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Camelid single-domain antibodies, also known as nanobodies, can be readily isolated from naïve libraries for specific targets but often bind too weakly to their targets to be immediately useful. Laboratory-based genetic engineering methods to enhance their affinity, termed maturation, can deliver useful reagents for different areas of biology and potentially medicine. Using the receptor binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein and a naïve library, we generated closely related nanobodies with micromolar to nanomolar binding affinities. By analyzing the structure-activity relationship using X-ray crystallography, cryoelectron microscopy, and biophysical methods, we observed that higher conformational entropy losses in the formation of the spike protein-nanobody complex are associated with tighter binding. To investigate this, we generated structural ensembles of the different complexes from electron microscopy maps and correlated the conformational fluctuations with binding affinity. This insight guided the engineering of a nanobody with improved affinity for the spike protein.
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Anticorpos Neutralizantes , Anticorpos Antivirais , Afinidade de Anticorpos , SARS-CoV-2 , Anticorpos de Domínio Único , Glicoproteína da Espícula de Coronavírus , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/genética , Anticorpos Antivirais/química , Anticorpos Antivirais/genética , Afinidade de Anticorpos/genética , Microscopia Crioeletrônica , Entropia , Engenharia Genética , Humanos , Ligação Proteica , Domínios Proteicos , SARS-CoV-2/imunologia , Anticorpos de Domínio Único/química , Anticorpos de Domínio Único/genética , Glicoproteína da Espícula de Coronavírus/imunologiaRESUMO
Pharmacokinetic models rarely undergo external validation in vulnerable populations such as critically ill infants, thereby limiting the accuracy, efficacy, and safety of model-informed dosing in real-world settings. Here, we describe an opportunistic approach using dried blood spots (DBS) to evaluate a population pharmacokinetic model of metronidazole in critically ill preterm infants of gestational age (GA) ≤31 weeks from the Metronidazole Pharmacokinetics in Premature Infants (PTN_METRO, NCT01222585) study. First, we used linear correlation to compare 42 paired DBS and plasma metronidazole concentrations from 21 preterm infants [mean (SD): post natal age 28.0 (21.7) days, GA 26.3 (2.4) weeks]. Using the resulting predictive equation, we estimated plasma metronidazole concentrations (ePlasma) from 399 DBS collected from 122 preterm and term infants [mean (SD): post natal age 16.7 (15.8) days, GA 31.4 (5.1) weeks] from the Antibiotic Safety in Infants with Complicated Intra-Abdominal Infections (SCAMP, NCT01994993) trial. When evaluating the PTN_METRO model using ePlasma from the SCAMP trial, we found that the model generally predicted ePlasma well in preterm infants with GA ≤31 weeks. When including ePlasma from term and preterm infants with GA >31 weeks, the model was optimized using a sigmoidal Emax maturation function of postmenstrual age on clearance and estimated the exponent of weight on volume of distribution. The optimized model supports existing dosing guidelines and adds new data to support a 6-hour dosing interval for infants with postmenstrual age >40 weeks. Using an opportunistic DBS to externally validate and optimize a metronidazole population pharmacokinetic model was feasible and useful in this vulnerable population.
