egg phosphatidylcholine (PC), while the nature of the headgroups was varied. The ratio of metarhodopsin II (MII)/metarhodopsin I (MI) in these recombinants produced by an actinic flash was investigated as a function of pH, and compared with the photochemical activity observed for rhodopsin in native ROS membranes and dimyristoylphosphatidylcholine recombinants. In recombinants made with lipids derived from egg PC, as well as in native ROS membranes, MI and MII were found to be present in a pH-dependent, acid-base equilibrium on the millisecond timescale. The recombinants made with phospholipids containing unsaturated acyl chains were capable of full native-like MII production, but each demonstrated a titration curve with a different pK. In addition, some of the recombinants exhibited apparent deviations from the Henderson-Hasselbalch curve shape. The presence of either phosphatidylethanolamine (PE) or phosphatidylserine (PS) headgroups appeared to increase the amount of MII produced. This may result from alteration of the curvature free energy, in the case of PE, and from the influence of the membrane surface potential in the case of PS. An investigation of the effects of temperature on the MI-MII transition in native ROS membranes and the recombinants was also carried out.(ABSTRACT TRUNCATED AT 250 WORDS)
• Brown, M., Gibson, N. J., & Brown, M. L. (1991). Role of phosphatidylserine in the MI-MII equilibrium of rhodopsin. Biochemical and biophysical research communications, 176(2).
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  Bovine rhodopsin was recombined with various phospholipids in which the lipid acyl chain composition was held constant at that of egg phosphatidylcholine (PC), while the identity of the headgroups was varied. The ratio of MII/MI produced in the recombinant membrane vesicles by an actinic flash was studied as a function of pH, and compared to the photochemical activity observed for rhodopsin in native ROS membranes. MI and MII were found to coexist in a pH-dependent, acid-base equilibrium on the millisecond timescale. Recombinants made with phospholipids containing unsaturated acyl chains were capable of full native-like MII production, but demonstrated titration curves with different pK values. The presence of phosphoethanolamine or phosphoserine headgroups increased the amount of MII produced. In the case of phosphatidylserine this may result from alteration of the membrane surface potential, leading to an increase in the local H+ activity. The results indicate that the Gibbs free energies of the MI and MII conformational states are influenced by the membrane bilayer environment, suggesting a possible role of lipids in visual excitation.
• Brown, M., Poore, M. H., Moore, J. A., Swingle, R. S., Eck, T. P., & Brown, M. L. (1991). Wheat straw or alfalfa hay in diets with 30% neutral detergent fiber for lactating Holstein cows. Journal of dairy science, 74(9).
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  Twenty-four Holstein cows near peak lactation were fed diets formulated to contain 30% NDF with forage NDF from chopped wheat straw or chopped alfalfa hay in proportions of 0:3, 1:2, 2:1, and 3:0 in an 8-wk trial to evaluate effects of fiber source on lactational performance. Concentrate was based on highly degradable carbohydrate in steam-flaked sorghum grain. Forage to concentrate ratio decreased from 49:51 to 28:72 when straw was substituted for alfalfa hay. Milk yield (38.4 kg/d) and DMI (23.1 kg/d) were not influenced by forage source. Milk fat percentage decreased and milk protein percentage increased linearly with increasing straw. Yields of 3.5% FCM and fat showed linear and quadratic responses, because they appeared to be reduced only on the 0:3 diet, and protein yield showed a quadratic response and was highest for the 1:2 diet. Digestibility of NDF averaged 43.5, 45.4, 40.7, and 31.2%, and acetate to propionate ratio was 3.0, 2.4, 2.2, and 1.9 with increasing dietary straw. Passage rates were not influenced by diet and averaged 9.3, 7.6, 6.1, and 4.7%/h for fluid, grain, alfalfa hay, and wheat straw, respectively. It is suggested that the ratio of forage NDF to ruminally degradable starch be maintained greater than or equal to 1:1 when diets based on low quality forage are fed to cows in early lactation.
• Brown, M., Rajamoorthi, K., & Brown, M. L. (1991). Bilayers of arachidonic acid containing phospholipids studied by 2H and 31P NMR spectroscopy. Biochemistry, 30(17).
