Polymersomes for Sustained Delivery of a Chalcone Derivative Targeting Glioblastoma Cells

Glioblastoma (GBM) is a primary malignant tumor of the central nervous system responsible for the most deaths among patients with primary brain tumors. Current therapies for GBM are not effective, with the average survival of GBM patients after diagnosis being limited to a few months. Chemotherapy is difficult in this case due to the heterogeneity of GBM and the high efficacy of the blood-brain barrier, which makes drug absorption into the brain extremely difficult. In a previous study, 3',4',3,4,5-trimethoxychalcone (MB) showed antiproliferative and anti-invasion activities toward GBM cells. Polymersomes (PMs) are an attractive, new type of nanoparticle for drug administration, due to their high stability, enhanced circulation time, biodegradability, and sustained drug release. In the present study, different MB formulations, PEG2000-PCL and PEG5000-PCL, were synthesized, characterized, and compared in terms of 14-day stability and in vitro cytotoxicity (hCMEC/D3 and U-373 MG).

Effect of glycoelectrolytic supplement on post-weaning piglet performance and intestinal integrity

This study evaluated the effects of glycoelectrolytic supplements on the performance, blood parameters, and intestinal morphology of piglets during the post-weaning period. In the study, a total of 240 piglets weaned aged 17 22.60 + 1.10 days were used. The control group (n = 120) received only water, and the treatment group (n = 120) received an oral glycoelectrolytic supplement diluted in water (0.75%) during the first three days after weaning. Feed intake, daily weight gain, final weight, feed conversion ratio, and post-weaning mortality were evaluated. On the third day after weaning, the blood glucose levels of all piglets were analyzed. Blood was collected from 12 piglets from each treatment group on day 3 after weaning for blood count analysis, and intestinal fragments were collected for anatomopathological and morphometric evaluation. Better feed conversion ratio (1.29) and higher consumption of liquids (0.639 L/day) were observed in the piglet group supplemented with glycoelectrolytes on day 3 after weaning (P < 0.05). The supplemented group presented a higher glycemic index (80.78 mg/dL), average corpuscular volume (67.35 fL), and average corpuscular hemoglobin (20.46 pg) than the control group (P < 0.05). The evaluation of intestinal integrity and the probability of diarrhea occurrence were similar between the groups (P > 0.05). Oral glycoelectrolytic supplementation can be an option for piglets immediately after weaning as it improves feed conversion and consumption of liquids, in addition to increasing blood glucose without the occurrence of diarrhea, thus reducing dehydration and energy deficit.

Anillin and the microtubule bundler PRC1 maintain myosin in the contractile ring to ensure completion of cytokinesis

Cytokinesis is the last step of cell division, when one cell physically divides into two cells. Cytokinesis is driven by an equatorial contractile ring and signals from antiparallel microtubule bundles (the central spindle) that form between the two masses of segregating chromosomes. Bundling of central spindle microtubules is essential for cytokinesis in cultured cells. Using a temperature-sensitive mutant of SPD-1, the homolog of the microtubule bundler PRC1, we demonstrate that SPD-1 is required for robust cytokinesis in the Caenorhabditis elegans early embryo. SPD-1 inhibition results in broadening of the contractile ring, creating an elongated intercellular bridge between sister cells at the last stages of ring constriction that fails to seal. Moreover, depleting anillin/ANI-1 in SPD-1-inhibited cells results in myosin loss from the contractile ring during the second half of furrow ingression, which in turn results in furrow regression and cytokinesis failure. Our results thus reveal a mechanism involving the joint action of anillin and PRC1, which operates during the later stages of furrow ingression to ensure continued functioning of the contractile ring until cytokinesis is complete.

On the structural, electronic, and optical properties of L-histidine crystal: a DFT study

CONTEXT

The monoclinic L-histidine crystal is critical for protein structure and function and is also found in the myelin of brain nerve cells. This study numerically examines its structural, electronic, and optical properties. Our findings indicate that the L-histidine crystal has an insulating band gap of approximately 4.38 eV. Additionally, electron and hole effective masses range between 3.92[Formula: see text]-15.33[Formula: see text] and 4.16[Formula: see text]-7.53[Formula: see text], respectively. Furthermore, our investigation suggests that the L-histidine crystal is an excellent UV collector due to its strong optical absorption activity for photon energies exceeding 3.5 eV.

METHODS

To investigate the structural, electronic, and optical properties of L-histidine crystals, we used the Biovia Materials Studio software to conduct Density Functional Theory (DFT) simulations as implemented in the CASTEP code. Our DFT calculations were performed using the generalized gradient approximation (GGA) as parameterized by the Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional, with an additional dispersion energy correction (PBE [Formula: see text] TS) based on the model proposed by Tkatchenko and Scheffler to describe van der Waals interactions. Additionally, we employed the norm-conserving pseudopotential to treat core electrons.

Establishment of methods to analyze the structural and functional integrity of the quail (Coturnix coturnix japonica) sperm plasma membrane

1. The objectives of this study were to establish the use of the fluorophores Hoechst 33342 and propidium iodide for the evaluation of sperm plasma membrane integrity and to identify an adequate hypoosmotic solution for the evaluation of sperm membrane functionality in quails.2. Sperm samples were collected from the vas deferens of nine quails. After initial evaluation, the samples were subjected to a flash-frozen assay. Three treatments with the following proportions of fresh sperm and sperm subjected to flash freezing were prepared as follows: 100:0 (T100), 50:50 (T50), and 0:100 (T0). The hypoosmotic swelling test used distilled water (0 mOsm/l) and fructose solutions (50, 100, and 200 mOsm/l).3. Immediately after recovery, the samples showed 75.6 ± 5.0% motility with vigour of 3.7 ± 0.3 and 96.1 ± 0.5% of the sperm appeared normal. The membrane integrity test showed 62.2 ± 5.2% intact sperm at T100, 29.0 ± 4.1% at T50 and 0.1 ± 0.1% at T0. Moreover, a greater number of reactive sperm (74.7 ± 6.7%) were observed when incubated in distilled water (0 mOsm/l) in comparison to other solutions (P < 0.05).4. The association of fluorescent probes composed of Hoechst 33342 and propidium iodide provided an efficient assessment of the integrity of the plasmatic membrane of quail spermatozoa. However, the study identified that the hypoosmotic swelling test has little predictive value regarding sperm membrane functionality in this species.

Lung branching morphogenesis is accompanied by temporal metabolic changes towards a glycolytic preference

Background

Lung branching morphogenesis is characterized by epithelial-mesenchymal interactions that ultimately define the airway conducting system. Throughout this process, energy and structural macromolecules are necessary to sustain the high proliferative rates. The extensive knowledge of the molecular mechanisms underlying pulmonary development contrasts with the lack of data regarding the embryonic lung metabolic requirements. Here, we studied the metabolic profile associated with the early stages of chicken pulmonary branching.

