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1.
Int Orthop ; 46(11): 2693-2704, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35994064

RESUMO

PURPOSE: Osteogrow, an osteoinductive device containing recombinant human Bone Morphogenetic Protein 6 (rhBMP6) in autologous blood coagulum, is a novel therapeutic solution for bone regeneration. This study aimed to evaluate different commercially available calcium phosphate synthetic ceramic particles as a compression-resistant matrix (CRM) added to Osteogrow implants to enhance their biomechanical properties. METHODS: Osteogrow implants with the addition of Vitoss, ChronOs, BAM, and Dongbo ceramics (Osteogrow-C, where C stands for ceramics) were evaluated in the rodent subcutaneous ectopic bone formation assay. Osteogrow-C device was prepared as follows: rhBMP6 was added to blood, and blood was mixed with ceramics and left to coagulate. Osteogrow-C was implanted subcutaneously in the axillary region of Sprague-Dawley rats and the outcome was analyzed 21 days following implantation using microCT, histology, morphometric analyses, and immunohistochemistry. RESULTS: Osteogrow-C implants with all tested ceramic particles induced the formation of the bone-ceramic structure containing cortical bone, the bone between the particles, and bone at the ceramic surfaces. The amount of newly formed bone was significant in all experimental groups; however, the highest bone volume was measured in Osteogrow-C implants with highly porous Vitoss ceramics. The trabecular number was highest in Osteogrow-C implants with Vitoss and ChronOs ceramics while trabeculae were thicker in implants containing BAM and Dongbo ceramics. The immunological response and inflammation were comparable among ceramic particles evaluated in this study. CONCLUSION: Osteogrow-C bone regenerative device was effective with a broad range of commercially available synthetic ceramics providing a promising therapeutic solution for the regeneration of long bone fracture nonunion, large segmental defects, and spinal fusion surgeries.


Assuntos
Proteína Morfogenética Óssea 6 , Osteogênese , Animais , Fosfatos de Cálcio , Cerâmica/farmacologia , Humanos , Ratos , Ratos Sprague-Dawley , Silicatos
2.
Int J Mol Sci ; 23(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35408862

RESUMO

The skin microbiota represents an ecosystem composed of numerous microbial species interacting with each other, as well as with host epithelial and immune cells. The microbiota provides health benefits to the host by supporting essential functions of the skin and inhibiting colonization with pathogens. However, the disturbance of the microbial balance can result in dysbiosis and promote skin diseases, such as atopic dermatitis (AD). This review provides a current overview of the skin microbiota involvement in AD and its complex interplay with host immune response mechanisms, as well as novel therapeutic strategies for treating AD focused on restoring skin microbial homeostasis.


Assuntos
Dermatite Atópica , Microbiota , Dermatite Atópica/terapia , Disbiose , Humanos , Imunidade , Pele
3.
Bioorg Chem ; 95: 103537, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31884142

RESUMO

We present a new efficient green synthetic protocol for introduction of substituents to the C-6 position of 2-arylbenzothiazole nuclei. Newly synthesized compounds were designed to study the influence of the hydroxy and methoxy groups on the 2-arylbenzothiazole scaffold, as well as the influence of the type of substituents placed on the C-6 position of benzothiazole moiety on biological activity, including antibacterial, antitumor and antioxidant activity. Modest activity was observed against the tested Gram-positive and Gram-negative bacterial strains for only amidino derivatives 5d and 6d. The tested compounds exhibited moderate to strong antiproliferative activity towards the tumor cell lines tested. The SAR study revealed that the introduction of substituents into the benzene ring of the benzothiazole nuclei is essential for antiproliferative activity, while introduction of the hydroxy group into the 2-aryl moiety of the 2-arybenzothiazole scaffold significantly improved selectivity against tumor cell lines. The observed results revealed several novel 6-substituted-2-arylbenzothiazole compounds, 5b, 5c, 5f and 6f, with strong and selective antiproliferative activity towards HeLa cells in micro and submicromolar concentrations, with the most selective compounds being 6-ammonium-2-(2-hydroxy/methoxyphenyl)benzothiazoles 5f and 6f. The compound 5f bearing the hydroxy group on the 2-arylbenzothiazole core showed the most promising antioxidative activity evaluated by DPPH, ABTS and FRAP in vitro assays. The presence of the amino protonated group attached at the benzothiazole moiety was essential for the antiproliferative and antioxidant activity observed, exerted through a change in the levels of the reactive oxygen species-modulated HIF-1 protein.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Benzotiazóis/química , Benzotiazóis/farmacologia , Química Verde , Benzotiazóis/síntese química , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão/métodos , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Análise Espectral/métodos , Relação Estrutura-Atividade
4.
Int J Mol Sci ; 21(8)2020 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-32290414

