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1.
ESMO Open ; 6(4): 100228, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34371382

RESUMEN

BACKGROUND: The purpose of this study was to assess the concordance of real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) detection of ESR1, PGR, ERBB2, and MKi67 messenger RNA (mRNA) in breast cancer tissues with central immunohistochemistry (IHC) in women treated within the prospective, randomized Austrian Breast and Colorectal Cancer Study Group (ABCSG) Trial 6. PATIENTS AND METHODS: We evaluated ESR1, PGR, ERBB2, and MKi67 mRNA expression by Xpert® Breast Cancer STRAT4 (enables cartridge-based RT-qPCR detection of mRNA in formalin-fixed paraffin-embedded tissues) and estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and Ki67 protein expression by IHC [in situ hybridization (ISH) for HER2 IHC 2+] in 1115 surgical formalin-fixed paraffin-embedded specimens from patients of ABCSG Trial 6. Overall percent agreement (concordance), positive percent agreement (sensitivity), and negative percent agreement (specificity) between STRAT4 and IHC were determined for each marker. The primary objective of the study was concordance between STRAT4 mRNA measurements of ESR1, PGR, ERBB2, and MKi67 with central reference laboratory IHC (and ISH for HER2 IHC 2+ cases). Time to distant recurrence was analyzed by Cox models. RESULTS: All performance targets for ER, PR, and Ki67 were met. For HER2, the negative percent agreement target but not the positive percent agreement target was met. Concordance between STRAT4 and IHC was 98.9% for ER, 89.9% for PR, 98.2% for HER2, and 84.8% for Ki67 (excluding intermediate IHC 10%-20% staining). In univariable and multivariable Cox regression analyses, all four biomarkers tested by either STRAT4 RT-qPCR or by central IHC (ISH) had a comparable time to distant recurrence indicating similar prognostic value. CONCLUSIONS: With the exception of HER2, we demonstrate high concordance between centrally assessed IHC and mRNA measurements of ER, PR, and Ki67 as well as a high correlation of the two methods with clinical outcome. Thus, mRNA-based assessment by STRAT4 is a promising new tool for diagnostic and therapeutic decisions in breast cancer.


Asunto(s)
Neoplasias de la Mama , Receptores de Progesterona , Biomarcadores de Tumor/genética , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Receptor alfa de Estrógeno/genética , Femenino , Hormonas , Humanos , Antígeno Ki-67/genética , Recurrencia Local de Neoplasia , Posmenopausia , Estudios Prospectivos , ARN Mensajero/genética , Receptor ErbB-2 , Receptores de Progesterona/genética
2.
J Exp Biol ; 223(Pt 4)2020 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-31953364

RESUMEN

Estuarine crocodiles, Crocodylus porosus, inhabit freshwater, estuarine and marine environments. Despite being known to undertake extensive movements throughout and between hypo-osmotic and hyperosmotic environments, little is known about the role of the cloaca in coping with changes in salinity. We report here that, in addition to the well-documented functional plasticity of the lingual salt glands, the middle of the three cloacal segments (i.e. the urodaeum) responds to increased ambient salinity to enhance solute-coupled water absorption. This post-renal modification of urine serves to conserve water when exposed to hyperosmotic environments and, in conjunction with lingual salt gland secretions, enables C. porosus to maintain salt and water balance and thereby thrive in hyperosmotic environments. Isolated epithelia from the urodaeum of 70% seawater-acclimated C. porosus had a strongly enhanced short-circuit current (an indicator of active ion transport) compared with freshwater-acclimated crocodiles. This enhanced active ion absorption was driven by increased Na+/K+-ATPase activity, and possibly enhanced proton pump activity, and was facilitated by the apical epithelial Na+ channel (ENaC) and/or the apical Na+/H+ exchanger (NHE2), both of which are expressed in the urodaeum. NHE3 was expressed at very low levels in the urodaeum and probably does not contribute to solute-coupled water absorption in this cloacal segment. As C. porosus does not appear to drink water of salinities above 18 ppt, observations of elevated short-circuit current in the rectum as well as a trend for increased NHE2 expression in the oesophagus, the anterior intestine and the rectum suggest that dietary salt intake may stimulate salt and possibly water absorption by the gastrointestinal tract of C. porosus living in hyperosmotic environments.


