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1.
Anal Chem ; 96(18): 7179-7186, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38661266

RESUMEN

This study uses real-time monitoring, at microsecond time scales, with a charge-sensing particle detector to investigate the evaporation and fission processes of methanol/micrometer-sized polystyrene beads (PS beads) droplets and bacterial particles droplets generated via electrospray ionization (ESI) under elevated temperatures. By incrementally raising capillary temperatures, the solvent, such as methanol on 0.75 µm PS beads, experiences partial evaporation. Further temperature increase induces fission, and methanol molecules continue to evaporate until PS ions are detected after this range. Similar partial evaporation is observed on 3 µm PS beads. However, the shorter period of the fission temperature range is necessary compared to 0.75 µm PS beads. For the spherical-shaped bacterium, Staphylococcus aureus, the desolvation process shows a similar fission period as compared to 0.75 µm PS beads. Comparably, the rod-shaped bacteria, Escherichia coli EC11303, and E. coli strain W have shorter fission periods than S. aureus. This research provides insights into the evaporation and fission mechanisms of ESI droplets containing different sizes and shapes of micrometer-sized particles, contributing to a better understanding of gaseous macroion formation.


Asunto(s)
Escherichia coli , Poliestirenos , Espectrometría de Masa por Ionización de Electrospray , Staphylococcus aureus , Poliestirenos/química , Escherichia coli/química , Tamaño de la Partícula , Temperatura , Volatilización , Metanol/química , Microesferas
2.
Environ Sci Technol ; 58(20): 8631-8642, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38728100

RESUMEN

The global trade of plastic waste has raised environmental concerns, especially regarding pollution in waste-importing countries. However, the overall environmental contribution remains unclear due to uncertain treatment shares between handling plastic waste abroad and domestically. Here, we conduct a life cycle assessment of global plastic waste trade in 2022 across 18 countries and six plastic waste types, alongside three "nontrade" counterfactual scenarios. By considering the required cycling rate, which balances importers' costs and recycling revenues, we find that the trade resulted in lower environmental impacts than treating domestically with the average treatment mix. The trade scenario alone reduced climate change impact by 2.85 million tonnes of CO2 equivalent and mitigated damages to ecosystem quality, human health, and resource availability by 12 species-years, 6200 disability-adjusted life years (DALYs), and 1.4 billion United States dollars (USD in 2013), respectively. These results underscore the significance of recognizing plastic waste trade as a pivotal factor in regulating global secondary plastic production when formulating a global plastics treaty.


Asunto(s)
Plásticos , Reciclaje , Comercio , Humanos , Cambio Climático , Ambiente
3.
Environ Res ; 252(Pt 1): 118604, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38548254

RESUMEN

The effective degradation of recalcitrant lignocellulose has emerged as a bottleneck for the humification of compost, and strategies are required to improve the efficiency of bagasse composting. Bioaugmentation is a promising method for promoting compost maturation and improving the quality of final compost. In this study, the bioaugmentation effects of microbial inoculants on humic acid (HA) formation during lignocellulosic composting were explored. In the inoculated group, the maximum temperature was increased to 72.5 °C, and the phenol-protein condensation and Maillard humification pathways were enhanced, thus increasing the HA content by 43.85%. After inoculation, the intensity of the microbial community interactions increased, particularly for fungi (1.4-fold). Macrogenomic analysis revealed that inoculation enriched thermophilic bacteria and lignocellulose-degrading fungi and increased the activity of carbohydrate-active enzymes and related metabolic functions, which effectively disrupted the recalcitrant structure of lignocellulose to achieve a high humification degree. Spearman correlation analysis indicated that Stappia of the Proteobacteria phylum, Ilumatobacter of the Actinomycetes phylum, and eleven genera of Ascomycota were the main HA producers. This study provides new ideas for bagasse treatment and recycling and realizing the comprehensive use of resources.


Asunto(s)
Celulosa , Compostaje , Sustancias Húmicas , Estiércol , Sustancias Húmicas/análisis , Estiércol/microbiología , Celulosa/metabolismo , Compostaje/métodos , Animales , Bovinos , Bacterias/metabolismo , Lignina/metabolismo , Hongos/metabolismo
4.
Caries Res ; 58(3): 173-183, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38402857