RESUMO

The human microbiota is a diverse microbial ecosystem associated with many beneficial physiological functions as well as numerous disease etiologies. Dominated by bacteria, the microbiota also includes commensal populations of fungi, viruses, archaea, and protists. Unlike bacterial microbiota, which was extensively studied in the past two decades, these non-bacterial microorganisms, their functional roles, and their interaction with one another or with host immune system have not been as widely explored. This review covers the recent findings on the non-bacterial communities of the human gastrointestinal microbiota and their involvement in health and disease, with particular focus on the pathophysiology of inflammatory bowel disease.


Assuntos
Archaea , Bactérias , Microbioma Gastrointestinal , Micobioma , Parasitos , Viroma , Animais , Suscetibilidade a Doenças , Disbiose , Eucariotos , Humanos , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Simbiose
5.
Mol Divers ; 22(3): 637-646, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29557543

RESUMO

Novel nitro (3a-3f)- and amino (4a-4f and 5a-5f)-substituted 2-benzimidazolyl and 2-benzothiazolyl benzo[b]thieno-2-carboxamides were designed and synthesized as potential antibacterial agents. The antibacterial activity of these compounds has been evaluated against Gram-positive (Staphylococcus aureus and Enterococcus faecalis) and Gram-negative bacteria (Escherichia coli and Moraxella catarrhalis). The most promising antibacterial activity was observed for the nitro- and amino-substituted benzimidazole derivatives 3a, 4a, 5a and 5b with MICs 2-8 [Formula: see text]. Additionally, compounds with inferior antibacterial activity were further tested for their antiproliferative activity in vitro against three human cancer cell lines. Amino-substituted benzothiazole hydrochloride salt 5d displayed the most pronounced and selective activity against the MCF-7 cell line with an [Formula: see text] of 40 nM. Furthermore, DNA binding experiments of selected derivatives indicated that DNA cannot be considered as a primary biological target for this type of compounds.


Assuntos
Antibacterianos , Antineoplásicos , Benzimidazóis , Benzotiazóis , Antibacterianos/química , Antibacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Benzimidazóis/química , Benzimidazóis/farmacologia , Benzotiazóis/química , Benzotiazóis/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA/metabolismo , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana , Moraxella catarrhalis/efeitos dos fármacos , Moraxella catarrhalis/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
6.
Int Orthop ; 42(11): 2619-2626, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30219967

