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Lipid transfer proteins (LTPs) are key players in cellular homeostasis and regulation, as they coordinate the exchange of lipids between different cellular organelles. Despite their importance, our mechanistic understanding of how LTPs function at the molecular level is still in its infancy, mostly due to the large number of existing LTPs and to the low degree of conservation at the sequence and structural level. In this work, we use molecular simulations to characterize a representative dataset of lipid transport domains (LTDs) of 12 LTPs that belong to 8 distinct families. We find that despite no sequence homology nor structural conservation, the conformational landscape of LTDs displays common features, characterized by the presence of at least 2 main conformations whose populations are modulated by the presence of the bound lipid. These conformational properties correlate with their mechanistic mode of action, allowing for the interpretation and design of experimental strategies to further dissect their mechanism. Our findings indicate the existence of a conserved, fold-independent mechanism of lipid transfer across LTPs of various families and offer a general framework for understanding their functional mechanism.
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The organelles of eukaryotic cells differ in their membrane lipid composition. This heterogeneity is achieved by the localization of lipid synthesizing and modifying enzymes to specific compartments, as well as by intracellular lipid transport that utilizes vesicular and non-vesicular routes to ferry lipids from their place of synthesis to their destination. For instance, the major and essential phospholipids, phosphatidylethanolamine (PE) and phosphatidylcholine (PC), can be produced by multiple pathways and, in the case of PE, also at multiple locations. However, the molecular components that underlie lipid homeostasis as well as the routes allowing their distribution remain unclear. Here, we present an approach in which we simplify and rewire yeast phospholipid synthesis by redirecting PE and PC synthesis reactions to distinct subcellular locations using chimeric enzymes fused to specific organelle targeting motifs. In rewired conditions, viability is expected to depend on homeostatic adaptation to the ensuing lipostatic perturbations and on efficient interorganelle lipid transport. We therefore performed genetic screens to identify factors involved in both of these processes. Among the candidates identified, we find genes linked to transcriptional regulation of lipid homeostasis, lipid metabolism, and transport. In particular, we identify a requirement for Csf1-an uncharacterized protein harboring a Chorein-N lipid transport motif-for survival under certain rewired conditions as well as lipidomic adaptation to cold, implicating Csf1 in interorganelle lipid transport and homeostatic adaptation.
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Lipídeos de Membrana , Organelas , Transporte Biológico , Homeostase , Metabolismo dos Lipídeos/genética , Lipídeos de Membrana/genética , Lipídeos de Membrana/metabolismo , Organelas/metabolismo , Fosfolipídeos/genética , Fosfolipídeos/metabolismoRESUMO
BACKGROUND: Perfluoroalkyl and poly-fluoroalkyl substances (PFAS) are pervasive environmental pollutants and emerging risk factors for reproductive health. Although epidemiological evidence supports the link between these substances and male infertility, their specific effects on male fertility remain poorly understood. OBJECTIVES: Investigate the effect of perfluorooctane sulfonic acid (PFOS), the most prevalent and prominent PFAS, on bull sperm protein phosphorylation, a post-translational modification process governing sperm functionality and fertility. METHODS: We exposed bull sperm to PFOS at 10 µM (average population level) and 100 µM (high-exposure level), and analyzed global proteome and phosphoproteome profile by TMT labeling and NanoLC-MS/MS. We also measured sperm fertility functions by flow cytometry. RESULTS: PFOS at 10 µM altered sperm proteins linked to spermatogenesis and chromatin condensation, while at 100 µM, PFOS affected proteins associated with motility and fertility. We detected 299 phosphopeptides from 116 proteins, with 45 exhibiting differential expression between control and PFOS groups. PFOS dysregulated phosphorylation of key proteins (ACRBP, PRKAR2A, RAB2B, SPAG8, TUBB4B, ZPBP, and C2CD6) involved in sperm capacitation, acrosome reaction, sperm-egg interaction, and fertilization. PFOS also affected phosphorylation of other proteins (AQP7, HSBP9, IL4I1, PRKAR1A, and CCT8L2) related to sperm stress resistance and cryotolerance. Notably, 4 proteins (PRM1, ACRBP, TSSK1B, and CFAP45) exhibited differential regulation at both the proteomic and phosphoproteomic levels. Flow cytometric analysis confirmed that PFOS increased protein phosphorylation in sperm as well as reduced sperm motility, viability, calcium, and membrane potential and increased mitochondrial ROS in a dose-dependent manner. CONCLUSIONS: This study shows that PFOS exposure adversely impacts phosphorylation of proteins critical for bull sperm function and fertilization. Moreover, the concentration of PFOS influences the severity of these effects. The comprehensive bull sperm phosphoproteomics data from this study can help us understand the molecular mechanisms of environmental exposure-related male infertility.
