Marco Andrey Cipriani Frade | Universidade de São Paulo (original) (raw)
Papers by Marco Andrey Cipriani Frade
Biochemical and Biophysical Research Communications, 490 (4), 1154-1161, 2017.
Diabetes can cause serious health complications, which can affect every organ of the body, includ... more Diabetes can cause serious health complications, which can affect every organ of the body, including the skin. The molecular etiology has not yet been clarified for all diabetic skin conditions. Thus, this study aimed to investigate the changes of diabetes in skin compared to non-diabetic skin in rats. Fifteen days after establishing the diabetic status, skin samples from the dorsum-cervical region were harvested for subsequent analysis of alterations caused by diabetes. Our results demonstrate that diabetes stimulated higher inflammation and oxidative stress in skin, but antioxidant defense levels were lower compared to the non-diabetic group (p < 0.05). This could have been related to a decreased number of blood vessels and low expression of VEGF, eNOS and TGF-b1. Finally, insulin signaling proteins IRS, Akt, Shc and ERK showed a low expression in the diabetic group. Thus, our study shows that the pathology of diabetes induced immunohistopathological and biochemical skin changes compared to non-diabetic skin in rats.
Revista Brasileira de Plantas Medicinais, 2013
Recebido para publicação em 03/05/2011 Aceito para publicação em 12/07/2013 RESUMO: Este trabalho... more Recebido para publicação em 03/05/2011 Aceito para publicação em 12/07/2013 RESUMO: Este trabalho avaliou a atividade antimicrobiana in vitro do óleo-resina da Copaifera langsdorffii, o qual vem sendo utilizado há muitos anos na medicina tradicional popular, principalmente devido às suas propriedades antiinflamatórias, antibacterianas, cicatrizante entre outras. O óleo-resina foi testado em bactérias Gram-positivas (Staphylococcus aureus, Streptococcus pyogenes, Enterococcus faecalis) e Gram-negativas (Pseudomonas aeruginosa e Escherichia coli) relacionadas com infecções de úlceras cutâneas. A atividade antimicrobiana foi determinada pelos testes da Concentração Inibitória Mínima (CIM) e Concentração Bactericida Mínima (CBM). O óleo-resina apresentou atividade antimicrobiana in vitro apenas para as bactérias Gram-positivas, com valores de CIM de 200 μg/mL, 400 μg/mL e 1100 μg/mL para S. aureus, S. pyogenes e E. faecalis, respectivamente. Os valores de CBM foram os mesmos que os valores de MIC para S. aureus e S. pyogenes. O valor de CBM para o microrganismo E. faecalis foi de 1200 μg/mL. Considerando que a presença de infecção significativamente impede o processo normal de cicatrização de úlceras cutâneas, acreditamos que o óleo-resina de copaíba, utilizado como componente de formulações tópicas, poderia ser um adjunto importante no tratamento de úlceras cutâneas infectadas, principalmente nos casos de infecção por microrganismos Gram-positivos.
Brazilian journal of medical and biological research = Revista brasileira de pesquisas médicas e biológicas / Sociedade Brasileira de Biofísica ... [et al.], 2011
The aim of the present study was to compare healing obtained with biomembranes with the natural h... more The aim of the present study was to compare healing obtained with biomembranes with the natural healing process (sham) using biochemical and immunohistological assays. C57BL/6 mice were divided into 4 groups of 15 mice each and received different subcutaneous implants: natural latex biomembrane (NLB), denatured latex (DL), expanded polytetrafluorethylene (ePTFE), or sham. On the 2nd, 7th, and 14th days post-treatment, 5 mice per group were sacrificed and biopsied for the following measurements: oxidative stress based on malondialdehyde (MDA), myeloperoxidase (MPO) and hydrogen peroxide by the method of ferrous oxidation-xylenol orange (FOX), as well as glutathione and total proteins; histological evaluation to enumerate inflammatory cells, fibroblasts, blood vessels, and collagen, and immunohistochemical staining for inducible nitric oxide synthase, interleukin-1β, vascular endothelial growth factor (VEGF), and transforming growth factor-β1 (TGF-β1). On day 2 post-treatment, NLB sti...
