Oral Mucositis and Nutritional Status in Children Who Underwent Hematopoietic Cell Transplantation: A Comparison Between Nonmalignant and Malignant Primary Diseases.

BACKGROUND: There is a lack of studies analyzing the association between oral mucositis (OM) and nutritional imbalance in children during hematopoietic stem cell transplantation (HSCT). The aim of this study was to compare the risk factors for OM and nutritional imbalance during HSCT in pediatric patients with nonmalignant diseases (NMD) and malignant diseases (MD). METHODS: Data on age, sex, primary disease, transplantation type, conditioning regimen, GVHD prophylaxis, gastrointestinal toxicity, OM, percent body weight loss or gain, nutritional repositioning, and overall survival (OS) were retrospectively collected from the 132 medical records. The data were then compared between patients with NMD (n = 70) and MD (n = 62). RESULTS: OM had a similar severity between the groups. The primary risk factor for OM in the NMD group was the conditioning regimen with busulfan, while in the MD group it was GVHD prophylaxis with cyclosporin and methotrexate. OM did not have an impact on body weight loss or gain in any of the groups. In the NMD, body weight gain due to fluid overload was more pronounced and associated with a lower age range. OS was similar between the groups and was not affected by OM. CONCLUSIONS: OM pattern was similar in pediatric patients with or without MD, but the factors that determined these oral lesions were different. There were disparities in body weight changes between the two groups, and these changes were not associated to OM.

Photodynamic therapy in cancer stem cells - state of the art.

Despite significant efforts to control cancer progression and to improve oncology treatment outcomes, recurrence and tumor resistance are frequently observed in cancer patients. These problems are partly related to the presence of cancer stem cells (CSCs). Photodynamic therapy (PDT) has been developed as a therapeutic approach for solid tumors; however, it remains unclear how this therapy can affect CSCs. In this review, we focus on the effects of PDT on CSCs and the possible changes in the CSC population after PDT exposure. Tumor response to PDT varies according to the photosensitizer and light parameters employed, but most studies have reported the successful elimination of CSCs after PDT. However, some studies have reported that CSCs were more resistant to PDT than non-CSCs due to the increased efflux of photosensitizer molecules and the action of autophagy. Additionally, using different PDT approaches to target the CSCs resulted in increased sensitivity, reduction of sphere formation, invasiveness, stem cell phenotype, and improved response to chemotherapy. Lastly, although mainly limited to in vitro studies, PDT, combined with targeted therapies and/or chemotherapy, could successfully target CSCs in different solid tumors and promote the reduction of stemness, suggesting a promising therapeutic approach requiring evaluation in robust pre-clinical studies.

Prognostic factors for femoropopliteal vascular injuries: surgical decisions matter.

Background: Lower limbs are frequently involved in vascular trauma, but it is still not clear which factors lead to unfavorable clinical outcomes. Objectives: To determine the clinical profile of patients with femoropopliteal injuries, the trauma mechanisms, and treatment and identify which factors led to unfavorable outcomes. Methods: A retrospective study based on the medical records of patients treated from 2017 to 2021. The following data were assessed: sex, age, distance to reach the hospital, trauma mechanism, hypovolemic shock, additional injuries, treatment of vascular injuries, whether fasciotomy was needed, inappropriate intraoperative decisions, and injury severity score. Need for surgical reintervention, amputation, and death were defined as unfavorable outcomes. Univariate, bivariate, and logistic regression analyses were conducted. Results: The sample comprised 94 patients; 83% were men; mean age was 30.8 years; combined arterial and venous injuries prevailed (57.5%); and superficial femoral vessels were the most affected (61.7%). Penetrating mechanisms prevailed (80.9%). Arterial injuries were most frequently treated with venous graft (59.6%) and venous injuries underwent ligation (81.4%). In 15% of cases, inappropriate surgical decisions were detected; most often use of the ipsilateral great saphenous vein for arterial reconstruction. Unfavorable outcomes occurred in 44.7%: surgical reintervention was necessary in 21.3% and limb amputation in 25.5%, while 9.5% of the patients died. Conclusions: These injuries mainly involved young men, victims of gunshot wounds. Superficial femoral vessels were the most injured; concomitant non-vascular trauma was frequent, mainly fractures. Inappropriate surgical decisions increased the need for reinterventions by 34 times. Need for fasciotomy, presence of fracture/dislocation, blunt trauma mechanism, and popliteal artery injury increased the risk of amputation.