Asunto(s)
Caimanes y Cocodrilos/fisiología , Cloaca/metabolismo , Recto/metabolismo , Salinidad , Aclimatación/fisiología , Caimanes y Cocodrilos/metabolismo , Animales , Canales Epiteliales de Sodio/genética , Canales Epiteliales de Sodio/metabolismo , Transporte Iónico/fisiología , Masculino , Intercambiadores de Sodio-Hidrógeno/genética , Intercambiadores de Sodio-Hidrógeno/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/genética , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Orina/química
3.
Transplant Proc ; 50(9): 2834-2838, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30401407

RESUMEN

PURPOSE: Alveolar-capillary barrier dysfunction, characterized by alveolar protein leak and lung edema, is a common scenario following cardiopulmonary surgery and thoracic organ transplantation. Reactive oxygen species generated through lung ischemia and reperfusion (I/R) injury during surgery plays a crucial role. Niacin, also known as vitamin B3, has been demonstrated to possess antioxidative and anti-inflammatory capacity. In this study, we examine the pulmonary barrier function via capillary filtration coefficient (Kfc) following lung I/R injury with and without niacin treatment. METHODS: Studies were conducted on male Sprague-Dawley rats in 3 groups: sham-operated, lung I/R injury, and niacin-pretreated lung I/R injury group. Rats were subjected to isolated perfused lung preparation. Lung ischemia was established by continuous perfusion and stopping ventilation for 60 minutes, followed by 60 minutes of ventilation. We assessed the Kfc, lung water content, and protein concentration in the lung lavage; pulmonary oxidative stress and lung inflammation were assessed by leukocyte counts, tissue level of tumor nercrosis factor alpha (TNF-α), and tissue content of malondialdehyde (MDA), respectively. We also assessed the tissue protein level of sirtuin (silent mating type information regulation 2 homolog) 1 (SIRT1). RESULTS: Lungs subjected to I/R injury significantly increased Kfc, pulmonary oxidative stress, lung water content, and lavage leukocyte count and protein concentration (P < .05). Rats treated with niacin of 100 mg/kg/day for 4 days increased lung SIRT1 (P < .05) and attenuated lung I/R injury-induced pulmonary oxidative stress and inflammation and also improved Kfc. CONCLUSIONS: Niacin pretreatment protects lungs against I/R injury-induced barrier function impairment through the activation of SIRT1 and reduced pulmonary oxidative stress and lung inflammation.


Asunto(s)
Trasplante de Pulmón , Niacina/farmacología , Estrés Oxidativo/efectos de los fármacos , Daño por Reperfusión/prevención & control , Sirtuina 1/metabolismo , Animales , Antioxidantes/farmacología , Modelos Animales de Enfermedad , Supervivencia de Injerto/efectos de los fármacos , Supervivencia de Injerto/fisiología , Masculino , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/patología
4.
Transplant Proc ; 46(4): 1127-30, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24815144

RESUMEN

OBJECTIVE: Reperfusion of the rat kidney has been shown to up-regulate cysteinyl leukotriene-1 receptor, an asthma-associated gene in human bronchioles, and increase expression of leukotriene D4. In this study, we aimed to investigate the efficacy of MK-571, a leukotriene D4 inhibitor, against hypersensitivity induced by kidney ischemia and reperfusion (I/R)-associated acute kidney injury. METHODS: Sprague-Dawley male rats were divided into 3 study groups: a sham-operated group, a kidney I/R group, and a group treated with MK-571 before the kidney I/R injury: MK-571 (5 mg/kg) was administered intraperitoneally 15 minutes before ischemia and every 12 hours after reperfusion up to 24 hours. Ischemia was conducted by bilateral occlusion of renal pedicles for 45 minutes, followed by releasing the clamps and closing the abdominal incision. Respiratory function was tested 24 hours after reperfusion, with the use of a 2-chamber whole body plethysmograph for conscious rats. Blood samples, pulmonary bronchoalveolar lavage fluid, and lung tissues were collected at the end of study. In 10 rats, urine was collected at baseline and the end of study. RESULTS: Compared with the sham group, kidney I/R injury markedly increased enhanced pause (Penh) index during methacholine challenge test (P < .05), suggesting airway hypersensitivity; it also increased in inflammatory response and levels of hydroxyl radical production and lipid peroxidation in the lungs. In contrast, in MK-571-treated rats, Penh was muted during methacholine challenge test (P < .05). CONCLUSIONS: Kidney I/R injury induces airway hypersensitivity to methacholine challenge test and inflammatory response and oxidative stress in the lungs. Treatment with MK-571, a leukotriene D4 inhibitor, effectively attenuates airway hypersensitivity, pulmonary inflammatory response, and lung and kidney injury.


