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1.
Foot Ankle Spec ; 15(2): 179-184, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33269645

RESUMO

The purpose of this study is to determine if arthrodesis, compared with open reduction and internal fixation (ORIF), produces favorable American Orthopaedic Foot and Ankle Society (AOFAS) and visual analogue scale (VAS) scores, and to determine if differences in complication, revision surgery, and secondary arthrodesis rates exist for patients with Lisfranc fracture/dislocation injuries. Searches were performed in PubMed using the keywords "Lisfranc fracture," "metatarsal fracture," "ORIF," "open reduction internal fixation," "arthrodesis," and "fusion." These criteria left 183 articles for review. Exclusions left 21 articles and 2 translations of Chinese abstracts. Data analysis was performed using Student's 2-sample t test for samples of equal variance, and chi-square test for goodness of fit. The t test revealed a significant difference (P = .03) between the average AOFAS score for patients who underwent primary arthrodesis (84.7 ± 6.14) compared with those who were treated with ORIF (78.9 ± 5.09). There was no significant difference for the average VAS scores (P = .33) of the arthrodesis and ORIF groups. The complication rate of arthrodesis patients was significantly lower than ORIF patients (P = .04), and the rates of revision surgery (P = .22) and secondary arthrodesis (P = .53) were not significant between the groups. The results of this study indicate that arthrodesis may be a better surgical option than ORIF, due to the higher functional scores and the lower complication rate.Levels of Evidence: Level III: A meta-analysis.


Assuntos
Fixação Interna de Fraturas , Fraturas Ósseas , Artrodese/métodos , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Humanos , Redução Aberta , Estudos Retrospectivos , Resultado do Tratamento
2.
JAMIA Open ; 1(1): 15-19, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31984315

RESUMO

OBJECTIVE: The rapid adoption of health information technology (IT) coupled with growing reports of ransomware, and hacking has made cybersecurity a priority in health care. This study leverages federal data in order to better understand current cybersecurity threats in the context of health IT. MATERIALS AND METHODS: Retrospective observational study of all available reported data breaches in the United States from 2013 to 2017, downloaded from a publicly available federal regulatory database. RESULTS: There were 1512 data breaches affecting 154 415 257 patient records from a heterogeneous distribution of covered entities (P < .001). There were 128 electronic medical record-related breaches of 4 867 920 patient records, while 363 hacking incidents affected 130 702 378 records. DISCUSSION AND CONCLUSION: Despite making up less than 25% of all breaches, hacking was responsible for nearly 85% of all affected patient records. As medicine becomes increasingly interconnected and informatics-driven, significant improvements to cybersecurity must be made so our health IT infrastructure is simultaneously effective, safe, and secure.

3.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 7): 949-953, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28775858

RESUMO

The zinc(II) atom in the title compound, [Zn(C48H31N4)(CF3SO3)](CF3SO3)·1.5CH2Cl2, adopts a distorted five-coordinate square-pyramidal geometry. It is coordinated by one tri-fluoro-methane-sulfonate ligand and four N atoms of the N2-[(benzo[h]quinolin-2-yl)meth-yl]-N2'-[(benzo[h]quinolin-2-yl)methyl-idene]-1,1'-binaphthyl-2,2'-di-amine ligand. The complex is present as a single-stranded P-helimer monohelical structure incorporating π-π and/or σ-π inter-actions. One of the imine bonds present in the original ligand framework is reduced, leading to variations in bond lengths and torsion angles for each side of the ligand motif. The imine-bond reduction also affects the bond lengths involving the metal atom with the N-donor atoms located on the imine bond. There are two mol-ecules of the complex in the asymmetric unit. One of the mol-ecules exhibits positional disorder within the coordinating tri-fluoro-methane-sulfonate ion making the mol-ecules symmetric-ally non-equivalent.

