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Hepatocytes constitute the majority of hepatic cells, and play a key role in controlling systemic innate immunity, via pattern-recognition receptors (PRRs) and by synthesizing complement and acute phase proteins. Leishmania infantum, a protozoan parasite that causes human and canine leishmaniasis, infects liver by establishing inside the Kupffer cells. The current study proposes the elucidation of the immune response generated by dog hepatocytes when exposed to L. infantum. Additionally, the impact of adding leishmanicidal compound, meglumine antimoniate (MgA), to parasite-exposed hepatocytes was also addressed. L. infantum presents a high tropism to hepatocytes, establishing strong membrane interactions. The possibility of L. infantum internalization by hepatocytes was raised, but not confirmed. Hepatocytes were able to recognize parasite presence, inducing PRRs [nucleotide oligomerization domain (NOD)1, NOD2 and Toll-like receptor (TLR)2] gene expression and generating a mix pro- and anti-inflammatory cytokine response. Reduction of cytochrome P 450s enzyme activity was also observed concomitant with the inflammatory response. Addition of MgA increased NOD2, TLR4 and interleukin 10 gene expression, indicating an immunomodulatory role for MgA. Hepatocytes seem to have a major role in coordinating liver's innate immune response against L. infantum infection, activating inflammatory mechanisms, but always balancing the inflammatory response in order to avoid cell damage.
The use of cactus cladodes in animal feed is well-established in semi-arid areas. The cactus Nopalea cochenillifera (L.) Salm-Dyck cladodes (Nopalea) have high acceptability amongst dairy cows and are resistant to carmine cochineal insects (Dactylopius opuntiae Cockerell), a problem in semi-arid regions, but in regions of prolonged drought, it has lower productivity compared with the cactus Opuntia stricta (Haw.) Haw cladodes (Opuntia), which is also resistant to the insect. The objective of the current study was to evaluate the intake and content of digestible material of dry matter (DM) and its components, feeding behaviour, microbial protein synthesis, nitrogen balance, blood parameters, performance and milk composition of Holstein cows fed a control diet, containing either Nopalea or Opuntia associated with different concentrate levels (225, 275, 325 and 375 g/kg). Ten cows with an initial average milk production of 20 ± 2.1 kg/day were distributed into a double 5 × 5 Latin square design. Diets containing 775 g roughage/kg and 225 g concentrate/kg promoted similar responses to the analysed variables regardless of the cactus cladode used, except for digestibility of neutral detergent fibre. Diets containing higher proportions of concentrate (325 and 375 g/kg) promoted greater DM intake and 3.5% fat-corrected milk yield. The diet containing Opuntia at 775:225 g/kg roughage:concentrate proportion is as effective as the control diet for Holstein cows producing 20 kg of milk/day. To promote greater milk production, higher proportions of concentrate should be added to diets using Opuntia.
The present study aimed to (i) assess the appetitive drives evoked by the visual cues of ultra-processed food and drink products and (ii) investigate whether text warnings reduce appetitive drives and consumers’ reported intentions to eat or drink ultra-processed products.
In Study I, a well-established psychometric tool was applied to estimate the appetitive drives associated with ultra-processed products using sixty-four image representations. Sixteen product types with four exemplars of a given product were included. Pictures from the International Affective Picture System (IAPS) served as controls. The two exemplars of each product type rated as more appetitive were selected for investigation in the second study. Study II assessed the impact of textual warnings on the appetitive drive towards these thirty-two exemplars. Each participant was exposed to two picture exemplars of the same product type preceded by a text warning or a control text. After viewing each displayed picture, the participants reported their emotional reactions and their intention to consume the product.
Controlled classroom experiments
Undergraduate students (Study I: n 215, 135 women; Study II: n 98, 52 women).
In Study I, the pictures of ultra-processed products prompted an appetitive motivation associated with the products’ nutritional content. In Study II, text warnings were effective in reducing the intention to consume and the appetitive drive evoked by ultra-processed products.
This research provides initial evidence favouring the use of text warnings as a public policy tool to curb the powerful influence of highly appetitive ultra-processed food cues.
