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1.
Metallomics ; 15(4)2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36918206

RESUMEN

Platinum(II) coordination compounds are widely applied in clinics as anticancer drugs. In this review, we provide a summary of the reports on cytotoxic properties of platinum(II) complexes of selenium donor ligands along with a brief description of their structural features. It has been observed that the platinum(II) complexes of selenones and selenoethers display reasonable antitumor properties and in some cases their cytotoxic activity is greater than cisplatin. The complexes containing NH3 ligands along with selenones were found to exhibit better cytotoxicity compared to the binary Pt-selenone complexes. The mechanistic insights showed that these complexes exert antitumor activity through reactive oxygen species (ROS) generation and induction of apoptosis. The platinum-selenoether coordination compounds can self-assemble into spherical aggregates capable of self-delivery. The self-assembled Pt-selenium aggregates induce cell apoptosis via ROS, which leads to high selectivity between cancer cells and normal cells in cytotoxicity assays.


Asunto(s)
Antineoplásicos , Selenio , Platino (Metal)/farmacología , Platino (Metal)/química , Selenio/farmacología , Ligandos , Especies Reactivas de Oxígeno , Compuestos Organoplatinos/farmacología , Compuestos Organoplatinos/química , Antineoplásicos/farmacología , Antineoplásicos/química
2.
Pak J Med Sci ; 31(5): 1182-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26649010

RESUMEN

OBJECTIVE: To compare the neuro-radiologic findings in Systemic lupus erythematosus (SLE) patients with and without antiphospholipid antibodies (aPL) in different neuro-psychiatric manifestations. METHODS: This cross-sectional comparative study was carried out at King Khalid University Hospital, a tertiary care teaching hospital, Riyadh, Saudi Arabia from June 2012 to January 2015. Ninety seven SLE patients with neuro-psychiatric manifestations were included in the study and divided into two groups. Group I (50 patients) SLE with aPL and group II (47 patients) SLE without aPL. We compared Demographic features, clinical manifestations and magnetic resonance imaging (MRI) brain findings. RESULTS: Demographic and clinical characteristics of two groups were similar. In Group-I, anticardiolipin antibodies (aCL) were most common (86%). In patients with headache, most of the patients in Group-I had white matter hyperintensities (WMHIs) (50% vs 27%) while most of the patients in Group-II had normal MRI brain (38% vs 73%). Similarly WMHIs were found more in Group-I patients with seizures (60% vs 21%), while ischemia/infarction, atrophy and normal MRI were found in Group-II. MRI brain in patients with neurological deficit and psychiatric disorder were not much different in both the groups. CONCLUSION: We found no statistically significant differences in frequencies of MRI brain abnormalities in SLE patients with and without aPL antibodies. Each of the three aPL may have a variable effect on the brain.

3.
Pak J Med Sci ; 31(1): 70-5, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25878617

RESUMEN

OBJECTIVE: To uncover the pulmonary manifestations of Systemic Lupus Erythematosus (SLE) patients alone and to compare findings with antiphospholipid syndrome (APS) associated with SLE. METHODS: This cross sectional comparative study was carried out at King Khalid University Hospital (KKUH)/King Saud University (KSU), a tertiary care hospital, Riyadh, Kingdom of Saudi Arabia. From June 2012 to March 2014, 96 diagnosed SLE patients with respiratory symptoms were included in the study and divided into two groups. Group one included SLE without antiphospholipid syndrome (APS) and group two SLE with APS. We compared Demographic features, clinical manifestations and findings of chest X-Ray, Arterial Blood Gases, Pulmonary function tests, six minute walk test, ventilation perfusion scan, echocardiography and chest high resolution computed tomography. RESULTS: Demographic and clinical characteristics of two groups were similar. Previous history of deep venous thrombosis (3% vs 27.6%, p=0.001), pulmonary embolism (3% vs34.5%, p<0.0001) and abortions (7.5% vs 27.6%, p=0.019) were significantly more in group two. Levels of Anticardiolipin antibody (0% vs 100%, p<0.0001) and lupus anticoagulant (1.5% vs 79.3%, p<0.0001) were also significantly higher in group two. Hypoxemia measured by pulse oximetry (43.3% vs 65.5% p=0.045, pulmonary Arterial Hypertension (15.5% vs 39.3% p=0.014)), and pulmonary embolism (3.4% vs 21.4% p=0.013) and ventilation perfusion mismatch on V/Q scan (1.5% vs 24.1% p=0.001) were more frequent in group two. CONCLUSION: Hypoxemia, pulmonary embolism and pulmonary arterial hypertension were significantly high in SLE patients with APS, requiring long term anticoagulation and treatment and close follow-up.

