Relationship between tooth type and material used in the construction of endocrowns and fracture force values: a systematic review.

OBJECTIVE: The aim of this study was to summarize the results of the endocrown (EC) studies that compared tooth preparation designs, tooth types, and ceramic material types in relation to fracture force values. MATERIALS AND METHODS: A full literature search was conducted in Web of Science, PubMed/Medline, EMBASE, Scopus, Cochrane Library, Google Scholar, and ProQuest electronic databases. The following keywords: Endocrown [(molar(s)) or (premolar(s) or (posterior teeth)] and Ceramic materials as (Lithium disilicate glass-ceramic; Zirconia; Lava Ultimate) and (fracture strength) or (fatigue) were used. Articles were manually searched utilizing their reference lists. Study selection was not restricted or limited to the time of publication, type of tested tooth, ceramic material, and EC design. RESULTS: A total of 34 laboratory studies published between 2008 and 2023 were included in this systemic review. Twelve studies were published in the last 3 years, the mandibular molar was examined by 14 studies, and premolars in both arches were investigated, followed by premolars in both arches. Lithium disilicate glass-ceramic (LDGC) was the most used material for EC testing, followed by LAVA Ultimate and zirconia materials. The EC design with a 2 mm extension inside the pulp (14 studies) was the most used. Fracture forces of maxillary molars or premolars were nearly equal and lower than those of mandibular molars. Differences among the fracture forces of the tested ceramic materials were marginal. EC with 2 mm deep inside the pulp showed the highest fracture force. CONCLUSIONS: Mandibular EC molars showed the highest fracture forces, followed by maxillary premolars and molars. No differences among the EC materials in the 2- and 4-mm pulpal extension designs were found, which had higher fracture forces than other designs.

A non-second-gradient model for nonlinear elastic bodies with fibre stiffness.

In the past, to model fibre stiffness of finite-radius fibres, previous finite-strain (nonlinear) models were mainly based on the theory of non-linear strain-gradient (second-gradient) theory or Kirchhoff rod theory. We note that these models characterize the mechanical behaviour of polar transversely isotropic solids with infinitely many purely flexible fibres with zero radius. To introduce the effect of fibre bending stiffness on purely flexible fibres with zero radius, these models assumed the existence of couple stresses (contact torques) and non-symmetric Cauchy stresses. However, these stresses are not present on deformations of actual non-polar elastic solids reinforced by finite-radius fibres. In addition to this, the implementation of boundary conditions for second gradient models is not straightforward and discussion on the effectiveness of strain gradient elasticity models to mechanically describe continuum solids is still ongoing. In this paper, we develop a constitutive equation for a non-linear non-polar elastic solid, reinforced by embedded fibers, in which elastic resistance of the fibers to bending is modelled via the classical branches of continuum mechanics, where the development of the theory of stresses is based on non-polar materials; that is, without using the second gradient theory, which is associated with couple stresses and non-symmetric Cauchy stresses. In view of this, the proposed model is simple and somewhat more realistic compared to previous second gradient models.

Transitions from pediatric to adult rheumatology care for juvenile idiopathic arthritis: a patient led qualitative study.