Asunto(s)
Lesión Renal Aguda/tratamiento farmacológico , Hiperreactividad Bronquial/prevención & control , Broncoconstricción/efectos de los fármacos , Broncodilatadores/farmacología , Riñón/efectos de los fármacos , Antagonistas de Leucotrieno/farmacología , Pulmón/efectos de los fármacos , Propionatos/farmacología , Quinolinas/farmacología , Daño por Reperfusión/tratamiento farmacológico , Lesión Renal Aguda/complicaciones , Lesión Renal Aguda/metabolismo , Animales , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Biomarcadores/metabolismo , Hiperreactividad Bronquial/etiología , Hiperreactividad Bronquial/metabolismo , Hiperreactividad Bronquial/fisiopatología , Broncodilatadores/administración & dosificación , Modelos Animales de Enfermedad , Esquema de Medicación , Radical Hidroxilo/metabolismo , Mediadores de Inflamación/metabolismo , Inyecciones Intraperitoneales , Riñón/metabolismo , Antagonistas de Leucotrieno/administración & dosificación , Peroxidación de Lípido/efectos de los fármacos , Pulmón/metabolismo , Pulmón/fisiopatología , Masculino , Estrés Oxidativo/efectos de los fármacos , Propionatos/administración & dosificación , Quinolinas/administración & dosificación , Ratas Sprague-Dawley , Daño por Reperfusión/complicaciones , Daño por Reperfusión/metabolismo , Factores de Tiempo
5.
Transplant Proc ; 46(4): 1135-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24815146

RESUMEN

OBJECTIVE: Acute respiratory distress syndrome (ARDS) is a common scenario associated with hepatic warm ischemia and reperfusion (I/R) injury after shock or hemorrhage. Inflammation of lung parenchyma and increase in matrix metalloprotease 9 (MMP-9) activity have been implicated in ARDS. In this study, we aimed to investigate the protective efficacy of curcumin treatment against hepatic I/R-induced lung function impairment. METHODS: Thirty Sprague-Dawley male rats were evenly divided into 3 groups: a sham group, a hepatic I/R group, and a group treated with curcumin (15 mg/kg/d) 15 minutes before ischemia and every 24 hours for the next 48 hours. Ischemia was induced by occluding the hepatic artery and portal vein for 30 minutes. The clamps were then released and the abdominal incision was closed. Pulmonary function test was conducted after 48 hours of reperfusion. We also examined serum alanine transaminase (ALT) level and degrees of tumor necrosis factor α (TNF-α) and MMP-9 activity in the lung tissue. RESULTS: Hepatic I/R injury decreased the ratio of residual volume to total lung capacity (RV/TLC), chord compliance (Cchord), and maximum midexpiratory flow (MMEF; P < .05), and increased inspiratory resistance (RI; P < .05), characterized as combined obstructive and restrictive lung disease. Treatment with curcumin markedly improved RV/TLC, Cchord, and MMEF and decreased RI (P < .05). In addition, curcumin treatment reduced serum ALT level and degrees of TNF-α level and MMP-9 activity in the lungs. CONCLUSIONS: Curcumin attenuated hepatic I/R-induced combined restrictive and obstructive lung disease by reducing lung inflammation and MMP-9 activity.


Asunto(s)
Curcumina/farmacología , Hepatopatías/tratamiento farmacológico , Hígado/cirugía , Enfermedades Pulmonares Obstructivas/prevención & control , Lesión Pulmonar/prevención & control , Pulmón/efectos de los fármacos , Metaloproteinasa 9 de la Matriz/metabolismo , Inhibidores de la Metaloproteinasa de la Matriz/farmacología , Daño por Reperfusión/tratamiento farmacológico , Isquemia Tibia/efectos adversos , Alanina Transaminasa/sangre , Animales , Biomarcadores/sangre , Citoprotección , Modelos Animales de Enfermedad , Hígado/irrigación sanguínea , Hepatopatías/etiología , Pulmón/enzimología , Pulmón/fisiopatología , Enfermedades Pulmonares Obstructivas/enzimología , Enfermedades Pulmonares Obstructivas/etiología , Enfermedades Pulmonares Obstructivas/fisiopatología , Lesión Pulmonar/enzimología , Lesión Pulmonar/etiología , Lesión Pulmonar/fisiopatología , Masculino , Ratas Sprague-Dawley , Daño por Reperfusión/etiología , Factores de Tiempo , Factor de Necrosis Tumoral alfa/metabolismo
6.
Transplant Proc ; 45(10): 3550-4, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24314956

