Infections are one of the main reasons for removal of implants from patients, and usually need difficult and expensive treatments. Staphylococcus aureus and Staphylococcus epidermidis are the most ...frequently detected pathogens. We reviewed the epidemiology and pathogenesis of implant-related infections. Relevant studies were identified by electronic searching of the following databases: PubMed, ScienceDirect, Academic Google, and CAPES Journal Portal. This review reports epidemiological studies of implant infections caused by S. aureus and S. epidermidis. We discuss some methodologies used in the search for new compounds with antibiofilm activity and the main strategies for biomaterial surface modifications to avoid bacterial plaque formation and consequent infection. S. aureus and S. epidermidis are frequently involved in infections in catheters and orthopaedic/breast implants. Different methodologies have been used to test the potential antibiofilm properties of compounds; for example, crystal violet dye is widely used for in-vitro biofilm quantification due to its low cost and good reproducibility. Changes in the surface biomaterials are necessary to prevent biofilm formation. Some studies have investigated the immobilization of antibiotics on the surfaces of materials used in implants. Other approaches have been used as a way to avoid the spread of bacterial resistance to antimicrobials, such as the functionalization of these surfaces with silver and natural compounds, as well as the electrical treatment of these substrates.
Conventionally, evolution has always been described in terms of species. The Chemistry of Evolution takes a novel, not to say revolutionary, approach and examines the evolution of chemicals and the ...use and degradation of energy, coupled to the environment, as the drive behind it. The authors address the major changes of life from bacteria to man in a systematic and unavoidable sequence, reclassifying organisms as chemotypes. Written by the authors of the bestseller The Biological Chemistry of the Elements - The Inorganic Chemistry of Life (Oxford University Press, 1991), the clarity and precision of The Chemistry of Evolution plainly demonstrate that life is totally interactive with the environment. This exciting theory makes this work an essential addition to the academic and public library.* Provides a novel analysis of evolution in chemical terms * Stresses Systems Biology * Examines the connection between life and the environment, starting with the 'big bang' theory * Reorientates the chemistry of life by emphasising the need to analyse the functions of 20 chemical elements in all organisms
This living systematic review aims to summarize evidence on the prevalence of oral signs and symptoms in patients with COVID-19. The review was reported per the PRISMA checklist, and the literature ...search was conducted in 6 databases and in gray literature. Studies published in any language mentioning oral symptoms and signs in patients with COVID-19 were included. The risk of bias was assessed by the Joanna Briggs Institute appraisal tools. The certainty of evidence was evaluated through GRADE assessment. After a 2-step selection, 40 studies were included: 33 cross-sectional and 7 case reports. Overall, 10,228 patients (4,288 males, 5,770 females, and 170 unknown) from 19 countries were assessed. Gustatory impairment was the most common oral manifestation, with a prevalence of 45% (95% CI, 34% to 55%; I2 = 99%). The pooled eligible data for different taste disorders were 38% for dysgeusia and 35% for hypogeusia, while ageusia had a prevalence of 24%. Taste disorders were associated with COVID-19 (odds ratio OR, 12.68; 95% CI, 6.41 to 25.10; I2 = 63%; P < 0.00001), mild/moderate severity (OR, 2.09; 95% CI, 1.25 to 3.49; I2 = 66%; P = 0.005), and female patients (OR, 1.64; 95% CI, 1.23 to 2.17; I2 = 70%; P = 0.0007). Oral mucosal lesions presented multiple clinical aspects, including white and erythematous plaques, irregular ulcers, small blisters, petechiae, and desquamative gingivitis. Tongue, palate, lips, gingiva, and buccal mucosa were affected. In mild cases, oral mucosal lesions developed before or at the same time as the initial respiratory symptoms; however, in those who required medication and hospitalization, the lesions developed approximately 7 to 24 d after onset symptoms. Therefore, taste disorders may be common symptoms in patients with COVID-19 and should be considered in the scope of the disease’s onset and progression. Oral mucosal lesions are more likely to present as coinfections and secondary manifestations with multiple clinical aspects (PROSPERO CRD42020184468).