Effect of chronic ethanol ingestion on dendritic cell population during oral mucosal repair: An experimental study.

The aim of this study was to analyze the effect of chronic ethanol ingestion on dendritic cell repopulation during the repair process of rat oral mucosa and in the rat spleen by analyzing the immunohistochemical expression of dendritic cell markers. Wistar rats ingested 20% ethanol solution for 28 days; a surgical wound was performed on the rat tongue after this period. The repair process and the number of CD1a+, CD11c+, and CD207+ cells in the regions adjacent to the wound were determined at day 1, 3, and 7 following the wound as well as in the rat spleen. The wound-only group (no ethanol exposure) had complete reepithelization after 7 days, but this did not occur in the ethanol + wound group at this time point. The inflammatory infiltrate was significantly reduced in animals exposed to ethanol, which also showed significantly lower counts of CD1a+, CD11c+, and CD207+ cells than the wound-only group at all experimental time points. In addition, ethanol exposure also resulted in lower densities of CD11c+ and CD207+ cells in the rat spleen. In conclusion, chronic ethanol intake had a negative impact on dendritic cell numbers, a fact that may contribute to delay in oral mucosa repair.

Does Photobiomodulation Affects CK10 and CK14 in Oral Mucositis Radioinduced Repair?

The mechanisms of action of photobiomodulation (PBM) in oral mucositis (OM) are not completely elucidated. To enlighten the role of PBM in the evolution of epithelial maturity in OM ulcers, the present study evaluated the effect of PBM with red (λ) wavelength of 660 nanometers (nm) and infrared of 780 nm in radio-induced OM wounds on the tongue of rats, eight and twenty days after irradiation with single dose of 20 Gy. The percentage area corresponding to positive staining for cytokeratin 10 (CK10) and 14 (CK14) proteins was evaluated in the epithelial area of the lesions, using an immunohistochemical technique (IHC), 8 and 20 days after the induction of lesions, and compared with an untreated control group. CK10 was significantly more expressed in the group treated with 660 nm PBM. CK14 did not show quantitative differences between the groups evaluated. However, whereas in the groups treated with PBM, CK14 was already restricted to the basal layer of the epithelium, as expected in healthy epithelia, in control group it was also expressed in upper layers of the epithelium. In this work, PBM was able to improve epithelial maturity of the repaired OM wound, especially in the 660 nm group.

Salivary antioxidant enzymes associated with oral toxicity in haematopoietic cell transplantation: An observational study.

BACKGROUND: In haematopoietic cell transplantation (HCT), oral mucositis and xerostomia are related to conditioning-related oxidative stress. The role of salivary antioxidant enzymes in oral toxicity is poorly described. The aim of this study was to verify the association between salivary antioxidant enzymes and oral mucositis and xerostomia in HCT. DESIGN: Saliva from autologous and allogeneic HCT patients (n = 77) was selected before conditioning (T0), during the neutropenia period (T1) and after marrow engraftment (T2). Salivary flow, total salivary proteins, and superoxide dismutase, catalase and glutathione reductase activities were measured. RESULTS: There were no significant differences in salivary flow, total salivary proteins and catalase at the three HCT time points. Glutathione reductase levels were reduced at T1 compared to T0 (P = .013) and T2 (P = .001). Superoxide dismutase levels were increased from T0 to T2 (P = .013). Neither of these enzymes was associated with oral mucositis. Increased superoxide dismutase levels were associated with xerostomia frequency. Levels of this enzyme also showed significant correlation with days of xerostomia in T2 (ρ = .40, P = .002). CONCLUSIONS: Salivary antioxidant enzymes changed before and during early periods after HCT. The increase in salivary superoxide dismutase suggested partial activation of the salivary antioxidant system and was associated with xerostomia.

Long-term safety of photobiomodulation therapy for oral mucositis in hematopoietic cell transplantation patients: a 15-year retrospective study.

