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1.
Pediatr Infect Dis J ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39264193

RESUMO

OBJECTIVES: To monitor by the first 24 months of life, children born to mothers with laboratory evidence of chikungunya virus (CHIKV) infection during pregnancy or up to 8 weeks before it, and to describe abnormalities in head circumference (HC), auditory and ophthalmological assessments and neuroimaging tests during the follow-up period. METHOD: This is a observational, descriptive, longitudinal and prospective study of children born to mothers who had a rash and a positive test for CHIKV during pregnancy or up to 8 weeks before it. They were admitted between November 2015 and May 2019 in the outpatient multidisciplinary clinic to investigate acute exanthematous disease. The exposed children were followed up by a multidisciplinary team and underwent periodic measurements of the HC. The Denver II test was applied, in addition to transfontanellar ultrasound (TU) to evaluate neurodevelopmental outcomes during the study period. Ophthalmological and auditory examinations, echocardiography and laboratory tests were also included. RESULTS: We included in the study 27 children vertically exposed to CHIKV. All children had a negative polymerase chain reaction test for the virus collected at the first outpatient visit (mean age of 16.8 days and standard deviation of 8 days). No clinical condition compatible with congenital infection at birth was reported. A change in HC characterized by macrocephaly and mild global delay development was observed in a 1-year-old child whose mother was infected in the peripartum, but with normal TU. Changes in the TU were observed in 2 other children with nonspecific subependymal cystic malformation that was not evident by the cranial computed tomography. The other children monitored showed normal results in the Denver II test, in the HC and TU. No changes were identified on ocular ophthalmoscopy or auditory brainstem response test. Two children had an increase in serum ferritin levels during the first year of life, with the others' inflammatory disease markers normal. CONCLUSIONS: Our study added knowledge about the neurodevelopment of children exposed to CHIKV during pregnancy by a longitudinal and prospective follow-up, throughout their first 24 months of life. We did not observe a negative impact of exposure to the virus on the neurological examination, global developmental test or measurements of the HC of these children.

2.
Transl Anim Sci ; 8: txae015, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38371423

RESUMO

The study investigated the effects of 48-h water and feed deprivation on blood and the performance of grazing Nellore (Bos indicus) heifers. Twenty-four Nellore heifers (initial body weight [BW] = 238 ±â€…10 kg; age = 16 ±â€…2 mo), were ranked by initial BW and age and randomly assigned to one of the two treatments: (1) grazing animals with free access to pasture, water, and mineral-mix (CON; n = 12), or (2) the same grazing conditions but deprived of pasture, water, and mineral-mix for 48 h (DPR; n = 12). The paddocks consisted of Urochloa brizantha cv. Marandu, using a continuous and fixed stocking rate. The experiment lasted 225 d, with the first 14 d considered as the adaptation period (days -14 to -1) and the subsequent 211 d as the evaluation period (days 0 to 211). From days 0 to 2, treatments were applied by keeping the DPR heifers in pens and reintegrating them into the experimental area after a 48-h water and feed deprivation. Individual full BW was recorded on days -14, -13, -1, before (day 0) and after (day 2) treatment application, and on days 6, 11, 12, 41, 42, 210, and 211. Blood samples were collected in the morning on days 0, 2, 6, 12, and 211. A treatment effect was detected (P < 0.001) for shrink BW from days 0 to 2, which was greater (P < 0.001) in DPR vs. CON heifers. Subsequently, DPR animals were lighter (P < 0.001) compared with CON heifers by the end of the deprivation period (day 2). From days 4 to 211, DPR was lighter (P < 0.001) compared with CON heifers after treatment application and for the entire experimental period. In the first 10 d after treatment application (days 2 to 12), DPR heifers showed a partial compensatory average daily gain (ADG; P < 0.001) compared with CON heifers, while no significant differences were observed in ADG between the treatments from days 12 to 42 and 42 to 211 (P > 0.420). Overall ADG (days 2 to 211) was greater (P < 0.001) for DPR vs. CON heifers. All serum variables, except AST, were higher (P < 0.001) in DPR than in CON heifers on day 2 after treatment application. Our study demonstrates that grazing Nellore heifers subjected to 48-h water and feed deprivation experienced significant alterations in their blood metabolites and BW immediately after the stressful event. Although the deprived heifers partially compensated for their BW loss in the early days post-deprivation, they remained 12 kg lighter than the non-deprived animals throughout the production cycle.