The aim of this study was to determine the prevalence and risk factors for human papillomavirus (HPV) infection in the Southern region of the State of Bahia, evaluating the performance of alternative complementary methods for cervical lesion detection. Cervical samples from women who attended healthcare units were collected and diagnosed by visual inspection, cervical cytology and nested polymerase chain reaction (PCR). Moreover, hemi-nested PCR was performed to detect different HPV genotypes. The prevalence of HPV infection was 47·7%, with genotype 16 detected in most cases. Infection was associated with dyspareunia and bleeding (P < 0·001, odds ratio (OR) 5·6, 95% confidence interval (CI) 2·815–11·14) and hormonal contraceptive use (P = 0·007, OR 2·33, 95% CI 1·25–4·34). There was a positive correlation between positive PCR and positive visual inspection, cervical cytology and symptoms reported. Furthermore, visual inspection was twice as specific, and had a greater positive predictive value than cytology. We showed a high prevalence of HPV infection in Southern Bahia, with HPV 16 being the most common type, and visual inspection being most effective at detecting HPV lesions, corroborating the suggestion that it can be applied in routine gynecologic examinations for low-income populations.
In Northeast of Portugal sheep is reared under extensive systems. These systems frequently involve expressive body composition changes due to the storing and mobilization of body reserves, mainly fat. Body condition score (BCS) is the most common way to assess these reserves and the nutritional status of ewes. However due to the subjective nature of BCS, their quality has been questioned and other alternatives has been studied. For cattle there are some studies that use the real time ultrasonography (RTU) to evaluate the BCS (Schwager-Suter et al., 2000; Broring et al., 2003), but this approach was not tested in ewes. Therefore the aim of the present study was to establish a relationship between the BCS and ultrasound subcutaneous fat (SF) and Longissimus thoracis et lumborum muscle (LM) measurements.
Advances in infrared astronomy and in computing power have recently opened up an interesting area of the solar system for dynamical exploration. The survey of the sky made by The Infrared Astronomical Satellite (IRAS) in 1983 revealed the complex structure of the zodiacal dust cloud. We now know the inclination and nodes of the plane of symmetry of the cloud with respect to the ecliptic and we have evidence that the cloud is not rotationally symmetric with respect to the Sun. Of even more interest is the discovery by IRAS of prominent dust bands that circle the Sun in planes near-parallel to the ecliptic. In 1984, we suggested (Dermott et al., Nature, 312, 505-509) that the solar system dust bands discovered by IRAS are produced by the gradual comminution of the asteroids in the major Hirayama asteroid families. The confirmation of this hypothesis has involved: (1) The development of a new secular perturbation theory that includes the effects of Poynting-Robertson light drag on the evolution of the dust particle orbits; (2) The production of a new high resolution Zodiacal History File by IPAC (the Infrared Processing and Analysis Center at Caltech); (3) The development of the SIMUL code: a three-dimensional numerical model that allows the calculation of the thermal flux produced by any particular distribution of dust particle orbits. SIMUL includes the effects of planetary perturbations and PR drag on the dust particle orbits and reproduces the exact viewing geometry of the IRAS telescope. We report that these tools allow us to account in detail for the observed structure of the dust bands. They also allow us to show that there is evidence in the IRAS data for the transport of asteroidal dust from the main belt to the Earth by Poynting-Robertson light drag.
We studied the ontogenetic growth of goat wethers (castrated male goats) of the Saanen and Swiss Alpine breeds based on a large range of intraspecific body mass (BM). The body parts and the chemical constituents of the empty body were described by the allometric function by using BM and the empty body mass (EBM) as the predictors for morphological traits and chemical composition, respectively. We fitted the allometric scaling function by applying the SAS NLMIXED procedure, but to evaluate assumptions regarding variances in morphological and compositional traits, we combined the scaling function with homoscedastic (MOD1), and the heteroscedastic exponential (MOD2) and power-of-the-mean (MOD3) variance functions. We also predicted the ontogenetic growth by using the traditional log-log transformation and back-transformed results into the arithmetic scale (MOD4). We obtained predictions from MOD4 in the arithmetic scale by a two-step process, and evaluated MOD1, MOD2 and MOD3 by a model selection framework, and compared MOD4 with MOD1, MOD2 and MOD3 based on goodness-of-fit measures. Based on information criteria for model selection, heterogeneous variance functions were more likely to describe 10 over 36 traits with a low level of model selection uncertainty. One trait was predicted by averaging the MOD1 and MOD2 variance functions; and nine traits were better described by averaging the MOD2 and MOD3 variance functions. The predictions for other 16 traits were averaged from MOD1, MOD2 and MOD3. However, MOD4 better described 11 traits according to the goodness-of-fit measures. Depending on the variable being analyzed, the body parts and the chemical amounts exhibited the three types of allometric behavior with respect to BM and EBM, that is, positive, negative and isometric ontogenetic growth. Reference BMs, that is, 20, 27, 35 and 45 kg, were used to compute the net protein and energy requirements based on the first derivative of the scaling function, and the results were presented in reference to the EBM and EBM0.75. Both the net protein and energy requirements scaled to EBM0.75 increased from 20 to 45 kg of BM.
