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1.
Cancers (Basel) ; 13(24)2021 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-34944855

RESUMEN

In the phase II MAJA trial, maintenance therapy with vinflunine resulted in longer progression-free survival compared to best supportive care in advanced urothelial cell carcinoma (aUCC) patients who did not progress after first-line platinum-based chemotherapy. However, despite an initial benefit observed in some patients, unequivocal resistance appears which underlying mechanisms are presently unknown. We have performed gene expression and functional enrichment analyses to shed light on the discovery of these underlying resistance mechanisms. Differential gene expression profile of eight patients with poor outcome and nine with good outcome to vinflunine administered in the MAJA trial were analyzed. RNA was isolated from tumor tissue and gene expression was assessed by microarray. Differential expression was determined with linear models for microarray data. Gene Set Enrichment Analysis (GSEA) was used for the functional classification of the genes. In vitro functional studies were performed using UCC cell lines. Hierarchical clustering showed a differential gene expression pattern between patients with good and poor outcome to vinflunine treatment. GSEA identified epithelial-to-mesenchymal transition (EMT) as the top negatively enriched hallmark in patients with good outcome. In vitro analyses showed that the polyphenol curcumin downregulated EMT markers and sensitized UCC cells to vinflunine. We conclude that EMT mediates resistance to vinflunine and suggest that the reversion of this process could enhance the effect of vinflunine in aUCC patients.

2.
Chronobiol Int ; 38(2): 201-211, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33397171

RESUMEN

Circadian rhythms are an adaptive response of organisms to the environment that enables them to measure time. Circadian rhythms are some of the most studied biological rhythms. Serotonin (5HT) has been proposed as their modulator of circadian rhythms, playing a pivotal role in their establishment. However, 5HT concentrations are altered in insect organisms when they feed on some plant extracts. Insects show a variety of rhythms. The larval stage of the lepidopteran Spodoptera frugiperda is a pest of economically important crops. As a response, plants have developed secondary metabolites, such as azadirachtin, obtained from Azadirachta indica. We assessed the circadian rhythm of 5HT in the brain and digestive tube of larvae of S. frugiperda; furthermore, the effect of A. indica extract on the oscillations was evaluated. 5HT modulates the rhythms of locomotor activity, and if extracts of A. indica alter the concentration of 5HT, it can indirectly alter the rhythms of locomotor activity, as well as peristaltic movements of the intestine. Larvae were exposed to a 12 h:12 h light-dark (LD) photoperiod, and half of them remained for 72 h under constant darkness (DD). Tissue samples were obtained at six different times during a single 24 h period, and the amount of 5HT was quantified by high-performance liquid chromatography (HPLC). Data were statistically compared by a one-way ANOVA followed by a Tukey post hoc test and subjected to Cosinor analysis for assessment of 24 h rhythmicity. The results showed that the A. indica methanolic extract had an effect on the 5HT concentration of the brain and digestive tube of the larvae. In the brain, the 5HT increase in larvae fed with the extract could alter memory, learning, sleep, and locomotor activity processes. Whereas in the intestine, the 5HT decrease in the larvae fed with the extract could decrease peristalsis movements and, therefore, indirectly influence the antifeedant effect.


Asunto(s)
Azadirachta , Meliaceae , Animales , Ritmo Circadiano , Serotonina , Spodoptera
3.
J Sci Food Agric ; 101(2): 548-554, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32673405

RESUMEN

BACKGROUND: Ferulic acid is a natural occurring compound with antioxidant and antimicrobial bioactive properties, and recently was proposed as a new alternative growth promoter in meat-producing animals without changing meat quality parameters. The present study aimed to evaluate the impact of two doses of ferulic acid (FA) on the feedlot performance, carcass traits, and physicochemical and sensory characteristics of meat quality in commercial heifers. Ninety heifers (3/4 Bos taurus; n = 270; body weight = 480 ± 10 kg) were randomly assigned to one of the following treatments (30 days): Control, fed with a basal diet; FA250 or FA500 offered the same diet further supplemented with FA at 250 or 500 mg kg-1 feed, respectively. Feedlot performance, carcass traits, and physicochemical and meat sensory characteristics were evaluated. RESULTS: FA supplementation increased average daily gain (ADG) by 21%, hot carcass weight by 1.8% and cold carcass weight by 1.6% with respect to the control (P < 0.05). FA500 treatment caused a decrease (P < 0.05) in some carcass traits. However, carcass characteristics of economic importance, such as cold carcass dressing and LT muscle area, were improved by FA250 supplementation (P < 0.05), causing a possible growth promoter effect. Physicochemical and sensory parameters of meat were not altered by FA supplementation (P > 0.05). CONCLUSION: Ferulic acid has the potential for use as a growth promoter additive in finishing heifers without negatively affecting the meat quality, as occurs with some synthetic growth promotants compounds used in animal production. © 2020 Society of Chemical Industry.