3.
Immunol Res ; 72(4): 864-873, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38834764

RESUMO

Ataxia-telangiectasia (AT) is a rare genetic disorder leading to neurological defects, telangiectasias, and immunodeficiency. We aimed to study the clinical and immunological features of Latin American patients with AT and analyze factors associated with mortality. Referral centers from 9 Latin American countries participated in this retrospective cohort study, and 218 patients were included. Median (IQR) ages at symptom onset and diagnosis were 1.0 (1.0-2.0)  and 5.0 (3.0-8.0) years, respectively. Most patients presented recurrent airway infections, which was significantly associated with IgA deficiency. IgA deficiency was observed in 60.8% of patients and IgG deficiency in 28.6%. T- and B-lymphopenias were also present in most cases. Mean survival was 24.2 years, and Kaplan-Meier 20-year-survival rate was 52.6%, with higher mortality associated with female gender and low IgG levels. These findings suggest that immunologic status should be investigated in all patients with AT.


Assuntos
Ataxia Telangiectasia , Humanos , Feminino , Masculino , América Latina/epidemiologia , Ataxia Telangiectasia/mortalidade , Ataxia Telangiectasia/imunologia , Ataxia Telangiectasia/diagnóstico , Estudos Retrospectivos , Criança , Pré-Escolar , Adulto , Adolescente , Lactente , Síndromes de Imunodeficiência/mortalidade , Síndromes de Imunodeficiência/epidemiologia , Síndromes de Imunodeficiência/imunologia , Adulto Jovem
4.
Can J Microbiol ; 59(4): 221-30, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23586745

RESUMO

The microbiota associated with coffee plants may play a critical role in the final expression of coffee quality. However, the microbial diversity in coffee cherries is still poorly characterized. Here, we investigated the endophytic diversity in cherries of Coffea arabica by using culture-independent approaches to identify the associated microbes, ultimately to better understand their ecology and potential role in determining coffee quality. Group-specific 16S rRNA and 26S rRNA genes polymerase chain reaction - denaturing gradient gel electrophoresis and clone library sequencing showed that the endophytic community is composed of members of the 3 domains of life. Bacterial sequences showing high similarity with cultured and uncultured bacteria belonged to the Betaproteobacteria, Gammaproteobacteria, and Firmicutes phyla. Phylogenetic analyses of cloned sequences from Firmicutes revealed that most sequences fell into 3 major genera: Bacillus, Staphylococcus, and Paenibacillus. Archaeal sequences revealed the presence of operational taxonomic units belonging to Euryarchaeota and Crenarchaeota phyla. Sequences from endophytic yeast were not recovered, but various distinct sequences showing high identity with filamentous fungi were found. There was no obvious correlation between the microbial composition and cultivar or geographic location of the coffee plant. To the best of our knowledge, this is the first report demonstrating internal tissue colonization of plant fruits by members of the Archaea domain. The finding of archaeal small-subunit rRNA in coffee cherries, although not sufficient to indicate their role as active endophytes, certainly expands our perspectives toward considering members of this domain as potential endophytic microbes.


Assuntos
Archaea/classificação , Bactérias/classificação , Coffea/microbiologia , Archaea/genética , Bactérias/genética , Brasil , Eletroforese em Gel de Gradiente Desnaturante , Fungos/genética , Biblioteca Gênica , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética
5.
Talanta ; 252: 123819, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35973345

RESUMO

Initially, a printed electrode was fabricated in a paper substrate using carbon nanotube ink, graphite pencil and silver nanoparticle ink. For that the electrode was modified with gold nanoparticles and a molecularly imprintedpolymer (MIP) using CA 15-3 as target molecule. The Atomic Force Microscopy (AFM) images exhibited the change in the morphology after each electrode modification. The roughness increasedafter the electropolymerization, and decreased after the extraction procedure. Next, slightly increased again associated to the interaction of CA 15-3 and the imprinted sites. Finally, the Fourier Transform Infrared Spectroscopy (FTIR) results suggested the extraction/rebinding of CA 15-3 in the MIP sensor and also indicated that the NIP sample do not have specific cavities for the CA 15-3. In short, under optimized conditions, the CNE/AuNP is incubated with CA 15-3 (40 U mL-1) for 2 h at 4 °C. Then the electropolymerization was carried out in the potential range of -0.2 to 1.0 V during 20 cycles at scan rate of 50 mV s-1 using a solution containing 15 mM of oPD. After electropolymerization, the sensor was washed with oxalic acid solution for 2 h, leading to the formation of imprinted cavities. The rebinding process was subsequently constructed for 1 h at 4 °C using CA 15-3 solution. The reproducibility and interference studies showed that the sensor can be reproducible and specific for CA 15-3. Then the sensor was applied in determination of CA 15-3 in samples of serum and saliva. The use in serum presented good recovery, but the application in saliva was not satisfactory. Therefore, the sensor CNE/AuNP/MIP could be used in the determination of CA 15-3 in serum samples.