RESUMEN

INTRODUCTION: This study aimed to investigate the remineralisation effect of combined use of a bioinspired self-assembling peptide (P26) and fluoride varnish on artificial early enamel caries lesions. METHODS: Bovine enamel blocks with artificial early enamel caries lesions were prepared. The blocks were randomly allocated to four experimental groups to receive the following treatments: A = P26 + fluoride varnish, B = P26, C = fluoride varnish, and D. distilled water (negative control). The treated blocks were subjected to pH cycling. Enamel blocks were collected at time points of 7 days (d7) and 21 days (d21). The mineral gain, elemental analysis and crystal characteristics of the caries lesion were assessed by micro-computed tomography, scanning electron microscopy with energy dispersive X-ray and X-ray diffraction (XRD), respectively. RESULTS: The mean ± standard deviation of mineral gain of group A to D were 17.4 ± 4.2%, 10.7 ± 2.2%, 10.1 ± 1.2%, and 6.8 ± 0.5% at d7, respectively, and 15.2 ± 2.6%, 8.7 ± 3.1%, 9.7 ± 1.2%, and 7.8 ± 2.3% at d21, respectively. A significant higher mineral gain was observed in group A when compared to other groups at both d7 and d21 (p < 0.05). The calcium-to-phosphate ratio remained consistent across all groups, ranging between 1.2 and 1.4. XRD analysis indicated that crystal composition on the surfaces was apatite for all groups. CONCLUSION: In conclusion, the present study provided a first indication of better remineralisation effects of the combined use of the bioinspired self-assembling peptide P26 and fluoride varnish compared to the effects of the respective individual uses of P26 or fluoride varnish.


Asunto(s)
Cariostáticos , Caries Dental , Esmalte Dental , Fluoruros Tópicos , Microscopía Electrónica de Rastreo , Remineralización Dental , Difracción de Rayos X , Remineralización Dental/métodos , Animales , Caries Dental/prevención & control , Bovinos , Esmalte Dental/efectos de los fármacos , Fluoruros Tópicos/farmacología , Técnicas In Vitro , Cariostáticos/farmacología , Cariostáticos/química , Cariostáticos/uso terapéutico , Microtomografía por Rayos X , Péptidos , Espectrometría por Rayos X , Concentración de Iones de Hidrógeno , Fluoruro de Sodio/farmacología , Fluoruro de Sodio/uso terapéutico
5.
J Prosthet Dent ; 132(1): 267.e1-267.e10, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38622046

RESUMEN

STATEMENT OF PROBLEM: Denture stomatitis can pose serious health risks, especially to older people. Chemical denture cleaning agents must be effective, yet not adversely affect the longevity of removable dentures. Ready-to-use (RTU) neutral pH electrolyzed oxidizing water (EOW) is an effective biocide against Candida albicans biofilms on denture resins, but the effects of daily disinfection with EOW on the physical and mechanical properties of resins have not been established. PURPOSE: The purpose of this in vitro study was to investigate the effects of simulated long-term exposure to RTU EOW on the color, surface characteristics, and flexural strength of denture base resins. MATERIAL AND METHODS: Heat-polymerized (HP), 3D printed (3D) and computer-aided design and computer-aided manufacture (CAD-CAM)-milled (CC) denture resin specimens (square: 20×20×3.3 mm; beam: 64×10×3.3 mm) were immersed in tap water (TW), RTU EOW (Neutral Anolyte ANK; Envirolyte; EOW), or a commercial denture cleaning tablet solution (Polident 3-Minute; Glaxo SmithKline; PD), mimicking a 5-minute once daily disinfection routine performed up to 3.0 years. Color and surface roughness were recorded (n=3, squares), and changes in color (∆E00) and surface roughness (∆Ra) were calculated. Flexural strength (n=12, beams) and surface hardness (n=18, beams) were measured with a universal testing machine. The fractured surfaces of specimens were examined by scanning electron microscopy and energy dispersive spectroscopy. Data were assessed by performing the Shapiro-Wilk or D'Agostino and Pearson normality tests. Two-way ANOVA or the Kruskal-Wallis test with a post hoc Tukey HSD or Dunn multiple comparisons (α=.05) was used for statistical analyses. RESULTS: No significant changes were found in either color or surface roughness for HP, 3D, and CC resins after 1.5-year and 3.0-year immersion in any of the agents (P>.05). The surface hardness of 3D resins reduced by 14% with TW and by 23% with EOW and PD at 3.0 years. The flexural strengths of all 3 resins were unaffected by 3.0-year immersion (P>.05). CONCLUSIONS: Simulated long-term immersion disinfection with RTU neutral pH EOW did not adversely affect the physical and mechanical properties of HP or CC denture resins.