BACKGROUND: Juvenile idiopathic arthritis (JIA) is a childhood autoimmune disease that causes swelling and pain in at least one joint. Young people with JIA experience symptoms that persist into adulthood, and thus will undergo a transition including the o transfer of care from a pediatric rheumatologist an adult rheumatologist. Missing from the literature is research that centres the transition experience of young people with JIA in Canada. This goal of this patient-led research was to explore the experience young people with JIA through the process of transition. METHODS: Qualitative study using the Patient and Community Engaged Research (PaCER) approach. Trained patient-researchers conducted three focus groups using the Set, Collect and Reflect PaCER process. Participants, recruited via purposive and snowball sampling using research/personal networks and social media, were young people with JIA in Canada between 18 and 28 years who had experienced with the process of transition to adult care. Recordings were transcribed verbatim. Patient researchers individually coded overlapping sections of the data, and thematic analysis was conducted. RESULTS: In total, nine individuals participated in one or more focus groups. Three themes were identified, with sub-themes: preparedness for transition (readiness for the transfer of care, developing self-advocacy skills), continuity and breadth of care (changing relationships, culture shock, new responsibilities), need for support (social support, mental health support, and ongoing support needs - beyond the transfer of care. Peer support was a connecting concept in the support sub-themes. Transition was more than a change in primary physician but also a change in the care model and breadth of care provided, which was challenging for young people especially if they had insufficient information. CONCLUSIONS: Transition from pediatric to adult care in rheumatology is a significant period for young people living with JIA, and this patient-led study provided insight into the experience from the perspective of young people with JIA which is critical to informing the development of supports for patients through the process. Patients, caregivers, pediatric and adult rheumatologists and members of the multi-disciplinary care team need to collaborate in terms of resources preparing for transfer, and support throughout the transition process to ensure a successful transition process.

The truth, the whole truth, and nothing but the truth: Therapeutic privilege.

The term therapeutic privilege is unfamiliar in the medical field and often sparks questions and discomfort about its ethical implications. Therapeutic privilege refers to the act of withholding information by a clinician, with the underlying notion that the disclosure of this information would inflict harm or suffering upon the patient. This is a case of a 56-year-old woman who presented to our facility under critical conditions. She developed sepsis with acute respiratory failure, requiring intubation and mechanical ventilation. Prior to her admission, her husband had been admitted at our facility's intensive care unit. On the same day when our patient was extubated, her husband had died. The palliative care team was consulted to assist with disclosing this information to the patient in light of her emotional fragility, her anxiety, and concerns for her ability to receive such news given her own active illnesses.

Enhanced inhibition of Pseudomonas aeruginosa virulence factor production and biofilm development by sublethal concentrations of eugenol and phenyllactic acid.

Biofilm development in Pseudomonas aeruginosa is regulated by its quorum sensing (QS) systems. It has three major QS systems: LasI/R, RhlI/R and PQS/MvfR. Previous studies showed that phenyllactic acid (PLA) binds to RhlR and PqsR and inhibits the Rhl and PQS QS; and eugenol at sublethal concentration inhibits Las and PQS QS systems. Here, we have demonstrated that a combination of sublethal doses of eugenol and PLA enhanced the inhibition of the QS mediated production of the virulence factors and biofilm development of this pathogen. A combination of 50 µmol l-1 eugenol and 0·3 mmol l-1 PLA significantly inhibited the pyocyanin production, protease activity, swarming motility and cytotoxic activities of P. aeruginosa strain PAO1, whereas eugenol and PLA when added individually to PAO1 cultures were less effective in inhibiting its virulence factor expression. Biofilm formation of PAO1 was reduced by 32, 19 and 87% on glass surfaces; and 54, 49 and 93% on catheter surfaces when treated using 50 µmol l-1 eugenol or 0·3 mmol l-1 PLA and their combinations, respectively. The in vitro finding in the reduction of biofilm development was further validated in vivo using a catheter associated medaka fish biofilm model. Our results indicate that a combination of QS inhibitors targeting different QS pathways should be selected while designing therapeutic molecules to achieve maximum QS mediated biofilm inhibition and clinical outcome against P. aeruginosa.

A generalized strain approach to anisotropic elasticity.

