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1.
Article in English | MEDLINE | ID: mdl-38881214

ABSTRACT

Plant-mediated biosynthesis of nanoparticles is a green method that allows synthesis in one-pot process. Synthesis of gold nanoparticles with plant extracts has gained interest in the field of biomedicine due to its variety of applications. This study presents the synthesis via green chemistry of gold nanoparticles (AuNPs) using the methanol extract of Moringa oleifera seeds. The AuNPs were synthesized at room temperature. UV-Vis spectroscopy confirmed the formation of AuNPs by identifying the surface plasmon resonance located at 546 nm. TEM analysis shows spherical nanoparticles. FTIR analysis demonstrated the presence of specific bioactive molecules responsible for the Au3+ ion reduction process. The antioxidant activity of the nanoparticles was evaluated on the stabilization of the DPPH radical (1,1-diphenyl-2-picrylhydrazyl, 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl). The antimicrobial activity analysis was developed by broth microdilution method at different concentrations against Escherichia coli and Staphylococcus aureus. Minimum inhibitory concentration were 400 µg/mL and 200 µg/mL, respectively. A549 lung cancer cell proliferation was measured according to the MTT protocol, indicating a dose-dependent response and a IC50 of 163.9 ± 13.27 µg/mL. The AuNPs synthesized using M. oleifera seeds showed promise as active materials for antimicrobial or anticancer products.


Subject(s)
Anti-Bacterial Agents , Antioxidants , Gold , Green Chemistry Technology , Lung Neoplasms , Metal Nanoparticles , Moringa oleifera , Plant Extracts , Seeds , Staphylococcus aureus , Moringa oleifera/chemistry , Metal Nanoparticles/chemistry , Gold/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Plant Extracts/pharmacology , Plant Extracts/chemistry , Seeds/chemistry , Antioxidants/pharmacology , Antioxidants/chemistry , Green Chemistry Technology/methods , Humans , Staphylococcus aureus/drug effects , Lung Neoplasms/drug therapy , Microbial Sensitivity Tests , Escherichia coli/drug effects , A549 Cells
2.
J Physiol ; 602(7): 1405-1426, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38457332

ABSTRACT

Ocular Surface (OS) somatosensory innervation detects external stimuli producing perceptions, such as pain or dryness, the most relevant symptoms in many OS pathologies. Nevertheless, little is known about the central nervous system circuits involved in these perceptions, and how they integrate multimodal inputs in general. Here, we aim to describe the thalamic and cortical activity in response to OS stimulation of different modalities. Electrophysiological extracellular recordings in anaesthetized rats were used to record neural activity, while saline drops at different temperatures were applied to stimulate the OS. Neurons were recorded in the ophthalmic branch of the trigeminal ganglion (TG, 49 units), the thalamic VPM-POm nuclei representing the face (Th, 69 units) and the primary somatosensory cortex (S1, 101 units). The precise locations for Th and S1 neurons receiving OS information are reported here for the first time. Interestingly, all recorded nuclei encode modality both at the single neuron and population levels, with noxious stimulation producing a qualitatively different activity profile from other modalities. Moreover, neurons responding to new combinations of stimulus modalities not present in the peripheral TG subsequently appear in Th and S1, being organized in space through the formation of clusters. Besides, neurons that present higher multimodality display higher spontaneous activity. These results constitute the first anatomical and functional characterization of the thalamocortical representation of the OS. Furthermore, they provide insight into how information from different modalities gets integrated from the peripheral nervous system into the complex cortical networks of the brain. KEY POINTS: Anatomical location of thalamic and cortical ocular surface representation. Thalamic and cortical neuronal responses to multimodal stimulation of the ocular surface. Increasing functional complexity along trigeminal neuroaxis. Proposal of a new perspective on how peripheral activity shapes central nervous system function.