Assuntos
Neoplasias da Mama , Nanopartículas Metálicas , Impressão Molecular , Humanos , Feminino , Ouro/química , Impressão Molecular/métodos , Nanopartículas Metálicas/química , Biomarcadores Tumorais , Reprodutibilidade dos Testes , Polímeros/química , Prata , Neoplasias da Mama/diagnóstico , Eletrodos , Técnicas Eletroquímicas/métodos , Limite de Detecção
6.
Front Vet Sci ; 10: 1117639, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37187926

RESUMO

The objective of this study was to evaluate the effects of different combinations of monensin and narasin on finishing cattle. In Exp. 1, 40 rumen-cannulated Nellore steers [initial body weight (BW) = 231 ± 3.64 kg] were blocked by initial BW and assigned to one of the five treatments as follows: Control (CON): no feed additive in the basal diet during the entire feeding period; Sodium monensin (MM) at 25 mg/kg dry matter (DM) during the entire feeding period [adaptation (days 1-21) and finishing (days 22-42) periods]; Narasin (NN) at 13 mg/kg DM during the entire feeding period (adaptation and finishing periods); Sodium monensin at 25 mg/kg DM during the adaptation period and narasin at 13 mg/kg DM during the finishing period (MN); and narasin at 13 mg/kg DM during the adaptation period and sodium monensin at 25 mg/kg DM during the finishing period (NM). Steers fed MM had lower dry matter intake (DMI) during the adaptation period compared to NM (P = 0.02) but not compared to CON, MM, MN, or NN (P ≥ 0.12). No differences in DMI were observed among the treatments during the finishing (P = 0.45) or the total feeding period (P = 0.15). Treatments did not affect the nutrient intake (P ≥ 0.51) or the total apparent digestibility of nutrients (P ≥ 0.22). In Exp. 2, 120 Nellore bulls (initial BW = 425 ± 5.4 kg) were used to evaluate the effects of the same treatments of Exp. 1 on growth performance and carcass characteristics of finishing feedlot cattle. Steers fed NM had greater DMI during the adaptation period compared to CON, MM, and MN (P ≤ 0.03), but no differences were observed between NM and NN (P = 0.66) or between CON, MM, and NN (P ≥ 0.11). No other differences between treatments were observed (P ≥ 12). Feeding narasin at 13 mg/kg DM during the adaptation period increases the DMI compared to monensin at 25 mg/kg DM, but the feed additives evaluated herein did not affect the total tract apparent digestibility of nutrients, growth performance, or carcass characteristics of finishing cattle.

7.
Biodegradation ; 22(3): 585-92, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21053055

RESUMO

This work aimed at evaluating the biodegradability of different bacterial surfactants in liquid medium and in soil microcosms. The biodegradability of biosurfactants by pure and mixed bacterial cultures was evaluated through CO(2) evolution. Three bacterial strains, Acinetobacter baumanni LBBMA ES11, Acinetobacter haemolyticus LBBMA 53 and Pseudomonas sp. LBBMA 101B, used the biosurfactants produced by Bacillus sp. LBBMA 111A (mixed lipopeptide), Bacillus subtilis LBBMA 155 (lipopeptide), Flavobacterium sp. LBBMA 168 (mixture of flavolipids), Dietzia Maris LBBMA 191(glycolipid) and Arthrobacter oxydans LBBMA 201(lipopeptide) as carbon sources in minimal medium. The synthetic surfactant sodium dodecyl sulfate (SDS) was also mineralized by these microorganisms, but at a lower rate. CO(2) emitted by a mixed bacterial culture in soil microcosms with biosurfactants was higher than in the microcosm containing SDS. Biosurfactant mineralization in soil was confirmed by the increase in surface tension of the soil aqueous extracts after incubation with the mixed bacterial culture. It can be concluded that, in terms of biodegradability and environmental security, these compounds are more suitable for applications in remediation technologies in comparison to synthetic surfactants. However, more information is needed on structure of biosurfactants, their interaction with soil and contaminants and scale up and cost for biosurfactant production.