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Recém-Nascido Prematuro , Metronidazol , Humanos , Lactente , Recém-Nascido , Antibacterianos/farmacocinética , Estado Terminal , Idade Gestacional , Metronidazol/farmacocinéticaRESUMO
OBJECTIVE: Breast milk (BM) enhancement is often used to meet the nutritional needs of preterm infants after hospital discharge to achieve optimal growth. This study compared growth at 18-28 months corrected age (CA) among very preterm (VP) and very low birth weight (VLBW) infants discharged from the neonatal intensive care units (NICUs) on two BM enhancements. METHODS: We conducted a retrospective chart review study of infants born between January 1, 2013 and December 31, 2017, with gestational age < 32 weeks or birthweight < 1500 g, discharged from the NICU on BM enhancements; fortification of BM with infant formula additives (BM-F) or unfortified BM supplemented with bottle feeds of infant formula (BM-S). BM enhancements were nonrandomized and determined by the medical team. A linear mixed model regression analysis with propensity score matching was used to estimate the adjusted associations between the nutrition plan at discharge and growth outcomes at 18-28 months CA follow-up. RESULTS: Two hundred and fifty-one VLBW/VP infants were included. Compared with BM-S, infants discharged on BM-F were more likely to continue receiving BM at 8-12 months CA, and had lower head circumference, weight-for-length z scores, and higher incidence of moderate malnutrition (p ≤ 0.01). After adjusting for confounders, discharge on BM-F was associated with a lower incidence of overweight/obesity at 18-28 months CA (odds interval: 0.45; confidence interval: 0.21-0.96; p = 0.04). CONCLUSIONS: This retrospective study suggests that VLBW/VP infants discharged on BM-F received BM longer, had lower growth parameter and were less likely to be overweight/obese at 18-28 months CA. Further studies are needed to evaluate the role of postdischarge nutrition on preterm born children's growth, metabolic disease, and neurodevelopmental outcomes.
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Homogeneous and nanometric metal clusters with unique electronic structures are promising for catalysis, however, common synthesis techniques for metal clusters suffer from large size and even metal nanocrystals attributing to their high surface energy and unsaturated configurations. Herein, a generalized rapid annealing strategy for synthesizing a series of supported metal clusters as superior catalysts is developed. Remarkably, TiO2 supported platinum nanoclusters (Pt NC/TiO2 ) exhibits the excellent catalytic activity to realize phenol hydrogenation under mild conditions. The complete phenol conversion rate and 100% selectivity toward KA oil are achieved in aqueous solution at room temperature and normal pressure. Semi-continuous scale up production of KA oil is successfully performed under mild conditions. Such excellent performance mainly originates from the partial reconstruction of Pt NC/TiO2 in aqueous phenol solution. Considering that the phenol can be produced from lignin, this study underpins a facile, sustainable, and economical route to synthesize nylon from biomass.
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Amylases are biologically active enzymes that can hydrolyze starch to produce dextrin, glucose, maltose, and oligosaccharides. The amylases contribute approximately 30% to the global industrial enzyme market. The globally produced amylases are widely used in textile, biofuel, starch processing, food, bioremediation of environmental pollutants, pulp, and paper, clinical, and fermentation industries. The purpose of this review article is to summarize recent trends and aspects of α-amylases, classification, microbial production sources, biosynthesis and production methods, and its broad-spectrum applications for industrial purposes, which will depict the latest trends in α-amylases production. In the present article, we have comprehensively compared the biodiversity of α-amylases in different model organisms ranging from archaea to eukaryotes using in silico structural analysis tools. The detailed comparative analysis: regarding their structure, function, cofactor, signal peptide, and catalytic domain along with their catalytic residues of α-amylases in 16 model organisms were discussed in this paper. The comparative studies on alpha (α) amylases' secondary and tertiary structures, multiple sequence alignment, transmembrane helices, physiochemical properties, and their phylogenetic analysis in model organisms were briefly studied. This review has documented the recent trends and future perspectives of industrially important novel thermophilic α-amylases. In conclusion, this review sheds light on the current understanding and prospects of α-amylase research, highlighting its importance as a versatile enzyme with numerous applications and emphasizing the need for further exploration and innovation in this field.
