Serosurvey of Coxiella burnetii in Descendants of Former Black Slaves (Quilombola Communities) of Southern Brazil.

Brazilian descendants of former Black-slave (quilombola) communities have been predisposed to several zoonotic diseases due to social vulnerability, characterized by subsistence and close contact with livestock and companion animals. Accordingly, the present study has assessed anti-Coxiella burnetii antibodies in 200 individuals and 20 dogs from four quilombola communities located in Paraná State, southern Brazil. Serum samples were tested by indirect immunofluorescence assay (IFA) using in-house and commercial diagnostic protocols, with analysis of seropositive titers and antibody type. Fisher's exact test was used to compare seropositivity to C. burnetti with binary variables, with variables with three or more possible responses submitted to logistic regression. In total, 44/200 (22%; 95% CI 16.82-28.24) people tested positive, and 4.5% had titers higher than 128, indicating a recent onset of C. burnetii infection. Seropositive individuals were statistically associated with the Limitão community (p = 0.0013), urban workers as occupations (p = 0.0475), consumption of undercooked meat (p = 0.0159), and contact with animal abortion (p = 0.0276). No seropositivity association was found for age, sex, education, habit of entering forest areas, consumption of game meat, consumption of raw milk, flea and tick bites, dog contact, or history of female miscarriage. Only one of 20 dogs was seropositive with a titer of 128, probably related to an acute animal infection. Despite the prevalence here being higher than previous Brazilian reports, including with symptomatic populations, the results were within range for worldwide outbreaks and occupational risk populations. To the reader's knowledge, this is the first human survey of Q fever in southern Brazil and should be considered a warning for C. burnetii in vulnerable populations, particularly Quilombola communities.

Platelet indices and angiogenesis markers in hypertensive disorders of pregnancy.

INTRODUCTION: Activated platelets exert a key role in the pathogenesis of preeclampsia (PE). There is evidence of distinctive patterns of platelet indices in PE in comparison to healthy pregnancies, therefore these indices can be potential tools for PE detection, risk stratification, and management. Considering the vascular aspects of its pathophysiology, PE is characterized by the increased levels of soluble FMS-like tyrosine kinase-1 (sFlt-1) an antiangiogenic factor, and reduced placental growth factor (PlGF), a proangiogenic factor. This study aimed to assess the platelet indices in hypertensive disorders of pregnancy (HDP) and its correlation with angiogenesis-related biomarkers. METHODS: The groups for the study were: control (n = 114); gestational hypertension; (n = 112), and PE (n = 42). The platelet indices included were platelet counts (PLT-I and PLT-F), mean platelet volume (MPV), platelet distribution width (PDW), plateletcrit (PCT), platelet large cell ratio (P-LCR), and immature platelet fraction (IPF# and IPF%). Serum levels of sFlt-1 and PlGF were assessed. RESULTS: PLT-I, PLT-F, and PCT% were lower in PE, while MPV, PDW, P-LCR, IPF%, and IPF# were increased. The parameter MPV presented the best performance for the discrimination of PE. There was a moderate positive correlation between sFlt-1 levels and MPV, PDW, and P-LCR. CONCLUSION: Platelet indices can be potentially applied as additional tools for the diagnosis and management of HDP. Activated platelets may act as an extra source of sFlt-1 in PE.

One health approach to toxocariasis in quilombola communities of southern Brazil.

