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1.
An Acad Bras Cienc ; 93(3): e20190731, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33950135

RESUMEN

The objective of this study was to evaluate high-concentrate diets and two energy sources on intake, performance and meat quality parameters of feedlot Nellore heifers. Twenty-eight heifers (200 ± 22.5 kg BW) were randomly assigned to four treatments in a 2×2 factorial arrangement: two concentrate levels (70 and 80%) and two energy sources (corn and corn germ meal). At the end of day 112, heifers were slaughtered. There was no interaction (P>0.05) of concentrate levels and energy sources for dry matter intake, unlike crude protein (CP) and neutral detergent fiber (NDF) intakes. The concentrate level of 80% and corn, allowed the highest CP (1.17 kg/day) and NDF (4.05 kg/day) intakes. Final BW (P<0.05) and daily gain (P<0.01) were influenced just by energy source. The carcass composition represented by muscle and fat was affected by concentrate level (P<0.05). Treatments affected (P<0.01) carcass fat deposition, global preference and texture of Longissimus muscle (P<0.05). It was concluded that high proportions of concentrate containing corn as energy source provided the best performance in heifers, and that the total replacement of corn with corn germ meal in high-concentrate diets is not recommended for performance Nellore heifers, but provided good sensory quality to the meat.


Asunto(s)
Alimentación Animal , Dieta , Alimentación Animal/análisis , Animales , Bovinos , Dieta/veterinaria , Femenino , Carne , Zea mays
2.
Clin Infect Dis ; 69(8): 1353-1359, 2019 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-30561554

RESUMEN

BACKGROUND: Since their emergence in the Americas, chikungunya (CHIKV) and Zika (ZIKV) viruses co-circulate with dengue virus (DENV), hampering clinical diagnosis. We investigated clinical and epidemiological characteristics of arboviral infections during the introduction and spread of CHIKV and ZIKV through northeastern Brazil. METHODS: Surveillance for arboviral diseases among febrile patients was performed at an emergency health unit of Salvador, Brazil, between September 2014 and July 2016. We interviewed patients to collect data on symptoms, reviewed medical records to obtain the presumptive diagnoses, and performed molecular and serological testing to confirm DENV, CHIKV, ZIKV, or nonspecific flavivirus (FLAV) diagnosis. RESULTS: Of 948 participants, 247 (26.1%) had an acute infection, of which 224 (23.6%) were single infections (DENV, 32 [3.4%]; CHIKV, 159 [16.7%]; ZIKV, 13 [1.4%]; and FLAV, 20 [2.1%]) and 23 (2.4%) coinfections (DENV/CHIKV, 13 [1.4%]; CHIKV/FLAV, 9 [0.9%]; and DENV/ZIKV, 1 [0.1%]). An additional 133 (14.0%) patients had serological evidence for a recent arboviral infection. Patients with ZIKV presented with rash and pruritus (69.2% each) more frequently than those with DENV (37.5% and 31.2%, respectively) and CHIKV (22.9% and 14.7%, respectively) (P < .001 for both comparisons). Conversely, arthralgia was more common in CHIKV (94.9%) and FLAV/CHIKV (100.0%) than in DENV (59.4%) and ZIKV (53.8%) (P < .001). A correct presumptive clinical diagnosis was made for 9%-23% of the confirmed patients. CONCLUSIONS: Arboviral infections are frequent causes of febrile illness. Coinfections are not rare events during periods of intense, concomitant arboviral transmission. Given the challenge to clinically distinguish these infections, there is an urgent need for rapid, point-of-care, multiplex diagnostics.


Asunto(s)
Fiebre Chikungunya/transmisión , Virus Chikungunya/fisiología , Virus del Dengue/fisiología , Dengue/transmisión , Infección por el Virus Zika/transmisión , Virus Zika/fisiología , Adolescente , Adulto , Brasil/epidemiología , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/virología , Coinfección , Dengue/epidemiología , Dengue/virología , Monitoreo Epidemiológico , Femenino , Fiebre , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/virología
3.
Beilstein J Nanotechnol ; 13: 873-881, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36105684