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Amilases , alfa-Amilases , alfa-Amilases/química , alfa-Amilases/genética , Filogenia , Amilases/genética , Catálise , AmidoRESUMO
OBJECTIVE: This study aimed to estimate national time trends of overall and statewise antibiotic utilization (AU) rates for suspected neonatal sepsis (SNS) in the United States. STUDY DESIGN: In this cross-sectional study, we used retrospective linked birth cohort and vital records data from the Centers for Disease Control and Prevention Wide-ranging ONline Data for Epidemiologic Research database for the years 2016 to 2020 and analyzed data containing antibiotic use for SNS. The primary outcome was proportional national and state-specific AU rates per 1,000 live births during the birth hospitalization. Secondary outcomes included overall trends and association between maternal education, race, sex, chorioamnionitis, mode of delivery, gestational age at birth, Apgar's scores, and insurance status with antibiotics exposure for SNS among newborns. Contingency tables, two-tailed t-test, and chi-square for independence tests were performed with statistical significance set at p < 0.05. RESULTS: For a birth cohort of >18 million, 2.2% of infants received antibiotics during birth hospitalization nationwide. There were wide variations in AU among U.S. states and territories, whereas overall treatment rates decreased by 16.1% (95% confidence interval [CI]: 15.2-17.0; p < 0.001). Compared with White newborns, Black newborns had higher AU rates (odds ratio [OR]: 1.33; 95% CI: 1.32-1.34), and Asians had the lowest rates (OR: 0.96; 95% CI: 0.95-0.97). There was a significant difference in mean AU rates by race (p < 0.001). Chorioamnionitis at birth significantly increased the odds for AU (OR: 14.5 ;95% CI: 14.4-14.6), although AU rates for chorioamnionitis showed a significant downward trend (OR: 0.52; 95% CI: 0.50-0.53) during the study period. CONCLUSION: Our findings suggest that there has been a gradual decline in AU for SNS in more than a third of states in last 5 years. While risk-based management approaches achieve widespread implementation, state- and nationwide quality improvement collaborates might have contributed to the relative decline in antibiotic use in newborns. Further studies are warranted to understand factors related to practice variation in the management of SNS in the United States KEY POINTS: · Early and prolonged use of antibiotics can lead to altered gut microbiome and adverse long-term neonatal outcomes.. · There is considerable clinical practice variation in antibiotic-prescribing practices for suspected neonatal sepsis.. · This cross-sectional study reports the differences in neonatal antibiotic usage patterns by region and maternal factors.. · Antibiotic use should be limited to newborns at high risk of infection and proven sepsis.. · Judicious use of antibiotics can be promoted by following evidence-based approaches to sepsis risk assessment..
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The ongoing coronavirus (COVID-19) pandemic requires enormous production of facemasks and related personal protection materials, thereby increasing the amount of nondegradable plastic waste. The core material for facemasks is melt-blown polypropylene (PP) fiber. Each disposable facemask consumes â¼0.7 g of PP fibers, resulting in annual global consumption and disposal of more than 1â¯150â¯000 tons of PP fibers annually. Herein, we developed a laser-assisted melt-blown (LAMB) technique to manufacture PP nanofibers with a quality factor of 0.17 Pa-1 and significantly reduced the filter's weight. We demonstrated that a standard surgical facemask could be made with only 0.13 g of PP nanofibers, saving approximately 80% of the PP materials used in commercial facemasks. Theoretical analysis and modeling were also conducted to understand the LAMB process. Importantly, nanofibers can be easily scaled up for mass production by upgrading traditional melt blown line with scanning laser-assisted melt-blown (SLAMB).
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COVID-19 , Nanofibras , COVID-19/prevenção & controle , Humanos , Lasers , Máscaras , PolipropilenosRESUMO
Photoluminescence (PL) in state-of-the-art 2D materials suffers from narrow spectral coverage, relatively broad linewidths, and poor room-temperature (RT) functionality. The authors report ultra-narrow linewidth photo-emitters (ULPs) across the visible to near-infrared wavelength at RT in polymorphic selenium nanoflakes (SeNFs), synthesized via a hot-pressing strategy. Photo-emitters in NIR exhibit full width at half maximum (Γ) of 330 ± 90 µeV, an order of magnitude narrower than the reported ULPs in 2D materials at 300 K, and decrease to 82 ± 70 µeV at 100 K, with coherence time (τc ) of 21.3 ps. The capping substrate enforced spatial confinement during thermal expansion at 250 °C is believed to trigger a localized crystal symmetry breaking in SeNFs, causing a polymorphic transition from the semiconducting trigonal (t) to quasi-metallic orthorhombic (orth) phase. Fine structure splitting in orth-Se causes degeneracy in defect-associated bright excitons, resulting in ultra-sharp emission. Combined theoretical and experimental findings, an optimal biaxial compressive strain of -0.45% cm-1 in t-Se is uncovered, induced by the coefficient of thermal expansion mismatch at the selenium/sapphire interface, resulting in bandgap widening from 1.74 to 2.23 ± 0.1 eV. This report underpins the underlying correlation between crystal symmetry breaking induced polymorphism and RT ULPs in SeNFs, and their phase change characteristics.