RESUMEN

OBJECTIVES: Lung ischemia and reperfusion (I/R) injury is the major complication subsequent to cardiopulmonary bypass surgery and lung transplantation. Lung I/R injury frequently induces cardiac dysfunction leading to significant mortality. So far, the literature on therapeutic interventions in cardiac dysfunction and myocardial injury is still scarce. In this study, we examined the efficacy of N-acetylcysteine (NAC) administration against lung I/R injury-induced cardiac dysfunction. METHODS: Lung ischemia was established by occluding the left lung hilum for 60 minutes, followed by 2 hours of reperfusion. Studies were performed in 3 groups: sham-operated (same surgical procedure except vessel occlusion; N = 8), lung I/R injury (N = 12), and NAC-administered group (N = 12). The cardiac function was assessed using simultaneous left ventricular (LV) pressure and volume measured via a high-fidelity pressure-volume catheter. Myocardial injury was assessed based on serum creatine kinase muscle brain fraction (CK-MB) and troponin I (cTnI) level, and lung injury based on the degree of protein concentration in lung lavage. We also examined the degrees of myocardial lipid peroxidation and hydroxyl radical production with and without NAC. RESULTS: During lung ischemia, LV stiffness increased with relative intact contractility. After 2 hours of reperfusion, LV contractility decreased with dilated and stiffened ventricle, along with apparent myocardial and lung injury. NAC administration effectively attenuated heart and lung injury, and ameliorated impaired LV contractility and stiffening resulting from lung I/R injury. CONCLUSIONS: NAC administration reduced lung I/R-induced increases in myocardial hydroxyl radical production and lipid peroxidation, and ameliorated LV contractility and stiffening.


Asunto(s)
Acetilcisteína/farmacología , Antioxidantes/farmacología , Lesión Pulmonar/tratamiento farmacológico , Pulmón/irrigación sanguínea , Contracción Miocárdica/efectos de los fármacos , Daño por Reperfusión/tratamiento farmacológico , Disfunción Ventricular Izquierda/prevención & control , Función Ventricular Izquierda/efectos de los fármacos , Animales , Biomarcadores/sangre , Líquido del Lavado Bronquioalveolar/química , Forma MB de la Creatina-Quinasa/sangre , Citoprotección , Modelos Animales de Enfermedad , Radical Hidroxilo/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Lesión Pulmonar/sangre , Lesión Pulmonar/fisiopatología , Masculino , Miocardio/metabolismo , Miocardio/patología , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/sangre , Daño por Reperfusión/fisiopatología , Factores de Tiempo , Troponina I/sangre , Disfunción Ventricular Izquierda/sangre , Disfunción Ventricular Izquierda/patología , Disfunción Ventricular Izquierda/fisiopatología , Presión Ventricular/efectos de los fármacos
7.
Cancer ; 87(5): 278-85, 1999 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-10536353

RESUMEN

BACKGROUND: One of the limitations preventing the widespread use of fine-needle aspiration (FNA) is that it requires skill to obtain an adequate sample and well prepared smears. In this study, a new monolayer technique, the Cyto-Tek MonoPrep (MP) system, which obviates the need for smear preparation, was evaluated against conventional smear (CS) preparation for palpable breast lesions. METHODS: A total of 44 paired CS/MP breast FNA specimens were studied. The authors blindly analyzed the CS and the MP slides separately, then by a side-by-side evaluation. The two methods were compared with respect to diagnostic concordance, cellularity, cell preservation, background debris, and time needed to prepare and diagnose each case. RESULTS: An exact diagnostic correlation was present in 34 of 44 (77%) cases. The 10 noncorrelating cases were caused by decreased cellularity in the MP cases; nonetheless, 7 of these were correctly assigned to the right general diagnostic category, whereas the remaining 3 cases had insufficient cells. In addition to overall lesser cellularity on MP, fibroadenoma cases had smaller epithelial sheets and absence of stroma compared with CS. Both methods had comparable cellular preservation and diagnostic evaluation time, but background debris and preparation time were greater for MP. CONCLUSION: CS are favored over MP for the preparation of breast FNA specimens in centers with specialized FNA services because of their higher diagnostic yield, ease of preparation, and availability for immediate cytologic evaluation. However, in settings where specimens are collected sporadically by unskilled clinicians, the MP system may prove to be useful as an alternative or an adjunct to CS. Cancer (Cancer Cytopathol)


