Transferability of global retention models in reversed-phase liquid chromatography for natural products.

Considerable progress has been made in enhancing resolution in reversed-phase liquid chromatography for the analysis of complex samples, particularly within the field of natural products, through the application of global retention models using multi-linear gradients. Global models effectively differentiate solute retention effects from those originating from the column and solvent, offering predictive capabilities comparable to conventional individual retention models, without the requirement for standards for all compounds. While conventional individual models result in higher accuracy, they frequently demand standards that are unavailable for natural product samples. Moreover, the creation of individual models can be time-consuming due to the need for repetitive work for additional compounds. Experimental validation of global models has demonstrated that the accuracy is enough for the prediction of complex chromatograms. Through a carefully designed experimental work, this study reports the correct determination of global parameters for column and solvent, with excellent consistency across various medicinal plant samples. The successful transfer of predictions and optimisation of resolution across diverse plant species (lemon balm, peppermint, and pennyroyal) is confirmed. This highlights the applicability of predictions using global models across botanical varieties.

Performance of global retention models in the optimisation of the liquid chromatographic separation (II): Complex multi-analyte samples.

BACKGROUND: Enhancing the quality control of medicinal plants is a complex challenge due to their rich variety of chemical compounds present at varying and extreme concentrations. Chromatographic fingerprints, which have become essential for characterising these complex natural materials, require achieving optimal separation conditions to effectively maximise the number of detected peaks. The challenges in optimising fingerprints and other complex multi-analyte samples include the unavailability of standards, the presence of unknown constituents and the substantial workload that would require conventional optimisation methods based on models. RESULTS: This work introduces an interpretive optimisation approach which operates on the premise of predicting chromatograms using global models. Initially, a multi-linear gradient experimental design is sequentially executed to accommodate all peaks in the chromatogram in an adequate time window. Following this, a small set of sample peaks (reference peaks) is selected based on their consistent traceability across all chromatograms in the design. Using this reference dataset, a global model is constructed, initially focused solely on the reference peaks and later extended to encompass all detected peaks in the sample. The aim is to find gradients that maximise resolution while minimising analysis time. These optimised gradients are applied successfully to enhance the separation of medicinal plant extracts, with particular emphasis on peppermint and pennyroyal extracts. SIGNIFICANCE: The proposed optimisation relying on global models can be applied to highly complex samples even in the absence of standards, or in cases where standards are available but their use is impractical due to workload constraints. Moreover, in discerning the most promising gradients for highly complex samples, peak purity has demonstrated superior reliability and competitiveness compared to peak capacity as chromatographic objective function.

Analysis and classification of tea varieties using high-performance liquid chromatography and global retention models.

As a result of their metabolic processes, medicinal plants produce bioactive molecules with significant implications for human health, used directly for treatment or for pharmaceutical development. Chromatographic fingerprints with solvent gradients authenticate and categorise medicinal plants by capturing chemical diversity. This work focuses on optimising tea sample analysis in HPLC, using a model-based approach without requiring standards. Predicting the gradient profile effects on full signals was the basis to identify optimal separation conditions. Global models characterised retention and bandwidth for 14 peaks in the chromatograms across varied elution conditions, facilitating resolution optimisation of 63 peaks, covering 99.95 % of total peak area. The identified optimal gradient was applied to classify 40 samples representing six tea varieties. Matrices of baseline-corrected signals, elution bands, and band ratios, were evaluated to select the best dataset. Principal Component Analysis (PCA), k-means clustering, and Partial Least Squares-Discriminant Analysis (PLS-DA) assessed classification feasibility. Classification limitations were found reasonable due to tea processing complexities, involving drying and fermentation influenced by environmental conditions.

Performance of global retention models in the optimisation of the chromatographic separation (I): Simple multi-analyte samples.