Asunto(s)
Bovinos/crecimiento & desarrollo , Ácidos Cumáricos/metabolismo , Suplementos Dietéticos/análisis , Carne/análisis , Alimentación Animal/análisis , Animales , Bovinos/metabolismo , Femenino , Humanos , Masculino , Control de Calidad , Gusto
4.
Animals (Basel) ; 10(7)2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-32698311

RESUMEN

The effect of plant extracts (PE; artichoke, celery, beet, onion, garlic, spinach, avocado, oats, and parsley) in the diet of growing pigs under heat stress was investigated. Parameters included growth performance, blood constituents, carcass characteristics, organ percentage, quality and sensory appraisal of the pork. The study was performed during the Mexican summer, using 60 pigs. Treatments included the control, to which 0.1% PE, and 0.15% PE were added. The use of PE (0.1 and 0.15%) generated an increase in the average daily gain (ADG, by 10.0% for both treatments), and final live weight (LW, by 6.3% and 6.8%) (p < 0.05). The level of blood albumin at 95 kg was higher when supplementing with 0.1% PE (p < 0.05). At 120 kg LW, creatine kinase values showed a tendency to be different (p = 0.07). Carcass weight increased (p < 0.05) when adding PE. Supplementation with 0.1% PE decreased (p < 0.05) the red/green (a *) hue of the meat, whereas supplementation with 0.1% and 0.15% PE increased the yellow/blue (b *) hue (p < 0.05). The addition of PE improves pig growth performance, and carcass weight by reducing the negative effects of heat stress, without markedly modifying blood constituents, meat quality, and sensory attributes of the pork.

5.
Meat Sci ; 135: 115-122, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28968554

RESUMEN

The objective of this work was to evaluate the quality of a bologna-type meat product designed for the elderly. Treatments were: control, without addition of cranberries (C), prunes (P), pecan nuts (N) or flaxseed (F); NP, with 5% N+5% P; FC, with 5% F+5% C; NC, with 5% N+5% C; FP, with 5% F+5% P. These formulations resulted in a product with high protein, low SFA and high antioxidant activity. Treatments with pecan nuts had higher MUFA while those with flaxseed had higher polyunsaturated fatty acids (PUFA). Treatments with pecan nuts and flaxseed had higher PUFA/SFA ratios, but only those with flaxseed had very low n6/n3 ratios when compared to the control. Although treatments showed acceptable scores (>5.4), they were lower than the control. A combination of these non-traditional ingredients could be used to develop a meat product for older adults to provide a better nutritional profile with acceptable sensory properties.


Asunto(s)
Grasas de la Dieta/análisis , Productos de la Carne/análisis , Gusto , Anciano , Anciano de 80 o más Años , Animales , Carya , Color , Ácidos Grasos/análisis , Lino , Humanos , Concentración de Iones de Hidrógeno , México , Nueces , Prunus domestica , Sarcopenia/prevención & control , Porcinos , Vaccinium macrocarpon
6.
Nat Genet ; 47(3): 250-6, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25665005