Subject(s)
Thalamic Nuclei , Thalamus , Rats , Animals , Thalamus/physiology , Thalamic Nuclei/physiology , Neurons/physiology , Pain , Face , Somatosensory Cortex/physiology
3.
Article in English | MEDLINE | ID: mdl-38479676

ABSTRACT

To assess the impact of glyphosate and 2,4-D herbicides, as well as the insecticide imidacloprid, both individually and in combination, the gills of adult zebrafish were used due to their intimate interaction with chemicals diluted in water. Bioassays were performed exposing the animals to the different pesticides and their mixture for 96 h. The behavior of the fish was analyzed, a histological examination of the gills was carried out, and the genotoxic effects were also analyzed by means of the comet assay (CA) and the change in the expression profiles of genes involved in the pathways of the oxidative stress and cellular apoptosis. The length traveled and the average speed of the control fish, compared to those exposed to the pesticides and mainly those exposed to the mixture, were significantly greater. All the groups exposed individually exhibited a decrease in thigmotaxis time, indicating a reduction in the behavior of protecting themselves from predators. Histological analysis revealed significant differences in the structures of the gill tissues. The quantification of the histological lesions showed mild lesions in the fish exposed to imidacloprid, moderate to severe lesions for glyphosate, and severe lesions in the case of 2,4-D and the mixture of pesticides. The CA revealed the sensitivity of gill cells to DNA damage following exposure to glyphosate, 2,4-D, imidacloprid and the mixture. Finally, both genes involved in the oxidative stress pathway and those related to the cell apoptosis pathway were overexpressed, while the ogg1 gene, involved in DNA repair, was downregulated.


Subject(s)
Neonicotinoids , Nitro Compounds , Pesticides , Water Pollutants, Chemical , Animals , Pesticides/toxicity , Zebrafish/genetics , Zebrafish/metabolism , Glyphosate , DNA Damage , 2,4-Dichlorophenoxyacetic Acid , RNA, Messenger/metabolism , Gills/metabolism , Water Pollutants, Chemical/metabolism
4.
BMC Nutr ; 10(1): 33, 2024 Feb 26.
Article in English | MEDLINE | ID: mdl-38409182

ABSTRACT

OBJECTIVE: To measure dietary and urinary changes in sodium (Na) intake and excretion through the implementation of family gardens with aromatic herbs and workshops for cooking, using the herbs as a substitute for salt and seasoning powder. METHODS: Thirty-five participants from a neighborhood of Mexico City were included. A general questionnaire was administered to collect information on sociodemographic factors. At baseline and 3 months later, a dietary evaluation was conducted, and 24-hour urine samples were collected. Food items reported were classified according to the NOVA classification. Visits to participants´ houses were conducted to measure the amount of salt and seasoning powder added to food during the preparation of meals as well as a home food inventory. All participants were given a family garden with 6 aromatic herbs and a recipe book. The intervention included 7 cooking and 3 garden care workshops. Qualitative information on the experience was also collected. Linear regression models were run in order to estimate the contribution of each NOVA group, salt, and seasoning powder to total dietary Na intake. RESULTS: Participants were 44 years old on average and were mainly women (91.4%). The participation compliance in the workshops was 69.5%. After 3 months, there was a Na intake mean reduction of 976 mg. There was also a reduction in the excreted urinary Na of 325 mg per day. CONCLUSION: A positive level of involvement in this program had a direct influence on dietary habits to lower Na consumption.

6.
Drug Chem Toxicol ; 47(1): 60-66, 2024 Jan.
Article in English | MEDLINE | ID: mdl-36912201

ABSTRACT

Endocrine disruptors, such as estrogen, are chemical substances with the potential to alter the hormonal balance of organisms. Their origin can be natural or artificial, and they can act at very low doses. The estrogen 17α-ethinylestradiol (EE2) is used worldwide as an oral contraceptive and is a potential contaminant in aquatic ecosystems. It is well documented that these environmental pollutants can act directly or indirectly on the reproductive system, impairing development and fertility. However, little is known about the alteration of the cell oxidative status induced by EE2. The main objective of this study was to evaluate the effect on the gill cells of adult zebrafish exposed in vivo to EE2, analyzing cell histology, DNA damage and the expression levels of genes encoding the main enzymes involved in oxidative stress pathways. The histological study showed that EE2 produces moderate to high damage to the gill tissue, an increase in gill cell DNA damage and the mRNA levels of the genes corresponding to the manganese superoxide dismutase (Mn-sod) and catalase (cat) after exposure to 5 ng/L EE2. The results indicate that EE2 causes tissue alterations, DNA damage and oxidative stress. EE2 produced important alterations in the gills, a fundamental organ for the survival of fish. There is a clear need for further research on the ecological consequences of EDCs on non-target organisms.