Conventional retention models lead to accurate descriptions of the elution behaviour from the fitting of data for single solutes or from a set of solutes, one by one. However, the simultaneous fitting of several solutes through a regression process that separates the contributions of column and solvent from those of each solute is also possible. The result is a global retention model constituted by a set of equations with some common parameters (those associated with column and solvent), whereas others, specific to each solute, differ for each equation. This work explores the possibilities, advantages, and limitations of global models when they are applied to the optimisation of chromatographic resolution. A set constituted by 13 drugs (diuretics and ß-blockers) and a training experimental design of seven multi-linear gradients are considered. Since standards for all compounds were available, the optimisation based on global models could be compared with the conventional optimisation, which is based on individual models. In their current state, global models do not predict changes in elution order, but they do allow for incorporating additional solutes (e.g., new analytes or matrix peaks) with only one new experiment. This possibility is explored by extending the model for the 13 analytes to include 26 peaks associated with a contamination in the injector. The combination of individual and global models allows an optimisation where the effects of matrix peaks on the separation of analytes can be integrated.

Counselling toward reducing alcohol use, knowledge about its morbidity and personal consumption among students of medical and dental courses in north-western Spain.

BACKGROUND: Alcohol use disorder (AUD) is directly linked to high-risk consumption. Healthcare students have a crucial role to play in its prevention and management. The aim of this study is to analyse alcohol consumption, as well as to consider the knowledge and attitudes regarding morbidity, and the stage of change when providing assistance to quit AUD. MATERIAL AND METHODS: A cross-sectional study was conducted among Dentistry and Medical students using specific and validated questionnaires in an anonymous and voluntary way. Initially, 925 students were invited to participate, of them 500 were reached. RESULTS: Among them 85.9% suffered from AUD of whom 75% were women (p<0.001), and it was considered that the female gender constituted an independent risk factor (OR=2.63, CI 95% 1.55-4.45, p<0.001). The majority of the participants did not achieve the pass mark, nonetheless, the results showed improved levels of knowledge among participants in the latter years of their studies (p<0.001). Dental students demonstrated greater shortcomings in terms of their knowledge of general pathology, whereas the medical students' knowledge of oral pathologies proved worse (p<0.001). Most of students believed that identifying cases of AUD-affected patients falls within their competence, nonetheless, they believed that they do not have the necessary competencies. Among participants 58.2% were in a stage of change regarding AUD attitudes. CONCLUSIONS: The majority of respondents presented AUD. In general, the participants' knowledge about alcohol was low. Reviewing the syllabuses and evaluating the implementation of gender-differentiated training programmes in both degrees would be considered necessary.

Leishmaniasis cutánea simuladora de pericondritis

Resumen La leishmaniasis cutánea presenta una clínica muy característica de pápula eritemato-amarillenta con costra central, en regiones expuestas, que los profesionales de la salud podemos identificar y tratar sin necesidad de biopsia. En ocasiones, se presenta con una clínica atípica que puede conducir a un error diagnóstico, con su perpetuación y malestar en el paciente. Presentamos el caso de una mujer de 53 con una placa eritema-to-exudativa por toda la extensión del pabellón auricular izquierdo de varios meses de evolución. Había sido tratada desde el inicio con antibioterapia y corticoides, sin conseguir mejoría y con un claro empeoramiento, al haberse extendido por toda la oreja. Tras la realización de la biopsia, se llegó al diagnóstico de leishmaniasis cutánea erisipeloide. Se procedió a realizar tratamiento dirigido con fluconazol y posteriores infiltraciones de antimoniato de meglumina consiguiendo su completa resolución.

Abstract Cutaneous leishmaniasis presents a very characteristic clinic of erythematous-yellowish papule with central crust, in exposed regions, that we health professionals can identify and treat without the need for a biopsy. Sometimes, it presents with an atypical clinic that can lead to a diagnostic error, with its perpetuation and discomfort in the patient. We present the case of a 53-year-old woman with an erythematous-exudative plaque throughout the extension of the left atrial pavilion of several months of evolution. It had been treated from the start with antiobiotherapy and corticosteroids, without achieving improvement and with a clear worsening, as it had spread throughout the ear. After the biopsy was performed, the diagnosis of erysipeloid cutaneous leishmaniasis was reached. Directed treatment with fluconazole and subsequent infiltrations of meglumine antimoniate were made, achieving its complete resolution.

Association between xerostomia, oral and general health, and obesity in adults. A cross-sectional pilot study.