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  The configurational properties and dynamics of the arachidonic acyl chains of phospholipid bilayers have been investigated for the first time by solid-state 2H NMR techniques, with the goal of achieving a better understanding of the biological roles of polyunsaturated phospholipids. Vinyl perdeuterated arachidonic acid (20:4 delta 5,8,11,14-d8) was prepared from eicosatetraynoic acid (ETYA) and was esterified with 1-palmitoyl-sn-glycero-3-phosphocholine to yield 1-palmitoyl-2-vinylperdeuterioarachidonoyl-sn-glycero-3-phosphocho line [(16:0)(20:4-d8)PC]. 31P NMR spectra of aqueous dispersions of (16:0)(20:4-d8)PC as well as 1-perdeuteriopalmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine [(per-2H-16:0)(20:4)PC] were characteristic of the lamellar liquid-crystalline state. The dispersions had similar 31P chemical shift anisotropies, with little apparent motional averaging of the lineshapes due to macroscopic reorientation of liposomes or lateral diffusion of phospholipids about their curved surfaces. Comparison to other phosphatidylcholines indicated that both samples comprised the fully hydrated L alpha phase plus excess water. However, the dispersion of (16:0)(20:4-d8)PC yielded relatively narrow powder-type 2H NMR spectra, compared to (per-2H-16:0)(20:4)PC in the liquid-crystalline state. The differences in the 2H NMR powder patterns thus reflect differences in the configurational properties of the polyunsaturated sn-2 arachidonic acyl chain compared to the saturated sn-1 palmitic chain. When the powder-type 2H NMR spectra of the (16:0)(20:4-d8)PC bilayer were dePaked (theta = 0 degrees), they showed three kinds of deuterons upon integration: one with a large splitting (approximately 25-35 kHz), two with intermediate splittings (approximately 10-15 kHz), and the remainder with smaller splittings (approximately 0.3-5 kHz).(ABSTRACT TRUNCATED AT 250 WORDS)
• Brown, M., Thurmond, R. L., Dodd, S. W., & Brown, M. L. (1991). Molecular areas of phospholipids as determined by 2H NMR spectroscopy. Comparison of phosphatidylethanolamines and phosphatidylcholines. Biophysical journal, 59(1).
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  The role of lipid diversity in biomembranes is one of the major unsolved problems in biochemistry. One parameter of possible importance is the mean cross-sectional area occupied per lipid molecule, which may be related to formation of nonbilayer structures and membrane protein function. We have used 2H NMR spectroscopy to compare the properties of 1,2-diperdeuteriopalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE-d62) and 1,2-diperdeuteriopalmitoyl-sn-glycero-3-phosphocholine (DPPC-d62) in the L alpha phase. We find that DPPE has greater segmental order than DPPC, and that this increase in order is related to the smaller area per acyl chain found for DPPE. Values of the mean cross-sectional chain area are calculated using a simple diamond lattice model for the acyl chain configurational statistics, together with dilatometry data. The results obtained for the mean area per molecule are comparable with those from low angle x-ray diffraction studies.
• Brown, M., Thurmond, R. L., Lindblom, G., & Brown, M. L. (1991). Effect of bile salts on monolayer curvature of a phosphatidylethanolamine/water model membrane system. Biophysical journal, 60(3).
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  A partial phase diagram of the ternary system dioleoylphosphatidylethanolamine (DOPE)/sodium cholate/water has been determined using 31P Nuclear Magnetic Resonance (NMR) spectroscopy. In the absence of cholate, it is well known that the DOPE/water system forms a reversed hexagonal (HII) phase. We have found that addition of even small amounts of cholate to the DOPE/water system leads to a transition to a lamellar (L alpha) phase. At higher cholate concentrations, a cubic (I) phase (low water content) or a micellar solution (L1) phase (high water content) is present. Thus, cholate molecules have a strong tendency to alter the lipid monolayer curvature. Increasing the concentration of cholate changes the curvature of DOPE from negative (HII phase), through zero (L alpha phase), and finally to a phase of positive curvature (micellar solution). This observation can be rationalized in terms of the molecular structure of cholate, which is amphipathic and has one hydrophobic and one hydrophilic side of the steroid ring system. The cholate molecules have a tendency to lie flat on the lipid aggregate surface, thereby increasing the effective interfacial area of the polar head groups, and altering the curvature free energy of the system.