RESUMO

Bone fractures represent a significant medical morbidity among aged population with osteoporosis. Bone morphogenetic proteins (BMPs) are suggested to have therapeutic potential to enhance fracture healing in such patients. Though BMP-mediated fracture healing has been well-documented in preclinical models, there has been no clinical study that demonstrated unequivocally that indeed a BMP when presented with an appropriate scaffold could provide basis for robust outcome for delayed or non-union diaphyseal bone fractures. This review presents a comprehensive insight towards the existing knowledge on the role of BMP signaling in bone formation and maintenance. Also therapeutic options based on BMP biology are discussed.A novel osteoinductive autologous bone graft substitute (ABGS) aimed to accelerate bone regeneration was developed and is currently being tested in the clinical setting. It comprises of a biologically compatible autologous carrier made from the patient's peripheral blood (autologous blood coagulum, ABC) and of rhBMP6 as an active ingredient. Such formulation circumvents the use of animal-derived materials, significantly limits inflammatory processes common in commercial bone devices and renders the carrier flexible, malleable, and injectable ensuring the ease of use. The ongoing clinical trials result will provide more detailed insights into the safety, tolerability, pharmacokinetics, and bone healing effects in humans and potentially provide novel and safe therapeutic options for bone repair.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/uso terapêutico , Consolidação da Fratura/efeitos dos fármacos , Fraturas Ósseas/tratamento farmacológico , Animais , Proteínas Morfogenéticas Ósseas/uso terapêutico , Regeneração Óssea/fisiologia , Modelos Animais de Doenças , Consolidação da Fratura/fisiologia , Humanos
7.
Food Technol Biotechnol ; 56(4): 455-463, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30923443

RESUMO

Inflammatory bowel diseases are a group of chronic inflammatory conditions that affect gastrointestinal tract due to inapt and continuous immune activation in response to a myriad of predisposing factors (most notably genetics, environmental impact and gut microbiota composition). It has been shown that vitamin D status can also play a role in the disease pathogenesis, as its deficiency is commonly observed in two major forms of inflammatory bowel diseases - Crohn's disease and ulcerative colitis. Mounting evidence supports the concept of intricate relationship between gut dysbiosis and vitamin D metabolism, while suboptimal levels of this vitamin have been linked to increased clinical disease relapse rates, inadequate response to drugs, as well as decreased quality of life in patients with Crohn's disease and ulcerative colitis. Consequently, the pertinent question is whether increased vitamin D supplementation and (on a population level) food fortification may bring significant benefit to the affected individuals. In this short review we discuss the synthesis, functions, status and food sources of vitamin D, appraise biotechnological facets of vitamin D status analysis and food fortification, and concentrate on novel developments in the field that describe its influence on intestinal microbiota and inflammatory bowel disease.

8.
Antimicrob Agents Chemother ; 60(9): 5337-48, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27353268

RESUMO

As we face an alarming increase in bacterial resistance to current antibacterial chemotherapeutics, expanding the available therapeutic arsenal in the fight against resistant bacterial pathogens causing respiratory tract infections is of high importance. The antibacterial potency of macrolones, a novel class of macrolide antibiotics, against key respiratory pathogens was evaluated in vitro and in vivo MIC values against Streptococcus pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, and Haemophilus influenzae strains sensitive to macrolide antibiotics and with defined macrolide resistance mechanisms were determined. The propensity of macrolones to induce the expression of inducible erm genes was tested by the triple-disk method and incubation in the presence of subinhibitory concentrations of compounds. In vivo efficacy was assessed in a murine model of S. pneumoniae-induced pneumonia, and pharmacokinetic (PK) profiles in mice were determined. The in vitro antibacterial profiles of macrolones were superior to those of marketed macrolide antibiotics, including the ketolide telithromycin, and the compounds did not induce the expression of inducible erm genes. They acted as typical protein synthesis inhibitors in an Escherichia coli transcription/translation assay. Macrolones were characterized by low to moderate systemic clearance, a large volume of distribution, a long half-life, and low oral bioavailability. They were highly efficacious in a murine model of pneumonia after intraperitoneal application even against an S. pneumoniae strain with constitutive resistance to macrolide-lincosamide-streptogramin B antibiotics. Macrolones are the class of macrolide antibiotics with an outstanding antibacterial profile and reasonable PK parameters resulting in good in vivo efficacy.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Macrolídeos/farmacologia , Pneumonia Pneumocócica/tratamento farmacológico , Inibidores da Síntese de Proteínas/farmacologia , Streptococcus pneumoniae/efeitos dos fármacos , Animais , Antibacterianos/farmacocinética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Modelos Animais de Doenças , Farmacorresistência Bacteriana/genética , Escherichia coli/química , Haemophilus influenzae/efeitos dos fármacos , Haemophilus influenzae/crescimento & desenvolvimento , Cetolídeos/farmacologia , Lincosamidas/farmacologia , Macrolídeos/farmacocinética , Masculino , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Pneumonia Pneumocócica/microbiologia , Biossíntese de Proteínas/efeitos dos fármacos , Inibidores da Síntese de Proteínas/farmacocinética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/crescimento & desenvolvimento , Streptococcus pyogenes/efeitos dos fármacos , Streptococcus pyogenes/crescimento & desenvolvimento , Estreptogramina B/farmacologia , Relação Estrutura-Atividade
9.
J Enzyme Inhib Med Chem ; 31(sup2): 104-110, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27319400