BACKGROUND: The objective of this study was to analyse the association between oral and general health variables and obesity indicators with the sensation of dry mouth or xerostomia as evaluated on the Xerostomia Inventory (XI). MATERIAL AND METHODS: A total of 354 randomly selected subjects participated in this cross-sectional pilot study and completed an anonymous questionnaire. Anthropometric, clinical, and xerostomic variables were evaluated. Kruskal-Wallis, ANOVA and Bonferroni test were used for multiple comparisons. ROC curves and multinomial logistic regression were used to determine the (OR) risk of xerostomia. RESULTS: A total of 30.7 % of respondents reported xerostomia based on XI. The dry mouth question, the XI taken as a "gold standard", showed a diagnostic sensitivity of 70.37 %, and a specificity of 83.27 % (AUC=0.768, p<0.001). Logistical regression showed the highest xerostomia OR was associated to patients with bad self-perceived health, 6.31 (CI 95% 2.89-13.80, p<0.001). In the model adjusted for tooth mobility, bone or respiratory diseases, and the consumption of anxiolytics and antidepressants, the OR was 3.46 (CI 95% 1.47-8.18, p=0.005). CONCLUSIONS: a high prevalence of xerostomia was found in this cross-sectional pilot study, which was significantly more frequent in women, and increased with age. Xerostomia was associated to several systemic diseases, psychological conditions, and oral functional disorders such as tooth mobility. These preliminary results can serve as the basis for developing guidelines for the application of innovative measures designed to improve the quality of life of individuals with xerostomia.

Assessment of saliva and oral candidiasis levels 12, 24 and 36 months after radiotherapy in patients with head and neck cancer.

INTRODUCTION: Hyposalivation is a serious complication during radiotherapy (RT) and it is one of the major risk factors for the presence of candidiasis. The aim of this study was to evaluate the salivary hypofunction during the different stages of RT, analysing its connection with the presence of candidiasis. MATERIAL AND METHODS: A retrospective study was performed in 83 patients who had been diagnosed with head and neck tumours and who were undergoing RT treatment. Their salivary function was clinically analysed throughout the course of the RT treatment (before, during and after treatment) by means of the whole saliva test (WST), both unstimulated (WST-I) and stimulated (WST-II), and its relationship with candidiasis was evaluated using culture-based methods. RESULTS: The WST-I before RT was 37.24±17.36mm and the WST-II was 60.70±30.98mm, with 47% of patients testing positive for candidiasis. The prevalence of candidiasis increased up to 55.8% during RT and it returned to similar pre-RT levels at the end of treatment (45.2%). A statistical significant relationship was found between low WST-I and candidiasis in the 1st (13.58 vs 20.78mm), 3rd (18.06 vs 24.36mm), 6th (16.83 vs 24.5) and 12th (16 vs 28.74mm) months after RT; and this relationship was also detected for WST-II in the 1st (24.73 vs 41.26mm) and 3rd (27.71 vs 39.91mm) months after RT. Female sex was identified as an independent associated risk factor for mild hyposalivation before RT (OR=6.50, CI: 95% 1.77-23.93, p=0.005) and glandular hypofunction (OR=3.01, CI: 95% 1.12-8.10, p=0.029). DISCUSSION: There is a clear relation between hyposalivation and the presence of candidiasis during and after RT. Larger studies must be performed in order to further elucidate this effect.

Therapeutic alternatives in the management of osteoradionecrosis of the jaws. Systematic review.

BACKGROUND: to systematically review the literature, comparing the healing of osteoradionecrosis (ORN) among the therapeutic alternatives: surgical, pharmacological and combined. MATERIAL AND METHODS: The review was organized according to the PRISMA protocol with regards to the following PICO question: patients with ORN of the jaws (P=Patient); all interventions reported (I = intervention); between all therapies (C=Comparison); healing of lesions (O=outcome). RESULTS: Surgical treatment was the most common choice (46.3%) followed by pharmacological treatment, exclusively (25.9%) or combined (26.9%). Treatment exclusively by surgical intervention seems to be most effective option, with 51.2% of the lesions healed, OR for healing of 5.7 (CI95% 1.9-16.9, p=0.002). Only 1 case (0.9%) corresponded to low level laser therapy. CONCLUSIONS: It seems clear that early intervention with conservative surgical combined with pharmacological methods improves the prognosis of ORN.