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OBJECTIVES: Anaemia during pregnancy is a major health challenge affecting pregnancy outcome worldwide. The objectives of this study were to investigate the impact of severe-moderate anaemia in the first trimester, as well as changes in haemoglobin during pregnancy among non-anaemic women, on foetal weight, placental blood flow and newborn anthropometrics. METHODS: In a prospective cohort study, 346 women residing in rural Tanzania were followed throughout pregnancy with serial ultrasound and newborn anthropometrics assessed within 24 h of delivery. Associations between placental blood flow, foetal weight and newborn anthropometrics with either first trimester severe-moderate anaemia (haemoglobin≤9.5 g/dL) or changes in haemoglobin from the first to the third trimester among non-anaemic women, were assessed by mixed model regression and multiple linear regression, adjusting for maternal and foetal co-variables. Foetal weights and birthweight were converted to z-scores using a population based sex-specific weight reference. RESULTS: Severe-moderate anaemia in the first trimester was associated with significantly reduced foetal weight z-scores (adjusted mean difference (aMD) -0.44 (95% CI -0.81, -0.07)) and newborn anthropometric indices (birth weight z-score aMD -0.55 (-0.9, -0.13), abdominal circumference aMD -11 mm (95% CI -20, -3)). There were no association between first trimester severe-moderate anaemia and placental blood flow. Among women who were non-anaemic in the first trimester, women with the least reduction in haemoglobin (Δ ≥ -0.3 g/dL) delivered significantly smaller newborns (birthweight z-score aMD -0.55 (-0.91, -0.20), abdominal circumference aMD -10 mm (95% CI -17, -3), compared to women with the greatest reduction (Δ haemoglobin ≤ -1.4 g/dL)). CONCLUSIONS: Severe-moderate anaemia in early pregnancy was associated with smaller newborn anthropometrics which was reflected in smaller mean foetal weights in the second and third trimester. Furthermore, among women who were non-anaemic in the first trimester, there was an association between smaller newborn anthropometrics and limited haemoglobin decrease during pregnancy, possibly reflecting insufficient plasma expansion.
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Anemia , Complicações Hematológicas na Gravidez , Gravidez , Feminino , Recém-Nascido , Humanos , Primeiro Trimestre da Gravidez , Peso Fetal , Peso ao Nascer , Estudos Prospectivos , Tanzânia/epidemiologia , Complicações Hematológicas na Gravidez/epidemiologia , Placenta , Anemia/epidemiologia , Resultado da Gravidez/epidemiologia , Hemoglobinas , Estudos de CoortesRESUMO
PURPOSE OF REVIEW: In this review, we explore the investigational applications of optical coherence tomography (OCT) in retinopathy of prematurity (ROP), the insights they have delivered thus far, and key milestones for its integration into the standard of care. RECENT FINDINGS: While OCT has been widely integrated into clinical management of common retinal diseases, its use in pediatric contexts has been undermined by limitations in ergonomics, image acquisition time, and field of view. Recently, investigational handheld OCT devices have been reported with advancements including ultra-widefield view, noncontact use, and high-speed image capture permitting real-time en face visualization. These developments are compelling for OCT as a more objective alternative with reduced neonatal stress compared to indirect ophthalmoscopy and/or fundus photography as a means of classifying and monitoring ROP. SUMMARY: OCT may become a viable modality in management of ROP. Ongoing innovation surrounding handheld devices should aim to optimize patient comfort and image resolution in the retinal periphery. Future clinical investigations may seek to objectively characterize features of peripheral stage and explore novel biomarkers of disease activity.
