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2.
Nature ; 566(7742): 73-78, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30728521

RESUMEN

Retrotransposable elements are deleterious at many levels, and the failure of host surveillance systems for these elements can thus have negative consequences. However, the contribution of retrotransposon activity to ageing and age-associated diseases is not known. Here we show that during cellular senescence, L1 (also known as LINE-1) retrotransposable elements become transcriptionally derepressed and activate a type-I interferon (IFN-I) response. The IFN-I response is a phenotype of late senescence and contributes to the maintenance of the senescence-associated secretory phenotype. The IFN-I response is triggered by cytoplasmic L1 cDNA, and is antagonized by inhibitors of the L1 reverse transcriptase. Treatment of aged mice with the nucleoside reverse transcriptase inhibitor lamivudine downregulated IFN-I activation and age-associated inflammation (inflammaging) in several tissues. We propose that the activation of retrotransposons is an important component of sterile inflammation that is a hallmark of ageing, and that L1 reverse transcriptase is a relevant target for the treatment of age-associated disorders.


Asunto(s)
Senescencia Celular/genética , Inflamación/genética , Interferón Tipo I/metabolismo , Elementos de Nucleótido Esparcido Largo/genética , Envejecimiento/genética , Envejecimiento/patología , Animales , Regulación hacia Abajo , Femenino , Fibroblastos/metabolismo , Fibroblastos/patología , Humanos , Inflamación/patología , Lamivudine/farmacología , Masculino , Ratones , Fenotipo , ADN Polimerasa Dirigida por ARN/genética , ADN Polimerasa Dirigida por ARN/metabolismo , Inhibidores de la Transcriptasa Inversa/farmacología
3.
BMC Oral Health ; 24(1): 959, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39153971

RESUMEN

BACKGROUND: Enamel is highly transparent at short wavelength infrared imaging (SWIR) wavelengths allowing the detection of dental decay without the need for ionizing radiation. The purpose of this study was to use SWIR imaging methods including cross polarization optical coherence tomography (CP-OCT), occlusal transillumination (SWIR-OT), proximal transillumination (SWIR-PT), and occlusal reflectance (SWIR-R) to image interproximal lesions in vivo and compare the sensitivity with radiography. METHODS: Participants (n = 30) aged 18-80 each with a radiopositive interproximal lesion scheduled for restoration were enrolled in the study. Studies have shown that the opposing proximal surfaces across the contact will likely also have lesions. SWIR images were acquired of the adjoining teeth at each contact with an interproximal lesion scheduled for restoration. Lesion presence and depth were assessed on each side of the contact for radiography and each SWIR imaging method. Lesions on radiographs and in CP-OCT images were identified by a single examiner while lesions in SWIR images were identified by a contrast threshold via semi-automatic image segmentation. RESULTS: All SWIR imaging methods had significantly higher sensitivity (P < 0.05) than radiographs for the detection of interproximal lesions on the teeth opposite those restored. CP-OCT and SWIR-R imaging methods had significantly higher sensitivity than the other methods. SWIR imaging methods showed significantly higher lesion contrast than radiography. CONCLUSIONS: SWIR imaging methods can be used to detect interproximal lesions on posterior teeth with higher diagnostic performance than radiographs. CP-OCT appears well suited as a potential gold standard for the detection of interproximal lesions and assessment of their severity in vivo.


Asunto(s)
Caries Dental , Tomografía de Coherencia Óptica , Transiluminación , Humanos , Tomografía de Coherencia Óptica/métodos , Persona de Mediana Edad , Anciano , Adolescente , Anciano de 80 o más Años , Adulto , Caries Dental/diagnóstico por imagen , Caries Dental/patología , Adulto Joven , Transiluminación/métodos , Rayos Infrarrojos , Femenino , Masculino , Esmalte Dental/diagnóstico por imagen , Esmalte Dental/patología , Sensibilidad y Especificidad , Procesamiento de Imagen Asistido por Computador/métodos
4.
Psychogeriatrics ; 24(2): 249-258, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38155441