Photobiomodulation therapy (PBMT) has demonstrated efficacy in the prevention and treatment of oral mucositis (OM) in hematopoietic cell transplantation (HCT). However, based on the cell stimulation properties, its long-term safety has been questioned, mainly in relation to risk for secondary malignancies in the oral cavity. The aim of this study was to investigate if different PBMT protocols for OM control have association with immediate and late adverse effects in HCT patients. Data on autologous and allogeneic transplantation, conditioning regimen, PBMT protocols, and OM severity were retrospectively collected from medical and dental records. Presence of secondary malignancies in the oral cavity was surveyed during a 15-year follow-up. Impact of OM on overall survival was also analyzed. Different PBMT protocols for prevention and treatment of OM were recorded over the years. Severe OM (grades 3 and 4) was infrequently observed. When present, we observed a significant decrease of the overall survival. No immediate adverse effect and secondary malignancy was associated to PBMT. In conclusion, the PBMT protocols used in the study were considered safe. The low frequency of severe OM observed encourages the implementation of this technique, with a special emphasis on the dosimetry adjustments focused on the HCT context.

Is Salivary Busulfan the Cause of Oral Mucositis and the Changes in Salivary Antioxidant Enzymes After Hematopoietic Cell Transplantation?

BACKGROUND: To determine whether the busulfan (Bu) present in saliva during hematopoietic cell transplantation (HCT) conditioning correlates with oral mucositis and the changes in salivary antioxidant enzymes. METHODS: Bu levels in the plasma and saliva of 19 patients who received HCTs were quantified. Salivary flow and salivary superoxide dismutase and catalase activities were measured during HCT. For the toxicity analysis of salivary Bu, an in vitro assay was conducted by exposing human keratinocytes to artificial saliva containing Bu. RESULTS: Plasma and salivary Bu concentrations were very similar (rho = 0.92, P < 0.001). Salivary Bu concentration correlated with the degree of oral mucositis severity (rho = 0.391, P = 0.029) and was inversely proportional to salivary superoxide dismutase and catalase activities (rho = -0.458, P = 0.036; rho = -0.424, P = 0.043, respectively). Cells exposed to Bu-containing saliva had fewer viable cells (P < 0.01) and more apoptotic cells (P = 0.001) than those exposed to non-Bu-containing saliva. CONCLUSIONS: Bu found in saliva during HCT conditioning was correlated with severe oral mucositis and the reduction in salivary antioxidative activity. Furthermore, Bu can be toxic to keratinocytes.

Association of oral toxicity and taste changes during hematopoietic stem cell transplantation: a preliminary study.

PURPOSE: The aim of this study was to characterize the taste changes and taste bud atrophy observed in the period of neutropenia of HCT and to determine the influence of transplantation toxicity on these changes. METHODS: Autologous and allogeneic HCT patients (n = 51) were selected to perform taste acuity tests prior to conditioning (T0) and during neutropenia (T1). The frequency and time duration of oral mucositis, presence of tongue depapillation, and salivary flow rate were also evaluated. Quality of life was assessed using specific questionnaires. RESULTS: We observed a significant increase in hypogeusia (66.6%, p = 0.001) and dysgeusia (21.4%, p = 0.013) at T1, compared with T0. Bitter taste was the most altered, mainly when the patient underwent conditioning with melphalan (OR = 4.47, p = 0.049). Prolonged oral mucositis (≥ 8 days) (OR = 5.62, p = 0.039) and autologous transplantation (OR = 4.08, p = 0.033) were predictive factors for tongue depapillation. Changes in sour taste (OR = 10.70, p = 0.045) and reduced salivary flow (OR = 21.00, p = 0.013) were associated to body weight loss at T1. Taste changes significantly reduced the quality of life at T1, compared with T0. CONCLUSIONS: Frequency of hypogeusia was high in the neutropenia period of the HCT. None of the taste changes was determined by oral mucositis, tongue depapillation, or reduced salivary flow, but melphalan conditioning reduced the bitter taste sensation. Loss of body weight and poor quality of life were associated with taste changes and reduced salivary flow. Further studies are necessary to elucidate this association and the risk factors for taste changes in HCT.

The effect of a single irradiation of low-level laser on nipple pain in breastfeeding women: a randomized controlled trial.