Subject(s)
Water Pollutants, Chemical , Zebrafish , Animals , Zebrafish/genetics , Antioxidants/pharmacology , Gills , Ecosystem , Ethinyl Estradiol/toxicity , Estrogens/pharmacology , DNA Damage , Water Pollutants, Chemical/toxicity
7.
Rev Sci Instrum ; 94(4)2023 Apr 01.
Article in English | MEDLINE | ID: mdl-38081255

ABSTRACT

Understanding the micro-mechanisms underlying the localized-ductile transition (LDT) as well as the brittle-plastic transition (BPT) has become crucial for our wider understanding of crustal processes and seismicity. Given how difficult in situ observations of these transitions are to perform, laboratory experiments might be our only way to investigate the processes active under these conditions (high T and high P). Here, we present Triaxial AppaRatus for GEoThermal energy, a new gas-based triaxial apparatus located at EPFL in Switzerland that was specifically designed to operate under conditions where both the LDT and BPT can occur in geomaterials. We show that the machine is capable of deforming rock samples at confining pressures of up to 400 MPa, temperatures of up to 800 °C, and pore pressures (liquid or gas) of up to 300 MPa while keeping the temperature gradient along samples of 40 mm in length and 20 mm in diameter minimal (less than 30 at 700 °C). Most importantly, the maximum load is 1000 kN (stresses as high as 2.2 GPa on 24 mm samples and 3 GPa on 20 mm samples), allowing for the deformation of very competent rock samples. Moreover, during deformation, the pair of syringe pore pressure pumps allow for continuous permeability or dilatancy recording. We benchmarked our machine against existing data in the literature and show that it accurately and precisely records stress, strain, permeability, pressure, and temperature.

8.
Invest Ophthalmol Vis Sci ; 64(14): 12, 2023 11 01.
Article in English | MEDLINE | ID: mdl-37938935

ABSTRACT

Purpose: The purpose of this study was to analyze the differences in corneal sensory nerve functionality in young asymptomatic (CL-A) and symptomatic (CL-S) contact lens (CL) users. Methods: CL wearers (23.8 ± 1.0 years, n = 31) were classified as CL-S with an Ocular Surface Disease Index (OSDI) ≥ 13 (n = 14) or CL-A. Users of eye glasses (EG; 24.5 ± 0.8 years, n = 29) with OSDI < 13 participated as controls. The sensations evoked by mechanical, chemical (gas esthesiometer), and cold (4°C saline drops) stimuli were measured using the Visual Analogue Scales (VASs). Moreover, tear volume, tear break up time (TBUT), blinking frequency (BF), and ocular surface temperature (OST; IR thermography) were also measured. Results: Mechanical and chemical stimuli produced similar scores in the CL-A and EG participants, although the CL-A subjects referred to stronger irritation (p < 0.05). Likewise, the VAS intensity in response to cold stimuli did not differ between CL-A and EG subjects, while the ability to detect cold was significantly worse in CL-S users (p < 0.05). CL-A users had a similar tear volume, a higher BF (p < 0.01) and shorter TBUT (p < 0.001) to EG wearers, and blinking and TBUT were also altered significantly in CL-S users (p < 0.01). Interestingly, the OST was significantly lower in CL-A users (p < 0.05) than in EG wearers, but not in CL-S users. Conclusions: Using CLs modifies corneal sensitivity, blinking and tearing in young volunteers. Even if they have yet to develop clinical signs of inflammation, they display changes in corneal sensitivity consistent with the sensitization of corneal nociceptors and the inhibition cold thermoreceptors, phenomena that occur under inflammatory conditions. The differences in corneal sensitivity and OST between CL-A and CL-S users could reflect the extent of nerve damage and inflammation at the ocular surface.


