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1.
Cell Mol Biol (Noisy-le-grand) ; 70(5): 40-47, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38814236

ABSTRACT

Periodontal ligament stem cells (PDLSCs) show plasticity towards the adipogenic lineage; however, little has been done on the participation of epigenetic mechanisms. Histone acetylation is a dynamic process, though balanced by histone acetyltransferases (HATs) and histone deacetylases (HDACs) activities. This process can be halted by HDACs inhibitors, such as trichostatin A (TSA) and valproic acid (VPA). This study aimed to determine the role of HDACs class I in adipogenic differentiation of PDL cells. PDLSCs were treated with TSA at concentrations of 100, 200, and 250 nM, or VPA at 1, 4 and 8 mM. Cell viability was assessed using MTT assays. Gene expression of pluripotency markers (NANOG, OCT4, SOX2), HAT genes (p300, GCN5), and HDACs genes (HDAC1-3) was analyzed by RT-qPCR. Adipogenic differentiation was evaluated via oil red O staining, and acetylation of histone H3 lysine 9 (H3K9ac) was examined by Western blot. VPA treatment resulted in a 60% reduction in cell proliferation, compared to a 50% when using TSA. Cell viability was not affected by either inhibitor. Furthermore, both TSA and VPA induced adipogenic differentiation, through an increase in the deposition of lipid droplets and in GCN5 and p300 expression were observed. Western blot analysis showed that TSA increased H3K9ac levels on adipogenic differentiation of PDLSCs. These findings highlight the potential of HDAC inhibitors as a tool for modulating H3K9 acetylation status and thus influencing adipogenic differentiation of PDLCs.


Subject(s)
Adipogenesis , Cell Differentiation , Cell Survival , Histone Deacetylase Inhibitors , Periodontal Ligament , Valproic Acid , Humans , Periodontal Ligament/cytology , Periodontal Ligament/drug effects , Histone Deacetylase Inhibitors/pharmacology , Adipogenesis/drug effects , Adipogenesis/genetics , Valproic Acid/pharmacology , Cell Differentiation/drug effects , Cell Survival/drug effects , Acetylation/drug effects , Histone Deacetylases/metabolism , Histone Deacetylases/genetics , Hydroxamic Acids/pharmacology , Cells, Cultured , Histones/metabolism , Cell Proliferation/drug effects , Stem Cells/drug effects , Stem Cells/cytology , Stem Cells/metabolism
2.
Front Genet ; 14: 1037406, 2023.
Article in English | MEDLINE | ID: mdl-37614819

ABSTRACT

Colorectal cancer is a complex disease resulting from the interaction of genetics, epigenetics, and environmental factors. DNA methylation is frequently found in tumor suppressor genes to promote cancer development. Several factors are associated with changes in the DNA methylation pattern, and recently, the gastrointestinal microbiota could be associated with this epigenetic change. The predominant phyla in gut microbiota are Firmicutes and Bacteroidetes; however, an enrichment of Bacteroides fragilis, Fusobacterium nucleatum, and Streptococcus bovis, among others, has been reported in colorectal cancer, although the composition could be influenced by several factors, including diet, age, sex, and cancer stage. Fusobacterium nucleatum, a gram-negative anaerobic bacillus, is mainly associated with colorectal cancer patients positive for the CpG island methylator phenotype, although hypermethylation in genes such as MLH1, CDKN2A, MTSS1, RBM38, PKD1, PTPRT, and EYA4 has also been described. Moreover, Hungatella hathewayi, a gram-positive, rod-shaped bacterium, is related to hypermethylation in SOX11, THBD, SFRP2, GATA5, ESR1, EYA4, CDX2, and APC genes. The underlying epigenetic mechanism is unclear, although it could be implicated in the regulation of DNA methyltransferases, enzymes that catalyze the transfer of a methyl group on cytosine of CpG sites. Since DNA methylation is a reversible event, changes in gut microbiota could modulate the gene expression through DNA methylation and improve the colorectal cancer prognosis.