RESUMEN

Resistance to RAF- and MEK-targeted therapy is a major clinical challenge. RAF and MEK inhibitors are initially but only transiently effective in some but not all patients with BRAF gene mutation and are largely ineffective in those with RAS gene mutation because of resistance. Through a genetic screen in BRAF-mutant tumor cells, we show that the Hippo pathway effector YAP (encoded by YAP1) acts as a parallel survival input to promote resistance to RAF and MEK inhibitor therapy. Combined YAP and RAF or MEK inhibition was synthetically lethal not only in several BRAF-mutant tumor types but also in RAS-mutant tumors. Increased YAP in tumors harboring BRAF V600E was a biomarker of worse initial response to RAF and MEK inhibition in patients, establishing the clinical relevance of our findings. Our data identify YAP as a new mechanism of resistance to RAF- and MEK-targeted therapy. The findings unveil the synthetic lethality of combined suppression of YAP and RAF or MEK as a promising strategy to enhance treatment response and patient survival.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Quinasas Quinasa Quinasa PAM/antagonistas & inhibidores , Fosfoproteínas/genética , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Femenino , Técnicas de Silenciamiento del Gen , Genes ras , Células HEK293 , Células HT29 , Xenoinjertos , Vía de Señalización Hippo , Humanos , Quinasas Quinasa Quinasa PAM/genética , Quinasas Quinasa Quinasa PAM/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/genética , Ratones , Ratones Endogámicos NOD , Ratones SCID , Terapia Molecular Dirigida , Mutación , Fosfoproteínas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Factores de Transcripción , Proteínas Señalizadoras YAP
7.
J Antimicrob Chemother ; 52(3): 514-7, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12917251

RESUMEN

OBJECTIVE: This study tests the usefulness of ceftriaxone combined with ampicillin as an alternative to ampicillin plus gentamicin for the treatment of experimental endocarditis due to Enterococcus faecalis without high-level resistance to aminoglycosides. It also determines whether adding ceftriaxone to ampicillin and gentamicin increases the effectiveness against experimental enterococcal endocarditis resulting from E. faecalis. METHODS: Animals with catheter-induced endocarditis were infected intravenously with 108 cfu of the EF91 strain of E. faecalis and were treated for 3 days with ampicillin 2 g every 4 h administered as 'human-like' (H-L) pharmacokinetics, plus gentamicin 1 mg/kg every 8 h H-L, or ceftriaxone 2 g every 12 h H-L alone or combined with gentamicin 6 mg/kg every 24 h administered subcutaneously. RESULTS: The results of therapy for experimental endocarditis resulting from EF91 showed that the combination of ampicillin plus ceftriaxone was as effective as ampicillin plus gentamicin. The triple combination did not improve on the overall efficacies of the two-drug combinations. CONCLUSIONS: Because of its lower nephrotoxicity, ampicillin plus ceftriaxone may be a useful alternative therapy for E. faecalis endocarditis in selected patients.


Asunto(s)
Aminoglicósidos/farmacología , Ampicilina/uso terapéutico , Antibacterianos/uso terapéutico , Ceftriaxona/uso terapéutico , Cefalosporinas/uso terapéutico , Quimioterapia Combinada/uso terapéutico , Endocarditis Bacteriana/tratamiento farmacológico , Enterococcus faecalis/efectos de los fármacos , Gentamicinas/uso terapéutico , Penicilinas/uso terapéutico , Ampicilina/farmacocinética , Animales , Antibacterianos/farmacocinética , Área Bajo la Curva , Ceftriaxona/farmacocinética , Cefalosporinas/farmacocinética , Farmacorresistencia Bacteriana , Sinergismo Farmacológico , Quimioterapia Combinada/farmacocinética , Endocarditis Bacteriana/microbiología , Gentamicinas/farmacocinética , Semivida , Humanos , Pruebas de Sensibilidad Microbiana , Penicilinas/farmacocinética , Conejos
8.
Teratology ; 66(5): 249-56, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12397633

RESUMEN

BACKGROUND: Nuevo León is a state in northeastern Mexico, near the border of Texas. Mean mortality rate from 1996-98 due to anencephaly cases was 0.6/1,000. In 1999 a surveillance program for the registry and prevention of neural tube defects (NTD) cases was initiated. METHODS: Cases were obtained from hospitals and OB-GYN clinics by immediate notification, death certificates, or fetal death registries. Only isolated cases of NTD were included. In August 1999 a folic acid campaign was initiated with the free distribution of the vitamin to low-income women with a recommendation to take a 5.0-mg pill once a week. Number of cases and rates from 1999 to 2001 were compared (chi(2) test). RESULTS: After 2 years there has been a significant reduction in the number of cases and rates. In 1999 there were 95 NTD cases and in the years 2000 and 2001 there were only 59 and 55 respectively (P < 0.001). NTD rate decreased from 1.04/1,000 in 1999 to 0.58/1,000 in 2001. Anencephaly and spina bifida rates decreased from 0.55/1,000 to 0.29/1,000 and from 0.47/1,000 to 0.22/1,000 respectively, from 1999-2001. Decrease of female cases was higher than male cases for both phenotypes. CONCLUSION: After 2 years there was a 50% decrease in the incidence of anencephaly and spina bifida cases with a significant reduction of infant mortality and disability. These results encourage us to propose the use of a single tablet of 5.0-mg of folic acid per week as an alternative to supplementation on a daily basis.