Photobiomodulation with low-level laser therapy (PBM-LLLT) has been introduced as a new tool to relieve nipple pain and repair nipple damage in breastfeeding women; however, evidence is needed to assess its effectiveness. The aim was to evaluate the effect of a single application of PBM-LLLT for breastfeeding women with nipple pain and damage; side effects were also collected. We conducted a randomized double-blinded controlled trial with women with nipple damage who were exclusively breastfeeding and rooming-in at Amparo Maternal maternity service, São Paulo, Brazil (May 2016 to May 2017). Women were randomly assigned into laser (n = 40) or control group (n = 40). Intervention was a single irradiation (660 nm, 100 mW, 2 J, 66.66 J/cm2, 3.3 W/cm2, 20 s of irradiation, punctual, and continuous mode) applied directly. Women reported pain levels at recruitment (before and immediately after irradiation), 6 and 24 h after the treatment. Pain level during a breastfeed was assessed using the Visual Analogue Scale (0 to 10). The primary outcome was the level of nipple pain immediately after the laser irradiation. Data were analyzed using hierarchical model and Wald test. At baseline, pain levels were similar (mean of 7.4 in laser group and 7.1 in control group). Women's perception of pain reduced approximately one point in both groups. Thirty-one percent of participants in the laser group (11/36) reported secondary effects, such as tingling (10/36) and pricking (2/36). The laser protocol of a single application was not effective in reducing pain in women with damaged nipples. Tingling sensation may be experienced by women receiving laser treatment for nipple damage.

Photobiomodulation as an adjunctive therapy for alveolar socket preservation: a preliminary study in humans.

Bone remodeling results in loss of alveolar bone height and thickness. Photobiomodulation (PBM) based on photochemical stimulation by low-intensity lasers emerges as an adjunctive therapy for alveolar socket preservation. Our study aimed to evaluate the effects of PBM therapy on alveolar bone repair. Twenty healthy patients in need of bilateral extraction of lower molars were enrolled in this split-mouth randomized and blind clinical trial. The extraction sites were randomly selected to receive either the PBM therapy with a CW GaAIAs diode laser (808 nm; 0.028 mm2; 0.1 W; 3.6 W/cm2; 89 J/cm2; 2.5 J/point) or no treatment (Control). Bone biopsies were harvested 45 days after the dental extraction and evaluated using micro-computerized tomography (µCT), morphometric, and histological analysis. Data were compared using the paired t test, and the level of significance was set at 5%. Bone surface (p = 0.029), bone surface/total volume (p = 0.028), trabecular number (p = 0.025), and connectivity density (p = 0.029) were higher at the PBM group compared with Control. The histological observations confirmed the µCT findings. PBM samples exhibited higher number of organized and connected bone trabeculae along with higher density of blood vessels than Control. Control samples displayed a dense and highly cellular connective tissue at the central area accompanied by the presence of immature bone trabeculae at the periphery. Our results indicated that the PBM therapy improved the newly bone trabeculae formation and their connectivity which increased bone surface, indicating the positive effect of the laser on alveolar human socket repair.

Retrospective study of the digestive tract mucositis derived from myeloablative and non-myeloablative/reduced-intensity conditionings with busulfan in hematopoietic cell transplantation patient.

Busulfan is a major component of chemotherapy conditioning in hematopoietic cell transplantation (HCT). This alkylating agent is highly toxic at myeloablative doses, exposing HCT patients to risks of mortality. Non-myeloablative (NMA) and reduced-intensity conditioning (RIC) using busulfan have shown impaired toxicity. However, the toxicity of NMA/RIC in the digestive tract is poorly described. This study aimed to characterize the mucositis in the oral cavity (OM), oropharynx/esophagus, and gastrointestinal tract derived from conditionings with myeloablative and non-myeloablative doses of busulfan. We retrospectively retrieved clinical data of HCT patients (n = 100) who underwent myeloablative conditioning (MAC) or NMA/RIC with busulfan. Frequency and time duration of mucositis in the oral cavity and oropharynx/esophagus, diarrhea, and prescription of total parenteral nutrition (TPN) and opioids were also collected. OM severity (p = 0.009) and time duration of mucositis in oropharynx/esophagus (p = 0.022) were frequently higher in MAC than NMA/RIC. A myeloablative dose of busulfan was a risk factor for OM grade ≥ 2 (OR = 4.8, p = 0.002) and for mucositis in oropharynx/esophagus ≥ 5 days (OR = 2.64, p = 0.035). A longer duration of mucositis in the oropharynx/esophagus was also associated with an increase in the prescription of opioids (OR = 7.10, p < 0.001).Overall survival (OS) in MAC was significantly higher than that in NMA/RIC (p = 0.017). No variables related to mucositis interfere significantly in OS. In conclusion, myelosuppression in busulfan-based regimens are predisposed to a high risk for severe OM and to prolonged mucositis in the oropharynx/esophagus.