Asunto(s)
Biopsia con Aguja , Enfermedades de la Mama/patología , Neoplasias de la Mama/patología , Citodiagnóstico/métodos , Femenino , Humanos , Palpación , Coloración y Etiquetado , Factores de Tiempo
8.
Exp Cell Res ; 211(1): 1-5, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8125147

RESUMEN

To determine whether neural crest-derived neuroblastoma cells may release cytokines which regulate the function of leukocytes, we found that neuroblastoma (HTB-11) cells did not constitutionally express IL-1 beta, TNF alpha, or IL-8 mRNA. However, TNF alpha, which induced HTB-11 cells to differentiate to perineurium-like cells, induced expression of IL-8 mRNA in a dose- and time-dependent fashion. In contrast, pentoxifylline (1 mM), which promoted HTB-11 cells to differentiate to polygonal neuron-like cells, did not induce IL-8 mRNA expression. As determined by enzyme-linked immunoassay, high levels of IL-8 were detectable in the culture supernatants from TNF alpha-treated neuroblastoma cells, but not pentoxifylline-treated neuroblastoma cells (19.60 +/- 2.34 vs 0.10 +/- 0.06 ng/ml). Culture supernatants obtained from TNF alpha-treated neuroblastoma cells induced chemotaxis of neutrophils and lymphocytes that was significantly blocked by anti-IL-8 neutralizing antibodies. Detection of a leukocyte chemotactic factor was not observed in the culture supernatants from pentoxifylline-treated cells. These results suggest that neural crest-derived perineurium-like cells, but not neuron-like cells, may release a leukocyte chemotactic factor or factors such as IL-8 which could be involved in leukocyte recruitment seen in inflammatory diseases affecting peripheral nerves.


Asunto(s)
Quimiotaxis de Leucocito/fisiología , Interleucina-8/fisiología , Neuroblastoma/química , Neuroblastoma/patología , Comunicación Celular/fisiología , Diferenciación Celular/fisiología , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Regulación de la Expresión Génica/genética , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Neuroblastoma/fisiopatología , Neutrófilos/citología , Neutrófilos/fisiología , Pentoxifilina/farmacología , ARN Mensajero/análisis , ARN Mensajero/genética , Factores de Tiempo , Células Tumorales Cultivadas , Factor de Necrosis Tumoral alfa/farmacología
9.
Pediatr Res ; 34(6): 720-4, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8108182

RESUMEN

Neuroblastoma cells in response to retinoic acid (RA) exhibit differentiation. RA, which can promote tumor cell differentiation, has also been shown to regulate tumor-infiltrating leukocytes. In an attempt to explore the relationship between RA-induced neuroblastoma cell differentiation and leukocyte chemotaxis, we investigated expression of IL-1 beta, IL-8, granulocyte-macrophage colony stimulating factor, and tumor necrosis factor-alpha in the undifferentiated and RA-induced differentiated neuroblastoma cells. Using SK-N-SH neuroblastoma cells, we found that RA induced differentiation of SK-N-SH cells as demonstrated by down-regulation of N-myc gene expression, cell-cycle arrest in G1 phase, and phenotypic change. Neither RA-treated nor untreated neuroblastoma cells expressed IL-1 beta, granulocyte-macrophage colony stimulating factor, or tumor necrosis factor-alpha mRNA. RA-treated but not untreated SK-N-SH cells expressed IL-8 mRNA in a time- and dose-dependent fashion. As determined by ELISA, IL-8 levels were detectable in the culture supernatants from RA-treated, but not untreated, neuroblastoma cells (2.65 +/- 0.43 versus 0.05 +/- 0.04 ng/mL). Using neutrophil and lymphocyte chemotactic assays, we found that RA-treated but not untreated culture supernatants of neuroblastoma cells promoted neutrophil and lymphocyte chemotaxis. The RA enhancement of neuroblastoma cell-mediated leukocyte chemotaxis was significantly blocked by anti-IL-8 neutralizing antibodies. These results suggest that RA-induced neuroblastoma cell differentiation is associated with production of functional IL-8, which may be involved in the leukocyte infiltration and activation resulting in tumor regression.