• Brown, M., Gibson, N. J., & Brown, M. L. (1990). Influence of pH on the MI-MII equilibrium of rhodopsin in recombinant membranes. Biochemical and biophysical research communications, 169(3).
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  Rhodopsin in native rod membranes and incorporated into egg phosphatidylcholine (egg PC) vesicles was studied at pH 5 and 7 at 28 degrees C. Rhodopsin function, as monitored by the formation of metarhodopsin II (MII) from metarhodopsin I (MI) following an actinic flash, was found to be largely blocked in egg PC vesicles at pH 7. When the pH was lowered to 5, however, rhodopsin showed essentially equal activity in both native and egg PC membranes. This activity exceeded that found for rhodopsin in native membranes at pH 7. Phospholipid composition is thus shown to directly affect the MI in equilibrium MII equilibrium, which in turn is linked to visual function.
• Brown, M., Jansson, M., Thurmond, R. L., Trouard, T. P., & Brown, M. L. (1990). Magnetic alignment and orientational order of dipalmitoylphosphatidylcholine bilayers containing palmitoyllysophosphatidylcholine. Chemistry and physics of lipids, 54(3-4).
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  Mixed bilayers of 1-palmitoyl-sn-glycero-3-phosphocholine (palmitoyllysophosphatidylcholine; PaLPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (dipalmitoyl phosphatidylcholine; DPPC) have been investigated by 2H-NMR and 31P-NMR spectroscopy. Binary phospholipid mixtures were studied in which the acyl chains of one or the other component were perdeuterated. At temperatures below the main order-disorder phase transition, the mixed PaLPC/DPPC bilayers appear to coexist with PaLPC micelles. The micelles disappear at temperatures above the phase transition, where mixed bilayers in the liquid-crystalline state are formed. The orientational order of the alkyl chains of the PaLPC component is essentially identical to that of the DPPC component in the mixed bilayers, both in the low temperature and liquid-crystalline phases. However, the presence of PaLPC perturbs the segmental ordering of DPPC as compared to the pure system. The order is increased in the low-temperature phase, where effective diffusion of the chains about their long axes occurs, but is decreased in the liquid-crystalline phase compared to pure DPPC bilayers. The mixed liquid-crystalline bilayers orient preferentially with their director axes perpendicular to the magnetic field. This alignment is easily observed in 31P- and 2H-NMR spectra, where the intensity of the perpendicular edges of the lineshapes is pronounced. One possible explanation of the magnetic alignment involves alteration of the curvature free energy of the DPPC bilayer due to incorporation of PaLPC in the mixed membranes.
• Brown, M., Thurmond, R. L., Lindblom, G., & Brown, M. L. (1990). Influences of membrane curvature in lipid hexagonal phases studied by deuterium NMR spectroscopy. Biochemical and biophysical research communications, 173(3).
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  The presence of reversed hexagonal phase, HII, favoring lipids in membranes has been proposed to be significant in various biological processes. Therefore an understanding of the HII phase and the transition from the lamellar to hexagonal phase is of importance. We have applied deuterium NMR spectroscopy to study the bilayer and reversed hexagonal phases of 1-perdeuteriopalmitoyl-2-linoleoyl-sn-glycero-3-phosphoethanolamin e. The difference in packing between the HII and L alpha phases leads to smaller segmental order parameters in the former case. Since the order profiles are sensitive to the geometry of the aggregates, they can be used to extract structural information about the phases. We present a new means of calculating the radius of curvature, R1, for the HII phase from 2H NMR data. This method gives a value of R1 = 18.1 A, which is in agreement with current understanding of the structure of the HII phase and with x-ray diffraction data.
• Brown, M., Whiting, F. M., Lough, O. G., & Brown, M. L. (1987). Occurrence of DDE in dairy feeds in the Arizona milk shed. Bulletin of environmental contamination and toxicology, 39(4).

Presentations

• Brown, M. L. (2009, Summer). "Etching into the Canon: Women Artists in Early Modern Europe". Seventh International Conference on New Directions in the Humanities. Beijing, China.