3.
Polymers (Basel) ; 15(7)2023 Mar 28.
Article in English | MEDLINE | ID: mdl-37050290

ABSTRACT

BACKGROUND: We assessed the effect of propolis on the antibacterial, mechanical, and adhesive properties of a commercial poly(alkenoate) cement. METHODS: The cement was modified with various concentrations of propolis, and antibacterial assays were performed against S. mutans by both MTT assays and agar diffusion tests. The compressive, flexural, and adhesive properties were also evaluated. RESULTS: the modified cement showed activity against S. mutans in both assays, although reductions in compressive (from 211.21 to 59.3 MPa) and flexural strength (from 11.1 to 6.2 MPa) were noted with the addition of propolis, while adhesive strength (shear bond strength and a novel pull-out method) showed a statistical difference (p < 0.05). CONCLUSION: the antiseptic potential of modified material against S. mutans will allow this material to be used in cases in which low mechanical resistance is required (in addition to its anti-inflammatory properties) when using atraumatic restorative techniques, especially in deep cavities.

4.
Int J Mol Sci ; 23(23)2022 Nov 26.
Article in English | MEDLINE | ID: mdl-36499146

ABSTRACT

It has been reported that chitosan scaffolds, due to their physicochemical properties, stimulate cell proliferation in different tissues of the human body. This study aimed to determine the physicochemical, mechanical, and biological properties of chitosan scaffolds crosslinked with ammonium hydroxide, with different pH values, to better understand cell behavior depending on the pH of the biomaterial. Scaffolds were either neutralized with sodium hydroxide solution, washed with distilled water until reaching a neutral pH, or kept at alkaline pH. Physicochemical characterization included scanning electron microscopy (SEM), elemental composition (EDX), Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy, thermogravimetric analysis (TGA), and mechanical testing. In vitro cytotoxicity was assessed via dental-pulp stem cells' (DPSCs') biocompatibility. The results revealed that the neutralized scaffolds exhibited better cell proliferation and morphology. It was concluded that the chitosan scaffolds' high pH (due to residual ammonium hydroxide) decreases DPSCs' cell viability.


Subject(s)
Chitosan , Humans , Chitosan/chemistry , Tissue Scaffolds/chemistry , Tissue Engineering/methods , Ammonium Hydroxide , Biocompatible Materials/pharmacology , Biocompatible Materials/chemistry , Spectroscopy, Fourier Transform Infrared , Porosity
5.
Medicine (Baltimore) ; 101(31): e29383, 2022 Aug 05.
Article in English | MEDLINE | ID: mdl-35945732

ABSTRACT

This study's objective was to compare the total and outside the cleft prevalence of dental anomalies (DA) between patients with cleft lip and palate (CLP) and a control group. This retrospective cross-sectional study was done under a case-control design. The case group consisted of 192 non-syndromic patients with complete CLP, while the control group included 411 patients. All subjects had orthopantomography, intra, and extraoral photographs. The prevalence of dental agenesis, supernumerary teeth, impacted teeth, dental transposition, and microdontia were compared using a chi-squared test (P < .05). Next, a second test was made, but only the anomalies outside the cleft were considered for this study. Total prevalence was 89.1% for cases, and 20.9% for controls (P < .01). The prevalence of each DA was significantly higher for the case group. In the analysis of DAs outside the cleft, the total prevalence was still significantly associated (P < .01); however, only dental agenesis was statistically significant (P < .01). Further analysis found that a high rate of upper premolar absence (P < .01) could explain this event. Patients with CLP have a higher prevalence of DAs compared to controls. After considering only the DAs outside the cleft, the total prevalence remains significantly higher. However, this phenomenon is explained mainly by the elevated prevalence of upper premolars' agenesis. This study's results suggest that environmental factors are behind the high prevalence of DAs in subjects with CLP.


