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1.
GE Port J Gastroenterol ; 31(3): 203-208, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38836124

RESUMO

Introduction: The association of hepatitis delta virus (HDV) infection with positive autoantibodies and autoimmune features has been known for decades. However, to date, very few cases of clinical autoimmune hepatitis (AIH) have been reported in association with HDV infection, most of them being in the context of treatment with peginterferon. Case Report: This case refers to a 46-year-old woman born in Guinea-Bissau who moved to Portugal in 2018 to investigate complaints of diffuse abdominal discomfort and nausea. Her initial work-up, including laboratory and liver histology, was consistent with type 1 AIH. She had HBe antigen-negative chronic hepatitis B virus infection with negative DNA and also a positive total anti-HDV antibody, with negative IgM and undetectable RNA. Therefore, after initiating prophylactic tenofovir difumarate, she was started on prednisolone followed by azathioprine, which was later stopped due to presumed hepatotoxicity. Repeated histology showed signs of viral superinfection, and she was treated with acyclovir due to a positive herpes simplex IgM, with HDV RNA remaining negative. A third flare in transaminases prompted the introduction of mycophenolate mofetil (MMF) after a thorough exclusion of additional causes of liver disease. About 6 months later, during another bout of hepatitis, HDV RNA was finally positive and classified as genotype 5. MMF was stopped, and, considering a contraindication to interferon, the patient was offered therapy with bulevirtide, which she refused for personal reasons as she is currently living in her home country. Discussion: This is a challenging case of autoimmune or "autoimmune-like" hepatitis, probably induced by chronic HDV infection. High suspicion of HDV was essential because, had the case been interpreted as refractory AIH, with escalation of immunosuppression, a more severe course of the viral infection might have ensued. Recently, HDV suppression with bulevirtide was shown to reverse autoimmune liver disease. We hypothesize that the same could have happened to our patient, had she accepted this treatment.


Introdução: A associação da infeção pelo vírus da hepatite delta (VHD) com a presença de autoanticorpos e outros aspetos de autoimunidade é conhecida desde há várias décadas. Contudo, até à data, muito poucos casos de hepatite autoimune (HAI) clínica foram reportados em relação com a infeção VHD, sendo a maioria destes no contexto de terapêutica com interferão peguilado. Caso clínico: O caso refere-se a uma mulher de 46 anos natural da Guiné-Bissau, que se mudou para Portugal em 2018 para investigação de queixas de desconforto abdominal difuso e náuseas. A avaliação laboratorial inicial e a histologia hepática foram compatíveis com HAI tipo 1. A doente apresentava também infeção crónica a VHB (vírus da hepatite B) antigénio HBe negativa, com DNA negativo, e anti-VHD (vírus da hepatite delta) total positivo, com IgM negativo e RNA indetetável. Assim, após início de tenofovir difumarato profilático, foi iniciada terapêutica com prednisolona seguida de azatioprina, que posteriormente se interrompeu por presumível hepatotoxicidade. Uma segunda biópsia mostrou aspetos de superinfeção viral e como tal a doente foi tratada com aciclovir, tendo em conta IgM positivo para Herpes Simplex, mantendo-se o RNA VHD negativo. Um terceiro flare de transaminases motivou o início de micofenolato de mofetil, após extensa investigação e exclusão de outras causas de doença hepática. Cerca de 6 meses mais tarde, durante novo episódio de hepatite, o RNA VHD revelou-se finalmente positivo e este foi classificado como genotipo 5. O MMF foi suspenso e, considerando a contra-indicação para interferão, foi proposto à doente tratamento com bulevirtide, que esta recusou, alegando motivos pessoais, visto estar atualmente a residir no seu país de origem. Discussão: Este é um caso desafiante de hepatite autoimune, ou autoimune-like, provavelmente induzida pela infeção crónica pelo VHD. Um elevado índice de suspeição para VHD foi essencial porque, se o caso tivesse sido interpretado como HAI refratária, com incremento de imunossupressão, poderia ter-se verificado um agravamento da hepatite viral. Recentemente, foi reportado que a supressão do VHD pelo bulevirtide pode reverter a doença hepática autoimune. Questionamo-nos se o mesmo poderia ter sucedido com a nossa doente, caso esta tivesse aceite este tratamento.