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BACKGROUND: The aim of this study was to investigate the influence of early-life pain/stress and medical characteristics on neurobehavioral outcomes in preterm infants. METHODS: A prospective cohort study was conducted with 92 preterm infants (28-32 weeks gestational age [GA]). Early-life pain/stress was measured via the Neonatal Infant Stressor Scale (NISS) during the first 28 days of NICU hospitalization. Neurobehavioral outcomes were evaluated using the NICU Network Neurobehavioral Scale at 36-38 weeks post-menstrual age. Functional regression and machine learning models were performed to investigate the predictors of neurobehavioral outcomes. RESULTS: Infants experienced daily acute pain/stress (24.99 ± 7.13 frequencies) and chronic events (41.13 ± 17.81 h). Up to 12 days after birth, both higher acute and chronic NISS scores were associated with higher stress scores; and higher chronic NISS scores were also related to lower self-regulation and quality of movement. Younger GA predicted worse neurobehavioral outcomes; GA < 31.57 weeks predicted worse stress/abstinence, self-regulation, and excitability; GA < 30.57 weeks predicted poor quality of movement. A higher proportion of maternal breastmilk intake predicted better self-regulation, excitability, and quality of movement in older GA infants. CONCLUSIONS: Preterm infants are vulnerable to the impact of early-life pain/stress. Neurobehavioral outcomes are positively associated with increased GA and higher maternal breastmilk intake. IMPACT: During the first 12 days of life, preterm infant neurobehavioral outcomes were vulnerable to the negative impact of acute and chronic pain/stress. Future research is warranted to investigate the long-term effects of early-life pain/stress on neurobehavioral outcomes. Gestational age remains one of the critical factors to predict neurobehavioral outcomes in preterm infants; older gestational age significantly predicted better neurobehavioral outcomes. Feeding with a higher proportion of maternal breastmilk predicted better neurobehavioral outcomes. Future research is warranted to investigate how maternal breastmilk may buffer the negative effects of early-life pain/stress on neurobehavioral outcomes.
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Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal , Lactente , Humanos , Recém-Nascido , Idoso , Recém-Nascido Prematuro/fisiologia , Estudos Prospectivos , Hospitalização , DorRESUMO
BACKGROUND: Annually 2.5 million infants die in the first 28 days of life, with a significant regional distribution disparity. An estimated 80% of those could be saved if neonatal resuscitation were correctly and promptly initiated. A barrier to achieving the target is the knowledge and skills of healthcare workers. PURPOSE: The objective of this cluster randomized trial was to assess the improvement and retention of resuscitation skills of nurses, midwives, and birth attendants in 2 birth centers serving 60 villages in rural India using high-frequency, low-dose training. RESULTS: There was a significant difference ( P < .05) between the groups in the rate of resuscitation, with 18% needing resuscitation in the control group and 6% in the intervention group. The posttest scores for knowledge retention at the final 8-month evaluation were significantly better in the intervention group than in the control group (intervention group mean rank 19.4 vs control group mean rank 10.3; P < .05). The success rate of resuscitation was not significantly different among the groups. IMPLICATIONS FOR PRACTICE: Improved knowledge retention at 8 months and the lower need for resuscitation in the intervention group support the efficacy of the high-frequency, low-dose education model of teaching in this setting. IMPLICATIONS FOR RESEARCH: Replication of these findings in other settings with a larger population cohort is needed to study the impact of such intervention on birth outcomes in low-resource settings.