BACKGROUND: Toxocariasis has been listed among the most neglected parasitic diseases worldwide, with approximately one fifth of the global population exposed, particularly those living under poverty. In Brazil, communities of descendants of enslaved blacks (quilombola) have historically had some of the highest rates of vulnerability and poverty, characterized by lack of health assistance, poor quality of life, and nutritional insecurity. METHODS: A cross-sectional sampling of quilombola individuals living in four communities of southern Brazil, as well as their dogs and the soil, was carried out from December 2021 to March 2022. Sociodemographic and other information such as water source, alimentary habits, and dog and cat ownership were gathered using a semi-structured questionnaire for assessing toxocariasis risk factors. Human serum samples were tested by ELISA for anti-Toxocara spp. IgG antibody detection was carried out on dog feces and hair, and soil samples were surveyed for presence of Toxocara spp. eggs. RESULTS: Overall, 172/208 individuals (82.7%, 95% CI = 77.0-87.2) were seropositive, the highest seroprevalence rate to date in Brazil. Male gender (P = 0.029), educational level (P = 0.026), and drinking water source (P = 0.043) were associated with seropositivity by univariate analysis. Final logistic regression revealed increased odds (P = 0.017, OR = 7.6, 95% CI = 1.5-42.7) to have seropositivity in individuals > 50 years old (< 10 years old). As expected, individuals with soil contact were more likely seropositive (P = 0.038, OR = 4.4, 95% CI = 1.1-18.8). Although retrieved in only 5/96 (5.2%) dog feces, Toxocara spp. eggs were found in 18/60 (30.0%) soil samples. CONCLUSIONS: The high vulnerability and seroprevalence observed in quilombola communities clearly demand a One Health approach for detection, monitoring, and prevention of infection by Toxocara spp. in both human and dog populations.

One Health Approach in Serosurvey of Toxoplasma gondii in Former Black Slave (Quilombola) Communities in Southern Brazil and Among Their Dogs.

Brazilian quilombos are rural semi-isolated remnant communities of former black slaves and their descendants who traditionally maintained themselves through archaic subsistence livestock and agriculture practices and historically lacked specific public health policies. Although such individuals and their dogs may be exposed to zoonotic pathogens such as Toxoplasma gondii, no study to date has assessed these human-animal populations together. Populations in four different Brazilian quilombos in southern Brazil were evaluated. Overall, 93/208 people (44.7%) and 63/100 dogs (63.0%) were seropositive for IgG anti-T. gondii antibodies by indirect immunofluorescent antibody test (IFAT), 4/208 (1.9%) human samples seropositive for IgM anti-T. gondii antibodies, with a human-dog seropositivity ratio for IgG of 0.71. Quilombola individuals ingesting game meat were 2.43-fold more likely (95% CI: 1.05-5.9) to be seropositive. No risk factors were associated with seropositivity among dogs, thus suggesting that their exposure to T. gondii was random. Surprisingly, our research group had previously found an inverted human-dog ratio for T. gondii seropositivity of 2.54 in the urban area of a nearby major city. Because consumption of raw/undercooked game meat by quilombola individuals may have contributed to higher exposure, higher overall seroprevalence among dogs may have also indicated interaction with wildlife. Although these dogs may hunt wildlife without their owners' awareness, the higher dog seropositivity may also be related to feeding from discarded food in the community or backyard livestock animals and drinking surface water contaminated with oocysts. Thus, wildlife cannot be singled out as the reason, and future studies should consider sampling water, soil, wildlife, and livestock tissues, to fully establish the source of infection in dogs herein.

One Health at gunpoint: Impact of wild boars as exotic species in Brazil - A review.

Wild boars have been listed among the 100 most invasive species worldwide, spreading impacts to all continents, with the exception of Antarctica. In Brazil, a major source of introduction was a commercial livestock importation for exotic meat market, followed by successive escapes and releases to natural ecosystems. Currently found in all six Brazilian biomes, with reports in 11 Brazilian states, wild boars have invaded natural and agricultural areas. Wild boars have been reportedly indicated as hosts and reservoirs of several zoonotic diseases in Brazil, including toxoplasmosis, salmonelosis, leptospirosis, brucellosis, tuberculosis, trichinellosis, and hepatitis E. Wild boars have been also associated with Brazilian spotted fever and rabies, infected while providing plentiful exotic blood supply for native ticks and hematophagous bats. Due to their phylogenetic proximity, wild boars may present ecological niche overlapping and direct disease risk to native white-lipped and collared peccaries. Moreover, wild boars may post an economical threat to Brazilian livestock industry due to restrictive diseases such as Aujeszky, enzootic pneumonia, neosporosis, hemoplasmosis, and classic swine fever. Finally, wild boars have directly impacted in environmentally protected areas, silting up water springs, rooting and wallowing native plants, decreasing native vegetal coverage, disbalancing of soil components, altering soil structure and composition. Wild boar hunting has failed as a control measure to date, according to the Brazilian Ministry of Environment, due to private hunting groups mostly targeting males, intentionally leaving females and piglets alive, disseminating wild boar populations nationwide. Meanwhile, non-government animal welfare organizations have pointed to animal cruelty of hunting dogs and wild boars (and native species) during hunting. Despite unanimous necessity of wild boar control, eradication and prevention, methods have been controversial and should focus on effective governmental measures instead occasional game hunting, which has negatively impacted native wildlife species while wild boars have continuously spread throughout Brazil.