Assuntos
Bactérias/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Tensoativos/metabolismo , Biodegradação Ambiental , Solo/química
8.
Biodegradation ; 22(5): 1007-15, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21416334

RESUMO

Surfactants and inorganic ligands are pointed as efficient to simultaneous removal of heavy metals and hydrophobic organic pollutants from soil. However, the biosurfactants are potentially less toxic to soil organisms than other chemical agents. Thus, in this study the efficiency of combinations of iodide (I(-)) ligand and surfactants produced by different bacterial species in the simultaneous removal of cadmium (Cd(2+)) and phenanthrene in a Haplustox soil sample was investigated. Four microbial surfactants and the synthetic surfactant Triton X-100 were tested with different concentrations of ligand. Soil samples contaminated with Cd(2+) and phenanthrene underwent consecutive washings with a surfactant/ligand solution. The removal of Cd(2+) increased with increased ligand concentration, particularly in solutions containing biosurfactants produced by the bacterial strains Bacillus subtilis LBBMA155 (lipopeptide) and Flavobacterium sp. LBBMA168 (mixture of flavolipids) and Triton X-100. Maximum Cd(2+) removal efficiency was 99.2% for biosurfactant produced by Arthrobacter oxydans LBBMA 201 (lipopeptide) and 99.2% for biosurfactant produced by Bacillus sp. LBBMA111A (mixed lipopeptide) in the presence of 0.336 mol iodide l(-1), while the maximum efficiency of Triton X-100 removal was 65.0%. The biosurfactant solutions removed from 80 to 88.0% of phenanthrene in soil, and the removal was not influenced by the presence of the ligand. Triton X-100 removed from 73 to 88% of the phenanthrene and, differently from the biosurfactants, iodide influenced the removal efficiency. The results indicate that the use of a single washing agent, called surfactant-ligand, affords simultaneous removal of organic contaminants and heavy metals.


Assuntos
Bacillus subtilis/metabolismo , Cádmio/metabolismo , Recuperação e Remediação Ambiental/métodos , Flavobacterium/metabolismo , Fenantrenos/metabolismo , Poluentes do Solo/metabolismo , Tensoativos/química , Biodegradação Ambiental , Iodetos/química , Octoxinol/química , Microbiologia do Solo
9.
Artigo em Inglês | MEDLINE | ID: mdl-34199255

RESUMO

Sport for children and adolescents must consider growth and maturation to ensure suitable training and competition, and anthropometric variables could be used as bio-banding strategies in youth sport. This investigation aimed to analyze the association between chronological age, biologic maturation, and anthropometric characteristics to explain physical performance of young judo athletes. Sixty-seven judokas (11.0-14.7 years) were assessed for anthropometric and physical performance. Predicted adult stature was used as a somatic maturation indicator. A Pearson's bivariate correlation was performed to define which anthropometric variables were associated with each physical test. A multiple linear hierarchical regression was conducted to verify the effects of age, maturity, and anthropometry on physical performance. The regression models were built with age, predicted adult stature, and the three most significantly correlated anthropometric variables for each physical test. Older judokas performed better in most of the physical tests. However, maturation attenuated the age effect in most variables and significantly affected upper body and handgrip strength. Anthropometric variables attenuated age and maturity and those associated with body composition significantly affected the performance in most tests, suggesting a potential as bio-banding strategies. Future studies should investigate the role of anthropometric variables on the maturity effect in young judokas.


Assuntos
Força da Mão , Artes Marciais , Adolescente , Antropometria , Atletas , Criança , Humanos , Masculino , Desempenho Físico Funcional
10.
EClinicalMedicine ; 38: 101036, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34308302