Subject(s)
Cleft Lip , Cleft Palate , Tooth Abnormalities , Cleft Lip/epidemiology , Cleft Palate/epidemiology , Cross-Sectional Studies , Humans , Prevalence , Retrospective Studies , Tooth Abnormalities/epidemiology
6.
Front Cell Dev Biol ; 10: 791667, 2022.
Article in English | MEDLINE | ID: mdl-35281092

ABSTRACT

Obesity is a significant health concern that has reached alarming proportions worldwide. The overconsumption of high-energy foods may cause metabolic dysfunction and promote the generation of new adipocytes by contributing to several obesity-related diseases. Such concerns demand a deeper understanding of the origin of adipocytes if we want to develop new therapeutic approaches. Recent findings indicate that adipocyte development is facilitated by tight epigenetic reprogramming, which is required to activate the gene program to change the fate of mesenchymal stem cells (MSCs) into mature adipocytes. Like adipose tissue, different tissues are also potential sources of adipocyte-generating MSCs, so it is interesting to explore whether the epigenetic mechanisms of adipogenic differentiation vary from one depot to another. To investigate how DNA methylation (an epigenetic mark that plays an essential role in controlling transcription and cellular differentiation) contributes to adipogenic potential, dental pulp stem cells (DPSCs) and periodontal ligament stem cells (PLSCs) were analyzed during adipogenic differentiation in vitro. Here, we show that the capacity to differentiate from DPSCs or PLSCs to adipocytes may be associated with the expression pattern of DNA methylation-related genes acquired during the induction of the adipogenic program. Our study provides insights into the details of DNA methylation during the adipogenic determination of dental stem cells, which can be a starting point to identify the factors that affect the differentiation of these cells and provide new strategies to regulate differentiation and adipocyte expansion.

7.
J Pers Med ; 11(8)2021 Jul 28.
Article in English | MEDLINE | ID: mdl-34442382

ABSTRACT

Dental tissue-derived mesenchymal stem cells (DT-MSCs) are a promising resource for tissue regeneration due to their multilineage potential. Despite accumulating data regarding the biology and differentiation potential of DT-MSCs, few studies have investigated their adipogenic capacity. In this study, we have investigated the mesenchymal features of dental pulp stem cells (DPSCs), as well as the in vitro effects of different adipogenic media on these cells, and compared them to those of periodontal ligament stem cells (PLSCs) and dental follicle stem cells (DFSCs). DFSC, PLSCs, and DPSCs exhibit similar morphology and proliferation capacity, but they differ in their self-renewal ability and expression of stemness markers (e.g OCT4 andc-MYC). Interestingly, DFSCs and PLSCs exhibited more lipid accumulation than DPSCs when induced to adipogenic differentiation. In addition, the mRNA levels of adipogenic markers (PPAR, LPL, and ADIPOQ) were significantly higher in DFSCs and PLSCs than in DPSCs, which could be related to the differences in the adipogenic commitment in those cells. These findings reveal that the adipogenic capacity differ among DT-MSCs, features that might be advantageous to increasing our understanding about the developmental origins and regulation of adipogenic commitment.

8.
J Dent Sci ; 15(3): 336-344, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32952892

ABSTRACT

BACKGROUND/PURPOSE: Non-formation of a tooth impacts the morphology of the alveolar bone, which may, in turn, generate an imbalance in facial growth. This retrospective case-control study aimed to determine whether observable differences exist in the facial growth of patients with dental agenesis relative to complete dentition controls. MATERIALS AND METHODS: The sample comprised 75 patients with dental agenesis, and each case was paired with two controls of the same age and gender (n = 150). All patients were measured cephalometrically (31 variables), and both groups were compared with student's t- or Z-test (P < 0.05). Subsequently, ANOVA or Kruskal-Wallis tests (P < 0.05) were used to compare facial growth depending on the missing tooth's sagittal location in the dental arch (anterior or posterior agenesis); as well as its location in the affected bone (maxillary, mandibular, or both). RESULTS: Four measurements with significant differences were found, whereas ten were found in the sagittal location in the dental arch analysis. Regarding the affected bone, there were no affected variables. CONCLUSION: it was found that patients with dental agenesis show differences in the sagittal growth of the upper jaw and in the position of the lower incisor. In the studied population, these changes are strongly influenced by the sagittal location of the missing tooth, while its location in the jaws does not affect facial growth.