2.
GE Port J Gastroenterol ; 26(3): 155-162, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31192283

RESUMO

BACKGROUND AND AIMS: Vitamin D deficiency is more common in inflammatory bowel disease (IBD) patients than in the general population. However, there are conflicting data about predictive factors of vitamin D deficiency and its potential association with disease activity. The aims of this study were to determine the prevalence and predictive factors of vitamin D deficiency and to evaluate a possible association with disease activity. METHODS: A prospective observational study was conducted, including patients with IBD from January to July 2016. The Endocrine Society guidelines were considered for defining levels of serum 25-hydroxyvitamin D (25-OH-D) as follows: deficient (< 20 ng/mL, < 10 ng/mL being severe deficiency), insufficient (21-29 ng/mL), and adequate (> 30 ng/mL). RESULTS: A total of 152 patients (52% men; 47.2 ± 17.3 years) were included, of whom 70% had Crohn's disease (CD). Thirty-seven percent of patients were on immunosuppressors and 17% were on biologics. The majority were outpatients (88.2%). Mean 25-OH-D levels were 17.1 ± 8 ng/mL (CD: 16.7 ± 8 ng/mL vs. ulcerative colitis: 17.6 ± 7 ng/mL, p = 0.1). Inadequate levels were present in 90.8% of patients (deficiency: 68.4%; insufficiency: 22.4%). A significant negative correlation between 25-OH-D levels and age (r = -0.2, p = 0.04), C-reactive protein (CRP) levels (r = -0.22, p = 0.004), and Harvey-Bradshaw index (HBi) (r = -0.32, p = 0.001) was found. Patients with severe deficiency showed a higher CRP (0.6 vs. 1.4 mg/dL, p = 0.03), erythrocyte sedimentation rate (ESR) (22 vs. 31 mm/h, p = 0.03), and HBi (2 vs. 5, p < 0.001) and lower hemoglobin (13.6 vs. 12.7 g/dL, p = 0.02). There was no association between vitamin D deficiency and gender, type, extent, and duration of disease, surgery, and other measures of disease activity, such as ESR, hemoglobin (these 2 items except for severe deficiency), fecal calprotectin, or Truelove and Witts classification. CONCLUSIONS: There is a high prevalence of inadequate levels of vitamin D in IBD patients, particularly deficiency (68.4%). There seems to exist an association between lower levels of vitamin D and higher disease activity, especially in CD.


INTRODUÇÃO: A deficiáncia de vitamina D é mais comum na doença inflamatória intestinal (DII) que na população geral. Contudo, existem dados controversos sobre fatores preditivos da deficiáncia de vitamina D e a potencial associação com a atividade da doença. Os objetivos deste estudo foram determinar a prevaláncia e fatores preditivos da deficiáncia de vitamina D e aferir possível associação à atividade da doença. MÉTODOS: Desenhou-se um estudo observacional prospetivo incluindo doentes com DII entre janeiro e julho/2016. Foram consideradas as orientações da The Endocrine Society para definir níveis de 25-hidroxivitamina D (25-OH-D) sérica como: deficientes (< 20 ng/mL, sendo <10 ng/mL deficiáncia grave [DG]), insuficientes (21­29 ng/ mL) e adequados (> 30 ng/mL). RESULTADOS: Foram incluídos 152 doentes (52% homens; 47.2 ± 17.3 anos), dos quais 70% com Doença de Crohn (DC). Do total, 37% estavam medicados com immunossupressores e 17% com biológicos. A maioria (88.2%) estava em ambulatório. O nível sérico de 25-OH-D foi 17.1 ± 8 ng/mL (DC: 16.7 ± 8 ng/mL vs. Colite ulcerosa: 17.6 ± 7 ng/mL, p = 0.1). Verificaram-se níveis inadequados em 90.8% (deficiáncia: 68.4%; insuficiáncia: 22.4%). Registou-se correlação negativa significativa entre níveis de 25-OH-D e idade (r = −0.2, p = 0.04), proteína C-reativa (PCR) (r = −0.22, p = 0.004) e índice Harvey-Bradshaw (iHB) (r = −0.32, p = 0.001). Doentes com DG apresentaram níveis mais elevados de PCR (0.6 vs. 1.4 mg/dL, p = 0.03), velocidade de sedimentação (VS) (22 vs. 31 mm/h, p = 0.03) e iHB (2 vs. 5, p < 0.001), e mais baixos de hemoglobina (13.6 vs. 12.7 g/dL, p = 0.02). Não se verificou associação entre deficiáncia de vitamina D e sexo, tipo, extensão e duração da doença, cirurgia, e outras medidas de atividade da doença como VS, hemoglobina (estas duas exceto para DG), calprotectina fecal ou classificação Truelove e Witts. CONCLUSÕES: Registou-se prevaláncia alta de níveis inadequados de vitamina D na DII, particularmente de deficiáncia (68.4%). Parece existir associação entre níveis mais baixos de vitamina D e maior atividade da doença, nomeadamente na DC.

