Hypertonic Saline Administration via Intraosseous Access During Symptomatic Hyponatremia

Hyponatremia is a common lab finding. Symptomatology varies greatly and can depend on the degree of hyponatremia and its chronicity. Causes of hyponatremia are also vast and include heart failure, renal injury, liver disease, and gastrointestinal losses, or it can be induced by medication. Treatment depends on the suspected etiology. However, in life-threatening conditions such as seizures or coma, urgent 3% saline is required. Administration of 3% saline is usually through peripheral and central IV access. This case report highlights an alternative route in administering 3% saline, intraosseous vascular access, when other options have been exhausted.

A Rare Cause of Exudative Pleural Effusion in a Female

Yellow nail syndrome is an extremely rare syndrome that presents with a clinical triad of thickened yellow nails, lymphedema, and recurring pulmonary manifestations (pleural effusion, chronic cough, or bronchiectasis), usually in the population above the age of 50 years. We describe a case of yellow nail syndrome in a 48-year-old lady who presented with the typical classical triad of this syndrome.

Aphasia as the Initial Presentation of Acute Otomastoiditis in an Elderly Male

Acute otomastoiditis is a potentially life-threatening condition. It is relatively uncommon in elderly patients and is usually seen as a complication of acute otitis media. Limited studies are available on this uncommon disease in the elderly, and thus the clinical course of the disease is not fully understood. Proper use of antibiotics for acute otitis media has markedly decreased the incidence of acute otomastoiditis. We describe a case of a 76-year-old male with acute otomastoiditis complicated by cerebellopontine angle epidural abscess who presented with a chief complaint of sudden onset of global aphasia, which is an unusual presentation for acute otomastoiditis. The patient eventually required medical and surgical intervention. To the best of our knowledge, acute otomastoiditis presenting with sudden onset of global aphasia has not been previously described in the literature. This case illustrates how multidisciplinary team involvement is vital in the management of these uncommon cases.

Atrioesophageal fistula with meningitis: A rare complication of atrial fibrillation ablation, case report and literature review

Atrioesophageal fistula is a rare, devastating complication of atrial fibrillation ablation, reportedly occurring in 0.015–0.04% of catheter ablations. A 66-year-old African American male with a past medical history of chronic atrial fibrillation status post recent radiofrequency ablation and on chronic anticoagulation with rivaroxaban presented with left upper extremity numbness, tingling, and transient weakness. He was admitted for a cerebrovascular accident workup; a 12-lead electrocardiogram revealed atrial fibrillation and magnetic resonance imaging of the brain was consistent with multifocal embolic infarcts. Hospital course was further complicated by persistent high-grade fevers, gram-positive bacteremia, and worsening mental status requiring mechanical ventilation. Lumbar puncture was consistent with bacterial meningitis. Transthoracic echocardiogram was negative for vegetations. Computed tomography angiography of the chest with intravenous contrast revealed an outpouching off the posterior wall of the left atrium at the level of the inferior pulmonary vein, consistent with an atrioesophageal fistula. We present this case to highlight the clinical features of a rare but potentially fatal complication from a commonly performed procedure requiring prompt recognition and life-saving intervention.

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Atrioesophageal fistula (AEF) is a rare, devastating complication of atrial fibrillation ablation.

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AEF-related complications vary in presentation and should be suspected within three-months of radiofrequency ablation.

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Repeat imaging is reasonable in patients with high clinical suspicion.

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Treatment options include surgical repair and conservative management with esophageal stenting.

Influence of the concentration of CO2 and SO2 on the absorption of CO2 by a lithium orthosilicate-based absorbent

A novel, high temperature solid absorbent based on lithium orthosilicate (Li(4)SiO(4)) has shown promise for postcombustion CO(2) capture. Previous studies utilizing a clean, synthetic flue gas have shown that the absorbent has a high CO(2) capacity, >25 wt %, along with high absorption rates, lower heat of absorption and lower regeneration temperature than other solids such as calcium oxide. The current effort was aimed at evaluating the Li(4)SiO(4) based absorbent in the presence of contaminants found in typical flue gas, specifically SO(2), by cyclic exposure to gas mixtures containing CO(2), H(2)O (up to 25 vol. %), and SO(2) (up to 0.95 vol. %). In the absence of SO(2), a stable CO(2) capacity of ∼ 25 wt % over 25 cycles at 550 °C was achieved. The presence of SO(2), even at concentrations as low as 0.002 vol. %, resulted in an irreversible reaction with the absorbent and a decrease in CO(2) capacity. Analysis of SO(2)-exposed samples revealed that the absorbent reacted chemically and irreversibly with SO(2) at 550 °C forming Li(2)SO(4). Thus, industrial application would require desulfurization of flue gas prior to contacting the absorbent. Reactivity with SO(2) is not unique to the lithium orthosilicate material, so similar steps would be required for other absorbents that chemically react with SO(2).

