Symptomatic subgemmal neurogenous plaque in patients with COVID-19: Is there an association?

BACKGROUND: Subgemmal neurogenous plaques (SNP) are composed of neural structures found in the posterolateral portion of the tongue, rarely biopsied as most of them are asymptomatic or eventually only clinically managed. We aimed to investigate a case series of possible correlation of symptomatic subgemmal neurogenous plaque (SNP) with coronavirus disease 2019 (COVID-19). METHODS: Eleven formalin-fixed paraffin-embedded cases from patients with previous confirmed COVID-19 (by RT-PCR) were retrieved from two pathology files. Histological sections were morphologically studied, and then submitted to immunohistochemical reactions against S-100 and neurofilament proteins, neuron-specific enolase, Glial fibrillary acidic protein (GFAP), synaptophysin, CD56, Ki67, cytokeratins (7, 8-18, 19, 20), nucleocapsid and spike proteins (SARS-CoV-1; and -2) and epithelial membrane antigen (EMA) antibodies. Clinical data were retrieved from the patients' medical files, including the symptoms and the complete history of the progression of the disease. RESULTS: The patients who had COVID-19 included in this study experienced painful lesions in the tongue that corresponded to prominent or altered SNP. Microscopically, neural structures were positive for S-100, GFAP and neurofilament protein. And the cellular proliferative index (by Ki-67) was very low. CONCLUSION: Thus, based on the current results, we hypothesize that symptomatic SNP may be a late manifestation of COVID-19 infection.

Effects at cellular level of epilation with various laser wavelengths applied simultaneously on different skins: two case reports.

This study evaluated the effects of laser application of diverse wavelengths applied simultaneously and on different skins. The sample included two participants, a woman with light skin with abdominal hair and a woman with dark skin and hair on the inner part of the lower limbs, who received a laser therapy session. After 45 days from laser application, abdominoplasty and thigh dermolipectomy surgery were performed. In the control sample, the hair follicles were in the anagen phase, showing the presence of Bcl-2 expression. In the treated areas, follicles were observed in an advanced phase (telogen), with the presence of CK-18 and negativity of Bcl-2, highlighting the phase of hair loss at that moment and the complete apoptosis of the investigated follicle. Significant difference was observed in the comparison of the anagen phase (p = .00) and it similarly occurred in the comparison of the telogen phase (p = .00). The presence of a greater amount of follicles in the anagen phase in the control area and follicles in the telogen phase in the treated area demonstrates the efficiency of the laser at different wavelengths when reaching different skin phototypes and hair thickness, being reinforced by apoptosis and cell proliferation markers. Therefore, the hair-removal process has been optimized with various laser wavelengths.

Expression of mitochondrial dynamic markers in adenoid cystic carcinoma.

BACKGROUND: Mitochondrial fission and fusion processes are known as mitochondrial dynamics and the occurrence of imbalances in the mitochondrial activity is related to the pathogenesis of many human cancers. However, the importance of mitochondrial dynamics in malignant salivary gland tumours remains unknown. Therefore, we aimed to investigate its prognostic significance in adenoid cystic carcinoma. METHODS: Fifty-seven formalin-fixed paraffin-embedded cases were retrieved and disposed in tissue microarray. Histological sections were submitted to immunohistochemical reactions against AMT, DRP1, FIS1, MFN1, MFN2 and OPA1 proteins. Clinical data were retrieved from the patients' medical files, including specific and disease-free survival data. RESULTS: It was observed that 50.9% of the cases were strongly positive for AMT and DRP1, and 49.1%, 21.1%, 22.8% and 24.6% strongly positive for FIS1, MFN1, MFN2 and OPA1, respectively. Reactions were observed in both epithelial and myoepithelial components of the tumour. The higher expression of MFN2 was associated with solid microscopic pattern (p = 0.016). DRP1 overexpression showed a trend towards a shorter overall survival (p = 0.054), while negative/weak OPA1 showed a trend towards a lower disease-free survival (p = 0.051) in the univariate analysis, but no mitochondrial marker represented an independent prognostic determinant under multivariate analysis. CONCLUSION: In conclusion, mitochondrial dynamics markers do not seem to carry a prognostic significance for adenoid cystic carcinoma patients, but these proteins may play an important role in its pathogenesis.