RESUMEN

Zika virus (ZIKV) is a mosquito-borne virus that is phylogenetically close to other medically important flaviviruses with high global public health significance, such as dengue (DENV) and yellow fever (YFV) viruses. Correct diagnosis of a flavivirus infection can be challenging, particularly in world regions where more than one flavivirus co-circulates and YFV vaccination is mandatory. Acid nucleic aptamers are oligonucleotides that bind to a specific target molecule with high affinity and specificity. Because of their unique characteristics, aptamers are promising tools for biosensor development. Aptamers are usually obtained through a procedure called "systematic evolution of ligands by exponential enrichment" (SELEX). In this study, we select an aptamer (termed ZIKV60) by capillary electrophoresis SELEX (CE-SELEX) to the Zika virus non-structural protein 1 (NS1) and counterselection against the NS1 proteins of DENV (serotypes 1, 2, 3, and 4) and YFV. The ZIKV60 dissociation constant (K d) is determined by enzyme-linked oligonucleotide assay (ELONA) and the aptamer specificity is evaluated by quantitative real-time polymerase chain reaction. ZIKV60 shows a high binding affinity to the ZIKV NS1 protein with a K d value of 2.28 ± 0.28 nM. The aptamer presents high specificity for ZIKV NS1 compared to NS1 of DENV and YFV. Furthermore, graphene field-effect transistor devices functionalized with ZIKV60 exhibit an evident identification of NS1 protein diluted in human serum. These results point to the applicability of biosensors based on the ZIKV60 aptamer for the differential diagnosis of the Zika virus.

4.
Int J Infect Dis ; 105: 608-616, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33684559

RESUMEN

OBJECTIVES: To investigate risk factors for persistent arthralgia in patients with chikungunya, and describe its impact on daily activities. METHODS: From September 2014 to July 2016, a surveillance study enrolled patients with acute febrile illness in Salvador, Brazil, and detected those with chikungunya virus infection using IgM enzyme-linked immunosorbent assay or reverse transcriptase polymerase chain reaction. Telephone follow-ups were performed to ascertain the progression of disease. RESULTS: Of 153 followed cases, 65 (42.5%) reported chronic arthralgia that lasted >3 months, and 47 (30.7%) were still symptomatic at the time of the interview (approximately 1.5 years after symptom onset). Limitations in daily activities and mental distress were reported by 93.8% and 61.5% of those with chronic arthralgia, respectively. Female sex [risk ratio (RR) 1.79, 95% confidence interval (CI) 1.95-2.69] and age (RR 1.02 for each 1-year increase, 95% CI 1.01-1.03) were independent risk factors for chronic arthralgia. Chronic arthralgia was not associated with co-infection with dengue virus (RR 0.97, 95% CI 0.48-1.94) or chikungunya viral load at diagnosis (median chikungunya virus RNA of 5.60 and 5.52 log10 copies/µL for those with and without chronic arthralgia, respectively; P = 0.75). CONCLUSIONS: These findings reinforce the high frequency of chronic chikungunya arthralgia, and highlight the substantial disability associated with the persistence of pain. Development of novel strategies to mitigate the transmission of chikungunya virus and to provide long-term medical assistance for patients with chikungunya are needed urgently.


Asunto(s)
Artralgia/epidemiología , Fiebre Chikungunya/epidemiología , Virus Chikungunya/inmunología , Dolor Crónico/epidemiología , Adolescente , Adulto , Artralgia/etiología , Artralgia/virología , Brasil/epidemiología , Fiebre Chikungunya/complicaciones , Fiebre Chikungunya/virología , Virus Chikungunya/genética , Niño , Preescolar , Dolor Crónico/etiología , Dolor Crónico/virología , Estudios de Cohortes , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Factores de Riesgo , Adulto Joven
5.
Tuberculosis (Edinb) ; 115: 108-112, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30948164

RESUMEN

Bacteria belonging to Mycobacterium avium complex are organisms of low pathogenicity that infect immunosuppressed individuals. Infection is treated with an antimicrobial macrolide, Clarithromycin (CAM) or Azitromycin, associated with Ethambutol and Rifabutin during 12 months. Regimen long duration and side effects hinder patient's commitment to treatment favoring emergence of antibiotic resistance. In this present study, we evaluated the activity of JVA, an Isoniazid (INH) derivative, against M. avium 2447, a clinical isolate. We demonstrated that JVA reduces M. avium 2447 growth in macrophages, more efficiently than CAM and INH. In order to explore JVA mechanism of action, we investigated compound properties and performed pH-dependent stability studies. Our results suggest an enhanced ability of JVA to cross biological membranes. Furthermore, we suggest that in acidic conditions of macrophages' phagosomes, where mycobacteria replicate, JVA would be promptly hydrolyzed to INH, delivering the adduct INH-nicotinamide adenine dinucleotide and thus inhibiting M. avium 2447 growth.


Asunto(s)
Antituberculosos/farmacología , Isoniazida/análogos & derivados , Complejo Mycobacterium avium/efectos de los fármacos , Infección por Mycobacterium avium-intracellulare/tratamiento farmacológico , Análisis de Varianza , Animales , Hidrazonas/farmacología , Macrófagos/microbiología , Ratones Endogámicos C57BL , Pruebas de Sensibilidad Microbiana , Complejo Mycobacterium avium/crecimiento & desarrollo
6.
Sci Rep ; 9(1): 19311, 2019 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-31848419

RESUMEN

In this study, we develop a real-time PCR strategy to directly detect and quantify DNA aptamers on functionalized graphene surfaces using a Staphylococcus aureus aptamer (SA20) as demonstration case. We show that real-time PCR allowed aptamer quantification in the range of 0.05 fg to 2.5 ng. Using this quantitative technique, it was possible to determine that graphene functionalization with amino modified SA20 (preceded by a graphene surface modification with thionine) was much more efficient than the process using SA20 with a pyrene modification. We also demonstrated that the functionalization methods investigated were selective to graphene as compared to bare silicon dioxide surfaces. The precise quantification of aptamers immobilized on graphene surface was performed for the first time by molecular biology techniques, introducing a novel methodology of wide application.