This work proposes a generalized Lagrangian strain function [Formula: see text] (that depends on modified stretches) and a volumetric strain function [Formula: see text] (that depends on the determinant of the deformation tensor) to characterize isotropic/anisotropic strain energy functions. With the aid of a spectral approach, the single-variable strain functions enable the development of strain energy functions that are consistent with their infinitesimal counterparts, including the development of a strain energy function for the general anisotropic material that contains the general 4th order classical stiffness tensor. The generality of the single-variable strain functions sets a platform for future development of adequate specific forms of the isotropic/anisotropic strain energy function; future modellers only require to construct specific forms of the functions [Formula: see text] and [Formula: see text] to model their strain energy functions. The spectral invariants used in the constitutive equation have a clear physical interpretation, which is attractive, in aiding experiment design and the construction of specific forms of the strain energy. Some previous strain energy functions that appeared in the literature can be considered as special cases of the proposed generalized strain energy function. The resulting constitutive equations can be easily converted, to allow the mechanical influence of compressed fibres to be excluded or partial excluded and to model fibre dispersion in collagenous soft tissues. Implementation of the constitutive equations in Finite Element software is discussed. The suggested crude specific strain function forms are able to fit the theory well with experimental data and managed to predict several sets of experimental data.

Gastrointestinal tuberculosis: A systematic review of epidemiology, presentation, diagnosis and treatment.

Tuberculosis (TB) once considered a disease of the developing world is infrequent in the developing world too. Its worldwide prevalence with a huge impact on the healthcare system both in economic and health terms has prompted the World Health Organization to make it a top priority infectious disease. Tuberculous infection of the pulmonary system is the most common form of this disease, however, extrapulmonary TB is being increasingly recognized and more often seen in immunocompromised situations. Gastrointestinal TB is a leading extrapulmonary TB manifestation that can defy diagnosis. Overlap of symptoms with other gastrointestinal diseases and limited accuracy of diagnostic tests demands more awareness of this disease. Untreated gastrointestinal TB can cause significant morbidity leading to prolonged hospitalization and surgery. Prompt diagnosis with early initiation of therapy can avoid this. This timely review discusses the epidemiology, risk factors, pathogenesis, clinical presentation, current diagnostic tools and therapy.

Phenotypic and Molecular Characterization of ß-Lactamases among Enterobacterial Uropathogens in Southeastern Nigeria.

Little is known about the molecular basis of antibiotic resistance among uropathogens in Southeast Nigeria. The aim of the study was to characterize enterobacterial uropathogens with respect to drug resistance. One hundred (100) enterobacterial uropathogens were studied. Their antibiotic susceptibility patterns were evaluated using disk diffusion, screened, and confirmed phenotypically for the presence of ß-lactamases: ESBL, AmpC, carbapenemase, and MBLs. Screen positives were further tested for various ß-lactamase genes by PCR. Our isolates showed variable resistance to most drugs tested. Out of the 58 ESBL screen positive E. coli, 35 were confirmed positive with PCR. The predominant ESBL gene was blaTEM while blaSPM was the most prevalent among MBL genes. Forty-six percentage of the screen positive Salmonella isolates coharbored blaTEM + SHV genes. Nine of the 10 ESBL screen positive K. pneumoniae were phenotypically and PCR positive. Three isolates of K. pneumoniae were positive for MBL genes. All the 10 C. freundii were positive for ESBL genes. The study showed high prevalence of drug-resistant genes among the enterobacterial uropathogens. Majority of the uropathogens harbored >1 antibiotic-resistant gene, and the most predominant gene was ESBL (blaTEM) followed by the MBL (SPM) gene.

Molecular chemisorption of N2 on IrO2(110).

We investigated adsorption of N2 on stoichiometric and O-rich IrO2(110) surfaces using temperature programmed desorption (TPD) experiments and density functional theory (DFT) calculations. TPD shows that N2 desorbs predominantly from the stoichiometric-IrO2(110) surface in a well-defined peak at 270 K for N2 coverages below about 0.5 ML and that a shoulder centered near 235 K develops in the N2 TPD traces as the coverage approaches saturation, indicating that adsorbed N2 molecules destabilize at high N2 coverages. Experiments of N2 adsorption onto O-rich IrO2(110) surfaces provide evidence that N2 adsorbs exclusively on the coordinatively unsaturated Ir atoms (Ircus) of the surface and that pre-adsorbed O-atoms ("on-top" oxygen) stabilize adsorbed N2 molecules, causing the main N2 TPD peak to shift toward higher temperature with increasing oxygen coverages. Consistent with prior results, our DFT calculations predict that an N2 molecule preferentially adsorbs into an upright configuration on an Ircus atom of the IrO2(110) surface and achieves a binding energy of about 100 kJ/mol. The computed binding energy agrees well with our experimental estimate of ∼90 kJ/mol for low N2 coverages on stoichiometric IrO2(110). The DFT calculations also quantitatively reproduce the observed stabilization of N2 by co-adsorption on-top O-atoms and predict the destabilization of N2 on IrO2(110) as the N2 adlayer becomes crowded at high coverages.