Asunto(s)
Bases para Dentadura , Limpiadores de Dentadura , Propiedades de Superficie , Agua , Agua/química , Concentración de Iones de Hidrógeno , Limpiadores de Dentadura/química , Ensayo de Materiales , Resistencia Flexional , Humanos , Materiales Dentales/química , Diseño Asistido por Computadora , Técnicas In Vitro , Electrólisis , Resinas Acrílicas/química , Color , Boratos , Sulfatos
6.
Angew Chem Int Ed Engl ; 63(13): e202318632, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38327029

RESUMEN

Liposomes serve as promising and versatile vehicles for drug delivery. Tracking these nanosized vesicles, particularly in vivo, is crucial for understanding their pharmacokinetics. This study introduces the design and synthesis of three new conjugated electrolyte (CE) molecules, which emit in the second near-infrared window (NIR-II), facilitating deeper tissue penetration. Additionally, these CEs, acting as biomimetics of lipid bilayers, demonstrate superior compatibility with lipid membranes compared to commonly used carbocyanine dyes like DiR. To counteract the aggregation-caused quenching effect, CEs employ a twisted backbone, as such their fluorescence intensities can effectively enhance after a fluorophore multimerization strategy. Notably, a "passive" method was employed to integrate CEs into liposomes during the liposome formation, and membrane incorporation efficiency was significantly promoted to nearly 100%. To validate the in vivo tracking capability, the CE-containing liposomes were functionalized with cyclic arginine-glycine-aspartic acid (cRGD) peptides, serving as tumor-targeting ligands. Clear fluorescent images visualizing tumor site in living mice were captured by collecting the NIR-II emission. Uniquely, these CEs exhibit additional emission peak in visible region, enabling in vitro subcellular analysis using routine confocal microscopy. These results underscore the potential of CEs as a new-generation of membrane-targeting probes to facilitate the liposome-based medicine research.


Asunto(s)
Liposomas , Neoplasias , Ratones , Animales , Liposomas/química , Membrana Dobles de Lípidos/química , Biomimética , Sistemas de Liberación de Medicamentos , Colorantes Fluorescentes/química
7.
Langmuir ; 39(4): 1529-1537, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36683534

RESUMEN

Injectable hydrogels with strong mechanical properties have significant potential for biomedical applications, including the development of electronic skin, intelligent medical robots, as well as tissue engineering. In this study, we report on an injectable hydrogel with notable tensile strength and adhesion properties, achieved through cross-linking thiol-terminated four-arm poly (ethylene glycol) using silver-doped nano-hydroxyapatite, modified with dopamine. Subsequently, the hydrogel was injected in vivo through the perivascular interstitial space of rats. The hydrogel wrapped around the damaged abdominal aortic adventitia, which greatly increases the stress strength of the arterial adventitia. We found that the hydrogel was characterized by excellent biocompatibility, and it induced little immune response over a span of 21 days post-implantation. This simple and minimally invasive vascular protection strategy appears promising for the treatment of vascular diseases, such as abdominal aortic aneurysm (AAA).


Asunto(s)
Adventicia , Hidrogeles , Ratas , Animales , Hidrogeles/farmacología , Inyecciones , Polietilenglicoles/toxicidad , Ingeniería de Tejidos
8.
J Insect Sci ; 23(6)2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-38006418

RESUMEN

Insect gut bacteria play an essential role in the nutritional metabolism, growth, and development of insects. Grasshoppers (Orthoptera) are cellulose-rich plant-feeding pests. Although the biological potential of grasshopper gut microorganisms to assist cellulose decomposition is well established, microbial resources for efficient degradation of cellulose biomass are still scarce and need to be developed. In this study, we used selective media to isolate cellulose-degrading bacteria from the intestines of Atractomorpha sinensis, Trilophidia annulata, Sphingonotus mongolicus, and Calliptamus abbreviatus. Phylogenetic analysis based on the maximum likelihood method using 16S rDNA sequencing sequences to identify bacteria revealed the isolation of 11 strains belonging to 3 genera, including Klebsiella, Aeromonas, and Bacillus. The degradability of the isolates to cellulose was then determined by the DNS colorimetric method, and the results showed that Bacillus had the highest degradation rate. The elucidation of microbial cellulose degradation capacity in grasshoppers not only contributes to the understanding of multiple plant-insect-microbe interactions, but also provides a valuable microbial resource for solving the biomass conversion of cellulose species problem.