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Retinopatia da Prematuridade , Recém-Nascido , Humanos , Criança , Retinopatia da Prematuridade/diagnóstico , Tomografia de Coerência Óptica/métodos , Retina , Oftalmoscopia/métodos , Técnicas de Diagnóstico OftalmológicoRESUMO
Nanotechnology has transformed drug delivery, offering opportunities to enhance treatment outcomes while minimizing adverse effects. This study focuses on gelatin-coated cobalt and manganese ferrite nanoparticles for potential drug delivery applications. The synthesis involved a co-precipitation method, and the nanoparticles were characterized using various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, and vibrating sample magnetometer (VSM). Results revealed stable structures, distinct chemical features introduced by gelatin coating, and unique magnetic properties. The hemolysis assay demonstrated reduced hemolytic activity with gelatin coating, enhancing biocompatibility. Drug release studies indicated differential release profiles, with gelatin-coated cobalt ferrite exhibiting higher drug release compared to gelatin-coated manganese ferrite. The Higuchi model supported diffusion-controlled drug release for gelatin-coated cobalt ferrite. These findings suggest the potential of gelatin-coated ferrite nanoparticles for controlled and targeted drug delivery, highlighting their significance in advancing nanomedicine.
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The (0.90)Y2O3:(0.10-x)Eu3+:(x)Bi3+ nanophosphors (0.00 ≤ x ≤ 0.06) are synthesised using chemical combustion citrate route and characterized via X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, UV- visible and photoluminescence spectroscopy. The scanning electron micrographs indicate that the grain size of the phosphors ranges between 40 to 50 nm. The photoluminescence (PL) spectra, acquired under the excitation wavelength of 365 nm of ultraviolet light, show emission peaks at wavelengths 580 nm, 586-598 nm, 610 nm, 629-661 nm and 686-695 nm corresponding to the 5D0 â 7FJ electronic transitions of the Eu3+ ion with J = 0, 1, 2, 3 and 4, respectively. The most intense PL spectra at 611 nm (5D0 â 7F2), showcasing reddish-orange emission, indicate a higher concentration of Eu3+ ions in asymmetric sites within the Y2O3 host matrix. The presence of the distinct electronic transitions of Eu3+ in PL spectra acclaims that Bi3+ ions transfer their energy efficiently to Eu3+ ions in the matrix. Physical and chemical tests are being conducted on nanophosphors with Bi3+ substitutional doping of x = 0.02 and x = 0.04, both demonstrating intense PL emission. Magnetisation measurements suggest the soft magnetic nature of the nanophosphors, attributing it to the presence of Eu3+ ions in the 7F2 state. The highest PL intensity is seen in the nanophosphor (x = 0.04) with substitutional doping of 6% of Eu3+ and 4% of Bi3+ in Y2O3. This nanophosphor also demonstrates excellent optical stability in the investigated conditions and exhibits soft magnetic behaviour, positioning it as a promising material for incorporation as a fluorescent magnetic pigment in security ink applications. These features serve to prevent counterfeiting of secured documents both optically and magnetically.
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PURPOSE: The objective of this meta-analysis is to compare available computer-assisted navigation platforms by key performance metrics including pedicle screw placement accuracy, operative time, neurological complications, and blood loss. METHODS: A systematic review was conducted using major databases for articles comparing pedicle screw accuracy of computer-assisted navigation to conventional (freehand or fluoroscopy) controls via post-operative computed tomography. Outcome data were extracted and pooled by random-effects model for analysis. RESULTS: All navigation platforms demonstrated significant reduction in risk of breach, with Stryker demonstrating the highest accuracy compared to controls (OR 0.16 95% CI 0.06 to 0.41, P < 0.00001, I2 = 0%) followed by Medtronic. There were no significant differences in accuracy or most surgical outcome measures between platforms; however, BrainLab demonstrated significantly faster operative time compared to Medtronic by 30 min (95% CI - 63.27 to - 2.47, P = 0.03, I2 = 74%). Together, there was significantly lower risk of major breach in the navigation group compared to controls (OR 0.42, 95% CI 0.27-0.63, P < 0.0001, I2 = 56%). CONCLUSIONS: When comparing between platforms, Stryker demonstrated the highest accuracy, and Brainlab the shortest operative time, both followed by Medtronic. No significant difference was found between platforms regarding neurologic complications or blood loss. Overall, our results demonstrated a 60% reduction in risk of major breach utilizing computer-assisted navigation, coinciding with previous studies, and supporting its validity. This study is the first to directly compare available navigation platforms offering insight for further investigation and aiding in the institutional procurement of platforms. LEVEL 3 EVIDENCE: Meta-analysis of Level 3 studies.