Oral and maxillofacial manifestations of IgG4-related disease: A clinicopathological study.

BACKGROUND: IgG4-related disease is a fibroinflammatory and immune-mediated condition, which has extremely variable clinical manifestations. In this study, we aim to investigate the clinicopathological features of IgG4-related disease involving the oral and maxillofacial region. METHODS: Cases of IgG4-related disease manifesting in the oral and maxillofacial region were retrieved from three Brazilian institutions. Clinical and serological data were obtained from the patients' medical charts, while microscopic and immunohistochemical findings were revised by oral pathologists. Diagnosis followed the American College of Rheumatology/European League against Rheumatism criteria. RESULTS: Seven patients diagnosed with IgG4-related disease were included in this study. Women were affected in all analysed cases, with a mean age of 55.4 years. Two patients presented with the clinical involvement of more than one oral and maxillofacial anatomic site. Therefore, our sample comprised nine oral and maxillofacial anatomic sites affected by IgG4-related disease. The submandibular gland was affected in four cases, the tongue and the parotid gland in two cases each, and the palate in one case. In a few cases, exploratory lower lip biopsy was used as a diagnostic approach. A moderate-to-severe lymphoid infiltrate containing plasma cells and lymphocytes, with an increased IgG4/IgG ratio, was common. Treatment varied and steroids were the most frequently used (57.4%). Six patients remained alive, while one died from unknown causes. CONCLUSION: Although major salivary glands are commonly affected by IgG4-related disease, the oral cavity can also be involved, and lower lip biopsy may be an auxiliary diagnostic tool.

Effects of LED photobiomodulation therapy on the subcutaneous fatty tissue of obese individuals - histological and immunohistochemical analysis.

Photobiomodulation therapy (PBMT) has become an adjuvant therapeutic possibility in body remodeling procedures. Given this scenario, this study was proposed with the aim of evaluating the effects of PBMT to Light Emitting Diode (LED) associating the red (630 nm) and infrared (850 nm) wavelengths in the subcutaneous fatty tissue. This controlled study of comparative intervention that evaluated a sample of subcutaneous fatty tissue from women with grade II obesity. The participants received the LED PBMT treatment with associated red and infrared wavelengths sequentially on the left side of the abdomen and the right side was considered as control, with the collection of biological material performed at the time of bariatric surgery. For histological and immunohistochemical evaluation, Caspase 3, Cleaved Caspase 3, CD68+, HSL and adipophilin markers were used. The participants showed positivity in the expression of Caspase 3 and Cleaved Caspase (p < .0001), CD68+ macrophages (p < .0001), HSL (p < .0001) and adipophilin (p < .0013) in the intervention sample when compared to the control. PBMT and LED associating red and infrared wavelengths were able to promote autophagic lipolysis induced by adipocyte cell apoptosis in the subcutaneous tissue of obese individuals.

Effect of extracorporeal shock waves on inflammation and angiogenesis of integumentary tissue in obese individuals: stimulating repair and regeneration.

The technology of extracorporeal shock wave therapy (ESWT) has been studied around the world for its possible benefits in the treatment and rehabilitation of aesthetic disorders. To better elucidate its real physiological effect on the integumentary tissue, this study was proposed aimed at evaluating whether ESWT can act to stimulate the inflammatory process and angiogenesis in the dermis and epidermis of obese individuals. This is an immunohistological study that evaluated a set of samples of the integumentary tissue of women with grade II obesity with weight loss of 10% of the initial weight undergoing ESWT treatment; the collection of biological material was performed at the time of surgery of bariatric surgery. For immunohistochemical evaluation, the markers to assess the presence and distribution of inflammatory cells, anti-COX-2, CD3, CD20, CD163, and NK were used. For physiological stimulus pathways for blood vessel angiogenesis, markers CD 34, CD 105 and VEGF were used. Fourteen obese women were included in the study. Positivity was evidenced in the epidermal expression of markers of the inflammatory process COX-2, CD3, CD20, NK cells, CD68, and CD163 (p < 0.0001) in the intervention sample when compared to controls. There was a positive expression for the angiogenesis markers CD105 and VEGF (p < 0.0001) when comparing the intervention group with the control group. It was concluded that ESWT can stimulate a local inflammatory process, mediating and modulating important growth factors to act in the repair process and skin tissue regeneration, being considered a promising treatment for skin diseases related to weight gain or loss.

