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1.
Nature ; 627(8003): 347-357, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38374256

RESUMEN

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% not of European ancestry), including 428,452 cases of T2D. We identify 1,289 independent association signals at genome-wide significance (P < 5 × 10-8) that map to 611 loci, of which 145 loci are, to our knowledge, previously unreported. We define eight non-overlapping clusters of T2D signals that are characterized by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type-specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial cells and enteroendocrine cells. We build cluster-specific partitioned polygenic scores5 in a further 279,552 individuals of diverse ancestry, including 30,288 cases of T2D, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned polygenic scores are associated with coronary artery disease, peripheral artery disease and end-stage diabetic nephropathy across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings show the value of integrating multi-ancestry genome-wide association study data with single-cell epigenomics to disentangle the aetiological heterogeneity that drives the development and progression of T2D. This might offer a route to optimize global access to genetically informed diabetes care.


Asunto(s)
Diabetes Mellitus Tipo 2 , Progresión de la Enfermedad , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Adipocitos/metabolismo , Cromatina/genética , Cromatina/metabolismo , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/genética , Diabetes Mellitus Tipo 2/clasificación , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patología , Diabetes Mellitus Tipo 2/fisiopatología , Nefropatías Diabéticas/complicaciones , Nefropatías Diabéticas/genética , Células Endoteliales/metabolismo , Células Enteroendocrinas , Epigenómica , Predisposición Genética a la Enfermedad/genética , Islotes Pancreáticos/metabolismo , Herencia Multifactorial/genética , Enfermedad Arterial Periférica/complicaciones , Enfermedad Arterial Periférica/genética , Análisis de la Célula Individual
2.
N Engl J Med ; 390(5): 397-408, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38294972

RESUMEN

BACKGROUND: Butantan-Dengue Vaccine (Butantan-DV) is an investigational, single-dose, live, attenuated, tetravalent vaccine against dengue disease, but data on its overall efficacy are needed. METHODS: In an ongoing phase 3, double-blind trial in Brazil, we randomly assigned participants to receive Butantan-DV or placebo, with stratification according to age (2 to 6 years, 7 to 17 years, and 18 to 59 years); 5 years of follow-up is planned. The objectives of the trial were to evaluate overall vaccine efficacy against symptomatic, virologically confirmed dengue of any serotype occurring more than 28 days after vaccination (the primary efficacy end point), regardless of serostatus at baseline, and to describe safety up to day 21 (the primary safety end point). Here, vaccine efficacy was assessed on the basis of 2 years of follow-up for each participant, and safety as solicited vaccine-related adverse events reported up to day 21 after injection. Key secondary objectives were to assess vaccine efficacy among participants according to dengue serostatus at baseline and according to the dengue viral serotype; efficacy according to age was also assessed. RESULTS: Over a 3-year enrollment period, 16,235 participants received either Butantan-DV (10,259 participants) or placebo (5976 participants). The overall 2-year vaccine efficacy was 79.6% (95% confidence interval [CI], 70.0 to 86.3) - 73.6% (95% CI, 57.6 to 83.7) among participants with no evidence of previous dengue exposure and 89.2% (95% CI, 77.6 to 95.6) among those with a history of exposure. Vaccine efficacy was 80.1% (95% CI, 66.0 to 88.4) among participants 2 to 6 years of age, 77.8% (95% CI, 55.6 to 89.6) among those 7 to 17 years of age, and 90.0% (95% CI, 68.2 to 97.5) among those 18 to 59 years of age. Efficacy against DENV-1 was 89.5% (95% CI, 78.7 to 95.0) and against DENV-2 was 69.6% (95% CI, 50.8 to 81.5). DENV-3 and DENV-4 were not detected during the follow-up period. Solicited systemic vaccine- or placebo-related adverse events within 21 days after injection were more common with Butantan-DV than with placebo (58.3% of participants, vs. 45.6%). CONCLUSIONS: A single dose of Butantan-DV prevented symptomatic DENV-1 and DENV-2, regardless of dengue serostatus at baseline, through 2 years of follow-up. (Funded by Instituto Butantan and others; DEN-03-IB ClinicalTrials.gov number, NCT02406729, and WHO ICTRP number, U1111-1168-8679.).


