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2.
Front Microbiol ; 13: 937970, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36071978

RESUMO

To survive and establish its niche, Mycobacterium tuberculosis (Mtb) engages in a steady battle against an array of host defenses and a barrage of antibiotics. Here, we demonstrate that Mtb employs HupB, a nucleoid-associated protein (NAP) as its key player to simultaneously battle and survive in these two stress-inducing fronts. Typically, NAPs are key to bacterial survival under a wide array of environmental or host-mediated stresses. Here, we report that for Mtb to survive under different macrophage-induced assaults including acidic pH, nutrient depletion, oxidative and nitrosative stresses, HupB presence is critical. As expected, the hupB knockout mutant is highly sensitive to these host-mediated stresses. Furthermore, Mtb aptly modulates HupB protein levels to overcome these stresses. We also report that HupB aids Mtb to gain tolerance to high levels of rifampicin (RIF) and isoniazid (INH) exposure. Loss of hupB makes Mtb highly susceptible to even short exposures to reduced amounts of RIF and INH. Overexpressing hupB in Mtb or complementing hupB in the hupB knockout mutant triggers enhanced survival of Mtb under these stresses. We also find that upon loss of hupB, Mtb significantly enhances the permeability of its cell wall by modulating the levels of several surface lipids including phthiocerol dimycocerosates (PDIMs), thus possibly influencing overall susceptibility to host-mediated stresses. Loss of hupB also downregulates efflux pump expression possibly influencing increased susceptibility to INH and RIF. Finally, we find that therapeutic targeting of HupB with SD1, a known small molecule inhibitor, significantly enhances Mtb susceptibility to INH and THP-1 macrophages and significantly reduces MIC to INH. Thus, our data strongly indicate that HupB is a highly promising therapeutic target especially for potential combinatorial shortened therapy with reduced INH and RIF doses.

3.
Ann Med Surg (Lond) ; 76: 103548, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35495372

RESUMO

Introduction: Among the bariatric surgery procedures, laparoscopic sleeve gastrectomy (LSG) is one of the most common methods for effective and permanent weight loss among patients with severe obesity. Nonetheless, the LSG can be associated with long-term and short-term complications for the patient. The present study is aimed to investigate the effect of Helicobacter pylori on the complications of LSG, to answer the question of whether eradication of Helicobacter pylori in patients undergoing surgery can be effective in reducing postoperative complications. Methods: In the present analytical-cross sectional study, which has been conducted in Shahid Bahonar Hospital in Kerman during 2018-2020, a total of 100 patients (including 38 males and 62 females) with an average age of 34.8 ± 2.4 years and an average BMI of 41.1 ± 3.1 underwent LSG surgery. After the operation, the gastric mucus specimens were taken from all patients for pathological examination of Helicobacter pylori infection. Results: According to the results, 28 patients (28%) tested positive for Helicobacter pylori infection (HP positive), and 72 patients (72%) tested negative in this regard (HP negative). The results indicated no significant difference between the HP positive and HP negative patients in terms of demographic characteristics (age, gender, BMI). Overall, 11 patients (11%) exhibited postoperative complications of the LSG including 7 cases (7%) of the SSI, 2 cases (2%) of intraoperative bleeding, and 2 cases (2%) of leakage [No mortality was reported]. Out of the 11 patients with postoperative complications, 6 patients were HP positive including 4 cases of SSI, 1 case of bleeding, and 1 case of leakage. Conclusions: As indicated by the obtained results, the HP infection has seemingly no impact on the LSG postoperative complications. Nevertheless, it is necessary to conduct further studies on a larger number of patients with a longer follow-up time focusing on the effect of other parameters, such as BMI and underlying diseases.