Subject(s)
Contact Lenses, Hydrophilic , Contact Lenses , Dry Eye Syndromes , Lacrimal Apparatus Diseases , Humans , Cornea/physiology , Blinking , Tears , Inflammation , Contact Lenses, Hydrophilic/adverse effects , Dry Eye Syndromes/etiology
9.
Int J Mol Sci ; 24(16)2023 Aug 09.
Article in English | MEDLINE | ID: mdl-37628800

ABSTRACT

The role of TRPA1 in the thermosensitivity of the corneal cold thermoreceptor nerve endings was studied in young and aged mice. The contribution of the TRPA1-dependent activity to basal tearing and thermally-evoked blink was also explored. The corneal cold thermoreceptors' activity was recorded extracellularly in young (5-month-old) and aged (18-month-old) C57BL/6WT (WT) and TRPA1-/- knockout (TRPA1-KO) mice at basal temperature (34 °C) and during cooling (15 °C) and heating (45 °C) ramps. The blink response to cold and heat stimulation of the ocular surface and the basal tearing rate were also measured in young animals using orbicularis oculi muscle electromyography (OOemg) and phenol red threads, respectively. The background activity at 34 °C and the cooling- and heating-evoked responses of the cold thermoreceptors were similar in WT and TRPA1-KO animals, no matter the age. Similar to the aged WT mice, in the young and aged TRPA1-KO mice, most of the cold thermoreceptors presented low frequency background activity, a low cooling threshold, and a sluggish response to heating. The amplitude and duration of the OOemg signals correlated with the magnitude of the induced thermal change in the WT but not in the TRPA1-KO mice. The basal tearing was similar in the TRPA1-KO and WT mice. The electrophysiological data suggest that the TRPA1-dependent nerve activity, which declines with age, contributes to detecting the warming of the ocular surface and also to integrating the thermally-evoked reflex blink.


Subject(s)
Cornea , Eyelids , Animals , Mice , Mice, Inbred C57BL , Reflex , Cardiac Electrophysiology
10.
Int J Mol Sci ; 24(16)2023 Aug 21.
Article in English | MEDLINE | ID: mdl-37629206

ABSTRACT

Cyclosporine A (CsA) is used for the treatment of dry eye (DE) with good clinical results, improving tear secretion and decreasing subjective symptoms. These effects are attributed to the improved tear film dynamics, but there are no data on the effect of CsA on the abnormal sensory nerve activity characteristic in DE. Our purpose was to evaluate the CsA effect on the enhanced activity of corneal cold thermoreceptors in a tear-deficient DE animal model using in vitro extracellular recording of cold thermoreceptors nerve terminal impulses (NTIs) before and in the presence of CsA. NTI shape was also analyzed. Blinking frequency and tearing rate were also measured in awake animals before and after topical CsA. CsA increased the tearing and blinking of treated animals. CsA significantly decreased the peak response to cold of cold thermoreceptors. Neither their spontaneous NTIs discharge rate nor their cooling threshold were modified. CsA also seemed to reverse some of the changes in NTI shape induced by tear deficiency. These data suggest that, at least in part, the beneficial clinical effects of CsA in DE can be attributed to a direct effect on sensory nerve endings, although the precise mechanisms underlying this effect need further studies to be fully clarified.