Overview of Perinatal Palliative Care in Brazil

Abstract Significant attention to palliative care in terminally ill patients has only been effective in Brazil since the year 2000, although there have been isolated actions since the 1980s. When the case involves fetuses or neonates unable to cure, communication and care with the family members only received attention and effective organization starting in 2017. Notably in the years 2015 and 2016 there was an epidemic of microcephaly and along with the persistent crisis of drug users has raised the indices of malformations to a level higher than 3 % of the world average. Here we aim the evaluation of: a) social, educational and spiritual profile of the mothers; b) structure of the specific teams related to palliative care in neonatology; c) recommendations and protocols currently used in the country. The method used is an electronic retrospective on databases and government data; evaluation of the location and composition of palliative care teams in the country. The data found clearly point out that for Brazilian women, the characteristics of regionality in the country, educational level, religiousness and quality of life directly influence pregnancy and the acceptance or not of the possibility of death, directly influencing perinatal palliative care, which, by the way, is still developing methodologies for this type of action.

Serosurvey of anti-Leishmania (Leishmania) infantum antibodies in hunting dogs and hunters in Brazil.

BACKGROUND AND AIM: Although wild boar hunting activities and the hunting dog trade in the Atlantic Forest and Cerrado biomes of Brazil overlap both with endemic and with non-endemic areas for visceral leishmaniasis, no study to date has focused on Leishmania spp. exposure among hunting dogs and hunters. The aim of the present study was to assess the presence of Leishmania spp. antibodies in hunting dogs and hunters in different anthropized areas of two Brazilian biomes. MATERIALS AND METHODS: Blood samples were collected from 170 hunting dogs and 46 hunters between October 2016 and May 2018. The presence of antibodies against Leishmania spp. in hunting dogs was screened through a dual-path platform immunochromatographic test (DPP rapid test; Bio-Manguinhos/Fundação Oswaldo Cruz, Rio de Janeiro, Brazil) and in hunters through an rK39-based rapid immunochromatographic test. Both tests were used in accordance with Brazilian Ministry of Health recommendations. RESULTS: Overall, although antibodies were detected through the immunochromatographic test in 3/170 (0.02%) of these female asymptomatic hunting dogs, all living in anthropized areas of the Atlantic Forest biome in South Brazil, no sample was confirmed through the enzyme-linked immunosorbent assay. All the hunters were non-reactive in the rapid immunochromatographic test. CONCLUSION: Our study on three suspicious hunting dogs has suggested that Leishmania (Leishmania) infantum may circulate both in endemic and non-endemic areas in Brazil. In addition, a high rate of hunting dog replacement due to death and trade may have led to less chance of infection and transmission between animals and between animals and humans, which would corroborate the outcomes reported here. Further studies should be conducted to fully establish whether hunting dogs and hunters may be used as sentinels in other areas endemic for Leishmania spp.

Risk factors associated with ticks and Rickettsia spp. exposure in wild boars (Sus scrofa), hunting dogs, and hunters of Brazil.

