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1.
Ann Oncol ; 31(8): 1030-1039, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32339648

RESUMEN

BACKGROUND: The phase 3 JAVELIN Renal 101 trial (NCT02684006) demonstrated significantly improved progression-free survival (PFS) with first-line avelumab plus axitinib versus sunitinib in advanced renal cell carcinoma (aRCC). We report updated efficacy data from the second interim analysis. PATIENTS AND METHODS: Treatment-naive patients with aRCC were randomized (1 : 1) to receive avelumab (10 mg/kg) intravenously every 2 weeks plus axitinib (5 mg) orally twice daily or sunitinib (50 mg) orally once daily for 4 weeks (6-week cycle). The two independent primary end points were PFS and overall survival (OS) among patients with programmed death ligand 1-positive (PD-L1+) tumors. Key secondary end points were OS and PFS in the overall population. RESULTS: Of 886 patients, 442 were randomized to the avelumab plus axitinib arm and 444 to the sunitinib arm; 270 and 290 had PD-L1+ tumors, respectively. After a minimum follow-up of 13 months (data cut-off 28 January 2019), PFS was significantly longer in the avelumab plus axitinib arm than in the sunitinib arm {PD-L1+ population: hazard ratio (HR) 0.62 [95% confidence interval (CI) 0.490-0.777]}; one-sided P < 0.0001; median 13.8 (95% CI 10.1-20.7) versus 7.0 months (95% CI 5.7-9.6); overall population: HR 0.69 (95% CI 0.574-0.825); one-sided P < 0.0001; median 13.3 (95% CI 11.1-15.3) versus 8.0 months (95% CI 6.7-9.8)]. OS data were immature [PD-L1+ population: HR 0.828 (95% CI 0.596-1.151); one-sided P = 0.1301; overall population: HR 0.796 (95% CI 0.616-1.027); one-sided P = 0.0392]. CONCLUSION: Among patients with previously untreated aRCC, treatment with avelumab plus axitinib continued to result in a statistically significant improvement in PFS versus sunitinib; OS data were still immature. CLINICAL TRIAL NUMBER: NCT02684006.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Anticuerpos Monoclonales Humanizados , Axitinib , Carcinoma de Células Renales/tratamiento farmacológico , Humanos , Neoplasias Renales/tratamiento farmacológico , Sunitinib/uso terapéutico
2.
Eur J Cancer ; 114: 67-75, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31075726

RESUMEN

BACKGROUND: Immune checkpoint inhibitors (ICIs) are being increasingly utilised in the front-line (1L) setting of metastatic clear-cell renal cell carcinoma (mccRCC). Limited data exist on responses and survival on second-line (2L) vascular endothelial growth factor-receptor tyrosine kinase inhibitor (VEGFR-TKI) therapy after 1L ICI therapy. PATIENTS AND METHODS: This is a retrospective study of mccRCC patients treated with 2L VEGFR-TKI after progressive disease (PD) with 1L ICI. Patients were treated at MD Anderson Cancer Center or Memorial Sloan Kettering Cancer Center between December 2015 and February 2018. Objective response was assessed by blinded radiologists' review using Response Evaluation Criteria in Solid Tumours v1.1. Descriptive statistics and Kaplan-Meier method were used. RESULTS: Seventy patients were included in the analysis. Median age at mccRCC diagnosis was 59 years; 8 patients (11%) had international metastatic database consortium favourable-risk disease, 48 (69%) had intermediate-risk disease and 14 (20%) had poor-risk disease. As 1L therapy, 12 patients (17%) received anti-programmed death ligand-1 (PD-(L)1) monotherapy with nivolumab or atezolizumab, 33 (47%) received nivolumab plus ipilimumab and 25 (36%) received combination anti-PD-(L)1 plus bevacizumab. 2L TKI therapies included pazopanib, sunitinib, axitinib and cabozantinib. On 2L TKI therapy, one patient (1.5%) achieved a complete response, 27 patients (39.7%) a partial response and 36 patients (52.9%) stable disease. Median progression-free survival (mPFS) was 13.2 months (95% confidence interval: 10.1, NA). Forty-five percent of subjects required a dose reduction, and twenty-seven percent of patients discontinued treatment because of toxicity. CONCLUSIONS: In this retrospective study of patients with mccRCC receiving 2L TKI monotherapy after 1L ICI, we observed 2L antitumour activity and tolerance comparable to historical data for 1L TKI.