Asunto(s)
Aptámeros de Nucleótidos/química , Técnicas Biosensibles , Grafito/química , Reacción en Cadena en Tiempo Real de la Polimerasa , Oro/química , Fenotiazinas/farmacología , Staphylococcus aureus/química , Propiedades de Superficie
7.
Adv Rheumatol ; 59(1): 36, 2019 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-31387635

RESUMEN

BACKGROUND: Complement component 4 (C4) gene copy number (GCN) affects the susceptibility to systemic lupus erythematosus (SLE) in different populations, however the possible phenotype significance remains to be determined. This study aimed to associate C4A, C4B and total C4 GCN and SLE, focusing on the clinical phenotype and disease progression. METHODS: C4, C4A and C4B GCN were determined by real-time PCR in 427 SLE patients and 301 healthy controls, which underwent a detailed clinical evaluation according to a pre-established protocol. RESULTS: The risk of developing SLE was 2.62 times higher in subjects with low total C4 GCN (< 4 copies, OR = 2.62, CI = 1.77 to 3.87, p < 0.001) and 3.59 times higher in subjects with low C4A GCN (< 2 copies; OR = 3.59, CI = 2.15 to 5.99, p < 0.001) compared to those subjects with normal or high GCN of total C4 (≥4) and C4A (≥2), respectively. An increased risk was also observed regarding low C4B GCN, albeit to a lesser degree (OR = 1.46, CI = 1.03 to 2.08, p = 0.03). Furthermore, subjects with low C4A GCN had higher permanent disease damage as assessed by the Systemic Lupus International Collaborating Clinics - Damage Index (SLICC-DI; median = 1.5, 95% CI = 1.2-1.9) than patients with normal or high copy number of C4A (median = 1.0, 95% CI = 0.8-1.1; p = 0.004). There was a negative association between low C4A GCN and serositis (p = 0.02) as well as between low C4B GCN and arthritis (p = 0.02). CONCLUSIONS: This study confirms the association between low C4 GCN and SLE susceptibility, and originally demonstrates an association between low C4A GCN and disease severity.


Asunto(s)
Complemento C4/genética , Dosificación de Gen , Predisposición Genética a la Enfermedad , Adolescente , Adulto , Anciano , Análisis de Varianza , Estudios de Casos y Controles , Complemento C4a/genética , Complemento C4b/genética , Estudios Transversales , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Adulto Joven
8.
Adv Rheumatol ; 59: 36, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1088614

RESUMEN

Abstract Background Complement component 4 (C4) gene copy number (GCN) affects the susceptibility to systemic lupus erythematosus (SLE) in different populations, however the possible phenotype significance remains to be determined. This study aimed to associate C4A , C4B and total C4 GCN and SLE, focusing on the clinical phenotype and disease progression. Methods C4 , C4A and C4B GCN were determined by real-time PCR in 427 SLE patients and 301 healthy controls, which underwent a detailed clinical evaluation according to a pre-established protocol. Results The risk of developing SLE was 2.62 times higher in subjects with low total C4 GCN (< 4 copies, OR = 2.62, CI = 1.77 to 3.87, p < 0.001) and 3.59 times higher in subjects with low C4A GCN (< 2 copies; OR = 3.59, CI = 2.15 to 5.99, p < 0.001) compared to those subjects with normal or high GCN of total C4 (≥4) and C4A (≥2), respectively. An increased risk was also observed regarding low C4B GCN, albeit to a lesser degree (OR = 1.46, CI = 1.03 to 2.08, p = 0.03). Furthermore, subjects with low C4A GCN had higher permanent disease damage as assessed by the Systemic Lupus International Collaborating Clinics - Damage Index (SLICC-DI; median = 1.5, 95% CI = 1.2-1.9) than patients with normal or high copy number of C4A (median = 1.0, 95% CI = 0.8-1.1; p = 0.004). There was a negative association between low C4A GCN and serositis ( p = 0.02) as well as between low C4B GCN and arthritis ( p = 0.02). Conclusions This study confirms the association between low C4 GCN and SLE susceptibility, and originally demonstrates an association between low C4A GCN and disease severity.


Asunto(s)
Humanos , Variaciones en el Número de Copia de ADN , Lupus Eritematoso Sistémico/genética , Complemento C4/análisis , Complemento C4a/análisis , Complemento C4b/análisis
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