BACKGROUND AND AIM: Wild boars have recently been implicated as the maintainers and carriers of Amblyomma spp. ticks, which are essential for Rickettsia spp. transmission. Consequently, wild boar hunting may increase the risk of tick exposure and subsequent human tick-borne infection and disease. Therefore, this study was conducted to evaluate the risk factors for ticks and Rickettsia spp. exposure in wild boars, hunting dogs, and hunters in Brazilian biomes. MATERIALS AND METHODS: The statistical relationship of Rickettsia spp. antibodies were evaluated using the Chi-square test in 80 wild boars, 170 hunting dogs, and 49 hunters. RESULTS: The only statistically significant difference in seropositivity found in this study was between male and female wild boars (p=0.034), probably associated with in-park exposure to Amblyomma brasiliense infected with Rickettsia spp. CONCLUSION: The absence of statistical differences in the associated risk factors for hunting dogs and hunters may indicate a random exposure to Rickettsia spp.

Seroprevalence of Anti-Brucella spp. Antibodies in Wild Boars (Sus scrofa), Hunting Dogs, and Hunters of Brazil.

All 86 wild boars (Sus scrofa), 170 hunting dogs, and 49 hunters sampled from three Brazilian regions were seronegative to Brucella spp. by the standard tube agglutination and 2-mercaptoethanol tests, suggesting a low circulation of Brucella spp. in wild boars, hunting dogs, and hunters in such areas.

Silencing of Transposable Elements Mediated by 5-mC and Compensation of the Heterochromatin Content by Presence of B Chromosomes in Astyanax scabripinnis.

The way in which transcriptional activity overcomes the physical DNA structure and gene regulation mechanisms involves complex processes that are not yet fully understood. Modifications in the cytosine-guanine sequence of DNA by 5-mC are preferentially located in heterochromatic regions and are related to gene silencing. Herein, we investigate evidence of epigenetic regulation related to the B chromosome model and transposable elements in A. scabripinnis. Indirect immunofluorescence using anti-5-mC to mark methylated regions was employed along with quantitative ELISA to determine the total genomic DNA methylation level. 5-mC signals were dispersed in the chromosomes of both females and males, with preferential accumulation in the B chromosome. In addition to the heterochromatic methylated regions, our results suggest that methylation is associated with transposable elements (LINE and Tc1-Mariner). Heterochromatin content was measured based on the C-band length in relation to the size of chromosome 1. The B chromosome in A. scabripinnis comprises heterochromatin located in the pericentromeric region of both arms of this isochromosome. In this context, individuals with B chromosomes should have an increased heterochromatin content when compared to individuals that do not. Although, both heterochromatin content and genome methylation showed no significant differences between sexes or in relation to the occurrence of B chromosomes. Our evidence suggests that the B chromosome can have a compensation effect on the heterochromatin content and that methylation possibly operates to silence TEs in A. scabripinnis. This represents a sui generis compensation and gene activity buffering mechanism.

Evaluation of Depressive and Anxious Behavior with the Use of Propranolol in Melanoma-Bearing Mice

HIGHLIGHTS: Tumor progression and anxiety and depression behaviors under evaluation during propranolol use in murine melanoma. Evaluation of anxiety and depression through forced swimming behavior tests, elevated plus maze, open field and marble-burying test.

Abstract Melanoma, a severe form of skin cancer, has rapid growth and has been prone to behavioral disorders that worsen the patient's prognosis and survival. Among these psychic disorders can occur anxiety and depression, in addition to cognitive deficit. In order to try to elucidate the neuropsychological disorders that occur in melanoma, the objective of this study was to evaluate propranolol in tumor progression and in anxious and depressive behaviors in an animal model with melanoma. B16F10 cells were injected into C57BL6/J mice subsequently treated with propranolol at doses of 1.43 mg/kg and 5.71 mg/kg and evaluated for tumor growth and in open field, forced swimming, elevated plus maze and marble-burying test at initial time and consolidated tumor. As a result, the group treated with propranolol at a dose of 5.71 mg/kg showed less tumor growth. In the initial behavioral tests, melanoma altered the animals' motility, but anxious behavior was not detected. Depressive behavior was detected in the forced swimming test in the two doses of the treatment used. When taking time with consolidated tumor, there was a reduction in the locomotor activity of the animals in the open field test, impairing the analysis of anxious and depressive behavior. The data suggest that there was a reduction in the progression of melanoma, there was no anxious behavior in the animals, only the depressive behavior and the use of propranolol did not improve the evaluated behavior.