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Parafusos Pediculares , Fusão Vertebral , Cirurgia Assistida por Computador , Humanos , Benchmarking , Cirurgia Assistida por Computador/métodos , Coluna Vertebral/cirurgia , Tomografia Computadorizada por Raios X/métodos , Fluoroscopia/métodos , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodosRESUMO
Spermatozoa from high-fertile (HF) and low-fertile (LF) breeding bulls were subjected to high-throughput next-generation sequencing to identify important Single nucleotide polymorphisms (SNPs) and novel variants associated with fertility. A total of 77,038 genome-wide SNPs were identified, among which, 10,788 were novel variants. A total of 42,290 and 34,748 variants were recorded with 6115 and 4673 novel variants in in HF and LF bulls, respectively. Higher number of SNPs were identified in HF compared to LF bulls. GO analysis of filtered genes with significant variations in HF bulls indicated their involvement in oxidative phosphorylation and metabolic pathways. GO analysis of filtered genes with significant variation in LF bulls revealed their involvement in Ca2++ ion binding, structural constituent of ribosome, and biological processes like translation and ribosomal small subunit assembly. The study identified SNPs in candidate genes including TPT1, BOLA-DRA, CD74, RPS17, RPS28, RPS29, RPL14, RPL13, and RPS27A, which are linked to sperm functionality, survival, oxidative stress, and bull fertility. The identified SNPs could be used in selection of bulls for high fertility and the variation in these genes could be established as an explanation for the fertility differences in bulls upon validation in large number of bulls.
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Polimorfismo de Nucleotídeo Único , Sêmen , Bovinos/genética , Masculino , Animais , Polimorfismo de Nucleotídeo Único/genética , Espermatozoides/metabolismo , Fertilidade/genéticaRESUMO
BACKGROUND: We characterized subsidence of an uncemented single-taper femoral stem in primary total hip arthroplasty (THA), determined factors associated with subsidence, and evaluated the impact of subsidence on outcome. METHODS: This retrospective study included 502 primary THAs performed using a single-taper stem in Dorr type-A and type-B femora between 2014 and 2018. Subsidence was measured based on distance from the greater trochanter to stem shoulder on calibrated X-rays. Demographics, case-specific data, and outcomes were collected. Changes in subsidence and variables associated with subsidence were determined. RESULTS: Stem subsidence was 1.5 ± 2.3 mm, 1.6 ± 2.0 mm, 2.0 ± 2.6 mm, 2.3 ± 2.3 mm, 2.6 ± 2.5 mm, and 2.7 ± 3.0 mm at 6 weeks, 3 months, 6 months, 1 year, 2 years, and ≥3 years from THA, respectively. Subsidence across all patients at final mean follow-up of 24 months (range, 1 to 101 months) was 2.2 ± 2.6 mm. Pairwise comparison demonstrated that subsidence occurred predominantly within the first 6 months. Significant subsidence (≥5 mm) occurred in 17.3% and was associated with a body mass index (BMI) ≥25 (P = .04). Dorr type, age, sex, and American Society of Anesthesiologists class were not associated with subsidence. There were 2 patients (0.4%) who underwent a revision that could be attributed to subsidence. There was no association between subsidence and pain, limp, need for ambulatory aid, or analgesic use. CONCLUSION: In primary THAs performed using a single-taper prosthesis, average subsidence was 2.2 mm and significant subsidence occurred in 17.3%. Patient BMI was associated with subsidence. Revision surgery related to subsidence was infrequent (0.4%).
