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Introduction: Thyroid storm (TS) is a rare, but critical illness that can cause multiorgan failure and carries a high risk of mortality. We describe a case of refractory TS successfully treated with SPAD. Case: A 48 y/o lady was evaluated for sustained ventricular tachycardia (SVT) in the setting of newly diagnosed thyroid storm. She received a left ventricular assist device (LVAD) 4 years ago for cardiomyopathy (EF< 20%). Exam: SVT and florid CHF. Biochemical evaluation following amiodarone infusion for 18 hours: TSH < 0.05 (0.4 - 4 UIU/ml), FT4 7.87(0.76-1.46ng/dl), TT3 181 (60-180 ng/dl). TPO, TRAB and TSI antibodies were negative. Thyroid sonogram showed heterogeneous normal sized gland, no nodules or hyper vascularity. She received methimazole (MMI) 60 mg orally twice daily, Lugol’s iodine 10 drops orally three times daily and hydrocortisone 100mg intravenously 3 times daily. Beta-blockers were deferred due to cardiogenic shock. Amiodarone (400 mg orally twice daily)) was continued for ongoing episodes of SVT. She developed shock liver limiting the continuation of maximum doses of MMI. Continuous veno-venous hemofiltration (CVVH) was initiated for anuric renal failure. She required ventilator and pressor support on day 7 (D7) of hospitalization as urgent preparations were being made for LVAD exchange (given LVAD malfunction). TFts obtained on D7 showed a suboptimal response to maximal therapy: FT4 3.86, TT3 146. She underwent emergent SPAD using modified CVVH with dialysate containing 4% human albumin for 12 hrs. pre-operatively. It led to a fall in the FT4 to 1.71 and TT3 to 90. She received a new LVAD without further episodes of SVT. TFTs subsequent to 8 additional sessions of SPAD (as a bridge to definitive thyroidectomy) were as follows: FT4 1.56, TT3 76, thereby allowing for a dose reduction in MMI. Thyroidectomy was considered but deferred since the family opted for comfort measures when the patient developed cardiac tamponade Conclusions: TS can be recalcitrant to therapy with MMI, beta blockade, cold iodine and steroids. Adjunct therapy such as lithium, cholestyramine, and plasmapheresis, in addition to conventional therapy may have limited benefit, and comes with potential side effects. SPAD offers a safe and effective therapeutic alternative for refractory TS that can be performed continuously for a sustained response. In our case, with SPAD, thyroid hormones dropped to permissible levels, thus allowing for successful completion of emergent high risk cardiac surgery. Additionally, SPAD may provide a window for definitive surgical intervention and should be considered in refractory TS.

In this work, we use Langmuir monolayers of dipalmitoyl phosphatidylcholine (DPPC) as model systems to enhance the understanding of specific anion effects in physicochemical and biological systems. The 298 K isotherms (equation of state, EOS) of DPPC over solutions of a range of sodium salts depend strongly on the type and concentration of the salt in the subphase. We focus in particular on the liquid expanded phase region of the DPPC EOS and assume that the deviation of the isotherms over electrolyte solutions from that over pure water is due entirely to the charging of the lipid monolayer by the ions. We then examine the ability of a range of phenomenological continuum models to explain the pressure increase in the presence of electrolytes. The important finding is that insoluble lipid monolayers allow the discrimination between possible modes of ion-lipid interaction. Chemical binding models, simple or modified, cannot fit the range of data presented in this work. Both dispersion interaction and partitioning models fit most of the experimental isotherms and provide unique values for dispersion coefficients or ionic partitioning constants, respectively, even though the nature of these models is completely different (the former concentrates on the potential of mean force that acts on an ion in the double layer, while the latter concentrates on the treatment of interactions at the interface). Surprisingly, the respective fitting parameters are very highly correlated, reflecting, we believe, the effect of ion size on ionic properties and interactions. With sodium fluoride (NaF) as the subphase electrolyte, it is demonstrated that sodium exhibits a weak complexation-type interaction with the zwitterionic lipids. The simple dispersion and partitioning models cannot account for the NaF results, highlighting the need for more complex salt-lipid interaction models that account both for sodium binding and anion partitioning. This realization sets the stage for the companion paper. © 2009 American Chemical Society. 113 5 1447 1459 Cited By :43