• Brown, M. L. (2017, April). “National Best Practices in Micro-credentialing and the UA Pilot”. UA Graduate Council. University of Arizona: UA Graduate Council.
• Brown, M. L. (2017, March). “Graduate Mentoring and Individual Development Plans”. UA Graduate College Enrollment Management Series. University of Arizona: UA Graduate College.
• Brown, M. L. (2017, November). “Council of Graduate Schools National Initiatives in Support of Multiple Career Pathways for PhDs”. Graduate College Enrollement Management Series. University of Arizona: UA Graduate College.
• Brown, M. L. (2017, November). “National Best Practices in Micro-credentialing and the UA Pilot”. Provost's Deans Council. University of Arizona.
• Brown, M. L. (2017, November). “Supporting Graduate Students in Multiple Career Pathways”. UA Graduate Council. University of Arizona: UA Graduate Council.
• Brown, M. L. (2016, Spring). "Femininity and Other Perils in Renaissance Culture". Tucson Literary ClubTucson Literary Club.
• Brown, M. L. (2016, Spring). "Shakespeare and Cervantes". Cervantes Anniversary Commemoration. University of Arizona Poetry Center.
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  interdisciplinary event
• Brown, M. L. (2016, Spring). "Shakespeare's Women". Folger Shakespeare Library's First Folio exhibition. University of Arizona Special Collections.
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  invited keynote lecture
• Brown, M. L. (2014, Fall). "Muse and Menace in Early Modern Literature". Harvard ClubHarvard Club.
• Brown, M. L. (2012, Summer). "Art, Gender, and Legitimacy: Early Modern Women Writers in Europe". Seventh International Conference on the Arts in Society. Liverpool, England.
• Brown, M. L. (2011, Spring). "Bodies in Labor: Female Prostitutes, Healers, and Midwives in Early Modern Europe". South Central Renaissance Conference. St. Louis.
• Brown, M. L. (2011, Spring). "Early Modern Women Forging the Visual Canon". CSU Research Conference.
• Brown, M. L. (2009, Spring). "Genre, Gender, and Engraving in Early Modern Europe". South Central Renaissance Conferece.
• Brown, M. L. (2006, Fall). Handel's Oratorio of Milton's 'L'Allegro' and 'Il Penseroso'". lecture to the UA Music DepartmentUniversity of Arizona.
• Brown, M. L. (2005, Fall). "Women in Early Modern Europe". invited lectureUniversity of Arizona.
• Brown, M. L. (2005, Spring). "Early Modern English Culture". invited lecture. Rincon High School.
• Brown, M. L. (2005, Spring). "Shakespeare and Early Modern Women". invited lecture. St. Gregory School.
• Brown, M. L. (2004, Spring). "Donne and the Holy Sonnets". invited lecture for UA Music Department. University of Arizona: University of Arizona Music Department.
• Brown, M. L. (2003, Fall). "Disorder and the Renaissance". invited lecture at St. Gregory School. St. Gregory School.
• Brown, M. L. (2002, Summer). "Milton's 'fancies fond': Femininity, Poetry, and Other Perils". invited lecture at the University of Groningen. University of Groningen, The Netherlands: University of Groningen.
• Brown, M. L. (2001, Summer). "Figuring Pleasure in the Poetry of Behn, Herrick, Jonson, and Suckling". invited lecture at the University of Amsterdam. University of Amsterdam (Universiteit van Amsterdam), The Netherlands: University of Amsterdam.
• Brown, M. L. (2001, Summer). "The Ideology of the Country House Poem in Seventeenth-Century England". invited lecture at St. Catherine's College, Cambridge University. St. Catherine's College, Cambridge University, England: St. Catherine's College, Cambridge University.
• Brown, M. L. (1999, Fall). "Absorbing Difference in Donne's Malediction Forbidding Morning". John Donne Society Conference.
• Brown, M. L. (1998, Summer). "Ambition and Counsel in Christine de Pizan's The Treasure of the City of Ladies". International Pizan Conference. Lausanne, Switzerland.
• Brown, M. L. (1997, Spring). "Curious Reading". Modern Language Association Conference. Toronto, Canada: MLA.
• Brown, M. L. (1995, Spring). "Sexuality and Violence in Renaissance Literature". invited lecture at Faculty Honors Forum. University of Arizona: University of Arizona.