Journal of neuroscience methods, Jan 15, 2009
To propose an electronic method for sensitivity evaluation in leprosy and to compare it to the Se... more To propose an electronic method for sensitivity evaluation in leprosy and to compare it to the Semmes-Weinstein monofilaments. Thirty patients attending the Dermatology outpatient clinic of HCFMRP-USP were consecutively evaluated by both the electronic aesthesiometer and Semmes-Weinstein monofilaments on hand and foot test points. The intraclass correlation coefficient (ICC) was calculated to determine the variability of the electronic measures and the Kappa coefficient was calculated to determine the agreement between methods according to their categories (altered and non-altered tactile sensitivity). The ICC was approximately 1, demonstrating repeatability. The Kappa coefficient showed more than 75 and 63% agreement on the hand and foot points, respectively. The mean agreement between the 2 methods for the 7 points of the right and left hand was 77.14 and 75.71%, respectively. The mean agreement for all 10 points was 74.33 and 63.66% on the right and left foot, respectively. In ca...
The international journal of lower extremity wounds, Jan 25, 2014
Leprosy is a chronically evolving granulomatous disease caused by the bacillus Mycobacterium lepr... more Leprosy is a chronically evolving granulomatous disease caused by the bacillus Mycobacterium leprae, which exhibits tropism for peripheral and motor nerves and slow-growing inflammation that affects the peripheral nervous system, especially the sensory fibers. The aim of this study was to observe the relationship between peak pressure and abnormal sensitivity for the formation of plantar ulcers in patients with multibacillary (MB) and paucibacillary (PB) leprosy. A total of 51 individuals with leprosy were evaluated and classified as either MB or PB and then submitted to the Semmes-Weinstein sensitivity test; 20 normal individuals were examined as a control group and took a baropodometric test. The pressure peaks and sensitivity alterations were noted and compared within groups. Leprosy patients exhibited a greater loss of sensitivity at the heel area that might compromise gait. During dynamic analysis, the MB group with altered sensitivity for right and left feet and PB (left feet)...
BACKGROUND: The vegetal biomembrane has been used to treat cutaneous ulcers. OBJECTIVES: To asses... more BACKGROUND: The vegetal biomembrane has been used to treat cutaneous ulcers. OBJECTIVES: To assess the role of the vegetal biomembrane on the chronic venous ulcers treatment compared to treatment with collagenase cream. METHODS: Fourteen patients were selected to be treated with vegetal biomembrane and 7 with Fibrase ® (CON-TROL), followed clinically and photographically by the Wound Healing Index by ImageJ during 120 days and biopsied on the 1 st and 30 th days for histological examination. RESULTS: The vegetal biomembrane was better in promoting healing of the ulcers, especially on the inflammatory phase, confirmed by abundant exudation and wound debridement than the CONTROL group, on the 30 th day. There was a greater tendency to angiogenesis followed by re-epithelialization with highest wound healing index on the 90 th and 120 th days. CONCLUSION: A combined analysis of clinical and histopathological findings suggests that the vegetal biomembrane acted as a factor inducing wound healing, especially on the inflammatory phase, confirmed by abundant exudation of the lesions promoting the transformation of the microenvironment of the chronic venous ulcers, and also stimulating angiogenesis and subsequent re-epithelialization.
European Journal of Pharmaceutical Sciences, 2015
Appropriate therapeutics for wound treatments can be achieved by studying the pathophysiology of ... more Appropriate therapeutics for wound treatments can be achieved by studying the pathophysiology of tissue repair. Here we develop formulations of lamellar gel phase (LGP) emulsions containing marigold (Calendula officinalis) oil, evaluating their stability and activity on experimental wound healing in rats.
