Bone disease as a consequence of diabetes mellitus (DM) is not fully understood. The effects of high glucose (30 mM), high insulin (50 nM), or mannitol (30 mM; osmotic control) were evaluated on ...MC3T3-E1 cells (osteoblasts) in vitro. The mRNA and protein levels of parathyroid hormone (PTH) receptor (PTH1R), collagen I, RANKL, osteoprotegerin (OPG), alkaline phosphatase (ALP), and glucose transporter (GLUT1) were estimated by real-time polymerase chain reaction or Western blotting. The mineralization capacity was analyzed by von Kossa staining. High glucose induced overexpression of RANKL (2×) and OPG (30×), suggesting that RANKL-induced osteoclast activity might not be a dominant mechanism of bone disease in DM, since this increase was followed by increased OPG. Collagen I increased by 12×, indicating an excess of organic matrix production. The expression of ALP decreased by 50 %, indicating a deficit in mineralization capacity, confirmed by von Kossa staining. Mannitol induced similar effects as glucose suggesting that extracellular hyperosmolarity was able to stimulate organic matrix production. GLUT1 expression was not altered, and insulin did not reverse most of the effects of glucose, suggesting that glucose uptake by osteoblasts was not altered by high glucose. The data suggest that the bone fragility typical of DM is not a consequence of excessive bone reabsorption but is instead attributable to a defect in organic matrix mineralization. The heightened increase in OPG versus RANKL might cause a decrease in the bone-remodeling cycle. Osteoblasts appear to be more sensitive to extracellular hypertonicity than to the intracellular metabolic effects of hyperglycemia.
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Cellulose nanofibers (CNF) can present a high viscosity and thixotropic behavior when dispersed in water. In this work, CNF isolated from sugarcane bagasse and modified by ...N-oxyl-2,2,6,6-tetramethylpiperidine (TEMPO) oxidation was added to a solution of carboxymethyl cellulose (CMC). This process produced an unexpected viscosity due to a synergistic effect that was observed macroscopically through rheology analysis. The phenomenon known as depletion flocculation was observed, which was caused by the reduction of the excluded volume. The interactions of the system were studied by ultraviolet–visible spectroscopy (UV–Vis), optical microscopy, and cryogenic transmission electron microscopy (cryo-TEM), which demonstrated the presence of the particle/polymer repulsion and subsequent formation of domains composed of aligned micro and nanocellulose particles clusters and nanofibers distributed throughout the sample, forming a percolated 3D structure responsible for a strong gelling and colloidal stability.
Combinatorial antiretroviral therapy provided improvement of HIV patients' immune function and a decrease in the incidence of non-Hodgkin lymphoma (NHL). Diffuse large B-cell lymphoma (DLBCL) is one ...of the most common NHL forms affecting HIV+ patients. The present study aimed to evaluate the impact of HIV infection on the prognosis of patients treated for DLBCL in a reference cancer treatment center in Brazil.
A retrospective case-control study was developed with patients followed-up at the Brazilian National Cancer Institute, in which 243 DLBCL patients (91 HIV+ and 152 HIV-) were enrolled. HIV- controls were matched to HIV+ according to date of cancer diagnosis, clinical staging, primary cancer treatment and date of birth. Sociodemographic and cancer treatment data were extracted from medical charts. Kaplan-Meier analyses were carried out to estimate survival, while univariate and multiple Cox regression analyses were used to determine factors associated with mortality.
A total of 98 deaths were observed in a 5-year period after cancer diagnosis. A negative association of HIV infection with both overall and disease-specific survival 1 year after cancer diagnosis was observed hazard ratio (HR) = 1.98 and 1.96, respectively. The negative association with HIV infection with disease-specific survival remained significant for a 5-year period after cancer diagnosis (HR = 1.53). HIV viral load above 1000 copies/ml at study entry was also associated with shorter overall and cancer-specific survival.
HIV infection negatively impacted prognosis and mortality of DLBCL patients irrespective of cancer-related clinical factors.
