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1.
Z Rheumatol ; 80(10): 995-1003, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33006674

RESUMEN

BACKGROUND: Hand function in rheumatoid arthritis (RA) is a major determinant of functional ability. OBJECTIVE: To explore hand dysfunction in RA patients and to investigate the role of ultrasonography and nerve conduction studies in detecting factors affecting hand dysfunction. PATIENTS AND METHODS: One hundred RA patients were included in this cross-sectional study and subgrouped into those with a weak hand grip (group A) and those with a good hand grip (group B). Ultrasonographic examinations and nerve conduction studies were performed. Multiple regression analysis and receiver operating characteristic curves were used. RESULTS: The age of enrolled patients was 45.16 ± 11.66 years, 88% were females. Patients in group A had poorer hand function and quality of life compared to those in group B (P < 0.001). Using musculoskeletal ultrasonography (MSUS), higher scores of synovial proliferation, bone erosion, and cartilage damage were found in group A. Hands with weak grip strength had reduced sensory median and ulnar conduction velocity than those with good grip (P = 0.02 and 0.01, respectively). The grip strength test had 92% sensitivity and 95% specificity for prediction of hand dysfunction, while upon combining synovial proliferation with ulnar nerve sensory latency and the grip strength test, the greatest sensitivity (98%) was reached with 55% specificity. CONCLUSION: Median and ulnar sensory conduction changes together with signs of chronic inflammation and joint destruction in MSUS are prevalent in patients with poor hand grip. Combined grip strength, ulnar nerve sensory conduction study, and synovial proliferation could represent a sensitive predictor of hand dysfunction in RA.


Asunto(s)
Artritis Reumatoide , Fuerza de la Mano , Adulto , Artritis Reumatoide/diagnóstico por imagen , Estudios Transversales , Femenino , Mano/diagnóstico por imagen , Humanos , Persona de Mediana Edad , Conducción Nerviosa , Calidad de Vida , Ultrasonografía
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt C: 1718-27, 2015 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-25467662

RESUMEN

Complexes of VO(2+), Cr(3+), Co(2+), Ni(2+), Cu(2+), Zn(2+), Cd(2+) and Hg(2+) ions with N(-)(2,4-dinitrophenyl)-2-mercaptoacetohydrazide (H2L) have been prepared and characterized on the basis of elemental analysis, molar conductance, thermal (TGA, DTGA), spectral (IR, NMR, UV-Visible, MS) and magnetic measurements. The IR spectra show that H2L behaves in a mononegative and/or binegative bidentate manner. The sulfate bridged the two complex molecules in [Cu(HL)(H2O)2(½SO4)]⋅3H2O. The acetate functions as a monodentate in [Ni(HL)(OAc)(H2O)3] and [Cr(HL)(OAc)2(H2O)(EtOH)]. Different stereochemistries are proposed: octahedral for Cr(III), Ni(II), Hg(II) and [Cu(HL)(H2O)2(SO4)0.5]⋅3H2O, square-based pyramid for [VO(HL)2]⋅EtOH, square-planar for [Co(L)(EtOH)(H2O)]⋅H2O, [Cu(L)(H2O)2] and tetrahedral for [Zn(L)(EtOH)(H2O)], [Cd(L)(EtOH)(H2O)] and [Cu2(HL)(H2O)6]Cl3⋅H2O according to the data of electronic spectra and magnetic measurements. The TGA data support the formula and indicate the outer and inner solvents as well as the final residue. The thermodynamic parameters are calculated using the Coats-Redfern and Horowitz-Metzger methods. H2L and [Zn(L)(EtOH)(H2O)] showed the highest cytotoxic activity while H2L has a higher antioxidant activity than ascorbic acid. The ionization constant of the ligand and the stability constant of the Cu(II)H2L in absence and presence of hexamine buffer were calculated.


Asunto(s)
Antioxidantes , Complejos de Coordinación , Citotoxinas , Hidrazinas/química , Compuestos de Sulfhidrilo , Antioxidantes/síntesis química , Antioxidantes/química , Antioxidantes/farmacología , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Cristalografía por Rayos X , Citotoxinas/síntesis química , Citotoxinas/química , Citotoxinas/farmacología , Células Hep G2 , Humanos , Hidrazinas/síntesis química , Hidrazinas/farmacología , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Compuestos de Sulfhidrilo/síntesis química , Compuestos de Sulfhidrilo/química , Compuestos de Sulfhidrilo/farmacología , Termodinámica
3.
J Hazard Mater ; 158(1): 170-6, 2008 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-18313847

RESUMEN

Trivalent and hexavalent chromium have been successfully separated and estimated from different solutions using 1-(3,4-dihydroxybenzaldehyde)-2-acetylpyridiniumchloride hydrazone (DAPCH) loaded on Duolite C20 in batch and column modes. The obtained modified resin [DAPCH-Duolite C20] was identified by C, H and N analyses and infrared spectra. The presence of multi-active chelating sites gives the ability for DAPCH to bind more chromium, Cr(III) by forming stable complex and chromate by forming ion pair molecule [H(2)DAPCH-Duolite C20](2+)[Cr(2)O(7)](2-) (H(2)DAPCH-Duolite C20 is the protonated form in acidic medium). The extraction isotherms were measured at different pH. The pH was found to be the backbone for the separation procedure in which the Cr(VI) and Cr(III) ions are sorbed selectively from aqueous solution at pH 2 and 6, respectively. The sorbed ions can be eluted using different concentrations of HCl. The saturation sorption capacity (41.6 and 20.05 mg g(-1)), the preconcentration factor (150 and 200) and the detection limit (13.3 and 10.0 ppb) were calculated for Cr(III) and (VI). The loaded resin can be regenerated for at least 50 cycles. The utility of the modified resin was tested in aqueous samples and shows R.S.D. value of <4% reflecting its accuracy and reproducibility.