A new morphologic classification of the alveolar ridge after distraction osteogenesis in human patients. A 17 years retrospective case series study.

BACKGROUND: To perform a morphologic classification based on the results of bone augmentation after a distraction osteogenesis. MATERIAL AND METHODS: Thirty-four (34) patients (24 women and 10 men; mean age, 47.1 years (SD=9.5); age range, 23 to 62 years) underwent a total of 42 alveolar ridge distractions before the placement of a total of 89 dental implants. Ridge bone morphology was evaluated as the main ordinal variable. Chi-squared, Kruskal-Wallis and ANOVA one-way test were used. RESULTS: Category I (30.95%): consisted of wide alveolar rim and no bone defects Category II (28.57%): wide alveolar rim, lateral bone surface concavity. Category III (23.81%): narrow alveolar rim, lateral bone surface concavity. Category IV (2.38 %): distraction transport segment forming a bridge, without bone formed beneath and requiring guided bone regeneration. Category V (9.52%): return of the transport segment to its initial position due to the reverse rotation of the distractor screw. Category VI (4.76 %): distraction transport segment completely lost. Subcategory D (28.57%), consisted of lingual deviation of the distraction axis, occurring in any of the categories I to IV. More men (76.9 %) presented with category I (p<0.001). The use of the chisel resulted mainly in categories I and II (69.4 %) (p<0.001). GBR was only required in 23.1 % of the cases in Category I (p=0.011). The bone height achieved decreases as the category increases, due to the accompanying osteogenic limitations (p<0.001). The implants placed in category I were longer 11.5 ± 0.9 mm (CI95% 10.9-11.9 mm) compared to those placed in category III with a length of 10.4 ± 1.5 mm (CI95% 9.5-11.4 mm) (p=0.035). CONCLUSIONS: The alveolar ridge after distraction osteogenesis could be divided into six morphologic categories which provide a useful basis for decision-making regarding implant placement.

Clinicopathological features of peripheral ossifying fibroma in a series of 41 patients.

Peripheral ossifying fibromas are benign mesenchymal lesions that usually arise in the anterior maxilla of young female patients. Histologically they consist of spindle cell proliferation with focal mineralisation. We reviewed 48 specimens from 41 patients and recorded the clinical data, sex, and age of the patients, site and size of the lesions, treatment, and postoperative outcome. Histologically the presence of mature, woven bone, cementum, and calcifications were evaluated and evaluated immunohistochemically. Lesions were more frequent in female patients in the third and fourth decade, and were usually in the lower maxilla and smaller than 2cm. All lesions were conservatively excised, and they relapsed in eight patients. Histopathologically, the lesions were poorly circumscribed, moderately cellular proliferations, with no discernible architectural pattern. All tumours showed some degree of mineralisation, the presence of immature bone being the most common. Immunohistochemical examination showed staining of tumoural cells for smooth muscle actin and CD68. Lesions tended to occur more commonly in female patients, but one decade later than usually reported. We found a higher recurrence rate in lesions that contained cementum-like material but without bone formation, suggesting a lack of maturation in this group. Immunohistochemical results were consistent with myofibroblastic differentiation but they added no information about the behaviour of the lesions.

Management options for low-dose methotrexate-induced oral ulcers: A systematic review.