Methods

In this study, we used an ex vivo lung explant culture system and analyzed the consumption/production of extracellular metabolic intermediates associated with glucose catabolism (alanine, lactate, and acetate) by ¹H-NMR spectroscopy in the culture medium. Then, we characterized the transcript levels of metabolite membrane transporters (glut1, glut3, glut8, mct1, mct3, mct4, and mct8) and glycolytic enzymes (hk1, hk2, pfk1, ldha, ldhb, pdha, and pdhb) by qPCR. ldha and ldhb mRNA spatial localization was determined by in situ hybridization. Proliferation was analyzed by directly assessing DNA synthesis using an EdU-based assay. Additionally, we performed western blot to analyze LDHA and LDHT protein levels. Finally, we used a Clark-Type Electrode to assess the lung explant's respiratory capacity.

Results

Glucose consumption decreases, whereas alanine, lactate, and acetate production progressively increase as branching morphogenesis proceeds. mRNA analysis revealed variations in the expression levels of key enzymes and transporters from the glycolytic pathway. ldha and ldhb displayed a compartment-specific expression pattern that resembles proximal–distal markers. In addition, high proliferation levels were detected at active branching sites. LDH protein expression levels suggest that LDHB may account for the progressive rise in lactate. Concurrently, there is a stable oxygen consumption rate throughout branching morphogenesis.

Conclusions

This report describes the temporal metabolic changes that accompany the early stages of chicken lung branching morphogenesis. Overall, the embryonic chicken lung seems to shift to a glycolytic lactate-based metabolism as pulmonary branching occurs. Moreover, this metabolic rewiring might play a crucial role during lung development.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13578-021-00654-w.

Computational structural, electronic and optical properties of the palmitic acid in its C form

In this work, we report a theoretical study of the structural, electronic, and optical properties of palmitic acid crystal in its C form under DFT calculations level. Palmitic acid is a fatty acid that constitutes the large majority of vegetable oils with recognized potential applications in medicine, pharmaceuticals, cosmetics technology, foods, and fuel. As a main result, we have found that the electronic bandstructure reveals an indirect gap given by 3.713 eV (E→B andE→Γ), as a main bandgap, while the secondary bandgaps found were 4.175 eV (γ₁→Γ) and 4.172 eV (γ₂→B). It behaves like a wide bandgap semiconductor, which points to potential applications in optoelectronic devices.

IL-1β-pre-conditioned mesenchymal stem/stromal cells' secretome modulates the inflammatory response and aggrecan deposition in intervertebral disc

Mesenchymal stem/stromal cells (MSCs) have been increasingly used in clinical trials for low-back pain (LBP) and intervertebral disc (IVD) degeneration with promising results. Their action mechanisms are not fully understood, but they reduce IVD pro-inflammatory markers in a pro-inflammatory/degenerative IVD microenvironment. In this study the therapeutic potential of the MSC secretome, as an alternative cell-free approach for treating degenerated IVDs, was examined. Human bone marrow-derived MSC secretome (MSCsec) was collected after 48 h of preconditioning in IL-1β (10 ng/mL) and low oxygen (6 % O2), mimicking the degenerative IVD. IL-1β-pre-conditioning of MSCs increased secretion of pro-inflammatory markers hIL-6, hIL-8, hMCP-1, etc. The therapeutic effect of MSCsec was tested in a pro-inflammatory/degenerative IVD ex vivo model. MSCsec down-regulated IVD gene expression of pro-inflammatory cytokines (bIL-6, bIL-8) and matrix degrading enzyme bMMP1, while bMMP3 and bTIMP2 were up-regulated, at 48 h. After 14 d, MSCsec-treated IVDs revealed increased aggrecan deposition, although no differences in other ECM components were observed. Protein analysis of the MSCsec-treated IVD supernatant revealed a significant increase of CXCL1, MCP-1, MIP-3α, IL-6, IL-8 and GRO α/β/γ (related to TNF, NOD-like receptor and neutrophil chemotaxis signalling), and a decrease of IFN-γ, IL-10, IL-4, IL-5 and TNF-α (associated with T-cell receptor signalling). MSCsec-treated IVD supernatants did not promote angiogenesis and neurogenesis in vitro. Overall, MSCsec can be a safe therapeutic approach, presenting a strong immunomodulatory role in degenerated IVD while potentiating aggrecan deposition, which can open new perspectives on the use of MSCsec as a cell-based/ cell-free therapeutic approach to LBP.

Multiple Sclerosis Patient Management During the COVID-19 Pandemic: Practical Recommendations From the Portuguese Multiple Sclerosis Study Group (GEEM)

The spread of the COVID-19 pandemic has imposed significant challenges on healthcare provision, requiring changes in the conventional patient management, particularly in chronic diseases like multiple sclerosis (MS). To increase patient safety and reduce the risk of infection, while ensuring an appropriate and regular follow-up, tele-medicine gained prominence as a valid alternative to face-to-face appointments. However, the urgency of the implementation and the lack of experience in most MS centers led to “ad hoc” and extremely diverse approaches, which now merit to be standardized and refined. Indeed, while tele-consultation cannot fully replace face-to-face visits, it certainly can, and will, be incorporated as part of the routine care of MS patients in the near future. Bearing this in mind, the Portuguese Multiple Sclerosis Study Group (GEEM) has developed a set of recommendations for the usage of tele-medicine in the management of MS patients, both during the pandemic and in the future. The consensus was obtained through a two-step modified Delphi methodology, resulting in 15 recommendations, which are detailed in the manuscript.

Equatorial Non-muscle Myosin II and Plastin Cooperate to Align and Compact F-actin Bundles in the Cytokinetic Ring

Cytokinesis is the last step of cell division that physically partitions the mother cell into two daughter cells. Cytokinesis requires the assembly and constriction of a contractile ring, a circumferential array of filamentous actin (F-actin), non-muscle myosin II motors (myosin), and actin-binding proteins that forms at the cell equator. Cytokinesis is accompanied by long-range cortical flows from regions of relaxation toward regions of compression. In the C. elegans one-cell embryo, it has been suggested that anterior-directed cortical flows are the main driver of contractile ring assembly. Here, we use embryos co-expressing motor-dead and wild-type myosin to show that cortical flows can be severely reduced without major effects on contractile ring assembly and timely completion of cytokinesis. Fluorescence recovery after photobleaching in the ingressing furrow reveals that myosin recruitment kinetics are also unaffected by the absence of cortical flows. We find that myosin cooperates with the F-actin crosslinker plastin to align and compact F-actin bundles at the cell equator, and that this cross-talk is essential for cytokinesis. Our results thus argue against the idea that cortical flows are a major determinant of contractile ring assembly. Instead, we propose that contractile ring assembly requires localized concerted action of motor-competent myosin and plastin at the cell equator.