Oral manifestations of Hydroa vacciniforme-like lymphoproliferative disorder: a clinicopathological study of a Peruvian population.

BACKGROUND: Hydroa vacciniforme-like lymphoproliferative disorder (HVLPD) is a chronic Epstein-Barr virus (EBV)-positive lymphoproliferative disease which may either present as an indolent condition or progress to a systemic T-cell lymphoma. METHODS: All HVLPD diagnosed over a 10-year period were retrieved, and clinical data regarding sex, age, oral and systemic manifestations, and clinical follow-up were obtained. Immunohistochemistry was done in order to characterize the lymphoid cells, and in situ hybridization was used to demonstrate the presence of EBV. RESULTS: Eleven cases were included, with a male predominance and a mean age of 25.1 years. Buccal mucosa and the lips were the most affected oral sites, appearing as painful ulcers. All patients exhibited facial oedema, usually affecting the lips, nose and periorbital region. The clinical course was gradual but progressive, with four patients having fever and 3 showing lymphadenopathies. All cases showed a moderate to severe lymphocytic infiltrate with angiotropism, angiocentricity and epidermotropism. Two cases affecting the lip skin exhibited a periappendageal lymphocytic infiltrate. Few large pleomorphic cells were found, surrounded by smaller and medium-sized lymphoid cells, as well as reactive plasma cells, macrophages, neutrophils and eosinophils. All lesions exhibited a cytotoxic T-cell (CD8+) phenotype with a variable proliferative index. All cases were associated with EBV, and all patients died due to complications of the disease. CONCLUSIONS: HVLPD is a rare disease that may show oral involvement with a cytotoxic T-cell phenotype, and is strongly associated with EBV. As shown in this series, HVLPD may show aggressive clinical behaviour.

Sialolipomas of minor salivary glands: A multi-institutional study and literature review.

BACKGROUND: Sialolipoma is a rare histological variant of lipoma commonly misdiagnosed and composed of a proliferation of mature adipocytes with secondary entrapment of normal salivary gland tissue. The purpose of the present study is to report the clinicopathologic and immunohistochemical features of 10 new cases of sialolipomas in conjunction with a review of the literature. METHODS: A retrospective descriptive cross-sectional study was performed. A total of 54,190 biopsy records of oral and maxillofacial lesions from four oral and maxillofacial pathology services in Brazil were analysed. All cases of lipomas were reviewed, and clinical, demographic and histopathological data were collected of all cases compatible with sialolipomas. In addition, immunohistochemistry stains (AE1/AE3, CK7, 34ßE12, S-100, HHF35, α-SMA and Ki-67) and a literature review based on a search of three electronic databases (PubMed, Web of Science and Scopus) were performed. RESULTS: Among all lipomas reviewed, there were 10 cases of sialolipomas. The series comprised of 7 females (70.0%) and 3 males (30.0%), with a mean age of 46.1 ± 21.5 years (range: 11-71 years) and a 2.3:1 female-to-male ratio. The lower lip (n = 3, 30.0%) and tongue (n = 2, 20.0%) were the most common locations, presenting clinically as a nodule of slow growth and normal colour. Conservative surgical excision was the treatment in all cases. No recurrence was observed. CONCLUSION: Sialolipomas are a rare histological variant of lipoma, affecting the salivary glands, mainly in the parotid gland and palate of female adults. Pathologists must recognise sialolipomas to avoid misdiagnoses with other lipomatous tumours that can affect salivary glands.

Oral and oropharyngeal lymphomas: A multi-institutional collaborative study.