RESUMEN

BACKGROUND: The increasing needs of people living with dementia (PLWD) in Vietnam present an enormous public health challenge. Vietnam is an understudied country, and little is known regarding the overall unmet needs of caregivers or the demographic risk factors associated with unmet caregiving needs. This study aimed to determine the burden of unmet care needs of community-dwelling PLWD and identify sociodemographic risks associated with unmet care needs. METHODS: A cross-sectional study in a rural area facing urbanisation in Hanoi, Vietnam recruited PWLD-caregiver dyads with multistage sampling. We utilised the Camberwell Assessment of Need for the Elderly (CANE) instrument to evaluate care needs across four domains. Caregivers rated PLWD needs, with higher scores indicating greater unmet needs. The Mann-Whitney test was employed for comparing two groups, while the Kruskal-Wallis test was used for comparisons involving more than two groups in the analysis, and a P-value of less than 0.05 was considered statistically significant. RESULTS: Among 90 PLWD participating in the study, the overall mean care needs score was 11.6 ± 4.3, with only 16.2% of PLWD having their care needs met. Environmental and physical needs were more frequently met than psychological or social needs. Only 48.0% and 43.9% of environmental and physical needs were met respectively, and a meagre 20.9% and 23.6% for psychological and social needs. Unmet care needs were more frequent for PWLD who were female, single or divorced, had lower monthly household income, or who were in more advanced stages of dementia, as indicated by Clinical Dementia Rating scores ≥1. CONCLUSIONS: Unmet needs for PWLD are common. Increased caregiver education, resources, and services in Vietnam are urgently required to improve the quality of life for this population.


Asunto(s)
Demencia , Calidad de Vida , Anciano , Humanos , Femenino , Masculino , Estudios Transversales , Evaluación de Necesidades , Vietnam/epidemiología , Demencia/epidemiología
5.
AIDS Care ; 35(12): 1928-1937, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-36794343

RESUMEN

Disclosure of HIV status is an important part of pediatric care. We studied disclosure and clinical outcomes in a multi-country Asian cohort of children and adolescents with HIV. Those 6-19 years of age who initiated combination antiretroviral therapy (cART) between 2008 and 2018, and who had at least one follow-up clinic visit were included. Data up to December 2019 were analyzed. Cox and competing risk regression analyses were used to assess the effect of disclosure on disease progression (WHO clinical stage 3 or 4), loss to follow-up (LTFU; > 12 months), and death. Of 1913 children and adolescents (48% female; median [IQR] age 11.5 [9.2-14.7] years at last clinic visit), 795 (42%) were disclosed to about their HIV status at a median age of 12.9 years (IQR: 11.8-14.1). During follow-up, 207 (11%) experienced disease progression, 75 (3.9%) were LTFU, and 59 (3.1%) died. There were lower hazards of disease progression (adjusted hazard ratio [aHR] 0.43 [0.28-0.66]) and death (aHR 0.36 [0.17-0.79]) for those disclosed to compared with those who were not. Disclosure and its appropriate implementation should be promoted in pediatric HIV clinics in resource-limited settings.


Asunto(s)
Revelación , Infecciones por VIH , Humanos , Niño , Femenino , Adolescente , Masculino , Infecciones por VIH/tratamiento farmacológico , Estudios Retrospectivos , Asia/epidemiología , Perdida de Seguimiento , Progresión de la Enfermedad
6.
BMC Pregnancy Childbirth ; 23(1): 788, 2023 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-37951881