RESUMO

A set of novel quinolone-triazole conjugates (12-31) were synthesized in three steps in good yields starting from 2-phenylquinoline-4-carboxylic acid. All the intermediates, as well as the final 1,2,4-triazolyl quinolines were fully characterized by their detailed spectral analysis utilizing different techniques such as IR, 1H NMR, 13C NMR, and finally mass spectrometry. All the synthesized compounds were evaluated in vitro for their potential antibacterial activity and their preliminary safety profile was assessed through cytotoxicity assay. Additionally, six selected conjugates were evaluated for their antioxidative properties on the basis of density functional theory calculations, using radical scavenging assay (DPPH) and cellular antioxidant assay. The reported results encourage further investigation of selected compounds and are shading light on their potential pharmacological use.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Quinolinas/química , Quinolinas/farmacologia , Triazóis/farmacologia , Antibacterianos/síntese química , Antioxidantes/síntese química , Antioxidantes/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Teoria Quântica , Quinolinas/síntese química , Relação Estrutura-Atividade , Triazóis/química
10.
Int J Mol Sci ; 17(4)2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27104515

RESUMO

The healthy intestine represents a remarkable interface where sterile host tissues come in contact with gut microbiota, in a balanced state of homeostasis. The imbalance of gut homeostasis is associated with the onset of many severe pathological conditions, such as inflammatory bowel disease (IBD), a chronic gastrointestinal disorder increasing in incidence and severely influencing affected individuals. Despite the recent development of next generation sequencing and bioinformatics, the current scientific knowledge of specific triggers and diagnostic markers to improve interventional approaches in IBD is still scarce. In this review we present and discuss currently available and emerging therapeutic options in modulating composition and metabolic activity of gut microbiota in patients affected by IBD. Therapeutic approaches at the microbiota level, such as dietary interventions alone or with probiotics, prebiotics and synbiotics, administration of antibiotics, performing fecal microbiota transplantation (FMT) and the use of nematodes, all represent a promising opportunities towards establishing and maintaining of well-being as well as improving underlying IBD symptoms.


Assuntos
Dieta , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais/microbiologia , Animais , Antibacterianos/uso terapêutico , Transplante de Microbiota Fecal , Helmintos/fisiologia , Homeostase , Humanos , Doenças Inflamatórias Intestinais/parasitologia , Doenças Inflamatórias Intestinais/terapia , Fenômenos Fisiológicos da Nutrição , Prebióticos , Probióticos/uso terapêutico , Simbióticos
11.
Bioorg Med Chem ; 23(23): 7448-63, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26578325