Asunto(s)
Saltamontes , Animales , Saltamontes/metabolismo , Filogenia , Celulosa/metabolismo , Bacterias/genética , Biomasa
9.
Int J Mol Sci ; 24(4)2023 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-36835111

RESUMEN

Residual ridge resorption combined with dimensional loss resulting from tooth extraction has a prolonged correlation with early excessive inflammation. Nuclear factor-kappa B (NF-κB) decoy oligodeoxynucleotides (ODNs) are double-stranded DNA sequences capable of downregulating the expression of downstream genes of the NF-κB pathway, which is recognized for regulating prototypical proinflammatory signals, physiological bone metabolism, pathologic bone destruction, and bone regeneration. The aim of this study was to investigate the therapeutic effect of NF-κB decoy ODNs on the extraction sockets of Wistar/ST rats when delivered by poly(lactic-co-glycolic acid) (PLGA) nanospheres. Microcomputed tomography and trabecular bone analysis following treatment with NF-κB decoy ODN-loaded PLGA nanospheres (PLGA-NfDs) demonstrated inhibition of vertical alveolar bone loss with increased bone volume, smoother trabecular bone surface, thicker trabecular bone, larger trabecular number and separation, and fewer bone porosities. Histomorphometric and reverse transcription-quantitative polymerase chain reaction analysis revealed reduced tartrate-resistant acid phosphatase-expressing osteoclasts, interleukin-1ß, tumor necrosis factor-α, receptor activator of NF-κB ligand, turnover rate, and increased transforming growth factor-ß1 immunopositive reactions and relative gene expression. These data demonstrate that local NF-κB decoy ODN transfection via PLGA-NfD can be used to effectively suppress inflammation in a tooth-extraction socket during the healing process, with the potential to accelerate new bone formation.


Asunto(s)
Pérdida de Hueso Alveolar , FN-kappa B , Nanosferas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Animales , Ratas , Pérdida de Hueso Alveolar/tratamiento farmacológico , Proceso Alveolar , Glicoles , Inflamación/metabolismo , Nanosferas/uso terapéutico , FN-kappa B/química , FN-kappa B/farmacología , Oligodesoxirribonucleótidos/farmacología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacología , Ratas Wistar , Microtomografía por Rayos X
10.
J Prosthet Dent ; 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37852858

RESUMEN

STATEMENT OF PROBLEM: The surgical extrusion technique has been advocated for severely damaged teeth as well as for intruded and unerupted teeth. However, a quantitative literature analysis is lacking. PURPOSE: The purpose of this bibliometric analysis was to provide a comprehensive overview of surgical extrusion, assess the applications and outcomes, and evaluate topics for future research. MATERIAL AND METHODS: An electronic search was conducted in leading databases in April 2023. Human studies with surgical tooth extrusion or synonyms in titles or abstracts were included. A bibliographic analysis, co-occurrence analysis, and coupling of publications were performed. The analysis of variance was used to assess the characteristics of the subgroups based on indications. The survival rate was evaluated by using the Kaplan-Meier method in the R software program (α=.05). RESULTS: Fifty-one studies from 1982 to 2023 were included. The Journal of Dental Traumatology and the Journal of Prosthetic Dentistry combined published approximately one-third of the papers and acquired the most citations. The burst detection of keywords revealed 4 popular research topics: the Benex extraction system, chlorhexidine for infection control, rigid or semi-rigid splints to decrease the risk of complications, and novel restorative materials to improve esthetics. An overall survival rate of 96.36% was reported among 316 participants with 330 extruded teeth. No significant differences were found in study types, geographic distribution, year of publication, or citation counts among the 4 subgroups (surgical extrusion for subgingival fractures, extensive caries, intruded teeth, and unerupted teeth). A significant difference was observed among the Kaplan-Meier curves of the 4 subgroups (P=.030). CONCLUSIONS: Surgical extrusion may be used to save otherwise nonrestorable teeth, and the procedure has shown promising survival rates when teeth are properly selected and the procedure is well executed. Subgingival fractures and extensive caries near bone level are the predominant indications, as well as intruded and unerupted teeth. Surgical extrusion is a reliable treatment option to facilitate tooth restoration for severely damaged teeth, especially for maxillary anterior teeth.