Asunto(s)
Carcinoma de Células Renales/tratamiento farmacológico , Inmunoterapia/métodos , Neoplasias Renales/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Carcinoma de Células Renales/mortalidad , Carcinoma de Células Renales/patología , Femenino , Humanos , Neoplasias Renales/mortalidad , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Inhibidores de Proteínas Quinasas/farmacología , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
4.
Vet Microbiol ; 64(1): 51-60, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9874103

RESUMEN

Mycobacterium avium subsp. paratuberculosis, the cause of Johne's disease in ruminants, cannot be cultured in large quantities from affected sheep in Australia. A method is described for the purification of the organism from the intestinal mucosa of sheep with multibacillary Johne's disease in order to undertake restriction fragment length polymorphism (RFLP) analysis for epidemiological purposes. Using sucrose and potassium chloride as separation media for differential and density gradient centrifugation, yields of approximately 90 mg dry weight M. avium subsp. paratuberculosis per 5 g intestinal mucosa were obtained. The preparations of purified M. avium subsp. paratuberculosis were visually free of non-acid fast bacteria and contained 10(2)-10(3) aerobic/ facultatively anaerobic organisms per gram wet weight. DNA extracted from purified M. avium subsp. paratuberculosis was examined by hybridisation with an IS900 probe after digestion with BstEII and RFLP patterns distinct from isolates from cattle were obtained. The RFLP pattern of purified M. avium subsp. paratuberculosis from five sheep matched that obtained previously from organisms cultured from sheep in studies in New Zealand, indicating that the purification and RFLP method is robust.


Asunto(s)
Mucosa Intestinal/microbiología , Mycobacterium avium subsp. paratuberculosis/aislamiento & purificación , Paratuberculosis/microbiología , Enfermedades de las Ovejas/microbiología , Animales , Australia , Bovinos , Centrifugación por Gradiente de Densidad/veterinaria , ADN Bacteriano/análisis , Electroforesis en Gel de Agar/veterinaria , Mycobacterium avium subsp. paratuberculosis/genética , Paratuberculosis/inmunología , Reacción en Cadena de la Polimerasa/veterinaria , Polimorfismo de Longitud del Fragmento de Restricción , Cloruro de Potasio/química , Ovinos , Enfermedades de las Ovejas/inmunología , Sacarosa/química
5.
J Cell Biol ; 121(4): 855-65, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-7684041

RESUMEN

Trichohyalin is a structural protein that is produced and retained in the cells of the inner root sheath and medulla of the hair follicle. The gene for sheep trichohyalin has been purified and the complete amino acid sequence of trichohyalin determined in an attempt to increase the understanding of the structure and function of this protein in the filamentous network of the hardened inner root sheath cells. Sheep trichohyalin has a molecular weight of 201,172 and is characterized by the presence of a high proportion of glutamate, arginine, glutamine, and leucine residues, together totaling more than 75% of the amino acids. Over 65% of trichohyalin consists of two sets of tandem peptide repeats which are based on two different consensus sequences. Trichohyalin is predicted to form an elongated alpha-helical rod structure but does not contain the sequences required for the formation of intermediate filaments. The amino terminus of trichohyalin contains two EF hand calcium-binding domains indicating that trichohyalin plays more than a structural role within the hair follicle. In situ hybridization studies have shown that trichohyalin is expressed in the epithelia of the tongue, hoof, and rumen as well as in the inner root sheath and medulla of the hair follicle.


Asunto(s)
Calcio/metabolismo , Cabello/metabolismo , Precursores de Proteínas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN , Epitelio/metabolismo , Hibridación in Situ , Proteínas de Filamentos Intermediarios , Queratinas/metabolismo , Datos de Secuencia Molecular , Precursores de Proteínas/aislamiento & purificación , Precursores de Proteínas/metabolismo , Mapeo Restrictivo , Ovinos
6.
J Cell Sci ; 102 ( Pt 2): 353-60, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1400637