RESUMO

Versatile 1,2,3-triazole pharmacophore-based benzofused heterocycles containing halogen-substituted aromatic (9-17 and 25-28), 7-substituted coumarin (18-23 and 29-30) or penciclovir-like subunit (31a,b-38a) were designed and synthesized to evaluate their antibacterial activities against selected Gram-positive and Gram-negative bacteria. Hybridization approach using environmentally friendly Cu(I)-catalyzed click reaction under microwave irradiation was adopted in the synthesis of regioselective 1,4-disubstituted 1,2,3-triazole tethered heterocycles (9-23 and 25-30), while post-N-alkylation of NH-1,2,3-triazoles afforded both 2,4- (31a-38a) and 1,4-disubstituted (31b-33b, 35b-37b) 1,2,3-triazole regioisomers. The compounds 18-23 and 25-30 revealed fluorescence in the violet region of the visible spectrum with a strong influence of phenyl spacer in 25-30 on both wavelength and emission intensity. Fusion of selected subunits led to new hybrid architecture, benzothiazole-1,2,3-triazole-coumarin 29 that demonstrated extremely narrow spectrum activity towards fastidious Gram-negative bacteria Moraxella catarrhalis. Selected hybrid showed the potency against Moraxella catarrhalis (MIC⩽0.25µg/mL) comparable to that of reference antibiotic azithromycin, which suggested that further investigations are necessary to optimize this potential hit compound as a new anti-Moraxella catarrhalis agent.


Assuntos
Antibacterianos/farmacologia , Benzotiazóis/farmacologia , Compostos Heterocíclicos com 2 Anéis/farmacologia , Moraxella catarrhalis/efeitos dos fármacos , Triazóis/farmacologia , Umbeliferonas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Azitromicina/farmacologia , Benzotiazóis/síntese química , Química Click , Compostos Heterocíclicos com 2 Anéis/síntese química , Compostos Heterocíclicos com 2 Anéis/química , Interações Hidrofóbicas e Hidrofílicas , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química , Umbeliferonas/síntese química
12.
Int Orthop ; 38(3): 635-47, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24352822

RESUMO

PURPOSE: The purpose of this study was to revise the clinical use of commercial BMP2 (Infuse) and BMP7 (Osigraft) based bone devices and explore the mechanism of action and efficacy of low BMP6 doses in a novel whole blood biocompatible device OSTEOGROW. METHODS: Complications from the clinical use of BMP2 and BMP7 have been systemically reviewed in light of their role in bone remodeling. BMP6 function has been assessed in Bmp6-/- mice by µCT and skeletal histology, and has also been examined in mesenchymal stem cells (MSC), hematopoietic stem cells (HSC) and osteoclasts. Safety and efficacy of OSTEOGROW have been assessed in rats and rabbits. RESULTS: Clinical use issues of BMP2 and BMP7 have been ascribed to the limited understanding of their role in bone remodeling at the time of device development for clinical trials. BMP2 and BMP7 in bone devices significantly promote bone resorption leading to osteolysis at the endosteal surfaces, while in parallel stimulating exuberant bone formation in surrounding tissues. Unbound BMP2 and BMP7 in bone devices precipitate on the bovine collagen and cause inflammation and swelling. OSTEOGROW required small amounts of BMP6, applied in a biocompatible blood coagulum carrier, for stimulating differentiation of MSCs and accelerated healing of critical size bone defects in animals, without bone resorption and inflammation. BMP6 decreased the number of osteoclasts derived from HSC, while BMP2 and BMP7 increased their number. CONCLUSIONS: Current issues and challenges with commercial bone devices may be resolved by using novel BMP6 biocompatible device OSTEOGROW, which will be clinically tested in metaphyseal bone fractures, compartments where BMP2 and BMP7 have not been effective.


Assuntos
Proteína Morfogenética Óssea 6/farmacologia , Proteína Morfogenética Óssea 6/uso terapêutico , Sistemas de Liberação de Medicamentos , Fraturas Ósseas/tratamento farmacológico , Osteogênese/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Proteína Morfogenética Óssea 2/farmacologia , Proteína Morfogenética Óssea 2/uso terapêutico , Proteína Morfogenética Óssea 6/administração & dosagem , Proteína Morfogenética Óssea 7/farmacologia , Proteína Morfogenética Óssea 7/uso terapêutico , Relação Dose-Resposta a Droga , Fraturas Ósseas/fisiopatologia , Camundongos , Camundongos Knockout , Modelos Animais , Osteogênese/fisiologia , Coelhos , Ratos , Cicatrização/fisiologia
13.
Bioorg Med Chem ; 20(10): 3180-5, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22537683