4.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 7): 936-940, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28775855

RESUMO

The first FeIII atom in the solvated title compound, [Fe2Cl4O(C26H28N4)]·CHCl3, adopts a distorted six-coordinate octa-hedral geometry. It is coordinated by one chloride ligand, four N atoms from the (1R,2R)-N,N'-bis-[(quinolin-2-yl)methyl]cyclo-hexane-1,2-di-amine ligand, and a bridging oxido ligand attached to the second FeIII atom, which is also bonded to three chloride ions. A very weak intra-molecular N-H⋯Cl hydrogen bond occurs. In the crystal, the coordination complexes stack in columns, and a grouping of six such columns create channels, which are populated by disordered chloro-form solvent mol-ecules. Although the Fe-Cl bond lengths for the two metal atoms are comparable to the mean Fe-Cl bond lengths as derived from the Cambridge Structural Database, the Fe-O bond lengths are notably shorter. The solvent chloro-form mol-ecule exhibits 'flip' disorder of the C-H moiety in a 0.544 (3):0.456 (3) ratio. The only directional inter-action noted is a weak C-H⋯Cl hydrogen bond.

5.
Dalton Trans ; 41(16): 4998-5009, 2012 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-22407327

RESUMO

The coordination chemistry of four enantiopure tetradentate bis(iminoquinoline) ligands with nickel(II) salts is reported. The previously reported ligands CBQ, CPQ, BBQ, and BPQ result from the condensation of (1R,2R)-cyclohexyldiamine or (R)-BINAM with two equivalents of 2-formylbenzo[h]quinoline or 8-isopropyl-2-quinolinecarboxaldehyde {CBQ = (1R,2R)-cyclohexanediamine-N,N'-bis(benzo[h]quinoline-2-ylmethylene), CPQ = (1R,2R)-cyclohexanediamine-N,N'-bis[[(8-isopropyl)-2-quinolinyl]methylene], BBQ = [(R)-1,1'-binaphthalene]-2,2'-diamine-N,N'-bis(benzo[h]quinoline-2-ylmethylene), BPQ = [(R)-1,1'-binaphthalene]-2,2'-diamine-N,N'-bis[[(8-isopropyl)-2-quinolinyl]methylene]}. Reaction of NiI(2) with the (1R,2R)-cyclohexyl ligands gives the mononuclear distorted trigonal-bipyramidal (TBP) complexes [Ni(N(3)-CBQ)I(2)] and [Ni(N(3)-CPQ)I(2)]. Incomplete iodide abstraction from [Ni(N(3)-CPQ)I(2)] with AgOTf leads to partial replacement of the iodide with hydroxide from adventitious water to give [Ni(N(3)-CPQ)I(1.6)(OH)(0.4)] (distorted TBP). The corresponding reaction with [Ni(N(3)-CBQ)I(2)] again fails to remove all of the iodide, resulting instead in conversion to the syn dinuclear [Ni(2)(CBQ)(µ-X)(2)I(2)] (X = Cl(0.925)I(0.075)) complex, where chloride abstraction from the solvent (CH(2)Cl(2)) has resulted in a mixed halide system and the metal centers are square-pyramidal. Reaction of Ni(OTf)(2) with CBQ leads to the isolation of the octahedral cation [Ni(CMBQ)(2)](2+), with CMBQ [(1R,2R)-cyclohexanediamine-mono-N-(benzo[h]quinoline-2-ylmethylene)] being the partial hydrolysis product of CBQ. [Ni(CMBQ)(2)][OTf](2) crystallizes as a 1:1 mixture of P and M helical diastereomers. The coordination of NiI(2) with the (R)-BINAM derived ligands yields the anti dinuclear P-helical complexes [Ni(2)(BBQ)(µ-I)(2)I(2)] and [Ni(2)(BPQ)(µ-I)(2)I(2)]: one nickel ion is coordinated in each bidentate iminoquinoline pocket and the geometry at the metal centers is distorted square-pyramidal. Characterisation by (1)H NMR, UV-Vis, electronic circular dichroism (ECD) spectroscopy, combustion analysis, and HRMS is reported in addition to structural and halide abstraction studies.