Immunohistochemical analysis of BRAF V600E mutation in ameloblastomas.

OBJECTIVE: This study aimed to investigate the presence of BRAF V600E mutation in mandible ameloblastomas by correlating clinical and imaging data on the cases studied. METHODS: Eighty-four cases diagnosed as mandibular ameloblastoma were selected for analysis. The specimens were submitted to immunohistochemistry for detection of BRAF V600E mutated protein. Clinical-pathological data such as age, gender, tumour size, mandibular location, radiographic aspects, histological type and sub-type, and tumour status were collected. The clinical-pathological parameters were categorised and analysed according to BRAF V600E detection. RESULTS: Of the 84 patients, 78.6% (66 cases) demonstrated positivity for anti-BRAF V600E antibody, whereas 18 were negative (21.4%). The correlation between BRAF expression and variables showed statistical significances for mandibular location (P = 0.0353) and tumour size (P = 0.008), whereas no statistical significance was observed for gender, age, radiographic aspect, histological pattern, histological sub-type and tumour status. Multivariate logistic regression revealed a significant risk for BRAF positivity in tumours with posterior mandibular location (OR = 7.23, P = 0.0451) and size > 4 cm (OR = 7.29, P = 0.0150). CONCLUSION: BRAF V600E mutation is common in mandibular ameloblastomas, especially in cases of tumours larger than 4 cm and in the posterior region of the mandible. In addition, this mutation can occur regardless of histological type of the tumour, age, gender, radiographic aspect and tumour status. CLINICAL SIGNIFICANCE: The association between clinical-pathologic features and BRAF V600E mutation in ameloblastomas may provide directions for the treatment of this neoplasia. The use of BRAF inhibitors for targeted therapy could lead to an establishment of an alternative compared to the resective surgery.

Resistance of oral cancer cells to 5-ALA-mediated photodynamic therapy.

Photodynamic therapy (PDT) has been indicated for oral squamous cell carcinoma (OSCC) at early stages. Chemo and radio-resistance are frequently observed in OSCC, but it is unknown whether this tumor can develop resistance to PDT. It was investigated the process of acquiring resistance to multiple cycles of PDT by using OSCC cells. We also analyzed the expression of anti-apoptotic proteins and those related to Akt/mTOR pathway. Sub-lethal doses of PDT were applied, consisting of a constant concentration of 5-aminolevulinic acid (5-ALA) (1 mM, 4-h incubation) and increasing irradiation dose with LED (from 5.86 to 10.54 J/cm2 ). Cell viability, migration capacity, intracellular expression of protoporphyrin IX (PpIX), mitochondrial density, and pro-survival proteins were investigated in PDT-resistant cells. Six OSCC cell generations resistant to PDT were isolated. The resistant cells exhibited a survival phenotype characterized by a reduction in the expression of endogenous PpIX, increase in mitochondrial density, increase in migration capacity, and up-regulation of p-NFκB, p-survivin, iNOS, p-Akt Ser473 , cyclin D1, p-mTOR Ser2481 , and p-mTOR Ser2448 . OSCC cells are able to survive doses of 5-ALA-PDT by reducing PpIX synthesis and activating signaling pathways related to the inhibition of apoptosis and improvement of cell proliferation. Further studies are necessary to confirm whether this PDT-resistance phenotype can be clinically present, mainly in OSCC showing clinical recurrences after exposure to different PDT protocols.

Impact of Oral and Gastrointestinal Mucositis on Body Weight Alterations during Hematopoietic Stem Cell Transplantation.

The aim of this study was to evaluate whether digestive tract mucositis is a predictive factor for body weight (BW) alterations during hematopoietic stem cell transplantation (HSCT). Data about characteristics of transplantation, initial nutritional conditions and gastrointestinal mucositis were collected from adult patients (n = 105) who underwent autologous and allogeneic HSCT. Oral mucositis (OM) was not a predictive factor for BW loss, but it was an independent factor for BW gain in autologous HSCT (ß = 0.329, P = 0.021). Busulfan-fludarabine conditioning regimen (ß = 1.531, P = 0.011) and gender (ß = 1.109, P = 0.038) were significant independent risk factors for BW loss in allogeneic HSCT. Overall survival (OS) was significantly affected by the duration of OM in autologous HSCT (HR = 1.243, P = 0.008). In allogeneic HSCT, BW loss (HR = 1.308, P = 0.049) and diarrhea (HR = 1.139, P = 0.012) interfered significantly with OS. In conclusion, OM was not a risk factor for BW loss, but it influenced BW gain and had a negative impact on OS in autologous HSCT patients. Intestinal mucositis explained partially the BW loss and had a negative impact on OS in allogeneic HSCT.