RESUMO

Xanthones and their thio-derivatives are a class of pleiotropic compounds with various reported pharmacological and biological activities. Although these activities are mainly determined in laboratory conditions, the class itself has a great potential to be utilized as promising chemical scaffold for the synthesis of new drug candidates. One of the main obstacles in utilization of these compounds was related to the difficulties in their chemical synthesis. Most of the known methods require two steps, and are limited to specific reagents not applicable to a large number of starting materials. In this paper a new and improved method for chemical synthesis of xanthones is presented. By applying a new procedure, we have successfully obtained these compounds with the desired regioselectivity in a shorter reaction time (50s) and with better yield (>80%). Finally, the preliminary in vitro screenings on different bacterial species and cytotoxicity assessment, as well as in silico activity evaluation were performed. The obtained results confirm potential pharmacological use of this class of molecules.


Assuntos
Antibacterianos/síntese química , Micro-Ondas , Compostos de Sulfidrila/química , Xantonas/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Simulação por Computador , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Relação Estrutura-Atividade , Xantonas/química , Xantonas/farmacologia
14.
RSC Med Chem ; 13(12): 1504-1525, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36561067

RESUMO

A series of tetrahydropyrimidinyl-substituted benzimidazoles attached to various aliphatic or aromatic residues via phenoxymethylene were synthesised to investigate their antibacterial activities against selected Gram-positive and Gram-negative bacteria. The influence of the type of substituent at the C-3 and C-4 positions of the phenoxymethylene linker on the antibacterial activity was observed, showing that the aromatic moiety improved the antibacterial potency. Of all the evaluated compounds, benzoyl-substituted benzimidazole derivative 15a was the most active compound, particularly against the Gram-negative pathogens E. coli (MIC = 1 µg mL-1) and M. catarrhalis (MIC = 2 µg mL-1). Compound 15a also exhibited the most promising antibacterial activity against sensitive and resistant strains of S. pyogenes (MIC = 2 µg mL-1). Significant stabilization effects and positive induced CD bands strongly support the binding of the most biologically active benzimidazoles inside the minor grooves of AT-rich DNA, in line with docking studies. The predicted physico-chemical and ADME properties lie within drug-like space except for low membrane permeability, which needs further optimization. Our findings encourage further development of novel structurally related 5(6)-tetrahydropyrimidinyl substituted benzimidazoles in order to optimize their antibacterial effect against common respiratory pathogens.

15.
Gut Microbes ; 14(1): 2083419, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35695669

RESUMO

The knowledge on how gut microbes contribute to the inflammatory bowel disease (IBD) at the onset of disease is still scarce. We compared gut microbiota in newly diagnosed, treatment-naïve adult IBD (Crohn's disease (CD) and ulcerative colitis (UC)) to irritable bowel syndrome (IBS) patients and healthy group. Mucosal and fecal microbiota of 49 patients (13 UC, 10 CD, and 26 IBS) before treatment initiation, and fecal microbiota of 12 healthy subjects was characterized by 16S rRNA gene sequencing. Mucosa was sampled at six positions, from terminal ileum to rectum. We demonstrate that mucosal microbiota is spatially homogeneous, cannot be differentiated based on the local inflammation status and yet provides bacterial footprints superior to fecal in discriminating disease phenotypes. IBD groups showed decreased bacterial diversity in mucosa at all taxonomic levels compared to IBS. In CD and UC, Dialister was significantly increased, and expansion of Haemophilus and Propionibacterium characterized UC. Compared to healthy individuals, fecal microbiota of IBD and IBS patients had increased abundance of Proteobacteria, Enterobacteriaceae, in particular. Shift toward reduction of Adlercreutzia and butyrate-producing taxa was found in feces of IBD patients. Microbiota alterations detected in newly diagnosed treatment-naïve adult patients indicate that the microbiota changes are set and detectable at the disease onset and likely have a discerning role in IBD pathophysiology. Our results justify further investigation of the taxa discriminating between disease groups, such as H. parainfluenzae, R. gnavus, Turicibacteriaceae, Dialister, and Adlercreutzia as potential biomarkers of the disease.