• Brown, M. L. (1995, Summer). "'An affliction which defeats all Magistracy': Authorizing Interpretation". Literature and History Conference. University of Reading, England: University of Reading.
• Brown, M. L. (1992, Summer). "Donne and the Politics of Interpretation: Conscience and Power in Pseudo-Martyr". Literature and History Conference. University of Reading, England: University of Reading.
• Brown, M. L. (1990, Spring). "Reformation Politics of Interpretation". 21st Annual Interdisciplinary Committee for Advancement of Early Studies.
• Brown, M. L. (1990, Summer). "The Politics of Conscience: Transformations of Continental Casuistry in the English Renaissance". annual conference. University of Glasgow, Scotland: University of Glasgow.
• Brown, M. L. (1989, Spring). "Case Divinity and Reform in Seventeenth-Century England". 24th International Congress on Medieval Studies.
• Brown, M. L. (1989, Spring). "Conscience and Contention: Practical Theology in the Seventeenth Century". UAMARRCUAMARRC.
• Brown, M. L. (1988, Fall). "Shakespeare and Casuistry". invited presentation at the University of Montana. University of Montana: University of Montana.
• Brown, M. L. (1988, Spring). "'Nothing without perplexities': 'A Valediction: forbidding mourning'". invited lecture at Oakland University. Oakland University: Oakland University.
• Brown, M. L. (1988, Spring). "Doubt and Assurance in 'A Valediction: forbidding mourning'". Donne Society Conference.
• Brown, M. L. (1988, Spring). "Perplexity and Definition in 'The Canonization'". invited presentation at Union College. Union College: Union College.
• Brown, M. L. (1987, Fall). "Casuistry and Controversy in Seventeenth-Century England". Pacific Coast Conference on British Studies. Stanford University.
• Brown, M. L. (1987, Spring). "Perplexity & Parody in Donne's Anti-aubade". Medieval Association of the Midwest.
• Brown, M. L. (1987, Spring). "Problems of Reason & Language in Donne's Paradoxes and Essays". 22nd International Congress on Medieval Studies.
• Brown, M. L. (1986, Fall). "Casuistical Methodology in Donne's Pseudo-Martyr". John Donne Society Conference.
• Brown, M. L. (1986, Fall). "In that the world's contracted thus': Casuistical Politics in Donne's 'Sunne Rising'". University of Michigan-Dearborn Renaissance Conference.
• Brown, M. L. (1986, Spring). "'Moral divinity becomes us all': Donne's Sermon on Esther 4:16". South Central Renaissance Conference.
• Brown, M. L. (1985, Spring). "John Donne's Biathanatos: Moral Theology and Judgment". Le Moyne Forum on Religion and Literature.
• Brown, M. L. (1985, Spring). "The Sovereignty of Mutuality in the Wife of Bath's Prologue and Tale". Rocky Mountain Medieval and Renaissance Association Conference.

Others

• Brown, M., Erdoes, L. S., & Brown, M. L. (1995, Jul). Ruptured ulnar artery pseudoaneurysm. Annals of vascular surgery.
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  Ulnar artery aneurysms and pseudoaneurysms are rare lesions that usually occur distal to the wrist and cause symptoms as a result of embolization and not rupture. An elderly woman presented with acute rupture of an ulnar artery pseudoaneurysm proximal to the wrist, which caused severe neurologic compromise as a result of bleeding into Guyon's canal and the carpal tunnel. The patient had a remote wrist fracture resulting in a deformity that allowed the ulnar head to be in proximity to the ulnar artery. Rupture of the volar capsule with chronic abrasion of the artery eventually led to pseudoaneurysm formation and subsequent rupture. Emergency operative treatment with excision of the pseudoaneurysm, ulnar artery ligation, and repair of the volar capsule resulted in complete neurologic recovery without vascular compromise. This case is unique because of the proximal location of the pseudoaneurysm and the presentation with rupture. The anatomy, pathogenesis, and treatment options are discussed. Excision of the pseudoaneurysm with repair of the torn volar capsule is recommended to avoid recurrent problems. Vascular reconstruction is needed in cases where radial arterial flow is inadequate.