Cutaneous squamous cell carcinoma (cSCC) is a common skin cancer with metastatic potential. To reduce reoperations due to nonradical excision, there is a need to develop a technique for identification of tumor margins preoperatively. Photoacoustic (PA) imaging is a novel imaging technology that combines the strengths of laser optics and ultrasound. Our aim was to determine the spectral signature of cSCC using PA imaging and to use this signature to visualize tumor architecture and borders. Two‐dimensional PA images of 33 cSCCs and surrounding healthy skin were acquired ex vivo, using 59 excitation wavelengths from 680 to 970 nm. The spectral response of the cSCCs was compared to healthy tissue, and the difference was found to be greatest at wavelengths in the range 765 to 960 nm (P < .05). Three‐dimensional PA images were constructed from spectra obtained in the y‐z plane using a linear stepper motor moving along the x‐plane. Spectral unmixing was then performed which provided a clear three‐dimensional view of the distribution of tumor masses and their borders. 相似文献
A false‐colored and merged image of fresh, ex vivo rat kidney acquired using an excitation‐scanning hyperspectral imaging system. The spectral image was acquired using excitation wavelengths from 360 to 550 nm. Colors represent principal components extracted from a spectral image cube featuring no added labels or markers. Further details can be found in the article by Peter F. Favreau, Joshua A. Deal, Bradley Harris, et al. ( e201900183 ).
Diabetes is a serious disease whose patients often require long-term care. Blood glucose and intermediate glycation product of glycated hemoglobin (HbA1c) are, at best, surrogate biomarkers of disease progression. There is indication that advanced glycation end products (AGEs) better reflect diabetic risks. In this study, we explored the use of red blood cells (RBCs) and lysed hemoglobin (Hb) autofluorescence (AF) as potential biomarkers of diabetic complication. AF spectra measured under 370 nm excitation reveals that both RBC and Hb fluorescence in the 420 to 600 nm region. At early time points following diabetic induction in rats, AF increase in lysed Hb is more dramatic compared to that of RBCs. Moreover, we found significance variance of Hb autofluorescence despite relatively constant HbA1c levels. Furthermore, we found that although a correlation exists between AGE autofluorescence and HbA1c levels, the lack of complete correspondence suggests that the rate of AGE production differs significantly among different rats. Our results suggest that with additional development, both RBC and Hb autofluorescence from lysed RBCs may be used act long-term glycemic markers for diabetic complications in patients. 相似文献
Objective: The relationship of the levels of cariogenic bacterial species with periodontal status and decayed root surfaces was investigated in elderly Japanese subjects. Methods: Three hundred and sixty‐eight individuals (each 75 years old) were examined for periodontal status (pocket depth, attachment loss), root surface caries and salivary levels of mutans streptococci (MS) and lactobacilli (LB). Results: Values >4 mm of attachment loss (rAL4) and for average attachment loss (aAL) of sites measured were significantly higher in subjects with LB than those without. Multiple regression analysis also showed a correlation between aAL and rAL4 values with the presence of LB (aAL p = 0.003; rAL4 p = 0.002). Further, multiple regression analysis of interacting factors regarding decayed root surfaces showed that LB carriers had a greater incidence of decayed root surface caries (p = 0.003), while MS and LB levels were correlated to the number of decayed root surfaces (LB p = 0.010; MS p = 0.026). Conclusion: Our results indicate that considerable attachment loss elevates the possibility of having LB, thus increasing the risk of root surface caries. It was also found that LB and MS measurements may be useful indicators of decayed root surfaces in elderly individuals with attachment loss. 相似文献
Dental caries has been reported in a variety of primates, although it is still considered rare in wild populations. In this study, 11 catarrhine primate taxa (n = 339 individuals; 7946 teeth) were studied for the presence of caries. A differential diagnosis of lesions in interproximal regions of anterior teeth was undertaken, since they had been previously described as both carious and non-carious in origin. Each permanent tooth was examined macroscopically, with severity and position of lesions recorded. Two specimens were examined further, using micro-CT scans to assess demineralization. Differential diagnosis confirmed the cariogenic nature of interproximal cavities on anterior teeth (ICATs). Overall results show 3.3% of all teeth (i.e., anterior and posterior teeth combined) were carious (n = 262), with prevalence varying among species from 0% to >7% of teeth affected. Those with the highest prevalence of ICATs include Pan troglodytes verus (9.8% of anterior teeth), Gorilla gorilla gorilla (2.6%), Cercopithecus denti (22.4%), Presbytis femoralis (19.5%), and Cercopithecus mitis (18.3%). ICATs make up 87.9% of carious lesions on anterior teeth. These results likely reflect dietary and food processing differences among species, but also between the sexes (e.g., 9.3% of all female P. troglodytes verus teeth were carious vs. 1.8% in males). Processing cariogenic fruits and seeds with the anterior dentition (e.g., wadging) likely contributes to ICAT formation. Further research is needed in living primate populations to ascertain behavioral/dietary influences on caries occurrence. Given the presence of ICATs in frugivorous primates, their diagnosis in archaeological and paleontological specimens may shed light on diet and food processing behaviors in fossil primates. 相似文献
