Comparative clinicopathological study of the main anatomic locations of oral squamous cell carcinoma.

OBJECTIVE: To analyze the clinicopathological and evolutionary profile of the main locations of oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: This is a retrospective study on 133 patients treated for OSCC. The group was composed of 48 women and 85 men, with a mean age 63.9 ± 12.73 years. Most cases involved the lingual border of tongue (63), followed by the gingiva (36) and the floor of mouth (34). A comparative analysis was performed using multinomial regression. RESULTS: There were significant differences regarding age, sex, tobacco and alcohol consumption, liver pathology, oral potentially malignant disorders, and bone and perineural invasion. In multivariate regression, tobacco consumption, and bone invasion remained significant. There were no significant differences in relation to prognosis. CONCLUSION: The location of OSCC is an important factor in the clinicopathological assessment of this neoplasm. The main locations of OSCC show differential etiopathogenic and clinicopathological aspects. Tobacco consumption has a great relevance in the floor of mouth; nonetheless, it is less important in the tongue border and the gum, which suggests other pathogenic factors. It is necessary to consider the anatomical location of OSCC in preventive protocols, with the aim of reducing its high mortality.

Clinical practice guideline of the spanish society of oral surgery for oral surgery in patients with coagulation disorders / Guía de práctica clínica de la sociedad española de cirugía bucal para cirugía oral en pacientes con trastornos de la coagulación

Background: The number of patients treated with coagulation disorders, and more specifically with anticoagulanttherapy, has increased worldwide in recent years due to increased life expectancy in developed countries. Theprotocols for managing this type of patient in oral surgery has varied over recent years, especially after the appear-ance of new direct-acting oral anticoagulants (DOACs). The assessment of risk of bleeding in this type of patientwhen undergoing a surgical procedure continues to be a controversial issue for patients, dentists and general prac-titioners. The objective of this document is to offer recommendations, based on evidence, for decision making forpatients with coagulopathies who require dental surgical intervention. Material and Methods: Based on the indications of the “Preparation of Clinical Practice guidelines in the NationalHealth System. Methodological manual”, we gathered a group of experts who agreed on 15 PICO questions basedon managing patients with coagulation disorders in dental surgical procedures, such as fitting of implants or dentalextractions.Results: The 15 PICO questions were answered based on the available evidence, being limited in most cases due tothe lack of a control group. Two of the PICO questions were answered by the experts with a grade C recommendation,while the rest were answered with grade D.Conclusions: The results of this review highlight the need to undertake well designed clinical trials with controlgroups and with a representative sample size.(AU)

Clinical practice guideline of the spanish society of oral surgery for oral surgery in patients with coagulation disorders.

BACKGROUND: The number of patients treated with coagulation disorders, and more specifically with anticoagulant therapy, has increased worldwide in recent years due to increased life expectancy in developed countries. The protocols for managing this type of patient in oral surgery has varied over recent years, especially after the appearance of new direct-acting oral anticoagulants (DOACs). The assessment of risk of bleeding in this type of patient when undergoing a surgical procedure continues to be a controversial issue for patients, dentists and general practitioners. The objective of this document is to offer recommendations, based on evidence, for decision making for patients with coagulopathies who require dental surgical intervention. MATERIAL AND METHODS: Based on the indications of the "Preparation of Clinical Practice guidelines in the National Health System. Methodological manual", we gathered a group of experts who agreed on 15 PICO questions based on managing patients with coagulation disorders in dental surgical procedures, such as fitting of implants or dental extractions. RESULTS: The 15 PICO questions were answered based on the available evidence, being limited in most cases due to the lack of a control group. Two of the PICO questions were answered by the experts with a grade C recommendation, while the rest were answered with grade D. CONCLUSIONS: The results of this review highlight the need to undertake well designed clinical trials with control groups and with a representative sample size.

Photobiomodulation in dental implant stability and post-surgical healing and inflammation. A randomised double-blind study.