Ações extensionistas na prevenção, cuidados e combate à pandemia por Coronavírus nas divisas do Paraná / Acciones extensionistas para prevenir, cuidar y combatir pandemia por Coronavirus en las fronteras de Paraná / Extensionist actions to prevent, care and combat pandemic by Coronavirus on the borders of Paraná

Objetivo: descrever as atividades extensionistas de prevenção, cuidados e combate à pandemia por coronavírus nas divisas do Paraná. Método: estudo observacional, descritivo de dados provenientes das Ações Extensionistas Prevenção, Cuidados e Combate à Pandemia do Novo Coronavírus - Atenção às divisas rodoviárias do Estado, realizadas de abril a junho de 2020. Resultados: o programa contou com três ações diferentes, sendo desenvolvidas por uma equipe multiprofissional: ações educativas no pedágio, no contêiner da saúde, na ronda ao longo da rodovia e no projeto Saúde na Estrada. Conclusões: a ação possibilitou o trabalho de prevenção e promoção de saúde à população, além de proporcionar aos profissionais de saúde uma visão ampliada do trabalho em equipe e de um problema de saúde pública.(AU)

Objective: to describe extensionist actions of prevention, care and cope of pandemic by coronavirus on the borders of Paraná. Method: observational study, descriptive of data from the Extensionist Actions to Prevent, Care and Combat the New Coronavirus Pandemic - Attention to the road boundaries of the State, from April to June 2020. Results: the program had three different actions, being developed by a multiprofessional team: educational actions at the toll, at a mobile outpatient clinic, at rounds on the road and at Health on Road project. Conclusions: the action made it possible to prevent and promote health to the population, besides provided an expanded view of teamwork for professionals and a public health problem.(AU)

Objetivo: describir extensionistas acciones de prevención, cuidado y frente al pandemia por el coronavirus en las fronteras de Paraná. Método: estudio observacional, descriptivo de los dados del Acciones extensionistas de prevención, atención y combate de pandemia por el nuevo coronavirus - Atención a los límites de las carreteras del Estado, de abril a junio de 2020. Resultados: el programa tenía tres acciones diferentes desarrolladas por un equipo multiprofesional: acciones educativas en el peaje, en el contenedor de salud, en la ronda a lo largo de la carretera y en el proyecto Saúde na Estrada. Conclusiones: la acción permitió el trabajo de prevención y promoción de la salud de la población, además de proporcionar a los profesionales de la salud una visión ampliada del trabajo en equipo y un problema de salud pública.(AU)

Assessment of Experimental Models for Obtaining Adipose-Derived Mesenchymal Stem Cells

Abstract Creating experimental models for obtaining stem cells from adipose tissue is necessary to elucidate their peculiar features. Objective: This study proposed a reliable reproducible and consistent experimental model for obtaining mesenchymal stem cells from adipose tissue. Material and Method: Lines of New Zealand rabbits, Wistar rats and CaviaPorcellus guinea pigs (4 animals per species) were used. Fatty tissue mesenchymal stem cells were removed from dorsal, epididymal and inguinal regions. Percentage viable cells and percentage cells expanded and submitted to chondrogenic differentiation were compared by animal species and collection site. Results: Chondrogenic differentiation occurred in a similar manner across all samples, independently of animal species or collection site. Among samples assessed, the inguinal region of rats yielded the highest percentage of viable and expanded cells. Conclusion: A reliable, reproducible and consistent model for obtaining mesenchymal stem cells was produced. Of the several variables analysed, the best results were obtained from the inguinal region of the rat.