3.
GE Port J Gastroenterol ; 25(5): 253-257, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30320164

RESUMO

INTRODUCTION: Walled-off necrosis (WON) is a potentially lethal late complication of acute pancreatitis (AP) and occurs in less than 10% of AP cases. It can be located in or outside the pancreas. When infected, the mortality rate increases and can reach 100% if the collection is not drained. Its treatment is complex and includes, at the beginning, intravenous antibiotics, which permit sepsis control and a delay in the therapeutic intervention, like drainage. Nowadays, a minimally invasive approach is advised. Depending on the location of the collection, computed tomography (CT)-guided drainage or endoscopic necrosectomy are the primary options, then complemented by surgical necrosectomy if needed. Infected WON of the abdominal wall has been rarely described in the literature and there is no report of any infection with Citrobacter freundii. CASE: We present the case of a 61-year-old man with necrotizing AP complicated by WON of the left abdominal wall, infected with Citrobacter freundii that was successfully treated with CT-guided percutaneous drainage and intravenous antibiotics. CONCLUSION: Infected WON accounts for considerable mortality and its location in the abdominal wall is rare; it can be treated with antibiotics and CT-guided drainage with no need for further intervention.


INTRODUÇÃO: A necrose pancreática coletada (NPC) é uma complicação potencialmente fatal da pancreatite aguda (PA) e ocorre em menos de 10% dos casos. Pode estar localizada dentro ou fora do pâncreas. Quando infetada, a mortalidade aumenta, podendo atingir os 100% se a coleção não for drenada. O seu tratamento é complexo e inclui, de início, antibioterapia intravenosa que permite o controlo da sepsis e um atraso na terapêutica de intervenção, como a drenagem. Atualmente é aconselhada uma abordagem minimamente invasiva. Dependendo da localização da coleção, a drenagem guiada por tomografia computorizada (TC) ou a necrosectomia endoscópica são as opções de primeira linha, posteriormente complementadas por necrosectomia cirúrgica, caso seja necessário. A NPC infetada na parede abdominal foi raramente descrita na literatura e não existe até ao momento nenhum caso de uma NPC infetada por Citrobacter freundii. CASO: Apresentamos o caso de um doente do sexo masculino de 61 anos com uma PA necrotizante complicada por NPC da parede abdominal esquerda, infetada por Citrobacter freundii, que foi tratada com sucesso através de drenagem percutânea guiada por TC e antibioterapia intravenosa. CONCLUSÃO: A NPC infetada condiciona mortalidade considerável e a sua localização na parede abdominal é rara; pode ser tratada através de antibioterapia e drenagem percutânea guiada por TC, sem necessidade de intervenção posterior.

4.
Curr Top Med Chem ; 18(17): 1428-1453, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30129413

RESUMO

Heterocyclic rings having nitrogen atoms are the molecular fragments most used in drug design by using the tools of medicinal chemistry. The 1,2,4-triazole rings are part of an extensive family of drugs that are in use in the pharmaceutical market. More recently, 1,2,3-triazole rings have begun to arouse the great interest of scientists and therefore, many researches have been developed seeking the synthesis of new substances and their possible biological activities. A number of articles have been published by us and others highlighting the synthetic and biological aspects of 1,2,3-triazoles. The growth of new substances of this class was largely due to the simple and selective synthetic method of 1,2,3- triazole ring developed by Sharpless et al. However, some 1,2,3-triazole cannot be synthesized by this method. This review focuses on other synthetic methods that give access to other variations around the 1,2,3-triazole core. The systematic arrangement in this review explores the possibility of providing practical guidance to alternatives of this heterocycle. It has been divided into sections according to the types of starting materials and reactions.


Assuntos
Triazóis/síntese química , Química Farmacêutica , Química Click , Estrutura Molecular , Triazóis/química
5.
Curr Top Med Chem ; 18(2): 149-156, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29595112

RESUMO

Antimicrobial Resistance (AMR) is a serious problem for the humans since it threatens the effective prevention and treatment of an ever-increasing range of infections caused by bacteria, parasites, viruses and fungi. One way around this problem is to act on the virulence factors, produced by bacteria, which increase their infection effectiveness. In view of these facts, new coumarin derivatives were synthesized and evaluated for their anti-virulence biological activity towards Pseudomonas aeruginosa. The results suggest that coumarin derivatives with a secondary carbon at C-3 position reduces P. aeruginosa growth whereas compounds with one additional substituent have a significant effect over pyocyanin production (10k EC50 7 ± 2 µM; 10l EC50 42 ± 13 µM). Moreover, 10k reduces P. aeruginosa motility and biofilm formation, what is compatible with a quorum sensing related mechanism of action.