BACKGROUND: Lymphomas in the oral and oropharyngeal regions are relatively uncommon, and their diagnosis is challenging and complex due to the myriad histopathological subtypes. Herein, we report a large series of oral and oropharyngeal lymphomas and compare our data with the currently available literature. METHODS: All cases diagnosed as lymphomas affecting the oral and oropharyngeal regions were retrospectively retrieved from seven Brazilian institutions. Clinicodemographic data and histopathological features were evaluated and described, while a comprehensive literature review was undertaken in order to compare our findings. RESULTS: A total of 304 cases of oral and oropharyngeal lymphomas were obtained, mostly affecting individuals aged 60-69 years (n = 68) with a mean age at diagnosis of 54.2 ± 20.1 years. Males and females were equally affected. Mature B-cell neoplasms (87.2%) were the most common group, followed by mature T- and NK-cell neoplasms (11.2%) and precursor lymphoid neoplasms (1.6%). The most frequent subtypes in each group were diffuse large B-cell lymphomas, not otherwise specified (n = 99), extranodal NK/T-cell lymphomas, nasal type (n = 12), and B-lymphoblastic leukaemia/lymphomas, not otherwise specified (n = 4). The most commonly involved sites were the palate (26.3%), mandible (13%), and maxilla (10.5%). CONCLUSION: Diffuse large B-cell lymphoma, not otherwise specified, remains the most common subtype of lymphomas in the oral and oropharyngeal region. Older patients are the most affected, with no gender predilection and the palate and jaw are usually affected.

Plasmacytoma and plasma cell myeloma affecting the jaws: A multi-institutional collaborative study.

BACKGROUND: Plasma cell neoplasms are characterized by the proliferation of a single clone of plasma cells with production of a monoclonal immunoglobulin. They can manifest as a single lesion (plasmacytoma) or as multiple lesions (multiple myeloma). METHODS: Paraffin-embedded tissue blocks of patients microscopically diagnosed with plasma cell neoplasms in the jaws were retrieved from five pathology files. Data including clinical, radiographic, microscopic and immunohistochemical findings, treatment employed and follow-up status were retrieved from the pathology reports. RESULTS: Fifty-two cases were retrieved (mean age: 59.4 years) without sex predilection. The mandible was the most affected site (67.3%), usually associated with pain and/or paresthesia (53.8%). Lesions in other bones besides the jaws were reported for 24 patients (46.2%). Radiographically, tumours usually presented as poorly defined osteolytic lesions with unilocular or multilocular images, while microscopy revealed diffuse proliferation of neoplastic plasma cells with nuclear displacement and abundant eosinophilic cytoplasm. Two cases were classified as anaplastic, and amyloid deposits were found in two other cases. Immunohistochemistry was positive for plasma cell markers and negative for CD20 and CD3, and monoclonality for kappa light chain predominated. The overall survival rate after 5 years of follow-up was 26.6%. CONCLUSION: Plasma cell neoplasms are aggressive tumours with a poor prognosis and involvement of the jaws may be the first complaint of the patient. Thus, oral pathologists, head and neck surgeons and dentists should be aware of their clinical, radiographic and microscopic manifestations.

Oral focal mucinosis: A multi-institutional study and literature review.

BACKGROUND: Oral focal mucinosis (OFM) is a rare benign condition of unknown etiology, considered the oral counterpart of cutaneous focal mucinosis. We report the clinicopathologic features of 21 cases of OFM in conjunction with a review of the literature. METHODS: Clinical data were collected from the records of five oral and maxillofacial pathology services. All cases were evaluated by hematoxylin and eosin staining, histochemistry, and immunohistochemistry (vimentin, S-100, α-SMA, CD34, and mast cell). RESULTS: The series comprised 14 females (66.7%) and seven males (33.3%), with a mean age of 48.2 ± 20.7 years (range: 8-77 years) and a 2:1 female-to-male ratio. Most of the lesions affected the gingiva (n = 6, 28.6%) and presented clinically as asymptomatic sessile or pedunculated nodules with fibrous or hyperplasic appearance. All cases were negative for S-100 protein, CD34, and α-SMA and positive for Alcian blue staining. Conservative surgical excision was the treatment in all cases, and there was only one recurrence. CONCLUSION: OFM is a rare benign disorder that is often clinically misdiagnosed as reactive lesions or benign proliferative processes. Dermatologists and pathologists should consider OFM in the differential diagnosis of soft tissue lesions in the oral cavity, mainly located in the gingiva.