9.
Oral Health Prev Dent ; 18(1): 35-42, 2020.
Article in English | MEDLINE | ID: mdl-32051969

ABSTRACT

PURPOSE: To determine any associations between obesity and caries activity in the mixed dentition stage among primary school children in a low-income Mexican primary school. MATERIALS AND METHODS: This cross-sectional study was performed in Mexican schoolchildren aged 8-12 years. The body mass index (BMI) was obtained, and children were classified as overweight/obese considering age and sex. The experience of caries in permanent and temporary dentition was established with the sum of decayed/missing/filled teeth (DMFT or deft index for permanent or temporal dentition); a caries index for all teeth was also considered (total decay [TD]). Mann-Whitney U-test was used to contrast the distribution between sexes of the quantitative variables and to contrast the distribution of each variable per category, the Kruskal-Wallis test was used. Spearman's Rho test was used to establish the correlation between the quantitative variables. Multiple linear regression models were performed to find the relationship between the O'Leary index and the BMI. A Multilayer Perceptron was constructed as follows: (a) dependent variables: deft, DMFT, TD and O'Leary index; (b) factor: BMI; (c) covariable: age. RESULTS: A total of 331 children were included in the study. Dental caries prevalence was 32.4% (95% CI 29.7-35.2), while the mean DMFT was 0.64 (± SD 1.00). Through the Spearmen test, a statistically significant negative correlation was found between BMI-for-age with the total experience of carious lesions (r = -0.127, p = 0.021) and with experience of carious lesions in the deciduous dentition (deft) (r = -0.195, p ≤0.001). But when using the linear and logistic regression models to analyse the relationship with the O'Leary index, BMI was not statistically significant. With the Multilayer Perceptron there appears to be less error in the prediction of deft than the other indexes. CONCLUSIONS: This study confirms the high prevalence of obesity in primary school children. It also shows the scarce association between carious lesions and obesity.


Subject(s)
Dental Caries , Child , Cross-Sectional Studies , DMF Index , Humans , Mexico , Obesity , Prevalence
10.
PeerJ ; 7: e8212, 2019.
Article in English | MEDLINE | ID: mdl-31824782

ABSTRACT

BACKGROUND: Dental pulp (DP) represents an accessible and valuable source promising of stem cells for clinical application. However, there are some disadvantages associated with the isolation of dental pulp stem cells (DPSCs), which include the size and weight of the pulp tissue needed to yield sufficient cells for culturing in vitro. Therefore, the objective of this study was to compare in vitro histomorphometry of DP from permanent (premolars, third molar), supernumerary and deciduous teeth of patients between 5 and 25 years old with regards to weight, length, width and the cell density in the four regions of the DP in order to obtain quantitative parameters in a tissue that represents a valuable source of stem cells. METHODS: DPs were obtained from 10 central incisors deciduous, 20 permanent teeth (10 premolars, 10 third molars) and 10 supernumeraries (six mesiodents and four inferior premolar shapes). The pulps were carefully removed, and the entire tissue was weighed. The pulp length and the width were measured with a digital Vernier caliper. The cellular density analysis was performed according to the four regions of the DP (coronal, cervical, medial and apical) in histological slides using photography and the ImageJ® program for quantification. RESULTS: The Pearson correlation test revealed that DP weight among different types of teeth is correlated with age in male patients. A significant positive correlation was noted between length and width of the DP with age in both genders. The mean DP weight for supernumerary and third molar teeth was greater than deciduous and premolar teeth. Finally, the histological analysis showed that the coronal and apical portions of DP in supernumerary and premolar teeth have the highest cell density. CONCLUSIONS: The DP of supernumerary teeth has quantitatively the best morphometric parameters and cell density comparable with the quality of DP obtained from deciduous teeth.