Asunto(s)
Vacunas contra el Dengue , Virus del Dengue , Dengue , Vacunas Atenuadas , Adulto , Niño , Preescolar , Humanos , Anticuerpos Antivirales , Dengue/prevención & control , Vacunas contra el Dengue/efectos adversos , Vacunas contra el Dengue/uso terapéutico , Virus del Dengue/inmunología , Método Doble Ciego , Vacunación , Vacunas , Vacunas Atenuadas/efectos adversos , Vacunas Atenuadas/uso terapéutico , Brasil , Eficacia de las Vacunas , Adolescente , Adulto Joven , Persona de Mediana Edad , Estudios de Seguimiento
3.
Polymers (Basel) ; 15(22)2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-38006088

RESUMEN

Iodine is commonly used as a dichroic material in polarizing films, while dichroic dyes are employed when high heat resistance is necessary. Direct dyes, which can be applied to poly(vinyl alcohol) (PVA) in an acidic environment, are the most popular; however, their hydrogen bonding interaction with the PVA chain can weaken in high-humidity conditions, leading to a potential change in color value or polarization property. Reactive dyes offer a promising alternative for use in high-humidity environments. In this study, five novel reactive dyes were synthesized and used to prepare dye-based polarizing films. The dichroic ratios, order parameters, and transition moments of the reactive dyes were calculated and compared to those of corresponding direct dyes. Molecular orbital calculations indicated minimal effects on the optical anisotropy of the polarizing films due to the transition moments of the reactive dyes remaining close to their molecular axes. As a result, the dichroic ratios of the polarizing films were mainly dependent on the orientation of the dyes towards their stretching direction, and showed a similar behavior compared to direct dyes. Under high-temperature and high-humidity conditions, the polarizing film using reactive dyes showed superior durability compared to the direct dye-based film.

4.
Hepatology ; 78(6): 1843-1857, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37222264

RESUMEN

BACKGROUND AND AIMS: There is great interest in identifying microbiome features as reliable noninvasive diagnostic and/or prognostic biomarkers for non-cirrhotic NASH fibrosis. Several cross-sectional studies have reported gut microbiome features associated with advanced NASH fibrosis and cirrhosis, where the most prominent features are associated with cirrhosis. However, no large, prospectively collected data exist establishing microbiome features that discern non-cirrhotic NASH fibrosis, integrate the fecal metabolome as disease biomarkers, and are unconfounded by BMI and age. APPROACH AND RESULTS: Results from shotgun metagenomic sequencing performed on fecal samples prospectively collected from 279 US patients with biopsy-proven NASH (F1-F3 fibrosis) enrolled in the REGENERATE I303 study were compared to those from 3 healthy control cohorts and integrated with the absolute quantification of fecal bile acids. Microbiota beta-diversity was different, and BMI- and age-adjusted logistic regression identified 12 NASH-associated species. Random forest prediction models resulted in an AUC of 0.75-0.81 in a receiver operator characteristic analysis. In addition, specific fecal bile acids were significantly lower in NASH and correlated with plasma C4 levels. Microbial gene abundance analysis revealed 127 genes increased in controls, many involving protein synthesis, whereas 362 genes were increased in NASH many involving bacterial environmental responses (false discovery rate < 0.01). Finally, we provide evidence that fecal bile acid levels may be a better discriminator of non-cirrhotic NASH versus health than either plasma bile acids or gut microbiome features. CONCLUSIONS: These results may have value as a set of baseline characteristics of non-cirrhotic NASH against which therapeutic interventions to prevent cirrhosis can be compared and microbiome-based diagnostic biomarkers identified.