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Artroplastia de Quadril , Prótese de Quadril , Humanos , Estudos Retrospectivos , Desenho de Prótese , Fêmur/cirurgia , ReoperaçãoRESUMO
Native potato clones grown in Peru contain bioactive compounds beneficial to human health. This study aimed to optimize the spray-drying nanoencapsulation of native potato phenolic extracts utilizing a central composite design and response surface methodology, obtaining the optimal treatment to an inlet temperature of 120 °C and an airflow of 141 L/h in the nano spray dryer B-90, which allowed maximizing the yield of encapsulation, antioxidant capacity (DPPH), encapsulation efficiency (EE), total phenolic compounds, and total flavonoids; on the other hand, it allowed minimizing hygroscopicity, water activity (Aw), and moisture. Instrumental characterization of the nanocapsules was also carried out, observing a gain in lightness, reddening of the color, and spherical nanoparticles of heterogeneous size (133.09-165.13 nm) with a negative ζ potential. Thermal, infrared, and morphological analyses confirmed the encapsulation of the core in the wall materials. Furthermore, an in vitro release study of phenolic compounds in an aqueous solution achieved a maximum value of 9.86 mg GAE/g after 12 h. Finally, the obtained nanocapsules could be used in the food and pharmaceutical industry.
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Nanocápsulas , Nanopartículas , Solanum tuberosum , Humanos , Secagem por Atomização , Antioxidantes/química , Nanopartículas/química , Água/químicaRESUMO
Prickly pear fruits are seasonal and have shades ranging from pale green to deep purple. Their pigments are associated with bioactive compounds, being sensitive to thermal transformation processes for their conservation. The objective of this research was to evaluate the bioactive compounds and the sensory analysis of freeze-dried prickly pear fruits from an inter-Andean valley in Peru. The prickly pear fruits of the morada, anaranjada, and blanca ecotypes came from an inter-Andean valley in Peru at 2972 m altitude. The sliced fruits were freeze-dried at -40 °C and 0.25 mTorr, and the total polyphenol content (TPC), vitamin C, and antioxidant activity (AA) were determined, as well as the color L* a* b*, color index (CI*), FTIR spectra, and mineral content. In the same way, sensory analysis of preferences with nine scales was applied. It was observed that in the freeze-dried fruits, TPC, AA, and vitamin C increased significantly (p-value < 0.05), and their corresponding functional groups increased in intensity in their corresponding FTIR spectra; furthermore, trace elements such as Cu, Fe, Se, Zn, Si, and Mn were identified. On the other hand, freeze-drying provided deeper colors to the fruits, which most panelists said they "very much liked" during the sensory analysis, although the texture was not very well accepted, with most panelists reporting being "indifferent" towards it. The freeze-drying technique allows the bioactive and sensory attributes of prickly pear fruits from inter-Andean valleys to be preserved, making it a potential fruit for export and conservation due to its seasonality.
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Antioxidantes , Frutas , Frutas/química , Peru , Ácido Ascórbico , Polifenóis/análise , VitaminasRESUMO
AIMS: A clinical study to compare the horizontal condylar guidance using protrusive interocclusal records, orthopantomography (OPG), and cone-beam computed tomography (CBCT) in edentulous patients. SUBJECTS AND METHODS: Thirty-six edentulous subjects were selected as per predetermined criteria. Horizontal condylar guidance was recorded using protrusive interocclusal records (PIR), OPG, and CBCT for each patient. The PIR were obtained using extraoral Gothic arch tracers to program the Hanau articulator. The horizontal condylar guidance angles (HCGAs) were digitally constructed using appropriate software along the posterior slope of articular eminence for all radiographs. The collected data were recorded, tabulated, and statistically analyzed. RESULTS: The condylar guidance angle values were tested for significance to compare the different angles. The correlation of HCGA measurements on both sides between the three groups was analyzed. The PIR and OPG methods (p = 0.001), as well as the OPG and CBCT methods (p = 0.001), show substantial differences on both sides. On the contrary, the PIR and CBCT methods did not differ significantly (p = 0.11). CONCLUSION: Cone-beam computed tomography is as reliable and accurate as the clinical method. A significant correlation exists between the clinical method and CBCT. It can be used as a dependable adjunct to the clinical method of HCGA measurement. CLINICAL SIGNIFICANCE: Cone-beam computed tomography can overcome the shortcomings of the conventional clinical methods to determine the accurate horizontal condylar guidance angulation measurement. It is safer with minimum discomfort and wastage of time for the patients.
