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1.
Ann Med Surg (Lond) ; 86(6): 3757-3761, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38846823

RESUMEN

Introduction: Primary spinal cord oligodendrogliomas (PSO) are sporadic tumors that arise from oligodendrocytes in the central nervous system (CNS). They can affect adults and children and make up about 2% of all intramedullary (IM) spinal tumors. Here, the authors present the second case in the literature of a primary spinal oligodendroglioma with intracranial extension. Presentation: A 28-year-old right-handed female presented to our emergency room severely malaised with left-sided hemiparesis, numbness, tingling, and urinary retention with positive Babinski and negative Hoffmann. MRI showed a widespread heterogeneous mass extending from the medulla to C7 with syringomyelia inferior to the mass. The mass was removed surgically, and her neurological condition improved rapidly. The gross, pathological exams, and immunohistochemistry confirmed the diagnosis of oligodendroglioma. Discussion: Up until 2017, there have been 60 documented cases of PSO in the literature and we have found two more cases in our search between 2017 and 2023. Also, there has been only one case recorded with an intracranial extension, making our case the 63rd PSO case and the second one with cranial extension. Conclusion: The golden standard for imaging is MRI. Surgical excision is the main treatment in the literature. Single-stage laminectomy showed promising results and surgical resection was the critical intervention to which the patient responded. This matches what was stated in the literature that surgery is the primary mode of treatment in PSO patients.

2.
J Biomed Biotechnol ; 2012: 828139, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22719210

RESUMEN

The nitro group of 2-nitroimidazole (NIM) enters the tumor cells and is bioreductively activated and fixed in the hypoxia cells. 1,4,8,11-tetraazacyclotetradecane (N4) has shown to be a stable chelator for (99m)Tc. The present study was aimed to develop (99m)Tc-cyclam-2-nitroimidazole ((99m)Tc-N4-NIM) for tumor hypoxia imaging. N4-NIM precursor was synthesized by reacting N4-oxalate and 1,3-dibromopropane-NIM, yielded 14% (total synthesis). Cell uptake of (99m)Tc-N4-NIM and (99m)Tc-N4 was obtained in 13762 rat mammary tumor cells and mesothelioma cells in 6-well plates. Tissue distribution of (99m)Tc-N4-NIM was evaluated in breast-tumor-bearing rats at 0.5-4 hrs. Tumor oxygen tension was measured using an oxygen probe. Planar imaging was performed in the tumor-bearing rat and rabbit models. Radiochemical purity of (99m)Tc-N4-NIM was >96% by HPLC. Cell uptake of (99m)Tc-N4-NIM was higher than (99m)Tc-N4 in both cell lines. Biodistribution of (99m)Tc-N4-NIM showed increased tumor-to-blood and tumor-to-muscle count density ratios as a function of time. Oxygen tension in tumor tissue was 6-10 mmHg compared to 40-50 mmHg in normal muscle tissue. Planar imaging studies confirmed that the tumors could be visualized clearly with (99m)Tc-N4-NIM in animal models. Efficient synthesis of N4-NIM was achieved. (99m)Tc-N4-NIM is a novel hypoxic probe and may be useful in evaluating cancer therapy.


Asunto(s)
Neoplasias/diagnóstico por imagen , Compuestos de Organotecnecio/farmacocinética , Radiofármacos/farmacocinética , Animales , Hipoxia de la Célula/fisiología , Femenino , Compuestos Heterocíclicos con 1 Anillo/química , Compuestos Heterocíclicos con 1 Anillo/farmacocinética , Humanos , Masculino , Imagen Molecular/métodos , Neoplasias/metabolismo , Neoplasias/patología , Nitroimidazoles/química , Nitroimidazoles/farmacocinética , Compuestos de Organotecnecio/química , Oxígeno/metabolismo , Conejos , Trazadores Radiactivos , Cintigrafía , Radiofármacos/química , Ratas , Ratas Endogámicas F344 , Distribución Tisular , Microambiente Tumoral
3.
J Biomed Biotechnol ; 2012: 671708, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22496612