4.
Talanta ; 115: 308-13, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-24054596

RESUMEN

The electro-enhanced solid-phase microextraction (EE-SPME) method was developed for the determination of endocrine disruptor compounds such as phthalate esters and bisphenol A in human blood and seawater samples. After EE-SPME, samples were analyzed by gas chromatography-mass spectrometry (GC-MS). In this approach, commercial SPME fiber was used in direct-immersion mode with an applied potential to extract di-ethyl phthalate, di-butyl phthalate, benzyl butyl phthalate and bisphenol A. The applied potential facilitates and enhances the extraction efficiency of the target analytes. Various experimental conditions influencing performance of the EE-SPME such as extraction time, applied potential and ionic strength were optimized. Under the optimum conditions, EE-SPME was more efficient than a conventional SPME approach. Very good linearity was observed for all analytes in a range between 1 and 100 µg L(-1) with correlation of determination (R(2)) between 0.963 and 0.996. The limits of a detection based signal-to-noise of 3 were from 0.004 to 0.15 µg L(-1). The reproducibility of EE-SPME was evaluated and the relative standard deviations were between 1.0% and 5.0% (n=9). The proposed method was applied to human blood samples stored in transfusion bags and seawater. Results showed that the proposed EE-SPME was simple and suitable for trace level analysis.


Asunto(s)
Compuestos de Bencidrilo/aislamiento & purificación , Disruptores Endocrinos/aislamiento & purificación , Fenoles/aislamiento & purificación , Ácidos Ftálicos/aislamiento & purificación , Agua de Mar/química , Microextracción en Fase Sólida/métodos , Compuestos de Bencidrilo/sangre , Electricidad , Disruptores Endocrinos/sangre , Ésteres , Cromatografía de Gases y Espectrometría de Masas , Humanos , Límite de Detección , Concentración Osmolar , Fenoles/sangre , Ácidos Ftálicos/sangre , Reproducibilidad de los Resultados , Relación Señal-Ruido , Solventes , Factores de Tiempo
5.
J Sep Sci ; 36(12): 2003-9, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23936915

RESUMEN

Dispersive liquid-liquid microextraction method was developed for the determination of the amount of phthalate esters in bottled drinking water samples and dispersive liquid-liquid microextraction samples were analyzed by GC-MS. Various experimental conditions influencing the extraction were optimized. Under the optimized conditions, very good linearity was observed for all analytes in a range between 0.05 and 150 µg/L with coefficient of determination (R²) between 0.995 and 0.999. The LODs based on S/N = 3 were 0.005-0.22 µg/L. The reproducibility of dispersive liquid-liquid microextraction was evaluated. The RSDs were 1.3-5.2% (n = 3). The concentrations of phthalates were determined in bottled samples available in half shell. To understand the leaching profile of these phthalates from bottled water, bottles were exposed to direct sunlight during summer (temperature from 34-57°C) and sampled at different intervals. Result showed that the proposed dispersive liquid-liquid microextraction is suitable for rapid determination of phthalates in bottled water and di-n-butyl, butyl benzyl, and bis-2-ethylhexyl phthalate compounds leaching from bottles up to 36 h. Thereafter, degradation of phthalates was observed.


Asunto(s)
Agua Potable/análisis , Ésteres/aislamiento & purificación , Microextracción en Fase Líquida/métodos , Ácidos Ftálicos/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Ésteres/análisis , Cromatografía de Gases y Espectrometría de Masas , Ácidos Ftálicos/análisis , Contaminantes Químicos del Agua/análisis
6.
J Sep Sci ; 35(23): 3381-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22997165