Subject(s)
Cyclosporine , Lacrimal Apparatus Diseases , Animals , Cyclosporine/pharmacology , Nerve Endings , Thermoreceptors , Sensory Receptor Cells , Action Potentials
11.
Reumatismo ; 75(2)2023 Jul 17.
Article in English | MEDLINE | ID: mdl-37462131

ABSTRACT

Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by a heterogeneous clinical picture that makes the diagnosis and follow-up of these patients difficult. This study aimed to identify correlations between clinical, immunological, and genetic biomarkers and clinical manifestations in SLE. A retrospective study of data from medical records and immunological and genetic studies of SLE patients in Paraguay was carried out. A descriptive analysis was performed based on the type of variable. Human leukocyte antigen (HLA) allele frequencies (DPA1, DPB1, DQA1, DQB1, and DRB1) were calculated, and univariate logistic regression analyses were performed between each of the explanatory variables and the presence or absence of each phenotype. Odds ratios, 95% confidence intervals, and p values were recorded. Associations with p<0.05 were considered statistically significant. 104 SLE patients were included: 86% were female, with a mean age of 32.80±10.36 years. An association was identified between anti-double stranded DNA (anti-dsDNA) and the presence of the renal phenotype and between anti-dsDNA and the absence of the joint and hematological phenotypes. Immunoglobulin M isotype rheumatoid factor was associated with the absence of a renal phenotype. HLA-DQB1*02:02 and HLA-DRB1*07:01 were associated with the cutaneous phenotype. An association was identified between age at disease onset over 30 years and the presence of the joint phenotype. No other associations were identified. Potential clinical, immunological, and genetic biomarkers of phenotypes have been identified in SLE Paraguayan patients.


Subject(s)
Lupus Erythematosus, Systemic , Adult , Female , Humans , Male , Young Adult , Alleles , Biomarkers , Genetic Predisposition to Disease , HLA-DRB1 Chains/genetics , Lupus Erythematosus, Systemic/diagnosis , Lupus Erythematosus, Systemic/ethnology , Lupus Erythematosus, Systemic/genetics , Paraguay/epidemiology , Phenotype , Retrospective Studies , Middle Aged
12.
Sci Adv ; 9(24): eadg6075, 2023 06 16.
Article in English | MEDLINE | ID: mdl-37315129

ABSTRACT

Amino acid crystals are an attractive piezoelectric material as they have an ultrahigh piezoelectric coefficient and have an appealing safety profile for medical implant applications. Unfortunately, solvent-cast films made from glycine crystals are brittle, quickly dissolve in body fluid, and lack crystal orientation control, reducing the overall piezoelectric effect. Here, we present a material processing strategy to create biodegradable, flexible, and piezoelectric nanofibers of glycine crystals embedded inside polycaprolactone (PCL). The glycine-PCL nanofiber film exhibits stable piezoelectric performance with a high ultrasound output of 334 kPa [under 0.15 voltage root-mean-square (Vrms)], which outperforms the state-of-the-art biodegradable transducers. We use this material to fabricate a biodegradable ultrasound transducer for facilitating the delivery of chemotherapeutic drug to the brain. The device remarkably enhances the animal survival time (twofold) in mice-bearing orthotopic glioblastoma models. The piezoelectric glycine-PCL presented here could offer an excellent platform not only for glioblastoma therapy but also for developing medical implantation fields.


Subject(s)
Glioblastoma , Nanofibers , Animals , Mice , Amino Acids , Glycine , Brain
14.
Chem Commun (Camb) ; 59(11): 1485-1488, 2023 Feb 02.
Article in English | MEDLINE | ID: mdl-36655734

ABSTRACT

Perovskite materials passivated by chiral ligands have recently shown unique chiroptical activity with promising optoelectronic applications. However, the ligands have been limited to chiral amines. Here, chiral phosphate molecules have been exploited to synthesize CsPbBr3 nanoplatelets. The nanoplatelets showed a distinct circular dichroism signal and maintained their chiroptical properties after purification with anti-solvent.