Exploring the association of predisposing factors of Cerebral Palsy and developmental defects of enamel: a case-control study

AIM

To evaluate the occurrence of developmental defects of enamel (DDE) in children and adolescents with Cerebral Palsy (CP) and to analyze the effect of common factors in the etiology of CP on the occurrence of DDE.

METHODS

A case-control study was carried out using the modified DDE index to classify enamel defects. The study group (SG) consisted of 45 participants with CP aged between three and 14 years. The control group (CG) consisted of 88 normotypical schoolchildren, paired by gender and age group. Caregivers answered a questionnaire on their socioeconomic status and medical history. The Chi-square tests, bivariate and multivariate analysis were performed (level significance < 0.05).

RESULTS

The occurrence of DDE in SG and CG was 60% and 64.8%, respectively (p value = 0.726). The most frequent defect observed in SG was diffuse opacity (44.4%), followed by demarcated opacity (26.7%) and enamel hypoplasia (2.2%). No difference was observed in the defect's distribution among both groups (p value = 0.083). For SG, the bivariate analysis revealed a statically significant association between the presence of DDE and age group 7-14 years old and maternal schooling below 11 years. After adjusting for confounding variables, age, family income and maternal schooling were not associated with DDE.

CONCLUSION

In conclusion, the occurrence of DDE was high and similar in both groups. The pre, peri or post-natal factors associated with CP were not significant for the presence of DDE.

Evaluation of MMP-10 and TIMP-1 levels associated with Resveratrol supplementation

Introduction Resveratrol (RSV) is a natural phytoalexin present in abundance in grapes, berries, peanuts and red wine. The main benefits of resveratrol ingestion are due to its anti-inflammatory and antioxidant properties. This compound also induces therapeutic benefits in the remodelling of extracellular matrix (ECM), which plays an important role in the regulation of the activity of matrix metalloproteinases (MMPs) and its tissue inhibitors of metalloproteinases (TIMPs). The MMPs are a family of zinc dependent endopeptidases, with an important role in the physiological and pathological remodelling of ECM, once the activity of MMPs can be regulated by TIMPs. This regulation is essential, since if there is an imbalance between the MMPs and TIMPs there’s destruction of the ECM, leading to the development of several pathologies.

Objectives Evaluate RSV potential by determining serum and salivary levels of MMP-10 and TIMP-1.

Methodology The study population included 27 undergraduates between the ages of 18 and 30, divided into a control group (placebo) and an intervention group, supplemented with 100 mg RSV/day, during 30 days. MMP-10 and TIMP-1 levels were determined by slot blot. The results were analysed using a GraphPad Prism version 5 software for Windows (GraphPad Software, San Diego, California, USA).

Results It was verified the existence of a linear correlation between the serum and salivary levels of TIMP-1, as well as a tendency of increase of this biomarker after RSV supplementation. In all indicators studied, supplementation with this compound wasn’t harmful.

Conclusion The rising trend verified at TIMP-1 in both fluids may reflect benefits in the individuals under study, demonstrating that saliva has potential as a study biofluid for this type of biochemical markers. It was also verified that supplementation with this compound did not damage the evaluated parameters and, therefore, the RSV potential shouldn’t be rejected.

Formulating octyl methoxycinnamate in hybrid lipid-silica nanoparticles: An innovative approach for UV skin protection

Sunscreens have been employed on daily skin care for centuries. Their role in protecting the skin from sun damage, avoiding accelerated photoaging and even limiting the risk of development of skin cancer is unquestionable. Although several chemical and physical filters are approved as sunscreens for human use, their safety profile is dependent on their concentration in the formulation which governs their acceptance by the regulatory agencies. A strategic delivery of such molecules should provide a UV protection and limit the skin penetration. Solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) may offer an alternative approach to achieve a synergistic effect on the UV protection when loaded with sunscreens as particles themselves also have a UV light scattering effect. Besides, the lipid character of SLN and NLC improves the encapsulation of lipophilic compounds, with enhanced loading capacity. Silica nanoparticles have also been employed in sunscreen formulations. Due to the formed sol-gel complexes, which covalently entrap sunscreen molecules, a controlled release is also achieved. In the present work, we have developed a new sunscreen formulation composed of hybrid SLN-Silica particles loaded with octyl methoxycinnamate (Parsol®MCX), and their further incorporation into a hydrogel for skin administration. Hybrid SLN-silica particles of 210.0 ± 3.341 nm of mean size, polydispersity below 0.3, zeta potential of ca. |7| mV, loading capacity of 19.9% and encapsulation efficiency of 98.3% have been produced. Despite the slight negative surface charge, the developed hybrid nanoparticles remained physicochemically stable over the study period. Turbiscan transmission profiles confirmed the colloidal stability of the formulations under stress conditions. The texture profile analysis of Parsol-SLN and Parsol-SLN-Si revealed semi-solid properties (e.g. adhesiveness, hardness, cohesiveness, springiness, gumminess, chewiness, resilience) suitable for topical application, together with the bioadhesiveness in the skin of pig ears. The non-irritation profile of the hybrid nanoparticles before and after dispersion into Carbopol hydrogels was confirmed by HET-CAM test.

Composition of semen and foreskin mucosa aerobic microbiota and its impact on sperm parameters of captive collared peccaries (Pecari tajacu)

AIM

To evaluate the bacterial composition of collared peccary semen and foreskin mucosa, and to verify the sensitivity of isolates to antimicrobials used in semen conservation and to Aloe vera gel, which is an alternative external cryoprotectant.

METHODS AND RESULTS

Nine foreskin mucosa and ejaculate samples from adult animals were used. Sperm characteristics and bacterial load were evaluated in fresh semen. The preputial mucosa and semen bacterial isolates were identified and tested against five concentrations of each antimicrobial (streptomycin-penicillin and gentamicin) and A. vera gel. Corynebacterium sp. and Staphylococcus sp. were isolated in greater numbers than others in both semen (64·10 and 20·51%, respectively) and the foreskin mucosa (60·60 and 24·25%, respectively), and ranged from 0·4 to 21 × 10⁵ colony-forming units (CFU) per ml. The average load of Corynebacterium sp. was negatively correlated (P < 0·05) with the sperm membrane integrity (r = -0·73055) and curvilinear velocity (r = -0·69048). Streptomycin-penicillin and gentamicin inhibited most micro-organisms, and A. vera showed lower antimicrobial activity.