BACKGROUND: Oral ulcers caused by methotrexate (MTX) at low doses are a known side effect of this drug. Although increasingly more patients are medicated with MTX, these painful ulcers, without traumatic origin and resistant to any type of treatment, are not usually identified by health professionals as a side effect of the medication. MATERIAL AND METHODS: In the absence of a consensus protocol for the effective treatment of oral lesions produced by MTX, the objective of this article was to review and analyse the information from articles related to oral ulcers produced by low-dose MTX and to record the clinical management performed and the MTX dose given to the patient. Data sources - Medline, Web of Science, and Cochrane Library. Participants - Patients treated with low-dose MTX (less than 25 mg/week). Interventions - Management of oral lesions caused by MTX. Study eligibility criterion, study appraisal and synthesis method: An initial search was carried out in the aforementioned databases with the terms 'methotrexate AND oral OR ulcer'. The search was carried out using both medical subject heading (MeSH) terms and a free search between January 2003 and January 2018. Of the results obtained, two independent researchers analysed abstracts that met the search criteria, that is, those that mentioned oral ulcers produced by MTX at low doses. Next, both researchers read the complete article and determined whether it met the following inclusion criteria: written in English, specified the dose of MTX prescribed for the patient and specified the protocol of action for the ulcers. A third investigator acted as a mediator in cases of dispute. Agreement was calculated using Cohen's kappa coefficient, with a k value of 0.82. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guide for systematic reviews was used. RESULTS: The initial search resulted in a total of 66 articles, of which 30 were selected to assess their inclusion in this study. Finally, 16 met the inclusion criteria. Using the Pierson and Newcastle-Ottawa scales and Bradford Hill criteria modified for studies of case series and "in relation to a case", 2 were rated as high quality, 2 were rated as low quality and 12 were rated as medium quality. The limitations of this study are based on the fact that all of the articles available to carry out the systematic review were "in relation to a case or series of cases", with the heterogeneity of data that this implies. CONCLUSIONS: Evidence on the management of oral ulcers in the oral cavity produced by MTX at low doses is scarce due to the heterogeneity of data and the measures adopted in the selected studies. Therefore, it seems that this management is relegated to the perception of the clinician rather than to a specific protocol of action. Studies with a longer follow-up duration and larger sample size are needed to guide different health professionals on the management of these lesions.

Survival study of leukoplakia malignant transformation in a region of northern Spain.

BACKGROUND: Oral leukoplakia is the most common potentially malignant disorder (PMD) of the oral cavity. The objectives of this study are to determine the clinicopathologic features in a group of patients with oral leukoplakia of Northern Spain (Galicia), determining the factors associated to clinical risk and analyzing the malignant transformation of these patients. MATERIAL AND METHODS: We included 85 patients. We recorded sex and age, habits like alcohol and tobacco, size, clinical appearance, site, number of lesions, and presence or absence of dysplasia. We assess the association between risk factors and transformation and developed a logistic regression analysis. Finally we used the Kaplan-Meier and log-rank test for the survival analysis. RESULTS: 7 patients (8.2%) had malignant transformation. The mean follow-up of the patients was 4.13 years versus 5.58 years of those who developed carcinoma. Only location and initial dysplasia have a statistically significant relationship with malignant transformation, but when applied the long rank test only the presence of dysplasia remains statistically significant(P<0,026). Oral Cancer Free Survival was 81.9% (0.150) at 11 years for the group without dysplasia. CONCLUSIONS: We found that the presence of dysplasia is the only risk factor that is statistically related to the development of a carcinoma.

Lifestyles guide and glaucoma (i). Sports and activities. / Guía de estilos de vida y glaucoma (i). Deporte y actividades.

PURPOSES: The increase in quality and life expectancy, often leads to many patients asking the glaucoma specialist whether some sports, activities or hobbies would affect their illness. The aim of this article is to establish guidelines for patients, based on the scientific evidence of published papers. METHODS: Review of all published articles on glaucoma and sports or other activities. The papers were classified according to the level of scientific evidence based on the Oxford Centre for Evidence-Based Medicine classification. RESULTS: Aerobic sports are beneficial for the patient. Yoga indoor sports or relaxation techniques should be avoided if Valsalva manoeuvres are performed or the head is placed very low. Also, the patients must avoid sudden changes in height. Intense heat does not seem to lead to progression of glaucoma, but intense cold can affect patients with vascular dysregulation. Activities using the near vision slightly reduce the intraocular pressure. The use of wind instruments may raise intraocular pressure, depending on the technique used. CONCLUSIONS: Certain sports and activities may have an influence on the onset or progression of glaucoma. Glaucoma specialists should have adequate information about the scientific evidence in the publications, in order to properly advise the patients.

Lifestyles guide and glaucoma (II). Diet, supplements, drugs, sleep, pregnancy, and systemic hypertension. / Guía de estilos de vida y glaucoma (II). Dieta, suplementos, drogas, sueño, embarazo e hipertensión arterial.