In the preceding paper of this series [Leontidis, E. Aroti, A. Belloni, L. J. Phys. Chem. B 2009, 113, 1447], we considered and modeled the increase of the surface pressure of dipalmitoyl phosphatidylcholine (DPPC) monolayers over electrolyte solutions of various monovalent sodium salts. The experimental results for salts with large, less hydrophilic anions can be successfully described by models treating ionic specificity either as specific partitioning in the interfacial lipid layer or as a result of ion-lipid dispersion interactions. However, the results for salts with more hydrophilic anions, such as chloride and fluoride, cannot be fitted by any of these models, while they clearly demonstrate the existence of a specific sodium-DPPC interaction. In the present paper, we first prove that the experimental results for sodium fluoride (NaF) can be fitted by a model that is based on simultaneous complexation of sodium ions with up to three lipid molecules, as suggested by recent molecular dynamics simulations. We then return to the experimental results of sodium salts with more hydrophobic anions, treated in the preceding paper, and prove that these can be fitted equally well with a complex model, which accounts for both sodium complexation with the lipid head groups and anion partitioning within the lipid monolayers. The partitioning parameters obtained from this more complete model correlate well with several measures of ion specificity, such as ionic volume, von Hippel chromatographic parameters, or viscosity B-coefficients. A model for these partitioning chemical potentials is created based on the competition of cavity and ion hydration terms. The model leads to an excellent correlation of the partitioning chemical potentials with a function of the ionic radius, suggesting that specific anion effects on this lipid model system are mostly a matter of ionic size. Two notable exceptions from this correlation are thiocyanate and acetate ions, the charge distribution of which is not spherically symmetric, so that they are expected to have orientational-dependent interactions with the water-lipid interface. The implications of the present results on ion specificity in general are discussed. © 2009 American Chemical Society. 113 5 1460 1467 Cited By :43

Alcoholism is one of the most common psychosocial disorders, affecting approximately 10% of the general population. The impact of alcoholism on the care of patients with other medical illnesses has not been addressed in many of these populations, including patients with end-stage renal disease (ESRD) undergoing hemodialysis. We set out to determine the prevalence of alcoholism in an urban hemodialysis population and ascertain whether alcoholism had an effect on compliance in this population. One hundred sixty-three urban hemodialysis patients were screened using the Michigan Alcoholism Screening Test (MAST), a 25-item questionnaire that has been validated in multiple trials. Forty-five patients (27.6%) scored 5 or greater on the MAST. The MAST-positive subjects were younger (age, 55 +/- 15 years versus 64 +/- 13 years) and tended to be men (58% versus 43%). There was no significant difference in the incidence of diabetic kidney disease; however, there were significantly more human immunodeficiency virus (HIV)-positive patients in the MAST-positive group. The dietary compliance measures of predialysis potassium or phosphorus levels did not differ between the two groups. A trend toward lower serum albumin level was evident in the men in the MAST-positive group (3.75 +/- 0.57 versus 3.91 +/- 0.30 g/dL; P = 0.0212). In conclusion, there is a high prevalence of alcoholism in the urban dialysis population. Alcoholic patients with ESRD are younger and tend to be men. HIV-positive patients with ESRD have a high prevalence of concomitant alcoholism. Compliance indicators of predialysis potassium and phosphorus levels are not affected. However, nutritional status, measured by serum albumin level, tends to be poorer in the alcoholic group.

Thiocyanate (SCN-) is a highly chaotropic anion of considerable biological significance, which interacts quite strongly with lipid interfaces. In most cases it is not exactly known if this interaction involves direct binding to lipid groups, or some type of indirect association or partitioning. Since thiocyanate is a linear ion, with a considerable dipole moment and nonspherical polarizability tensor, one should also consider its capability to adopt different or preferential orientations at lipid interfaces. In the present work, the interaction of thiocyanate anions with zwitterionic phospholipid monolayers in the liquid expanded (LE) phase is examined using surface pressure-area per molecule (π-AL) isotherms and vibrational sum frequency generation (VSFG) spectroscopy. Both dipalmitoyl phosphatidylcholine (DPPC) and dimyristoyl phosphatidylethanolamine (DMPE) lipids, which form stable monolayers, have been used in this investigation, since their headgroups may be expected to interact with the electrolyte solution in different ways. The π-?L isotherms of both lipids indicate a strong expansion of the monolayers when in contact with SCN- solutions. From the C-H stretch region of the VSFG spectra it can be deduced that the presence of the anion perturbs the conformation of the lipid chains significantly. The interfacial water structure is also perturbed in a complex way. Two distinct thiocyanate populations are detected in the CN stretch spectral region, proving that SCN- associates with zwitterionic phospholipids. Although this is a preliminary investigation of this complex system and more work is necessary to clarify certain points made in the discussion, a potential identification of the two SCN- populations and a molecular-level explanation for the observed effects of the SCN- on the VSFG spectra of the lipids is provided. © 2009 American Chemical Society. 113 44 14816 14823 Cited By :24