Analysis of immediate use of sunscreen after microneedling.

INTRODUCTION: Microneedling promotes skin microlesions that lead to an inflammatory process, increasing cell proliferation, cell metabolism, and synthesis of collagen and elastin, therefore restoring skin integrity. OBJECTIVE: This study aims to investigate the differences between the physical and the physical-chemical sunscreen application after microneedling, assessed through histological analysis. METHOD: This was a two-phase study. The first phase investigated the physical and physical-chemical sunscreen penetration mixed with India ink through histological analysis. The sunscreens were applied after the microleakage in vivo on the skin of a volunteer who underwent abdominoplasty 24 hours after the procedure. Histological analyses were carried out using optical and electron microscopy. The second phase analysed the skin reactions with the use of physical sunscreen after different microneedling treatments. The sample consisted of 30 volunteers distributed into three groups: G1 received the "Roller" microneedling, G2 received pen micropuncture treatment, and G3 received the fractional radiofrequency treatment. RESULTS: The histological analyses of the first phase indicated that the physical-chemical protection sunscreen penetrated more deeply, and pigment was found among the collagen fibres and the dermal fibroblast cytoplasm in comparison to the physical protection sunscreen, which had the pigment confined exclusively in the superficial epidermis layer. The second phase results demonstrated that the use of the physical protection sunscreen after the different microneedling techniques showed no adverse reactions such as itching, pain or soreness, and the hyperaemia. CONCLUSION: The proposed intervention showed that the use of physical protection sunscreen after different microneedling procedures is safe.

Prognostic importance of RUNX1 expression for head and neck adenoid cystic carcinoma.

OBJECTIVE: In the present study, we aimed to investigate the prognostic value of RUNX1 expression in 76 patients with adenoid cystic carcinoma (ACC). MATERIALS AND METHODS: All cases were arranged in tissue microarray blocks and submitted to immunohistochemistry against RUNX1. These results were statistically correlated with clinicopathologic features, including age, gender, tumour site, tumour size, lymph node status, AJCC clinical stage, distant metastasis, treatment, recurrences, follow-up, histologic pattern, vascular and neural invasion, all of which obtained from patient's medical records. RESULTS: RUNX1 was expressed in the nuclei of tumour cells, with a mean of 18.1% of positivity. Nuclear RUNX1 expression was significantly associated with AJCC clinical stage (p < .0001), solid histologic pattern (p < .0001), vascular invasion (p < .0001) and presence of local recurrence (p < .0001). Using univariate and multivariate analyses, RUNX1 nuclear expression was significantly associated with a lower disease-free survival (p < .0001 and p = .028, respectively) and disease-specific survival (p < .0001 and p = .018, respectively) rates. CONCLUSION: In summary, RUNX1 nuclear expression may represent an indicator of unfavourable outcome for patients affected by head and neck ACC.

Expression of mitochondrial dynamics markers during melanoma progression: Comparative study of head and neck cutaneous and mucosal melanomas.

BACKGROUND: Head and neck mucosal melanomas (MMs) are rare tumors with adverse outcomes and poorer prognoses than their more common cutaneous counterparts (cutaneous melanomas-CMs). Few studies have compared the expression of mitochondrial dynamic markers in these tumors. This study aimed to assess the correlations of mitochondrial markers with melanoma progression and their potential as predictors of lymph node involvement and distant metastasis. METHODS: Immunohistochemistry against anti-mitochondrial (AMT), dynamin-related protein 1 (DRP1), mitochondrial fission protein 1 (FIS1), mitofusin-1 (MFN1), and mitofusin-2 (MFN2) antibodies was performed in 112 cases of head and neck CM and MM. A Cox regression multivariate model was used to assess the correlation of AMT, FIS1, and MFN2 expressions considering the risk for nodal and distant metastasis. RESULTS: All markers studied presented higher staining in tumor cells than normal adjacent tissues. Higher mitochondrial content was observed in MM than in CM, and it was significantly associated with nodal metastasis in oral melanomas. Both FIS1 and DRP1 expressions were related to advanced Clark's levels in CM, and they were overexpressed in oral melanomas. Moreover, increased immunoexpression of MFN2 was significantly associated with a higher risk of metastasis in CM, and it was also overexpressed in sinonasal melanomas. CONCLUSIONS: Our results suggest that mitochondrial fission and fusion processes can play an important role during multiple stages of tumorigenesis and the development of nodal and distant metastasis in cutaneous and mucosal melanomas.