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Tocologia , Ressuscitação , Competência Clínica , Feminino , Pessoal de Saúde/educação , Humanos , Índia , Lactente , Recém-Nascido , Tocologia/educação , Gravidez , Ressuscitação/educaçãoRESUMO
Synthesis of silver (Ag) nanoparticles with controllable morphology and with high purity remains challenging. In this work, single crystalline Ag nanoparticles with uniform morphology and high purity are successfully synthesized based on the replacement reaction between aqueous Ag nitrate (AgNO3) and solid copper (Cu) via jet. We further demonstrate that the developed jet method is facile and morphology-controllable. It is believed that diffusion limited aggregation and oriented attachment mechanisms are responsible for the formation of Ag nanostructures. The synthesized nanoparticles were characterized by different techniques. Finally, the Ag nanoparticles are successfully applied to prepare the conductive ink for flexible electronics and wearable equipment. Furthermore, the conductivity, flexibility and stability of the conductive material are measured. The conductive pattern exhibits lowest resistivity of 6.7 µΩ cm, showing the good conductivity of the prepared conductive material. In addition, the prepared conductive material is flexible in nature and exhibits stability over a long period.
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OBJECTIVE: This study aimed to compare neurodevelopmental outcomes in preterm infants at 18 to 26 months corrected age (CA) who did versus did not achieve full oral feedings at 40 weeks postmenstrual age (PMA). STUDY DESIGN: This retrospective study included infants born between 2010 and 2015 with gestational age <32 weeks and followed between 18 and 26 months CA. Achievement of full oral feedings was defined as oral intake >130 mL/kg/d for >72 hours by 40 weeks PMA. Incidence of cognitive, language, or motor delay, or cerebral palsy at 18 to 26 months CA was compared in multivariable analyses for infants in the two feeding groups. RESULTS: Of 372 included infants, those achieving full oral feedings had lower incidence of any adverse neurodevelopmental outcome (p < 0.001) compared with those who did not achieve full oral feedings. In multivariable analyses, achievement of full oral feedings by 40 weeks PMA was associated with decreased odds of cognitive, language, and motor delays, cerebral palsy, and any adverse neurodevelopmental outcome at follow-up. CONCLUSION: Achievement of full oral feedings by 40 weeks PMA was associated with better adjusted neurodevelopmental outcomes at 18 to 26 months CA. Inability to fully feed orally at 40 weeks PMA may be a simple, clinically useful marker for risk of adverse neurodevelopmental outcomes.
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Deficiências do Desenvolvimento , Nutrição Enteral , Recém-Nascido Prematuro , Aleitamento Materno , Paralisia Cerebral , Feminino , Seguimentos , Gastrostomia , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Análise Multivariada , Estudos RetrospectivosRESUMO
In this exciting era of "next-gen cytogenetics," integrating genomic sequencing into the prenatal diagnostic setting is possible within an actionable time frame and can provide precise delineation of balanced chromosomal rearrangements at the nucleotide level. Given the increased risk of congenital abnormalities in newborns with de novo balanced chromosomal rearrangements, comprehensive interpretation of breakpoints could substantially improve prediction of phenotypic outcomes and support perinatal medical care. Herein, we present and evaluate sequencing results of balanced chromosomal rearrangements in ten prenatal subjects with respect to the location of regulatory chromatin domains (topologically associated domains [TADs]). The genomic material from all subjects was interpreted to be "normal" by microarray analyses, and their rearrangements would not have been detected by cell-free DNA (cfDNA) screening. The findings of our systematic approach correlate with phenotypes of both pregnancies with untoward outcomes (5/10) and with healthy newborns (3/10). Two pregnancies, one with a chromosomal aberration predicted to be of unknown clinical significance and another one predicted to be likely benign, were terminated prior to phenotype-genotype correlation (2/10). We demonstrate that the clinical interpretation of structural rearrangements should not be limited to interruption, deletion, or duplication of specific genes and should also incorporate regulatory domains of the human genome with critical ramifications for the control of gene expression. As detailed in this study, our molecular approach to both detecting and interpreting the breakpoints of structural rearrangements yields unparalleled information in comparison to other commonly used first-tier diagnostic methods, such as non-invasive cfDNA screening and microarray analysis, to provide improved genetic counseling for phenotypic outcome in the prenatal setting.