6.
J Neuroimaging ; 22(3): 215-24, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20977531

RESUMO

INTRODUCTION: Transcranial Doppler (TCD) is a physiological ultrasound test with established safety and efficacy. Although imaging devices may be used to depict intracranial flow superimposed on structural visualization, the end-result provided by imaging duplex or nonimaging TCD is sampling physiological flow variables through the spectral waveform assessment. SUMMARY OF RESULTS: Clinical indications considered by this multidisciplinary panel of experts as established are: sickle cell disease, cerebral ischemia, detection of right-to-left shunts (RLS), subarachnoid hemorrhage, brain death, and periprocedural or surgical monitoring. The following TCD-procedures are performed in routine in- and outpatient clinical practice: complete or partial TCD-examination to detect normal, stenosed, or occluded intracranial vessels, collaterals to locate an arterial obstruction and refine carotid-duplex or noninvasive angiographic findings; vasomotor reactivity testing to identify high-risk patients for first-ever or recurrent stroke; emboli detection to detect, localize, and quantify cerebral embolization in real time; RLS-detection in patients with suspected paradoxical embolism or those considered for shunt closure; monitoring of thrombolysis to facilitate recanalization and detect reocclusion; monitoring of endovascular stenting, carotid endarterectomy, and cardiac surgery to detect perioperative embolism, thrombosis, hypo- and hyperperfusion. CONCLUSION: By defining the scope of practice, these standards will assist referring and reporting physicians and third parties involved in the process of requesting, evaluating, and acting upon TCD results.


Assuntos
Transtornos Cerebrovasculares/diagnóstico por imagem , Radiologia/normas , Ultrassonografia Doppler Transcraniana/normas , Humanos , Estados Unidos
7.
Inorg Chem ; 47(3): 1120-6, 2008 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-18166045

RESUMO

A new Schiff-base ligand is prepared by a two-step reaction of 3-formylsalicylic acid and (1R, 2R)-diaminocyclohexane in alcoholic solvents. The 1:1 condensation product exists as a zwitterion in the solid state and forms pleated hydrogen-bonded sheets. Metalation of the ligand with divalent iron, nickel, cobalt, and zinc resulted in the formation of double-stranded monohelices with exclusively M-helicity. Each complex has two tridentate ligands, with the carboxylic acid groups remaining uncoordinated. In the crystal lattice, these complexes form extended M-helical strands through intermolecular hydrogen bonding interactions. Metalation of the ligand with copper salts resulted in a distinctly different type of complex, in which the ligand has transformed into a symmetric tetradentate salen ligand with uncoordinated carboxylic acid groups.


Assuntos
Bases de Schiff , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estereoisomerismo
8.
Dalton Trans ; (42): 4788-96, 2007 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-17955131

RESUMO

The synthesis of two 2-formylquinolines is reported via the Skraup method followed by SeO(2) oxidation. Each aldehyde is condensed with (1R,2R)-diaminocyclohexane and (R)-BINAM, yielding four enantiomerically-pure bis(imine-quinoline) ligands. The neutral ligands are reacted with ZnCl(2) to give complexes with bis(bidentate) coordination of ZnCl(2) units. X-Ray structural characterization of three complexes shows them to have a single-stranded helical motif, with M helicity, except in one case where a 1:1 mixture of M and P helices is seen. The ligands and complexes are further characterized spectroscopically by solution (1)H and (13)C NMR, UV-vis and ECD.