Asunto(s)
Bencenosulfonatos/química , Cromo/análisis , Hidrazonas/química , Resinas Sintéticas/química , Adsorción , Cromo/química , Concentración de Iones de Hidrógeno , Cinética , Temperatura
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 71(1): 73-9, 2008 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-18164649

RESUMEN

The reaction between 2-hydrazinopyridine and ethylisothiocyanate produced 4-ethyl-1-(pyridin-2-yl) thiosemicarbazide (HEPTS). Its reaction with copper fluoride, chloride, bromide, acetate, nitrate, perchlorate, sulfate, carbonate, hydroxide and copper metal produced 15 Cu(II) complexes. The copper metal is easily oxidized in aqueous-ethanol solution of HEPTS giving [Cu2(EPTS)(H2O)3(OH)3]EtOH. Different complexes for the same anion were synthesized by controlling the heating time. Characterization by elemental, thermal, magnetic and spectral (electronic, IR, mass and ESR) studies showed the formation of mono-, di-, tri- and tetra nuclear complexes. The room temperature solid state ESR spectra of the complexes show an axial spectrum with dx2-y2 ground state, suggesting distorted tetragonal geometry around Cu(II) center. The kinetic and thermodynamic parameters for the different decomposition steps in the complexes were calculated. HEPTS and its Cu(II) complexes showed high activity against gram negative bacteria; [Cu3(EPTS)2(EtOH)2Br4] has more activity.


Asunto(s)
Cobre/química , Semicarbacidas/química , Antiinfecciosos/química , Química Farmacéutica/métodos , Diseño de Fármacos , Espectroscopía de Resonancia por Spin del Electrón/métodos , Ligandos , Espectroscopía de Resonancia Magnética , Magnetismo , Metales/química , Modelos Químicos , Estructura Molecular , Semicarbacidas/análisis , Espectrofotometría Infrarroja/métodos , Espectrofotometría Ultravioleta/métodos , Temperatura
5.
Talanta ; 59(2): 383-92, 2003 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-18968921

RESUMEN

A novel tetrachlorothallate (III) (TCT)-selective membrane sensor consisting of tetrachlorothallate (III)-2,3,5-triphenyl-2-H-tetrazolium ion pair dispersed in a PVC matrix plasticized with dioctylphthalate is described. The electrode shows a stable, near-Nernstian response for 1x10(-3)-4x10(-6) M thallium (III) at 25 degrees C with an anionic slope of 56.5+/-0.5 over the pH range 3-6. The lower detection limit and the response time are 2x10(-6) M and 30-60 s, respectively. Selectivity coefficients for Tl(III) relative to a number of interfering substances were investigated. There is negligible interference from many cations and anions; however, iodide and bromide are significantly interfere. The determination of 0.5-200 mug ml(-1) of Tl(III) in aqueous solutions shows an average recovery of 99.0% and a mean relative standard deviation of 1.4% at 50.0 mug ml(-1). The direct determination of Tl(III) in spiked wastewater gave results that compare favorably with those obtained by the atomic absorption spectrometric method. The electrode was successfully applied for the determination of thallium in zinc concentrate. Also the tetrachlorothallate electrode has been utilized as an end point indicator electrode for the determination of thallium using potentiometric titration.

6.
Anal Sci ; 18(11): 1235-40, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12458709

RESUMEN

A simple, selective and sensitive procedure is described for the preconcentration by flotation followed by spectrophotometric determination of trace amounts of Cd(II). Cadmium forms an intense red 1:2 complex with phenanthraquinone monophenylthiosemicarbazone (PPT) at pH > or = 6. The colored Cd-PPT complex was floated quantitatively with oleic acid (HOL) surfactant at pH 6.5, exhibiting maximum absorbance at 520 nm and having a molar absorptivity of 2.4 x 10(5) L mol(-1) cm(-1). The stability constant of the formed complex is 1.5 x 10(12); log K = 12.2. Beer's law was obeyed over the concentration range 0.01-0.34 mg/L. The Sandell sensitivity and relative standard deviation are 0.4 ng/cm2 and 2.6%, respectively. The results obtained spectrophotometrically were compared to those obtained by AAS analysis. The analytical parameters affecting flotation and hence determination have been thoroughly investigated. The proposed procedure was successfully applied to the determination of Cd(II) traces in certified and real human hair samples as well as in natural waters. The structure of the complex formed and the mechanism of flotation were proposed.


Asunto(s)
Cadmio/análisis , Cadmio/química , Fenantrenos/química , Espectrofotometría/métodos , Tiosemicarbazonas/química , Calibración , Cabello/química , Humanos , Concentración de Iones de Hidrógeno , Iones , Estructura Molecular , Ácido Oléico/química , Sensibilidad y Especificidad , Soluciones/química , Temperatura
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