Abnormal hypothalamic/posterior pituitary development appears to be a major determinant of pituitary stalk interruption syndrome (PSIS). The observation of familial cases and associated congenital ...abnormalities suggests a genetic basis. Single‐gene mutations explain less than 5% of the cases, and whole exome sequencing has shown heterogeneous results. The present study aimed to assess copy number variation (CNV) using array‐based comparative genomic hybridization (aCGH) in patients with non‐syndromic PSIS and comprehensively review data from the literature on CNV analysis in congenital hypopituitarism (CH) patients. Twenty‐one patients with sporadic CH from our outpatient clinics presented with ectopic posterior pituitary (EPP) and no central nervous system abnormalities on magnetic resonance image (MRI) or any other malformations on physical examination at presentation were enrolled in the study. aCGH using a whole‐genome customized 400K oligonucleotide platform was performed in our patients. For the literature review, we searched for case reports of patients with CH and CNV detected by either karyotype or aCGH reported in PubMed up to November 2021. Thirty‐five distinct rare CNVs were observed in 18 patients (86%) and two of them (6%) were classified as pathogenic: one deletion of 1.8 Mb in chromosome 17 (17q12) and one deletion of 15 Mb in chromosome 18 (18p11.32p11.21), each one in a distinct patient. In the literature review, 67 pathogenic CNVs were published in 83 patients with CH, including the present study. Most of these patients had EPP (78% out of the 45 evaluated by sellar MRI) and were syndromic (70%). The most frequently affected chromosomes were X, 18, 20 and 1. Our study has found that CNV can be a mechanism of genetic abnormality in non‐syndromic patients with CH and EPP. In future studies, one or more genes in those CNVs, both pathogenic and variant of uncertain significance, may be considered as good candidate genes.
Pituitary development takes place from two embryonal apposed ectodermal tissues. The anterior pituitary (AP), so‐called adenohypophysis, forms from an upward protrusion of the epithelium of the roof of the mouth (Rathke's pouch, Rp) that extends toward the posterior pituitary (PP), or neurohypophysis, which grows downward by a ventral evagination from the diencephalon (de) of the developing brain. PP is attached to the infundibular (inf) stalk, which arises from an anlage in the floor of the third ventricle. Ectopic posterior pituitary (EPP) is the hallmark of pituitary stalk interruption syndrome (PSIS), which is mainly associated with AP endocrine defects because of its early neural induction of the Rp. However, pituitary‐development single‐gene mutations explain less than 5% of the cases, and whole exome sequencing still presents heterogeneous results. Our findings demonstrate the contribution of searching for copy number variation (CNV) using array‐based comparative genomic hybridization (aCGH) in patients with PSIS, suggesting that CNV can be an additional mechanism of developmental abnormality in non‐syndromic patients with congenital hypopituitarism and ectopic posterior pituitary.
Modern light generation technology offers extraordinary capabilities for sculpting light pulses, with full control over individual electric field oscillations within each laser cycle1–3. These ...capabilities are at the core of lightwave electronics—the dream of ultrafast lightwave control over electron dynamics in solids on a sub-cycle timescale, aiming at information processing at petahertz rates4–8. Here, bringing the frequency-domain concept of topological Floquet systems9,10 to the few-femtosecond time domain, we develop a theoretical method that can be implemented with existing technology, to control the topological properties of two-dimensional materials on few-femtosecond timescales by controlling the sub-cycle structure of non-resonant driving fields. We use this method to propose an all-optical, non-element-specific technique, physically transparent in real space, to coherently write, manipulate and read selective valley excitation using fields carried in a wide range of frequencies and on timescales that are orders of magnitude shorter than the valley lifetime, crucial for the implementation of valleytronic devices11,12.A method to control the topological properties of two-dimensional (2D) materials on few-femtosecond timescales is proposed. By controlling the sub-cycle structure of non-resonant driving fields, it may be possible to coherently write, manipulate and read selective valley excitation.
OBJECTIVE—Recent proteomic studies have identified multiple proteins that coisolate with human HDL. We hypothesized that distinct clusters of protein components may distinguish between ...physicochemically-defined subpopulations of HDL particles, and that such clusters may exert specific biological function(s).
METHODS AND RESULTS—We investigated the distribution of proteins across 5 physicochemically-defined particle subpopulations of normolipidemic human HDL (HDL2b, 2a, 3a, 3b, 3c) fractionated by isopycnic density gradient ultracentrifugation. Liquid chromatography/electrospray mass spectrometry identified a total of 28 distinct HDL-associated proteins. Using an abundance pattern analysis of peptide counts across the HDL subfractions, these proteins could be grouped into 5 distinct classes. A more in-depth correlational network analysis suggested the existence of distinct protein clusters, particularly in the dense HDL3 particles. Levels of specific HDL proteins, primarily apoL-I, PON1, and PON3, correlated with the potent capacity of HDL3 to protect LDL from oxidation.