11.
Int J Mol Sci ; 20(16)2019 Aug 12.
Article in English | MEDLINE | ID: mdl-31408999

ABSTRACT

Obesity is a rising public health problem that contributes to the development of several metabolic diseases and cancer. Adipocyte precursors outside of adipose depots that expand due to overweight and obesity may have a negative impact on human health. Determining how progenitor cells acquire a preadipocyte commitment and become mature adipocytes remains a significant challenge. Over the past several years, we have learned that the establishment of cellular identity is widely influenced by changes in histone marks, which in turn modulate chromatin structure. In this regard, histone lysine demethylases (KDMs) are now emerging as key players that shape chromatin through their ability to demethylate almost all major histone methylation sites. Recent research has shown that KDMs orchestrate the chromatin landscape, which mediates the activation of adipocyte-specific genes. In addition, KDMs have functions in addition to their enzymatic activity, which are beginning to be revealed, and their dysregulation seems to be related to the development of metabolic disorders. In this review, we highlight the biological functions of KDMs that contribute to the establishment of a permissive or repressive chromatin environment during the mesenchymal stem cell transition into adipocytes. Understanding how KDMs regulate adipogenesis might prompt the development of new strategies for fighting obesity-related diseases.


Subject(s)
Adipogenesis , Epigenesis, Genetic , Histone Demethylases/metabolism , Histones/metabolism , Adipocytes/cytology , Adipocytes/metabolism , Animals , Chromatin/genetics , Chromatin/metabolism , Histone Demethylases/genetics , Histones/genetics , Humans , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism
12.
Biomed Res Int ; 2017: 7431301, 2017.
Article in English | MEDLINE | ID: mdl-28685149

ABSTRACT

OBJECTIVE: To identify dental pain prevalence and associated factors in Mexican schoolchildren. METHODS: This cross-sectional study included 1,404 schoolchildren aged 6 to 12 years from public schools in the city of Pachuca de Soto, Hidalgo, Mexico. Data were collected through a questionnaire that addressed sociodemographic and socioeconomic factors, eating and dental hygiene habits, and behavior variables. The dependent variable was self-reported dental pain in the 12 months prior to the survey. Data were analyzed using nonparametric statistics and a binary logistical regression model. RESULTS: Dental pain prevalence among the studied children was 49.9%. The variables associated in the final model (p < 0.05) were younger mother's age, higher socioeconomic level, absence of an automobile in the home, fried food, fruit intake, lower tooth brushing frequency, never having used mouthwash or not knowing about it, and parents/guardians with regular to high levels of knowledge about oral health and a regular or good/very good perception of their child's oral health. CONCLUSIONS: One in two children in the study had experienced dental pain in the twelve months prior to the survey. The association of socioeconomic variables with dental pain suggested inequalities among the children in terms of oral health.


Subject(s)
Pain/epidemiology , Child , Cross-Sectional Studies , Female , Humans , Male , Mexico/epidemiology , Pain/physiopathology , Prevalence , Risk Factors , Socioeconomic Factors
13.
Int J Dent ; 2017: 7326061, 2017.
Article in English | MEDLINE | ID: mdl-28326102