RESUMEN

BACKGROUND: Pregnancy has major effects that make hematology parameters outside of normal reference ranges. Therefore, we conducted this study to establish reference intervals for Vietnamese pregnant women. METHODS: From June 2023 to Augst 2023, blood samples from 879 eligible pregnant women were run on DxH 900 hematology analyzer and ACL TOP 550 coagulation analyzer. The tested parameters are prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), white blood cell (WBC) and its differentials (neutrophils, lymphocytes, monocytes, eosinophils and basophils), red blood cell (RBC), hemoglobin (HGB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), RBC distribution width (RDW), RBC distribution width standard deviation (RDW-SD), platelet count (PLT), mean platelet volume (MPV). A non-parametric method was used to establish the 2.5th and 97.5th percentile reference intervals. RESULTS: PT, APTT decrease but fibrinogen increases during pregnancy. Physiological adaptations of pregnancy result in a decrease in RBC count, but an increase in WBC count and no changes in platelet count. The reference intervals for PT (seconds), APTT (seconds), fibrinogen (mg/dL), in the first trimester were 10.30-12.88, 25.40-35.46, 280.28-559.00, in the second trimester were 9.80-11.66, 24.05-33.23, 347.75-593.35, in the third trimester were 9.60-11.40, 23.40-31.80, 330.28-628.56, respectively. The reference intervals for main hematology parameters which are WBC (× 109/L), RBC (× 1012/L), HGB (g/dL), HCT (%), PLT (× 109/L) in the first trimester were 6.33-15.24, 3.73-5.32, 10.33-13.95, 32.22-42.29, 169.66-413.88, in the second trimester were 6.99-15.55, 3.33-4.98, 9.71-13.17, 30.26-40.07, 172.34-372.19, in the third trimester were 6.22-14.14, 3.54-4.98, 9.80-13.97, 31.11-42.70, 151.30-417.14, respectively. CONCLUSIONS: Most established referenced intervals from each trimester differ from other trimesters. These trimester-specific reference ranges for Vietnamese pregnant women will aid clinicians in entepreting parameters and help other laboratories adopt these ranges after validating. TRIAL REGISTRATION: This study is registered at www. CLINICALTRIALS: gov as NCT05929326.


Asunto(s)
Mujeres Embarazadas , Pueblos del Sudeste Asiático , Femenino , Embarazo , Humanos , Recuento de Células Sanguíneas , Pruebas de Coagulación Sanguínea , Hemoglobinas/análisis , Fibrinógeno , Valores de Referencia
7.
N Engl J Med ; 381(14): 1347-1357, 2019 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-31577876

RESUMEN

BACKGROUND: The World Health Organization has set ambitious targets for the global elimination of tuberculosis. However, these targets will not be achieved at the current rate of progress. METHODS: We performed a cluster-randomized, controlled trial in Ca Mau Province, Vietnam, to evaluate the effectiveness of active community-wide screening, as compared with standard passive case detection alone, for reducing the prevalence of tuberculosis. Persons 15 years of age or older who resided in 60 intervention clusters (subcommunes) were screened for pulmonary tuberculosis, regardless of symptoms, annually for 3 years, beginning in 2014, by means of rapid nucleic acid amplification testing of spontaneously expectorated sputum samples. Active screening was not performed in the 60 control clusters in the first 3 years. The primary outcome, measured in the fourth year, was the prevalence of microbiologically confirmed pulmonary tuberculosis among persons 15 years of age or older. The secondary outcome was the prevalence of tuberculosis infection, as assessed by an interferon gamma release assay in the fourth year, among children born in 2012. RESULTS: In the fourth-year prevalence survey, we tested 42,150 participants in the intervention group and 41,680 participants in the control group. A total of 53 participants in the intervention group (126 per 100,000 population) and 94 participants in the control group (226 per 100,000) had pulmonary tuberculosis, as confirmed by a positive nucleic acid amplification test for Mycobacterium tuberculosis (prevalence ratio, 0.56; 95% confidence interval [CI], 0.40 to 0.78; P<0.001). The prevalence of tuberculosis infection in children born in 2012 was 3.3% in the intervention group and 2.6% in the control group (prevalence ratio, 1.29; 95% CI, 0.70 to 2.36; P = 0.42). CONCLUSIONS: Three years of community-wide screening in persons 15 years of age or older who resided in Ca Mau Province, Vietnam, resulted in a lower prevalence of pulmonary tuberculosis in the fourth year than standard passive case detection alone. (Funded by the Australian National Health and Medical Research Council; ACT3 Australian New Zealand Clinical Trials Registry number, ACTRN12614000372684.).