RESUMEN

An alpha-D-galactoside-specific lectin from Bandeiraea simplicifolia (BSLI) showed differential binding to cortical cells of the wool follicle bulb. The lectin bound to cells on one side only of the bulb and was completely blocked by alpha-D-galactose. The region of lectin binding extended from presumptive cortical cells at the base of the bulb to cortical cells at the top of the bulb, disappearing as cortical cells entered the fibre cortex. An orthocortex-specific monoclonal antibody was used to show that cortical cells recognised by the lectin lie directly below the fibre orthocortex and presumably give rise to the orthocortex. The results suggest that two distinct populations of presumptive cortical cells are present only two to three cell layers from the base of the bulb in a region where no morphological differences are detectable. The lectin-bound pre-cortical cells appear to give rise to orthocortical cells while cells not bound by lectin presumably give rise to paracortical cells. Electron microscopy showed that the lectin bound to sites on the plasma membrane, probably on the extracellular surface. This suggests that the lectin target may be a membrane glycoprotein or glycolipid. Two polypeptides recognised by BSLI were separated from wool follicle extracts by SDS-gel electrophoresis. These polypeptides migrated at approximately 69 kDa and 17 kDa. However, only the 69 kDa molecule showed the expected loss of binding by BSLI in the presence of alpha-D-galactose. Further work will be required to determine if this glycoprotein is the bulb cell molecule recognised by BSLI.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Lectinas/metabolismo , Lectinas de Plantas , Lana/citología , Animales , Femenino , Microscopía Electrónica , Ovinos , Piel/citología , Piel/metabolismo , Piel/ultraestructura , Lana/metabolismo , Lana/ultraestructura
8.
Exp Cell Res ; 163(2): 453-66, 1986 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3956585

RESUMEN

During growth of the eye lens, epithelial cells differentiate into fibre cells under the influence of neural retina. The fibre differentiation factor (FDF) was partially characterized from calf retina-conditioned medium, using lens epithelial explants from young rats, to provide a bioassay for differentiation. FDF was associated with large-protein aggregates, the smallest of which eluted at approximately 500-600 kD on Sephacryl S-300 columns and migrated as a single protein band near 600 kD on gradient gels. This protein resolved into nine major peptides on SDS-polyacrylamide gels, ranging between 23 and 27 kD. Eight of these peptides were present oa four doublets, but did not appear to contain specific carbohydrate residues. The approximately 500-600 kD complex could be slightly disrupted by trypsin or heat treatment to release a less stable 90 kD component. Fractionation of FDF invariably led to loss of activity, possibly due to gradual dissociation into less active and/or less stable components. A working hypothesis suggested by these findings is that FDF is associated with a small group of peptides, each contributing an essential function to the process of fibre differentiation.


Asunto(s)
Proteínas del Ojo/aislamiento & purificación , Cristalino/citología , Retina/análisis , Células Ganglionares de la Retina/análisis , Animales , Bovinos , Diferenciación Celular , Células Cultivadas , Cristalinas/biosíntesis , Medios de Cultivo , Electroforesis en Gel de Poliacrilamida , Células Epiteliales , Proteínas del Ojo/fisiología , Peso Molecular , Técnicas de Cultivo de Órganos
9.
Aust N Z J Ophthalmol ; 13(2): 103-11, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-4052259

RESUMEN

Lens epithelial explants grown in retina-conditioned medium (RCM) undergo structural and molecular changes characteristic of fibre differentiation in the intact lens. We suggest that in vivo neural retina releases a fibre differentiation factor (FDF) that interacts with equatorial lens epithelial cells and stimulates them to undergo fibre cell differentiation. According to this model, interaction with neural retina is essential for normal lens formation in embryos and for normal lens growth throughout life. Preliminary work on purification of the factor indicates that FDF activity is associated with a high molecular weight complex of 500 kd. The active component of this complex appears to be an 80 kd molecule.


Asunto(s)
Inhibidores de Crecimiento , Interleucina-6 , Cristalino/fisiología , Linfocinas , Retina/fisiología , Animales , Animales Recién Nacidos/fisiología , Diferenciación Celular , Células Cultivadas , Fenómenos Químicos , Química , Cristalinas/metabolismo , Medios de Cultivo , Células Epiteliales , Epitelio/ultraestructura , Glicoproteínas/metabolismo , Cristalino/citología , Cristalino/metabolismo , Cristalino/ultraestructura , Factor Inhibidor de Leucemia , Ratas
10.
Exp Eye Res ; 39(1): 83-94, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6383856