ABSTRACT

Objective. We quantified the prevalence of impacted maxillary canines (IMC) and their association with other dental anomalies (DAs). Materials and Methods. A retrospective study was done with 860 patients 12 to 39 years of age. The prevalence of IMC was calculated and compared by sex. The sample was divided into a control group and an impaction group, and the prevalence was calculated in both for a series of anomalies: agenesis, supernumerary teeth, shape anomalies of the upper laterals (microdontia, peg and barrel shape, and talon cusp), fusion, gemination, other impacted teeth, transposition, and amelogenesis imperfecta. The prevalence values for both groups were compared (Pearson's χ2 test, p ≤ 0.05). Results. IMC were present in 6.04% of the sample with no difference by sex (p = 0.540). Other DAs occurred in 51.92% of the IMC group and in 20.17% of the controls (p < 0.05). Significant associations (p < 0.05) were identified between IMC and four other DAs: microdontia, barrel shape, other impacted teeth, and transposition. The prevalence of all anomalies was lower in the control group. Conclusion. IMC were seen in 6.04% of patients. Patients with this condition also had a higher prevalence of other DAs. These other anomalies should be used as risk indicators for early diagnosis.

14.
Rev Chilena Infectol ; 33(3): 293-7, 2016 Jun.
Article in Spanish | MEDLINE | ID: mdl-27598278

ABSTRACT

INTRODUCTION: Use of orthodontic appliances creates favorable conditions for growth of dental bacterial plaque. AIM: To establish if use of orthodontic appliance affects the presence of Candida species in the oral cavity in a group of pediatric patients. MATERIALS AND METHODS: We studied 60 patients between 4 and 10 years old, requiring treatment with orthodontic appliances. Samples were taken of the oral cavity before orthodontic treatment and six months after use began. Samples were inoculated in Sabouraud Dextrose Agar and Candida CHROMagar®. Candida species confirmation and identification was done by multiple PCR, and results analyzed with a chi-squared test. RESULTS: Candida presence was greater (p < 0,001) in the samples taken six months after use began than in the initial samples. Before treatment, the most frequently found species (percentage of studied patients) was C. albicans (8.3%), while after treatment it was C. tropicalis (20.0%). CONCLUSIONS: Use of orthodontic appliances in children increases Candida species presence in the oral cavity. Preventative measures should be taken to avoid oral candidiasis, particularly in immunosuppressed patients.


Subject(s)
Candida/isolation & purification , Mouth/microbiology , Orthodontic Appliances/microbiology , Candidiasis, Oral/etiology , Child , Child, Preschool , DNA, Fungal , Female , Humans , Male , Polymerase Chain Reaction , Risk Factors , Time Factors
15.
Rev. chil. infectol ; 33(3): 293-297, jun. 2016. ilus, tab
Article in Spanish | LILACS | ID: lil-791022

ABSTRACT

Introducción: El uso de aparatología ortodóntica crea condiciones favorables para el incremento de la placa bacteriana. Objetivo: Evaluar si el uso de aparatología ortodóntica influye en la presencia de especies de Candida en la cavidad oral, en un grupo de pacientes pediátricos. Material y Métodos: Se estudiaron 60 pacientes entre 4 y 10 años de edad, que requirieron tratamiento con aparatología ortodóntica. Se tomaron muestras de la cavidad oral al inicio del tratamiento ortodóntico y a los seis meses de uso. Las muestras fueron sembradas en Agar Dextrosa Sabouraud y CHROMagar® Candida. Las especies de Candida se confirmaron por RPC múltiple. Los resultados se analizaron con la prueba estadística de chi cuadrada. Resultados: La presencia de Candida fue mayor en las muestras tomadas a los seis meses de iniciado el tratamiento (p < 0,001). La especie más frecuente antes del tratamiento fue C. albicans (8,3%) y después del tratamiento fue C. tropicalis (20,0%). Conclusiones: El uso de aparatología ortodóntica influye en la presencia de especies de Candida, por lo que deben tomarse medidas preventivas para evitar su conversión en candidiasis oral, en especial, en pacientes inmunodeprimidos.