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Boca Edêntula , Tomografia Computadorizada de Feixe Cônico Espiral , Humanos , Radiografia Panorâmica , Registro da Relação Maxilomandibular/métodos , Côndilo Mandibular/diagnóstico por imagem , Boca Edêntula/diagnóstico por imagem , Tomografia Computadorizada de Feixe CônicoRESUMO
AIMS: Meningiomas are the most frequent primary brain tumours. Recently, knowledge about the molecular drivers underlying aggressive meningiomas has been expanded. A hotspot mutation in the AKT1 gene (AKT1E17K ), which is found in meningiomas at the convexity and especially at the skull base, has been associated with earlier tumour recurrence. METHODS: Here, we analysed the effects of the AKT1E17K mutation and treatment response to the Akt inhibitor AZD5363 in transgenic meningioma cell clones and mouse xenografts modelling convexity or skull base meningiomas. RESULTS: We show that the AKTE17K mutation significantly enhances meningioma cell proliferation and colony size in vitro, resulting in significantly shortened survival times of mice carrying convexity or skull base AKT1E17K xenografts. Treatment of mutant cells or xenografts (150 mg/kg/d) with AZD5363 revealed a significant decrease in cell proliferation and colony size and a prolongation of mouse survival. Western blots revealed activation of AKT1 kinase (phosphorylation at Ser273 and Thr308) by the E17K mutation in human meningioma samples and in our in vitro and in vivo models. CONCLUSIONS: Our data suggest that AKT1E17K mutated meningiomas are a promising selective target for AZD5363.
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Proliferação de Células/efeitos dos fármacos , Neoplasias Meníngeas/genética , Meningioma/genética , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Neoplasias da Base do Crânio/genética , Animais , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Humanos , Neoplasias Meníngeas/patologia , Meningioma/patologia , Camundongos , Proteínas Proto-Oncogênicas c-akt/genética , Pirimidinas/farmacologia , Pirróis/farmacologia , Neoplasias da Base do Crânio/patologiaRESUMO
Machine-readable chemical structure representations are foundational in all attempts to harness machine learning for the prediction of reactivities, selectivities, and chemical properties directly from molecular structure. The featurization of discrete chemical structures into a continuous vector space is a critical phase undertaken before model selection, and the development of new ways to quantitatively encode molecules is an active area of research. In this Account, we highlight the application and suitability of different representations, from expert-guided "engineered" descriptors to automatically "learned" features, in different prediction tasks relevant to organic and organometallic chemistry, where differing amounts of training data are available. These tasks include statistical models of stereo- and enantioselectivity, thermochemistry, and kinetics developed using experimental and quantum chemical data.The use of expert-guided molecular descriptors provides an opportunity to incorporate chemical knowledge, domain expertise, and physical constraints into statistical modeling. In applications to stereoselective organic and organometallic catalysis, where data sets may be relatively small and 3D-geometries and conformations play an important role, mechanistically informed features can be used successfully to obtain predictive statistical models that are also chemically interpretable. We provide an overview of several recent applications of this approach to obtain quantitative models for reactivity and selectivity, where topological descriptors, quantum mechanical calculations of electronic and steric properties, along with conformational ensembles, all feature as essential ingredients of the molecular representations used.Alternatively, more flexible, general-purpose molecular representations such as attributed molecular graphs can be used with machine learning approaches to learn the complex relationship between a structure and prediction target. This approach has the potential to out-perform more traditional representation methods such as "hand-crafted" molecular descriptors, particularly as data set sizes grow. One area where this is particularly relevant is in the use of large sets of quantum mechanical data to train quantitative structure-property relationships. A general approach toward curating useful data sets and training highly accurate graph neural network models is discussed in the context of organic bond dissociation enthalpies, where this strategy outperforms regression using precomputed descriptors.Finally, we describe how graph neural network predictions can be incorporated into mechanistically informed statistical models of chemical reactivity and selectivity. Once trained, this approach avoids the expensive computational overhead associated with quantum mechanical calculations, while maintaining chemical interpretability. We illustrate examples for which fast predictions of bond dissociation enthalpy and of the identities of radicals formed through cleavage of a molecule's weakest bond are used in simple physical models of site-selectivity and reactivity.