RESUMEN

In the intact rat lens, epithelial cells, which are cuboidal and contain alpha-crystallin, give rise to fibre cells, which are elongated and contain alpha-, beta- and gamma-crystallins. Epithelial explants cultured in medium conditioned by bovine neural retinas (BRCM) showed changes analogous to fibre cell differentiation in vivo. The cells became enlarged and elongated and accumulated beta- and gamma-crystallin as well as alpha-crystallin. Labelling studies with [35S]-methionine showed that sequential changes in the synthesis of all three classes of crystallin occurred during culture in BRCM. After two days, synthesis of alpha-crystallin subunits, particularly alpha A and alpha AINS, increased relative to overall protein synthesis. After four days in culture, synthesis of beta-crystallin subunits, identified as beta B1a, beta B4, beta B5 and possibly beta A2, was detected for the first time and between four and eight days gamma-crystallin synthesis became detectable. The time of onset of gamma-crystallin synthesis seemed to show greater experimental variability than did onset of beta-crystallin synthesis. In explants cultured for 10 days in BRCM approximately 25% of new protein synthesis could be attributed to alpha-, beta- and gamma-crystallins. These events were completely dependent on BRCM, suggesting that neural retina secretes a factor(s) which initiates fibre cell differentiation. This culture system appears to be a suitable one for investigating the control of fibre differentiation in vitro.


Asunto(s)
Extractos Celulares/farmacología , Cristalino/crecimiento & desarrollo , Retina/citología , Extractos de Tejidos/farmacología , Animales , Bovinos , Diferenciación Celular , Células Cultivadas , Cristalinas/biosíntesis , Medios de Cultivo , Electroforesis en Gel de Poliacrilamida , Células Epiteliales , Epitelio/metabolismo , Técnica del Anticuerpo Fluorescente , Cristalino/citología , Cristalino/metabolismo , Fragmentos de Péptidos/análisis , Ratas
11.
Eur J Biochem ; 125(2): 401-6, 1982 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7117241

RESUMEN

A putative precursor of carbamoyl-phosphate synthase was isolated from a microsomal wash fraction and purified by high-pressure liquid chromatography. Autolytic degradation and limited proteolysis were used to characterize the putative precursor of carbamoyl-phosphate synthase and to show its similarity to the processed enzyme. The carbamoyl-phosphate synthase precursor underwent a time-dependent and concentration-dependent conversion into a dimeric or polymeric form. When labelled with 125I and incubated with foetal rat liver mitochondria the precursor was bound to the mitochondria and about 30% of the label was imported into the matrix space. This labelling required the presence of ATP and was time-dependent. Mitoplasts also imported the carbamoyl-phosphate synthase precursor. After import of the precursor, increases in carbamoyl-phosphate synthase activity could be demonstrated in foetal rat liver mitochondria.


Asunto(s)
Carbamoil-Fosfato Sintasa (Amoniaco)/metabolismo , Precursores Enzimáticos/aislamiento & purificación , Ligasas/metabolismo , Mitocondrias Hepáticas/enzimología , Adenosina Trifosfato/farmacología , Animales , Electroforesis en Gel de Poliacrilamida , Feto , Ratas , Ratas Endogámicas , Factores de Tiempo
12.
Biochem J ; 186(2): 617-9, 1980 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-6769435

RESUMEN

In the rat, UDP-glucuronosyltransferase activities towards bilirubin, morphine and testosterone increase markedly after normal or premature birth. This rapid development is superimposed upon a much slower maturation of activity which occurs in utero during the last 2 days of normal gestation and gestation when birth is delayed. Development of all three activities is similar under these different conditions, suggesting a common developmenpal regulatory mechanism.


Asunto(s)
Animales Recién Nacidos/metabolismo , Bilirrubina/farmacología , Glucuronosiltransferasa/metabolismo , Hígado/enzimología , Morfina/farmacología , Testosterona/farmacología , Animales , Femenino , Edad Gestacional , Hígado/efectos de los fármacos , Hígado/embriología , Embarazo , Ratas
13.
Biochem J ; 179(3): 473-7, 1979 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-475763

RESUMEN

1. Bilirubin conjugation in rat liver slices was reassessed by using analysis of ethyl anthranilate azopigments to estimate separately the formation of bilirubin mono- and di-glucuronides. 2. Conjugation in slices resembles the situation in vivo more closely than does microsomal conjugation, in that diglucuronide is formed in appreciable quantity. 3. Both bilirubin mono- and di-glucuronides were present in slices in approximately equal amounts, but the monoglucuronide was the major product found in the incubation medium. 4. These results are discussed in relation to recent theories on the relationship between bilirubin mono- and di-glucuronide formation in vivo.