Aiming to improve understanding of the mechanisms behind specific anion effects in biological systems we have studied the effects of sodium salts of simple monovalent anions belonging to the Hofmeister series on the bilayers of the zwitterionic lipid 1,2-dipalmitoyl-sn-glycero-3-phosphocholine using small-angle x-ray scattering and the osmotic stress technique. NaCl, NaBr, NaNO3, NaI, and NaSCN were used in this investigation. The electrolytes were found to swell the bilayers and to increase the area per lipid headgroup at each value of the osmotic pressure, suggesting the association of anions with the bilayer-lipid interfaces. The effects follow the Hofmeister series with SCN- inducing the most pronounced changes. "Ion competition" experiments with mixed NaI/NaCl solutions at total salinity 0.1 and 0.5 M revealed that the effect of ions on the lipid equation-of-state is roughly linear at low concentrations, but strongly nonlinear at high concentrations. The experimental results are fitted in a companion article to provide "binding or "partitioning" constants of anions in the lipid bilayers. © 2007 by the Biophysical Society. 93 5 1580 1590 Cited By :67

This work is a review of the effect of different monovalent anions (belonging to the Hofmeister series) on a single model amphiphile, phosphatidylcholine molecules in contact with water, in three different geometries, Langmuir monolayers, bilayers and micelles, which differ by area per molecule and radius of curvature. The zwitterionic lipids DPPC (1,2-dipalmitoyl-phosphatidylcholine) and DPC (Dodecylphosphocholine) have been used to form the three geometries. The salt solutions used were NaCl, NaBr, NaNO3, NaI, NaBF4, NaClO4 and NaSCN. Various interfacial and bulk experimental techniques were used in order to study the effect of the anions on the amphiphiles in the three geometries. The interfacial techniques used were surface pressure-area isotherms, Brewster angle microscopy (BAM), Grazing incidence X-ray diffraction (GIXD), infrared reflection absorption spectroscopy (IRRAS). The bulk sensitive techniques used were small-angle X-ray scattering (SAXS), osmotic stress (OS) and light scattering. The experimental results obtained from the three model systems indicate that the interfaces become charged through lipid-ion association. The results were fitted with appropriate theoretical models to provide "binding" or "partitioning" constants of anions in the headgroup region of the lipid molecules. The theoretical analysis strongly suggests that the anions do not associate with the lipid molecules through a local chemical reaction, but rather they partition inside the disordered lipid interfaces. © 2007 Elsevier B.V. All rights reserved. 303 1-2 144 158 Cited By :36

The three main currently proposed approaches for understanding specific ion effects are briefly described. In some experimentally well defined and simplified situations, one can decouple ion specificity effects from all others. Small globular micelles in water/salt mixtures are one of the simple situations where specific ion effects can be distinguished: 'hydrophobic ions' introduced by Hofmeister in the late 19th century, also called 'structure breaking' or 'salting in' ions, which are similar to 'soft ions' in the classification introduced by Pearson, are more strongly adsorbed on the micellar surface than predicted by electrostatics alone. Hence, lateral repulsions between surfactants are increased, resulting in a measurable and calculable decrease of micelle size when adsorbing anions such as bromide replace non-adsorbing anions such as chloride. © 2004 Elsevier Ltd. All rights reserved. 9 1-2 74 80 Cited By :36

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166 placentae from multiple pregnancies (including three triplets and 17 monochorral) have been studied by injection corrosion technique, using cellulose acetate buterite in acetone, under continuous pressure within physiological limits. It has been shown that vascular anastomoses in twin placentae are usually multiple. The direct type is frequently found in monochorial twin placentae and is mostly arterial or venous in nature. The indirect type is observed more commonly in dichorial twin placentae and is mostly arteriovenous in nature. Both types are almost universally found in monochorial monoamniotic placentae. The presence of direct anastomotic channels has a highly significant association with the incidence of marginal vessels and an exaggeration of parameters of stress to an abnormal quantum – both singly and in combinations of three or more - and is independent of the pattern of branching. In the ontogenetic time-sequence perspective, direct anastomoses, marginal vessels and parameters of stress in a twin placenta can be regarded as different phases of the sequelae of an altered vascular relationship caused by disturbances in the vicinity of the 12th week of gestation. It has been further shown that direct vascular anastomoses are a greater risk to the twins than indirect ones. The importance of early and timely recognition of such channels, by an examination of twin placentae for the presence of marginal vessels, is stressed.

We examine the use of the inverse titration method for determining the ionization constant of weak organic bases when the basic form of the substance is highly insoluble in aqueous solutions. The inverse titration involves progressive dissolution of the precipitate of the insoluble basic form through addition of a strong acid, and determination of the total solubility at each step with a suitable analytical technique. Analysis of the experimental data allows the simultaneous determination of the ionization constant and the solubility of the basic form. We use dibucaine, a local anaesthetic, and analyze its total solubility after each acid addition using UV spectrophotometry. This simple experiment allows the accurate determination of the pKa of the compound at various temperatures, but provides only a rough estimate of the solubility of the basic form.