RESUMEN

The purpose of this study was to develop an efficient way to synthesize (99m)Tc-O-[3-(1,4,8,11-tetraazabicyclohexadecane)-propyl]-tyrosine ((99m)Tc-N4-Tyrosine), a novel amino acid-based radiotracer, and evaluate its potential in breast cancer gamma imaging. Precursor N4-Tyrosine was synthesized using a 5-step procedure, and its total synthesis yield was 38%. It was successfully labeled with (99m)Tc with high radiochemical purity (>95%). Cellular uptake of (99m)Tc-N4-Tyrosine was much higher than that of (99m)Tc-N4 and the clinical gold standard (18)F-2-deoxy-2-fluoro-glucose ((18)F-FDG) in rat breast tumor cells in vitro. Tissue uptake and dosimetry estimation in normal rats revealed that (99m)Tc-N4-Tyrosine could be safely administered to humans. Evaluation in breast tumor-bearing rats showed that although (99m)Tc-N4-Tyrosine appeared to be inferior to (18)F-FDG in distinguishing breast tumor tissue from chemical-induced inflammatory tissue, it had high tumor-to-muscle uptake ratios and could detect breast tumors clearly by planar scintigraphic imaging. (99m)Tc-N4-Tyrosine could thus be a useful radiotracer for use in breast tumor diagnostic imaging.


Asunto(s)
Compuestos Heterocíclicos con 1 Anillo/síntesis química , Compuestos Heterocíclicos con 1 Anillo/farmacocinética , Neoplasias Mamarias Experimentales/diagnóstico por imagen , Compuestos de Organotecnecio/síntesis química , Compuestos de Organotecnecio/farmacocinética , Radiofármacos/síntesis química , Radiofármacos/farmacocinética , Tirosina/análogos & derivados , Animales , Línea Celular Tumoral , Femenino , Fluorodesoxiglucosa F18/farmacocinética , Inflamación/diagnóstico por imagen , Inflamación/metabolismo , Neoplasias Mamarias Experimentales/metabolismo , Dosis de Radiación , Trazadores Radiactivos , Cintigrafía , Ratas , Ratas Endogámicas F344 , Distribución Tisular , Tirosina/farmacocinética
4.
Transplant Proc ; 54(8): 2263-2269, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36243574

RESUMEN

BACKGROUND: Racial and ethnic minorities are disproportionally affected by end-stage liver disease. Unfortunately, disparities in referrals to liver transplantation (LT), organ allocation, and posttransplant outcomes exist in this population. METHODS: We performed a retrospective analysis of patients over the age of 18 years undergoing LT in the United States using the Scientific Registry of Transplant Recipients from 2002 to 2016. We evaluated factors associated with patient and graft outcomes and explored the effect of race and ethnicity along with social variables. RESULTS: During the study time period, 78,999 patients received LT. Of these, 60,102 were non-Hispanic White (NHW), 7988 were African American (AA), and 10,909 were Hispanic. AA had significantly lower patient survival, graft survival, and death-censored graft survival at both 1 and 5 years when compared to NHW. Conversely, at 1 and 5 years, patient survival and graft survival were significantly higher for Hispanics compared to NWH. In addition, AA had significantly lower survival outcomes compared to Hispanics. On multivariate analysis after controlling for race/ethnicity, age, AA race, diagnosis, and deceased donor were independent risk factors for patient death and graft failure. CONCLUSIONS: Despite socioeconomic disadvantages seen among Hispanics, this population appears to have improved short- and long-term survival after LT compared to NHW and AA.


Asunto(s)
Trasplante de Hígado , Estados Unidos , Humanos , Adulto , Persona de Mediana Edad , Trasplante de Hígado/efectos adversos , Estudios Retrospectivos , Minorías Étnicas y Raciales , Hispánicos o Latinos , Supervivencia de Injerto
5.
J Biomed Biotechnol ; 2011: 276907, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21541217