Gut: Key Element on Immune System Regulation

Abstract The gut is the main organ that mediates the contact between antigens with our organism, controlling the immune response against environmental factors, such as microbiota and food. Innate lymphoid cells participate in the gut-associated lymphoid tissue (GALT) maturation during the prenatal and early postnatal periods. After birth, breast milk provides the essential elements for the continuity of development of this tissue, leading to structural changes and healthy microbiota installation. The microbiota participates in the organogenesis of the GALT, as in the formation of intestinal villi, stimulating the proliferation of stem cells and maintaining the integrity of epithelial barrier. Foods are also involved in maturation of the GALT, where the protein source depletion reduced the number of resident lymphocytes. This unique microenvironment present in the intestinal lamina propria (LP) and mesenteric lymph nodes (mLN) induce tolerance to innocuous antigens from the diet, known as Oral Tolerance. Antigens sampled by intestinal epithelium cells are transferred to specialized dendritic cells, residing in the LP, which migrate to the mesenteric lymph nodes where they participate in the induction of regulatory T cells (Treg). Understanding these phenomena may establish the intestinal mucosa as a tool in therapy of inflammatory bowel diseases and immunological disorders.

Bovine serum albumin nanoparticles improve the antitumour activity of curcumin in a murine melanoma model.

Curcumin is a natural compound presenting important antitumour activity. However, due to its low aqueous solubility, instability at physiological pH, and low oral bioavailability, its clinical use is limited. Bovine serum albumin (BSA) nanoparticles have been used as drug carriers to improve the drug properties. In this work, curcumin-loaded BSA nanoparticles were developed and the in vitro cytotoxicity over murine melanoma cells and the in vivo antitumour activity in a murine melanoma model were assessed. Nanoparticles presented 150 nm, polydispersity index of 0.16, negative zeta potential, and 45% of curcumin encapsulation efficiency. Curcumin release from nanoparticles was slow and diffusion dependent. In the cytotoxicity assay, free curcumin was more efficient than curcumin-loaded nanoparticles, probably due to the prolonged curcumin release from nanoparticles. However, in a murine melanoma model, curcumin-loaded nanoparticles presented higher antitumour efficiency than free curcumin. BSA nanoparticles are efficient curcumin carriers that may have relevant applications in melanoma treatment.

High doses of laser phototherapy can increase proliferation in melanoma stromal connective tissue.

It is well established that laser phototherapy (LP) is contraindicated directly over cancer cells, due to its bio modulatory effects in cell and blood vessel proliferation. The aim of the present study was to analyze the influence of typical low-level laser therapy (LLLT) and high intensity laser therapy (HILT) and an in-between dose of 9 J on collagen fibers and blood vessels content in melanoma tumors (B16F10) implanted in mice. Melanoma tumor cells were injected in male Balb C mice which were distributed in four groups: control (no irradiated) or irradiated by 3, 9, or 21 J (150; 450, or 1050 J/cm2). LP was performed in daily sessions for 3 days with a InGaAlP-660 nm (mean output: 50 mW, spot size: 2 mm2). Tumor volume was analyzed using (1) picrosirius staining to quantify collagen fibers content and (2) Verhoeff's method to quantify blood vessels content. Tumor growth outcome measured in the 3-J group was not significantly different from controls. Nine and 21-J groups, presented significant and dose-dependent increases in tumor volume. Quantitative analysis of the intensity of collagen fibers and their organization in stroma and peri-tumoral microenvironment showed significant differences between irradiated and control group. Blood vessels count of 21-J group outnumbered the other groups. High doses (≥ 9 J) of LP showed a dose-dependent tumor growth, different collagen fibers characteristics, and eventually blood vessel growth, while a typical LLLT dose (3 J) appeared harmless on melanoma cell activity.

Laser photobiomodulation in pressure ulcer healing of human diabetic patients: gene expression analysis of inflammatory biochemical markers.