Comparison of Pixel Values of Maxillary Sinus Grafts and Adjacent Native Bone With Cone-Beam Computed Tomography.

PURPOSE: Pixel values from cone-beam computed tomography (CBCT) are proportional to bone density. This study aimed to correlate and compare pixel values of healed maxillary sinus grafts and adjacent native bone (NB). MATERIAL AND METHODS: This study was conducted on CBCT scan patients referred for maxillary sinus floor augmentation with biphasic calcium phosphate (n = 31). Graft height and width measurements were performed. In addition, mean pixel values were calculated in 3 different regions: NB, sinus graft close to NB (CNB), and sinus graft far from NB (FNB). Micro-CT and histological analyses of bone specimens of a representative case were also performed. RESULTS: Significant correlations were found between CNB and graft height (r = 0.41; P < 0.021); and FNB and graft width (r = 0.519, P < 0.003). In addition, pixel values from both graft groups (CNB and FNB) differed significantly (P < 0.001). Finally, histological sections revealed smaller areas with newly formed bone in the FNB area. CONCLUSIONS: Within the limitations of this study, the present findings suggest that pixel values of sinus grafted areas are directly correlated with the extension of the grafted area.

Minor salivary gland biopsy for the diagnosis of familial amyloid polyneuropathy.

The diagnosis of Val30Met familial amyloidotic polyneuropathy (FAP) is based on genetic tests, clinical manifestations, familial history and biopsy of peripheral tissues (e.g. rectum, abdominal fat pad, sural nerve, and minor salivary gland) to confirm the presence of amyloid deposits. The aim of this study was to determine the frequency of amyloid deposits in minor salivary glands biopsied from FAP patients and to investigate whether an association exists between the presence of these deposits and clinical features. Seventeen patients with FAP were submitted to minor salivary gland biopsy to confirm the presence of amyloid deposits. The histopathology of the salivary glands confirmed glandular amyloid deposits in nine symptomatic patients (sensitivity of 75.0%). In general, FAP patients who tested positive for glandular amyloid deposits exhibited significantly higher frequencies of sensorimotor and dysautonomic dysfunctions (p = 0.001) compared with those who tested negative. None of the patients reported xerostomia. Minor salivary gland biopsy may help confirm the diagnosis of FAP in symptomatic cases, as it is noninvasive, easy to execute, and causes minimal discomfort to patients.

Vascular alterations after photodynamic therapy mediated by 5-aminolevulinic acid in oral leukoplakia.

Impairment of vascular functions after photodynamic therapy (PDT) is frequently associated with tumor remission and is considered one of the main antineoplastic PDT effects. Vascular alterations in oral leukoplakia (OL) treated with PDT have not yet been described. The aim of this study was to evaluate the effect of topical 5-ALA-mediated PDT on the vascular network of 4NQO-induced OL in rats. After applying 4NQO topically on the tongue during 16 weeks, there was induction of dysplastic lesions, which were treated with two PDT sessions (with an interval of 72 h between them), using topical application of 5-ALA and posterior irradiation with a laser (90 J/cm2 fluency). Histological sections of the tongues were obtained and analyzed concerning plasmatic exudation and microvessel density after immunolabeling with CD31 and CD34 vessel markers. There was intense plasmatic exudation after 6 h of the first PDT session; at 6 h of the second PDT session, there was a significant reduction in the density of CD31- and CD34-positive microvessels in comparison to controls (p < 0.05). In the PDT intervals, there was an increase in the density of CD31 and CD34 microvessels, suggesting angiogenesis. Topical application of 5-ALA-mediated PDT caused an immediate deleterious effect on the vascular network, increasing vessel permeability and reducing vessel density, mainly after two sessions of the treatment. However, secondary angiogenesis emerged in these lesions during intervals of the PDT session. This fact may be considered during the adoption of a PDT protocol, to avoid OL resistance and recurrence after the treatment.