Introduction: Use of orthodontic appliances creates favorable conditions for growth of dental bacterial plaque. Aim: To establish if use of orthodontic appliance affects the presence of Candida species in the oral cavity in a group of pediatric patients. Materials and Methods: We studied 60 patients between 4 and 10 years old, requiring treatment with orthodontic appliances. Samples were taken of the oral cavity before orthodontic treatment and six months after use began. Samples were inoculated in Sabouraud Dextrose Agar and Candida CHROMagar®. Candida species confirmation and identification was done by multiple PCR, and results analyzed with a chi-squared test. Results: Candida presence was greater (p < 0,001) in the samples taken six months after use began than in the initial samples. Before treatment, the most frequently found species (percentage of studied patients) was C. albicans (8.3%), while after treatment it was C. tropicalis (20.0%). Conclusions: Use of orthodontic appliances in children increases Candida species presence in the oral cavity. Preventative measures should be taken to avoid oral candidiasis, particularly in immunosuppressed patients.


Subject(s)
Humans , Male , Female , Child, Preschool , Child , Orthodontic Appliances/microbiology , Candida/isolation & purification , Mouth/microbiology , Time Factors , Candidiasis, Oral/etiology , DNA, Fungal , Polymerase Chain Reaction , Risk Factors
16.
J Agric Food Chem ; 63(17): 4284-90, 2015 May 06.
Article in English | MEDLINE | ID: mdl-25897561

ABSTRACT

Characteristic vector analysis has been applied to near-infrared spectra to extract the main spectral information from hyperspectral images. For this purpose, 3, 6, 9, and 12 characteristic vectors have been used to reconstruct the spectra, and root-mean-square errors (RMSEs) have been calculated to measure the differences between characteristic vector reconstructed spectra (CVRS) and hyperspectral imaging spectra (HIS). RMSE values obtained were 0.0049, 0.0018, 0.0012, and 0.0012 [log(1/R) units] for spectra allocated into the validation set, for 3, 6, 9, and 12 characteristic vectors, respectively. After that, calibration models have been developed and validated using the different groups of CVRS to predict skin total phenolic concentration, sugar concentration, titratable acidity, and pH by modified partial least-squares (MPLS) regression. The obtained results have been compared to those previously obtained from HIS. The models developed from the CVRS reconstructed from 12 characteristic vectors present similar values of coefficients of determination (RSQ) and standard errors of prediction (SEP) than the models developed from HIS. RSQ and SEP were 0.84 and 1.13 mg g(-1) of skin grape (expressed as gallic acid equivalents), 0.93 and 2.26 °Brix, 0.97 and 3.87 g L(-1) (expressed as tartaric acid equivalents), and 0.91 and 0.14 for skin total phenolic concentration, sugar concentration, titratable acidity, and pH, respectively, for the models developed from the CVRS reconstructed from 12 characteristic vectors.


Subject(s)
Fruit/growth & development , Phenols/analysis , Spectroscopy, Near-Infrared/methods , Vitis/chemistry , Fruit/chemistry , Least-Squares Analysis , Models, Theoretical , Vitis/growth & development
17.
J Food Sci ; 72(1): S012-8, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17995892

ABSTRACT

The impact of lighting on minimally processed cauliflower packaged in 4 different film types (PVC and 3 P-Plus) has been measured and quantified. The effect on the sensorial quality of storage at 4 degrees C in darkness and partial or continuous lighting was evaluated. The gas concentrations in the packages and the weight losses were also determined. Atmosphere composition inside the packages depended on both the permeability of the film used for the packaging and exposure to light. Samples stored with lighting maintained the gaseous exchange between plant tissue and the atmosphere inside the packages for longer periods than in samples kept in darkness. This prompted a greater loss of water vapor as well as the development of atmospheres with low levels of O2 and high levels of CO2 in the samples packed with less permeable films. The most important aspect in sensory evaluation was color. In instrumental color evaluation, coordinates h* and L* were the main means for estimating color evolution. The presence of light accelerated browning in the cut zones. The development of abnormal coloring in these areas marked the end of shelf life for minimally processed cauliflower. Among the sensory attributes studied, color was the most affected by exposure to light. Samples packed in P-Plus 120 film displayed the lowest level of color deterioration in the cut zones. However, under lit conditions, the low permeability of this film caused atmospheres with very low O2 contents and high CO2 contents. These atmospheres produced a loss of texture and the development of off-odors.