PURPOSE: To establish evidence based guidelines to advise patients on the relationship between habits, diet, certain circumstances, diseases and glaucoma. METHODS: Review of all published articles on glaucoma and sports or other activities. The papers were classified according to the level of scientific evidence based on the Oxford Centre for Evidence-based Medicine classification. RESULTS: The evidence on the relationship between diet or supplements and the incidence or progression of glaucoma is insufficient to make a general recommendation for glaucoma patients. Although some studies on normal tension glaucoma suggest that Gingko biloba could reduce glaucoma progression, the results do not allow a general recommendation for all these patients. Similarly, the evidence on the usefulness of vitamin supplements is not conclusive. The studies on smoking do not clearly demonstrate the relationship between this habit and incidence of glaucoma. Marihuana is not a useful treatment for glaucoma. Although the results on the relationship between sleep apnoea and glaucoma are heterogeneous, it is recommended that patients with moderate to intense apnoea are tested for glaucoma. Pregnancy does not influence the course of the disease, but several hypotensive drugs may be harmful for the foetus. Nocturnal systemic hypotension is a risk factor for glaucoma progression. CONCLUSIONS: Certain habits, circumstances, or diseases may have an influence on the onset or progression of glaucoma. It is important to have adequate information about the scientific evidence in the publications in order to properly advise patients.

Desensitization Protocol in Recipients of Deceased Kidney Donor With Donor-Specific Antibody-Low Titers.

BACKGROUND: Kidney transplantation is the better option for end-stage renal disease (ESRD), but for patients with human leukocyte antigen (HLA) sensitization, the wait times are significantly longer than for patients without antibodies. Many desensitization protocols have been described involving strong immunosuppression, the use of apheresis, and B-cell-modulating therapies. We have designed a desensitization protocol from day 0 for deceased donor kidney transplantation. Our aim was to present our initial experience with five kidney transplant patients. METHODS: All patients had a negative complement-dependent cytotoxicity cross-match. The desensitization protocol included five to seven doses of thymoglobulin (1.25 mg/kg) and three sessions of plasmapheresis (PP) within the first week after transplantation, with intravenous immunoglobulin (500 mg/kg) after each PP session and one dose of rituximab on day 8. The presence of donor-specific antibodies (DSA) was analyzed by use of Luminex technology; levels between 1000 and 3000 mean fluorescence intensity were considered for desensitization. RESULTS: The median age was 44 years and median renal replacement therapy time was 9 years. All recipients presented 1 to 3 DSA specificities. There were no severe side effects related to PP, infusion of intravenous immunoglobulin, or rituximab. The median follow-up period was 19.3 months. Median serum creatinine level at last follow-up was 1.7 mg/dL. A kidney biopsy was performed in all patients. Graft and patient survival was 100%. CONCLUSIONS: Until now, few data are available concerning whether HLA-incompatible kidney transplantation after desensitization would benefit patients with ERSD. The desensitization strategy using the combination of PP, low doses of intravenous immunoglobulin, and rituximab at our center resulted in a satisfactory clinical outcome.

Acquired night blindness due to bad eating patterns.

We report a case of acquired night blindness in a developed country (Spain) without risk factors for nutritional deficiency disease or family history of hereditary retinal disease. A 76-year-old woman presented with acquired night blindness of 6-month progression. After a thorough inquiry about eating patterns she becomes suspicious of vitamin A low dietary intake, which is analytically confirmed and successfully treated. Despite being very uncommon in our environment and even more in patients without digestive problems, in a patient reporting acquired night blindness vitamin A deficiency should not be discarded until eating patterns have been investigated. It might be especially relevant in certain socioeconomic situations and eating disorders such as bulimia or anorexia nervosa.

The use of CA-IX as a diagnostic method for oral leukoplakia.