Asunto(s)
Bilirrubina/análogos & derivados , Hígado/metabolismo , Animales , Bilirrubina/biosíntesis , Bilirrubina/metabolismo , Glucuronatos/biosíntesis , Glucuronatos/metabolismo , Hidrólisis , Técnicas In Vitro , Masculino , Microsomas Hepáticos/metabolismo , Ratas
14.
Biochem J ; 178(2): 443-7, 1979 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-109087

RESUMEN

1. A simple colorimetric assay for UDP-glucuronosyltransferase activities towards phenolic substrates, using Folin & Ciocalteu's phenol reagent, is described. The assay is used to measure rat liver transferase activities towards substrates from a series of 4-alkyl-substituted phenols. 2. Activities towards phenol, 4-methylphenol and 4-ethylphenol develop near-adult values before birth, are precociously stimulated by dexa methasone in utero and are stimulated 3--4-fold by 3-methylcholanthrene in adult liver. These are assigned to a "late-foetal" group of transferase activities. 3. Activities towards 4-n-propylphenol, 4-s-butylphenol and 4-t-butylphenol are negligible in late-foetal liver, developing to near-adult values in the first 4 postnatal days, and are not affected by dexamethasone or 3-methylcholanthrene. They are assigned to a "neonatal" group of transferase activities. 4. Although 4-ethylphenol and 4-n-propylphenol differ only by a single --CH2-- moiety, this is sufficient to change the acceptability of these substrates respectively from the late-foetal to the neonatal group of transferase activities. The change is distinct, with no overlapping of substrate acceptability between the two groups of transferase activities. 5. From consideration of the above and other substrates, the two groups of transferase activities do not distinguish substrates on the basis of their molecular weights or lipophilicity. The distinguishing feature appears to be the specific molecular configurations of the substrates.


Asunto(s)
Glucuronosiltransferasa/metabolismo , Fenoles/metabolismo , Animales , Fenómenos Químicos , Química , Colorimetría , Dexametasona/farmacología , Femenino , Técnicas In Vitro , Hígado/embriología , Hígado/enzimología , Masculino , Metilcolantreno/farmacología , Peso Molecular , Embarazo , Ratas
17.
J Med Chem ; 20(2): 256-62, 1977 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-189032

RESUMEN

A general reaction of glycosyl cyanides with liquid hydrogen sulfide in the presence of 4-dimethylaminopyridine to provide the corresponding glycosylthiocarboxamides is described. These glycosylthiocarboxamides were utilized as the precursors for the synthesis of 2-D-ribofuranosylthiazole-4-carboxamide and 2-beta-D-ribofuranosylthiazole-5-carboxamide (23). The structural modification of 2-beta-D-ribofuranosylthiazole-4-carboxamide (12) into 2-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl)thiazole-4-carboxamide (15), 2-beta-D-ribofuranosylthiazole-4-thiocarboxamide (17), and 2-(5-deoxy-beta-D-ribofuranosyl)thiazole-4-carboxamide (19) is also described. These thiazole nucleosides were tested for in vitro activity against type 1 herpes virus, type 3 parainfluenza virus, and type 13 rhinovirus and an in vivo experiment was run against parainfluenza virus. They were also evaluated as potential inhibitors of purine nucleotide biosynthesis. It was shown that the compounds (12 and 15) which possessed the most significant antiviral activity were also active inhibitors (40-70%) of guanine nucleotide biosynthesis.


Asunto(s)
Antivirales/síntesis química , Ribonucleósidos/síntesis química , Tiazoles/síntesis química , Animales , Carcinoma de Ehrlich/metabolismo , Células Cultivadas , Efecto Citopatogénico Viral/efectos de los fármacos , Femenino , Ratones , Virus de la Parainfluenza 3 Humana/efectos de los fármacos , Infecciones por Paramyxoviridae/tratamiento farmacológico , Nucleótidos de Purina/biosíntesis , Rhinovirus/efectos de los fármacos , Ribavirina/farmacología , Ribonucleósidos/farmacología , Ribonucleósidos/uso terapéutico , Simplexvirus/efectos de los fármacos , Relación Estructura-Actividad , Tiazoles/farmacología , Tiazoles/uso terapéutico
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