15.
Ocul Surf ; 27: 80-88, 2023 01.
Article in English | MEDLINE | ID: mdl-36396021

ABSTRACT

PURPOSE: To measure, the tear flow changes evoked in healthy subjects and dry eye disease (DED) patients by controlled sensory stimulation of the eye surface with i-Onion™, a new stimulation device. METHODS: Sensory corneal nerves were stimulated with an instrument (i-Onion™) that ejects puffs of CO2 gas (99.9%) at 200 ml·min-1 for 3s, delivered 5 mm from the cornea. Using Schirmer test strips, tear volumes were measured over 3 min in the cornea of one eye before (basal tear volume -BTV) and in the other eye after stimulation of the sensory nerves with CO2 (stimulated tear volume -STV). These measurements were obtained from a control group of adults of either sex (17 students aged 20-30 and 29 subjects without signs of dry eye aged 25-61), a cohort of DED patients (aged 34-75) that included 12 asymptomatic, suspected DED subjects (Schirmer <7 mm and/or TBUT <10s), and 30 Sjögren's syndrome (SS) patients. RESULTS: CO2 stimulation significantly increased the tear volume (BTV = 14.6 ± 1.0 mm, STV = 19.0 ± 1.1 mm: n = 46) in 78% of control subjects, reflecting a mean tear reserve volume (TRV = STV-BTV) of 4.4 ± 0.8 mm. Individual differences were wide, and while no increase in reflex tearing was evoked in 30% of subjects with a BTV >10 mm, the remaining 70% responded vigorously to stimulation, even those with a BTV >18 mm. Asymptomatic DED subjects displayed weaker responses to CO2 stimulation, with lower STVs. Both the BTV and STV of SS patients were low, significantly below those of the healthy controls. CONCLUSIONS: Measuring the rise in reflex tearing volume evoked by controlled corneal stimulation provides objective information about the tear glands' secretory capacity in health and disease.


Subject(s)
Dry Eye Syndromes , Sjogren's Syndrome , Adult , Humans , Carbon Dioxide , Dry Eye Syndromes/diagnosis , Sjogren's Syndrome/diagnosis , Tears/physiology , Cornea
16.
Rev. chil. neuro-psiquiatr ; 60(4): 413-421, dic. 2022. tab, graf
Article in Spanish | LILACS | ID: biblio-1423704

ABSTRACT

Introducción: las sustancias psicoactivas han formado parte de la existencia humana por miles de años, han sido empleadas con distintos fines, consolidando su uso y abuso durante los últimos años como una condición altamente prevalente en la sociedad. Actualmente, existen gran cantidad de sustancias y, así mismo, diversas formas de clasificación. En términos de prevalencia mundial hasta el momento no hay un estándar de oro que permita medir de manera exacta el consumo según cada región geográfica, lo que dificulta el estudio y constituye un desafío al momento de realizar comparaciones entre regiones. No obstante, en términos de prevalencia mundial, la sustancia más consumida es el alcohol, seguida por cannabis, opioides, anfetaminas y cocaína respectivamente. Objetivo: caracterizar pacientes adultos del policlínico de salud mental del Hospital Hernán Henríquez Aravena con diagnóstico relacionado al consumo de sustancias y establecer las principales sustancias consumidas. Materiales y Método: se realizó un estudio descriptivo transversal en la población objetivo mediante revisión de fichas clínicas de pacientes adultos atendidos en policlínico de salud mental del Hospital Hernán Henríquez Aravena, durante los años 2018, 2019, 2020. Los antecedentes recolectados del estudio se analizaron según la población general y se compararon según género. Resultados: en la muestra estudiada, 73.2% de los consumidores son de sexo masculino, siendo el alcohol la sustancia de mayor consumo, seguida por cocaína, marihuana y benzodiacepinas.


Introduction: psychoactive substances have been part of the existence of humanity for thousands of years and have been used for different purposes, consolidating its use and abuse in recent years as a highly prevalent condition in our society. They are a large number of substances, and also various forms of classification. In terms of world prevalence, to date, there is no gold standard method that allows the exact measurement of substance consumption to each geographical region, which makes the study difficult and constitutes a challenge when making comparisons between regions. However, in terms of world prevalence, the most consumed substance is alcohol, followed by cannabis, opioids, amphetamines, and cocaine respectively. Objective: characterize adult patients of the mental health polyclinic of the Hernán Henríquez Aravena Hospital with a diagnosis related to substance use and establish the main substances consumed. Material and Method: A cross-sectional descriptive study was carried out in the target population by reviewing the clinical records of adult patients treated at the mental health polyclinic of the Hernán Henríquez Aravena Hospital, during the years 2018, 2019, and 2020. The antecedents collected from the study were analyzed according to the general population and compared according to gender. Results: In the sample studied, 73.2% of the users are male, alcohol being the substance most consumed, followed by cocaine, marijuana, and benzodiazepines


