Enhancement of cellular activity in hyperglycemic mice dermal wounds dressed with chitosan-alginate membranes

The use of specially designed wound dressings could be an important alternative to facilitate the healing process of wounds in the hyperglycemic state. Biocompatible dressings combining chitosan and alginate can speed up wound healing by modulating the inflammatory phase, stimulating fibroblast proliferation, and aiding in remodeling phases. However, this biomaterial has not yet been explored in chronic and acute lesions of diabetic patients. The aim of this study was to evaluate the effect of topical treatment with a chitosan-alginate membrane on acute skin wounds of hyperglycemic mice. Diabetes mellitus was induced by streptozotocin (60 mg · kg-1 · day-1 for 5 days, intraperitoneally) and the cutaneous wound was performed by removing the epidermis using a surgical punch. The results showed that after 10 days of treatment the chitosan and alginate membrane (CAM) group exhibited better organization of collagen fibers. High concentrations of interleukin (IL)-1α, IL-1β, granulocyte colony-stimulating factor (G-CSF), and tumor necrosis factor-alpha (TNF-α) were detected in the first and second days of treatment. G-CSF and TNF-α level decreased after 5 days, as well as the concentrations of TNF-α and IL-10 compared with the control group (CG). In this study, the inflammatory phase of cutaneous lesions of hyperglycemic mice was modulated by the use of CAM, mostly regarding the cytokines IL-1α, IL-1β, TNF-α, G-CSF, and IL-10, resulting in better collagen III deposition. However, further studies are needed to better understand the healing stages associated with CAM use.

Enhancement of cellular activity in hyperglycemic mice dermal wounds dressed with chitosan-alginate membranes.

The use of specially designed wound dressings could be an important alternative to facilitate the healing process of wounds in the hyperglycemic state. Biocompatible dressings combining chitosan and alginate can speed up wound healing by modulating the inflammatory phase, stimulating fibroblast proliferation, and aiding in remodeling phases. However, this biomaterial has not yet been explored in chronic and acute lesions of diabetic patients. The aim of this study was to evaluate the effect of topical treatment with a chitosan-alginate membrane on acute skin wounds of hyperglycemic mice. Diabetes mellitus was induced by streptozotocin (60 mg · kg-1 · day-1 for 5 days, intraperitoneally) and the cutaneous wound was performed by removing the epidermis using a surgical punch. The results showed that after 10 days of treatment the chitosan and alginate membrane (CAM) group exhibited better organization of collagen fibers. High concentrations of interleukin (IL)-1α, IL-1ß, granulocyte colony-stimulating factor (G-CSF), and tumor necrosis factor-alpha (TNF-α) were detected in the first and second days of treatment. G-CSF and TNF-α level decreased after 5 days, as well as the concentrations of TNF-α and IL-10 compared with the control group (CG). In this study, the inflammatory phase of cutaneous lesions of hyperglycemic mice was modulated by the use of CAM, mostly regarding the cytokines IL-1α, IL-1ß, TNF-α, G-CSF, and IL-10, resulting in better collagen III deposition. However, further studies are needed to better understand the healing stages associated with CAM use.

Polypropylene meshes coated with chitosan/polyethylene glycol for the reconstruction of the abdominal wall: an experimental study in rats / Telas de polipropileno revestidas com o filme de quitosana/polietilenoglicol para a reconstrução da parede abdominal: estudo experimental em ratos

The aim of this study was to characterize the tissue reactions triggered by the polypropylene mesh coated with chitosan and polyethylene glycol film, and if it's able to prevent the formation of peritoneal adhesions. Defects in the abdominal wall of rats were induced and polypropylene meshes coated with chitosan/polyethylene glycol (CPEG group, n= 12) and uncoated (PP control group, n= 12) were implanted. On the fourth and forty-fifth postoperative day the formation of adhesion and the tissue reaction to the biomaterial was evaluated through histological and histochemical analysis. The area (P= 0.01) and severity (P= 0.002) of the adhesion was significatively less in the CPEG group. On the fourth day the foreign body reaction was less intense in CPEG group (P= 0.018) and the production of collagen fibers was more intense in this group (P= 0.041). The tissue reactions caused by the biomaterials were similar on the 45th day, with the exception of the high organization of collagen fibers in the CPEG group. The CPEG meshes did not fully prevent the formation of adhesions, but minimized the severity of the process. The foreign body reaction promoted by polypropylene meshes coated with CPEG is less intense than that triggered by uncoated polypropylene meshes.(AU)

