Abstract
BACKGROUND
Endometriosis is a gynaecological hormone-dependent disorder that is defined by histological lesions generated by the growth of endometrial-like tissue out of the uterus cavity, ...most commonly engrafted within the peritoneal cavity, although these lesions can also be located in distant organs. Endometriosis affects ~10% of women of reproductive age, frequently producing severe and, sometimes, incapacitating symptoms, including chronic pelvic pain, dysmenorrhea and dyspareunia, among others. Furthermore, endometriosis causes infertility in ~30% of affected women. Despite intense research on the mechanisms involved in the initial development and later progression of endometriosis, many questions remain unanswered and its aetiology remains unknown. Recent studies have demonstrated the critical role played by the relationship between the microbiome and mucosal immunology in preventing sexually transmitted diseases (HIV), infertility and several gynaecologic diseases.
OBJECTIVE AND RATIONALE
In this review, we sought to respond to the main research question related to the aetiology of endometriosis. We provide a model pointing out several risk factors that could explain the development of endometriosis. The hypothesis arises from bringing together current findings from large distinct areas, linking high prenatal exposure to environmental endocrine-disrupting chemicals with a short anogenital distance, female genital tract contamination with the faecal microbiota and the active role of genital subclinical microbial infections in the development and clinical progression of endometriosis.
SEARCH METHODS
We performed a search of the scientific literature published until 2019 in the PubMed database. The search strategy included the following keywords in various combinations: endometriosis, anogenital distance, chemical pollutants, endocrine-disrupting chemicals, prenatal exposure to endocrine-disrupting chemicals, the microbiome of the female reproductive tract, microbiota and genital tract, bacterial vaginosis, endometritis, oestrogens and microbiota and microbiota–immune system interactions.
OUTCOMES
On searching the corresponding bibliography, we found frequent associations between environmental endocrine-disrupting chemicals and endometriosis risk. Likewise, recent evidence and hypotheses have suggested the active role of genital subclinical microbial infections in the development and clinical progression of endometriosis. Hence, we can envisage a direct relationship between higher prenatal exposure to oestrogens or estrogenic endocrine-disrupting compounds (phthalates, bisphenols, organochlorine pesticides and others) and a shorter anogenital distance, which could favour frequent postnatal episodes of faecal microbiota contamination of the vulva and vagina, producing cervicovaginal microbiota dysbiosis. This relationship would disrupt local antimicrobial defences, subverting the homeostasis state and inducing a subclinical inflammatory response that could evolve into a sustained immune dysregulation, closing the vicious cycle responsible for the development of endometriosis.
WIDER IMPLICATIONS
Determining the aetiology of endometriosis is a challenging issue. Posing a new hypothesis on this subject provides the initial tool necessary to design future experimental, clinical and epidemiological research that could allow for a better understanding of the origin of this disease. Furthermore, advances in the understanding of its aetiology would allow the identification of new therapeutics and preventive actions.
The biological cycle of Nosema spp. in honeybees depends on temperature. When expressed as total spore counts per day after infection, the biotic potentials of Nosema apis and N. ceranae at 33°C were ...similar, but a higher proportion of immature stages of N. ceranae than of N. apis were seen. At 25 and 37°C, the biotic potential of N. ceranae was higher than that of N. apis. The better adaptation of N. ceranae to complete its endogenous cycle at different temperatures clearly supports the observation of the different epidemiological patterns.
Determining SARS-CoV-2 viral infectivity is crucial for patient clinical assessment and isolation decisions. We assessed subgenomic RNA (sgRNA) as a surrogate marker of SARS-CoV-2 infectivity in ...SARS-CoV-2-positive reverse transcription PCR (RT-PCR) respiratory samples (
= 105) in comparison with viral culture as the reference standard for virus replication. sgRNA and viral isolation results were concordant in 99/105 cases (94%), indicating highly significant agreement between the two techniques (Cohen's kappa coefficient 0.88, 95% confidence interval CI 0.78 to 0.97,
< 0.001). sgRNA RT-PCR showed a sensitivity of 97% and a positive predictive value of 94% to detect replication-competent virus, further supporting sgRNA as a surrogate marker of SARS-CoV-2 infectivity. sgRNA RT-PCR is an accurate, rapid, and affordable technique that can overcome culture and cycle threshold (
) value limitations and be routinely implemented in hospital laboratories to detect viral infectivity, which is essential for optimizing patient monitoring, the efficacy of treatments/vaccines, and work reincorporation policies, as well as for safely shortening isolation precautions.