Assuntos
Antibacterianos/farmacologia , Cumarínicos/síntese química , Cumarínicos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/metabolismo , Piocianina/biossíntese , Fatores de Virulência/biossíntese , Antibacterianos/síntese química , Antibacterianos/química , Cumarínicos/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Piocianina/química , Relação Estrutura-Atividade , Fatores de Virulência/química
6.
Molecules ; 23(4)2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29596367

RESUMO

Carbene transfer reactions are very important transformations in organic synthesis, allowing the generation of structurally challenging products by catalysed cyclopropanation, cyclopropenation, carbene C-H, N-H, O-H, S-H, and Si-H insertion, and olefination of carbonyl compounds. In particular, chiral and achiral metalloporphyrins have been successfully explored as biomimetic catalysts for these carbene transfer reactions under both homogeneous and heterogeneous conditions. In this work the use of synthetic metalloporphyrins (MPorph, M = Fe, Ru, Os, Co, Rh, Ir, Sn) as homogeneous or heterogeneous catalysts for carbene transfer reactions in the last years is reviewed, almost exclusively focused on the literature since the year 2010, except when reference to older publications was deemed to be crucial.


Assuntos
Metaloporfirinas/química , Metano/análogos & derivados , Metano/química
7.
Curr Top Med Chem ; 18(2): 164-171, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29473510

RESUMO

Sporotrichosis is a serious public health problem in Brazil that affects human patients and domestic animals, mainly cats. Thus, the search for new antifungal agents is required also due to the emergence and to the lack of effective drugs available in the therapeutic arsenal. The aim of this study was to evaluate the in vitro antifungal profile of two synthetic series of coumarin derivatives against Sporothrix schenckii and Sporothrix brasiliensis. The three-components synthetic routes used for the preparation of coumarin derivatives have proved to be quite efficient and compounds 16 and 17 have been prepared in good yields. The inhibitory activity of nineteen synthetic coumarins derivatives 16a-i and 17a-j were evaluated against Sporothrix spp. yeasts and the most potent compounds were 16b and 17i. However, according to concentrations able to inhibit (minimum inhibitory concentrations) and kill (minimum fungicidal concentrations) the cells, 17i was more effective than 16b against Sporothrix spp. Thus, 17i exhibited good antifungal activity against S. brasiliensis and S. schenckii, suggesting that it is an important scaffold for the development of novel antifungal agents.


Assuntos
Antifúngicos/síntese química , Antifúngicos/farmacologia , Cumarínicos/síntese química , Cumarínicos/farmacologia , Sporothrix/efeitos dos fármacos , Antifúngicos/química , Cumarínicos/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Sporothrix/crescimento & desenvolvimento , Relação Estrutura-Atividade
8.
Molecules ; 22(2)2017 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-28212345

RESUMO

New sulfonyl-lapachones were efficiently obtained through the catalytic oxidation of arylthio- and cyclohexylthio-lapachone derivatives with hydrogen peroxide in the presence of a Mn(III) porphyrin complex. The antibacterial activities of the non-oxidized and oxidized lapachone derivatives against the Gram-negative bacteria Escherichia coli and the Gram-positive bacteria Staphylococcus aureus were evaluated after their incorporation into polyvinylpyrrolidone (PVP) micelles. The obtained results show that the PVP-formulations of the lapachones 4b-g and of the sulfonyl-lapachones 7e and 7g reduced the growth of S. aureus.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/síntese química , Catálise , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Naftoquinonas/química , Naftoquinonas/farmacologia , Oxirredução , Ácidos Sulfínicos/química
9.
Bioorg Med Chem ; 23(15): 4763-4768, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26118339

RESUMO

We report herein a straightforward and efficient one-step reaction to prepare new nor-ß-lapachone derivatives tethered with phenylthio groups at position 3 of the furan ring. We have screened the compounds on bloodstream trypomastigotes of Trypanosoma cruzi, the causative agent of Chagas disease, aimed at finding a new prototype with high trypanocidal activity. The new compounds possess a broad range of activity (IC50/24h from 9.2 to 182.7 µM), higher than the original quinone (391.5 µM) and four of them higher than standard drug benznidazole (103.6 µM). The most active was compound 13b (9.2 µM), being 11 times active than benznidazole and the less toxic derivative to heart muscle cells.