Asunto(s)
Enfermedades Endémicas/prevención & control , Tamizaje Masivo/métodos , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis Pulmonar/diagnóstico , Adolescente , Adulto , Niño , Servicios de Salud Comunitaria , Femenino , Humanos , Análisis de Intención de Tratar , Masculino , Mycobacterium tuberculosis/genética , Técnicas de Amplificación de Ácido Nucleico , Prevalencia , Esputo/microbiología , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/prevención & control , Vietnam/epidemiología , Adulto Joven
8.
Appl Opt ; 59(19): 5845-5850, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32609712

RESUMEN

The transparent-conducting performance is estimated through figure-of-merit (FOM) value. To improve poor FOM value of pure ZnO thin films, boron (B) as a donor impurity was doped into the films. Direct-current magnetron sputtering was used to prepare B-doped ZnO (BZO) thin films from sintered ZnO targets with variable B2O3 content changing from 0 to 2 wt. %. The x ray diffraction analysis confirmed the preferably c-axis-oriented structure of hexagonal wurtzite ZnO host. The results also showed variation in the film structure versus the B2O3 content through calculations of crystal size and residual stress. Depending on the B2O3 content, a competition of interstitial and substitutional B3+ ions induced more stress or relaxation in lattice structure of the films. At 1% B2O3, the BZO thin film had the best crystalline characterization with the lowest stress and large crystal size. In consequence, the BZO 1% film obtained the lowest resistivity of 2.7×10-3Ωcm, average transmittance of 82.1%, and the best FOM value of 18.8×102Ω-1cm-1. The transparent-conducting performance of the ZnO thin films deposited by direct-current (DC) magnetron sputtering was significantly enhanced through B doping. The good-performance BZO film at 1% B2O3 is believed to be of use as electrodes in thin-film solar cells.

9.
Biochim Biophys Acta ; 1853(10 Pt A): 2432-43, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26149501

RESUMEN

The type I phosphatidylinositol 4-phosphate 5-kinase (PIP5K) family members and their lipid product, phosphatidylinositol 4,5-bisphosphate (PIP2) are important regulators of actin cytoskeleton. PIP5Kγ 90kDa (PIP5Kγ90), an isoform of PIP5K, localizes to focal adhesions (FAs) and is activated via its interaction with the cytoskeletal protein, talin. Currently, regulatory signaling pathways of talin-PIP5Kγ90 interaction related to FA dynamics and cell motility are not well understood. Considering the presence of Akt consensus motifs in PIP5Kγ90, we examined a potential link of Akt activation to talin-PIP5Kγ90 interaction. We found that Akt phosphorylated PIP5Kγ90 specifically at serine 555 (S555) in vitro and in epidermal growth factor (EGF)-treated cells phosphoinositide 3-kinase-dependently. EGF treatment suppressed talin-PIP5Kγ90 interaction and PIP2 levels. Similarly, a phosphomimetic mutant (S555D), but not non-phosphorylatable mutant (S555A), of PIP5Kγ90 had reduced talin binding affinity, lowered PIP2 levels, and was dislocated from FAs. The S555D mutant also caused decreases in actin stress fibers and vinculin-positive FAs. Moreover, assembly and disassembly of FAs were enhanced by S555D expression and EGF-induced cell migration was relatively low in S555A-expressing cells compared to wild-type-expressing cells. PIP5Kγ87, a PIP5Kγ splice variant lacking the talin binding motif, was phosphorylated by Akt, which, however, hardly affected PIP2 levels. Taken together, our results suggested that Akt-mediated PIP5Kγ90 S555 phosphorylation is a novel regulatory point for talin binding to control PIP2 level at the FAs, thereby modulating FA dynamics and cell motility.


Asunto(s)
Empalme Alternativo/fisiología , Movimiento Celular/fisiología , Adhesiones Focales/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Talina/metabolismo , Sustitución de Aminoácidos , Adhesiones Focales/genética , Células HeLa , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Mutación Missense , Fosforilación/fisiología , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Proteínas Proto-Oncogénicas c-akt/genética , Talina/genética
10.
Artículo en Inglés | MEDLINE | ID: mdl-27642246

RESUMEN

New diagnostic methods are needed for the accurate assessment of caries lesion activity to establish the need for surgical treatment. Detection of the highly mineralized surface layer that forms near the surface of the lesions as a result of remineralization is important for diagnosis of the lesion activity. Previous studies have demonstrated that novel imaging methods can be used to detect remineralization of artificial enamel caries lesions. In this paper, the activity of natural enamel caries lesions was assessed in-vitro via detection of the surface layer with PS-OCT and dehydration rate measurements with NIR reflectance and thermal imaging modalities. An automated approach for detecting the surface layer with PS-OCT yielded high sensitivity (= 0.79) and high specificity (= 0.93) with moderate correlation (R2 = 0.5920) with histology. Significant differences in dehydration rate measurements were found between the active and the arrested lesions using both the NIR reflectance and thermal imaging modalities. These results demonstrate that these novel imaging methods are ideally suited for nondestructive, noninvasive and quantitative measurement of lesion activity during a single clinical examination in real-time.