Asunto(s)
Quimiotaxis de Leucocito/efectos de los fármacos , Interleucina-8/biosíntesis , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/inmunología , Tretinoina/farmacología , Diferenciación Celular/efectos de los fármacos , Factor Estimulante de Colonias de Granulocitos y Macrófagos/biosíntesis , Humanos , Interleucina-1/biosíntesis , Activación de Linfocitos/efectos de los fármacos , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/patología , Neuroblastoma/patología , Neutrófilos/efectos de los fármacos , Neutrófilos/inmunología , ARN Mensajero/biosíntesis , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/inmunología , Células Tumorales Cultivadas/patología , Factor de Necrosis Tumoral alfa/biosíntesis
10.
J Anal Toxicol ; 17(6): 348-52, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8271781

RESUMEN

Meconium has been reported to be a more suitable specimen than maternal or neonatal urine for detecting fetal exposure to cocaine. In a study comparing various immunoassays with gas chromatography/mass spectrometry (GC/MS), several unexplained discrepancies among the assays were noted. Using methanol extracts of meconium samples, an immunoreactive spot that was more polar than benzoylecgonine was detected by thin-layer chromatography (TLC). An extract of this spot analyzed by GC/MS yielded a fragmentation pattern indicative of an aryl hydroxylated benzoylecgonine. Standards of m-hydroxybenzoylecgonine, o-hydroxybenzoylecgonine, and p-hydroxybenzoylecgonine were synthesized; it was determined that m-hydroxybenzoylecgonine had the same retention time and ion ratios as the TLC immunoreactive spot. Furthermore, m-hydroxybenzoylecgonine proved to be immunoreactive. Ten meconium samples immunoreactive for benzoylecgonine were analyzed by GC/MS. Results before and after hydrolysis with beta-glucuronidase (type IX) showed free m-hydroxybenzoylecgonine comprising 59 to 94% of the total m-hydroxybenzoylecgonine and showed total m-hydroxybenzoylecgonine values ranging from 0.2 to 6.3 times as high as benzoylecgonine. Therefore, m-hydroxybenzoylecgonine appears to be a quantitatively important cocaine metabolite in meconium, which is responsible for a significant portion of the discrepancy between benzoylecgonine concentrations in meconium extracts as measured by immunoassay and GC/MS.


Asunto(s)
Cocaína/análogos & derivados , Meconio/química , Artefactos , Cocaína/análisis , Humanos , Inmunoensayo
11.
J Ocul Pharmacol ; 9(2): 97-108, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8345292

RESUMEN

A series of thiadiazole derivatives of carbonic anhydrase inhibitors were prepared and their physicochemical properties and pharmacological activities such as corneal permeabilities, inhibition of carbonic anhydrase activities were evaluated. The solubilities and pKa values were determined in varied pH of phosphate buffers at 35 degrees C after equilibrium. Intrinsic solubility and pKa value were calculated from the plot of solubility versus the reciprocal of hydrogen ion concentration. The distribution coefficient was determined in the system of octanol/pH 7.65 phosphate buffer. As a result, the sigma (Hammett constant) and pi (hydrophobic substituent constant) values of substituents were found to be correlated to the logarithm of Ka and partition coefficient. Corneal permeabilities of the analogue were determined in a specially designed diffusion cell using excised rabbit cornea, which ranged from 1.32 x 10(-5) (compound II) to 3.48 x 10(-7) cm/sec (compound VI). Compound with high permeability might be expected to be absorbed well after topical administration into the eye. The methodology of pH-stat was used to determine the inhibition of the carbonic anhydrase activity of the analogue. The IC50 values of the analogue around 10(-8) M as determined were less than that of acetazolamide. The results suggest that the analogue had good pharmacological activity. Finally, an equation for quantitative structure-activity relationship was established for the analogue, which is as follows: [formula: see text]