Assuntos
Benzofuranos/química , Naftoquinonas/química , Tripanossomicidas/síntese química , Animais , Benzofuranos/uso terapêutico , Benzofuranos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Doença de Chagas/tratamento farmacológico , Embrião de Mamíferos/citologia , Coração/efeitos dos fármacos , Humanos , Camundongos , Miocárdio/citologia , Miocárdio/metabolismo , Naftoquinonas/uso terapêutico , Naftoquinonas/toxicidade , Relação Estrutura-Atividade , Tripanossomicidas/uso terapêutico , Tripanossomicidas/toxicidade , Trypanosoma cruzi/efeitos dos fármacos
10.
Eur J Med Chem ; 84: 708-17, 2014 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-25064348

RESUMO

Leukemia is the most common blood cancer, and its development starts at diverse points, leading to distinct subtypes that respond differently to therapy. This heterogeneity is rarely taken into account in therapies, so it is still essential to look for new specific drugs for leukemia subtypes or even for therapy-resistant cases. Naphthoquinones (NQ) are considered privileged structures in medicinal chemistry due to their plethora of biological activities, including antimicrobial and anticancer effects. Nitrogen-containing heterocycles such as 1,2,3-1H-triazoles have been identified as general scaffolds for generating glycosidase inhibitors. In the present study, the NQ and 1,2,3-1H-triazole cores have been combined to chemically synthesize 18 new 1,2-furanonaphthoquinones tethered to 1,2,3-1H-triazoles (1,2-FNQT). Their cytotoxicities were evaluated against four different leukemia cell lines, including MOLT-4 and CEM (lymphoid cell lines) and K562 and KG1 (myeloid cell lines), as well as normal human peripheral blood mononucleated cells (PBMCs). The new 1,2-FNQT series showed high cytotoxic potential against all leukemia cell lines tested, and some compounds (12o and 12p) showed even better results than the classical therapeutic compounds such as doxorubicin or cisplatin. Others compounds, such as 12b, are promising because of their high selectivity against lymphoblastic leukemia and their low activity against normal hematopoietic cells. The cells of lymphoid origin (MOLT and CEM) were generally more sensitive than the myeloid cell lines to this series of compounds, and most of the compounds that showed the highest cytotoxicity were similarly active against both cell lines.


Assuntos
Furanos/síntese química , Furanos/farmacologia , Leucemia Linfoide/patologia , Leucemia Mieloide/patologia , Naftoquinonas/síntese química , Naftoquinonas/farmacologia , Triazóis/química , Triazóis/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Furanos/química , Humanos , Células K562 , Leucemia Linfoide/tratamento farmacológico , Leucemia Mieloide/tratamento farmacológico , Estrutura Molecular , Naftoquinonas/química , Relação Estrutura-Atividade
11.
J Med Chem ; 53(6): 2364-75, 2010 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-20170190

RESUMO

A class of drugs in use for treating type II diabetes mellitus (T2D), typified by the pseudotetrasaccharide acarbose, act by inhibiting the alpha-glucosidase activity present in pancreatic secretions and in the brush border of the small intestine. Herein, we report the synthesis of a series of 4-substituted 1,2,3-triazoles conjugated with sugars, including D-xylose, D-galactose, D-allose, and D-ribose. Compounds were screened for alpha-glucosidase inhibitory activity using yeast maltase (MAL12) as a model enzyme. Methyl-2,3-O-isopropylidene-beta-D-ribofuranosides, such as the 4-(1-cyclohexenyl)-1,2,3-triazole derivative, were among the most active compounds, showing up to 25-fold higher inhibitory potency than the complex oligosaccharide acarbose. Docking studies on a MAL12 homology model disclosed a binding mode consistent with a transition-state-mimicking mechanism. Finally, the actual pharmacological potential of this triazole series was demonstrated by the reduction of postprandial blood glucose levels in normal rats. These compounds could represent new chemical scaffolds for developing novel drugs against T2D.


Assuntos
Carboidratos/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Inibidores de Glicosídeo Hidrolases , Triazóis/química , Sequência de Aminoácidos , Sítios de Ligação , Sequência de Carboidratos , Catálise/efeitos dos fármacos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/metabolismo , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Molecular , Ligação Proteica , Conformação Proteica , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade , Leveduras/enzimologia , Leveduras/genética , alfa-Glucosidases/química , alfa-Glucosidases/metabolismo
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