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Lignocellulosic biomass offers a renewable carbon source which can be anaerobically digested to produce short-chain carboxylic acids. Here, we assess fuel properties of oxygenates accessible from catalytic upgrading of these acids a priori for their potential to serve as diesel bioblendstocks. Ethers derived from C2 and C4 carboxylic acids are identified as advantaged fuel candidates with significantly improved ignition quality (>56% cetane number increase) and reduced sooting (>86% yield sooting index reduction) when compared to commercial petrodiesel. The prescreening process informed conversion pathway selection toward a C11 branched ether, 4-butoxyheptane, which showed promise for fuel performance and health- and safety-related attributes. A continuous, solvent-free production process was then developed using metal oxide acidic catalysts to provide improved thermal stability, water tolerance, and yields. Liter-scale production of 4-butoxyheptane enabled fuel property testing to confirm predicted fuel properties, while incorporation into petrodiesel at 20 vol % demonstrated 10% improvement in ignition quality and 20% reduction in intrinsic sooting tendency. Storage stability of the pure bioblendstock and 20 vol % blend was confirmed with a common fuel antioxidant, as was compatibility with elastomeric components within existing engine and fueling infrastructure. Technoeconomic analysis of the conversion process identified major cost drivers to guide further research and development. Life-cycle analysis determined the potential to reduce greenhouse gas emissions by 50 to 271% relative to petrodiesel, depending on treatment of coproducts.
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The reason for poor semen quality among the breeding bulls is not well understood. In the present study, we performed high-throughput RNAseq analysis of spermatozoa to identify the SNPs present in good and poor-quality semen-producing Holstein Friesian breeding bulls. A total of 21,360 and 44,650 SNPs were identified in good and poor-quality semen with a minimum read depth of 20, among which 4780 and 8710 novel variants were observed in good and poor-quality semen, respectively. Greater SNPs and indels variations were observed in poor compared to good-quality semen. In poor-quality semen, SNP variations were observed in ZNF280B, SLC26A2, DMXL1, OR52A1, MACROD2 and REV1 genes, which are associated with regulation of spermatogenesis, post-testicular maturation, Cl- channel activity, V-ATPase-mediated intracellular vesicle acidification, a mono-ADP-ribosyl hydrolase and ATR-Chk1 checkpoint activation. GO analysis of filtered genes with significant variations between good and poor-quality semen showed enrichment in important pathways related to semen quality such as MAPK signalling pathway, Akt signalling pathway, focal adhesion, cAMP signalling pathway, and Rap1 signalling pathway. Network analysis of filtered genes in poor-quality semen showed variations in pathways of purine metabolism, pyrimidine metabolism, prolactin signalling pathway and RNA cap-binding complex. It is inferred that SNP in genes involved in maintaining sperm functions could be the reason for poor-quality semen production in bulls, and the identified SNPs hold potential to be used as biomarkers for semen quality in bulls.