RESUMEN

PURPOSE: This study was to develop an efficient synthesis of (99m)Tc-O-[3-(1,4,8,11-tetraazabicyclohexadecane)-propyl]-α-methyl tyrosine ((99m)Tc-N4-AMT) and evaluate its potential in cancer imaging. METHODS: N4-AMT was synthesized by reacting N4-oxalate and 3-bromopropyl AMT (N-BOC, ethyl ester). In vitro cellular uptake kinetics of (99m)Tc-N4-AMT was assessed in rat mammary tumor cells. Tissue distribution of the radiotracer was determined in normal rats at 0.5-4 h, while planar imaging was performed in mammary tumor-bearing rats at 30-120 min. RESULTS: The total synthesis yield of N4-AMT was 14%. Cellular uptake of (99m)Tc-N4-AMT was significantly higher than that of (99m)Tc-N4. Planar imaging revealed that (99m)Tc-N4-AMT rendered greater tumor/muscle ratios than (99m)Tc-N4. CONCLUSIONS: N4-AMT could be synthesized with a considerably high yield. Our in vitro and in vivo data suggest that (99m)Tc-N4-AMT, a novel amino acid-based radiotracer, efficiently enters breast cancer cells, effectively distinguishes mammary tumors from normal tissues, and thus holds the promise for breast cancer imaging.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Compuestos de Organotecnecio/síntesis química , Cintigrafía/métodos , Radiofármacos/síntesis química , alfa-Metiltirosina/síntesis química , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión , Femenino , Compuestos de Organotecnecio/química , Compuestos de Organotecnecio/farmacocinética , Radiofármacos/química , Radiofármacos/farmacocinética , Ratas , Ratas Endogámicas F344 , Distribución Tisular , alfa-Metiltirosina/química , alfa-Metiltirosina/farmacocinética
6.
Pak J Pharm Sci ; 20(1): 47-51, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17337428

RESUMEN

Successive hexane, chloroform and methanol extracts of the rhizome of Hedychium coronarium Koen. (HC) were subjected to evaluate analgesic and anti-inflammatory activities in animal model. In acetic acid-induced writhing test, the chloroform and methanol extract at doses of 400 mg/kg body weight elicited 27.23 and 40.59% inhibition of writhing reflex respectively. Both the chloroform and methanol extracts showed significant elongation of tail flick time (41.15 and 61.32% elongation respectively) at 400 mg/kg body weight. In carrageenan induced rat paw edema test, the chloroform and methanol extracts at a dose of 400 mg/kg body weight showed statistically significant (P<0.01) inhibition of paw edema by 27.46 and 32.48%, respectively at the third hour after carrageenan injection.


Asunto(s)
Analgésicos/farmacología , Antiinflamatorios/farmacología , Edema/prevención & control , Dolor/prevención & control , Zingiberaceae , Ácido Acético , Analgésicos/uso terapéutico , Animales , Antiinflamatorios/uso terapéutico , Carragenina , Modelos Animales de Enfermedad , Edema/inducido químicamente , Ratones , Dolor/inducido químicamente , Dimensión del Dolor , Umbral del Dolor/efectos de los fármacos , Extractos Vegetales/farmacología , Ratas , Ratas Long-Evans , Rizoma , Factores de Tiempo
7.
J Inorg Biochem ; 99(3): 795-804, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15708801

RESUMEN

A series of platinum(II) and (IV) monoadducts of the type [Pt(II)(DACH)LCl]NO3 and [Pt(IV)(DACH)trans-(X)2LCl]NO3 (where DACH=trans-1R,2R-diaminocyclohexane, L=adenine, guanine, hypoxanthine, cytosine, adenosine, guanosine, inosine, cytidine, 9-ethylguanine (9-EtGua), or 1-methylcytosine and X=hydroxo or acetato ligand) have been synthesized and characterized by elemental analysis and by 1H and 195Pt nuclear magnetic resonance (NMR) spectroscopy. The crystal structure of the model nucleobase complex [Pt(IV)(trans-1R,2R-diaminocyclohexane)trans-(acetate)2(9-EtGua)Cl]NO3.H2O was determined using a single crystal X-ray diffraction method. The compound crystallized in the monoclinic space group P2(1), with a=10.446(2) A, b=22.906(5) A, c=10.978(2) A, Z=4, and R=0.0718, based upon the total of 11,724 collected reflections. In this complex, platinum had a slightly distorted octahedron geometry owing to the presence of a geometrically strained five-member ring. The two adjacent corners of the platinum plane were occupied by the two amino nitrogen of DACH, whereas, the other two equatorial positions occupied by chloride ion and 9-ethylguanine. The remaining two axial positions were occupied by the oxygen atoms of acetato ligands. The DACH ring was in a chair configuration. An intricate network of intermolecular hydrogen bonds held the crystal lattice together. Some of these synthesized models of DACH-Pt-DNA adducts have good in vitro cytotoxic activity against the cisplatin-sensitive human cancer ovarian A2780 cell line (IC50=1-8 microM). Interestingly, a substituted nucleobase (9-ethylguanine) adduct was over 6-fold more potent than regular adducts. The cross-resistance factor against the 44-fold cisplatin-resistant 2780CP/clone 16 cells was about 3-9; thus, the cytotoxicity of adducts was indicative of low potency, but the resistance factors were also substantially low. These results suggest that DNA adducts of DACH-Pt are cytotoxic with low cross-resistance.