Assuntos
Colite Ulcerativa , Doença de Crohn , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Síndrome do Intestino Irritável , Colite Ulcerativa/microbiologia , Doença de Crohn/microbiologia , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Humanos , Doenças Inflamatórias Intestinais/microbiologia , Mucosa Intestinal/microbiologia , RNA Ribossômico 16S/genética
16.
Biomedicines ; 9(10)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34680604

RESUMO

Autologous bone graft substitute (ABGS) containing rhBMP6 in autologous blood coagulum (ABC) with synthetic ceramics is a novel therapeutic solution for bone repair. The aim of this study was to investigate whether the application of Zoledronate (ZOL) with ABGS might enhance the properties of newly formed bone. The effect of ZOL on bone induction was tested in a rat subcutaneous implant model. ZOL bound to synthetic ceramics was added into ABGS implants, and the quantity, quality, and longevity of the induced bone were assessed by micro-CT, histomorphometry, and histology over a period of 365 days. Local use of ZOL in the ABGS implants with ceramics had no influence on the bone volume (BV) on day 14 but subsequently significantly increased BV on days 35, 50, 105, 140, and 365 compared to the control implants. Locally applied ZOL had a similar effect in all of the applied doses (2-20 µg), while its systemic use on stimulating the BV of newly induced bone by ABGS depended on the time of application. BV was increased when ZOL was applied systemically on day 14 but had no effect when applied on day 35. The administration of ZOL bound to ceramics in ABGS increased and maintained the BV over a period of one year, offering a novel bone tissue engineering strategy for treating bone defects and spinal fusions.

17.
Br J Pharmacol ; 178(2): 363-377, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33085774

RESUMO

BACKGROUND AND PURPOSE: Efficacy of current antimalarial treatments is declining as a result of increasing antimalarial drug resistance, so new and potent antimalarial drugs are urgently needed. Azithromycin, an azalide antibiotic, was found useful in malaria therapy, but its efficacy in humans is low. EXPERIMENTAL APPROACH: Four compounds belonging to structurally different azalide classes were tested and their activities compared to azithromycin and chloroquine. in vitro evaluation included testing against sensitive and resistant Plasmodium falciparum, cytotoxicity against HepG2 cells, accumulation and retention in human erythrocytes, antibacterial activity, and mode of action studies (delayed death phenotype and haem polymerization). in vivo assessment enabled determination of pharmacokinetic profiles in mice, rats, dogs, and monkeys and in vivo efficacy in a humanized mouse model. KEY RESULTS: Novel fast-acting azalides were highly active in vitro against P. falciparum strains exhibiting various resistance patterns, including chloroquine-resistant strains. Excellent antimalarial activity was confirmed in a P. falciparum murine model by strong inhibition of haemozoin-containing trophozoites and quick clearance of parasites from the blood. Pharmacokinetic analysis revealed that compounds are metabolically stable and have moderate oral bioavailability, long half-lives, low clearance, and substantial exposures, with blood cells as the preferred compartment, especially infected erythrocytes. Fast anti-plasmodial action is achieved by the high accumulation into infected erythrocytes and interference with parasite haem polymerization, a mode of action different from slow-acting azithromycin. CONCLUSION AND IMPLICATIONS: The hybrid derivatives described here represent excellent antimalarial drug candidates with the potential for clinical use in malaria therapy.