BACKGROUND: The aim of this randomized clinical trial was to evaluate the effect of diode laser photobiomodulation (PBM) on post-surgical healing, inflammation and implant stability. METHODS: Forty dental implants were inserted into 13 patients. The implants were randomly divided into two groups. The test group (PBM+) underwent two sessions of PBM (combined diode laser of 630 and 808 nm), the first of which after surgery, and the second, 7 days after the surgical procedure. The control group (PBM-) received simulated laser treatment. The implant stability quotient (ISQ) was determined immediately after the surgical procedure, and 7 days, 4 and 8 weeks later. Post-surgical inflammation was assessed following the criteria described by Bloemen and Cols. Healing was calculated using the healing index (HI). RESULTS: No differences were found in terms of the mean values of implant stability between the test and control groups over time. Only two of the implants (18.2%) from the PBM- group were classified with the maximum healing index (HI = 5), whereas in the PBM+ group, nine implants (45%) were classified with the aforementioned index (P < 0.0001). Using the logistic regression, it was determined that the non-application of the laser in the PBM- group caused an OR of 4.333 times of presenting inflammation (IC95% 1.150-16.323; P = 0.030). CONCLUSIONS: The application of 808 nm infra-red laser for bone tissue, and 630 nm for mucosal tissue in two sessions is considered to be an effective way of reducing inflammation and improving early healing. More studies are needed to confirm these results.

Drug use, risk perceptions and attitudes towards drug use amongst medical and dentistry students.

AIMS: To analyse the use of psychoactive substances and the risk perceptions amongst odontology and medical students. To study their perceptions, attitudes and knowledge, and to evaluate their motivation when helping their patients to stop using these substances. METHODS: A cross-sectional study was conducted amongst 962 students in Spain, using validated questionnaires on an anonymous basis. RESULTS: Amongst these students, drug use varies and increases with age as assessed by the DAST and CAST tests, with more problematic use being observed as the academic cycle progresses (p < .001). Participants in the 2nd cycle presented higher consumption than those in the 1st cycle, in the univariate model (OR = 1.77, IC 95% 1.27-2.48, p = .001) and in the adjusted model (OR = 1.86, IC 95% 1.32-2.62, p < .001). Regarding CAST, non-problematic use in the 1st cycle versus the 3rd cycle presented an OR = 8.69 (IC 95% 4.50-16.78, p < .001) and for low risk use it presented an OR = 15.18 (IC 95% 1.83-14.68). Only 46.7% considered using marijuana on a regular basis as a high risk, whilst 60.5% stated that smoking a pack of cigarettes represents a high risk. Alcohol was the substance for which the risk perception was lowest. 66.2% are in the maintenance stage "I provide my regular drug-using patients help to give up," with women being more likely to be in this stage (p = .012). CONCLUSIONS: High risk of drug use increases after the 1st cycle in Dentistry and in Medicine. Training programmes should be implemented in both degrees, focusing on the 1st years in order to simultaneously prevent drug use amongst students.

Importance of the vaporization margin during CO2 laser treatment of oral leukoplakia: A survival study.

OBJECTIVES: The main purpose of this study was to assess the response of oral leukoplakia to CO2 laser vaporization treatment, as well as determining possible factors that may affect recurrence of lesions. MATERIALS AND METHODS: A retrospective study was conducted, in which the medical records of patients who had been clinically and histologically diagnosed with oral leukoplakia and treated with CO2 laser between 1996 and 2019 at the Oral Medicine Teaching Unit of the Faculty of Dentistry of the University of Santiago de Compostela were reviewed. RESULTS: Fifty-eight patients were included: 36 female and 22 male subjects, with a mean age of 63.7 years old (SD ±13.1). The average follow-up time was 57.5 months (SD ±57.9). A relapse rate of 52.6% was determined. Of all the studied variables, the margin was the only one for which a statistically significant association with recurrence of lesions was demonstrated (p < 0.05). CONCLUSION: The vaporization of lesions using CO2 laser with a safety margin of at least 3 mm from the clinical limits of OL is a key factor in preventing recurrence.