O objetivo deste estudo foi caracterizar as reações tissulares desencadeadas pela tela de polipropileno revestida com o filme de quitosana e polietilenoglicol e verificar se ela é capaz de prevenir a formação de aderências peritoneais. Um defeito na parede abdominal dos ratos foi realizado, e as telas de polipropileno revestidas com quitosana/polietilenoglicol (grupo CPEG, n= 12) e sem revestimento (grupo controle PP, n= 12) foram implantadas. No quarto e no 45º dia pós-operatório, avaliou-se a formação de aderências e a reação tecidual ao biomaterial por análise histológica e histoquímica. A área (P= 0,01) e a severidade (P= 0,002) da aderência peritoneal foram significativamente menores no grupo CPEG no 45º dia. No quarto dia, observou-se que a reação do corpo estranho foi menor no grupo CPEG (P= 0,018), e a produção de fibras de colágeno mais intensa (P= 0,041). As reações tissulares causadas pelos biomateriais implantados foram semelhantes no 45º dia, com exceção da melhor organização das fibras colágenas no grupo CPEG. As telas CPEG não impediram completamente a formação de aderências, porém minimizaram a gravidade do processo. A reação de corpo estranho promovida por telas de polipropileno revestidas com CPEG é menos intensa do que a desencadeada por telas de polipropileno não revestidas.(AU)

Skin cancer prevention campaign in childhood: survey based on 3676 children in Brazil.

BACKGROUND AND OBJECTIVES: Primary skin cancer prevention campaigns are essential and more effective among children, not only because of the importance of sun exposure effects during this period, but also because this age is when individuals are developing behaviours. The Brazilian Society of Dermatology - Regional State of Sao Paulo developed and conducted the programme named 'The Sun, Friend of Childhood', a school health education and disease prevention project for children and parents. Our objective was to evaluate the cognitive and behavioural effects of the children and parents before and after an education model-based intervention of sun protection. METHODS: We carried out a study on a school population of Social Service of Industry - Regional State of São Paulo, from the first to the fifth years of the regular course (6-10 years). Our educational project was planned to be based on two children's learning tools (comic magazine and a DVD cartoon). Questionnaires in relation to habits and knowledge in sun exposure were applied to the children (3776) before and (2748) after the intervention. A questionnaire was applied to 3663 parents regarding personal details and habits of their children. RESULTS: According to the McNemar's statistical test, all changes in the children in acquiring new knowledge about good practices for sun exposure were statistically significant. CONCLUSIONS: Educative sun exposure programmes in childhood are a relevant tool to modify the history of life for next generations, to concern the skin cancer and good health practices.

Chronic telogen effluvium and female pattern hair loss are separate and distinct forms of alopecia: a histomorphometric and immunohistochemical analysis.

BACKGROUND: Chronic telogen effluvium (CTE), a poorly understood condition, can be confused with or may be a prodrome to female pattern hair loss (FPHL). The pathogenesis of both is related to follicle cycle shortening and possibly to blood supply changes. AIM: To analyze a number of histomorphometric and immunohistochemical findings through vascular endothelial growth factor (VEGF), Ki-67, and CD31 immunostaining in scalp biopsies of 20 patients with CTE, 17 patients with mild FPHL and 9 controls. METHODS: Ki-67 index and VEGF optical density were analyzed at the follicular outer sheath using ImageJ software. CD31 microvessel density was assessed by a Chalkley grid. RESULTS: Significant follicle miniaturization and higher density of nonanagen follicles were found in FPHL, compared with patients with CTE and controls. Ki-67+ index correlated positively with FPHL histological features. The FPHL group showed the highest VEGF optical density, followed by the CTE and control groups. No differences were found in CD31 microvessel density between the three groups. CONCLUSIONS: Histomorphometric results establish CTE as a distinct disorder, separate from FPHL from its outset. Its pathogenic mechanisms are also distinct. These findings support the proposed mechanism of 'immediate telogen release' for CTE, leading to cycle synchronization. For FPHL, accelerated anagen follicular mitotic rates and, thus, higher Ki-67 and VEGF values, would leave less time for differentiation, resulting in hair miniaturization.