Journal of Neurosciences in Rural Practice, 2014
2008 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2008
This paper presents color image processing methods for the analysis of dermatological images in t... more This paper presents color image processing methods for the analysis of dermatological images in the context of a content-based image retrieval (CBIR) system. Tests were conducted on the classification of tissue components in skin lesions, in terms of necrotic tissue, fibrin, granulation, and mixed composition. The images were classified based on color components by an expert dermatologist following a black-yellow-red model. Indexing and retrieval of images were performed based on texture information obtained from the red, green, blue, hue, and saturation components of the color images. The performance of the CBIR system was measured in terms of precision and recall. Initial results demonstrate the potential of the proposed methods with the best precision result of 70% obtained for the characterization of mixed tissue composition.
IEEE Journal of Biomedical and Health Informatics, 2013
We present color image processing methods for the analysis of images of dermatological lesions. T... more We present color image processing methods for the analysis of images of dermatological lesions. The focus of the present work is on the application of feature extraction and selection methods for classification and analysis of the tissue composition of skin lesions or ulcers, in terms of granulation (red), fibrin (yellow), necrotic (black), callous (white), and mixed tissue composition. The images were analyzed and classified by an expert dermatologist into the classes mentioned above. Indexing of the images was performed based on statistical texture features derived from cooccurrence matrices of the RGB (Red, Green, and Blue), HSI (Hue, Saturation, and Intensity), L*a*b*, and L*u*v* color components. Feature selection methods were applied using the Wrapper algorithm with different classifiers. The performance of classification was measured in terms of the percentage of correctly classified images and the area under the receiver operating characteristic curve, with values of up to 73.8% and 0.82, respectively.
International Journal of Dermatology, 2001
Frade, MAC, Valverde, RV, De Assis, RVC, Coutinho-Netto, J. and Foss, NT (2001), Chronic phlebopa... more Frade, MAC, Valverde, RV, De Assis, RVC, Coutinho-Netto, J. and Foss, NT (2001), Chronic phlebopathic cutaneous ulcer: a therapeutic proposal. International Journal of Dermatology, 40: 238240. doi: 10.1046/j. 1365-4362.2001. 00977-2. x
Journal of Inflammation Research, 2014
Nuclear factor kappa B (NFκB) transcription factors play a central role in controlling the expres... more Nuclear factor kappa B (NFκB) transcription factors play a central role in controlling the expression of genes involved in inflammatory reactions, proliferation, and survival of human cells. However, the in situ evaluation of NFκB activity in leprosy has not been completed previously. The aim of this study was to determine whether NFκB activity correlates with susceptibility or resistance to Mycobacterium leprae infection in biopsies from skin lesions of 38 patients with the clinical and laboratory diagnosis of leprosy. The NFκB activation profile was evaluated in biopsies from skin lesions of 38 patients with the clinical and laboratory diagnosis of leprosy. NFκB activation was evaluated and quantified by Southwestern histochemistry, and its activation index (range, 0-4) was calculated according to the percentage of nuclear positivity by the histochemistry. Activation index &amp;amp;amp;amp;amp;gt;1 was considered representative of activation of NFκB. Fifteen patients (39.5%) demonstrated activated NFκB. Multibacillary leprosy was associated with activated NFκB (54.5%, P=0.028). Borderline leprosy was most strongly associated with NFκB activation (80%), with an odds ratio of 32.7 (P=0.016). These clinical forms are characterized by increased susceptibility to M. leprae and by immunological instability. Activation of NFκB was absent in the granulomas in tuberculoid leprosy, which represents an effective inflammatory reaction pattern against M. leprae. These results indicate that NFκB activation could favor susceptibility and immunological instability to M. leprae infection, potentially by the stimulation of phagocytosis and the regulation of apoptotic mechanisms of infected cells, leading to the proliferation of this intracellular bacillus. Further studies are needed to evaluate if inhibition of NFκB activation in multibacillary leprosy could favor resistance and an effective granulomatous immune response.