The presence and degree of dysplasia are important diagnostic and prognostic criteria for oral leukoplakia, but evaluation of dysplasia is difficult and subjective. Carbonic anhydrase-IX (CA-IX) is expressed primarily in tumor cells and is considered a specific hypoxia marker. We investigated the role of CA-IX in oral leukoplakia. We investigated 30 specimens of oral leukoplakia and 35 dysplasia specimens adjacent to the tumor margin. We analyzed clinical variables including age, sex, degree of dysplasia, and smoking, clinical appearance of leukoplakia, number of lesions, location, size, clinical monitoring, malignant transformation and recurrence. For the immunohistochemical study, we used a noncommercial monoclonal antibody against human CA-IX MAb M75. We found greater CA-IX positivity in nonsmokers, erythroplakia and mottled leukoplakia, those located on the tongue, patients with multiple lesions, 2-4 cm leukoplakias and in recurrent cases, although differences were not statistically significant. All lesions in all samples without dysplasia were negative for CA-IX; however, for all other categories of dysplasia, the percentages of positivity and negativity varied. Regarding the diagnostic index values, we found a sensitivity of 32%, specificity of 100%, a positive predictive value of 100% and a negative predictive value of 13%. Leukoplakias appear mainly in females and potentially are malignant; more than 90% have some degree of dysplasia, and therefore require close clinical and histopathological monitoring. The CA-IX immunohistochemical marker may be useful for screening samples without dysplasia owing to its high specificity.

Quantitative determination of c-myc facilitates the assessment of prognosis of OSCC patients.

Myc genes are a family of proto-oncogenes whose proteins are implicated in the regulation of cell proliferation, differentiation and apoptosis, and in regulating the activity of genes involved in cell division. The aim of the present study was to establish a quantitative description of the expression of c-myc and evaluate its relationship with other clinical and prognostic factors, as well as to establish a multivariate survival prediction model. This is a retrospective study of 68 patients diagnosed with oral squamous cell carcinoma (OSCC). We constructed a tissue microarray for investigating the expression of c-myc by immunohistochemistry. Statistical analyses were carried out, and a multivariate model that predicts survival was established. The average expression of c-myc was 50.32 (SD, 26.05) with a range from 6.60 to 99.48; similar for initial and advanced tumor stages. Non-smoking patients had higher levels of c-myc, showing statistically significant differences (Kruskal-Wallis χ2=5.975; p=0.05). We found no statistically significant relationship between the quantitative expression of c-myc and any other clinical or pathological parameters. For each unit of increase of c-myc, the risk increased by 1.15 (p<0.001; HR, 1.150; 95% CI, 1062-1245). Further study of this protein, which may have a significant diagnostic, prognostic and therapeutic value is warranted. Its determination can be valuable when used together with other markers to assess the prognosis of OSCC patients.

Accuracy and interrater reliability for the diagnosis of Barrett's neoplasia among users of a novel, portable high-resolution microendoscope.

The high-resolution microendoscope (HRME) is a novel imaging modality that may be useful in the surveillance of Barrett's esophagus in low-resource or community-based settings. In order to assess accuracy and interrater reliability of microendoscopists in identifying Barrett's-associated neoplasia using HRME images, we recruited 20 gastroenterologists with no microendoscopic experience and three expert microendoscopists in a large academic hospital in New York City to interpret HRME images. They prospectively reviewed 40 HRME images from 28 consecutive patients undergoing surveillance for metaplasia and low-grade dysplasia and/or evaluation for high-grade dysplasia or cancer. Images were reviewed in a blinded fashion, after a 4-minute training with 11 representative images. All imaged sites were biopsied and interpreted by an expert pathologist. Sensitivity of all endoscopists for identification of high-grade dysplasia or cancer was 0.90 (95% confidence interval [CI]: 0.88-0.92) and specificity was 0.82 (95% CI: 0.79-0.85). Positive and negative predictive values were 0.72 (95% CI: 0.68-0.77) and 0.94 (95% CI: 0.92-0.96), respectively. No significant differences in accuracy were observed between experts and novices (0.90 vs. 0.84). The kappa statistic for all raters was 0.56 (95% CI: 0.54-0.58), and the difference between groups was not significant (0.64 vs. 0.55). These data suggest that gastroenterologists can diagnose Barrett's-related neoplasia on HRME images with high sensitivity and specificity, without the aid of prior microendoscopy experience.