RESUMO

Background: Vaccination against COVID-19 in Brazil started in January 2021, with health workers and the elderly as the priority groups. We assessed whether there was an impact of vaccinations on the mortality of elderly individuals in a context of wide transmission of the SARS-CoV-2 gamma (P.1) variant. Methods: By May 15, 2021, 238,414 COVID-19 deaths had been reported to the Brazilian Mortality Information System. Denominators for mortality rates were calculated by correcting population estimates for all-cause deaths reported in 2020. Proportionate mortality at ages 70-79 and 80+ years relative to deaths at all ages were calculated for deaths due to COVID-19 and to other causes, as were COVID-19 mortality rate ratios relative to individuals aged 0-69 years. Vaccine coverage data were obtained from the Ministry of Health. All results were tabulated by epidemiological weeks 1-19, 2021. Findings: The proportion of all COVID-19 deaths at ages 80+ years was over 25% in weeks 1-6 and declined rapidly to 12.4% in week 19, whereas proportionate COVID-19 mortality for individuals aged 70-79 years started to decline by week 15. Trends in proportionate mortality due to other causes remained stable. Mortality rates were over 13 times higher in the 80+ years age group compared to that of 0-69 year olds up to week 6, and declined to 5.0 times in week 19. Vaccination coverage (first dose) of 90% was reached by week 9 for individuals aged 80+ years and by week 13 for those aged 70-79 years. Coronavac accounted for 65.4% and AstraZeneca for 29.8% of all doses administered in weeks 1-4, compared to 36.5% and 53.3% in weeks 15-19, respectively. Interpretation: Rapid scaling up of vaccination coverage among elderly Brazilians was associated with important declines in relative mortality compared to younger individuals, in a setting where the gamma variant predominates. Had mortality rates among the elderly remained proportionate to what was observed up to week 6, an estimated additional 43,802 COVID-related deaths would have been expected up to week 19. Funding: CGV and AJDB are funded by the Todos pela Saúde (São Paulo, Brazil) initiative.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31948074

RESUMO

Young judo athletes are bio-banding based on age and body mass and compete in weight classes. The purposes of this study were to investigate the influences of maturation on physical performance in young judokas through controlling the chronological age and body mass, and to examine the mediating role of anthropometric variables. Sixty-seven judokas, aged 11.0-14.7, were measured for 11 anthropometric and seven physical performance variables. Pearson partial correlations were conducted to verify the relationship between the maturational indicator and the dependent variables. Mediation analyses were performed to identify the extent to which anthropometric variables mediate the relationship. The maturation effect remained on the aerobic capacity and handgrip strength (p < 0.05). Fat mass (b = 80.335, 95%CI 11.580-204.270) and fat-free mass (b = 108.256, 95%CI 39.508-207.606) totally mediated the effect on aerobic capacity. Fat mass (b = 0.023, 95%CI 0.004-0.057), fat-free mass (b = 0.029, 95%CI 0.011-0.058), stature (b = 0.031, 95%CI 0.008-0.061), arm span (b = 0.021, 95%CI 0.003-0.044), and inferior members length (b = 0.022, 95%CI 0.005-0.049) totally mediated the effect on handgrip strength. The effect of biological maturation is noticeable even after age and body mass control, being mediated by anthropometric variables related to body composition and size.


Assuntos
Desenvolvimento do Adolescente , Antropometria , Atletas/estatística & dados numéricos , Artes Marciais/fisiologia , Adolescente , Composição Corporal , Estatura , Peso Corporal , Criança , Força da Mão , Humanos , Masculino , Artes Marciais/normas
12.
Transl Anim Sci ; 4(2): txaa030, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32705028

RESUMO

The changes promoted by feed additives in ruminal fermentation, especially increasing the availability of propionate, can improve the energy balance of an animal, which is of great importance in the lactation period. This trial aimed to evaluate the inclusion of narasin in the diet of lactating ewes on milk yield, composition, dry matter intake (DMI), and plasma metabolites of the ewes and growth rate of lambs. Thirty-two lactating ewes (59.0 ± 2.42 kg) were assigned to a randomized complete block design. The experimental diets contained 500 g/kg of dry matter (DM) of coast cross (Cynodon dactylon (L.) Pers) hay and 500 g/kg DM of concentrate, and the treatments were: N0-no narasin inclusion; N13-inclusion of 13 mg of narasin/kg DM. Once a week, from week 2 to 10 of lactation, ewes were separated from their lambs, injected with oxytocin, and milked mechanically to empty the udder. After 3 h, the milk production was recorded, using the same procedure, and sampled to evaluate the composition. The blood samples were taken weekly, 4 h after feeding. The average daily gain (ADG) and starter DMI of the lambs were evaluated weekly from week 2 to 12 of age. The inclusion of narasin did not affect (P = 0.93) DMI of ewes; however, it increased milk production (P < 0.01) and feed efficiency (P = 0.02; FE). Ewes fed N13 had a greater milk fat (P < 0.01), protein (P < 0.01), lactose (P = 0.04), and total solids production (P < 0.01). Narasin inclusion in ewe's diet increased plasma glucose concentration (P = 0.05) at weeks 8, 9 and 10; however, there was no effect on plasma urea concentration (P = 0.96). The lambs of N0 ewes had a greater starter DMI (P < 0.01) at weeks 7, 8, 9, and 10; however, the ADG and body weight at weaning and after weaning were similar between treatments (P > 0.05). The results showed that the inclusion of 13 mg of narasin/kg DM improved the milk production and FE of the ewes without altering the composition of the milk. The lower initial consumption of concentrate by N13 lambs before weaning was caused by the higher production of milk. The results obtained in the present study demonstrate the possible productive gain with the inclusion of narasin in diets for lactating ewes.