Asunto(s)
Inhibidores de Anhidrasa Carbónica/química , Inhibidores de Anhidrasa Carbónica/farmacocinética , Tiadiazoles/química , Tiadiazoles/farmacocinética , Absorción , Animales , Anhidrasas Carbónicas/metabolismo , Permeabilidad de la Membrana Celular , Córnea/metabolismo , Concentración de Iones de Hidrógeno , Conejos , Solubilidad , Relación Estructura-Actividad
12.
Zhonghua Jie He He Hu Xi Za Zhi ; 14(5): 276-9, 318-9, 1991 Oct.
Artículo en Chino | MEDLINE | ID: mdl-1819379

RESUMEN

The levels of Ca and P in serum and urine, and the renal functions: Ccr. TRCa and TRP were determined in 43 patients with chronic Cor Pulmonale complicated with respiratory insufficiency. The results showed that the level of SCa decreased in 72.1% (31/43) and after correction by serum protein 58.1% (25/43). The SP was normal in 60.5%, (26/43). UCa and UP reduced in 62.8% (27/43) and 88.4% (38/43) respectively.


Asunto(s)
Calcio/metabolismo , Fósforo/metabolismo , Enfermedad Cardiopulmonar/metabolismo , Insuficiencia Respiratoria/metabolismo , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Cardiopulmonar/complicaciones , Insuficiencia Respiratoria/etiología
15.
Biochem J ; 218(3): 923-32, 1984 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-6326751

RESUMEN

Bovine central-nervous-system myelin was found to contain both Ca2+-activated and cyclic AMP-dependent protein kinases. Each enzyme possesses unique solubility and substrate-specificity characteristics. The Ca2+-activated enzyme, like its substrate (basic protein), is probably deeply embedded in the neural membrane, whereas the cyclic AMP-dependent kinase appears to be much less tightly associated with myelin. Treatment of insoluble myelin fraction housing the Ca2+-activated kinase with phospholipase A2 and phospholipases A2 + C causes a decrease in its ability to become activated by Ca2+. This can be countered by phosphatidylserine and phosphatidylethanolamine. Whereas the activity of the Ca2+-activated membrane-associated kinase is inhibited by chlorpromazine, dibucaine, melittin and Triton X-100, it is activated by certain phorbol diesters (4 beta-phorbol 12-myristate 13-acetate, 4 beta-phorbol 12,13-didecanoate, 4 beta-phorbol 12,13-dibenzoate and 4 beta-phorbol 12,13-diacetate), which appear to exert this effect by lowering the concentration of Ca2+ normally required for the activation of this enzyme. Together these results suggest that the activation of the membrane-associated kinase by Ca2+ most probably requires certain lipids, perhaps those already present in the membrane.


Asunto(s)
Vaina de Mielina/enzimología , Proteínas Quinasas/metabolismo , Animales , Sitios de Unión , Calcio/farmacología , Calmodulina/farmacología , Bovinos , AMP Cíclico/farmacología , Activación Enzimática/efectos de los fármacos , Técnicas In Vitro , Ésteres del Forbol/farmacología , Fosfolipasas/farmacología , Fosfolípidos/farmacología , Fosforilación , Inhibidores de Proteínas Quinasas , Solubilidad , Especificidad por Sustrato
16.
Biochem J ; 209(3): 789-95, 1983 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-6307265

RESUMEN

The phosphotransferase system of human central-nervous-system myelin was investigated. Evidence obtained indicated the presence of at least two different phosphotransferase systems (cyclic nucleotide-dependent and -independent) in myelin, which were found to be firmly associated with the membrane. The cyclic AMP-dependent kinase of myelin and white-matter cytosol preferentially phosphorylated certain histone fractions and displayed only modest activity with basic protein as substrate. On the other hand, the cyclic nucleotide-independent system showed specificity toward basic protein. Its activity was not only dependent on Mg2+ but it was greatly enhanced by this bivalent cation. Whereas the cyclic nucleotide-dependent kinase could be extracted with buffers containing Triton X-100, the bivalent cation-regulated kinase resisted solubilization from myelin under these conditions.


Asunto(s)
Encéfalo/enzimología , Péptidos y Proteínas de Señalización Intracelular , Vaina de Mielina/enzimología , Proteínas Quinasas/metabolismo , Proteínas Portadoras/farmacología , Cationes Bivalentes/farmacología , AMP Cíclico/farmacología , Humanos , Técnicas In Vitro , Cinética , Lípidos/farmacología , Octoxinol , Concentración Osmolar , Fosforilación , Polietilenglicoles/farmacología , Solubilidad , Especificidad por Sustrato
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