11.
BMC Oral Health ; 23(1): 30, 2023 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-36658579

RESUMEN

BACKGROUND: Severe early childhood caries (SECC) is an inflammatory disease with complex pathology. Although changes in the oral microbiota and metabolic profile of patients with SECC have been identified, the salivary metabolites and the relationship between oral bacteria and biochemical metabolism remains unclear. We aimed to analyse alterations in the salivary microbiome and metabolome of children with SECC as well as their correlations. Accordingly, we aimed to explore potential salivary biomarkers in order to gain further insight into the pathophysiology of dental caries. METHODS: We collected 120 saliva samples from 30 children with SECC and 30 children without caries. The microbial community was identified through 16S ribosomal RNA (rRNA) gene high-throughput sequencing. Additionally, we conducted non-targeted metabolomic analysis through ultra-high-performance liquid chromatography combined with quadrupole time-of-flight mass spectrometry to determine the relative metabolite levels and their correlation with the clinical caries status. RESULTS: There was a significant between-group difference in 8 phyla and 32 genera in the microbiome. Further, metabolomic and enrichment analyses revealed significantly altered 32 salivary metabolites in children with dental caries, which involved pathways such as amino acid metabolism, pyrimidine metabolism, purine metabolism, ATP-binding cassette transporters, and cyclic adenosine monophosphate signalling pathway. Moreover, four in vivo differential metabolites (2-benzylmalate, epinephrine, 2-formaminobenzoylacetate, and 3-Indoleacrylic acid) might be jointly applied as biomarkers (area under the curve = 0.734). Furthermore, the caries status was correlated with microorganisms and metabolites. Additionally, Spearman's correlation analysis of differential microorganisms and metabolites revealed that Veillonella, Staphylococcus, Neisseria, and Porphyromonas were closely associated with differential metabolites. CONCLUSION: This study identified different microbial communities and metabolic profiles in saliva, which may be closely related to caries status. Our findings could inform future strategies for personalized caries prevention, detection, and treatment.


Asunto(s)
Caries Dental , Microbiota , Niño , Preescolar , Humanos , Caries Dental/microbiología , Susceptibilidad a Caries Dentarias , Saliva/química , Microbiota/genética , Metaboloma , ARN Ribosómico 16S/genética , Biomarcadores
12.
Mol Cancer ; 21(1): 21, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35042519

RESUMEN

BACKGROUND: The tRNA-derived small RNAs (tsRNAs) are produced in a nuclease-dependent manner in responses to variety of stresses that are common in cancers. We focus on a cancer-enriched tsRNA signature to develop a salivary exosome-based non-invasive biomarker for human esophageal squamous cell carcinoma (ESCC). METHODS: Cancer-enriched small RNAs were identified by RNA sequencing of salivary exosomes obtained from ESCC patients (n = 3) and healthy controls (n = 3) in a pilot study and further validated in discovery cohort (n = 66). A multicenter prospective observational study was conducted in two ESCC high-incidence regions (n = 320 and 200, respectively) using the newly developed biomarker signature. RESULTS: The tsRNA (tRNA-GlyGCC-5) and a previously undocumented small RNA were specifically enriched in salivary exosomes of ESCC patients, ESCC tissues and ESCC cells. The bi-signature composed of these small RNAs was able to discriminate ESCC patients from the controls with high sensitivity (90.50%) and specificity (94.20%). Based on the bi-signature Risk Score for Prognosis (RSP), patients with high-RSP have both shorter overall survival (OS) (HR 4.95, 95%CI 2.90-8.46) and progression-free survival (PFS) (HR 3.69, 95%CI 2.24-6.10) than those with low-RSP. In addition, adjuvant therapy improved OS (HR 0.47, 95%CI 0.29-0.77) and PFS (HR 0.36, 95%CI 0.21-0.62) only for patients with high but not low RSP. These findings are consistent in both training and validation cohort. CONCLUSIONS: The tsRNA-based signature not only has the potential for diagnosis and prognosis but also may serve as a pre-operative biomarker to select patients who would benefit from adjuvant therapy. TRIAL REGISTRATION: A prospective study of diagnosis biomarkers of esophageal squamous cell carcinoma, ChiCTR2000031507 . Registered 3 April 2016 - Retrospectively registered.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/metabolismo , Exosomas/metabolismo , ARN Pequeño no Traducido/genética , Saliva/metabolismo , Terapia Combinada , Manejo de la Enfermedad , Neoplasias Esofágicas/etiología , Neoplasias Esofágicas/terapia , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Estudios Prospectivos , ARN Pequeño no Traducido/metabolismo , Sensibilidad y Especificidad
13.
Macromol Rapid Commun ; 43(7): e2100906, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35019170

RESUMEN

Polymeric materials implanted in the human body are usually invisible under X-ray, and the mixing of heavy metal salts into polymeric materials by physical compounding often poses compatibility problems. A new iodine-containing cyclic carbonate monomer, 4-iodo-N-(2-oxo-1,3-dioxan-5-yl)benzamide (IBTMC), is synthesized, which has a degradable carbonate group as its basic structural unit and iodine atoms attached to the side chain in the form of covalent bonds. The ring-opening polymerization of IBTMC is achieved at room temperature under the catalysis of the solid superbase 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD). The structure and X-ray developing ability of the synthesized polycarbonate are characterized by 1 H-NMR, X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), Gel Permeation Chromatography (GPC), and micro-computed tomography (Micro-CT). The iodine atoms remain bound to the polymer as covalent bonds after a series of reactions and exhibit a high level of X-ray opacity. In vitro degradation experiments of the polymer prove that the polymer is degradable.