Food safety: a linchpin of One Health.

In 2015, the United Nations General Assembly agreed upon 17 global Sustainable Development Goals. The first of these is: 'End poverty in all its forms everywhere'. The second is to: 'End hunger, achieve food security and improved nutrition, and promote sustainable agriculture'. Food safety is a global priority, since every global citizen has the right to have access to safe and nutritious food. Safe food contributes to people's health and productivity, as well as providing a strong foundation for development and poverty alleviation. Every year, numerous people are affected by foodborne illnesses in developed countries, while widespread illness is even more likely in developing countries. Among society's major concerns are the health risks posed by microbial pathogens and chemicals in food. A One Health approach is crucial to achieving the global goal of food safety and security for all and will improve health outcomes for every citizen.

En 2015, l'Assemblée générale des Nations Unies a adopté les 17 Objectifs de développement durable pour le monde. Le premier de ces objectifs est d'éliminer l'extrême pauvreté partout dans le monde. Le deuxième s'énonce comme suit : « éliminer la faim, assurer la sécurité alimentaire, améliorer la nutrition et promouvoir l'agriculture durable ¼. La sécurité sanitaire des aliments constitue une priorité mondiale, dans la mesure où chaque citoyen doit pouvoir accéder à des aliments sains et nutritifs. Une alimentation saine contribue à la santé et productivité des individus, en plus de fournir une base solide au développement et à la réduction de la pauvreté. Chaque année dans les pays développés, les maladies transmises par les aliments touchent un nombre élevé de personnes tandis que le risque de propagation à grande échelle de ces maladies est encore plus présent dans les pays en développement. Les risques pour la santé liés à la présence d'agents pathogènes et de résidus chimiques dans les aliments figurent parmi les grandes préoccupations de la société d'aujourd'hui. L'approche Une seule santé est indispensable pour atteindre l'objectif mondial d'assurer la sécurité sanitaire des aliments et leur disponibilité pour tous, tout en améliorant l'état de santé de tous les citoyens.

En 2015, la Asamblea General de las Naciones Unidas acordó definir 17 Objetivos de Desarrollo Sostenible de alcance mundial. El primero de ellos reza así: «Poner fin a la pobreza en todas sus formas en todo el mundo¼, y el segundo así: «Poner fin al hambre, lograr la seguridad alimentaria y la mejora de la nutrición y promover la agricultura sostenible¼. La inocuidad de los alimentos es una prioridad de dimensión planetaria, pues todo ciudadano del mundo tiene derecho a disfrutar de una alimentación segura y nutritiva. La inocuidad de los alimentos contribuye a la salud y productividad de las personas, además de sentar sólidas bases para el desarrollo y la reducción de la pobreza. Cada año, muchas personas padecen enfermedades de transmisión alimentaria en países desarrollados, mientras que en los países en desarrollo es incluso más probable la extensión generalizada de esas patologías. Entre las grandes preocupaciones de la sociedad están los riesgos para la salud que derivan de la presencia en los alimentos de patógenos microbianos y productos químicos. El hecho de trabajar en clave de Una sola salud, indispensable para cumplir el objetivo mundial de garantizar a todos la inocuidad de los alimentos y la seguridad alimentaria, también redundará en mejores resultados sanitarios para todos y cada uno de los ciudadanos.

Nipah virus infection: A review.