Regulators of serine/threonine protein phosphatases at the dawn of a clinical era?

Reversible phosphorylation is a key mechanism for regulating the biological activity of many human proteins that affect a diverse array of cellular processes, including protein-protein interactions, gene transcription, cell-cycle progression and apoptosis. Once viewed as simple house keeping enzymes, recent studies have made it eminently clear that, like their kinase counterparts, protein phosphatases are dynamic and highly regulated enzymes. Therefore, the development of compounds that alter the activity of specific phosphatases is rapidly emerging as an important area in drug discovery. Because >98% of protein phosphorylation occurs on serine and threonine residues, the identification of agents that alter the activity of specific serine/threonine phosphatases seems especially promising for drug development in the future. This review is focused on the enzymes encoded by the PPP-gene family, which includes PP1, PP2A, PP2B, PP4, PP5, PP6 and PP7. The structure/functions of human phosphatases will be addressed briefly, as will the natural product inhibitors of PP1-PP6 (e.g. okadaic acid, microcystins, nodularin, cantharidin, calyculin A, tautomycin, and fostriecin). The development of chimeric antisense oligonucleotides that support RNAase H mediated degradation of the targeted mRNA has resulted in compounds capable of specifically suppressing the expression of PP5 (ISIS 15534) and PP1gamma 1 (ISIS 14435) in human cells. Such compounds have already proven useful for the validation of drug targets, and if difficulties associated with systemic delivery of antisense oligonucleotides can be overcome, antisense is poised to have a major impact on the clinical management of many human disorders.

Identification of an estrogen-inducible phosphatase (PP5) that converts MCF-7 human breast carcinoma cells into an estrogen-independent phenotype when expressed constitutively

The proliferation of many estrogen receptor (ER)-positive breast cancer cells depends on estradiol, and tumors arising from these cells are often responsive initially to treatment with selective ER modulators, which produce an antiestrogen effect. However, tumors that are refractory to the antiestrogenic effects of selective ER modulators often reemerge, and the prognosis for these patients is poor because of the lack of additional effective therapy. Accordingly, deciphering the cellular events associated with estrogen-dependent growth and the subsequent outgrowth of tumors with an estrogen-independent phenotype is of considerable interest. Here we show that the expression of PP5, an evolutionarily conserved Ser/Thr phosphatase that functions as an inhibitor of glucocorticoid- and p53-induced signaling cascades leading to growth suppression, is responsive to 17beta-estradiol (E(2)) in ER-positive human breast carcinoma cells (MCF-7). Northern analysis revealed that E(2)-induced PP5 expression is blocked by treatment with tamoxifen, and a consensus ER recognition element was identified in the PP5 promoter. The PP5-ER recognition element associates with human ERs and confers E(2)-induced transcriptional activation to reporter plasmids. The specific inhibition of PP5 expression ablates E(2)-mediated proliferation in MCF-7 cells without having an apparent effect on E(2)-induced expression of c-myc or cyclin D1. Thus, although critical for cell growth, PP5 likely acts either downstream or independently of c-Myc and Cyclin D1. To further characterize the role of PP5 in E(2)-regulated growth control, we constructed stable MCF-7 cell lines in which the expression of PP5 was placed under the control of tetracycline-regulated transactivator and operator plasmids. Studies with these cells revealed that the constitutive overexpression of PP5 affords E(2)-dependent MCF-7 cells with the ability to proliferate in E(2)-depleted media. Together, these studies indicate that E(2)-induced PP5 expression functions to enhance E(2)-initiated signaling cascades leading to cell division and that aberrant PP5 expression may contribute to the development of MCF-7 cells with an estrogen-independent phenotype.