Effects of the extracorporeal shock wave therapy on the skin: an experimental study.

Extracorporeal shock wave therapy (ESWT) has been extensively studied for its multiple biological properties, and although it is widely applied in esthetical procedures, little is known about its effects on the epidermis and dermis. In this study, a histological and immunohistochemical study of the effects of ESWT was performed on rat skin. Forty-five female rats were treated with one or two sessions of ESWT and sacrificed on days 1, 7, 14, and 21 after treatment. The samples were histologically processed and then morphometric analyses were performed to assess the epidermis, dermis, and subcutaneous fat tissue thickness. Immunohistochemical reactions were also performed against the antibodies: basic fibroblastic growth factor (FGF2), its receptor (FGFR1), and α-smooth muscle actin. Slides were scanned and digitally assessed, to determine the microvessel density (MVD) and digital scoring of the immunohistochemical staining. The results showed that ESWT produced a significantly higher collagen content, MVD, and epidermis and dermis thickness than the control, non-treated group. Both in epidermis and dermis, FGF2 was overexpressed in the ESWT-treated groups, whereas FGFR1 was increased only in the group treated with two ESWT sessions at 21-days post-treatment. The ESWT-treated groups have also shown diminished thickness of subcutaneous fat tissue. In conclusion, ESWT induces neocollagenesis and neoangiogenesis, and upregulates the FGF2 expression, particularly in the groups treated with two sessions. Furthermore, it was demonstrated that overexpression of FGF2 on skins treated with ESWT seems to be a key role on its mechanism of action.

Agrin has a pathological role in the progression of oral cancer.

BACKGROUND: The extracellular matrix modulates the hallmarks of cancer. Here we examined the role of agrin-a member of this matrix-in progression of oral squamous cell carcinoma (OSCC). METHODS: We evaluated the immunohistochemical expression of agrin in OSCC and dysplasias. Benign lesions were used as control. In subsequent experiments, we investigated whether the silencing of agrin interferes with tumour expansion both in vitro as well as in vivo. To gain insights into the role of agrin, we identified its protein network (interactome) using mass spectrometry-based proteomics and bioinformatics. Finally, we evaluated the clinical relevance of agrin interactome. RESULTS: Agrin was elevated in malignant and premalignant lesions. Further, we show that agrin silencing interferes with cancer cell motility, proliferation, invasion, colony and tumour spheroid formation, and it also reduces the phosphorylation of FAK, ERK and cyclin D1 proteins in OSCC cells. In orthotopic model, agrin silencing reduces tumour aggressiveness, like vascular and neural invasion. From a clinical perspective, agrin contextual hubs predict a poor clinical prognosis related with overall survival. CONCLUSIONS: Altogether, our results demonstrate that agrin is a histological marker for the progression of oral cancer and is a strong therapeutic target candidate for both premalignant and OSCC lesions.

Prognostic importance of FGF2 and FGFR1 expression for patients affected by ameloblastoma.

BACKGROUND: Fibroblast growth factor 2 (FGF2) and FGF receptor 1 (FGFR1) have been investigated in different human neoplasms and were shown to play important roles in the pathogenesis of these diseases; however, very few are known regarding their prognostic importance in the context of ameloblastoma. Therefore, the aim of this study was to investigate whether the expression of FGF2 and FGFR1 is associated with ameloblastoma clinical behavior. METHODS: Fifty-eight cases of ameloblastoma arranged in tissue microarray were submitted to immunohistochemistry against FGF2 and FGFR1. Clinicopathological parameters regarding sex, age, tumor size, duration and location, treatment, recurrences, radiographic features, cortical disruptions, and follow-up data were obtained from patients' medical records and correlated with the molecules expression. Univariate and multivariate Cox regression analyses were used to investigate the prognostic potential of the biomarkers. RESULTS: Forty-four cases (75.9%) exhibited cytoplasmic positivity for FGF2 in central and peripheral epithelial cells, 46 of 58 (79.3%) showed FGFR1 cytoplasmic positivity predominantly in the columnar peripheral cells, and 43 cases (74.1%) were positive for both. Expression of FGF2 and FGF2 + FGFR1 was associated with tumor recurrences (P = .05). However, univariate and multivariate analyses did not demonstrate a significant influence of FGF2, FGFR1, or FGF2 + FGFR1 in the 5-year disease-free survival (DFS) rate (P = .27, P = .33, and P = .25, respectively). CONCLUSION: Cytoplasmic expression of FGF2 and FGF2 + FGFR1 is associated with ameloblastoma recurrence, but FGF2 and FGFR1 are not determinants of a lower DFS.