Objectives: This study compared a 10% chlorhexidine varnish treatment with placebo and sham treatments for preventing dental caries in adult patients with xerostomia (dry mouth). Design: The study was a multicentred, randomized, parallel group, double blind, placebo‐controlled clinical trial. Setting: All examinations and procedures were performed at Tuft's University, Boston, MA, the University of British Columbia, Vancouver, BC or the University of Western Ontario, London, ON. Subjects: Subjects were adults with recent or current dental caries experience, high salivary levels of cariogenic microorganisms and low salivary flow rates. Results: 236 subjects completed at least one post‐treatment examination. There were 697 new carious lesions diagnosed, 446 (64%) located on coronal surfaces and 251 (36%) located on root surfaces. The mean attack rate was 0.23 surfaces/100 surfaces at risk. A treatment difference observed between the Active and Placebo groups was statistically significant for root caries increment (p=.02) and total caries increment (p=.03). A treatment difference observed between the Active and Sham groups was not statistically significant for coronal, root or total caries increment. Analysis of variance of treatment group differences was performed using mutans streptococci counts, salivary flow rates, age, sex, caries prevalence, medications, time to first event and early withdrawal as co‐variables. These factors did not meaningfully alter the findings. Conclusions: The difference between the 10% chlorhexidine varnish and placebo treatments is considered to be highly clinically significant for root caries increment (41% reduction) and for total caries increment (25% reduction) but only for coronal caries increment (14%). 相似文献
Objective: The 10‐year incidence of dental caries was related to some associated factors in a random sample of 65, 75 and 85‐year‐old inhabitants of Gothenburg. Subjects: Of the 208 persons examined at baseline, 102 (49%) participated in the follow‐up examination; 56, 37 and nine, respectively, in the different age groups. For the purpose of time‐trend comparisons, a new random sample of 98 individuals aged 55 years was examined. Results: Ninety‐five per cent of the participants had developed one or more carious lesions during the 10‐year period and the incidence of coronal and root caries increased with age. In the 65‐year‐olds, 9% of the root surfaces had decayed during the period, compared with 25% in the 85‐year‐olds. Secondary caries predominated over primary caries and prosthetic crowns accounted for 70% of the restored tooth surfaces. Twenty per cent of the individuals were daily smokers and 61% were taking drugs with hyposalivatory side‐effects. The mean saliva secretion rates were lower in the older groups compared with the ‘younger’ ones. The overall salivary counts of mutans streptococci and lactobacilli had increased during the period and the values were highest in the oldest age groups. Salivary levels of lactobacilli and mutans streptococci, number of teeth, daily numbers of cigarettes and drugs and oral hygiene were the best predictors of the incidence of caries. Conclusion: The findings indicate that there is an increased risk of dental caries with age owing to unfavourable caries‐related factors. 相似文献
Fourier‐transform infrared hyperspectral imaging (FTIR‐HSI) provides hyperspectral images containing both morphological and chemical information. It is widely applied in the biomedical field to detect tumor lesions, even at the early stage, by identifying specific spectral biomarkers. Pancreatic neoplasms present different prognoses and are not always easily classified by conventional analyses. In this study, tissue samples with diagnosis of pancreatic ductal adenocarcinoma and pancreatic neuroendocrine tumor were analyzed by FTIR‐HSI and the spectral data compared with those from healthy and dysplastic samples. Multivariate/univariate approaches were complemented to hyperspectral images, and definite spectral markers of the different lesions identified. The malignant lesions were recognizable both from healthy/dysplastic pancreatic tissues (high values of phospholipids and triglycerides with shorter, more branched and less unsaturated alkyl chains) and between each other (different amounts of total lipids, phosphates and carbohydrates). These findings highlight different metabolic pathways characterizing the different samples, well detectable by FTIR‐HSI. 相似文献
A recent paper concerning characteristic groove-shaped wear in interproximal attritional facets of Neandertal posterior teeth
correlated groove formation with deep enamel structural traits (Villa & Giacobini, 1995). Further studies were carried out
on modern human teeth in order to evaluate a possible correlation between deep enamel structure and some crown complex morphological
features.
Seventy-five isolated molars from medieval and recent ossuaries as well as five molars recently extracted for therapeutic
purpose were examined using scanning electron and optic microscope ground sections of interproximal enamel. The results showed
possible correlations between deep enamel structural characteristics (i.e., Hunter-Schreger band verticalization) and some
crown complex traits (i.e., occlusal groove pattern, mesial and distalfovea, mesial and distal accessory tubercules, interproximal marginal ridges).
