Novel Low-Cost Tracheo-Innominate Artery Fistula Bleed Simulator.

Tracheo-innominate artery fistulas are a rare complication of indwelling tracheotomies with a very high mortality rate. Due to the rare occurrence of this surgical emergency, most medical providers have little to no training or experience in recognizing, stabilizing, and repairing this life-threatening condition. Simulation of rare emergencies helps close knowledge gaps of medical providers at all levels. Although many providers may never experience these emergencies throughout their careers in clinical medicine, it is imperative that they distinguish and apply techniques for temporizing these life-threatening conditions in order to decrease patient mortality. This novel, low-cost, and easy-to-implement simulation is geared towards this goal and has been successfully tested in small group simulations at one academic center in San Antonio, Texas.

A Novel Case of Sudden Monocular Blindness Caused by Undiagnosed Granulomatous Disease Presenting with Acute Ophthalmic Artery Occlusion.

Ophthalmic artery occlusion is a rare condition with a high morbidity, typically associated with cardiovascular disease and embolic or thrombotic phenomena. We present an atypical case of a 22-year-old active duty airman without comorbidities, who presented with acute, painless, monocular vision loss, found to have a right-sided, ophthalmic artery occlusion. The etiology for his vision loss was likely secondary to a granulomatous process at the orbital apex, causing compressive ischemia.

Reactions of dicobalt octacarbonyl with dinucleating and mononucleating bis(imino)pyridine ligands.

This work focuses on the application of dicobalt octacarbonyl (Co2(CO)8) as a metal precursor in the chemistry of formally low-valent cobalt with redox-active bis(imino)pyridine [NNN] ligands. The reactions of both mononucleating mesityl-substituted bis(aldimino)pyridine (L1) and dinucleating macrocyclic xanthene-bridged di(bis(aldimino)pyridine) (L2) with Co2(CO)8 were investigated. Independent of the metal-to-ligand ratio (1 : 1 or 1 : 2 ligand to Co2(CO)8), the reaction of the dinucleating ligand L2 with Co2(CO)8 produces a tetranuclear complex [Co4(L2)(CO)10] featuring two discrete [Co2[NNN](CO)5] units. In contrast, a related mononucleating bis(aldimino)pyridine ligand, L1, produces different species at different ligand to Co2(CO)8 ratios, including dinuclear [Co2(CO)5(L1)] and zwitterionic [Co(L1)2][Co(CO)4]. Interestingly, [Co4(L2)(CO)10] features metal-metal bonds, and no bridging carbonyls, whereas [Co2(CO)5(L1)] contains cobalt centers bridged by one or two carbonyl ligands. In either case, treatment with excess acetonitrile leads to disproportionation to the zwitterionic [Co[NNN](NCMe)2][Co(CO)4] units. The electronic structures of the complexes described above were studied with density functional theory. All the obtained bis(imino)pyridine complexes serve as catalysts for cyclotrimerization of methyl propiolate, albeit their reactivity is inferior compared with Co2(CO)8.

Cooperative bimetallic reactivity of a heterodinuclear molybdenum-copper model of Mo-Cu CODH.

The synthesis of a heterodinucleating ligand LH2 (LH2 = (E)-3-(((2,7-di-tert-butyl-9,9-dimethyl-5-((pyridin-2-ylmethylene)amino)-9H-xanthen-4-yl)amino)methyl)benzene-1,2-diol) was undertaken toward a functional model of the bimetallic active site found in Mo-Cu carbon monoxide dehydrogenase (Mo-Cu CODH), and to understand the origins of heterobimetallic cooperativity exhibited by the enzyme. LH2 features a hard potentially dianionic catechol chelate for binding Mo(vi) and a soft iminopyridine chelate for binding Cu(i). Treatment of LH2 with either Cu(i) or M(vi) (M = Mo, W) sources leads to the anticipated site-selective incorporation of the respective metals. While both [CuI(LH2)]+ and [MVIO3(L)]2- complexes are stable in the solid state, [MVIO3(L)]2- complexes disproportionate in solution to give [MVIO2(L)2](NEt4)2 complexes, with [MVIO4]2- as the by-product. The incorporation of BOTH Mo(vi) and Cu(i) into L forms a highly reactive heterobimetallic complex [MoVIO3CuI(L)](NEt4)2, whose formation and reactivity was interrogated via1H NMR/UV-vis spectroscopy and DFT calculations. These studies reveal that the combination of the two metals triggers oxidation reactivity, in which a nucleophilic Mo(vi) trioxo attacks Cu(i)-bound imine. The major product of the reaction is a crystallographically characterized molybdenum(vi) complex [Mo(L')O2](NEt4) coordinated by a modified ligand L' that contains a new C-O bond in place of the imine functionality. This observed hydroxylation reactivity is consistent with the postulated first step of Mo-Cu CODH (nucleophilic attack of the Mo(vi)-oxo on the Cu(i)-bound electrophilic CO) and xanthine oxidoreductase (nucleophilic attack of Mo(vi)-oxo on the electrophilic xanthine carbon).