Asunto(s)
Antineoplásicos/química , Nucleósidos/química , Compuestos Organoplatinos/química , Platino (Metal)/química , Antineoplásicos/farmacología , Cisplatino/química , Cristalografía por Rayos X/métodos , Ciclohexilaminas/química , Guanina/química , Humanos , Concentración 50 Inhibidora , Modelos Moleculares , Nitratos/química , Nucleósidos/metabolismo , Compuestos Organoplatinos/farmacología , Platino (Metal)/farmacología , Relación Estructura-Actividad , Células Tumorales Cultivadas
8.
Anal Sci ; 31(5): 437-43, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25958874

RESUMEN

Silver nanoparticle (AgNP) has been synthesized using adrenaline. Adrenaline readily undergoes an autoxidation reaction in an alkaline medium with the dissolved oxygen to form adrenochrome, thus behaving as a mild reducing agent for the dissolved oxygen. This reducing behavior of adrenaline when employed to reduce Ag(+) ions yielded a large enhancement in the intensity of absorbance in the visible region. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) studies have been performed to confirm the surface morphology of AgNPs. Further, the metallic nanoparticles with size greater than 2 nm caused a strong and broad absorption band in the UV-visible spectrum called surface plasmon band or Mie resonance. The formation of AgNPs caused the large enhancement in the absorbance values with λmax at 436 nm through the excitation of the surface plasmon band. The formation of AgNPs was adopted to for the quantitative assessment of adrenaline using spectrophotometry with lower detection limit and higher precision values.


Asunto(s)
Epinefrina/análisis , Nanopartículas del Metal/química , Plata/química , Microscopía Electrónica de Transmisión , Estructura Molecular , Tamaño de la Partícula , Propiedades de Superficie , Difracción de Rayos X
9.
J Inorg Biochem ; 96(4): 452-6, 2003 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-13678810

RESUMEN

A series of new platinum(II) and platinum(IV) adducts of type [P(II)(cis-1,4-DACH)LCl]NO(3,) where cis-1,4-DACH=cis-1,4-diaminocyclohexane, and L=9-ethylguanine, 1-methylcytosine, adenine, adenosine, cytosine, cytidine, guanine, and [Pt(IV)(cis-1,4-DACH)Ltrans-(X)(2)Cl]NO(3), (where Y=hydroxo or acetato), were synthesized and characterized by elemental analysis, infrared spectroscopy, and 1H and 195Pt nuclear magnetic resonance spectroscopy.


Asunto(s)
Ciclohexilaminas/química , Ciclohexilaminas/metabolismo , Aductos de ADN/química , Aductos de ADN/metabolismo , Nucleósidos/metabolismo , Platino (Metal)/química , Ciclohexilaminas/síntesis química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Nucleósidos/química , Espectrofotometría Infrarroja
10.
Biomed Res Int ; 2013: 460619, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23936803

RESUMEN

Radiolabeled tyrosine analogs enter cancer cells via upregulated amino acid transporter system and have been shown to be superior to (18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG) in differential diagnosis in cancers. In this study, we synthesized O-[3-(19)F-fluoropropyl]-α-methyl tyrosine ((19)F-FPAMT) and used manual and automated methods to synthesize O-[3-(18)F-fluoropropyl]-α-methyl tyrosine ((18)F-FPAMT) in three steps: nucleophilic substitution, deprotection of butoxycarbonyl, and deesterification. Manual and automated synthesis methods produced (18)F-FPAMT with a radiochemical purity >96%. The decay-corrected yield of (18)F-FPAMT by manual synthesis was 34% at end-of-synthesis (88 min). The decay-corrected yield of (18)F-FPAMT by automated synthesis was 15% at end-of-synthesis (110 min). (18)F-FDG and (18)F-FPAMT were used for in vitro and in vivo studies to evaluate the feasibility of (18)F-FPAMT for imaging rat mesothelioma (IL-45). In vitro studies comparing (18)F-FPAMT with (18)F-FDG revealed that (18)F-FDG had higher uptake than that of (18)F-FPAMT, and the uptake ratio of (18)F-FPAMT reached the plateau after being incubated for 60 min. Biodistribution studies revealed that the accumulation of (18)F-FPAMT in the heart, lungs, thyroid, spleen, and brain was significantly lower than that of (18)F-FDG. There was poor bone uptake in (18)F-FPAMT for up to 3 hrs suggesting its in vivo stability. The imaging studies showed good visualization of tumors with (18)F-FPAMT. Together, these results suggest that (18)F-FPAMT can be successfully synthesized and has great potential in mesothelioma imaging.


