Abstract The immobilization of the enzyme tyrosinase (Tyr) in lipid matrices can be explored to produce biosensors for detecting polyphenols, which is relevant for the food industry. Herein, we shall demonstrate the importance of the lipid composition to immobilize the enzyme tyrosinase in Langmuir-Blodgett (LB) films. Tyr could be incorporated into Langmuir monolayers of arachidic acid (AA), 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dipalmitoyl-sn-glycero-3-phospho-(1’-rac-glycerol) (sodium salt) (DPPG), having as the main effect an expansion in the monolayers. Results from polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS) pointed to electrostatic interactions between the charged residues of Try and the lipid headgroups, in addition to changes in the order of lipid chains. The interaction between Tyr and DPPC in Langmuir monolayers can be correlated with the superior performance of DPPC/Tyr LB films used as biosensors to detect catechol by cyclic voltammetry. The molecular-level interactions assessed via PM-IRRAS are therefore believed to drive an immobilization process for Tyr in the lipid LB matrix and may serve as a general criterion to identify matrices that preserve enzyme activity.

Abstract This short review gives a concise overview of the impact of deposition methods on the supramolecular arrangement of metallic phthalocyanine films and their applications. Primarily, an introduction about the possible phthalocyanine molecular structures and derivatives obtained from modification on the phthalocyanine rings was presented. The possibility of perfecting/improving the supramolecular arrangement of metallic phthalocyanine (MPcs) films by using different deposition techniques such as Langmuir-Blodgett (LB), Langmuir-Schaefer (LS), Layer-by-Layer (LbL), physical vapor deposition (PVD) and electrodeposition was discussed in further details. Herein, we highlighted some techniques used on the characterization of supramolecular arrangement (morphology, optical properties, and molecular organization), including the impact on sensing applications. The main scope of this short review is focused on the advances made in this research field in the last five years.

RESUMO Introdução: Angiossarcomas são patologias raras, e o aparecimento deles no intestino delgado é extremamente incomum. Relato de caso: Paciente do sexo feminino apresentando vômitos, cólica, distensão abdominal e irritação peritoneal. Foram realizadas laparotomia exploratória e enterectomia, evidenciando-se neoplasia vascular ao anatomopatológico e marcadores CD31, p53 e antígeno de proliferação celular Ki-67 à imuno-histoquímica. A paciente evoluiu com sarcomatose difusa e faleceu dois meses após o início dos sintomas. Conclusão: Demonstra-se a dificuldade em diagnosticar precocemente essa patologia devido à sua clínica inespecífica. A agressividade da doença, seus fatores predisponentes indeterminados e a controvérsia referente ao tratamento adequado suscitam seu péssimo prognóstico.

ABSTRACT Introduction: Angiosarcomas are rare pathologies, and their appearance in the small intestine is extremely unusual. Case report: Female patient presenting vomiting, colic, abdominal distension and peritoneal irritation. An exploratory laparotomy and an enterectomy were performed. Histopathology revealed vascular neoplasm; immunohistochemistry, markers CD31, p53 and cell proliferation antigen Ki-67. The patient developed diffuse sarcomatosis and died two months after the onset of symptoms. Conclusion: This case demonstrates the difficulty in early diagnosing this pathology, due to its nonspecific clinical presentation. The disease aggressiveness, its unestablished predisposing factors and the controversy around the adequate treatment engender the poor prognosis.