Asunto(s)
Microbioma Gastrointestinal , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Estudios Transversales , Cirrosis Hepática/complicaciones , Fibrosis , Ácidos y Sales Biliares , Heces/microbiología , Biomarcadores
5.
Int J Mol Sci ; 24(9)2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37175567

RESUMEN

Titanium dioxide (TiO2) plays a pivotal role in photocatalytic reactions and holds great promise for the cosmetic and paint industries due to its white color and high refractive index. However, the original color of TiO2 changes gradually to blue or yellow with UV irradiation, which affects its color realization. We encapsulated TiO2 with several natural organic dye compounds, including purpurin, curcumin, and safflower, to control its photochromism and realize a range of different colors. The chemical reaction between TiO2 and dyes based on their functional group was investigated, and the light absorption was tested via FTIR and UV-Vis spectroscopy. The changes in morphology and size distribution additionally supported their successful encapsulation. The discoloration after UV irradiation was evaluated by measuring the color difference (ΔE) of control TiO2 and dye encapsulated TiO2. The unique structure utilized natural dyes to preserve photochromism based on the physical barrier and automatically controlled the electronic transition of core TiO2. In particular, the color difference values of purpurin and curcumin were 4.05 and 3.76, which is lower than the 5.36 of the control TiO2. Dye encapsulated TiO2 was manipulated into lipstick to verify its color realization and retention.


Asunto(s)
Curcumina , Rayos Ultravioleta , Titanio/química , Colorantes/química , Catálisis
6.
medRxiv ; 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37034649

RESUMEN

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes. To characterise the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study (GWAS) data from 2,535,601 individuals (39.7% non-European ancestry), including 428,452 T2D cases. We identify 1,289 independent association signals at genome-wide significance (P<5×10-8) that map to 611 loci, of which 145 loci are previously unreported. We define eight non-overlapping clusters of T2D signals characterised by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial, and enteroendocrine cells. We build cluster-specific partitioned genetic risk scores (GRS) in an additional 137,559 individuals of diverse ancestry, including 10,159 T2D cases, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned GRS are more strongly associated with coronary artery disease and end-stage diabetic nephropathy than an overall T2D GRS across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings demonstrate the value of integrating multi-ancestry GWAS with single-cell epigenomics to disentangle the aetiological heterogeneity driving the development and progression of T2D, which may offer a route to optimise global access to genetically-informed diabetes care.

7.
J Cyst Fibros ; 22(4): 636-643, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36822979

RESUMEN

BACKGROUND: The respiratory tract fungal microbiome in cystic fibrosis (CF) has been understudied despite increasing recognition of fungal pathogens in CF lung disease. We sought to better understand the fungal communities in adults with CF, and to define relationships between fungal profiles and clinical characteristics. METHODS: We enrolled 66 adults with CF and collected expectorated sputum, spirometry, Cystic Fibrosis Questionnaire-revised, and clinical data. Fungi were molecularly profiled by sequencing of the internal transcribed spacer (ITS) region. Total fungal abundance was measured by quantitative PCR. Relative abundance and qPCR-corrected abundances were determined. Selective fungus culture identified cultivable fungi. Alpha diversity and beta diversity were measured and relationships with clinical parameters were interrogated. RESULTS: Median age was 29 years and median FEV1 percent predicted 58%. Members of the Candida genus were the most frequent dominant taxa in CF sputum. Apiotrichum, Trichosporon, Saccharomyces cerevisiae, and Scedosporium were present in high relative abundance in few samples; whereas, Aspergillus species were detected at low levels. Higher FEV1% predicted and CFTR modulator use were associated with greater alpha-diversity. Chronic azithromycin use was associated with lower alpha-diversity. Patients with acute pulmonary had distinct fungal community composition compared to clinically stable subjects. Differing yeast species were mainly responsible for the community differences. CONCLUSION: The respiratory tract fungal microbiome in adults with CF is associated with lung function, pulmonary exacerbation status, macrolide use, and CFTR modulator use. Future work to better understand fungal diversity in the CF airway and its impact on lung health is necessary.