Subject(s)
Humans , Male , Female , Adult , Substance-Related Disorders/epidemiology , Tobacco Use Disorder/epidemiology , Alcohol Drinking/epidemiology , Chile , Sex Factors , Marijuana Abuse/epidemiology , Cross-Sectional Studies , Age Factors , Diagnosis, Dual (Psychiatry) , Substance-Related Disorders/therapy , Hospitals, Public , Mental Health Services
17.
Soft Matter ; 18(42): 8165-8174, 2022 Nov 02.
Article in English | MEDLINE | ID: mdl-36263742

ABSTRACT

Manipulating molecular and supramolecular interactions within cellulose nanocrystals (CNCs) to introduce different levels of assemblies combined with multiple functionalities is required for the development of degradable smart materials from renewable resources. To attain hierarchical structures and stimuli-responsive properties, a new class of liquid crystalline cellulosic hybrid materials is synthesized. Herein, main-chain rigid-rod-like oxidized cellulose (CNC-COOH) is prepared from a Cellulose Whatman filter paper (Cellulose W.P.) by acid hydrolysis and oxidized using 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO). Thermotropic LC molecule, 4-cyano-4'-hydroxybiphenyl with a 12-methylene spacer (CB12-OH) is grafted onto the carboxylic acid group of CNC-COOH via Steglich esterification. The liquid crystalline functionalized CNCs cellulose nanocrystals (CNC-COO-CB12) are readily soluble in DMSO and ionic liquids. The extent of functionalization and structure of CNC-COO-CB12 are confirmed by solution-state 1H NMR and supported by other characterization techniques. We investigate the interplay of liquid crystalline orientational order of CNCs and cyanobiphenyl (CB12), and the supramolecular hydrogen bonding of CNCs within CNC-COO-CB12 and compare it with CNC-COOH. The introduction of thermotropic CB12 side chains onto rigid-rod CNCs shows the exclusive formation of smectic mesophases from the assemblies of CB12 with the absence of the cholesteric mesophase typically observed from CNC-COOH as verified by temperature-controlled SAXS (T-SAXS). This is further verified by UV-visible and SEM studies that show CNC-COO-CB12 forms smectic domains while CNC-COOH forms a visible light reflecting cholesteric mesophase in dried films. Thus, the interplay of liquid crystalline order of CNCs and CB12 and supramolecular hydrogen bonding of CNCs results in ordered, smectic-mesostructured CNCs for use in stimuli-responsive functional materials.

18.
Public Health Pract (Oxf) ; 4: 100313, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36090797

ABSTRACT

Objectives: In a context of COVID-19 vaccine shortages, this study sought to evaluate the safety and efficacy of receiving one dose of Gam-COVID-Vac rAd26 followed by a second COVID-19 vaccine dose of either Gam-COVID-Vac rAd5, ChAdOx1 nCoV-19 or BBIBP-CorV in a cohort of older adults. Study design: Single-centre, randomised, open label, non-inferiority trial. Methods: Adults aged ≥65 years who had received one dose of Gam-COVID-Vac rAd26 were randomised in a 1:1:1 ratio to receive a second-dose COVID-19 vaccination of either Gam-COVID-Vac rAd5, ChAdOx1 nCoV-19 or BBIBP-CorV. The primary outcome was the assessment of the humoral immune response to vaccination (i.e. antibody titres of SARS-CoV-2 spike protein at 28 days after second-dose vaccination). In addition, neutralising antibody titres at day 28 for the three schedules were measured. Results: Of 85 participants who were enrolled in the study between 26 and July 30, 2021, 31 individuals were randomised to receive Gam-COVID-Vac rAd5, 27 to ChAdOx1 nCoV-19 and 27 to BBIBP-CorV. The mean age of participants was 68.2 years (SD 2.9) and 49 (57.6%) were female. Participants who received Gam-COVID-Vac rAd5 and ChAdOx1 nCoV1-19 showed significantly increased anti-S titres at 28 days after second-dose vaccination, but this magnitude of difference was not observed for those who received BBIBP-CorV. The ratio between the geometric mean at day 28 and baseline within each group was 11.8 (6.98-19.89) among patients assigned to Gam-COVID-Vac rAd26/rAd5, 4.81 (2.14-10.81) for the rAd26/ChAdOx1 nCoV-19 group and 1.53 (0.74-3.20) for the rAd26/BBIBP-CorV group. All of the schedules were shown to be safe. Conclusions: The findings in this study contribute to the scarce information published on the safety and immunogenicity of Gam-COVID-Vac heterologous regimens and will help the development of guidelines and vaccine programme management.