β-Adrenergic agonists (β-AA) are non-hormonal growth promoters which promote muscle hypertrophy in supplemented animals. The effects of two β-AA in combination with the immunocastration technique on the performance and carcass traits were evaluated using 96 feedlot Nellore males in a randomized complete block design with two sex conditions (immunocastrated (IC) v. non-castrated (NC)) and three treatments: CON (no β-agonists added), RH (300 mg of ractopamine hydrochloride/day, for 33 days) or ZH (80 mg of zilpaterol·hydrochloride animal/day for 30 days, removed 3 days for required withdrawal period). The trial was carried for 100 days where in the first 70 days animals did not receive β-AA (phase 1) and during the last 30 days they were treated with β-AA (phase 2). The performance and ultrasound measurements of longissimus muscle area (LMA), backfat thickness (BFT) and rump fat thickness (RFT) were evaluated in both phases. No sex condition v. treatment interactions were observed for any trait. The NC animals had higher average daily gain (ADG) and final BW than the IC animals, but they did not differ in dry matter intake (DMI) and feed efficiency (gain to feed). The NC animals showed greater LMA (P=0.0001) and hot carcass weight (P=0.0006), and smaller BFT (P=0.0007), RFT (P=0.0039) and percentage of kidney, pelvic and heart fat (P<0.0001) when compared with IC animals. The animals fed ZH showed greater ADG (P=0.0002), G : F (P<0.0001) and dressing per cent (P=0.0136) than those fed RH and CON diets. No differences in BW and DMI were observed. A interaction between treatment and time on feed was observed for LMA and BFT, in which the animals fed ZH diet showed greater LMA (P<0.01) and lower BFT (P<0.01) at 100 days than the animals fed RH and CON diets, whereas RH and CON diets did not differ. Immunocastration decreases muscle development and increases carcass finishing. In contrast, β-AA increases muscle and decreases fat deposition. The ZH has a higher action on the muscle metabolism than animals fed RH diet. However, RH diet achieves a better balance because it has an intermediary performance between non-supplemented and ZH animals and does not decrease the carcass fat.
The regional component (∆R) of the marine reservoir effect (MRE), which is crucial for the accurate calibration of radiocarbon ages of marine-influenced samples, was determined for the Cuban northwestern coast. Fifteen different locations were studied by 14C dating of pre-bomb known-age marine shells specimens of bivalves and gastropods from the Felipe Poey Museum collection. Accelerator mass spectrometry (AMS) 14C measurements were performed at the Radiocarbon Laboratory of the Universidade Federal Fluminense (LAC-UFF) and mean ΔR values were estimated. The distribution of results indicates ∆R values from −46±38 to 140±52 14C yr and a possible pattern related to the position along the coast and ocean dynamics. We present both mean values for each region and a general ∆R of 28±13 14C yr for the northwestern coast of Cuba.
The Radiocarbon Laboratory of the Universidade Federal Fluminense, in Brazil, has been successfully applying the zinc reduction method for graphitization of carbon samples since the development of its early protocols in 2009. Successive methodological research aiming to improve and, ultimately, optimize the precision and accuracy of our results indicates that graphitization temperatures as low as 460°C promote erratic 13C isotopic fractionation, but an approximately constant fractionation of about –5‰ is achieved at 520°C. In this work, we present isotope ratio mass spectrometry (IRMS) δ13C results for 14C reference materials graphitized at 550°C with variable amounts of zinc. Based on the results obtained from the addition of 20, 35, and 50 mg of zinc, we conclude that a slightly lower variation in 13C isotope fractionation during graphitization is obtained with less zinc. Moreover, the average isotopic fractionation is not altered by increasing the graphitization temperature from 520°C to 550°C.