Assuntos
Antimaláricos , Malária , Animais , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Azitromicina/farmacologia , Azitromicina/uso terapêutico , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Cães , Malária/tratamento farmacológico , Camundongos , Plasmodium falciparum , Ratos
18.
Bioorg Med Chem ; 18(9): 3053-8, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20382539

RESUMO

A simple and efficient procedure for the stereoselective synthesis of new azetidinone-isothiazolidinones has been developed. New compounds were tested in vitro on a panel of Gram-positive and Gram-negative bacterial pathogens, some of them showing weak antibacterial activity.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Azetidinas/química , Bactérias/efeitos dos fármacos , Monobactamas/síntese química , Monobactamas/farmacologia , Tiazolidinas/química , Amoxicilina/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Monobactamas/química , Estereoisomerismo
19.
Diagnostics (Basel) ; 11(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375202

RESUMO

The current paradigm of urinary tract infection (UTI) pathogenesis takes into account the contamination of the periurethral space by specific uropathogens residing in the gut, which is followed by urethral colonization and pathogen ascension to the urinary bladder. Consequently, studying the relationship between gut microbiota and the subsequent development of bacteriuria and UTI represents an important field of research. However, the well-established diagnostic and therapeutic paradigm for urinary tract infections (UTIs) has come into question with the discovery of a multifaceted, symbiotic microbiome in the healthy urogenital tract. More specifically, emerging data suggest that vaginal dysbiosis may result in Escherichia coli colonization and prompt recurrent UTIs, while urinary microbiome perturbations may precede the development of UTIs and other pathologic conditions of the urinary system. The question is whether these findings can be exploited for risk reduction and treatment purposes. This review aimed to appraise the three aforementioned specific microbiomes regarding their potential influence on UTI development by focusing on the recent studies in the field and assessing the potential linkages between these different niches, as well as evaluating the state of translational research for novel therapeutic and preventative approaches.

20.
Bone ; 140: 115551, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32730930

RESUMO

Bone morphogenetic proteins (BMPs) are known to induce new bone formation in vivo but treating trabecular bone defects with a BMP based therapeutic remains controversial. Here, we evaluated the safety and efficacy of a novel Autologous Bone Graft Substitute (ABGS) comprised of recombinant human BMP6 (rhBMP6) dispersed within an autologous blood coagulum (ABC) as a physiological natural carrier in patients with a closed distal radial fracture (DRF). We enrolled 32 patients in a randomized, standard of care (SoC) and placebo (PBO) controlled, double-blinded Phase I First in Human (FiH) clinical trial. ABGS was prepared from peripheral blood as 250 µg rhBMP6/mL ABC or PBO (1 mL ABC containing excipients only) and was administered dorsally via a syringe injection into the fracture site following closed fracture fixation with 3 Kirschner wires. Patients carried an immobilization for 5 weeks and were followed-up for 0 to 26 weeks by clinical examination, safety, serial radiographic analyses and CT. During the 13 weeks follow-up and at 26 weeks post study there were no serious adverse reactions recorded. The results showed that there were no detectable anti-rhBMP6 antibodies in the blood of any of the 32 patients at 13- and 26-weeks following treatment. Pharmacokinetic analyses of plasma from patients treated with ABGS showed no detectable rhBMP6 at any time point within the first 24 h following administration. The CT image and radiographic analyses score from patients treated with AGBS showed significantly accelerated bone healing as compared to PBO and SoC at 5 and 9 weeks (with high effect sizes and P = 0.027), while at week 13 all patients had similar healing outcomes. In conclusion, we show that intraosseous administration of ABGS (250 µg rhBMP6/mL ABC) into the distal radial fracture site demonstrated a good tolerability with no serious adverse reactions as well as early accelerated trabecular bone healing as compared to control PBO and SoC patients.


Assuntos
Substitutos Ósseos , Fraturas Fechadas , Proteínas Morfogenéticas Ósseas , Osso Esponjoso , Método Duplo-Cego , Fixação de Fratura , Consolidação da Fratura , Humanos , Resultado do Tratamento
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