Nipah virus (NiV) is an emerging bat-borne pathogen. It was first identified 20 years ago in Malaysia and has since caused outbreaks in other parts of South and Southeast Asia. It causes severe neurological and respiratory disease which is highly lethal. It is highly infectious and spreads in the community through infected animals or other infected people. Different strains of the virus show differing clinical and epidemiological features. Rapid diagnosis and implementation of infection control measures are essential to contain outbreaks. A number of serological and molecular diagnostic techniques have been developed for diagnosis and surveillance. Difficulties in diagnosis and management arise when a new area is affected. The high mortality associated with infection and the possibility of spread to new areas has underscored the need for effective management and control. However, no effective treatment or prophylaxis is readily available, though several approaches show promise. Given the common chains of transmission from bats to humans, a One Health approach is necessary for the prevention and control of NiV infection.

Serum cortisol level and survival rate of juvenile Epinephelus fuscoguttatus following exposure to different salinities.

BACKGROUND AND AIM: Brown-marbled grouper Epinephelus fuscoguttatus is a premium marine food fish with high demand in Asia. In fish, stress due to environmental changes such as fluctuations in the salinity can result in increased cortisol level. Stress in fish increases susceptibility to diseases ultimately resulting in death. Therefore, the aim of this study was to investigate the salinity tolerance of E. fuscoguttatus and their survival in lower salinities. MATERIALS AND METHODS: In this study, grouper juveniles (92.43±standard error of the mean 0.51 mm) maintained in 31 ppt seawater were transferred into five tanks with seawater diluted to 25, 20, 15, 10, and 5 ppt. The salinity of the control group was not changed and was maintained at 31 ppt. Serum cortisol was measured using ELISA at 0, 30, 60, and 120 min after the fish were transferred to the different concentrations of salinity. RESULTS: The survival percentage was recorded for 14 days following the transfer and the results revealed that serum cortisol of fish in a high change in salinity (15, 10, and 5 ppt) was significantly higher than the control group immediately after exposure. At the high salinity change, the cortisol levels gradually decrease at 30 min and 60 min, until no difference in cortisol concentration was observed at 120 min. No mortality was observed in fish exposed to low salinity change (25 and 20 ppt) while in higher salinity change (5 ppt), the survival percentage was 50%. CONCLUSION: The study revealed that the serum cortisol concentration was high initially and continues to decrease to resting cortisol level at 120 min indicating that cortisol hormone is released following acute stress as a primary response in grouper juveniles.

Phenolic content and antioxidant activity of Tetraselmis tetrathele (West) Butcher 1959 cultured in annular photobioreactor.

Tetraselmis tetrathele (West) Butcher is an important microalgae due to its high antioxidant content and other bioactive compounds such as flavonoids and polyphenols. Therefore, it has potential as a suitable raw ingredient for various product developments in aquaculture, food and nutraceutical industries. The antioxidant activity of T. tetrathele (UPMC-A0007) was determined by culturing in f/2 and Conway media for 56 days in 120 l annular photobioreactors. The total phenolic (TPC) and antioxidant contents of T. tetrathele were determined six times during different phases of the culture period. The antioxidant activities of T. tetrathele's crude extract were determined by diphenylpicrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays. Two groups of cells based on size; small sized-cells (3.0-5.0?10-11g cell(-1)) and big sized-cells (5.5-8.0?10(-11) g cell(-1)) were observed in the f/2 media. Small sized-group showed 1.6 times higher total phenolic content (2.99?0.14 mg GAEg(-1)) than big sized-cells. These results suggest that T. tetrathele is a potential antioxidant source and effective antioxidant production can be achieved by controlling the cell size in their culturing process.

Enhancement of lipid production in two marine microalgae under different levels of nitrogen and phosphorus deficiency.