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Aberrações Cromossômicas , Anormalidades Congênitas/genética , Rearranjo Gênico , Nucleotídeos/genética , Diagnóstico Pré-Natal/métodos , Alelos , Mapeamento Cromossômico , Anormalidades Congênitas/diagnóstico , Feminino , Regulação da Expressão Gênica , Testes Genéticos , Genoma Humano , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Cariotipagem , Masculino , Gravidez , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Análise de Sequência de DNA , Translocação GenéticaRESUMO
A one-pot synthesis of bimetallic metal-organic frameworks (Co/Fe-MOFs) was achieved by treating stoichiometric amounts of Fe and Co salts with 2-aminoterephthalic acid (NH2 -BDC). Monometallic Fe (catalyst A) and Co (catalyst F) were also prepared along with mixed-metal Fe/Co catalysts (B-E) by changing the Fe/Co ratio. For mixed-metal catalysts (B-E) SEM energy-dispersive X-ray (EDX) analysis confirmed the incorporation of both Fe and Co in the catalysts. However, a spindle-shaped morphology, typically known for the Fe-MIL-88B structure and confirmed by PXRD analysis, was only observed for catalysts A-D. To test the catalytic potential of mixed-metal MOFs, reduction of nitroarenes was selected as a benchmark reaction. Incorporation of Co enhanced the activity of the catalysts compared with the parent NH2 -BDC-Fe catalyst. These MOFs were also tested as electrocatalysts for the oxygen evolution reaction (OER) and the best activity was exhibited by mixed-metal Fe/Co-MOF (Fe/Co batch ratio=1). The catalyst provided a current density of 10â mA cm-2 at 410â mV overpotential, which is comparable to the benchmark OER catalyst (i.e., RuO2 ). Moreover, it showed long-term stability in 1 m KOH. In a third catalytic test, dehydrogenation of sodium borohydride showed high activity (turnover frequency=87 min-1 ) and hydrogen generation rate (67â L min-1 g-1 catalyst). This is the first example of the synthesis of bimetallic MOFs as multifunctional catalysts particularly for catalytic reduction of nitroarenes and dehydrogenation reactions.
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Metallic dendrites with uniform morphology, high purity, and large yield remain challenging to synthesize. In this work, single-crystalline silver (Ag) dendrites with uniform morphology, high purity, and large yield are successfully synthesized by employing single replacement reaction between aqueous silver nitrate (AgNO3) and solid copper (Cu) by jet. The combined effect of diffusion-limited aggregation and the locally oriented attachment of Ag particles is responsible for the formation of silver dendrites under nonequilibrium conditions. Finally, the potential applications of as-synthesized silver dendrites are demonstrated by successfully preparing silver-based conductive ink for flexible electronics and wearable equipment. The conductive pattern exhibits resistivity of 7.2 µΩ·cm, showing good conductivity of the prepared conductive material. This facile and time-efficient synthetic route can be extended to synthesize other noble metal nanostructures with desired morphologies by adopting selective precursor salt concentrations and substrate metals with proper redox potentials.
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Multiple opioids are known to trigger mast cell degranulation. We report the case of a neonate with blistering skin lesions at birth who died of multi-organ failure after administration of morphine. Given the excessive histamine release and potential complications associated with morphine administration, alternative opioids and adjuvants should be considered in infants presenting with evidence of bullous or infiltrative skin lesions until mastocytosis is ruled out.
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Analgésicos Opioides/efeitos adversos , Mastocitose Cutânea/complicações , Mastocitose Cutânea/diagnóstico , Morfina/efeitos adversos , Insuficiência de Múltiplos Órgãos/etiologia , Evolução Fatal , Humanos , Recém-Nascido , MasculinoRESUMO
Water, considered as a universal solvent to dissolve salts, has been extensively studied as liquid electrolyte in electrochemical devices. The water/ice phase transition at around 0 °C presents a common phenomenon in nature, however, the chemical and electrochemical behaviors of ice have rarely been studied. Herein, we discovered that the ice phase provides efficient ionic transport channels and therefore can be applied as generalized solid-state ionic conductor. Solid state ionic conducting ices (ICIs) of Li+ , Na+ , Mg2+ , Al3+ , K+ , Mn2+ , Fe2+ , Co2+ , Ni2+ , Cu2+ , and Zn2+ , frozen from corresponding sulphate solutions, exhibit ionic conductivities ranging from ≈10-7 â S cm-1 (Zn2+ ) to ≈10-3 â S cm-1 (Li+ ) at temperatures spanning from -20 °C to -5 °C. The discovery of ICIs opens new insight to design and fabrication of solid-state electrolytes that are simple, inexpensive, and versatile.