The epidermal growth factor receptors EGFR and HER2 are the main targets for tyrosine kinase inhibitors (TKIs). The quinazoline derivative lapatinib (LAP) is used since 2007 as dual TKI in the ...treatment of metastatic breast cancer and currently, it is used as an oral anticancer drug for the treatment of solid tumors such as breast and lung cancer. Although hepatotoxicity is its main side effect, it makes sense to investigate the ability of LAP to induce photosensitivity reactions bearing in mind that BRAF (serine/threonine-protein kinase B-Raf) inhibitors display a considerable phototoxic potential and that afloqualone, a quinazoline-marketed drug, causes photodermatosis. Metabolic bioactivation of LAP by CYP3A4 and CYP3A5 leads to chemically reactive
N
-dealkylated (
N
-LAP) and
O
-dealkylated (
O
-LAP) derivatives. In this context, the aim of the present work is to explore whether LAP and its
N
- and
O
-dealkylated metabolites can induce photosensitivity disorders by evaluating their photo(geno)toxicity through in vitro studies, including cell viability as well as photosensitized protein and DNA damage. As a matter of fact, our work has demonstrated that not only LAP, but also its metabolite
N
-LAP have a clear photosensitizing potential. They are both phototoxic and photogenotoxic to cells, as revealed by the 3T3 NRU assay and the comet assay, respectively. By contrast, the
O
-LAP does not display relevant photobiological properties. Remarkably, the parent drug LAP shows the highest activity in membrane phototoxicity and protein oxidation, whereas
N
-LAP is associated with the highest photogenotoxicity, through oxidation of purine bases, as revealed by detection of 8-Oxo-dG.
The aim of this study was to evaluate the impact on muscle strength, aerobic fitness and body composition, of replacing the physical education (PE) class of Colombian adolescents with resistance or ...aerobic training. 120 tanner stage 3 adolescents attending a state school were randomized to resistance training, aerobic training, or a control group who continued to attend a weekly 2- hour PE class for 16 weeks. The resistance training and aerobic training groups participated in twice weekly supervised after-school exercise sessions of < 1 hour instead of their PE class. Sum of skinfolds, lean body mass (bioelectrical impedance analysis), muscular strength (6 repetition maximum (RM)) bench press, lateral pulldown and leg press) and estimated cardiorespiratory fitness (multistage 20 meter shuttle run) were assessed at pre and post intervention. Complete data were available for n = 40 of the resistance training group, n = 40 of the aerobic training group and n = 30 PE (controls). Resistance training attenuated increases in sum of skinfolds compared with controls (d = 0.27, 0.09-0.36). We found no significant effect on lean body mass. Resistance training produced a positive effect on muscle strength compared with both controls (d = 0.66 .49-.86) and aerobic training (d = 0.550.28-0.67). There was a positive effect of resistance training on cardiorespiratory fitness compared with controls (d = 0.04 -0.10-0.12) but not compared with aerobic training (d = 0.24 0.10-0.36). Replacing a 2-hour PE class with two 1 hour resistance training sessions attenuated gains in subcutaneous adiposity, and enhanced muscle strength and aerobic fitness development in Colombian youth, based on a median attendance of approximately 1 session a week. Further research to assess whether adequate stimuli for the development of muscular fitness exists within current physical education provision is warranted.
Defective few-layered graphene mesostructures (DFLGMs) are produced from graphite flakes by high-energy milling processes. We obtain an accurate control of the generated mesostructures, as well as of ...the amount and classification of the structural defects formed, providing a functional material for microwave absorption purposes. Working under far-field conditions, competitive values of minimum reflection loss coefficient (RLmin) = −21.76 dB and EAB = 4.77 dB are achieved when DFLGMs are immersed in paints at a low volume fraction (1.95%). One step forward is developed by combining them with the excellent absorption behavior that offers amorphous Fe73.5Si13.5B9Cu1Nb microwires (MWs), varying their filling contents, which are below 3%. We obtain a RLmin improvement of 47% (−53.08 dB) and an EAB enhancement of 137% (4 dB) compared to those obtained by MW-based paints. Furthermore, a f min tunability is demonstrated, maintaining similar RLmin and EAB values, irrespective of an ideal matching thickness. In this scenario, the Maxwell-Garnet standard model is valid, and dielectric losses mainly come from multiple reflections, interfacial and dielectric polarizations, which greatly boost the microwave attenuation of MWs. The present concept can remarkably enhance not only the MW attenuation but can also apply to other microwave absorption architectures of technological interest by adding low quantities of DFLGMs.