CONCLUSION

Several Gram-positive bacteria are present in semen and foreskin mucosa of collared peccary, and the benefits of using primarily penicillin-streptomycin and gentamicin antimicrobials in the bacterial control of diluted semen of these animals are strongly indicated.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provides insight into the reproductive microbiota of captive male-collared peccary. This work provides a theoretical basis to assist reproductive biotechnologies for ex situ conservation of the species.

Spinal Myoclonus: Is It An Anesthetic Mystery?

The goal is to present a descriptive study related an unprecedent case of spinal myoclonus (SM) following subarachnoid anesthesia (SA). SM are sudden, brief, involuntary non-generalized spasms that can be an adverse effect of drug administration via neuraxial routes. Female, 67y, ASA II, proposed for hip replacement surgery, with normal preoperative exams. 7min after SA with 10mg of bupivacaine 0,5%, no motor blockade observed, and patient complained of unbearable pain in legs and perineum and bilateral, asymmetrical and arrhythmic myoclonic movements in the lower limbs. The latter solved after 48h of general anesthesia and rocuronium perfusion, amongst other therapeutics. Accordingly, intrathecal bupivacaine appears to be the SM most likely cause, regarding the absence of neurologic and electrolyte disorders, spinal cord direct trauma, drug exchange and normal perioperative examination, imaging and laboratory testing.It is mandatory to always take the patients' anaesthetic histories and recognize, treat and report rare anaesthetic complications.

Crosslinking activity of non-muscle myosin II is not sufficient for embryonic cytokinesis in C. elegans

Cytokinesis in animal cells requires the assembly and constriction of a contractile actomyosin ring. Non-muscle myosin II is essential for cytokinesis, but the role of its motor activity remains unclear. Here, we examine cytokinesis in C. elegans embryos expressing non-muscle myosin motor mutants generated by genome editing. Two non-muscle motor-dead myosins capable of binding F-actin do not support cytokinesis in the one-cell embryo, and two partially motor-impaired myosins delay cytokinesis and render rings more sensitive to reduced myosin levels. Further analysis of myosin mutants suggests that it is myosin motor activity, and not the ability of myosin to crosslink F-actin, that drives the alignment and compaction of F-actin bundles during contractile ring assembly, and that myosin motor activity sets the pace of contractile ring constriction. We conclude that myosin motor activity is required at all stages of cytokinesis. Finally, characterization of the corresponding motor mutations in C. elegans major muscle myosin shows that motor activity is required for muscle contraction but is dispensable for F-actin organization in adult muscles.

This article has an associated ‘The people behind the papers’ interview.

Highlighted Article: The motor activity of non-muscle myosin II is essential for cytokinesis and contributes to all stages of the process in C. elegans embryos.

Oral health-related quality of life in caregivers of individuals with Cerebral Palsy: a case-control study

AIM

The object of this study is to evaluate the oral health-related quality of life (OHRQoL) of caregivers of individuals with Cerebral Palsy (CP).

METHODS

Ninety-eight caregivers of individuals with CP (SG) and 196 caregivers of individuals without special needs (CG) completed the reduced version of the Oral Health Impact Profile (OHIP-14). In addition, a questionnaire with demographic and socioeconomic questions was used. Groups were matched according to gender, schooling and family income. Fisher's exact tests, Chi square and Mann-Whitney, and bi/multivariate logistic regression were used (p < 0.05).

RESULTS

The impact on OHRQoL was similar for SG and CG (OHIP-14 total score). For SG, the high negative impact was in the following OHIP domains: "Functional limitation", "Physical disability", "Psychological incapacity" and "Disadvantages". For SG, a higher number of caregivers was single, unemployed, received government financial aid. There was a statistically significant association between the number of children a caregiver has and a negative impact on OHRQoL.

CONCLUSIONS

Being a caregiver of children with or without CP had a negative impact of similar magnitude on ORHQoL. The negative impact on OHRQoL of caregivers of children with CP was associated with having a high number of children; the higher the number of children, the greater the negative impact on their OHRQoL.

Short communication: In vitro and in vivo probiotic potential of Lactobacillus plantarum B7 and Lactobacillus rhamnosus D1 isolated from Minas artisanal cheese

Some Lactobacillus strains may contribute to the health of the host when administered in adequate concentrations, demonstrating their probiotic potential. In contrast, Listeria monocytogenes is a foodborne pathogen that can cause enteropathy, meningoencephalitis, abortion, and septicemia. The aim of this survey was to evaluate the in vitro and in vivo probiotic potential of Lactobacillus plantarum B7 and Lactobacillus rhamnosus D1, isolated from Minas artisanal cheese of the Serra da Canastra (Minas Gerais, Brazil), against Lis. monocytogenes. We submitted B7 and D1 to in vitro testing (antibiogram, tolerance to bile salts and artificial gastric fluid, and spot-on-lawn) and in vivo testing (relative weight gain in mice). Both Lactobacillus strains demonstrated in vitro inhibitory activity against Lis. monocytogenes, as well as sensitivity to antimicrobials and resistance to gastric acids and bile salts. In the in vivo assays, mice treated with D1 gained more weight than mice in the other groups. These results indicate that D1 could have higher probiotic potential than B7 because improvements in feed conversion may help animals fight infection.

Effects of pre- or post-exercise whey protein supplementation on body fat and metabolic and inflammatory profile in pre-conditioned older women: A randomized, double-blind, placebo-controlled trial

BACKGROUND AND AIM

Protein supplementation and resistance training (RT) are interventions that may counteract decline in muscle mass and increase in fat mass, thus reducing the risk of developing chronic diseases during the aging process. The objective of this study was to investigate the effect of whey protein (WP) pre- or post-RT on metabolic and inflammatory profile in pre-conditioned older women.

METHODS AND RESULTS

Seventy older women participated in this investigation and were randomly assigned to one of three groups: WP pre-RT and placebo post-RT (WP-PLA, n = 24), placebo pre-RT and WP post-RT (PLA-WP, n = 23) and placebo pre and post-RT (PLA-PLA, n = 23). Each group ingested 35 g of PLA or WP pre- and post-RT. RT was carried out over 12 weeks (three times/week; 3 x 8-12 repetition maximum). Body composition, blood pressure, blood samples and dietary intake were assessed pre- and post-intervention. After the intervention, WP groups showed greater improvements in appendicular lean soft tissue (ALST: WP-PLA, 3.1%; PLA-WP, 3.9%; PLA-PLA, 1.8%) and total cholesterol/high density lipoprotein cholesterol ratio (TC/HDL-C: WP-PLA, -12.11%; PLA-WP, -13.2%; PLA-PLA, -0.7) when compared with PLA-PLA. WP post-RT also showed improvements (P < 0.05) in ALST/appendicular fat mass ratio (PLA-WP, 5.8%; PLA-PLA, 1.3%), total body fat (PLA-WP, -3.8%; PLA-PLA: -0.1) and trunk fat mass (PLA-WP, -3.1%; PLA-PLA, -0.3%) when compared with PLA-PLA.