Basidiomata of Phallales have a diversified morphology with adhesive gleba that exudes an odor, usually unpleasant that attracts mainly insects, which disperse the basidiospores. The genus Blumenavia ...belongs to the family Clathraceae and, based on morphological features, only two species are currently recognized: B. rhacodes and B. angolensis. However, the morphological characters adopted in species delimitations within this genus are inconsistent, and molecular data are scarce. The present study aimed to review and identify informative characters that contribute to the delimitation of Blumenavia species. Exsiccates from America and Africa were analyzed morphologically, and molecularly, using ITS, LSU, ATP6, RPB2 and TEF-1α markers for Maximum Parsimony, Bayesian and Maximum likelihood analyses, and also for coalescent based species delimitations (BP&P), as well as for bPTP, PhyloMap, Topo-phylogenetic and Geophylogenetic reconstructions. According to our studies, seven species can be considered in the genus: B. rhacodes and B. angolensis are maintained, B. usambarensis and B. toribiotalpaensis are reassessed, and three new species are proposed, B. baturitensis Melanda, M.P. Martín & Baseia, sp. nov., B. crucis-hellenicae G. Coelho, Sulzbacher, Grebenc & Cortez, sp. nov., and B. heroica Melanda, Baseia & M.P. Martín, sp. nov. Blumenavia rhacodes is typified by selecting a lectotype and an epitype. Macromorphological characters considered informative to segregate and delimit the species through integrative taxonomy include length of the basidiomata, color, width and presence of grooves on each arm as well as the glebifer position and shape. These must be clearly observed while the basidiomata are still fresh. Since most materials are usually analyzed after dehydration and deposit in collections, field techniques and protocols to describe fugacious characters from fresh specimen are demanded, as well as the use of molecular analysis, in order to better assess recognition and delimitation of species in Blumenavia.
•Bee Pollen mineral composition quantified by NIR spectroscopy and PLS regression.•Validated PLS models for quantification of Ca, Mg, Zn, P and K in bee pollen samples.•Quantification of minerals by ...diffuse reflectance spectra in the near infrared region.
Bee pollen consumption has increased in the last years, mainly due to its nutritional value and therapeutic applications. The quantification of mineral constituents is of great importance in order to evaluate both, the toxicity and the beneficial effect of essential elements. The purpose of this work was to quantify the essential elements, Ca, Mg, Zn, P and K, by diffuse reflectance spectra in the near infrared region (NIR) combined with partial least squares regression (PLS), which is a clean and fast method. Reference method used was ICP OES.
The determination coefficients for calibration models (R2) were above 0.87 and the mean percent calibration error varied from 5 to 10%. For external validation R2 values were higher than 0.76. The results indicated that NIR spectroscopy can be useful for an approximate quantification of these minerals in bee pollen samples and can be used as a faster alternative to the standard methodologies.
Abstract
Background and Aims
Developing novel therapies to battle the global public health burden of heart failure remains challenging. This study investigates the underlying mechanisms and potential ...treatment for 4-hydroxynonenal (4-HNE) deleterious effects in heart failure.
Methods
Biochemical, functional, and histochemical measurements were applied to identify 4-HNE adducts in rat and human failing hearts. In vitro studies were performed to validate 4-HNE targets.
Results
4-HNE, a reactive aldehyde by-product of mitochondrial dysfunction in heart failure, covalently inhibits Dicer, an RNase III endonuclease essential for microRNA (miRNA) biogenesis. 4-HNE inhibition of Dicer impairs miRNA processing. Mechanistically, 4-HNE binds to recombinant human Dicer through an intermolecular interaction that disrupts both activity and stability of Dicer in a concentration- and time-dependent manner. Dithiothreitol neutralization of 4-HNE or replacing 4-HNE-targeted residues in Dicer prevents 4-HNE inhibition of Dicer in vitro. Interestingly, end-stage human failing hearts from three different heart failure aetiologies display defective 4-HNE clearance, decreased Dicer activity, and miRNA biogenesis impairment. Notably, boosting 4-HNE clearance through pharmacological re-activation of mitochondrial aldehyde dehydrogenase 2 (ALDH2) using Alda-1 or its improved orally bioavailable derivative AD-9308 restores Dicer activity. ALDH2 is a major enzyme responsible for 4-HNE removal. Importantly, this response is accompanied by improved miRNA maturation and cardiac function/remodelling in a pre-clinical model of heart failure.
Conclusions
4-HNE inhibition of Dicer directly impairs miRNA biogenesis in heart failure. Strikingly, decreasing cardiac 4-HNE levels through pharmacological ALDH2 activation is sufficient to re-establish Dicer activity and miRNA biogenesis; thereby representing potential treatment for patients with heart failure.