13.
Phys Chem Chem Phys ; 11(41): 9583-91, 2009 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-19830345

RESUMO

With the aim of obtaining materials with properties for use as catalysts, two new trimetallic oxides containing Co or Ni and Mo and W were synthesized by a hydrothermal method, using milder conditions than those normally used for wolframite type solids. They were characterized by X-ray diffraction, Fourier transformed infrared spectroscopy, laser Raman spectroscopy, temperature-programmed reduction and atomic absorption spectroscopy, indicating that pure wolframite phases were formed. The X-ray diffraction studies confirmed the formation of the structure in the monoclinic system with cell parameters similar to nickel tungsten wolframite. The laser Raman and infrared spectra showed differences among the samples, mainly due to the incorporation of molybdenum atoms in the wolframite structure. Incorporation of molybdenum in the catalysts improved catalytic activity for propane oxidative dehydrogenation, and lower reaction temperatures were required in order to obtain similar propene yields as in bimetallic tungsten wolframites.

14.
J Phys Chem B ; 110(32): 15803-11, 2006 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-16898729

RESUMO

Carburized molybdenum catalysts supported on a dealuminated NaH-Y zeolite were prepared by carburization under a 20% methane in hydrogen flow of two precursors obtained by adsorption of molybdenum hexacarbonyl, one containing 5 wt % and the other 10 wt % Mo, and a third one was prepared by impregnation with aqueous ammonium heptamolybdate, containing 5 wt % Mo. The three catalysts displayed very distinct behaviors in the benzene hydrogenation reaction at atmospheric pressure and 363 K. By using XANES spectroscopy at the molybdenum L edge, EXAFS and XANES spectroscopy at the molybdenum K edge, and 27Al solid-state NMR spectroscopy, it was shown that different carburized molybdenum species exist in each sample. In the catalyst containing 10 wt % Mo, formation of molybdenum carbide nanoparticles was observed, with an estimated diameter of 1.8 nm. In the catalyst containing 5 wt % Mo and prepared by carburization of adsorbed molybdenum hexacarbonyl, formation of molybdenum oxycarbide dimers is proposed. In the latter case, density functional theory calculations have led to a dimer structure which is compatible with EXAFS results. In the catalyst prepared by impregnation with ammonium heptamolybdate solution followed by carburization, the molybdenum seems to interact with extraframework alumina to produce highly disordered mixed molybdenum-aluminum oxycarbides.


Assuntos
Alumínio/química , Benzeno/química , Compostos Inorgânicos de Carbono/química , Modelos Químicos , Molibdênio/química , Zeolitas/química , Catálise , Hidrogenação , Espectroscopia de Ressonância Magnética/métodos , Teoria Quântica , Sensibilidade e Especificidade , Análise Espectral/métodos , Raios X
15.
Cancer Res ; 60(1): 28-34, 2000 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-10646846

RESUMO

Using Northern blotting, the expression levels of the genes for polyamine metabolism regulatory proteins and clusterin have been measured in a series of 23 human prostate cancers (CaPs) dissected from radical prostatectomy specimens. Patient matched, nontumor tissue was dissected from benign areas of the gland. The results indicate that transcripts encoding ornithine decarboxylase (ODC), ODC antizyme, adenosylmethionine decarboxylase, and spermidine/spermine N1-acetyltransferase (SSAT) were significantly higher, whereas clusterin (sulfated glycoprotein 2) mRNA was significantly lower in tumors compared with the benign tissue. All mRNA levels were compared with those of histone H3 and growth arrest-specific gene 1, markers of cell proliferation and cell quiescence, respectively, and glyceraldehyde 3-phosphate dehydrogenase, a housekeeping gene. In poorly differentiated and locally invasive CaPs and in tumors with unfavorable prognosis or total prostate-specific antigen (PSA) levels > 10.0 ng/ml at diagnosis, an overall increase in the levels of H3 mRNA and a decrease in growth arrest-specific gene 1 mRNA was detected, indicative of higher proliferation activity, whereas the differences in expression levels for the polyamine metabolism and clusterin genes were higher. ODC and SSAT changes were positively correlated in normal tissue but not in high-grade cancer, whereas ODC antizyme and SSAT changes were positively correlated in more malignant CaPs but not in normal tissue. Tumor classification based on the changes in expression levels of all of the genes studied could be correlated to differentiation grade and local invasiveness classification systems in 72.2 and 83.3% of the cases, respectively. In a 1-year follow-up period, three patients whose CaPs ranked as less aggressive according to clinical staging, but classified as advanced cancers with the proposed molecular classification, showed increases in total PSA levels, indicative of tumor relapse. Thus, molecular classification, based on gene expression, may enhance the available prognostic tools for prostate tumors.