Microalgae are important food sources for aquaculture animals. Among the different factors which influence the biochemical composition of microalgae, nitrogen and phosphorus are two of the most important nutrient sources for growth and development. The present study aimed to assess the effects of nitrogen and phosphorus deficiency on lipid production of Chlorella sp. and Chaetoceros calcitrans. Early stationary phase culture of these species were exposed to different stress levels of nitrogen and phosphorus (25%, 50% and 75% of the full NO(3)-N and PO(4)-P concentration in the Conway media), and solvent extraction and gas-liquid chromatography methods were performed for analysis of lipid and fatty acid composition. The results revealed that lipid production in these two species significantly increased (P<0.05) as nitrogen and phosphorus decreased. The fatty acid proportion remained unaffected under nitrogen deficiency, while phosphorus limitation resulted in a decrease of saturated fatty acids and promoted a higher content of omega-3 fatty acids in these species. The protein and carbohydrate levels were also altered under limited nutrients. Therefore, these conditions could be used for enhanced lipid production in microalgae for aquaculture and other industrial applications.

Sustainable aquaculture of Asian arowana--a review.

Asian arowana, Scleropages formosus is a highly valued aquarium fish in the world, particularly in Asian countries, and has been listed as one of the most highly endangered species. This is a freshwater, carnivorous, fairly large mouth breeding fish belonging to the family Osteoglossidae. Arowana can be found in different colour varieties such as green, red, silver and golden. Among these varieties, Malaysian golden is the most valuable fish and is endemic to the Krian riverine system, Malaysia. However, overexploitation, habitat change and pollution have caused a serious decline of this arowana variety. Recently, arowana aquaculture industry is expanding rapidly in Southeast Asian countries. However, difficulties in an accurate differentiation of sex and strains, causing imbalanced stocking ratios for optimum spawning, remain major obstacles in maximizing arowana production. In addition, problems in sustainable water sources of suitable quality and prevention of diseases need to be addressed. Recirculating aquaculture system (RAS) and bioremediation are two possible technologies that could be used to minimize pollution and ensure adequate high-quality water for arowana culture. In addition, the application of appropriate molecular markers for sex and strain identification is also an important strategy required for the improvement of captive breeding. This review discusses several issues such as the importance of arowana as an aquarium fish, its market demand, current problems in the arowana aquaculture industry and the possible technologies to enhance reproductive capacity and increase culture production. ?

Microalgae as sustainable renewable energy feedstock for biofuel production.

The world energy crisis and increased greenhouse gas emissions have driven the search for alternative and environmentally friendly renewable energy sources. According to life cycle analysis, microalgae biofuel is identified as one of the major renewable energy sources for sustainable development, with potential to replace the fossil-based fuels. Microalgae biofuel was devoid of the major drawbacks associated with oil crops and lignocelluloses-based biofuels. Algae-based biofuels are technically and economically viable and cost competitive, require no additional lands, require minimal water use, and mitigate atmospheric CO2. However, commercial production of microalgae biodiesel is still not feasible due to the low biomass concentration and costly downstream processes. The viability of microalgae biodiesel production can be achieved by designing advanced photobioreactors, developing low cost technologies for biomass harvesting, drying, and oil extraction. Commercial production can also be accomplished by improving the genetic engineering strategies to control environmental stress conditions and by engineering metabolic pathways for high lipid production. In addition, new emerging technologies such as algal-bacterial interactions for enhancement of microalgae growth and lipid production are also explored. This review focuses mainly on the problems encountered in the commercial production of microalgae biofuels and the possible techniques to overcome these difficulties.

Microvolt T-wave alternans in patients undergoing elective coronary artery bypass grafting: a pilot study.