We discuss some aspects of the chronology of the Tupiguarani occupation in the southeastern Brazilian coast based on the analyses of 3 charcoal samples from the Morro Grande archaeological site (Rio de Janeiro state). 14C beta spectroscopy and accelerator mass spectrometry (AMS) techniques were used to determine ages of 2920 ± 70 BP, 2600 ± 160 BP, and 510 ± 160 BP. The occurrence of these ancient dates in southeastern Brazil has important implications for understanding the origin and dispersion of Tupian populations from Amazonia, supporting recent hypotheses that their expansion must have begun well before 2000 BP. On the other hand, the most recent date is a strong indication of a possible reoccupation of the site by the same cultural group around the time. These results show that the Tupiguarani occupation began at least about 3000 yr ago and lasted until its collapse with the European invasion in the 16th century.
We discus here the prehistoric settlement of the central-south Brazilian coast, and, more specifically, 1 old radiocarbon date obtained for a costal shellmound, as well as its implications concerning the chronology attributed to the settlement process. The accelerator mass spectrometry (AMS) technique was used to determine the 14C age of charcoal from a shellmound on the southern coast of Rio de Janeiro. The resulting age was 7860 ± 80 BP, an unexpected result that reinforces 2 similar previously obtained dates for the same region. Brazilian archaeologists, however, have questioned those 2 dates, because they would predate by some 2000 yr the antiquity consensually accepted for the settlement of the central-south Brazilian littoral.
This study, which was carried out in the southern Brazilian Amazon region (Rondônia state and Humaitá, Southern Amazon state), presents and discusses the significance of carbon isotope data measured in soil profiles collected across natural boundaries of forest to savanna vegetation. The main objective of this study was to evaluate the expansion-regression dynamics of these vegetation units in relation to climate changes during the Holocene. 14C data from charcoal, soil organic matter (SOM) and its component humin fraction indicate that the organic matter in the studied soils is essentially Holocene in origin. 13C data indicate that C3 type plants were the dominant vegetation at all study areas in the early Holocene, and during the entire Holocene, in the forest sites of Central Rondônia state and in the forest site 50 km from the city of Humaitá. 13C data also indicate that C4 plants have influenced significantly the vegetation at the transitional forest and the Cerrado (wooded savanna) sites of Southern Rondônia state and the forest ecosystem located 20 km from the Humaitá city. These typical C4 type isotopic signatures probably reflect a drier climate during the mid-Holocene. The 13C records representing probably the last 3000 yr show an expansion of the forest, due to a climatic improvement, in areas previously occupied by savanna vegetation. These results and other published data for the Amazon region indicate that the areas representing today's forest-savanna boundaries have been determined by significant vegetation changes during the Holocene. The boundary between forest and savanna vegetation seems to be quite sensitive to climatic change and should be the focus of more extensive research to correlate climate and past vegetation dynamics in the Amazon region.
We present prehistoric mercury accumulation rates in a dated sediment core from Lagoa da Pata, a remote lake in São Gabriel da Cachoeira, northern Amazon. The sediment samples were subdivided for mercury and radiocarbon analyses. A group of 18 samples have been prepared at ANU for 14C dating by accelerator mass spectrometry (AMS). The dating results show a good correlation with depth in the core, down to 41,500 BP. Three distinct sections are clearly identified in the core. They consist of upper and lower organic-rich layers, separated by an inorganic layer which represents a short period of rapid accumulation around 18 ka BP. The mercury accumulation rate is found to be larger in the upper layer (18 ka to present) than in the lower one (41 ka to 25 ka), by a factor of three. The larger accumulation rate of mercury is probably associated with warmer temperatures and a higher frequency of forest fires during the Holocene.
After 22 yr of the low-level liquid scintillation counting 14C laboratory at the Center for Nuclear Energy in Agriculture (CENA) at São Paulo University (USP), Piracicaba, Brazil, and several collaborative projects with Brazilian and international researchers from distinct scientific areas, the first 14C accelerator mass spectrometry (AMS) laboratory in Latin America was installed at the Physics Institute of the Universidade Federal Fluminense (UFF), Niterói, Brazil. A 250kV single stage accelerator produced by National Electrostatics Corporation began its operation in 2012. In this work, we compare measurements performed at the AMS Radiocarbon Laboratory at UFF (LAC-UFF) with those performed at CENA and the University of Georgia (UGAMS), Georgia, USA. All the results obtained from distinct inorganic and organic samples were in very good agreement.