Asunto(s)
Fibrosis Quística , Micobioma , Humanos , Adulto , Hongos , Regulador de Conductancia de Transmembrana de Fibrosis Quística , Sistema Respiratorio/microbiología , Esputo/microbiología
8.
Gut Microbes ; 14(1): 2154091, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36474348

RESUMEN

Antibiotics are administered near-universally to very low birth weight (VLBW) infants after birth for suspected early-onset sepsis (EOS). We previously identified a phenotypic group of VLBW infants, referred to as low-risk for EOS (LRE), whose risk of EOS is low enough to avoid routine antibiotic initiation. In this cohort study, we compared 18 such infants with 30 infants categorized as non-LRE to determine if the lower risk of pathogen transmission at birth is accompanied by differences in microbiome acquisition and development. We did shotgun metagenomic sequencing of 361 fecal samples obtained serially. LRE infants had a higher human-to-bacterial DNA ratio than non-LRE infants in fecal samples on days 1-3 after birth, confirming lower bacterial acquisition among LRE infants. The microbial diversity and composition in samples from days 4-7 differed between the groups with a predominance of Staphylococcus epidermidis in LRE infants and Enterobacteriaceae sp. in non-LRE infants. Compositional differences were congruent with the distribution of virulence factors and antibiotic resistant genes. After the first week, the overall composition was similar, but changes in relative abundance for several taxa with increasing age differed between groups. Of the nine late-onset bacteremia episodes, eight occurred in non-LRE infants. Species isolated from the blood culture was detected in the pre-antibiotic fecal samples of the infant for all episodes, though these species were also found in infants without bacteremia. In conclusion, LRE infants present a distinct pattern of microbiome development that is aligned with their low risk for EOS. Further investigation to determine the impact of these differences on later outcomes such as late-onset bacteremia is warranted.


Asunto(s)
Microbioma Gastrointestinal , Recien Nacido Prematuro , Recién Nacido , Humanos , Estudios de Cohortes , Metagenómica , Antibacterianos/farmacología
9.
Foods ; 11(23)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36496685

RESUMEN

Pectins are plant polysaccharides consumed as part of a diet containing fruits and vegetables. Inside the gastrointestinal tract, pectin cannot be metabolized by the mammalian cells but is fermented by the gut microbiota in the colon with the subsequent release of end products including short-chain fatty acids (SCFA). The prebiotic effects of pectin have been previously evaluated but reports are inconsistent, most likely due to differences in the pectin chemical structure which can vary by molecular weight (MW) and degree of esterification (DE). Here, the effects of two different MW lemon pectins with varying DEs on the gut microbiota of two donors were evaluated in vitro. The results demonstrated that low MW, high DE lemon pectin (LMW-HDE) altered community structure in a donor-dependent manner, whereas high MW, low DE lemon pectin (HMW-LDE) increased taxa within Lachnospiraceae in both donors. LMW-HDE and HMW-LDE lemon pectins both increased total SCFAs (1.49- and 1.46-fold, respectively) and increased acetic acid by 1.64-fold. Additionally, LMW-HDE lemon pectin led to an average 1.41-fold increase in butanoic acid. Together, these data provide valuable information linking chemical structure of pectin to its effect on the gut microbiota structure and function, which is important to understanding its prebiotic potential.

10.
Dev Reprod ; 26(2): 79-90, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35950165

RESUMEN

Krüppel-like factor 10 (KLF10) regulates various cellular functions, such as proliferation, differentiation and apoptosis, as well as the homeostasis of several types of tissue. In the present study, we attempted a loss-of-function analysis of zebrafish Klf11a and Klf11b, which constitute human KLF10 homologs. Embryos injected with klf11b-morpholino (MO) showed developmental retardation and cell death, whereas klf11a-MO-injected embryos showed normal development. In klf11b-MO-injected embryos, a dramatic increase in the amount of zebrafish p53 mRNA might be the cause of the increase in that of bax. The degree of apoptosis decreased in the klf11b-MO and p53-MO co-injected embryos. These findings imply that KLF10 is a negative regulator of p53-dependent transcription, suggesting that the KLF10/p53 complex may play an important role in apoptosis for maintenance of tissue homeostasis during embryonic development.