Impact of abutment geometry on early implant marginal bone loss. A double-blind, randomized, 6-month clinical trial.

OBJECTIVES: The objective of this study was to analyze the impact of the abutment width on early marginal bone loss (MBL). MATERIAL AND METHODS: A balanced, randomized, double-blind clinical trial with two parallel experimental arms was conducted without a control group. The arms were "cylindrical" abutment and "concave" abutment. Eighty hexagonal internal connection implants, each with a diameter of 4 × 10 mm, were placed in healed mature bone. The main variable was the peri-implant tissue stability, which was measured as MBL at 8 weeks and 6 months. RESULTS: The final sample consisted of 77 implants that were placed in 25 patients. 38 (49.4%) were placed using the cylindrical abutment, and the other 39 (50.6%) were placed using the concave abutment. The early global MBL of -0.6 ± 0.7 mm in the cylindrical abutment group was significantly higher than it was in the concave abutment group, in which the early global MBL was -0.4 ± 0.6 mm (p = .030). The estimated effect size (ES) was negative for the cylindrical abutment (ES = -1.3730, CI -2.5919 to -0.1327; t-value = -2.4893; p = .0139), therefore implying a loss of mean bone level, and it was positive for the concave abutment (ES = 2.8231; CI: 1.4379 to 4.2083; t-value = 4.0957; p = .0002), therefore implying an increase in the average bone level. CONCLUSIONS: The concave abutments presented significantly less early MBL at 6 months post-loading than classical cylindrical abutments did.

Influence of loading and drilling on marginal bone loss around implants with a Dynamic Bone Management design: A single-blind, randomised, 12-month clinical trial.

PURPOSE: To evaluate marginal bone loss 6 and 12 months after prosthetic loading of implants with Dynamic Bone Management (Straumann, Basel, Switzerland) through the implementation of different drilling protocols. MATERIALS AND METHODS: A balanced, randomised, single-blind clinical trial was conducted with four parallel experimental arms: immediate loading and under-drilling, immediate loading and complete drilling, early loading and under-drilling, and early loading and complete drilling. Forty-four implants with a Dynamic Bone Management design and with a diameter of 3.75 mm and a length of 10.00 mm were placed in healed mature bone (more than 6 months post-extraction). RESULTS: The mean primary stability achieved was 60.6 ± 12.2 implant stability quotient, with a range from 21 to 75, and no differences were observed when considering the drilling protocol used, bone type or location. Early loading resulted in a loss of 0.728 mm (standard error 0.212; 95% confidence interval 1.134 to -0.325; t value -3.440), whereas immediate loading did not result in any bone loss. When the interaction between the loading and drilling protocols was studied, performing the complete drilling protocol in conjunction with early implant loading was found to result in lower marginal bone loss, with a marginal bone gain effect of 0.814 mm (standard error 0.283; 95% confidence interval -0.274 to 1.353; t value 2.880). CONCLUSIONS: Use of the complete drilling protocol in conjunction with early implant loading resulted in the lowest marginal bone loss at 12 months.

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.(AU)

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.

Analysis of the Efficiency and Prognostic Value of the Sentinel Node Technique in Oral Squamous Cell Carcinoma after Seven Years.

Background and objectives: The purpose of this study was to analyse the diagnostic and prognostic efficiency of the sentinel lymph node biopsy technique (SLNB). Materials and Methods: This is a prospective observational study performed by the Hospital Complex in Santiago de Compostela (CHUS) in Spain, between February 2013 and June 2020. The study included 60 patients, who had been diagnosed with OSCC in stage T1/T2N0M0. Results: 10 patients (16.7%) presented with SN+ (sentinel node positive). The majority (80%) only presented subcapsular affection, however one case also presented with extracapsular affection. Using the Kaplan-Meier curves, we determined that the average survival estimation for SN- patients was 74.0 months (CI95% 67.6-80.5) and it was 45.4 months (CI95% 10.9-24.0) for SN+ patients (p = 0.002). SN+ patients presented an OR = 11.000 (CI95% 2.393-50.589, p = 0.002) for cancer-related mortality. In terms of the diagnostic performance of the SN (sentinel node) test, a 55% sensitivity, a 100% specificity, 100% PPV and a 84% NPV were obtained. The analysis using ROC (receiver operating characteristic) curves revealed an AUC = 0.671 (CI95% 0.492-0.850, p = 0.046). Conclusions: SLNB seems to be an adequate technique for the detection of hidden metastases.