Observations reported in this study showed a significantly higher frequency of Hunter-Schreger band verticalization in lower
molars with an occlusal complex pattern (i.e. primitive fissure pattern “Y” or “+”). This observation suggests a positive
correlation among crown complex traits (which occur frequently in Neandertal teeth) with deep enamel structural characteristics.
In addition, analysis of teeth grouped according to individual showed crown morphological traits and deep enamel structural
characteristics corresponding to the same individual. This observation supports a genetic basis in occlusal shape and microstructural
dental traits. 相似文献
Hemolysis is a very common phenomenon and is referred as the release of intracellular components from red blood cells to the extracellular fluid. Hemolyzed samples are often rejected in clinics due to the interference of hemoglobin and intracellular components in laboratory measurements. Plasma and serum based vibrational spectroscopy studies are extensively applied to generate spectral biomarkers for various diseases. However, no studies have reported the effect of hemolysis in blood based vibrational spectroscopy studies. This study was undertaken to evaluate the effect of hemolysis on infrared and Raman spectra of blood plasma. In this study, prostate cancer plasma samples (n = 30) were divided into three groups (nonhemolyzed, mildly hemolyzed, and moderately hemolyzed) based on the degree of hemolysis and FTIR and Raman spectra were recorded using high throughput (HT)‐FTIR and HT‐Raman spectroscopy. Discrimination was observed between the infrared and Raman spectra of nonhemolyzed and hemolyzed plasma samples using principal component analysis. A classical least square fitting analysis showed differences in the weighting of pure components in nonhemolyzed and hemolyzed plasma samples. Therefore, it is worth to consider the changes in spectral features due to hemolysis when comparing the results within and between experiments. 相似文献
Objective: This study aimed to investigate the association between number of natural teeth and prevalence of root caries. Design: A cross‐sectional design was adopted. A stratified multi‐stage purposive sampling method was used to select a wide range of elderly people from all social classes, educational levels and sexes. Data was collected through interviews and clinical examinations. Setting: Urban area in Chiang Mai‐Thailand. Participants: 549 elderly dentate aged 60‐74 years. Main Outcome Measures: Teeth with decay and filled roots (DF‐T). Results: The prevalence of root caries was 18.2% with a mean DF‐T of 0.58 (S.D. 2.02). Results of multiple logistic regression showed that number of teeth, DMF‐S scores, sex, and socio economic factors were statistically significantly associated with root caries (P<0.05). Adjusted odds ratios demonstrated a 14% increase in the chance of having root caries when the number of teeth increased one unit. Similarly, a 3% increase was observed for each unit increase in the DMF‐S scores (p<0.001). Being male, having more than four years of education and earning more than 1500 baht/month increased the chances of root caries by 76%, 139% and 85% respectively (p<0.001). Recession and age were not statistically significantly associated with root caries. Conclusions: Having more teeth, higher DMF‐S scores, earning more than 1500 baht/month, having more than 4 years of education and being male increased the likelihood of having root caries. 相似文献
doi: 10.1111/j.1741‐2358.2011.00560.x Indicators for root caries in Danish persons with recently diagnosed Alzheimer’s disease Objective: To identify indicators of root caries among persons with newly diagnosed Alzheimer’s disease (AD). Background: Few studies have investigated dental caries in older adults with AD. Previously we found that persons with AD had significantly more root caries compared to persons with dementia other than AD. Methods: Participants were recruited from two university hospital clinics in Copenhagen, Denmark. A team of neurologists/geriatricians carried out the diagnostic screening. The study included an interview, oral examination and medical records. Results: We evaluated potential indicators of root decay across subjects with 3+ decayed surfaces vs. <3 decayed surfaces. Variables associated with increased odds of root caries were age over 80 years, 2+ decayed coronal surfaces and 5+ filled root surfaces. Among the social variables, living with someone was associated with a nearly 70% reduction in the odds of having 3+ surfaces of untreated caries. Discussion: Root caries is highly prevalent among individuals with new AD and there is still a strong need for active assessment of and attention to oral problems in persons with AD. Our findings document that recently diagnosed AD cases with multiple coronal caries lesions are at elevated risk of having more root caries. Also persons 81+ years and those with multiple root fillings are more likely to have numerous untreated root lesions. 相似文献
Several non‐invasive Raman spectroscopy‐based assays have been reported for rapid and sensitive detection of pathogens. We developed a novel statistical model for the detection of RNA viruses in saliva, based on an unbiased selection of a set of 65 Raman spectral features that mostly attribute to the RNA moieties, with a prediction accuracy of 91.6% (92.5% sensitivity and 88.8% specificity). Furthermore, to minimize variability and automate the downstream analysis of the Raman spectra, we developed a GUI‐based analytical tool “RNA Virus Detector (RVD).” This conceptual framework to detect RNA viruses in saliva could form the basis for field application of Raman Spectroscopy in managing viral outbreaks, such as the ongoing COVID‐19 pandemic. ( http://www.actrec.gov.in/pi-webpages/AmitDutt/RVD/RVD.html ). 相似文献