Anais brasileiros de dermatologia
The skin requires adequate levels of nutrients to function properly. To analyze skin trophism in ... more The skin requires adequate levels of nutrients to function properly. To analyze skin trophism in well-nourished and undernourished rats using two models of malnutrition. In the marasmus model, 60 Wistar rats were kept on a controlled diet, 30 being randomly selected to receive half the established diet for 60 days. In the gelatin model, 60 rats were used, 30 of which received a diet consisting of poor quality protein (gelatin) for 30 days. The nutritional status of the animals was evaluated according to body mass index, clinical signs and serum albumin measurement. After the period of malnutrition, histology was performed on the animals' skin to analyze the thickness of the dermis and epidermis using the Leica Application Suite software. Collagen was analyzed on slides stained with Gömöri trichrome using the ImageJ software program. The body mass index of the malnourished animals in the marasmus and gelatin groups was significantly lower than that of the well-nourished animals i...
Anais brasileiros de dermatologia
The natural biomembrane of latex extracted from Hevea brasiliensis has been used as a dressing fo... more The natural biomembrane of latex extracted from Hevea brasiliensis has been used as a dressing for skin ulcers. To evaluate how safe the natural biomembrane is in relation to hypersensitivity to latex when used as a dressing. We selected patients with skin ulcers, forming the following groups: control - low occupational exposure to latex (n = 17); latex-exposed control - high occupational exposure (n = 14); ulcerated, using the natural biomembrane (n = 13); ulcerated control, not using the natural biomembrane (n = 14); and new cases (n = 9), assessed before and after 3 months of using the natural biomembrane. All patients underwent clinical and epidemiological evaluation for latex hypersensitivity and specific IgE (UniCap(®)), and the control and latex-exposed control groups underwent the patch test. Hypersensitivity was positive in 64.7% of the patients in the control group, 71.4% of the patients in the latex-exposed control group, 61.5% of the ulcerated using the natural biomembra...
Biochemical and Biophysical Research Communications, 490 (4), 1154-1161, 2017.
Diabetes can cause serious health complications, which can affect every organ of the body, includ... more Diabetes can cause serious health complications, which can affect every organ of the body, including the skin. The molecular etiology has not yet been clarified for all diabetic skin conditions. Thus, this study aimed to investigate the changes of diabetes in skin compared to non-diabetic skin in rats. Fifteen days after establishing the diabetic status, skin samples from the dorsum-cervical region were harvested for subsequent analysis of alterations caused by diabetes. Our results demonstrate that diabetes stimulated higher inflammation and oxidative stress in skin, but antioxidant defense levels were lower compared to the non-diabetic group (p < 0.05). This could have been related to a decreased number of blood vessels and low expression of VEGF, eNOS and TGF-b1. Finally, insulin signaling proteins IRS, Akt, Shc and ERK showed a low expression in the diabetic group. Thus, our study shows that the pathology of diabetes induced immunohistopathological and biochemical skin changes compared to non-diabetic skin in rats.