A new morphologic classification of the alveolar ridge after distraction osteogenesis in human patients. A 17 years retrospective case series study / Una nueva clasificación morfológica de la cresta alveolar después de la distracción osteogénesis en pacientes humanos. Un estudio de serie de casos retrospectivo de 17 años

Background: To perform a morphologic classification based on the results of bone augmentation after a distractionosteogenesis.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 dentalimplants. Ridge bone morphology was evaluated as the main ordinal variable. Chi-squared, Kruskal-Wallis andANOVA one-way test were used.Results: Category I (30.95%): consisted of wide alveolar rim and no bone defects Category II (28.57%): widealveolar rim, lateral bone surface concavity. Category III (23.81%): narrow alveolar rim, lateral bone surface con-cavity. Category IV (2.38 %): distraction transport segment forming a bridge, without bone formed beneath andrequiring guided bone regeneration. Category V (9.52%): return of the transport segment to its initial position dueto 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 Ito 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 heightachieved decreases as the category increases, due to the accompanying osteogenic limitations (p<0.001). The im-plants placed in category I were longer 11.5 ± 0.9 mm (CI95% 10.9-11.9 mm) compared to those placed in categoryIII 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 categorieswhich provide a useful basis for decision-making regarding implant placement.(AU)

Metabolic syndrome and masticatory hypofunction: a cross-sectional study.

The objective of this paper is to clarify the rate of abdominal obesity (AO), waist-to-height ratio (WHtR), metabolic syndrome (MetS) and determine the relationship with the masticatory capacity (MC) in terms of total functional tooth units (t-FTU) in a representative sample of older Spanish adults. This cross-sectional study included 544 adult subjects aged 50 or over, who were prospectively selected and who had participated in a survey conducted in a primary dental care service in a Public Oral Health Service in Spain. Anthropometric, clinical variables and t-FTUs were obtained through a calibrated and well-established protocol. Univariate and multivariate binary and multinomial logistic regression analyses were developed. With regards to the t-FTU or MC, it was poor in 60.3%, good in 17.6%, and complete in 22.1% of the sample. The univariate odss ratio (OR) for MetS and AO increased as the MC decreased and as the age group increased. With regards to gender, women presented with an OR of 5.56 (CI 95% 3.70-8.38). With regards to the WHtR-a3 (WHtR grouped into three categories), the univariate ORs were all significant for morbid obesity compared to the healthy group, with a risk of 6.86 (CI 95% 3.23-14.58) for patients with poor MC compared to those with complete MC. Masticatory hypofunctionality could be associated with the presence of MetS. Clinical relevance: The number of t-FTUs is directly related to AO.

Efficacy of different formulations of nystatin in an experimental model of oral candidiasis in sialoadenectomized rats.