11.
J Biol Chem ; 288(8): 5645-59, 2013 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-23297396

RESUMEN

Phosphatidylinositol (PI) 4,5-bisphosphate (PIP(2)), generated by PI 4-phosphate 5-kinase (PIP5K), regulates many critical cellular events. PIP(2) is also known to mediate plasma membrane localization of the Toll/IL-1 receptor domain-containing adaptor protein (TIRAP), required for the MyD88-dependent Toll-like receptor (TLR) 4 signaling pathway. Microglia are the primary immune competent cells in brain tissue, and TLR4 is important for microglial activation. However, a functional role for PIP5K and PIP(2) in TLR4-dependent microglial activation remains unclear. Here, we knocked down PIP5Kα, a PIP5K isoform, in a BV2 microglial cell line using stable expression of lentiviral shRNA constructs or siRNA transfection. PIP5Kα knockdown significantly suppressed induction of inflammatory mediators, including IL-6, IL-1ß, and nitric oxide, by lipopolysaccharide. PIP5Kα knockdown also attenuated signaling events downstream of TLR4 activation, including p38 MAPK and JNK phosphorylation, NF-κB p65 nuclear translocation, and IκB-α degradation. Complementation of the PIP5Kα knockdown cells with wild type but not kinase-dead PIP5Kα effectively restored the LPS-mediated inflammatory response. We found that PIP5Kα and TIRAP colocalized at the cell surface and interacted with each other, whereas kinase-dead PIP5Kα rendered TIRAP soluble. Furthermore, in LPS-stimulated control cells, plasma membrane PIP(2) increased and subsequently declined, and TIRAP underwent bi-directional translocation between the membrane and cytosol, which temporally correlated with the changes in PIP(2). In contrast, PIP5Kα knockdown that reduced PIP(2) levels disrupted TIRAP membrane targeting by LPS. Together, our results suggest that PIP5Kα promotes TLR4-associated microglial inflammation by mediating PIP(2)-dependent recruitment of TIRAP to the plasma membrane.


Asunto(s)
Fosfotransferasas (Aceptor de Grupo Alcohol)/fisiología , Receptor Toll-Like 4/metabolismo , Animales , Línea Celular , Membrana Celular/metabolismo , Ensayo de Inmunoadsorción Enzimática/métodos , Células HEK293 , Células HeLa , Humanos , Inflamación , Interleucina-1/metabolismo , Glicoproteínas de Membrana/metabolismo , Ratones , Microglía/metabolismo , Óxido Nítrico/química , Receptores de Interleucina-1/metabolismo , Transducción de Señal , Factores de Tiempo
12.
Blood ; 119(3): 717-26, 2012 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-22101896

RESUMEN

Alterations of the BM microenvironment have been shown to occur after chemoradiotherapy, during aging, and after genetic manipulations of telomere length. Nevertheless, whether BM stromal cells adopt senescent features in response to these events is unknown. In the present study, we provide evidence that exposure to ionizing radiation (IR) leads murine stromal BM cells to express senescence markers, namely senescence-associated ß-galactosidase and increased p16(INK4a)/p19(ARF) expression. Long (8 weeks) after exposure of mice to IR, we observed a reduction in the number of stromal cells derived from BM aspirates, an effect that we found to be absent in irradiated Ink4a/arf-knockout mice and to be mostly independent of the CFU potential of the stroma. Such a reduction in the number of BM stromal cells was specific, because stromal cells isolated from collagenase-treated bones were not reduced after IR. Surprisingly, we found that exposure to IR leads to a cellular nonautonomous and Ink4a/arf-dependent effect on lymphopoiesis. Overall, our results reveal the distinct sensitivity of BM stromal cell populations to IR and suggest that long-term residual damage to the BM microenvironment can influence hematopoiesis in an Ink4a/arf-dependent manner.