Oral shedding of human herpesviruses in patients undergoing radiotherapy/chemotherapy treatment for head and neck squamous cell carcinoma.

OBJECTIVE: Opportunistic infections may affect the oral mucosa of patients undergoing radio/chemotherapy through exacerbation of oral mucositis. The aim of this study is to evaluate the oral shedding of all eight human herpesviruses and its possible association with oral mucositis. MATERIALS AND METHODS: In this prospective cohort study, we analyzed oral rinse samples, collected weekly, from 20 patients during radiotherapy treatment. Serologic status to HSV1 and HSV2, EBV, CMV, and VZV in three different periods was performed by ELISA assay. PCR and enzymatic digestion was performed to detect HSV1, HSV2, EBV, CMV, VZV, HHV6, HHV7, and HHV8. Oral mucositis was evaluated according to the WHO criteria. RESULTS: Oral shedding of EBV, HHV6, and HHV7 was observed in all weeks of radiotherapy. Considering the episodes of shedding, the highest frequency was found in patients with EBV excretion (55.0%). No virus reactivation was observed by serological analysis. EBV oral shedding frequency was significantly higher than that of other viruses and showing a positive correlation with oral mucositis grade ≥2. CONCLUSIONS: There was a positive correlation between EBV oral shedding and oral mucositis grade ≥2, particularly after 3 weeks of radiotherapy, a period in which the severity of mucositis was statistically higher. These findings allow us to infer that the local inflammatory environment in mucositis grade ≥2 is more favorable for EBV replication. CLINICAL RELEVANCE: Mucositis is a frequent and important side effect of radio/chemotherapy treatment. Understanding the possible participation of viruses in the mechanism of this condition is important to develop strategies for treatment and prevention.

Using Fourier transform infrared spectroscopy to evaluate biological effects induced by photodynamic therapy.

BACKGROUND AND OBJECTIVE: Vibrational spectroscopic methods associated with multivariate statistical techniques have been succeeded in discriminating skin lesions from normal tissues. However, there is no study exploring the potential of these techniques to assess the alterations promoted by photodynamic effect in tissue. The present study aims to demonstrate the ability of Fourier Transform Infrared (FTIR) spectroscopy on Attenuated total reflection (ATR) sampling mode associated with principal component-linear discriminant analysis (PC-LDA) to evaluate the biochemical changes caused by photodynamic therapy (PDT) in skin neoplastic tissue. MATERIALS AND METHODS: Cutaneous neoplastic lesions, precursors of squamous cell carcinoma (SCC), were chemically induced in Swiss mice and submitted to a single session of 5-aminolevulinic acid (ALA)-mediated PDT. Tissue sections with 5 µm thickness were obtained from formalin-fixed paraffin-embedded (FFPE) and processed prior to the histopathological analysis and spectroscopic measurements. Spectra were collected in mid-infrared region using a FTIR spectrometer on ATR sampling mode. Principal Component-Linear Discriminant Analysis (PC-LDA) was applied on preprocessed second derivatives spectra. Biochemical changes were assessed using PCA-loadings and accuracy of classification was obtained from PC-LDA . RESULTS: Sub-bands of Amide I (1,624 and 1,650 cm(-1) ) and Amide II (1,517 cm(-1) ) indicated a protein overexpression in non-treated and post-PDT neoplastic tissue compared with healthy skin, as well as a decrease in collagen fibers (1,204, 1,236, 1,282, and 1,338 cm(-1) ) and glycogen (1,028, 1,082, and 1,151 cm(-1) ) content. Photosensitized neoplastic tissue revealed shifted peak position and decreased ß-sheet secondary structure of proteins (1,624 cm(-1) ) amount in comparison to non-treated neoplastic lesions. PC-LDA score plots discriminated non-treated neoplastic skin spectra from post-PDT cutaneous lesions with accuracy of 92.8%, whereas non-treated neoplastic skin was discriminated from healthy tissue with 93.5% accuracy and post-PDT cutaneous lesions was discriminated from healthy tissue with 89.7% accuracy. CONCLUSION: PC-LDA was able to discriminate ATR-FTIR spectra of non-treated and post-PDT neoplastic lesions, as well as from healthy skin. Thus, the method can be used for early diagnosis of premalignant skin lesions, as well as to evaluate the response to photodynamic treatment. Lasers Surg. Med. 48:538-545, 2016. © 2016 Wiley Periodicals, Inc.