CONCLUSION

WP pre- or post- RT promotes improvements in ALST and TC/HDL-C ratio in pre-conditioned older women. WP administered after RT was more effective in improving metabolic health Z-score and in reducing body fat compared to placebo group.

Environmental effects on collared peccaries (Pecari tajacu) serum testosterone, testicular morphology, and semen quality in the Caatinga biome

The objective of the study was to understand the influence of climatic variations in a semiarid environment on serum testosterone, testicular morphology and semen quality in collared peccaries (Pecari tajacu). Reproductive metrics (semen quality, testicular morphometry and testosterone serum profiles) of 10 mature males were measured monthly for 18 months. Meteorological data (rainfall, air temperature, relative humidity, wind speed and radiant heat load) also were recorded during the same period. Rainfall regimes were classified in different classes (Class 1: months with no rain; Class 2: months with up to 50 mm of rain; and Class 3: months with >50 mm of rain). Among rainfall classes, average air temperature (°C) and relative humidity (%) were different. Climatic changes between rainfall classes did not lead to overall variations of testicular size, testosterone production, and semen metrics. However, relative humidity recorded before semen collection (one day, one week, or over 51-55 days) was positively correlated (P < 0.05) with semen motility metrics (total motility, beat cross frequency and straightness) and sperm subpopulations (medium and static sperm), as well as with volume. Negative correlations (P < 0.05) were revealed between air temperature and the same semen motility patterns and volume. Additionally, radiant head load measured on the day of semen collection negatively influenced (P < 0.05) sperm straightness. This study demonstrates for the first time that no seasonal changes could be detected overt the 18-month period on the serum testosterone, testicular morphology and semen quality of collared peccaries raised in the Caatinga biome; however, it is expected that long term environmental changes will influence the reproductive physiology of species leaving in that habitat.

The ARP2/3 complex prevents excessive formin activity during cytokinesis

Cytokinesis completes cell division by constriction of an actomyosin contractile ring that separates the two daughter cells. Here we use the early Caenorhabditis elegans embryo to explore how the actin filament network in the ring and the surrounding cortex is regulated by the single cytokinesis formin CYK-1 and the ARP2/3 complex, which nucleate nonbranched and branched filaments, respectively. We show that CYK-1 and the ARP2/3 complex are the predominant F-actin nucleators responsible for generating distinct cortical F-actin architectures and that depletion of either nucleator affects the kinetics of cytokinesis. CYK-1 is critical for normal F-actin levels in the contractile ring, and acute inhibition of CYK-1 after furrow ingression slows ring constriction rate, suggesting that CYK-1 activity is required throughout ring constriction. Surprisingly, although the ARP2/3 complex does not localize in the contractile ring, depletion of the ARP2 subunit or treatment with ARP2/3 complex inhibitor delays contractile ring formation and constriction. We present evidence that the delays are due to an excess in formin-nucleated cortical F-actin, suggesting that the ARP2/3 complex negatively regulates CYK-1 activity. We conclude that the kinetics of cytokinesis are modulated by interplay between the two major actin filament nucleators.

Nuclear organization and morphology of cholinergic neurons in the brain of the rock cavy (Kerodon rupestris) (Wied, 1820)

The aim of this study was to conduct cytoarchitectonic studies and choline acetyltransferase (ChAT) immunohistochemical analysis to delimit the cholinergic groups in the encephalon of the rock cavy (Kerodon rupestris), a crepuscular Caviidae rodent native to the Brazilian Northeast. Three young adult animals were anesthetized and transcardially perfused. The encephala were cut in the coronal plane using a cryostat. We obtained 6 series of 30-μm-thick sections. The sections from one series were subjected to Nissl staining. Those from another series were subjected to immunohistochemistry for the enzyme ChAT, which is used in acetylcholine synthesis, to visualize the different cholinergic neural centers of the rock cavy. The slides were analyzed using a light microscope and the results were documented by description and digital photomicrographs. ChAT-immunoreactive neurons were identified in the telencephalon (nucleus accumbens, caudate-putamen, globus pallidus, entopeduncular nucleus and ventral globus pallidus, olfactory tubercle and islands of Calleja, diagonal band of Broca nucleus, nucleus basalis, and medial septal nucleus), diencephalon (ventrolateral preoptic, hypothalamic ventrolateral, and medial habenular nuclei), and brainstem (parabigeminal, laterodorsal tegmental, and pedunculopontine tegmental nuclei). These findings are discussed through both a functional and phylogenetic perspective.

Unilateral absence of mandibular condyle in a Bronze Age male skeleton from Portugal

In 2009, a pit burial dated to the Bronze Age was excavated in Monte do Gato de Cima 3 (Portugal). The purpose of this paper is to describe the pathological absence of the left mandibular condyle noted in an adult male skeleton and to discuss possible diagnoses, including subcondylar fracture, cystic defect, congenital absence, condylar aplasia and mandibular condylysis. The most likely explanation for the pathological alteration is subcondylar fracture with non-union. Although the occurrence of non-union and slight osteoarthritic alterations in the left glenoid fossa were evident, this mandible was likely functional, as can be inferred from dental wear and muscle attachment sites. This trauma probably occurred before adult age when remodelling capacity is still high. Thus, bones and muscles adequately compensated for the trauma and only minor asymmetry developed. Consequently, this injury seems not to have greatly influenced masticatory functions. This is in accordance with clinical data, which demonstrate that, in growing patients, conservative treatment (non-surgical) results in good remodelling and patient recovery. In addition, in the few paleopathological cases published, the healing capacity of these types of mandibular fractures seems to be good, as can be inferred by evidence from the bone.

[Pseudotumor cerebri associated with hypovitaminosis A, B6 and D. About two cases]

Idiopathic endocranial hypertension is infrequently associated with hypovitaminosis A and D. The case of an 8-year-old female with 24-hour blurred vision and bilateral papilledema is presented. Nuclear magnetic resonance was normal. Opening pressure of cerebrospinal fluid: 260 mmH2O. She presented vitamin A and D deficiency and started replacement therapy. The second case corresponds to a 12-year-old male with fever and odynophagia of 3 days. History of glomerulonephritis and overweight. He had bipalpebral edema and papilledema. Computed tomography scan of the orbit: increase of fluid in the sheath of both optic nerves. Nuclear magnetic resonance: intrasellar arachnoidocele. Opening pressure of cerebrospinal fluid: 400 mmH2O. He presented vitamin D and B6 deficiency and started replacement treatment. The elevation of intracranial pressure triggers compensation mechanisms that, when they fail, can compromise life or cause serious neurological disabilities. Recognizing the cause for an accurate therapeutic approach is key to reduce the morbidity and mortality associated with this pathology.