Asunto(s)
Carbonatos , Cemento de Policarboxilato , Humanos , Cemento de Policarboxilato/química , Polimerizacion , Microtomografía por Rayos X
14.
Parasitol Res ; 121(9): 2601-2613, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35788769

RESUMEN

The aim of this study was to identify the aggregation sites and transmission characteristics of Gasterophilus pecorum, the dominant pathogen of endangered equines in desert steppe. Therefore, we tested with a four-arm olfactometer the olfactory response of the G. pecorum adults to the odors that have a great impact on their life cycle, and also investigated the occurrence sites of the adults in the area where the Przewalski's horse (Equus przewalskii) roam frequently during the peak period of G. pecorum infection. The results of four-directional olfactory test showed that the fresh horse feces had a stronger attraction rate on both male (50.4%) and female flies (38.2%). Stipa caucasica, the only oviposition plant where G. pecorum lay eggs, had a better attraction effect on females than that on males. And the attraction rates of S. caucasica to G. pecorum females in the early growth stage (Stipa I) and mid-growth stage (Stipa II) were 32.8% and 36.8%, respectively. In addition, the two-directional olfactory test showed that the attraction rate of males to fresh horse feces (68.90%) was higher than that to Stipa II (31.10%), and females also showed similar olfactory responses. Moreover, in our field investigation, 68.29% of G. pecorum adults were collected from around the horse feces. The results of laboratory test and field investigation implied that the location mechanism of G. pecorum aggregation for mating is related to the orientation of horse feces. The horse feces and the vicinity are the key contamination areas of G. pecorum, and it is also the areas where horses are seriously infected with G. pecorum. Those fresh feces, which gather abundant information about the host, naturally had the greatest chance of contacting with the host; G. pecorum adults create the opportunity to enter directly into the host's mouth and infect the host by laying eggs on S. caucasica, which is the most favorite plant of the host in this area. These characteristics are one of the main reasons why G. pecorum has become the dominant species under the condition of sparse vegetation in desert steppe.


Asunto(s)
Dípteros/fisiología , Heces/química , Enfermedades de los Caballos/parasitología , Enfermedades de los Caballos/transmisión , Parasitosis Intestinales/transmisión , Animales , Clima Desértico , Especies en Peligro de Extinción , Heces/parasitología , Femenino , Caballos , Parasitosis Intestinales/parasitología , Masculino , Parásitos/crecimiento & desarrollo , Parásitos/aislamiento & purificación , Desarrollo de la Planta , Plantas
15.
Am J Orthod Dentofacial Orthop ; 162(2): 182-192, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35248418

RESUMEN

INTRODUCTION: Chemokines play pivotal roles in orthodontic tooth movement (OTM) through osteoclast-mediated bone resorption, but the underlying mechanism remains unclear. We aimed to elucidate the effects of serial local vs systemic administration of the chemokine receptor CXCR4 antagonist AMD3100 on OTM. METHODS: The maxillary first molar (M1) of rats was moved mesially using a 10 g of force nickel-titanium coil spring. The injections were performed every other day with phosphate-buffered saline as a control, whereas local and systemic animals were injected with AMD3100 at the buccal palatal mucosa adjacent to M1 and subcutaneously, respectively. OTM distance and alveolar bone were examined by microcomputed tomography and histologic analysis. Osteoclast numbers were quantified using TRAP staining. Cathepsin K and stromal cell-derived factor-1 (SDF-1) were evaluated using immunohistochemistry. Reverse transcriptase polymerase chain reaction for cathepsin K, Runx2, SDF-1, CXCR4, RANKL, and OPG were also examined. RESULTS: OTM and osteoclast numbers were significantly decreased in the local and systemic groups compared with the control group, whereas there was no significant difference among the experimental groups. Local administration inhibited molar but not incisor movement. Trabecular thickness and trabecular spacing of the alveolar bone significantly increased, and trabecular number significantly decreased in the systemic group compared with the control group, whereas local injection also affected bone quality in the same tendency as a systemic injection. AMD3100 significantly downregulated the mRNA expression levels of cathepsin K, Runx2, SDF-1, RANKL, and RANKL/OPG ratio in both experimental groups. CONCLUSIONS: Local administration of AMD3100 can control initial OTM and diminish bone resorption processes during OTM via inhibition of the SDF-1/CXCR4 axis, similar to the systemic administration.