Maternal effects of the short integument mutation on embryo development in Arabidopsis

Maternal gene products deposited in an animal egg determine the polarity of embryonic axes and regulate embryonic cell-cell communication important for morphogenesis. Here we report the first maternal-effect embryo-defective mutation discovered in a plant. Recessive mutations in the SHORT INTEGUMENT (SIN1) gene in Arabidopsis were previously shown to influence ovule development and flowering time. Here we show that a sin1 mutation has a pronounced maternal effect on zygotic embryo development. A homozygous sin1 mutant embryo is normal when nursed by a sin1/+ heterozygous maternal sporophyte. Strikingly, a sin1 or a sin1/+ embryo that is nursed by a sin1 homozygous maternal sporophyte develops morphogenetic defects in the apical-basal and radial axes. The defects resemble those seen in some zygotic-effect embryonic pattern formation mutants. These results imply that in maternal cells the SIN1 gene either codes for or controls the production of a diffusible morphogen necessary for proper zygotic embryogenesis.

SHORT INTEGUMENT (SIN1), a gene required for ovule development in Arabidopsis, also controls flowering time

The short integument (sin1) mutation causes a female-specific infertility, and a defect in the control of time to flowering in Arabidopsis. Female sterility of Sin- plants is due to abnormal ovule integument development and aberrant differentiation of the megagametophyte in a subset of ovules. An additional defect of sin1 mutants is the production of an increased number of vegetative leaf and inflorescence primordia leading to delayed flowering. The delayed flowering phenotype of sin1-1 is not due to a defect in the perception of day length periodicity or in gibberellic acid metabolism. Phenotypes of double mutant combinations of sin1 with terminalflower (tfl1) indicate that SIN1 activity is required for precocious floral induction typical in a tfl1 mutant. Unexpectedly, sin1-1 tfl1-1 plants do not make pollen, thus revealing a novel role for TFL1 in the anther. Early flowers of sin1-1 ap1-1 double mutants are transformed to long inflorescence-like shoots. A genetic model for the role of SIN1 in flowering time control is proposed.

Orofacial dyskinesia in Down's syndrome

Of 54 patients aged 30-60 years with a diagnosis of Down's syndrome, 38 had evidence of orofacial dyskinesia, assessed using the AIMS. There was a strong relationship between the presence of such movements and the severity of mental handicap. No relationship was found between abnormal movements and age. None of the patients had previously taken neuroleptic medication.

Imaging Surface Atomic Structure by Means of Auger Electrons

Measurements of the complete angular distribution of Auger electrons emitted from well-defined platinum[111] single-crystal surfaces have led to the discovery that the distributions are composed of "silhouettes" of surface atoms "back lit" by emission from atoms deeper in the solid. Theoretical simulations of Auger electron angular distributions based upon atomic point emitters and spherical atomic scatterers of uniform cross section are in close agreement with these experimental results, but opposite to previous theoretical predictions. In view of the definitive results obtained and the straightforward agreement between theory and experiment, angular distribution Auger microscopy (ADAM) is useful for direct imaging of interfacial structure and investigation of electron-solid interactions in the physical and biological sciences and engineering. Applicability of ADAM is illustrated by images obtained for monolayers of silver and iodine on platinum[111].

Permselectivity and ion-exchange properties of Eastman-AQ polymers on glassy carbon electrodes

Eastman-AQ55D is a new poly(ester sulfonic acid) cation exchanger available in a commercial dissolved form. Films of this polymer were coated onto glassy carbon surfaces, and the resulting electrodes exhibit attractive permselectivity, ion-exchange, and antifouling properties. Substantial improvement in the selectivity is observed as a result of excluding anionic species from the surface. The charge-selective behavior is demonstrated in the presence of a variety of compounds of neurological significance. A rapid response to dynamic changes in the concentration of cationic and neutral species is observed. The polymer strongly binds multiply charged counterions. Cyclic voltammetry is used to determine the quantity of incorporated ions as a function of time, concentration, and other variables. The oxidation of hydrogen peroxide is catalyzed when Ru(bpy)3(2+) is incorporated in the coating. The film can also protect the substrate electrode from foulants present in the contacting solution. These features, as well as the low cost, simple coating procedure, strong adherence to surfaces, and versatility, make the Eastman-AQ55D polymer well-suited for a variety of electro-analytical applications.