Hantavirus pulmonary syndrome (HPS) is the most frequently reported fatal rodent-borne disease in Brazil, with the majority of cases occurring in Santa Catarina. We analysed the clinical, laboratory and epidemiological data of the 251 confirmed cases of HPS in Santa Catarina in 1999–2011. The number of cases ranged from 10 to 47 per year, with the highest incidences in 2004–2006. Gastrointestinal tract manifestations were found in >60% of the cases, potentially confounding diagnosis and leading to inappropriate therapy. Dyspnoea, acute respiratory failure, renal failure, increased serum creatinine and urea levels, increased haematocrits and the presence of pulmonary interstitial infiltrate were significantly more common in HPS patients who died. In addition, we demonstrated that the six cases from the midwest region of the state were associated with Juquitiba virus genotype. The case-fatality rate in this region, 19·2%, was lower than that recorded for other mesoregions. In the multivariate analysis increase of serum creatinine and urea was associated with death by HPS. Our findings help elucidate the epidemiology of HPS in Brazil, where mast seeding of bamboo can trigger rodent population eruptions and subsequent human HPS outbreaks. We also emphasize the need for molecular confirmation of the hantavirus genotype of human cases for a better understanding of the mortality-related factors associated with HPS cases in Brazil.
Rickettsia rickettsii infection is being increasingly recognized as an important cause of fatal acute illness in Brazil, where this tick-borne disease is designated Brazilian spotted fever (BSF). In this study we report five fatal cases of BSF in employees of an animal shelter in an urban area in the municipality of Rio de Janeiro in southeast Brazil after a natural disaster on 11 January 2011. Four of the cases occurred from 27 January to 11 April 2011, while the fifth fatal case was identified in April 2012. Three cases were confirmed by molecular analysis and two by epidemiological linkage. An investigation of BSF was performed in the animal shelter, and blood samples were collected from 115 employees and 117 randomly selected dogs. The presence of high levels (1024–4096) of antibodies against spotted fever group rickettsiae was found in three (2·6%) employees and 114 (97·5%) dogs. These findings emphasize the need to consider BSF as a possible cause of undifferentiated febrile illness, especially dengue and leptospirosis, in patients occupationally exposed to dogs heavily infested by ticks, mainly working at kennels and animal shelters that have inadequate space for the animals housed and frequently providing an environment conducive to exposure to pathogens such as R. rickettsii.
The main objective of this study was to develop a polymeric drug delivery system for tamoxifen (TMX), intended to be injectable Eudragit® nanoparticles (NP) for breast cancer treatment. TMX-Eudragit-NP were characterized in terms of particle size, surface morphology, drug physical state by using photon correlation spectrometry (PCS), scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The entrapment efficiency (%EE) and in vitro drug release studies were estimated spectrophotometrically by UV-vis technique. The cell toxicity assay was performed in 4T1 cell line using MTT test. TMX-Eudragit-NP showed a maximum entrapment efficient of 23%. The size measurements were compared with the empty nanoparticles and showed values of TMX-Eudragit-NP = 133 ± 30 nm nm, and empty- NP = 273± 50 nm. The zeta potential of particles was +65 and +38 mV for TMX-Eudragit-NP and empty-NP respectively. FTIR studies did not indicate changes in chemical structure or polymer-drug interaction. The cytotoxicity against the 4T1 cells was affected significantly by the released amount of TMX, while empty-NP exhibit no significant cytotoxicity against mouse breast cancer cells (4T1 cell line).
Scanning Thermal Microscopy measurements with a resistive microprobe electrically heated were performed for different probe temperatures, for probe free in air and in contact with various specimens. The measured relative difference of Joule power dissipated in the probe when tip is in contact with a sample and when it is free in air is studied for different magnitude of the electrical current that heats the probe. A variation of this signal, never outlined before, is observed. A predictive modeling is used to explain these results and identify from the experimental data the global thermal conductance of the probe-sample thermal exchange for experiments performed in ambient conditions.
In this work, we present an analysis of SNe number ratios in spiral galaxies with different morphological subtypes, luminosities, sSFR, and metallicities, to provide important information about the physical properties of the progenitor populations.