Pressure ulcers (PU) are wounds located mainly on bone surfaces where the tissue under pressure suffers ischemia leading to cellular lesion and necrosis , its causes and the healing process depend on several factors. The aim of this study was evaluating the gene expression of inflammatory/reparative factors: IL6, TNF, VEGF, and TGF, which take part in the tissue healing process under effects of low-level laser therapy (LLLT). In order to perform lesion area analysis, PUs were photographed and computer analyzed. Biochemical analysis was performed sa.mpling ulcer border tissue obtained through biopsy before and after laser therapy and quantitative real-time PCR (qRT-PCR) analysis. The study comprised eight individuals, mean age sixty-two years old, and sacroiliac and calcaneous PU, classified as degree III and IV according to the National Pressure Ulcer Advisory Panel (NPUAP). PUs were irradiated with low-level laser (InGaAIP, 100 mW, 660 nm), energy density 2 J/cm2, once a day, with intervals of 24 h, totaling 12 applications. The lesion area analysis revealed averaged improvement of the granulation tissue size up to 50% from pre- to post-treatment. qRT-PCR analysis revealed that IL6 values were not significantly different before and after treatment, TNF gene expression was reduced, and VEFG and TGF-ß gene expression increased after treatment. After LLLT, wounds presented improvement in gross appearance, with increase in factors VEFG and TGF-ß, and reduction of TNF; despite our promising results, they have to be analyzed carefully as this study did not have a control group.

High doses of laser phototherapy can increase proliferation in melanoma stromal connective tissue

It is well established that laser phototherapy (LP) is contraindicated directly over cancer cells, due to its bio modulatory effects in cell and blood vessel proliferation. The aim of the present study was to analyze the influence of typical low-level laser therapy (LLLT) and high intensity laser therapy (HILT) and an in-between dose of 9 J on collagen fibers and blood vessels content in melanoma tumors (B16F10) implanted in mice. Melanoma tumor cells were injected in male Balb C mice which were distributed in four groups: control (no irradiated) or irradiated by 3, 9, or 21 J (150; 450, or 1050 J/cm2). LP was performed in daily sessions for 3 days with a InGaAlP—660 nm (mean output: 50 mW, spot size: 2 mm2). Tumor volume was analyzed using (1) picrosirius staining to quantify collagen fibers content and (2) Verhoeff’s method to quantify blood vessels content. Tumor growth outcome measured in the 3-J group was not significantly different from controls. Nine and 21-J groups, presented significant and dose-dependent increases in tumor volume. Quantitative analysis of the intensity of collagen fibers and their organization in stroma and peri-tumoral microenvironment showed significant differences between irradiated and control group. Blood vessels count of 21-J group outnumbered the other groups. High doses (= 9 J) of LP showed a dose-dependent tumor growth, different collagen fibers characteristics, and eventually blood vessel growth, while a typical LLLT dose (3 J) appeared harmless on melanoma cell activity

High doses of laser phototherapy can increase proliferation in melanoma stromal connective tissue

It is well established that laser phototherapy (LP) is contraindicated directly over cancer cells, due to its bio modulatory effects in cell and blood vessel proliferation. The aim of the present study was to analyze the influence of typical low-level laser therapy (LLLT) and high intensity laser therapy (HILT) and an in-between dose of 9 J on collagen fibers and blood vessels content in melanoma tumors (B16F10) implanted in mice. Melanoma tumor cells were injected in male Balb C mice which were distributed in four groups: control (no irradiated) or irradiated by 3, 9, or 21 J (150; 450, or 1050 J/cm2). LP was performed in daily sessions for 3 days with a InGaAlP—660 nm (mean output: 50 mW, spot size: 2 mm2). Tumor volume was analyzed using (1) picrosirius staining to quantify collagen fibers content and (2) Verhoeff’s method to quantify blood vessels content. Tumor growth outcome measured in the 3-J group was not significantly different from controls. Nine and 21-J groups, presented significant and dose-dependent increases in tumor volume. Quantitative analysis of the intensity of collagen fibers and their organization in stroma and peri-tumoral microenvironment showed significant differences between irradiated and control group. Blood vessels count of 21-J group outnumbered the other groups. High doses (= 9 J) of LP showed a dose-dependent tumor growth, different collagen fibers characteristics, and eventually blood vessel growth, while a typical LLLT dose (3 J) appeared harmless on melanoma cell activity