BACKGROUND/PURPOSE: Oral candidiasis is the most common fungal infection of the oral cavity and has become a focus of attention in recent years because of its association with highly topical immunosuppressive conditions. The aims of this study were to determine the value of microbiological, clinical and histological parameters of Candida albicans colonisation of the dorsal tongue surface as indicators of disease severity, and to evaluate therapeutic response to different formulations of nystatin. MATERIALS AND METHODS: We used 84 males, 2-month-old Sprague-Dawley sialoadenectomized rats. Different formulations of nystatin were used to evaluate the therapeutic response. The animals were randomized to 2 groups with each of 42 animals and received the experimental treatments from day 17-22. RESULTS: 100% of the rats showed evidence of infection. At 5 and 10 days of starting treatment with nystatin + chitosan, and at 10 days of starting nystatin + orabase, the number of animals with positive dorsal tongue culture decreased significantly (p < 0.05), acting the Nystatin + chitosan more rapidly against Candida. In the control group, the percentage of normal papillae on day 22 and 27 was 83.33% (SD = 1.50) and 79.08% (SD = 2.30), respectively. Significant differences were observed in the mean O'Grady score at 5 and 10 days (p < 0.0001). CONCLUSION: The model has been shown to be effective in inducing infection, and that the combination of nystatin and chitosan yielded the best therapeutic outcomes at both 5 and 10 days after infection.

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.

Trypanosoma cruzi Induces B Cells That Regulate the CD4+ T Cell Response.

Trypanosoma cruzi infection induces a polyclonal B cell proliferative response characterized by maturation to plasma cells, excessive generation of germinal centers, and secretion of parasite-unrelated antibodies. Although traditionally reduced to the humoral response, several infectious and non-infectious models revealed that B lymphocytes could regulate and play crucial roles in cellular responses. Here, we analyze the trypomastigote-induced effect on B cells, their effects on CD4+ T cells, and their correlation with in vivo findings. The trypomastigotes were able to induce the proliferation and the production of IL-10 or IL-6 of naïve B cells in co-culture experiments. Also, we found that IL-10-producing B220lo cells were elicited in vivo. We also found up-regulated expression of FasL and PD-L1, proteins involved in apoptosis induction and inhibition of TCR signaling, and of BAFF and APRIL mRNAs, two B-cell growth factors. Interestingly, it was observed that IL-21, which plays a critical role in regulatory B cell differentiation, was significantly increased in B220+/IL-21+ in in vivo infections. This is striking since the secretion of IL-21 is associated with T helper follicular cells. Furthermore, trypomastigote-stimulated B-cell conditioned medium dramatically reduced the proliferation and increased the apoptotic rate on CD3/CD28 activated CD4+ T cells, suggesting the development of effective regulatory B cells. In this condition, CD4+ T cells showed a marked decrease in proliferation and viability with marginal IL-2 or IFNγ secretion, which is counterproductive with an efficient immune response against T. cruzi. Altogether, our results show that B lymphocytes stimulated with trypomastigotes adopt a particular phenotype that exerts a strong regulation of this T cell compartment by inducing apoptosis, arresting cell division, and affecting the developing of a proinflammatory response.

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.

Exosomes in head and neck cancer. Updating and revisiting.

Exosomes have gone from being considered simple containers of intracellular waste substances to be considered important carriers of cellular signals. Its broad capacity to promote tumour growth, both in situ and metastatic, has greatly intensified scientific research on them. In the same way and depending on its content, its tumour suppressive properties have opened a window of light and hope in the fight against cancer. In the present review we try to gather in a simple and understandable way the most relevant knowledge to date on the role of exosomes in oral squamous cell carcinoma, helping to understand their process of formation, release and activity on the tumour microenvironment.

Metabolic Labeling of Surface Neo-sialylglyconjugates Catalyzed by Trypanosoma cruzi trans-Sialidase.

Trypanosoma cruzi, the protozoan agent of Chagas disease, has evolved an innovative metabolic pathway by which protective sialic acid (SA) residues are scavenged from host sialylglycoconjugates and transferred onto parasite surface mucin-like molecules (or surface glycoconjugates from host target cells) by means of a unique trans-sialidase (TS) enzyme. TS-induced changes in the glycoprotein sialylation profile of both parasite and host cells are crucial for the establishment of a persistent T. cruzi infection and for the development of Chagas disease-associated pathogenesis. In this chapter, we describe a novel metabolic labeling method developed in our labs that enables straightforward identification and molecular characterization of SA acceptors of the TS-catalyzed reaction.