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Polimorfismo de Nucleotídeo Único , Análise do Sêmen , Adenosina Trifosfatases , Animais , Biomarcadores , Cruzamento , Bovinos/genética , Hidrolases , Masculino , Prolactina , Proteínas Proto-Oncogênicas c-akt , Purinas , Pirimidinas , Capuzes de RNA , Sêmen/fisiologia , Análise do Sêmen/veterinária , Motilidade dos Espermatozoides , EspermatozoidesRESUMO
Non-synonymous missense SNPs (nsSNPs) in CPE and GNAS genes were investigated computationally. In silico identified nsSNPs were experimentally validated in type II diabetes mellitus (T2DM) in Pakistani Pathan population using next generation sequencing (NGS). Sixty two high-risk nsSNPs in CPE and 44 in GNAS were identified. Only 12 in GNAS were clinically significant. Thirty six high-risk nsSNPs in CPE and 08 clinically significant nsSNPs in GNAS lies in the most conserved regions. I-mutant predicted that nsSNPs decrease the proteins stability and ModPred predicted 20 and 12 post-translational modification sites in CPE and GNAS proteins respectively. Ramachandran plot showed 88.7% residues are in the most favored region of protein models. By experimentation, none of the nsSNPs were found to be associated with T2DM. In conclusion, this study differentiates the deleterious nsSNPs from the neutral ones. Although nsSNPs are not associated with T2DM, they can be targeted in other CPE and GNAS genes related disorders.
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Diabetes Mellitus Tipo 2 , Polimorfismo de Nucleotídeo Único , Carboxipeptidase H , Cromograninas/genética , Diabetes Mellitus Tipo 2/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Modelos Moleculares , Estabilidade ProteicaRESUMO
At the local scale, environmental parameters often require monitoring by means of affordable measuring techniques and technologies given they need to be frequently surveyed. Streamflow in riverbeds or in channels is a hydrological variable that needs to be monitored in order to keep the runoff regimes under control and somehow forecast floods, allowing prevention of damage for people and infrastructure. Moreover, measuring such a variable is always extremely important for the knowledge of the environmental status of connected aquatic ecosystems. This paper presents a new approach to assessing hydrodynamic features related to a given channel by means of a beamforming technique that was applied to video sensing. Different features have been estimated, namely the flow velocity, the temperature, and the riverbed movements. The applied beamforming technique works on a modified sum and delay method, also using the Multiple Signal Classification algorithm (MUSIC), by acting as Synthetic Aperture Radar (SAR) post-processing. The results are very interesting, especially compared to the on-site measured data and encourage the use of affordable video sensors located along the channel or river course for monitoring purposes. The paper also illustrates the use of beamforming measurements to be calibrated by means of conventional techniques with more accurate data. Certainly, the results can be improved; however, they indicate some margins of improvements and updates. As metrics of assessment, a histogram of greyscale/pixels was adopted, taking into account the example of layers and curve plots. They show changes according to the locations where the supporting videos were obtained.
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Ecossistema , Radar , Algoritmos , Inundações , Humanos , RiosRESUMO
INTRODUCTION: Voluntary medical male circumcision (VMMC), an effective HIV prevention programme for men, is implemented in East and Southern Africa. Approximately 50% of VMMC clients are aged below 15 years. More targeted interventions to reach older men and others at higher short-term HIV risk are needed. METHODS: We implemented a quality improvement project testing the effectiveness of an active referral-based VMMC recruitment approach, targeting men attending STI clinics and those escorting partners to antenatal care (ANC) clinics, at Bwaila Hospital in Lilongwe, Malawi. We compared the proportions aged older than 15 years among men who received VMMC following referral from STI and ANC clinics with those among men referred from standard community mobilisation. We also analysed referral cascades to VMMC. RESULTS: In total, 330 clients were circumcised after referral from STI (242) and ANC (88) clinics, as compared with 3839 other clients attributed to standard community mobilisation. All clients from ANC and STI clinics were aged over 15 years, as compared with 69% from standard community mobilisation. STI clinics had a higher conversion rate from counselling to VMMC than ANC (12% vs 9%) and a higher contribution to total circumcisions performed at the VMMC clinic (6% vs 2%). CONCLUSIONS: Integrating VMMC recruitment and follow-up in STI and ANC clinics co-located with VMMC services can augment demand creation and targeting of men at risk of HIV, based on age and STI history. This approach can be replicated at least in similar health facilities with ANC and STI services in close proximity to VMMC service delivery.