Asunto(s)
Resorción Ósea , Técnicas de Movimiento Dental , Animales , Bencilaminas , Catepsina K/farmacología , Subunidad alfa 1 del Factor de Unión al Sitio Principal , Ciclamas , Osteoclastos , Ratas , Receptores CXCR4 , Técnicas de Movimiento Dental/métodos , Microtomografía por Rayos X
16.
Chin J Traumatol ; 25(1): 49-53, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34518064

RESUMEN

PURPOSE: The main aim is to provide clinical reference for the application of mini suture anchor in the reduction and fixation of displaced temporomandibular joint (TMJ) disc with intracapsular condylar fracture. METHODS: From October 2018 to October 2019, 21 patients (31 sides) with intracapsular condylar fractures and articular disc displacement from West China Hospital of Stomatology, Sichuan University were included. The selection criteria were: (1) mandibular condylar fractures accompanied by displacement of the TMJ disc, confirmed by clinical examination, CT scan and other auxiliary examinations; (2) indication for surgical treatment; (3) no surgical contraindications; (4) no previous history of surgery in the operative area; (5) no facial nerve injury before the surgery; (6) informed consent to participate in the research program and (7) complete data. Patients without surgical treatment were excluded. The employed patients were followed up at 1, 3, 6 and 12 months after operation. Outcomes were assessed by success rate of operation, TMJ function and radiological examination results at 3 months after operation. Data were expressed as number and percent and analyzed using SPSS 19.0. RESULTS: All the surgical procedures were completed successfully and all the articular discs were firmly attached to the condyles. The articular disc sufficiently covered the condylar head after the fixation. The fixation remained stable when the mandible was moved in each direction by the surgeons. No complications occurred. The functions of the TMJ were well-recovered postoperatively in most cases. CT scan revealed that the screws were completely embedded in the bone without loosening or displacement. CONCLUSION: Mini suture anchor can provide satisfactory stabilization for the reduced articular disc and also promote the recovery of TMJ functions.


Asunto(s)
Luxaciones Articulares , Fracturas Mandibulares , Humanos , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/cirugía , Mandíbula , Cóndilo Mandibular , Fracturas Mandibulares/diagnóstico por imagen , Fracturas Mandibulares/cirugía , Anclas para Sutura , Disco de la Articulación Temporomandibular/diagnóstico por imagen , Disco de la Articulación Temporomandibular/cirugía
17.
Chin J Traumatol ; 25(3): 151-155, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35034763

RESUMEN

PURPOSE: The aim of this study is to evaluate the application value of virtual surgical planning in the management of mandibular condylar fractures and to provide a reliable reference. METHODS: This was a prospective randomized controlled study and recruited 50 patients requiring surgical treatment for their mandibular condylar fractures. The inclusion criteria were patients (1) diagnosed with a condylar fracture by two clinically experienced doctors and required surgical treatment; (2) have given consent for the surgical treatment; and (3) had no contraindications to the surgery. Patients were excluded from this study if: (1) they were diagnosed with a non-dislocated or only slightly dislocated condylar fracture; (2) the comminuted condylar fracture was too severe to be treated with internal reduction and fixation; or (3) patients could not complete follow-up for 3 months. There were 33 male and 17 female patients with 33 unilateral condylar fractures and 17 bilateral condylar fractures included. The 50 patients were randomly (random number) divided into control group (25 patients with 35 sides of condylar fractures) and experimental group (25 patients with 32 sides of condylar fractures). Virtual surgical planning was used in the experimental group, but only clinical experience was used in the control group. The patients were followed up for 1, 3, 6 and 12 months after operation. Variables including the rate of perfect reduction by radiological analysis, the average distance of deviation between preoperative and postoperative CT measurements using Geomagic software and postoperative clinical examinations (e.g., mouth opening, occlusion) were investigated for outcome measurement. SPSS 19 was adopted for data analysis. RESULTS: The average operation time was 180.60 min in the experimental group and 223.2 min in the control group. One week postoperatively, CT images showed that the anatomic reduction rate was 90.63% (29/32) in the experimental group and 68.57% (24/35) in the control group, revealing significant difference (X2 = 4.919, p = 0.027). Geomagic comparative analysis revealed that the average distance of deviation was also much smaller in the experimental group than that in the control group (0.639 mm vs. 0.995 mm; t = 3.824, p < 0.001). CONCLUSION: These findings suggest that virtual surgical planning can assist surgeons in surgical procedures, reduce operative time, and improve the anatomic reduction rate & accuracy, and thus of value in the diagnosis and treatment of condylar fractures.