Asunto(s)
Ácido Fólico/uso terapéutico , Defectos del Tubo Neural/epidemiología , Atención Prenatal , Anencefalia/epidemiología , Anencefalia/prevención & control , Suplementos Dietéticos , Encefalocele/epidemiología , Encefalocele/prevención & control , Femenino , Humanos , Masculino , México/epidemiología , Defectos del Tubo Neural/prevención & control , Vigilancia de la Población , Embarazo , Resultado del Embarazo/epidemiología , Prevalencia , Sistema de Registros , Población Rural , Factores Sexuales , Disrafia Espinal/epidemiología , Disrafia Espinal/prevención & control , Población Urbana
9.
Antimicrob Agents Chemother ; 46(2): 378-84, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11796345

RESUMEN

We compared the efficacy of ceftriaxone combined with gentamicin, both given once a day, with that of cloxacillin given every 4 h plus gentamicin given once a day or in three daily doses (t.i.d.) for the treatment of experimental methicillin-susceptible staphylococcal endocarditis. The antibiotics were administered by using human-like (H-L) pharmacokinetics that simulated the profiles of these drugs in human serum. Animals with catheter-induced endocarditis were infected intravenously with 10(5) CFU of Staphylococcus aureus S5 (MICs and minimal bactericidal concentrations of cloxacillin, ceftriaxone, and gentamicin, 0.5 and 2 microg/ml, 4 and 8 microg/ml, and 0.5 and 1 microg/ml, respectively). The animals were then treated for 24 h with cloxacillin at a dose of 2 g that simulated H-L pharmacokinetics (H-L 2 g) every 4 h alone or combined with gentamicin (administered at doses of H-L 1 mg/kg of body weight every 8 h or H-L 4.5 mg/kg every 24 h) or with ceftriaxone at H-L 2 g every 24 h alone or combined with gentamicin (administered at doses of H-L 1 mg/kg every 8 h or H-L 4.5 mg/kg every 24 h). The results of therapy for experimental endocarditis due to the S5 strain showed that (i) cloxacillin alone is more effective than ceftriaxone alone in reducing the bacterial load (P < 0.01), (ii) the combination of cloxacillin or ceftriaxone with gentamicin is more effective than each of these drugs alone (P < 0.01), and (iii) Ceftriaxone H-L plus gentamicin H-L 4.5 mg/kg, both administered every 24 h, showed efficacy similar to that of the "gold standard," cloxacillin H-L plus gentamicin H-L 1 mg/kg t.i.d. (P > 0.05). An increase in the interval of administration of gentamicin to once daily resulted in a reduction in the numbers of bacteria in the vegetations equivalent to that achieved with the recommended regimen of cloxacillin plus gentamicin t.i.d. in the treatment of experimental endocarditis due to methicillin-susceptible S. aureus. Ceftriaxone plus gentamicin, both administered once a day, may be useful for home-based therapy for selected cases of staphylococcal endocarditis.


Asunto(s)
Ceftriaxona/uso terapéutico , Endocarditis Bacteriana/tratamiento farmacológico , Gentamicinas/uso terapéutico , Staphylococcus aureus/efectos de los fármacos , Animales , Antibacterianos/farmacocinética , Antibacterianos/uso terapéutico , Ceftriaxona/farmacocinética , Cefalosporinas/farmacocinética , Cefalosporinas/uso terapéutico , Modelos Animales de Enfermedad , Quimioterapia Combinada , Endocarditis Bacteriana/metabolismo , Gentamicinas/farmacocinética , Pruebas de Sensibilidad Microbiana , Conejos , Resultado del Tratamiento
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