Assuntos
Genes Reguladores/fisiologia , Glicoproteínas/metabolismo , Chaperonas Moleculares , Proteínas de Neoplasias/metabolismo , Poliaminas/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Proteínas de Saccharomyces cerevisiae , Acetiltransferases/metabolismo , Adenosilmetionina Descarboxilase/metabolismo , Proteínas de Ciclo Celular , Divisão Celular , Clusterina , Progressão da Doença , Proteínas Ligadas por GPI , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Humanos , Masculino , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana , Ornitina Descarboxilase/metabolismo , Prognóstico , Neoplasias da Próstata/patologia , Proteínas/metabolismo , RNA Mensageiro/metabolismo
16.
Allergy Asthma Clin Immunol ; 2(1): 3-10, 2006 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20529214

RESUMO

The objective of this study was to investigate the prevalence and severity of asthma, rhinitis, and atopic eczema in schoolchildren from southern Brazil. A cross-sectional study was carried out with the International Study of Asthma and Allergies in Childhood phase III written questionnaire. The questionnaire was self-applied by 2,948 randomly selected schoolchildren aged 13 to 14 years. The lifetime prevalence rates of symptoms were as follows: wheezing, 40.8%; rhinitis, 40.7%; eczema, 13.6%; self-reported asthma, 14.6%; rhinitis, 31.4%; eczema, 13.4%. Rhinitis was reported by 55% of adolescents with current asthma (60% females vs 46.9% males). Girls 13 to 14 years of age had higher prevalence rates of asthma, rhinitis, and eczema than boys had. Atopic eczema was reported by 42.7% of girls and 31.4% of boys with asthma. The prevalence rates were statistically significant for symptoms of asthma, rhinitis, and atopic eczema in females. However, there were no statistically significant differences between the sexes in regard to reported asthma and bronchospasm induced by exercise.

17.
J Pediatr (Rio J) ; 92(5): 528-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27237088

RESUMO

OBJECTIVE: To verify if the connection of electrodes for heart and transcutaneous oxygen monitoring interfere with the measurement of electrical bioimpedance in preterm newborns. METHODS: This was a prospective, blinded, controlled, cross-sectional, crossover study that assessed and compared paired measures of resistance (R) and reactance (Xc) by BIA, obtained with and without monitoring wires attached to the preterm newborn. The measurements were performed in immediate sequence, after randomization to the presence or absence of electrodes. The sample size calculated was 114 measurements or tests with monitoring wires and 114 without monitoring wires, considering for a difference between the averages of 0.1 ohms, with an alpha error of 10% and beta error of 20%, with significance <0.05. RESULTS: No differences were observed between the R (677.37±196.07 vs. 677.46±194.86) and Xc (31.15±9.36 vs. 31.01±9.56) values obtained with and without monitoring wires, respectively, with good correlation between them (R: 0.997 and Xc: 0.968). CONCLUSION: The presence of heart and/or transcutaneous oxygen monitoring wires connected to the preterm newborn did not affect the values of R or Xc measured by BIA, allowing them to be carried out in this population without risks.