Subject(s)
Brassica/radiation effects , Food Packaging/methods , Food Preservation/methods , Light , Pigmentation/radiation effects , Carbon Dioxide/analysis , Carbon Dioxide/metabolism , Consumer Behavior , Food Handling/methods , Humans , Light/adverse effects , Odorants/analysis , Oxygen/analysis , Oxygen/metabolism , Permeability , Taste
18.
J Opt Soc Am A Opt Image Sci Vis ; 23(8): 2020-6, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16835662

ABSTRACT

The division of Color Space into ten zones, corresponding to the ten Munsell hues, allows a good reconstruction of surface reflectance spectra using just three eigenvectors, obtained by applying principal components analysis to the reflectance spectra of the Munsell Atlas specimens (model group), although the basis vectors obtained are different for each subspace. The use of the tristimulus values from each measured spectrum, calculated with the Illuminant D65 and the Standard Observer CIE64 to obtain the principal components necessary to reconstruct the spectrum, allows a very high degree of metamerism to be attained between the two spectra (measured and reconstructed). Furthermore, this method of calculating the principal components allows reconstruction of the spectra of specimens from other sample sets that differ from the model group used in the PCA. The colorimetric accuracy obtained in the new sample sets is similar to that obtained for the model group.

19.
Arch Med Res ; 33(2): 144-7, 2002.
Article in English | MEDLINE | ID: mdl-11886712

ABSTRACT

BACKGROUND: Since the first organ transplantation in the 1950s, there have been reports that patients who underwent organ transplantation had a poor prognosis if they were depressed and/or anxious prior to transplantation. Our objective in this study was to determine the prevalence of anxiety and depression in the different stages of bone marrow transplantation (BMT). METHODS: Mood disorders (MD), anxiety disorders (AD), and adjustment disorders (ADD) were measured five times with DSM IV. The Beck Inventory of Depression (BID) and Hamilton Rating Scale of Anxiety (HRSA) were used to measure levels of depression and anxiety, respectively, at registration and at days -1, +21 +/- 7, +30 +/- 10, and 90 +/- 10 days from BMT. Analysis between diverse periods was made for allogeneic BMT (allo-BMT) with chi square test, while Fisher exact test was used for the autologous BMT (auto-BMT). RESULTS: We report on 26 patients, including 18 with allo-BMT, and eight with auto-BMT. The allo-BMT was associated with depression during post BMT period (chi(2) = 11.924; p = 0.01). Slight anxiety without statistical significance was found in all stages. There was a high prevalence of anxiety and adjustment disorder in the immediate posttransplantation stage. Anxiety and adjustment disorders were more frequently found in all posttransplantation stages, particularly in the immediate stage (chi(2) =11.104, p = 0.02). After 3 months, no survivor received a psychiatric diagnosis. We did not find any differences in MD. There were five deaths. CONCLUSIONS: The auto-BMT group did not show significant associations between different stages and psychiatric variables studied. One death occurred at 1 month. This patient had severe depression. We recommend that the depressive syndrome be intentionally researched during the different stages of BMT, specifically in the immediate transplantation stage.


Subject(s)
Anxiety , Bone Marrow Transplantation/psychology , Depression , Psychological Tests , Adolescent , Adult , Female , Humans , Male , Middle Aged , Transplantation, Autologous , Transplantation, Homologous
20.
Santiago de Chile; Salesianos; 2002. 286 p. ilus, graf.
Monography in Spanish | MINSALCHILE | ID: biblio-1543357
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