11.
J Adv Prosthodont ; 14(3): 162-172, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35855317

RESUMEN

PURPOSE: The present study aims to analyze the effect of abutment neck taper and types of cement on the amount of undetected remnant cement of cement-retained implant prostheses. MATERIALS AND METHODS: Three neck taper angles (53°, 65°, 77°) and three types of cement (RMGI: resin-modified glass ionomer, ZPC: zinc phosphate cement, ZOE: zinc oxide eugenol cement) were used. For each group, the surface percentage was measured using digital image and graphic editing software. The weight of before and after removing remnant cement from the abutment-crown assembly was measured using an electronic scale. Two-way ANOVA and Duncan & Scheffe's test were used to compare the calculated surface percentage and weight of remnant cement (α = .05). RESULTS: There were significant differences in remnant cement surface percentage and weight according to neck taper angles (P < .05). However, there were no significant differences in remnant cement surface percentage and weight on types of cement. No interaction was found between neck taper angles and types of luting cement (P > .05). The wide abutment with a small neck taper angle showed the most significant amount of remnant cement. And the types of luting cement did not influence the amount of residual cement. CONCLUSION: To remove excess cement better, the emergence profile of the crown should be straight to the neck taper of the abutment in cement-retained implant restoration.

12.
Nat Genet ; 54(5): 560-572, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35551307

RESUMEN

We assembled an ancestrally diverse collection of genome-wide association studies (GWAS) of type 2 diabetes (T2D) in 180,834 affected individuals and 1,159,055 controls (48.9% non-European descent) through the Diabetes Meta-Analysis of Trans-Ethnic association studies (DIAMANTE) Consortium. Multi-ancestry GWAS meta-analysis identified 237 loci attaining stringent genome-wide significance (P < 5 × 10-9), which were delineated to 338 distinct association signals. Fine-mapping of these signals was enhanced by the increased sample size and expanded population diversity of the multi-ancestry meta-analysis, which localized 54.4% of T2D associations to a single variant with >50% posterior probability. This improved fine-mapping enabled systematic assessment of candidate causal genes and molecular mechanisms through which T2D associations are mediated, laying the foundations for functional investigations. Multi-ancestry genetic risk scores enhanced transferability of T2D prediction across diverse populations. Our study provides a step toward more effective clinical translation of T2D GWAS to improve global health for all, irrespective of genetic background.


Asunto(s)
Diabetes Mellitus Tipo 2 , Estudio de Asociación del Genoma Completo , Diabetes Mellitus Tipo 2/epidemiología , Etnicidad , Predisposición Genética a la Enfermedad , Humanos , Polimorfismo de Nucleótido Simple/genética , Factores de Riesgo
14.
J Prosthet Dent ; 2022 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-35570169

RESUMEN

Heat elicited during the osteotomy for implant placement may have a significant impact on the vitality of surrounding bone and on the healing capacity for osseointegration. This article describes a digital workflow for creating a coolant channel for the direct irrigation of the osteotomy site through an implant surgical guide. This technique can be particularly advantageous when the surgical guide restricts access for direct irrigation of the osteotomy site.

15.
Commun Biol ; 5(1): 329, 2022 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-35393509

RESUMEN

South Asians are at high risk of developing type 2 diabetes (T2D). We carried out a genome-wide association meta-analysis with South Asian T2D cases (n = 16,677) and controls (n = 33,856), followed by combined analyses with Europeans (neff = 231,420). We identify 21 novel genetic loci for significant association with T2D (P = 4.7 × 10-8 to 5.2 × 10-12), to the best of our knowledge at the point of analysis. The loci are enriched for regulatory features, including DNA methylation and gene expression in relevant tissues, and highlight CHMP4B, PDHB, LRIG1 and other genes linked to adiposity and glucose metabolism. A polygenic risk score based on South Asian-derived summary statistics shows ~4-fold higher risk for T2D between the top and bottom quartile. Our results provide further insights into the genetic mechanisms underlying T2D, and highlight the opportunities for discovery from joint analysis of data from across ancestral populations.


Asunto(s)
Diabetes Mellitus Tipo 2 , Estudio de Asociación del Genoma Completo , Pueblo Asiatico/genética , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/genética , Predisposición Genética a la Enfermedad , Humanos , Polimorfismo de Nucleótido Simple
16.
Pediatr Blood Cancer ; 69(1): e29384, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34709713