Asunto(s)
Factor 1 de Ribosilacion-ADP/fisiología , Médula Ósea/efectos de la radiación , Senescencia Celular/efectos de la radiación , Inhibidor p16 de la Quinasa Dependiente de Ciclina/fisiología , Homeostasis/efectos de la radiación , Radiación Ionizante , Células del Estroma/efectos de la radiación , Animales , Apoptosis , Western Blotting , Médula Ósea/metabolismo , Médula Ósea/patología , Diferenciación Celular , Proliferación Celular , Femenino , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/patología , Células Madre Hematopoyéticas/efectos de la radiación , Linfopoyesis/efectos de la radiación , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Células del Estroma/metabolismo , Células del Estroma/patología
13.
Nat Commun ; 15(1): 2435, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38499573

RESUMEN

The potential of immune checkpoint inhibitors (ICI) may be limited in situations where immune cell fitness is impaired. Here, we show that the efficacy of cancer immunotherapies is compromised by the accumulation of senescent cells in mice and in the context of therapy-induced senescence (TIS). Resistance to immunotherapy is associated with a decrease in the accumulation and activation of CD8 T cells within tumors. Elimination of senescent cells restores immune homeostasis within the tumor micro-environment (TME) and increases mice survival in response to immunotherapy. Using single-cell transcriptomic analysis, we observe that the injection of ABT263 (Navitoclax) reverses the exacerbated immunosuppressive profile of myeloid cells in the TME. Elimination of these myeloid cells also restores CD8 T cell proliferation in vitro and abrogates immunotherapy resistance in vivo. Overall, our study suggests that the use of senolytic drugs before ICI may constitute a pharmacological approach to improve the effectiveness of cancer immunotherapies.


Asunto(s)
Neoplasias , Microambiente Tumoral , Animales , Ratones , Inmunoterapia , Neoplasias/patología , Senescencia Celular
14.
J Cell Sci ; 124(Pt 1): 68-81, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21118958

RESUMEN

DNA damage can induce a tumor suppressive response termed cellular senescence. Damaged senescent cells permanently arrest growth, secrete inflammatory cytokines and other proteins and harbor persistent nuclear foci that contain DNA damage response (DDR) proteins. To understand how persistent damage foci differ from transient foci that mark repairable DNA lesions, we identify sequential events that differentiate transient foci from persistent foci, which we term 'DNA segments with chromatin alterations reinforcing senescence' (DNA-SCARS). Unlike transient foci, DNA-SCARS associate with PML nuclear bodies, lack the DNA repair proteins RPA and RAD51, lack single-stranded DNA and DNA synthesis and accumulate activated forms of the DDR mediators CHK2 and p53. DNA-SCARS form independently of p53, pRB and several other checkpoint and repair proteins but require p53 and pRb to trigger the senescence growth arrest. Importantly, depletion of the DNA-SCARS-stabilizing component histone H2AX did not deplete 53BP1 from DNA-SCARS but diminished the presence of MDC1 and activated CHK2. Furthermore, depletion of H2AX reduced both the p53-dependent senescence growth arrest and p53-independent cytokine secretion. DNA-SCARS were also observed following severe damage to multiple human cell types and mouse tissues, suggesting that they can be used in combination with other markers to identify senescent cells. Thus, DNA-SCARS are dynamically formed distinct structures that functionally regulate multiple aspects of the senescent phenotype.


Asunto(s)
Ciclo Celular/efectos de la radiación , Núcleo Celular/efectos de la radiación , Senescencia Celular/efectos de la radiación , Cromatina/metabolismo , Citocinas/metabolismo , Daño del ADN/efectos de la radiación , Animales , Línea Celular , Núcleo Celular/genética , Núcleo Celular/metabolismo , Cromatina/genética , Citocinas/genética , Histonas/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteína de la Leucemia Promielocítica , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo , Rayos X
15.
Diagnostics (Basel) ; 13(17)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37685362