Divergent reactivity of a new dinuclear xanthene-bridged bis(iminopyridine) di-nickel complex with alkynes.

The reaction of a dinucleating bis(iminopyridine) ligand L bearing a xanthene linker (L = N,N'-(2,7-di-tert-butyl-9,9-dimethyl-9H-xanthene-4,5-diyl)bis(1-(pyridin-2-yl)methanimine)) with Ni2(COD)2(DPA) (COD = cyclooctadiene, DPA = diphenylacetylene) leads to the formation of a new dinuclear complex Ni2(L)(DPA). Ni2(L)(DPA) can also be obtained in a one-pot reaction involving Ni(COD)2, DPA and L. The X-ray structure of Ni2(L)(DPA) reveals two square-planar Ni centers bridged by a DPA ligand. DFT calculations suggest that this species features NiI centers antiferromagnetically coupled to each other and their iminopyridine ligand radicals. Treatment of Ni2(L)(DPA) with one equivalent of ethyl propiolate (HCCCO2Et) forms the Ni2(L)(HCCCO2Et) complex. Addition of the second equivalent of ethyl propiolate leads to the observation of cyclotrimerised products by 1H NMR spectroscopy. Carrying out the reaction under catalytic conditions (1 mol% of Ni2(L)(DPA), 24 h, room temperature) transforms 89% of the substrate, forming primarily benzene products (triethyl benzene-1,2,4-tricarboxylate and triethyl benzene-1,3,5-tricarboxylate) in 68% yield, in a ca. 5 : 1 relative ratio. Increasing catalyst loading to 5 mol% leads to the full conversion of ethyl propiolate to benzene products; no cyclotetramerisation products were observed. In contrast, the reaction is significantly more sluggish with methyl propargyl ether. Using 1 mol% of the catalyst, only 25% conversion of methyl propargyl ether was observed within 24 h at room temperature. Furthermore, methyl propargyl ether demonstrates the formation of cyclooctatetraenes in significant amounts at a low catalyst concentration, whereas a higher catalyst concentration (5 mol%) leads to benzene products exclusively. Density functional theory was used to provide insight into the reaction mechanism, including structures of putative dinuclear metallocyclopentadiene and metallocycloheptatriene intermediates.

A Pilot Study of Changes in Environmental Knowledge and Behaviors among Head Start Employees and Parents Following Environmental Health Training in Webb County, TX.

Head Start centers in Webb County, Texas primarily serve low-income Hispanic families disproportionately affected by environmental exposures. A total of 560 parents and employees attended environmental trainings. Pre- and post-assessments measured whether the trainings were effective at improving related knowledge and behaviors. A total of 152 parents and 94 employees signed consent forms. Only the 64 parents and 50 employees who completed all questionnaires were included in the data analysis. Paired t tests and McNemar tests found significant improvements in knowledge and behaviors related to multiple environmental topics (p < 0.05). Mean scores out of eleven for knowledge before and immediately after were 9.69 (95 % CI 9.44, 9.94) and 10.58 (95 % CI 10.42, 10.74), respectively. Mean scores out of ten for behavior before and 1 month after training were 8.00 (95 % CI 7.71, 8.29) and 9.29 (95 % CI 9.10, 9.48), respectively. This pilot study found improved knowledge and behaviors following environmental health training.

Translating an evidence-based diabetes education approach into rural african-american communities: the "wisdom, power, control" program.