Bartonella henselae survives after the storage period of red blood cell units: is it transmissible by transfusion?

Bartonella henselae is the agent of cat scratch disease and bacillary angiomatosis. Blood donors can be asymptomatic carriers of B. henselae and the risk for transmission by transfusion should be considered. The objective of this study was to demonstrate that B. henselae remains viable in red blood cell (RBC) units at the end of the storage period. Two RBC units were split into two portions. One portion was inoculated with B. henselae and the other was used as a control. All units were stored at 4 degrees C for 35 days. Aliquots were collected on a weekly basis for culture in a dish with chocolate agar, ideal for the cultivation of this agent. Samples were collected on days 1 and 35 and taken for culture in Bact/Alert R blood culture bottles. Aliquots taken simultaneously were fixed in Karnovsky's medium for subsequent electron microscopy evaluation. Samples from infected bags successfully isolated B. henselae by chocolate agar culture, although Bact/Alert R blood culture bottles remained negative. Bartonella spp. structures within erythrocytes were confirmed by electron microscopy. The viability of B. henselae was demonstrated after a storage period of RBC units. These data reinforce the possibility of infection by transfusion of blood units collected from asymptomatic blood donors.

Preparation and characterization of liposomal systems entrapping the boronated compound o-carboranylpropylamine.

Boron neutron capture therapy (BNCT) is based on the nuclear reaction that occurs when the stable isotope, Boron-10, is irradiated with low-energy thermal neutrons to yield ionizing Helium and Lithium ions that are highly damaging and usually lethal to cells. The successful treatment of cancer by BNCT requires the selective concentration of Boron-10 within malignant tumours. Liposomes have been used as therapeutic compound delivery vehicles for in vivo application, including several anticancer agents. The ability of the boron-containing compound, o-carboranylpropylamine chloride, to accumulate within unilamellar liposomes in response to a transmembrane pH gradient is evaluated. Characterization of the systems obtained is performed for conventional and polyethylene glycol (PEG)-modified (stealth) liposomes, in terms of lipid and CPA contents, vesicle size and stability in detergent solutions. Results demonstrate that CPA loading and vesicle stability can be controlled by the experimental procedure. The loading of CPA into liposomes with average diameters of 100 nm is estimated at 13000 molecules per vesicle for the most stable systems. CPA toxicity to normal human peripheral blood lymphocytes and to adherent glioblastoma multiforme SK-MG-1 cells in vitro is observed to decrease as a result of the entrapment of CPA in liposomes.

Baccilary angiomatosis: negative results using normal Balb/c and Balb/c nude mice

Baccilary angiomatosis has recently been described as a disease that can spread systematically and that is potentially fatal. It is caused by Bartonella henselae and B. quintana, and presents as especially pronounced signs and symptoms in patients suffering from acquired immunodeficiency syndrome (AIDS). To clarify the pathogenesis of the disease and to try to define the relationships among baccilary angiomatosis, cat scratch disease and Carrión's bartonellosis, the authors of this study have attempted to develop an experimental model using mice that were immunocompetent as well as those that had their cellular immunity genetically compromised. A know concentration of B. henselae was inoculated intradermally in Balb/c an isogenic mice or an athymic group of the same lineage. Blood samples were taken on days-0, 3, 7, 10, 14, 28, and 60 after inoculation for indirect immunofluorescence antibody testing. On the 21st and 60th day, one animal from each group was sacrificed and a post mortem carried out including histological evaluation of the liver, spleen, lymph nodes, skin and other organs. Hemocultures of the sacrificed animals were collected. All results of serologic response, cultures and histologic examination were negative. The authors discuss the methodology, especially the use of isogenic animals of the same lineage in B. henselae infection, with and without immunodeficiency, and the resources for the negative results of histopathology, serology and cultures.