Revista Brasileira de Plantas Medicinais, 2013
Recebido para publicação em 03/05/2011 Aceito para publicação em 12/07/2013 RESUMO: Este trabalho... more Recebido para publicação em 03/05/2011 Aceito para publicação em 12/07/2013 RESUMO: Este trabalho avaliou a atividade antimicrobiana in vitro do óleo-resina da Copaifera langsdorffii, o qual vem sendo utilizado há muitos anos na medicina tradicional popular, principalmente devido às suas propriedades antiinflamatórias, antibacterianas, cicatrizante entre outras. O óleo-resina foi testado em bactérias Gram-positivas (Staphylococcus aureus, Streptococcus pyogenes, Enterococcus faecalis) e Gram-negativas (Pseudomonas aeruginosa e Escherichia coli) relacionadas com infecções de úlceras cutâneas. A atividade antimicrobiana foi determinada pelos testes da Concentração Inibitória Mínima (CIM) e Concentração Bactericida Mínima (CBM). O óleo-resina apresentou atividade antimicrobiana in vitro apenas para as bactérias Gram-positivas, com valores de CIM de 200 μg/mL, 400 μg/mL e 1100 μg/mL para S. aureus, S. pyogenes e E. faecalis, respectivamente. Os valores de CBM foram os mesmos que os valores de MIC para S. aureus e S. pyogenes. O valor de CBM para o microrganismo E. faecalis foi de 1200 μg/mL. Considerando que a presença de infecção significativamente impede o processo normal de cicatrização de úlceras cutâneas, acreditamos que o óleo-resina de copaíba, utilizado como componente de formulações tópicas, poderia ser um adjunto importante no tratamento de úlceras cutâneas infectadas, principalmente nos casos de infecção por microrganismos Gram-positivos.
Brazilian journal of medical and biological research = Revista brasileira de pesquisas médicas e biológicas / Sociedade Brasileira de Biofísica ... [et al.], 2011
The aim of the present study was to compare healing obtained with biomembranes with the natural h... more The aim of the present study was to compare healing obtained with biomembranes with the natural healing process (sham) using biochemical and immunohistological assays. C57BL/6 mice were divided into 4 groups of 15 mice each and received different subcutaneous implants: natural latex biomembrane (NLB), denatured latex (DL), expanded polytetrafluorethylene (ePTFE), or sham. On the 2nd, 7th, and 14th days post-treatment, 5 mice per group were sacrificed and biopsied for the following measurements: oxidative stress based on malondialdehyde (MDA), myeloperoxidase (MPO) and hydrogen peroxide by the method of ferrous oxidation-xylenol orange (FOX), as well as glutathione and total proteins; histological evaluation to enumerate inflammatory cells, fibroblasts, blood vessels, and collagen, and immunohistochemical staining for inducible nitric oxide synthase, interleukin-1β, vascular endothelial growth factor (VEGF), and transforming growth factor-β1 (TGF-β1). On day 2 post-treatment, NLB sti...
Journal of neuroscience methods, Jan 15, 2009
To propose an electronic method for sensitivity evaluation in leprosy and to compare it to the Se... more To propose an electronic method for sensitivity evaluation in leprosy and to compare it to the Semmes-Weinstein monofilaments. Thirty patients attending the Dermatology outpatient clinic of HCFMRP-USP were consecutively evaluated by both the electronic aesthesiometer and Semmes-Weinstein monofilaments on hand and foot test points. The intraclass correlation coefficient (ICC) was calculated to determine the variability of the electronic measures and the Kappa coefficient was calculated to determine the agreement between methods according to their categories (altered and non-altered tactile sensitivity). The ICC was approximately 1, demonstrating repeatability. The Kappa coefficient showed more than 75 and 63% agreement on the hand and foot points, respectively. The mean agreement between the 2 methods for the 7 points of the right and left hand was 77.14 and 75.71%, respectively. The mean agreement for all 10 points was 74.33 and 63.66% on the right and left foot, respectively. In ca...
The international journal of lower extremity wounds, Jan 25, 2014
Leprosy is a chronically evolving granulomatous disease caused by the bacillus Mycobacterium lepr... more Leprosy is a chronically evolving granulomatous disease caused by the bacillus Mycobacterium leprae, which exhibits tropism for peripheral and motor nerves and slow-growing inflammation that affects the peripheral nervous system, especially the sensory fibers. The aim of this study was to observe the relationship between peak pressure and abnormal sensitivity for the formation of plantar ulcers in patients with multibacillary (MB) and paucibacillary (PB) leprosy. A total of 51 individuals with leprosy were evaluated and classified as either MB or PB and then submitted to the Semmes-Weinstein sensitivity test; 20 normal individuals were examined as a control group and took a baropodometric test. The pressure peaks and sensitivity alterations were noted and compared within groups. Leprosy patients exhibited a greater loss of sensitivity at the heel area that might compromise gait. During dynamic analysis, the MB group with altered sensitivity for right and left feet and PB (left feet)...