Purpose. The aim of this exploratory study was to assess the efficacy of the "Wisdom, Power, Control" diabetes self-management education (DSME) program with regard to diabetes knowledge, self-efficacy, self-care, distress level, and A1C in an African-American population. Methods. A prospective, quasi-experimental, repeated-measure design was employed to measure these outcomes. Study participants were assessed at baseline, 6 weeks post-intervention, and at a 3-month A1C follow-up. Results. A total of 103 participants were recruited from the intervention counties, and 14 were identified from the control counties. At the post-test, participants in the intervention group reported a significantly higher level of diabetes knowledge (Δ = 9.2%, P <0.0001), higher self-efficacy (Δ = 0.60, P <0.0001), more self-care behaviors (Δ = 0.48, P <0.0001), lower distress level (Δ = -0.15, P = 0.05), and higher health status (Δ = 0.49, P = <0.0001). About 56% of the intervention group completed all six classes, and 25% attended five classes. Conclusions. Findings from this study demonstrate the initial success of translating a culturally adapted DSME program into rural African-American communities. The study highlights important lessons learned in the process of implementing this type of program in a real-world setting with a minority population.

An attenuating role of a WASP-related protein, WASP-B, in the regulation of F-actin polymerization and pseudopod formation via the regulation of RacC during Dictyostelium chemotaxis.

The WASP family of proteins has emerged as important regulators that connect multiple signaling pathways to regulate the actin cytoskeleton. Dictyostelium cells express WASP, as well as a WASP related protein, WASP-B, endoded by wasB gene. WASP-B contains many of the domains present in WASP. Analysis of wild type, wasB null cells revealed that WASP-B is required for proper control of F-actin polymerization in response to a cAMP gradient. Due to the lack of tight control on actin polymerization, wasB null cells exhibited higher level of F-actin polymerization. wasB(-) cells extend more de novo pseudopods laterally and their average life span is longer than those of wild type cells, causing more turns and inefficient chemotaxis. YFP-WASP-B appears to be uniformly distributed in the cytosol and shows no translocation to cortical membrane upon cAMP stimulation. Active RacC pull-down assay reveals that the level of active RacC in wasB(-) cells is significantly higher than wild type cells. Moreover, the distribution of active RacC is not localized in wasB(-) cells. We conclude that chemotaxis defects of wasB(-) cells are likely to result from the aberrant regulation of RacC activation and localization.

ß-arrestin 2-dependent activation of ERK1/2 is required for ADP-induced paxillin phosphorylation at Ser(83) and microglia chemotaxis.

Microglia play crucial roles in increased inflammation in the central nervous system upon brain injuries and diseases. Extracellular ADP has been reported to induce microglia chemotaxis and membrane ruffle formation through P2Y(12) receptor. In this study, we examined the role of ERK1/2 activation in ADP-induced microglia chemotaxis. ADP stimulation increases the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and paxillin phosphorylation at Tyr(31) and Ser(83) . Inhibition of ERK1/2 significantly inhibited paxillin phosphorylation at Ser(83) and the retraction of membrane ruffles, causing inefficient chemotaxis. Close examination of dynamics of focal adhesion (FA) formation with green fluorescent protein-paxillin revealed that the disassembly of FAs in U0126-treated cells was significantly impaired. Depletion of ß-Arrestin 2 (ß-Arr2) with short hairpin RNA markedly reduced the phosphorylation of ERK1/2 and Pax/Ser(83) , indicating that ß-Arr2 is required for ERK1/2 activation upon ADP stimulation. A large fraction of phosphorylated ERK1/2 and ß-Arr2 were translocated and co-localized at focal contacts in the newly forming lamellipodia. Examination of kinetics and rate constant of paxillin formation and disassembly revealed that the phosphorylation of paxillin at Tyr(31) by c-Src appears to be involved in adhesion formation upon ADP stimulation while Ser(83) required for adhesion disassembly.

Functional roles of VASP phosphorylation in the regulation of chemotaxis and osmotic stress response.

Vasodilator-stimulated phosphoprotein (VASP) plays crucial roles in controlling F-actin-driven processes and growing evidence indicates that VASP function is modulated by phosphorylation at multiple sites. However, the complexity of mammalian system prevents the clear understanding of the role of VASP phosphorylation. In this study, we took advantage of Dictyostelium which possesses only one member of the Ena/VASP family to investigate the functional roles of VASP phosphorylation. Our results demonstrated that hyperosmotic stress and cAMP stimulation cause VASP phosphorylation. VASP phosphorylation plays a negative role for the early steps of filopodia/microspikes formation. VASP phosphorylation appears to modulate VASP localization at the membrane cortex and its interactions with WASP and WIPa. Analysis of chemotaxis of cells expressing VASP mutants showed that VASP phosphorylation is required for the establishment of cell polarity under a cAMP gradient.