Use of autologous fibrin glue in dermatologic surgery: application of skin graft and second intention healing.

OBJECTIVE: To evaluate the efficiency of biological sealant, an autologous fibrin glue, in dermatological surgery. DESIGN: Randomized clinical trial. SETTING: The Dermatology Service of Hospital das Clinicas, Universidade de Campinas (UNICAMP), referral center. PATIENTS: 14 patients with malign epithelial cutaneous tumors participated in the evaluation, each having two tumors, generally facial and symmetrical, in order to perform a comparative evaluation on the same individual. PROCEDURES: The glue was prepared beforehand with a sample of autologous blood. Surgical extirpation of the tumor was followed by grafts or second intention healing. OUTCOMES: The efficiency of the sealant was then evaluated in relation to hemostasis, adhesion, surgical time and evolution of the granulation tissue, clinically and histologically. RESULTS: Immediate hemostasis and graft adhesion, with a significant reduction of surgical time, and in the open wounds there was immediate hemostasis and a clinical increase in granulation tissue, but with no histological differences among the groups on the 7th day. CONCLUSION: It is an adjuvant resource in skin cancer surgery.

Characterization of coatings for open-heart surgery tubing with heparin and lipid.

The aim of this study was to compare qualitative and quantitative methods for coating characterization on internal surfaces of polyvinyl chloride (PVC) tubing used in procedures of extracorporeal circulation. The methods of characterization included optical microscopy (OM) after dyeing with toluidine blue, scanning electron microscopy (SEM), atomic force microscopy (AFM) and energy dispersive spectrometry (EDS). OM after sample dyeing was excellent in allowing early detection of any absence or irregularities of coatings among the used methods. SEM was the most effective in observing the structure and thickness either in heparin coatings or in lipid coatings. AFM provided a good evaluation of the surface topography. A conjunction of all methods is recommended for complete characterization. The quantification methods based on colorimetric tests were efficient in determining the concentrations of heparin and lipid on internal surface tubes, the coating stability and the reproducibility of the results.

Insulin resistance in psoriasis

The oral glucose tolerance test (OGTT) and intravenous insulin tolerance test (15-min ITT) were applied to ten patients with psoriasis and to 11 control subjects. No significant differences in mean plasma glucose levels were detected between psoriatic patients and normal individuals. In contrasts, serum insulin levels were significantly higher for the psoriatic patients as compared to the controls at 30, 60 and 120 min during the OGTT (P<0.05). The glucose disappearance rate during the 15-min ITT was lower in patients with psoriasis than in controls (5.1 + or - 0.5 percent min vs 7.5 + or - 0.4 percent/min, P<0.05), demonstrating a state of insulin resistance. Interestingly, the reduction in serum potassium levels during the ITT was also lower in the patients than in the controls (0.6 + or - 0.06 mEq/l vs 1.06 + or - 0.07 mEq/l,P<0.05), suggesting that the insulin resistance observed in psoriasis is not only related to glucose metabolism, but also to another important action of insulin, namely extrarenal potassium homeostasis

Piodermite vegetante: estudo clínico e terapêutico / Pyodermitis vegetans: clinical and therapeutic study

Os autores apresentam um caso de piodermite vegetante, ou piodermite semelhante à blastomicose, dermatose rara e de difícil diagnóstico clínico e laboratorial em nosso meio.Manifesta-se com morfologia exuberante e comum a várias dermatoses infecciosas. Trata-se de provável resposta tecidual proliferativa e alteraçäo imunológica individuais à presença dos agentes infecciosos encontados. A resposta terapêutica à corticoterapia foi relevante, pórem introduzida somente após exaustiva procura dos prováveis diagnósticos diferenciais

Estrongiloidíase: caso fatal por peritonite secundária à perfuraçäo intestinal / Strongyloidiasis: fatal case due to peritonitis secondary to intestinal perforation

Descreve-se um caso de estrongiloidíase complicado por peritonite secundária a perfuraçäo intestinal, com evoluçäo fatal, na vigência de terapêutica imunossupressora (corticoterapia)