BACKGROUND: The vegetal biomembrane has been used to treat cutaneous ulcers. OBJECTIVES: To asses... more BACKGROUND: The vegetal biomembrane has been used to treat cutaneous ulcers. OBJECTIVES: To assess the role of the vegetal biomembrane on the chronic venous ulcers treatment compared to treatment with collagenase cream. METHODS: Fourteen patients were selected to be treated with vegetal biomembrane and 7 with Fibrase ® (CON-TROL), followed clinically and photographically by the Wound Healing Index by ImageJ during 120 days and biopsied on the 1 st and 30 th days for histological examination. RESULTS: The vegetal biomembrane was better in promoting healing of the ulcers, especially on the inflammatory phase, confirmed by abundant exudation and wound debridement than the CONTROL group, on the 30 th day. There was a greater tendency to angiogenesis followed by re-epithelialization with highest wound healing index on the 90 th and 120 th days. CONCLUSION: A combined analysis of clinical and histopathological findings suggests that the vegetal biomembrane acted as a factor inducing wound healing, especially on the inflammatory phase, confirmed by abundant exudation of the lesions promoting the transformation of the microenvironment of the chronic venous ulcers, and also stimulating angiogenesis and subsequent re-epithelialization.
European Journal of Pharmaceutical Sciences, 2015
Appropriate therapeutics for wound treatments can be achieved by studying the pathophysiology of ... more Appropriate therapeutics for wound treatments can be achieved by studying the pathophysiology of tissue repair. Here we develop formulations of lamellar gel phase (LGP) emulsions containing marigold (Calendula officinalis) oil, evaluating their stability and activity on experimental wound healing in rats.
Journal of Neurosciences in Rural Practice, 2014
2008 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2008
This paper presents color image processing methods for the analysis of dermatological images in t... more This paper presents color image processing methods for the analysis of dermatological images in the context of a content-based image retrieval (CBIR) system. Tests were conducted on the classification of tissue components in skin lesions, in terms of necrotic tissue, fibrin, granulation, and mixed composition. The images were classified based on color components by an expert dermatologist following a black-yellow-red model. Indexing and retrieval of images were performed based on texture information obtained from the red, green, blue, hue, and saturation components of the color images. The performance of the CBIR system was measured in terms of precision and recall. Initial results demonstrate the potential of the proposed methods with the best precision result of 70% obtained for the characterization of mixed tissue composition.
IEEE Journal of Biomedical and Health Informatics, 2013
We present color image processing methods for the analysis of images of dermatological lesions. T... more We present color image processing methods for the analysis of images of dermatological lesions. The focus of the present work is on the application of feature extraction and selection methods for classification and analysis of the tissue composition of skin lesions or ulcers, in terms of granulation (red), fibrin (yellow), necrotic (black), callous (white), and mixed tissue composition. The images were analyzed and classified by an expert dermatologist into the classes mentioned above. Indexing of the images was performed based on statistical texture features derived from cooccurrence matrices of the RGB (Red, Green, and Blue), HSI (Hue, Saturation, and Intensity), L*a*b*, and L*u*v* color components. Feature selection methods were applied using the Wrapper algorithm with different classifiers. The performance of classification was measured in terms of the percentage of correctly classified images and the area under the receiver operating characteristic curve, with values of up to 73.8% and 0.82, respectively.