In this study, a two-step surfactant sol-gel strategy is developed to synthesize Co particles with confined sizes in the nanoscale using organic precursors. This approach does not require the use of ...vacuum techniques or strong reducing atmospheres, making it a simple approach economically attractive. The strategy involves the generation of few-layered graphene shells to provide chemical stability, prevent oxidation and aggregation tendencies. Additionally, the study investigates the use of precursors based on nitrates and acetates, exploring their structural and magnetic properties in densified samples. Remarkably, magnetic properties are competitive for both approaches, with coercivities reaching up to 300 Oe and saturation magnetization of ∼60 and ∼80 emu/g for samples based on nitrates and acetates prepared at 650 °C, respectively. However, it is observed that smaller and more uniformly sized nanoparticles (around ∼10 nm) are obtained with nitrate-based precursors due to an effective ligand decomposition process. Therefore, this chemical approach offers effective nanoscale confinement with intriguing magnetic properties through a cost-effective and reproducible synthesis.
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•Co@few-layered graphene nanostructures are achieved by cost-effective sol-gel method.•Reduced particle size distributions are obtained with nitrate-based Co precursor.•Saturation magnetization values between 60 and 80 emu/g are reached.•Nanostructures show ferromagnetic soft magnetic properties at room temperature.•Carbon incorporation in Co nanoparticles is suggested by XRD and XAS analyses.
We explore a simple and optimized approach for obtaining magnetic nanoparticle-carbon composites by a novel one-pot sol-gel method. In them, various metal cations ratios of Fe3+ and Co2+ are ...evaluated. The ratio of Fe:Co is a critical parameter that governs the presence of different crystalline phases with tailored magnetic properties. Interestingly, the smallest introduction of Co into the synthesis (19Fe:1Co) provides an abrupt emergence of the body-centered cubic (bcc) Fe-Co alloy, instead of the orthorhombic Pnma structure characteristic of the Fe3C intermetallic compound (1Fe:0Co). Advanced structural and electronic characterizations reveal the formation of Fe-Co/Co-ferrite core/shell nanoparticle structures embedded in a carbon matrix. The sphere-like nanoparticles range from 10 to 45 nm and the shells show a spinel structure with a thickness of 2–3 nm. In addition, X-ray absorption spectroscopy unveils that the oxidation state of Fe and Co cations is close to zero, demonstrating their predominant metallic character. The magnetic properties can be modulated by a precise control of the alloy composition varying the Co content, displaying saturation magnetization values close to ∼137 emu/g. The nanoparticles are mainly single magnetic domain with a considerable coercive field (∼450 Oe), higher than those reported in the literature for Fe-Co nanoparticles. This semi-hard character is due to a notable spring exchange effect emerged by passivating the surface of Fe-Co-bcc cores with a thin Co-ferrite-like shell.
•Sol-gel route for the synthesis of Fe-Co alloy/Co-ferrite core/shell nanoparticles.•Magnetic composite of nanoparticles supported on a carbon matrix.•Semihard magnetic properties by an effective spring-exchange interaction.•Low thickness of the Co-ferrite shell and elevated saturation magnetization.
•A novel sub-ppm NO2 gas sensor based on a few-layered mesoporous graphene (FLMG).•Few-layered mesoporous graphene is optimized at 100 min by a high-energy ball milling.•The room-temperature sensor ...exhibited high sensitivity, low cost and simple fabrication.•FLMG-based sensor shows an insignificant NH3 and humidity interference.
Few-layered mesoporous graphene (FLMG) is employed as a sensing material to develop an innovative and high-sensitivity room temperature NO2 sensor through a simple manufacturing process. For this purpose, sensing material is optimized at 100 min by a high-energy milling process where natural graphite is used as a precursor: it is an inexpensive, sustainable and suitable active material. The large number of defects created and the enhanced degree of mesoporosity produced during the milling process determine the physical principles of operation of the designed device. NO2 gas sensing tests reveal an improved and selective performance with a change in resistance of ∼16 % at 0.5 ppm under ultraviolet photo-activation, establishing a detection limit around ∼25 ppb. Interestingly, the response of the developed sensor to humidity is independent in the measured range (0–33 % relative humidity at 25 °C) and the dependency to the presence of NH3 is rather poor as well (∼1.5 % at 50 ppm).
Microwave power absorption by a two‐layer system deposited on a metallic surface is studied in the experimental setup emulating the response to a radar signal. Layers containing hexaferrite and iron ...powder in a dried paint of thickness under 1 mm are used. The data is analyzed within a theoretical model derived for a bilayer system from the transmission line theory. A good agreement between experimental and theoretical results is found. The advantage of using a bilayer system over a single‐layer system is demonstrated. How the maximum microwave absorption (minimum reflection) can be achieved through the optimization of the filling factors and thicknesses of the two layers is shown.
This work reports experimental and modeling results of single and bi‐layered systems with microwave‐absorbing properties. Layers containing hexaferrite and iron powder in paint are prepared and measured under real radar conditions in an anechoic chamber. The data is analyzed within a theoretical model derived for a bilayer system from the transmission line theory with very good agreement.
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