Repurposing itraconazole to the benefit of skin cancer treatment: A combined azole-DDAB nanoencapsulation strategy

In this work, we aimed at developing an improved topical SLN formulation combining itraconazole delivery with a coating layer of didodecyldimethylammonium bromide, thus repurposing the drug effectiveness by synergistic skin anticancer effectiveness. In order to obtain a stable SLN formulation with small homogeneously dispersed particles, a deep formulative study was developed screening three different solid lipids (Suppocire NB, Cetyl Palmitate and Dynasan 114) for the SLN preparation by the phase inversion temperature. A bluishcolored shade formulation, with homogeneous small particles size (<50 nm) was obtained only using Suppocire NB. The cytotoxicity of all SLN was tested after 24 h exposure against three adherent skin cell lines (A431, HaCaT and SK-MEL-5). Results demonstrate that both unloaded and drugloaded SLN did not significantly affect the cell viability of the non-tumoral HaCaT cell line, thus confirming the safe potential topical application of these formulations. A dose-dependent decrease in cell viability was observed for the tumoral cell lines, A431 and SK-MEL-5, with a significant reduction of the A431 cancer cell line viability. The drug molecule addition to the uncoated nanoparticles was able to increase of almost 20% the reduction of the viability of the cancer cells treated. Ours results demonstrate the potentiality of repurposing itraconazole activity by using the combined nanoencapsulation strategy with the positively charged coating layer on SLN, which can be further investigated as a promising stable and safe approach to significantly reduce the viability of skin cancer cells.

Efeito de Líquidos Alimentares e Escovação na Estabilidade de Cor de uma Cerâmica Vítrea de Dissilicato de Lítio

O objetivo do trabalho foi avaliar a estabilidade de cor de uma cerâmica vítrea de dissilicato de lítio submetida a imersão em líquidos alimentares e teste de escovação. Espécimes (n160) em cerâmica vítrea de dissilicato de lítio IPS E.max CAD HT Blocks, cor A2 foram divididos em dois grupos de acordo com o preparo de superfície – glazeamento (GG n80), polimento mecânico    (GP n80). Estes foram redistribuídos de acordo com os diferentes líquidos de imersão (n8) – água destilada (AD), café (CF), chá preto (CH), vinho tinto (VT), refrigerante de cola (CC) e associação com escovação (n8) - AD+Esc, CF+Esc, CH+Esc, VT+Esc, CC+Esc. A estabilidade de cor foi avaliada antes (T0) e após (T1) as imersões e escovação, simulando-se um período de 5 anos. Um espectrofotômetro portátil foi empregado para quantificar a diferença colorimétrica (OE) de cada amostra. Todas as soluções causaram alterações na cor das cerâmicas, e de forma semelhante independente do tratamento de superfície (p0,729). O maior manchamento foi provocado pelo vinho tinto (GG: p<0,001 GP: p0,004), com variações de cor (OE) de 2,61±0,52 e 2,22±0,43, respectivamente. A escovação simulada não influenciou nas alterações de estabilidade de cor observadas após as imersões (p>0,05). Conclui-se que, embora as mudanças de cor tenham ocorrido dentro de um nível clinicamente aceitável, a cerâmica de dissilicato de lítio está sujeita aos efeitos deletérios dos líquidos alimentares testados sofrendo alteração de cor, sendo que esse efeito não foi amenizado pela escovação.Palavras-chave: Dissilicato de Lítio. Glazeamento. Escovação Dentária.

Uso de Plasma Frio no Controle de Biofilme de Candida albicans em Próteses Dentárias de Resina Acrílica: Revisão de Literatura

O trabalho objetivou avaliar o uso do plasma frio no controle de biofilmes de Candida em próteses de resina acrílica. Realizou-se uma busca na base de dados Pubmed, utilizando as seguintes palavras-chave combinadas entre si: “cold plasma”, “Candida albicans” e “acrylic resins”, no período de 2010 a 2017. Foram encontrados 478 resultados na busca e selecionados 7 artigos científicos, utilizando como critério de inclusão: estudos in vitro e/ou clínico experimentais controlados, envolvendo a utilização de plasma frio em superfícies de resina acrílica e/ou que avaliaram crescimento de Candida albicans nestas. A literatura relata que o plasma frio, disponível em diferentes composições de gases, apresenta como mecanismo principal de ação aumentar a hidrofilia das superfícies em resina, fortificando ligações químicas e, assim, desfavorecendo a aderência inicial de Candida albicans, o que daria início ao processo de colonização – e futuro surgimento de infecção oral – por este fungo oportunista. Também aumenta a microdureza das próteses e, assim, a sua resistência à corrosão porém não exibe efeitos significantes sobre propriedades como rugosidade superficial, módulo de elasticidade e resistência flexural. Conclui-se que o uso do plasma pode ser promissora na prevenção da adesão fúngica às bases protéticas, sem alterar negativamente as propriedades físicas e mecânicas dos materiais envolvidos porém, há escassez na literatura de trabalhos que o compare com outros mecanismos anti-fúngicos e estudos clínicos a longo prazo.Palavras-chave: Cold Plasma. Candida albicans. Acrylic Resins.

Caracterização e Avaliação Histológica de Amostras Recobertas com Filmes de Carbono para Uso em Próteses Totais de ATM

Próteses articulares são fabricadas com ligas de Ti-6Al-4V ou Co-Cr-Mo, porém, a liberação de íons nestas ligas pode causar efeitos tóxicos. O revestimento de superfícies articulares com um “filme protetor“ visa aumentar a longevidade das próteses e evitar a liberação de íons causadores de hipersensibilidade, além de diminuir a dor, ocasionalmente provocada pela alteração da temperatura do metal. O filme de Diamond-Like Carbon (DLC) vem sendo pesquisado, devido sua biocompatibilidade, alta resistência ao desgaste e à corrosão, baixo coeficiente de atrito, inércia química e efeito bactericida. O objetivo deste estudo foi avaliar a neoformação óssea em amostras de liga Ti-6Al-4V recobertas com filme de DLC associados ou não a nanopartículas de prata (nAg). Após caracterização estrutural as amostras foram fixadas bilateralmente no ângulo da mandíbula de 30 coelhos. Quinze e 90 dias após a cirurgia, as amostras foram removidas junto ao osso, e novamente caracterizadas. Os filmes de DLC e DLC-Ag mostraram alta resistência elétrica e não sofreram alterações significativas no espectro Raman após exposição in vivo. No teste de Micro scratch test observou- se que os filmes aumentaram sua resistência mecânica após o teste in vivo. Em todos os animais, foi ocorreu neoformação óssea  na interface osso-amostra, caracterizando a osseointegração da mesma e não observou-se diferença estatística entre os grupos no mesmo período (p>0,05). Concluiu-se que os filmes de DLC e DLC-Ag reagem in vivo de forma semelhante à liga Ti-6Al-4V, que é considerada o padrão ouro para uso biomédico.Palavras-chave: Osseointegração. Carbono. Articulação Temporomandibular.