Purpose
The decline in physical performance, assessed by physical tests such as the timed up and go (TUG) test, is a consequence of reduced physiological reserves at higher levels of a hierarchical ...process. This occurs due to changes in muscle architecture, including atrophy and fat infiltration into the muscles, which in turn lead to changes in muscle function, resulting in reduced muscle strength and power and, consequently, affecting physical performance. This study investigated predictive factors for physical performance in breast cancer survivor (BCS), focusing on intramuscular adipose tissue (IMAT), quadríceps muscle area (QMA), and muscular power.
Methods
This observational, analytical, and cross-sectional study included 23 women without a history of cancer (age, 58.5 ± 8.3 years; BMI, 27.2 ± 5.1 kg/m
2
) and 56 BCS (age, 58.5 ± 8.3 years; BMI, 27.2 ± 5.1 kg/m
2
). QMA and IMAT were assessed using computed tomography images. Muscular power and physical performance were measured using the 5-repetition sit-to-stand and TUG tests, respectively.
Results
IMAT (
r
= 0.4,
P
< 0.01) and muscular power (
r
= − 0.4,
P
< 0.01) were associated with TUG performance in BCS, whereas QMA (
r
= − 0.22,
P
= 0.10) showed no significant association. QMA (
r
= 0.55,
P
< 0.01) was associated with muscular power, while no significant association was found between IMAT and muscular power (
r
= − 0.05,
P
= 0.73). Age explained 19% (
P
< 0.01) of TUG performance variability. Adding muscular power increased explanatory power by 12% (
P
< 0.01), and including IMAT further increased it by 7% (
P
= 0.02) for TUG performance. Collectively, age, muscular power, and IMAT accounted for 38% of the performance variance in the TUG test (age,
B
= 0.06,
P
= 0.043; muscular power,
B
= − 0.01,
P
= 0.002; IMAT,
B
= − 0.05,
P
= 0.020).
Conclusions
Our findings suggest that IMAT and muscular power predict the physical performance of BCS, while QMA does not have the same predictive capability.
Iron niobates, pure and substituted with copper (Fe1−xCuxNbO4 with x = 0–0.15), were prepared by the solid-state method and characterized by X-ray diffraction, Raman spectroscopy, and magnetic ...measurements. The results of the structural characterizations revealed the high solubility of Cu ions in the structure and better structural stability compared to the pure sample. The analysis of the magnetic properties showed that the antiferromagnetic–ferromagnetic transition was caused by the insertion of Cu2+ ions into the FeNbO4 structure. The pure FeNbO4 structure presented an antiferromagnetic ordering state, with a Néel temperature of approximately 36.81K. The increase in substitution promoted a change in the magnetic ordering, with the state passing to a weak ferromagnetic order with a transition temperature (Tc) higher than the ambient temperature. The origin of the ferromagnetic ordering could be attributed to the increase in super-exchange interactions between Fe/Cu ions in the Cu2+-O-Fe3+ chains and the formation of bound magnetic polarons in the oxygen vacancies.
In this paper we analyze the descriptive statistics of the Google search volume for the terms related to the National Reserve of Copper and Associates (RENCA), a Brazilian mineral reserve in the ...Amazon of 4.6 million hectares, before and after the government signed the decree releasing it for exploration. First, we analyze the volume of searches for expressions related to RENCA in Google Trends using descriptive statistics; second, we assess the cross-correlation coefficient rho.sub.DCCA, which measures the cross-correlation between two nonstationary time series across different time scales. After the government announced the release of the RENCA reserve, there was an increase in the average volume of Google searches for related terms, showing people's concern about the announcement. By using the cross-correlation coefficient rho.sub.DCCA, we identify strong cross-correlations between the different expressions related to RENCA in Google Trends. Our work shows the utility of Google Trends as an indicator of the perception of environmental policies. Additionally, we show that rho.sub.DCCA can be used as a tool to measure the cross-correlation between synonyms extracted from Google Trends for various time scales.
The dynamics underlying severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection remain poorly understood. We identified a small cluster of patients in Brazil who experienced 2 ...episodes of coronavirus disease (COVID-19) in March and late May 2020. In the first episode, patients manifested an enhanced innate response compared with healthy persons, but neutralizing humoral immunity was not fully achieved. The second episode was associated with different SARS-CoV-2 strains, higher viral loads, and clinical symptoms. Our finding that persons with mild COVID-19 may have controlled SARS-CoV-2 replication without developing detectable humoral immunity suggests that reinfection is more frequent than supposed, but this hypothesis is not well documented.
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