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Aqueous solution syntheses are mostly based on mixing two solutions with different reactants. It is shown that freezing one solution and melting it in another solution provides a new interesting strategy to mix chemicals and to significantly change the reaction kinetics and thermodynamics. For example, a precursor solution containing a certain concentration of AgNO3 was frozen and dropped into a reductive NaBH4 solution at about 0 °C. The ultra-slow release of reactants was successfully achieved. An ice-melting process can be used to synthesize atomically dispersed metals, including cobalt, nickel, copper, rhodium, ruthenium, palladium, silver, osmium, iridium, platinum, and gold, which can be easily extended to other solution syntheses (such as precipitation, hydrolysis, and displacement reactions) and provide a generalized method to redesign the interphase reaction kinetics and ion diffusion in wet chemistry.
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To find the cure of world's one of the leading morbid and mortal disorders; diabetes mellitus and its most prevalent complication, 'diabetic-dyslipidemia', is one of the leading health challenges of 21st century. The use of phytomedicine is a glimmer of hope in this scenario. Studies of current decade have shown that methanolic extracts of Zingiber officinale and Curcuma longa have highly effective therapeutic potentials against the aforesaid disorders, however, which of the extracts has more potential is still unclear. Furthermore, synergistic effect of the extracts has never been studied. Forty-eight Albino adult rats of either sex were randomly divided into eight groups. A-D groups were containing healthy rats while E-H groups were of induced diabetic-dyslipidemic rats. For forty-two days, rats of each group were given either distilled water or Zingiber officinale methanolic extract (ZOME) or Curcuma longa methanolic extract (CLME) or ZOME+CLME therapies at dose rate of 300mg/100 mL dist. H2O/kg body wt/day. FPG and lipid profiles were estimated before and after the trial, and were statistically analyzed by one-way ANOVA along with Post-hoc Tukey's multiple comparison tests. Although, ZOME and CLME significantly (P<0.05) lowered fasting plasma glucose (FPG) levels and controlled lipid profiles in diabetic-dyslipidemic rats; yet, synergistic therapy of both extracts (ZOME+CLME) most significantly (P<0.05) controlled all parameters of diabetic-dyslipidemia (78.00±1.06mg/dL FPG, 62.00±0.58mg/dL TG, 66.50±0.76mg/dL cholesterol, 32.00±0.36mg/dL HDL, 22.43±0.64 mg/dL LDL, and 12.40±0.12mg/dL VLDL). Our findings may be useful to formulate new medicines having multiple potentials to control diabetes mellitus, dyslipidemia, and diabetic-dyslipidemia.
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Curcuma/química , Diabetes Mellitus Experimental/complicações , Dislipidemias/tratamento farmacológico , Extratos Vegetais/farmacologia , Zingiber officinale/química , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Sinergismo Farmacológico , Dislipidemias/etiologia , Feminino , Lipídeos/sangue , Masculino , Ratos WistarRESUMO
Despite substantial progress in the science and technology of 2D nanomaterials, facile fabrication of ultrathin 2D metals remains challenging. Herein, an efficient hot-pressing method is developed to fabricate free-standing ultrathin Bi nanosheets from Bi nanoparticles. Highly crystalline Bi nanosheets with thickness as low as ≈2 nm and area of more than several micrometers are successfully fabricated on silicon substrates. The ultrathin Bi nanosheets exhibit morphology and structural dependent enhanced broad range photoemission in visible region of spectrum. Our cost-effective hot-pressing strategy may open an insight for production, application, and deficient fundamental understanding of other 2D semimetals/metalloids and noble metals.