Evaluation of Respiration with Clark-Type Electrode in Isolated Mitochondria and Permeabilized Animal Cells

In many studies, the evaluation of mitochondrial function is critical to understand how disease conditions or xenobiotics alter mitochondrial function. One of the classic end points that can be assessed is oxygen consumption, which can be performed under controlled yet artificial conditions. Oxygen is the terminal acceptor in the mitochondrial respiratory chain, namely, at an enzyme called cytochrome oxidase, which produces water in the process and pumps protons from the matrix to the intermembrane space. Several techniques are available to measure oxygen consumption, including polarography with oxygen electrodes or fluorescent/luminescent probes. The present chapter will deal with the determination of mitochondrial oxygen consumption by means of the Clark-type electrode, which has been widely used in the literature and still remains to be a reliable technique. We focus our technical description in the measurement of oxygen consumption by isolated mitochondrial fractions and by permeabilized cells.

Nutritional impact on gene expression and competence of oocytes used to support embryo development and livebirth by cloning procedures in goats

Changes in the nutritional plan have been shown to affect oocyte quality, crucial to oocyte donors animals used in cloning. This study aimed to evaluate the impact of diets with increasing nutritional levels (maintenance diet=M; 1.3M; 1.6M; 1.9M) fed to goats for four weeks on follicular fluid composition, gene expression and oocyte competence used to cloning in goats. Donor females were superovulated for the retrieval of matured oocytes and physical measurements reported. After four weeks, groups receiving diets above maintenance increased thickness of subcutaneous adipose tissue and body weight, with higher values in 1.9M Group (P<0.05). Treatments did not affect follicular density, number of aspirated follicles, retrieved and matured oocytes. Animals from 1.3M group had lower (P<0.05) maturation rate (44.0%) and number of viable oocytes (65.3%) than M (68.8%) and 1.9M (76.0%). Follicular fluid glucose concentrations increased with nutritional levels (P=0.010), with a difference (P<0.05) between groups 1.9M (11.4±2.6mg/dL) and M (2.6±0.5mg/dL). The diet did not affect the expression of GDF9, BMP15, and BAX genes in oocytes, but BCL2 and apoptotic index were significantly higher (P<0.05) in the 1.3M and 1.6M groups than the other groups. Following the transfer of cloned embryos, one fetus was born live of a twin pregnancy in the 1.9M Group. The association between energy intake and oocyte quality suggests better nutritional use by oocytes when the maximum flow was used (1.9M), but the optimal feeding level in cloning still needs refinement.

The origin of high electrocatalytic activity of hydrogen peroxide reduction reaction by a g-C3N4/HOPG sensor

Graphitic carbon nitride (g-C₃N₄) was synthesized from a low-cost precursor by means of a thermal process. The product was characterized by several spectroscopic techniques and the crystallinity was analyzed by X-ray diffraction. In the manufacture of the sensor, g-C₃N₄ was chemically exfoliated and a film was placed on the surface of a Highly Oriented Pyrolytic Graphite (HOPG). We compared the electrocatalytic activities of g-C₃N₄/HOPG and pristine HOPG surfaces as sensors for H₂O₂ quantification in buffer solution at pH 7. The results indicate that the surface of g-C₃N₄/HOPG exhibits striking analytical stability as well as reproducibility, enabling a reliable and sensitive determination within the 0.12-120 μM interval with a detection limit of 0.12 μM. These results suggest that this g-C₃N₄ film is a really particularly good nano-structured material to be applied as a biosensor. Chemical and physical factors are responsible for the outstanding electrocatalytic activity observed. The N in the g-C₃N₄ allows huge uptake of H₂O₂ through the hydrogen-bonding interaction and the change in the electronic structure since the HOPG/g-C₃N₄ heterojunction favors the charge transfer process through the interface.

The population genomics of archaeological transition in west Iberia: Investigation of ancient substructure using imputation and haplotype-based methods

We analyse new genomic data (0.05–2.95x) from 14 ancient individuals from Portugal distributed from the Middle Neolithic (4200–3500 BC) to the Middle Bronze Age (1740–1430 BC) and impute genomewide diploid genotypes in these together with published ancient Eurasians. While discontinuity is evident in the transition to agriculture across the region, sensitive haplotype-based analyses suggest a significant degree of local hunter-gatherer contribution to later Iberian Neolithic populations. A more subtle genetic influx is also apparent in the Bronze Age, detectable from analyses including haplotype sharing with both ancient and modern genomes, D-statistics and Y-chromosome lineages. However, the limited nature of this introgression contrasts with the major Steppe migration turnovers within third Millennium northern Europe and echoes the survival of non-Indo-European language in Iberia. Changes in genomic estimates of individual height across Europe are also associated with these major cultural transitions, and ancestral components continue to correlate with modern differences in stature.

Recent ancient DNA work has demonstrated the significant genetic impact of mass migrations from the Steppe into Central and Northern Europe during the transition from the Neolithic to the Bronze Age. In Iberia, archaeological change at the level of material culture and funerary rituals has been reported during this period, however, the genetic impact associated with this cultural transformation has not yet been estimated. In order to investigate this, we sequence Neolithic and Bronze Age samples from Portugal, which we compare to other ancient and present-day individuals. Genome-wide imputation of a large dataset of ancient samples enabled sensitive methods for detecting population structure and selection in ancient samples. We revealed subtle genetic differentiation between the Portuguese Neolithic and Bronze Age samples suggesting a markedly reduced influx in Iberia compared to other European regions. Furthermore, we predict individual height in ancients, suggesting that stature was reduced in the Neolithic and affected by subsequent admixtures. Lastly, we examine signatures of strong selection in important traits and the timing of their origins.