RESUMEN

A sensitive and accurate method for the determination of two model phenoxy herbicides, 4-chloro-2-methylphenoxy acetic acid and 4-chloro-2-methylphenoxy propanoic acid, in water is explained. This method utilizes a simple phase transfer catalyst-assisted microextraction with simultaneous derivatization. Factors affecting the performance of this method including pH of the aqueous matrix, temperature, extraction duration, type and amount of derivatization reagents, and type and amount of the phase transfer catalyst are examined. Derivatization and the use of phase transfer catalyst have proven to be especially vital for the resolution of the analytes and their sensitive determination, with an enrichment factor of 288-fold for catalyzed over noncatalyzed procedure. Good linearity ranging from 0.1 to 80 µg L(-1) with correlation of determination (r(2) ) between 0.9890 and 0.9945 were obtained. Previous reported detection limits are compared with our new current method. The low LOD for the two analytes (0.80 ng L(-1) for 4-chloro-2-methylphenoxy propanoic acid and 3.04 ng L(-1) for 4-chloro-2-methylphenoxy acetic acid) allow for the determination of low concentrations of these analytes in real samples. The absence of matrix effect was confirmed through relative recovery calculations. Application of the method to seawater and tap water samples was tested, but only 4-chloro-2-methylphenoxy propanoic acid at concentrations between 0.27 ± 0.01 and 0.84 ± 0.06 µg L(-1) was detected in seawater samples.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Herbicidas/análisis , Herbicidas/aislamiento & purificación , Microextracción en Fase Líquida/métodos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificación , Agua Dulce/química , Agua de Mar/química
7.
Talanta ; 87: 284-9, 2011 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22099680

RESUMEN

In this study, functionalized polysulfone membrane has been utilized as a sorbent for the extraction of chlorinated hydrocarbons (CHCs) in water samples. Two different functionalized polysulfones (i) phosphonic acid functionalized polysulfone (PPSU-A) with different forms (cross-linked and non cross-linked) membranes and (ii) phosphonic ester functionalized polysulfone (PPSU-E) with different forms (cross-linked and non cross-linked) were evaluated for the extraction of CHCs in water. A 10 ml of spiked water sample was extracted with 50mg piece of the functionalized membrane. After extraction, the membrane was desorbed by organic solvent and the extract was analyzed by gas chromatography-mass spectrometry. Eight CHCs, 1,3,5-trichlorobenzene (1,3,5-TCB), 1,2,3-trichlorobenzene (1,2,3-TCB), 1,1,2,3,4,4-hexachloro-1,3-butadiene (HCBD), 1,2,4-trichloro-3-methylbenzene (TCMB), 1,2,3,4-tetrachlorobenzene (1,2,3,4-TeCB), 1,2,4,5-tetrachlorobenzene (1,2,4,5-TeCB), pentachlorobenzene (PeCB) and hexachlorobenzene (HCB) were used as model compounds. Experimental parameters such as extraction time, desorption time, types of polymer membrane as well the nature of desorption solvent were optimized. Using optimum extraction conditions calibration curves were linear with coefficients of determination between 0.9954 and 0.9999 over wide range of concentrations (0.05-100 µgl(-1)). The method detection limits (at a signal-to-noise ratio of 3) were in the range of 0.4-3.9 ng l(-1). The proposed method was evaluated for the determination of CHCs in drinking water samples.


Asunto(s)
Fraccionamiento Químico/métodos , Hidrocarburos Clorados/aislamiento & purificación , Membranas Artificiales , Polímeros/química , Sulfonas/química , Contaminantes Químicos del Agua/aislamiento & purificación , Agua/análisis , Agua Potable/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Hidrocarburos Clorados/análisis , Límite de Detección , Contaminantes Químicos del Agua/análisis
8.
Artículo en Inglés | MEDLINE | ID: mdl-19241266

RESUMEN

Efficient removal of phenol was carried out using laser induced photocatalyis process in the presence of Fe(2)O(3) semiconductor catalysts, and under UV laser irradiation. Parametric dependence of the removal process was investigated carefully by variation of laser irradiation time, laser energy, and concentration of the catalysts. pH measurements were also carried out to understand the photocatalytic process for removal of phenol. Maximum phenol removal achieved in this process was more than 90% during 1 hour of laser irradiation. This is considered highly efficient as compared to conventional setups using lamps. Reaction kinetics for the removal of phenol was also studied, and a reaction rate of 0.017 min(- 1) was estimated, following first order kinetics.


Asunto(s)
Compuestos Férricos/química , Fenoles/aislamiento & purificación , Rayos Ultravioleta , Catálisis , Concentración de Iones de Hidrógeno , Cinética
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