International Journal of Dermatology, 2001
Frade, MAC, Valverde, RV, De Assis, RVC, Coutinho-Netto, J. and Foss, NT (2001), Chronic phlebopa... more Frade, MAC, Valverde, RV, De Assis, RVC, Coutinho-Netto, J. and Foss, NT (2001), Chronic phlebopathic cutaneous ulcer: a therapeutic proposal. International Journal of Dermatology, 40: 238240. doi: 10.1046/j. 1365-4362.2001. 00977-2. x
Journal of Inflammation Research, 2014
Nuclear factor kappa B (NFκB) transcription factors play a central role in controlling the expres... more Nuclear factor kappa B (NFκB) transcription factors play a central role in controlling the expression of genes involved in inflammatory reactions, proliferation, and survival of human cells. However, the in situ evaluation of NFκB activity in leprosy has not been completed previously. The aim of this study was to determine whether NFκB activity correlates with susceptibility or resistance to Mycobacterium leprae infection in biopsies from skin lesions of 38 patients with the clinical and laboratory diagnosis of leprosy. The NFκB activation profile was evaluated in biopsies from skin lesions of 38 patients with the clinical and laboratory diagnosis of leprosy. NFκB activation was evaluated and quantified by Southwestern histochemistry, and its activation index (range, 0-4) was calculated according to the percentage of nuclear positivity by the histochemistry. Activation index &amp;amp;amp;amp;amp;gt;1 was considered representative of activation of NFκB. Fifteen patients (39.5%) demonstrated activated NFκB. Multibacillary leprosy was associated with activated NFκB (54.5%, P=0.028). Borderline leprosy was most strongly associated with NFκB activation (80%), with an odds ratio of 32.7 (P=0.016). These clinical forms are characterized by increased susceptibility to M. leprae and by immunological instability. Activation of NFκB was absent in the granulomas in tuberculoid leprosy, which represents an effective inflammatory reaction pattern against M. leprae. These results indicate that NFκB activation could favor susceptibility and immunological instability to M. leprae infection, potentially by the stimulation of phagocytosis and the regulation of apoptotic mechanisms of infected cells, leading to the proliferation of this intracellular bacillus. Further studies are needed to evaluate if inhibition of NFκB activation in multibacillary leprosy could favor resistance and an effective granulomatous immune response.
Anais brasileiros de dermatologia
The skin requires adequate levels of nutrients to function properly. To analyze skin trophism in ... more The skin requires adequate levels of nutrients to function properly. To analyze skin trophism in well-nourished and undernourished rats using two models of malnutrition. In the marasmus model, 60 Wistar rats were kept on a controlled diet, 30 being randomly selected to receive half the established diet for 60 days. In the gelatin model, 60 rats were used, 30 of which received a diet consisting of poor quality protein (gelatin) for 30 days. The nutritional status of the animals was evaluated according to body mass index, clinical signs and serum albumin measurement. After the period of malnutrition, histology was performed on the animals' skin to analyze the thickness of the dermis and epidermis using the Leica Application Suite software. Collagen was analyzed on slides stained with Gömöri trichrome using the ImageJ software program. The body mass index of the malnourished animals in the marasmus and gelatin groups was significantly lower than that of the well-nourished animals i...
Anais brasileiros de dermatologia
The natural biomembrane of latex extracted from Hevea brasiliensis has been used as a dressing fo... more The natural biomembrane of latex extracted from Hevea brasiliensis has been used as a dressing for skin ulcers. To evaluate how safe the natural biomembrane is in relation to hypersensitivity to latex when used as a dressing. We selected patients with skin ulcers, forming the following groups: control - low occupational exposure to latex (n = 17); latex-exposed control - high occupational exposure (n = 14); ulcerated, using the natural biomembrane (n = 13); ulcerated control, not using the natural biomembrane (n = 14); and new cases (n = 9), assessed before and after 3 months of using the natural biomembrane. All patients underwent clinical and epidemiological evaluation for latex hypersensitivity and specific IgE (UniCap(®)), and the control and latex-exposed control groups underwent the patch test. Hypersensitivity was positive in 64.7% of the patients in the control group, 71.4% of the patients in the latex-exposed control group, 61.5% of the ulcerated using the natural biomembra...