RESUMEN

The aim of this clinical study was to compare the diagnostic performance of dual short wavelength infrared (SWIR) occlusal transillumination and reflectance multispectral imaging with conventional visual assessment and radiography for caries detection on premolars scheduled for extraction for orthodontics reasons. Polarized light microscopy (PLM) and micro-computed tomography (microCT) performed after tooth extraction were used as gold standards. The custom-fabricated imaging probe was 3D-printed and the imaging system employed a SWIR camera and fiber-optic light sources emitting light at 1300 nm for occlusal transillumination and 1600 nm for reflectance measurements. Teeth (n = 135) on 40 test subjects were imaged in vivo using the SWIR imaging prototype in the study and teeth were extracted after imaging. Our study demonstrates for the first time that near-simultaneous real-time transillumination and reflectance video can be successfully acquired for caries detection. Both SWIR imaging modalities had markedly higher sensitivity for lesions on proximal and occlusal surfaces compared to conventional methods (visual and radiographic). Reflectance imaging at 1600 nm had higher sensitivity and specificity than transillumination at 1300 nm. The combined SWIR methods yielded higher specificity but the combined sensitivity was lower than for each individual method.

16.
Diagnostics (Basel) ; 13(3)2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36766570

RESUMEN

The active surveillance of root caries lesions to monitor potential remineralization or decay progression is challenging for the clinician, due to unreliable diagnostic information. The conventional visual and tactile methods for assessing the lesion activity are not reliable, and the clinician is often unable to determine if the lesion is progressing or has been arrested. An important marker of an arrested lesion is a highly mineralized transparent surface zone (TSL) that forms when the mineral is deposited in the outer layer of the lesion. The purpose of this study was to determine if cross-polarization optical coherence tomography (CP-OCT) could be used to detect changes in the lesion severity and activity during active monitoring. In total, 18 subjects with 22 suspected active root caries lesions were evaluated using CP-OCT at the baseline, 3 months, and 6 months. All subjects were instructed to use a high fluoride dentifrice at the baseline. The results showed that CP-OCT was able to discriminate the active from the arrested lesions by identifying the presence of a TSL on arrested lesions. The results also indicated that the mean TSL thickness increased significantly (p < 0.05) for the nine lesion areas. In addition, CP-OCT was able to show the progression of demineralization, erosion, and changes in gingival contours in scanned areas. CP-OCT was valuable for monitoring the activity and severity of root caries lesions in vivo. CP-OCT can be used to assess the activity of root caries lesions at a single time point by detecting the presence of a TSL at the lesion surface indicative of the lesion arrest.

17.
ACS Omega ; 8(44): 41258-41272, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37970056

RESUMEN

In this study, geopolymer originating from locally industrial byproducts as red mud (RM) was successfully prepared in the presence of different loadings of rice husk ash (RHA) used for the adsorption of methylene blue (MB) in wastewater. During geopolymerization, various mixing amounts between RM and RHA were conducted when the weight ratio of binder solution/activated alkali-metal solution (Na2SiO3/ NaOH 7 M) was 2.5 and the curing temperature was set at 60 °C for 24 h. As a result, the surface area value of the prepared geopolymer composited with RHA at 0 and 60% was increased from 19.2 to 29.5 m2/g, while the BJH pore size of the prepared geopolymer was reduced to 6.68 and 5.76 nm, respectively. In the dye removal test, higher additions of RHA in the RM-geopolymer maintained better retention of the MB ion due to the increase in the adsorption binding site. The maximum uptake amount of dyes performed at pH 8 was changed from 6.59 to 10.74 mg/g, while RHA was from 0 to 60% after 180 min of immersion in MB solution. The adsorption isotherms well obeyed the Langmuir model, as the relative coefficient R2 was 0.999. Based on these, the initial agricultural waste as RHA and industrial byproducts as RM were valued as functional materials used for dye treatment in wastewater.