RESUMEN

BACKGROUND: The contribution of the gastrointestinal tract microbiome to outcomes after allogeneic hematopoietic cell transplantation (HCT) is increasingly recognized. Investigations of larger pediatric cohorts aimed at defining the microbiome state and associated metabolic patterns pretransplant are needed. METHODS: We sought to describe the pretransplant stool microbiome in pediatric allogenic HCT patients at four centers. We performed shotgun metagenomic sequencing and untargeted metabolic profiling on pretransplant stool samples. Samples were compared with normal age-matched controls and by clinical characteristics. We then explored associations between stool microbiome measurements and metabolite concentrations. RESULTS: We profiled stool samples from 88 pediatric allogeneic HCT patients, a median of 4 days before transplant. Pretransplant stool samples differed from healthy controls based on indices of alpha diversity and in the proportional abundance of specific taxa and bacterial genes. Relative to stool from healthy patients, samples from HCT patients had decreased proportion of Bacteroides, Ruminococcaeae, and genes involved in butyrate production, but were enriched for gammaproteobacterial species. No systematic differences in stool microbiome or metabolomic profiles by age, transplant indication, or hospital were noted. Stool metabolites demonstrated strong correlations with microbiome composition. DISCUSSION: Stool samples from pediatric allogeneic HCT patients demonstrate substantial dysbiosis early in the transplant course. As microbiome disruptions associate with adverse transplant outcomes, pediatric-specific analyses examining longitudinal microbiome and metabolome changes are imperative to identify causal associations and to inform rational design of interventions.


Asunto(s)
Microbioma Gastrointestinal , Trasplante de Células Madre Hematopoyéticas , Microbiota , Niño , Heces , Humanos , Metaboloma
17.
J Prosthet Dent ; 128(2): 206-210, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33608106

RESUMEN

STATEMENT OF PROBLEM: Cigarette smoke can cause discoloration of artificial denture teeth. However, studies on the effects of heated tobacco product smoke on artificial denture teeth are lacking. PURPOSE: The purpose of this in vitro study was to evaluate the effects of conventional cigarette and heated tobacco product smoke on the color stability of artificial denture teeth. MATERIAL AND METHODS: Ninety maxillary central incisor denture teeth (Endura Anterior HC5 A3; Shofu) were randomly divided into 3 groups (n=30). Teeth in the control group were exposed to air; those in group CC were exposed to conventional cigarette (Marlboro Medium; Philip Morris) smoke, and those in group HT were exposed to heated tobacco product (IQOS 2.4 plus holder, Marlboro Heets Silver; Philip Morris) smoke. Before the experiment, the shade of the artificial denture teeth was evaluated in accordance with the Commission International de I'Eclairage (CIELab) color system by using a spectrophotometer (Shadepilot; DeguDent GmbH). The average CIELab value was estimated by scanning the entire labial surface of each specimen. To simulate smoking, standard conditions described by the Coresta Recommended Method N°22 were used-the puff duration was 2 seconds, with a 60-second interval between puffs. For each cigarette, 6 puffs and 6 intervals were simulated across 372 seconds. A total of 105 cigarettes were used based on a smoking simulation of 15 cigarettes each day for 7 days. The teeth in the control group were stored in fresh air in the smoke chamber for the same period as those in the experimental groups. After the experiment, L∗, a∗, and b∗ values were measured, and ΔE was calculated to evaluate the color change. All statistical analyses were performed with a statistical software program using a paired t test to determine discoloration after exposure to cigarette smoke. One-way ANOVA and the Tukey test were used to evaluate the significant differences between groups (α=.05). RESULTS: Lightness was significantly lower in the CC and HT groups (P<.001). All CIELab values showed statistically significant differences in the CC group. The greatest color change was observed in the CC group (ΔE=6.93 ±0.59), whereas the HT group showed a clinically imperceptible color change (ΔE=0.79 ±0.21). Discoloration was minimal in the CC group (ΔE=0.34 ±0.13). CONCLUSIONS: Conventional cigarette and heated tobacco product smoke can change the color of denture teeth. Heated tobacco product smoke causes less discoloration of denture teeth.