Assuntos
Monitorização Transcutânea dos Gases Sanguíneos , Impedância Elétrica , Monitorização Fisiológica , Monitorização Transcutânea dos Gases Sanguíneos/instrumentação , Estudos Cross-Over , Estudos Transversais , Eletrodos , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Método Simples-Cego
18.
Eur J Cancer Prev ; 24(3): 245-52, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25121973

RESUMO

Childhood leukemia etiology, and mainly the interactions of genetic and environmental risk factors, remains largely unexplored. This national hospital-based case-control study was carried out in Brazil among children aged 0-23 months who were recruited at cancer and general hospitals in 13 states. Maternal medicine intake during pregnancy, including analgesic intake, was assessed by face-to-face interviews with the mothers of 231 leukemia patients and 411 controls. Unconditional logistic regression was used to ascertain crude and adjusted odds ratios (ORs), and their 95% confidence intervals (CIs) for the association between maternal analgesic use during pregnancy and early age leukemia. Acetaminophen use during the first trimester of pregnancy showed an OR=0.39 (95% CI 0.17-0.93) for acute lymphocytic leukemia and an OR=0.37 (95% CI 0.16-0.88) for use in the second trimester. For acute myeloid leukemia, an OR=0.11 (95% CI 0.02-0.97) was found following acetaminophen use in the second trimester. For acute lymphocytic leukemia, the exclusive use of dipyrone during preconception showed an OR=1.63 (95% CI 1.06-2.53) and dipyrone intake during lactation showed an OR=2.00 (95% CI 1.18-3.39). These results suggest that acetaminophen use during pregnancy may protect against development of early age leukemia in the offspring, whereas dipyrone use may act as a risk factor for such an outcome.


Assuntos
Analgésicos/efeitos adversos , Leucemia/induzido quimicamente , Leucemia/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Adolescente , Adulto , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Humanos , Lactente , Recém-Nascido , Leucemia/diagnóstico , Masculino , Exposição Materna , Gravidez , Efeitos Tardios da Exposição Pré-Natal/diagnóstico , Fatores de Risco , Adulto Jovem
19.
Environ Technol ; 36(17): 2198-209, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25732709

RESUMO

The environmental profile of milk production in Mexico was analysed for three manure management scenarios: fertilization (F), anaerobic digestion (AD) and enhanced anaerobic digestion (EAD). The study used the life cycle assessment (LCA) technique, considering a 'cradle-to-gate' approach. The assessment model was constructed using SimaPro LCA software, and the life cycle impact assessment was performed according to the ReCiPe method. Dairy farms with AD and EAD scenarios were found to exhibit, respectively, 12% and 27% less greenhouse gas emissions, 58% and 31% less terrestrial acidification, and 3% and 18% less freshwater eutrophication than the F scenario. A different trend was observed in the damage to resource availability indicator, as the F scenario presented 6% and 22% less damage than the EAD and AD scenarios, respectively. The magnitude of environmental damage from milk production in the three dairy manure management scenarios, using a general single score indicator, was 0.118, 0.107 and 0.081 Pt/L of milk for the F, AD and EAD scenarios, respectively. These results indicate that manure management systems with anaerobic digestion can improve the environmental profile of each litre of milk produced.


Assuntos
Esterco/análise , Gerenciamento de Resíduos/métodos , Anaerobiose , Ração Animal/análise , Animais , Biocombustíveis/análise , Indústria de Laticínios/métodos , Meio Ambiente , Eutrofização , Efeito Estufa , Gado , México
20.
J Colloid Interface Sci ; 265(2): 351-8, 2003 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-12962669

RESUMO

The electrochemical behavior of riboflavin (RF) adsorbed on different surfaces of inorganic matrices was investigated using modified carbon paste electrodes. Silica gel and sol-gel silica modified with niobium oxide were denominated as (SN) and (SN(sol-gel)), respectively. These materials were treated with a H3PO4 solution to graft phosphate groups and were denominated as (SNP) and (SNP(sol-gel)). The immobilization of RF on these materials indicated a high electrode stability, avoiding leaching out of the electroactive species (RF) from the electrode surface. The values of formal potential (E0') of the adsorbed RF on the different matrices changed from -283 (SNRF) up to -165 mV (SNPRF(sol-gel)) vs SCE in 0.1 moll(-1) NaNO3 solution at pH 7.0. Compared to the E0' for soluble RF, the values are shifted 183 up to 305 mV toward more positive potentials. The stability of the electrodes and the formal potential of the adsorbed RF on different matrices remained constant upon changing the solution pH from 3 to 8. Some kinetic parameters were estimated; indicating that all systems studied presented a good electron transfer rate.


Assuntos
Eletroquímica/métodos , Riboflavina/química , Carbono/química , Eletrodos , Elétrons , Concentração de Íons de Hidrogênio , Cinética , Nióbio/química , Transição de Fase , Fosfatos/química , Silício/química
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