Effect of low-level laser therapy on angiogenesis and matrix metalloproteinase-2 immunoexpression in wound repair.

Low-level laser therapy (LLLT) induces anti-inflammatory and angiogenic activities in wound healing. However, the mechanism of action and optimal parameters require further clarification. In this study, we investigated the effects of LLLT on wound healing matrix metalloproteinase (MMP)-2 immunoexpression and angiogenic processes. Twenty female Wistar rats were randomly divided into four groups (n = 5) according to the treatments as follows. CG7 and CG14 were control groups at days 7 and 14, respectively, which received physiological saline (0.9 % NaCl daily). LG7 and LG14 were laser therapy groups at days 7 and 14, respectively, which received two (LG7) or four (LG14) LLLT applications (40 mW; 660 nm; 4 J/cm2). A dorsal skin sample in the wound area (measuring 2 cm2) was removed after the experimental period, and then the animals were euthanized. The specimens were processed for qualitative and quantitative histological analyses and measurement of MMP-2 expression in the dermis and epidermis. A persistent crust and moderate number of inflammatory cells were found in CG7 and CG14 groups. In the LG14 group, wounds demonstrated complete re-epithelization at the remodeling phase. Angiogenesis and MMP-2 expression were higher in LLLT-treated groups, particularly the LG14 group, which correlated according to the Spearman correlation test. LLLT improves wound healing by enhancing neocollagenesis, increasing the amount of new vessels formed in the tissue (neoangiogenesis), and modulating MMP-2 expression. Epidermal overexpression of MMP-2 was correlated to angiogenic processes.

Radiofrequency treatment induces fibroblast growth factor 2 expression and subsequently promotes neocollagenesis and neoangiogenesis in the skin tissue.

Radiofrequency (RF) treatment appears to be involved in production of new collagen fibrils and the improvement of existing collagen structures; however, the molecular bases of the effect of non-invasive RF on the skin tissue have not been fully elucidated. This study reports the effects of RF associated or not with hydrolyzed collagen (HC) in the skin tissue. Wistar rats were randomly divided into four groups, according to the treatment received: control group (G1, n = 5), no treatment; subjects in group G2 (n = 5) were treated with HC; and capacitive RF was applied to the back of each subject in G3 (n = 5) and RF associated with HC in G4 (n = 5). Biopsies were taken 30 days after treatment and then were histologically processed and studied for inflammatory cell counting, collagen content, and morphometry. In addition, FGF2, CD105, and COX-2 expression was assessed by immunohistochemical staining. The most relevant changes were the increase in cellularity and accumulation of intercellular substance in RF-treated animals (G3 and G4). The greatest dermis thickness rate was observed in G4, followed by G3 and G2 (p < 0.05). RF-treated skins (G3 and G4) exhibited a significant overexpression of FGF2 (p < 0.0001) and increased microvessel density (p < 0.0001) in comparison with G1 and G2. Moreover, the amount of COX-2 was significantly higher (p < 0.0001) in dermis of RF-treated areas compared to G1 and G2, and demonstrated differences in G3 (RF) compared to G4 (RF + HC) (p < 0.0001). Our results suggests that RF treatment associated or not with HC induces FGF2 overexpression, promotes neoangiogenesis and modulates the COX-2 expression, subsequently promotes neocollagenesis, and increased thickness rate of dermis.