18.
Cancer Cell Int ; 12: 10, 2012 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-22443202

RESUMEN

BACKGROUND: Although the primary risk factors for developing oral cancers are well understood, less is known about the relationship among the secondary factors that may modulate the progression of oral cancers, such as high-risk human papillomavirus (HPV) infection and folic acid (FA) supplementation. This study examined high-risk HPV and FA supplementation effects, both singly and in combination, to modulate the proliferative phenotypes of the oral cancer cell lines CAL27, SCC25 and SCC15. RESULTS: Using a comprehensive series of integrated in vitro assays, distinct effects of HPV infection and FA supplementation were observed. Both high-risk HPV strains 16 and 18 induced robust growth-stimulating effects in CAL27 and normal HGF-1 cells, although strain-specific responses were observed in SCC25 and SCC15 cells. Differential effects were also observed with FA administration, which significantly altered the growth rate of the oral cancer cell lines CAL27, SCC15, and SCC25, but not HGF-1 cells. Unlike HPV, FA administration induced broad, general increases in cell viability among all cell lines that were associated with p53 mRNA transcriptional down-regulation. None of these cell lines were found to harbor the common C677T mutation in methylenetetrahydrofolate reductase (MTHFR), which can reduce FA availability and may increase oral cancer risk. CONCLUSION: Increased FA utilization and DNA hypermethylation are common features of oral cancers, and in these cell lines, specifically. The results of this study provide further evidence that FA antimetabolites, such as Fluorouracil (f5U or 5-FU) and Raltitrexed, may be alternative therapies for tumors resistant to other therapies. Moreover, since the incidence of oral HPV infection has been increasing, and can influence oral cancer growth, the relationship between FA bioavailability and concomitant HPV infection must be elucidated. This study is among the first pre-clinical studies to evaluate FA- and HPV-induced effects in oral cancers, both separately and in combination, which provides additional rationale for clinical screening of HPV infection prior to treatment.

19.
Hematol Rep ; 14(2): 73-84, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35466176

RESUMEN

Introduction: The haematology external quality assessment (EQA) scheme is the most commonly used service of quality assurance. The provision of complete blood count (CBC) materials must meet the quality requirements at a reasonable cost. These requirements are the most significant challenges for EQA organisers in Vietnam. This study's objective was to evaluate the homogeneity, long-term stability, and peer-group performance of 10-parameter stabilised CBC EQA samples. Methods: The CBC EQA material was prepared using the following steps, including (1) adjusting levels of stabilised erythrocyte, leukocyte, and platelet samples, (2) mixing those cells into batches at three levels, and (3) dispensing and storing them at 2-6 °C. A set of 10 and 30 specimens were randomly chosen from each batch to study the homogeneity and long-term stability following ISO 13528:2015. In total, 166 samples at two levels were randomly distributed to 40 participants, which reported 83 automatic cell counters among six automated analyser models in the CBC EQA program. Results: The 10-parameter stabilised CBC EQA materials at three levels became homogeneous and stable in 12 weeks when preserved at 2-6 °C. Meanwhile, for five parameters (RBC, Hb, MCH, MCV, and MPV), this process was prolonged for up to 16 weeks in stock condition. In terms of peer-group performance, the CV (%) values increased at the low concentration for almost all parameters, especially in platelet counts. Conclusions: The stabilised CBC EQA samples prepared using the partial fixation method with aldehyde and gutaraldehyde in this study meet the ISO 13528:2015 requirements of homogeneity and long-term stability for the CBC EQA scheme. Analytical performance evaluation should categorise participant methods into peer groups.

20.
Cell Rep Methods ; 2(1): 100153, 2022 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-35474871

RESUMEN

Modeling the tumor-immune cell interactions in humanized mice is complex and limits drug development. Here, we generated easily accessible tumor models by transforming either primary skin fibroblasts or induced pluripotent stem cell-derived cell lines injected in immune-deficient mice reconstituted with human autologous immune cells. Our results showed that fibroblastic, hepatic, or neural tumors were all efficiently infiltrated and partially or totally rejected by autologous immune cells in humanized mice. Characterization of tumor-immune infiltrates revealed high expression levels of the dysfunction markers Tim3 and PD-1 in T cells and an enrichment in regulatory T cells, suggesting rapid establishment of immunomodulatory phenotypes. Inhibition of PD-1 by Nivolumab in humanized mice resulted in increased immune cell infiltration and a slight decrease in tumor growth. We expect that these versatile and accessible cancer models will facilitate preclinical studies and the evaluation of autologous cancer immunotherapies across a range of different tumor cell types.


Asunto(s)
Células Madre Pluripotentes Inducidas , Neoplasias , Ratones , Humanos , Animales , Células Madre Pluripotentes Inducidas/metabolismo , Receptor de Muerte Celular Programada 1 , Neoplasias/terapia , Nivolumab , Inmunoterapia/métodos
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