Asunto(s)
Diagnóstico por Imagen , Radioisótopos de Flúor/química , Mesotelioma/diagnóstico por imagen , Animales , Radioisótopos de Flúor/administración & dosificación , Humanos , Ratones , Tomografía de Emisión de Positrones/métodos , Radiografía , Radiofármacos , Ratas , Distribución Tisular
11.
Nucl Med Commun ; 31(8): 699-707, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20495499

RESUMEN

OBJECTIVE: This study was to develop a (99m)Tc-labeled alpha-methyl tyrosine (AMT) using L,L-ethylenedicysteine (EC) as a chelator and to evaluate its potential in breast tumor imaging in rodents. METHODS: EC-AMT was synthesized by reacting EC and 3-bromopropyl AMT (N-BOC, ethyl ester) in ethanol/potassium carbonate solution. EC-AMT was labeled with (99m)Tc in the presence of tin (II) chloride. Rhenium-EC-AMT (Re-EC-AMT) was synthesized as a reference standard for (99m)Tc-EC-AMT. To assess the cellular uptake kinetics of (99m)Tc-EC-AMT, 13 762 rat breast cancer cells were incubated with (99m)Tc-EC-AMT for 0-2 h. To investigate the transport mechanism, the same cell line was used to conduct the competitive inhibition study using L-tyrosine. Tissue distribution of (99m)Tc-EC-AMT was determined in normal rats at 0.5-4 h. Planar imaging of breast tumor-bearing rats was performed at 30 and 90 min. The data were compared with those of (18)F-2-fluoro-2-deoxy-glucose. Blocking uptake study using unlabeled AMT was conducted to investigate the transport mechanism of (99m)Tc-EC-AMT in vivo. RESULTS: Structures of EC-AMT and Re-EC-AMT were confirmed by nuclear magnetic resonance, high performance liquid chromatography and mass spectra. In-vitro cellular uptake of (99m)Tc-EC-AMT in 13,762 cells was increased as compared with that of (99m)Tc-EC and could be inhibited by L-tyrosine. Biodistribution in normal rats showed high in-vivo stability of (99m)Tc-EC-AMT. Planar scintigraphy at 30 and 90 min showed that (99m)Tc-EC-AMT could clearly visualize tumors. (99m)Tc-EC-AMT uptake could be significantly blocked by unlabeled AMT in vivo. CONCLUSION: The results indicate that (99m)Tc-EC-AMT, a new amino acid transporter-based radiotracer, is suitable for breast tumor imaging.


Asunto(s)
Sistemas de Transporte de Aminoácidos/metabolismo , Neoplasias de la Mama/metabolismo , Cisteína/análogos & derivados , Imagen Molecular/métodos , Compuestos de Organotecnecio/química , Compuestos de Organotecnecio/síntesis química , alfa-Metiltirosina/química , Animales , Transporte Biológico/efectos de los fármacos , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Línea Celular Tumoral , Quelantes/química , Cisteína/química , Femenino , Compuestos de Organotecnecio/metabolismo , Compuestos de Organotecnecio/farmacocinética , Tomografía de Emisión de Positrones , Ratas , alfa-Metiltirosina/farmacología
12.
J Nat Med ; 63(1): 41-5, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18726560

RESUMEN

Solvent partitioning followed by column chromatography of the MeOH extract of the seeds of Swietenia mahagoni afforded two limonoids, swietenolide (1) and 2-hydroxy-3-O-tigloylswietenolide (2). The compounds were identified by spectroscopic means. The antibacterial activity of these compounds was assessed against eight multiple-drug-resistant bacterial strains (clinical isolates) by the conventional disc diffusion method. While both compounds were active against all test organisms, compound 2 displayed overall more potent activity than compound 1.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Limoninas/farmacología , Meliaceae/química , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Cromatografía en Capa Delgada , Limoninas/química , Limoninas/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología
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