INTRODUCTION: We designed a prospective observational study targeting a selective population of patients undergoing elective coronary artery bypass grafting with normal systolic function. In this study we looked at the prevalence of pre-operative microvolt T-wave alternans and if it predicts atrial fibrillation after surgery. METHODS: The inclusion criteria included all patients referred to the cardiothoracic outpatient clinic for elective bypass, who can perform aerobic exercise, with a recent exercise stress test exercising at least to 85% of the maximal predicted heart rate (220 - age) and with non-limiting chest pain at maximal exercise. Twenty patients met the inclusion/exclusion criteria between May 2008 and February 2010. The hospital course of those patients was followed, and in-hospital events were recorded. RESULTS: Nine out twenty (45%) of patients had a non-negative microvolt T-wave alternans tracing. Six patients (30%) developed new onset atrial fibrillation post surgery. Patients with non-negative microvolt level T-wave alternans are more likely to develop atrial fibrillation post coronary artery bypass grafting then patients with negative microvolt level T-wave alternans (p=0.05). CONCLUSIONS: This pilot study provides the first clinical evidence that patients with ischemic heart disease and normal systolic function have a high prevalence of abnormal microvolt T-wave alternans and might be at higher risk of sudden cardiac death. In addition our results show that microvolt level T-wave alternans predicts post coronary artery bypass grafting new onset atrial fibrillation.

Fluorescence imaging for the detection of early neoplasia in Barrett's esophagus: old looks or new vision?

Early neoplasia arising from Barrett's esophagus is often small, focally distributed and endoscopically poorly visible, and random four-quandrant biopsies may easily miss early lesions. Advanced imaging techniques, such as (auto)fluorescence-based modalities, aim to increase the detection rate of early lesions or the yield of random biopsies. Fluorescence-based light-tissue interaction has been designed successfully in point-probe differentiating spectroscopy systems or integrated into wide-field endoscopic systems such as autofluorescence imaging (AFI). In this review, we discuss the most recent advances in fluorescence spectroscopy and imaging for detecting early Barrett's neoplasia. A spectroscopy probe, integrated into regular biopsy forceps, was shown to offer decent discriminatory capabilities, while ensuring spot-on correlation between the measured area and the corresponding histology. With this tool, surveillance endoscopy with random biopsies may become more efficient and sensitive. AFI was shown to increase the targeted detection of early neoplasia. However, random biopsies could compensate for this effect. The clinical impact of AFI on the diagnosis and the treatment of early neoplasia is limited, and yet AFI may offer a novel approach in biomarker-based risk-stratification models. Moreover, in combination with new, readily available contrast agents such as fluorescent lectins, fluorescence imaging may receive renewed interest.

Endoscopic TriModal imaging and biomarkers for neoplasia conjoined: a feasibility study in Barrett's esophagus.

In Barrett's esophagus (BE), the normal squamous lining of the esophagus is replaced by specialized columnar epithelium. Endoscopic surveillance with autofluorescence imaging (AFI) and molecular biomarkers have been studied separately to detect early neoplasia (EN) in BE. The combination of advanced-imaging modalities and biomarkers has not been investigated; AFI may help detecting biomarkers as a risk-stratification tool. We retrospectively evaluated a cohort of patients undergoing endoscopy for EN in BE with AFI and correlated five biomarkers (HPP1, RUNX3, p16, cyclin A, and p53) in tissue samples with AFI and dysplasia status. Fifty-eight samples from a previous prospective study were selected: 15 true-positive (TP: AFI-positive, EN), 21 false-positive (FP: AFI-positive, no EN), 12 true-negative (TN1; AFI-negative, no EN in sample), 10 true-negative (TN2: AFI-negative, no EN in esophagus). Methylation-specific RT-PCR was performed for HPP1, RUNX3, p16, and immunohistochemistry for cyclin A, p53. P < 0.05 was considered statistically significant. Bonferroni correction was used for multiple comparisons. P16, cyclin A, p53 correlated with dysplasia (P < 0.01, P = 0.003, P < 0.001, respectively). Increased p16 methylation was observed between TP versus TN2 (P = 0.003) and TN1 versus TN2 (P = 0.04) subgroups, suggesting a field defect. Only p53 correlated with AFI-status (P = 0.003). After exclusion of EN samples, significance was lost. Although correlation with dysplasia status was confirmed for p16, cyclin A and p53, underlining the importance of these biomarkers as an early event in neoplastic progression, none of the investigated biomarkers correlated with AFI status. A larger prospective study is needed to assess the combination of AFI and a larger panel of biomarkers to improve risk stratification in BE.