Ibuprofen nanocrystals developed by 22 factorial design experiment: A new approach for poorly water-soluble drugs

The reduction of the particle size of drugs of pharmaceutical interest down to the nano-sized range has dramatically changed their physicochemical properties. The greatest disadvantage of nanocrystals is their inherent instability, due to the risk of crystal growth. Thus, the selection of an appropriate stabilizer is crucial to obtain long-term physicochemically stable nanocrystals. High pressure homogenization has enormous advantages, including the possibility of scaling up, lack of organic solvents and the production of small particles diameter with low polydispersity index. The sequential use of high shear homogenization followed by high pressure homogenization, can modulate nanoparticles’ size for different administration routes. The present study focuses on the optimization of the production process of two formulations composed of different surfactants produced by High Shear Homogenization followed by hot High Pressure Homogenization. To build up the surface response charts, a 2² full factorial design experiment, based on 2 independent variables, was used to develop optimized formulations. The effects of the production process on the mean particle size and polydispersity index were evaluated. The best ibuprofen nanocrystal formulations were obtained using 0.20% Tween 80 and 1.20% PVP K30 (F1) and 0.20% Tween 80 and 1.20% Span 80 (F2). The estimation of the long-term stability of the aqueous suspensions of ibuprofen nanocrystals was studied using the LUMISizer. The calculated instability index suggests that F1 was more stable when stored at 4 °C and 22 °C, whereas F2 was shown to be more stable when freshly prepared.

Targeting dendritic cells for the treatment of autoimmune disorders

In the last decades, it has been recognized that extracellular vesicles (EVs) are not only cell debris with no biological role, but instead they play a key role in information exchange between cells either in health and disease conditions. EVs exhibit indeed their biological role in a pleiotropic manner. They can modulate immune responses through the activation, transfer or removal of surface receptors on target cells, the removal of cytolytic components such as membrane attack complexes, and the transfer of signaling molecules/effectors, such as nucleic acid species, infectious particles, and oncogenes. Among the naturally-derived nanoparticles that have been developed in the last years, stimuli responsive exosomes drew special attention since they intrinsically possess many attributes of a desirable drug delivery system. Their small size allows them to bypass the mononuclear phagocytic system (MPS) clearance, thereby prolonging their circulation time for passive targeting to inflammatory tissues. Moreover, they can deliver their cargo directly into the cytosol, avoiding the lysosomal/endosomal pathway and thus, increasing the transfection efficiency when they are used as gene delivery systems. of This review offers the state of the art knowledge on the physiology and properties of EVs, namely, apoptotic vesicles, microvesicles and exosomes as innovative drug delivery systems for gene therapy, with a special focus on targeting dendritic cells for the treatment of autoimmune disorders.

Sedentary behavior and compensatory mechanisms in response to different doses of exercise-a randomized controlled trial in overweight and obese adults

BACKGROUND/OBJECTIVES

To examine compensatory changes in sedentary behavior (SB) and light-intensity physical activities (LIPA) in response to a 22-week exercise training program in overweight/obese adults; and to determine if different forms of exercise training and physical activity recommendations interact with these compensatory changes.

SUBJECTS/METHODS

Eighty-nine overweight and obese individuals (body mass index (BMI): 25-34.9 kg/m², 48% males), aged 18-50 years, were randomized into four intervention groups (strength, endurance, combined strength + endurance and physical activity recommendations) with a 25-30% caloric restriction of total daily energy expenditure for 22 weeks. Energy expenditure was measured by accelerometry before, during and after the program.

RESULTS

LIPA increased significantly (P<0.001) after three months and at the end of intervention compared to baseline (pre: 281±9 min; 3 months: 303±9 min; post: 312±8 min). SB percentage decreased by 5.3 at the end of the intervention (P=0.002). No interactions were observed between groups or sexes. Significant correlations were found between SB and body weight, fat mass, android fat mass and lean body mass before and after the intervention (P<0.05). LIPA was also significantly correlated with all these body composition variables in the pre-intervention, but only correlated with body weight at the end of intervention.

CONCLUSIONS

There were no compensatory changes after a combined exercise and diet program; where minutes in LIPA increased and %SB decreased after the program, without differences among exercise modes. Greater physical activity levels can contribute to a better percentage and distribution of body tissues.

Mendelian inheritance, genetic linkage, and genotypic disequilibrium for nine microsatellite loci in Cariniana estrellensis (Raddi) Kuntze (Lecythidaceae)

Cariniana estrellensis is one of the largest trees found in Brazilian tropical forests. The species is typical of advanced stages of succession, characteristic of climax forests, and essential in genetic conservation and environmental restoration plans. In this study, we assessed Mendelian inheritance, genetic linkage, and genotypic disequilibrium in nine microsatellite loci for a C. estrellensis population. We sampled and genotyped 285 adult trees and collected seeds from 20 trees in a fragmented forest landscape in Brazil. Based on maternal genotypes and their seeds, we found no deviation from the expected 1:1 Mendelian segregation and no genetic linkage between pairwise loci. However, for adults, genotypic disequilibrium was detected for four pairs of loci, suggesting that this result was not caused by genetic linkage. Based on these results, we analyzed microsatellite loci that are suitable for use in population genetic studies assessing genetic diversity, mating system, and gene flow in C. estrellensis populations.

Solid lipid nanoparticles affect microbial colonization and enzymatic activity throughout the decomposition of alder leaves in freshwater microcosms

Solid lipid nanoparticles (SLNs) are used as carriers for drug delivery, and are high biocompatible and designed to endure in the host organism. Despite its current industrial production is low, many of these substances are available on the market, and much more are in the production pipeline. As a result, many of them will end in aquatic systems raising the question whether they can pose a risk to aquatic biota and the associated ecological processes. Microbial decomposers of plant litter, play a key role in forested streams being responsible for the energy flow between terrestrial and aquatic environments. Here, we investigated the effects of SLNs on alder leaf litter decomposition by aquatic microbes. Alder leaves were immersed in a stream of Northeast Portugal to allow microbial colonization before being exposed in microcosms of two types of SLNs at two concentrations for 42 days. Results showed that rates of leaf decomposition decreased with exposure to SLNs. Bacterial biomass was not inhibited by SLNs, and cultivable fungi densities remained constant (SLN-A) or increased (SLN-C) compared with control microcosms. The type and concentration of SLNs influenced differently the leaf colonization by fungi as well as fungal sporulation rate. These effects were accompanied by changes in the community extraenzymatic profile: the activities of alkaline phosphatase, acidic phosphatase, Naphthol-AS-BI-phosphohydrolase (P cycle) and lipases increased in the SLNs microcosms. This study provided the first evidence of the adverse effects of the release of SLNs to streams on leaf litter decomposition. Those effects seem to depend on the composition and concentration of SLNs, as well on the microbial target group, or enzyme. Thus, prior to massive industrial production of these nanomaterials, some measures should be taken to avoid environmental impact affecting the microbial communities responsible for detritus decomposition.