9.
Dalton Trans ; (15): 1520-7, 2007 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-17404653

RESUMO

The synthesis of the polyaromatic aldehyde 1-hydroxybenz[a]anthracene-2-carboxaldehyde is reported via a seven step protocol from 9,10-dihydroanthracene, with an overall yield of 30%. Two equivalents of the aldehyde are condensed with (R)-1,1'-binaphthyl-2,2'-diamine to produce a new binaphthyl-salen ligand, which is subsequently complexed to iron(II) and zinc(II) ions. The ligand and complexes are characterized by single-crystal X-ray crystallography. The complexes have distinct helical structures with overlapping benz[a]anthryl sidearms, and only M-helices are observed. The ligand and complexes are further characterized by solution (1)H and (13)C NMR spectroscopy as well as UV-visible and ECD spectroscopies. These studies indicate that there is a single component in solution, consistent with the solid state characterization.

10.
Inorg Chem ; 45(25): 10034-6, 2006 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-17140203

RESUMO

An enantiomerically pure C2-symmetric salen ligand with benz[a]anthracene siderams produces M helical complexes (FeII and ZnII) in solution. Interconversion to produce a 1:1 mixture of helical conformers in the solid state is possible, despite overlapped sidearms.

11.
Chem Commun (Camb) ; (37): 4693-5, 2005 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-16175295

RESUMO

A new chiral binaphthyl salen ligand with rigid polyaromatic sidearms gives monohelical complexes (Fe(II) and Zn(II)) of predetermined handedness.


Assuntos
Compostos Ferrosos/síntese química , Ferro/química , Compostos Organometálicos/síntese química , Zinco/química , Cristalografia por Raios X , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular
13.
J Am Chem Soc ; 126(26): 8216-31, 2004 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-15225063

RESUMO

A series of enantiopure C1-symmetric metallocenes, [(SiMe2)2[eta5-C5H(CHMe2)2][eta5-C5H2((S)-CHMeCMe3)]]ZrCl2, (S)-2, [(SiMe2)2[eta5-C5H(CHEt2)2][eta5-C5H2((S)-CHMeCMe3)]]ZrCl2, (S)-6, and [(SiMe2)2[eta5-C5HCy2][eta5-C5H2((S)-CHMeCMe3)]]ZrCl2, (S)-7 (Cy = cyclohexyl), zirconocene dichlorides that have an enantiopure methylneopentyl substituent on the "upper" cyclopentadienyl ligand, and diastereomerically pure precatalysts, [(SiMe2)2[eta5-C5H((S)-CHMeCy)(CHMe2)][eta5-C5H3]]ZrCl2, (S)-8a and (S)-8b, which have an enantiopure, 1-cyclohexylethyl substituent on the "lower" cyclopentadienyl ligand, has been synthesized for use in the polymerization of chiral alpha-olefins. When activated with methylaluminoxane, these metallocenes show unprecedented activity for the polymerization of bulky racemic monomers bearing substitution at the 3- and/or 4-positions. Due to the optically pure nature of these single site catalysts, they effect kinetic resolution of racemic monomers: the polymeric product is enriched with the faster reacting enantiomer, while recovered monomer is enriched with the slower reacting enantiomer. The two components are easily separated. For most olefins surveyed, a partial kinetic resolution was achieved (s = k(faster)/k(slower) approximately 2), but, in one case, the polymerization of 3,4-dimethyl-1-pentene, high levels of separation were obtained (s > 15). (13)C NMR spectroscopy of poly(3-methyl-1-pentene) produced with (S)-2 indicates that the polymers are highly isotactic materials. X-ray crystal structure determinations for (S)-2, [(SiMe2)2[eta5-C5H(CHMe2)2][eta5-C5H2((S)-CHMeCMe3)]]Zr(SC6H5)2, (S)-6, and (S)-7 have been used in combination with molecular mechanics calculations to examine the prevailing steric interactions expected in the diastereomeric transition states for propagation during polymerization. Precatalysts (S)-8a and (S)-8b are less selective polymerization catalysts for the kinetic resolution of 3-methyl-1-pentene than are (S)-2, (S)-6, and (S)-7.

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