19.
Front Neurol ; 13: 944779, 2022.
Article in English | MEDLINE | ID: mdl-36016546

ABSTRACT

Introduction: We aimed to determine whether the degree of collateral circulation is associated with blood pressure at admission in acute ischemic stroke patients treated with endovascular treatment and to determine its prognostic value. Methods: We evaluated patients with anterior large vessel occlusion treated with endovascular treatment in a single-center prospective registry. We collected clinical and radiological data. Automated and validated software (Brainomix Ltd., Oxford, UK) was used to generate the collateral score (CS) from the baseline single-phase CT angiography: 0, filling of ≤10% of the occluded MCA territory; 1, 11-50%; 2, 51-90%; 3, >90%. When dichotomized, we considered that CS was good (CS = 2-3), or poor (CS = 0-1). We performed bivariate and multivariable ordinal logistic regression analysis to predict CS categories in our population. The secondary outcome was to determine the influence of automated CS on functional outcome at 3 months. We defined favorable functional outcomes as mRS 0-2 at 3 months. Results: We included 101 patients with a mean age of 72.1 ± 13.1 years and 57 (56.4%) of them were women. We classified patients into 4 groups according to the CS: 7 patients (6.9%) as CS = 0, 15 (14.9%) as CS = 1, 43 (42.6%) as CS = 2 and 36 (35.6%) as CS = 3. Admission systolic blood pressure [aOR per 10 mmHg increase 0.79 (95% CI 0.68-0.92)] and higher baseline NIHSS [aOR 0.90 (95% CI, 0.84-0.96)] were associated with a worse CS. The OR of improving 1 point on the 3-month mRS was 1.63 (95% CI, 1.10-2.44) favoring a better CS (p = 0.016). Conclusion: In acute ischemic stroke patients with anterior large vessel occlusion treated with endovascular treatment, admission systolic blood pressure was inversely associated with the automated scoring of CS on baseline CT angiography. Moreover, a good CS was associated with a favorable outcome.

20.
Int J Mol Sci ; 23(13)2022 Jun 29.
Article in English | MEDLINE | ID: mdl-35806263

ABSTRACT

This study aimed to develop Ca2+ doped ZnO nanoparticles (NPs) and investigate their antibacterial properties against microorganisms of dental interest. Zn-Ca NPs were synthesized by the sol-gel method with different concentrations of Ca2+ (1, 3, and 5 wt. %) and subsequently characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-vis spectroscopy and Fourier transform infrared spectroscopy (FT-IR). The Kirby-Bauer method was used to measure antibacterial effects. NPs showed the wurzite phase of ZnO and bandgap energies (Eg) from 2.99 to 3.04 eV. SEM analysis showed an average particle size of 80 to 160 nm. The treatments that presented the best antibacterial activity were Zn-Ca 3% and Zn-Ca 5%. ZnO NPs represent an alternative to generate and improve materials with antibacterial capacity for dental applications.


Subject(s)
Metal Nanoparticles , Nanocomposites , Zinc Oxide , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Metal Nanoparticles/chemistry , Microbial Sensitivity Tests , Nanocomposites/chemistry , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction , Zinc/pharmacology , Zinc Oxide/chemistry , Zinc Oxide/pharmacology
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