CONCLUSIONS—These findings suggest that HDL is composed of distinct particles containing unique (apolipo)protein complements. Such subspeciation forms a potential basis for understanding the numerous observed functions of HDL. Further work using additional separation techniques will be required to define these species in more detail.
The sub-laser-cycle timescale of the electronic response to strong fields enables attosecond dynamical imaging in atoms, molecules and solids1–4, with optical tunnelling and high-harmonic generation ...the hallmarks of attosecond optical spectroscopy2,5–7. Topological insulators are intimately linked with electron dynamics, as manifested via the chiral edge currents8, but it is unclear if and how topology leaves its mark on optical tunnelling and sub-cycle electronic response. Here, we identify distinct bulk topological effects on directionality and timing of currents arising during electron injection into conduction bands. We show that electrons tunnel differently in trivial and topological insulators, for the same band structure, and identify the key role of the Berry curvature in this process. These effects map onto topologically dependent attosecond delays and helicities of emitted harmonics that record the phase diagram of the system. Our findings create new roadmaps in studies of topological systems, building on the ubiquitous properties of the sub-laser-cycle strong-field response—a unique mark of attosecond science.
We examined the potential growth of clonal Eucalyptus plantations at eight locations across a 1000+ km gradient in Brazil by manipulating the supplies of nutrients and water, and altering the ...uniformity of tree sizes within plots. With no fertilization or irrigation, mean annual increments of stem wood were about 28% lower (16.2
Mg
ha
−1
yr
−1, about 33
m
3
ha
−1
yr
−1) than yields achieved with current operational rates of fertilization (22.6
Mg
ha
−1
yr
−1, about 46
m
3
ha
−1
yr
−1). Fertilization beyond current operational rates did not increase growth, whereas irrigation raised growth by about 30% (to 30.6
Mg
ha
−1
yr
−1, about 62
m
3
ha
−1
yr
−1). The potential biological productivity (current annual increment) of the plantations was about one-third greater than these values, if based only on the period after achieving full canopies. The biological potential productivity was even greater if based only on the full-canopy period during the wet season, indicating that the maximum biological productivity across the sites (with irrigation, during the wet season) would be about 42
Mg
ha
−1
yr
−1 (83
m
3
ha
−1
yr
−1). Stands with uniform structure (trees in plots planted in a single day) showed 13% greater growth than stands with higher heterogeneity of tree sizes (owing to a staggered planting time of up to 80 days). Higher water supply increased growth and also delayed by about 1 year the point where current annual increment and mean annual increment intersected, indicating opportunities for lengthening rotations for more productive treatments as well as the influence of year-to-year climate variations on optimal rotations periods. The growth response to treatments after canopy closure (mid-rotation) related well with full-rotation responses, offering an early opportunity for estimating whole-rotation yields. These results underscore the importance of resource supply, the efficiency of resource use, and stand uniformity in setting the bounds for productivity, and provide a baseline for evaluating the productivity achieved in operational plantations. The BEPP Project showed that water supply is the key resource determining levels of plantation productivity in Brazil. Future collaboration between scientists working on silviculture and genetics should lead to new insights on the mechanisms connecting water and growth, leading to improved matching of sites, clones, and silviculture.
The creation of nanoscale organic–inorganic hybrid coatings with uniform architecture and high surface area, while maintaining their structural and morphological integrity, remains a significant ...challenge in the field. In this study, we present a novel solution, by utilizing Atomic/Molecular Layer Deposition (ALD/MLD) to coat patterned vertically aligned carbon nanotube micropillars with a conformal amorphous layer of Fe-NH2TP, which is a trivalent iron complex complexed with 2-amino terephthalate. The effectiveness of the coating is verified through multiple analytical techniques, including high-resolution transmission electron microscopy, scanning transmission electron microscopy, grazing incidence X-ray diffraction, and Fourier transform infrared spectroscopy. The Fe-NH2TP hybrid film exhibits hydrophobic properties, as confirmed by water contact angle measurements. Our findings contribute to advancing the understanding of how to grow high-quality one-dimensional materials using ALD/MLD and hold promise for future research in this area.
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