Objectives: (i) Initially, to devise and examine the validity of a system for determining lesion activity on root surfaces, and (ii) compare the effectiveness of two preventive programmes in controlling root caries in elderly people using the devised system. Materials and methods: (i) Four clinical variables: texture, contour, location and colour of root caries lesions were selected to evaluate lesion activity. The intraexaminer reproducibility of the scoring system was assessed on 28 elderly patients. The accuracy was assessed on 10 of these persons using an impression material (Clinpro, 3M ESPE). (ii) Of total, 215 homebound 75+ year olds were randomly assigned to one of three groups: group 1, once a month a dental hygienist brushed the teeth of the participants and applied Duraphat vanish to active root caries lesions. The participants in groups 2 and 3 received 5000 and 1450 ppm F‐toothpaste, respectively, to use twice a day. This study included an interview, a baseline examination and a final follow‐up examination after 8 months. Results: (i) Intraexaminer reproducibility of the root caries scoring system was 0.86 (Kappa). The sensitivity and specificity was 0.86 and 0.81. (ii) Data from those 189 (88%) who completed the study disclosed that there were no inter‐group differences at the baseline examination concerning relevant conditions. At the end of the study, the root caries status of participants in groups 1 and 2 had improved significantly when compared with group 3 (p < 0.02). No significant difference was observed between groups 1 and 2 (p = 0.14). Conclusion: The data suggest that the root caries scoring system is reliable. Both the intervention programmes controlled root caries development; the hygienist in eight of 10 persons, the 5000 ppm F‐toothpaste in seven of 10. In contrast, five of 10 participants who only brushed with 1450 ppm F‐toothpaste had root caries progression. 相似文献
We hypothesized that the anterior component of occlusal force (ACF) generated by mandibular molars was a function of molar inclination, height of the transverse condylar axis above the occlusal plane, steepness of the occlusal plane, gape, molar root dimensions, interproximal tooth contact force when not biting, and bite force. Our research aim was to identify those biomechanical factors which determine ACF. Mandibular second molars were axially loaded with a 90 N force (10 mm second molar gape) in 15 subjects, and the resulting ACF was measured at the mandibular first molar-second premolar contact using a recording technique based on interproximal frictional forces. Morphologic measurements were obtained from lateral cephalometric radiographs of each subject and included: Frankfort mandibular plane angle, occlusal plane angle, angles formed by the longitudinal axis of the second molar and the occlusal and mandibular planes, perpendicular distance from the top of the condyle to the occlusal plane, and second molar root width and root length. For ten subjects, ACF resulting from axial loads of 50, 100, 150, and 200 N was measured. For ten subjects, ACF resulting from an axial load of 50 N and second molar gapes of 10 mm, 14 mm, 18 mm, and 22 mm were measured. ACF increased with increasing gape and increased proportionally to increasing bite force. Correlation and stepwise regression analyses revealed that ACF varies with interproximal tooth contact force when not biting (contact ‘tightness’) and molar root width (model R2 = 0.71, p < 0.01). The hypothesis that ACF is a function of bite force, gape, molar root width, and interproximal contact tightness has been supported, and the hypothesis that ACF is a function of molar inclination, occlusal plane steepness, condylar axis height, and root length was rejected. 相似文献
This study measured the incidence of dental caries for one year and identified factors associated with the risk of caries in a sample of 156 elderly subjects. The subjects were examined at baseline and after one year to record the number of missing, filled and decayed teeth, to measure oral hygiene and flow of saliva, and to estimate the numbers of Streptococcus mutans and Lactobacilli cultured from samples of saliva. All subjects were interviewed on both occasions for information on their use of medications and dental services and on their ingestion of sugar. At baseline the elders had a mean of 19 natural teeth with 5 decayed surfaces (DS), 38 filled surfaces and a mean Plaque Index (PI) of 1. The independent group, on average, had more teeth and fillings but a lower PI and less caries. At the end of the year more than two-thirds (71%) of the 98 institutionalised subjects and over half (59%) of the 58 independent subjects had at least one new decayed/filled surface (DFS). The mean net DFS increment per subject was 4.6 and 2.0 respectively. Regression analyses on multivariate models identified caries at baseline, residence in long term care facilities, high numbers of Lactobacilli, poor oral hygiene and frequent sugar consumption as the variables contributing most significantly to the risk of caries in old age. 相似文献