Asunto(s)
Fracturas Conminutas , Fracturas Mandibulares , Femenino , Fijación Interna de Fracturas/métodos , Humanos , Masculino , Cóndilo Mandibular/diagnóstico por imagen , Cóndilo Mandibular/cirugía , Fracturas Mandibulares/diagnóstico por imagen , Fracturas Mandibulares/cirugía , Estudios Prospectivos , Resultado del Tratamiento
18.
Small ; 17(23): e2100501, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33896106

RESUMEN

Exploration of facile strategies for precise regulation of target gene expression remains highly challenging in the development of gene therapies. Especially, a stimuli-responsive nanocarrier integrated with ability of noninvasive remote control for treating wide types of cancers is rarely developed. Herein, a NIR-II absorbing semiconducting polymer (PBDTQ) is employed to remotely activate the heat-inducible heat-shock protein 70 (HSP70) promoter under laser irradiation, further realizing regulation of gene-directed enzyme prodrug therapy (GDEPT) for cancer treatment in mild hyperthermia. In this multifunctional nanocomposite, the PBDTQ and double suicide gene plasmid (pSG) based on HSP70 promoter are incorporated into a lipid complex. Upon NIR-II laser excitation, the mild photothermal effect (≈43 °C) generated from PBDTQ can cause the release of pSG and activation of HSP70 promoter, and then upregulate suicide gene expression triggered by the HSP70 promoter which can further convert the nontoxic prodrug into its cytotoxic metabolites. Therefore, this work demonstrates a universal NIR-II laser-triggered GDEPT using semiconducting polymers as the photothermal generator for cancer treatment with minimized collateral damage and nontargeted side effects.


Asunto(s)
Hipertermia Inducida , Nanopartículas , Neoplasias , Profármacos , Humanos , Rayos Infrarrojos , Neoplasias/tratamiento farmacológico , Fototerapia , Polímeros , Semiconductores
19.
Biomacromolecules ; 22(6): 2684-2692, 2021 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-34010561

RESUMEN

Nanocellulose has been studied extensively in polymer composites as it can be employed as biobased reinforcement for synthetic polymers. However, the challenge to optimize the reinforcing component to consume applied energy as much as possible remains. This is related to the reacting force in the test sample and its extensibility. Prolonging the fracture strain of the material is one of the most effective strategies for such a purpose. The investigation on nanocellulose movement in a polymer matrix could shed light on the nanocellulose reinforcing mechanism's fundamental understanding. In this work, a continuous nanocellulose network was used to prepare nanocellulose/polymer composites. Different from using noncontinuous nanofillers, e.g., cellulose nanofibers and nanocrystal, the regenerated cellulose gel network used in this work could move together with the polymer under an axial signal force, serving as an excellent model advantageous in investigating the movement of nanocellulose in the polymer matrix. The deformation of the nanocellulose in the matrix was able to be evaluated by tracking the fracture strain of the materials. A series of chemical cross-linked nanoporous cellulose hydrogels (CCNCGs) were prepared, and their fracture strain increased first and then decreased as the molar ratio of epichlorohydrin (ECH) to the anhydroglucose unit (AGU) of cellulose increased. Two polymer matrices, polycaprolactone (PCL) and polyurethane (PU), were selected to be polymerized in CCNCGs in situ. The fracture strain of CCNCG/PCL and CCNCG/PU nanocomposites in the tensile test showed the same tendency as neat CCNCGs in the hydrated state, regardless of the surrounding environment. The relatively independent motion of the nanocellulose network in the polymer matrix was clearly demonstrated. Possible mechanisms of the nanocellulose's independent motion in the polymer matrix were discussed, implying the potential of independent deformation of the continuous nanocellulose network in the polymer matrix.


Asunto(s)
Nanocompuestos , Nanofibras , Nanopartículas , Polímeros , Poliuretanos
20.
Biomacromolecules ; 22(10): 4037-4059, 2021 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-34506126

RESUMEN

The production of cellulose nanofibrils (CNFs) continues to receive considerable attention because of their desirable material characteristics for a variety of consumer applications. There are, however, challenges that remain in transitioning CNFs from research to widespread adoption in the industrial sectors, including production cost and material performance. This Review covers CNFs produced from nonconventional fibrillation methods as a potential alternative solution. Pretreating biomass by biological, chemical, mechanical, or physical means can render plant feedstocks more facile for processing and thus lower energy requirements to produce CNFs. CNFs from nonconventional fibrillation methods have been investigated for various applications, including films, composites, aerogels, and Pickering emulsifiers. Continued research is needed to develop protocols to standardize the characterization (e.g., degree of fibrillation) of the lignocellulosic fibrillation processes and resulting CNF products to make them more attractive to the industry for specific product applications.


Asunto(s)
Celulosa , Nanofibras
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