Asunto(s)
Productos de Tabaco , Diente Artificial , Dentaduras , Fumar , Nicotiana
18.
JID Innov ; 1(4): 100051, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34909748

RESUMEN

A cross-sectional study of 41 children aged 4-17 years with alopecia areata and 41 of their siblings without alopecia areata was conducted. A total of 51% had the Severity of Alopecia Tool scores in the range of 0-25%, 12% had scores between 26% and 49%, and 36% had scores between 75% and 100%. The fecal microbiome was characterized using shotgun metagenomic sequencing. A comparison of alpha and beta diversity yielded a small but statistically significant difference on the basis of Jaccard distance, which measures species presence and absence between samples. However, a follow-up analysis did not reveal the particular species that were present more often in one group. The relative abundance of one species, Ruminococcus bicirculans, was decreased in patients with alopecia areata relative to that in their sibling controls. An analysis of gene ortholog abundance identified 20 orthologs that were different between groups, including spore germination genes and genes for metal transportation. The associations reported in this study support a view of pediatric alopecia areata as a systemic disease that has effects on hair but also leads to internal changes, including differences in the gut microbiome.

19.
Wound Repair Regen ; 29(5): 801-809, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33964094

RESUMEN

Leg ulcers are estimated to occur in 1%-10% of North American patients with sickle cell disease (SCD). Their pathophysiology remains poorly defined, but as with other chronic wounds, it is hypothesised that the microbial milieu, or microbiome, contributes to their healing and clinical outcomes. This study utilises 16S ribosomal RNA (rRNA) gene sequencing to describe, for the first time, the microbiome of the SCD leg ulcer and its association with clinical factors. In a cross-sectional analysis of 42 ulcers, we recovered microbial profiles similar to other chronic wounds in the predominance of anaerobic bacteria and opportunistic pathogens including Staphylococcus, Corynebacterium, and Finegoldia. Ulcers separated into two clusters: one defined by predominance of Staphylococcus and smaller surface area, and the other displaying a greater diversity of taxa and larger surface area. We also find that the relative abundance of Porphyromonas is negatively associated with haemoglobin levels, a key clinical severity indicator for SCD, and that Finegoldia relative abundance is negatively associated with CD19+ B cell count. Finally, ratios of Corynebacterium:Lactobacillus and Staphylococcus:Lactobacillus are elevated in the intact skin of individuals with a history of SCD leg ulcers, while the ratio of Lactobacillus:Bacillus is elevated in that of individuals without a history of ulcers. Investigations of the skin microbiome in relation to SCD ulcer pathophysiology can inform clinical guidelines for this poorly understood chronic wound, as well as enhance broader understanding about the role of the skin microbiome in delayed wound healing.


Asunto(s)
Anemia de Células Falciformes , Úlcera de la Pierna , Microbiota , Estudios Transversales , Humanos , Cicatrización de Heridas
20.
J Pain ; 22(11): 1530-1544, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34029686

RESUMEN

The present experiments determined the effects of the narrow-spectrum antibiotic vancomycin on inflammatory pain-stimulated and pain-depressed behaviors in rats. Persistent inflammatory pain was modeled using dilute formalin (0.5%). Two weeks of oral vancomycin administered in drinking water attenuated Phase II formalin pain-stimulated behavior, and prevented formalin pain-depressed wheel running. Fecal microbiota transplantation produced a non-significant trend toward reversal of the vancomycin effect on pain-stimulated behavior. Vancomycin depleted Firmicutes and Bacteroidetes populations in the gut while having a partial sparing effect on Lactobacillus species and Clostridiales. The vancomycin treatment effect was associated with an altered profile in amino acid concentrations in the gut with increases in arginine, glycine, alanine, proline, valine, leucine, and decreases in tyrosine and methionine. These results indicate that vancomycin may have therapeutic effects against persistent inflammatory pain conditions that are distal to the gut. PERSPECTIVE: The narrow-spectrum antibiotic vancomycin reduces pain-related behaviors in the formalin model of inflammatory pain. These data suggest that manipulation of the gut microbiome may be one method to attenuate inflammatory pain amplitude.


Asunto(s)
Aminoácidos/efectos de los fármacos , Antibacterianos/farmacología , Conducta Animal/efectos de los fármacos , Microbioma Gastrointestinal/efectos de los fármacos , Inflamación/tratamiento farmacológico , Actividad Motora/efectos de los fármacos , Dolor/tratamiento farmacológico , Vancomicina/farmacología , Animales , Modelos Animales de Enfermedad , Femenino , Inflamación/complicaciones , Dolor/etiología , Ratas Endogámicas F344
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