4.
MethodsX ; 8: 101339, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34430243

RESUMO

The purpose of the study presented in this paper was to develop a customized method for estimating the transmission efficiency of a horizontal light pipe (HLP). The proposal is based on the established method and customized to encompass real incident daylight that horizontal light pipes could collect. Natural incident light is introduced using both direct and diffuse light sources through the temporal parameter of their altitude and azimuth. The temporal parameter is presented as a matrix model consisting of solar altitude and azimuth used in measurement and analysis. Because each location on Earth is characterized by a unique solar altitude and azimuth during the year, the proposed method establishes the measuring template, based on a specific location on Earth and applicable for the HLP. The methodology is supplemented with a theoretical model of an indoor space equipped with an HLP that can be used to analyse data and validate necessary threshold illuminance under real physical conditions. An example of an application of the customized method is demonstrated using a case of light collectors for the HLP light-deflecting panels, the laser-cut panel (LCP).•A method for predicting the transmission efficiency of the HLP for any location and any orientation on a building's façade.•Estimation of transmission efficiency for the HLP implementing a temporal parameter through solar altitude and azimuth.•Resulting data for transmission efficiency for the HLP using a template that is easily applicable for decision-making during a specific period of the year, season or the entire year.

5.
Front Immunol ; 12: 657449, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34456901

RESUMO

The respiratory tract is considered the main port of entry of Mycobacterium leprae, the causative agent of leprosy. However, the great majority of individuals exposed to the leprosy bacillus will never manifest the disease due to their capacity to develop protective immunity. Besides acting as a physical barrier, airway epithelium cells are recognized as key players by initiating a local innate immune response that orchestrates subsequent adaptive immunity to control airborne infections. However, to date, studies exploring the interaction of M. leprae with the respiratory epithelium have been scarce. In this work, the capacity of M. leprae to immune activate human alveolar epithelial cells was investigated, demonstrating that M. leprae-infected A549 cells secrete significantly increased IL-8 that is dependent on NF-κB activation. M. leprae was also able to induce IL-8 production in human primary nasal epithelial cells. M. leprae-treated A549 cells also showed higher expression levels of human ß-defensin-2 (hßD-2), MCP-1, MHC-II and the co-stimulatory molecule CD80. Furthermore, the TLR-9 antagonist inhibited both the secretion of IL-8 and NF-κB activation in response to M. leprae, indicating that bacterial DNA sensing by this Toll-like receptor constitutes an important innate immune pathway activated by the pathogen. Finally, evidence is presented suggesting that extracellular DNA molecules anchored to Hlp, a histone-like protein present on the M. leprae surface, constitute major TLR-9 ligands triggering this pathway. The ability of M. leprae to immune activate respiratory epithelial cells herein demonstrated may represent a very early event during infection that could possibly be essential to the generation of a protective response.


Assuntos
Células Epiteliais Alveolares/imunologia , Células Epiteliais Alveolares/metabolismo , Imunidade Inata , Hanseníase/imunologia , Hanseníase/metabolismo , Mycobacterium leprae/imunologia , Receptor Toll-Like 9/metabolismo , Células A549 , Biomarcadores , Células Cultivadas , Histonas/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunomodulação , Hanseníase/microbiologia , NF-kappa B/metabolismo
6.
s.l; s.n; 2021. 1 - 15 p.
Não convencional em Inglês | CONASS, Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLPROD, Sec. Est. Saúde SP, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1353414

RESUMO

The respiratory tract is considered the main port of entry of Mycobacterium leprae, the causative agent of leprosy. However, the great majority of individuals exposed to the leprosy bacillus will never manifest the disease due to their capacity to develop protective immunity. Besides acting as a physical barrier, airway epithelium cells are recognized as key players by initiating a local innate immune response that orchestrates subsequent adaptive immunity to control airborne infections. However, to date, studies exploring the interaction of M. leprae with the respiratory epithelium have been scarce. In this work, the capacity of M. leprae to immune activate human alveolar epithelial cells was investigated, demonstrating that M. leprae-infected A549 cells secrete significantly increased IL-8 that is dependent on NF-kB activation. M. leprae was also able to induce IL-8 production in human primary nasal epithelial cells. M. leprae-treated A549 cells also showed higher expression levels of human b-defensin-2 (hbD-2), MCP-1, MHC-II and the co-stimulatory molecule CD80. Furthermore, the TLR-9 antagonist inhibited both the secretion of IL-8 and NF-kB activation in response to M. leprae, indicating that bacterial DNA sensing by this Toll-like receptor constitutes an important innate immune pathway activated by the pathogen. Finally, evidence is presented suggesting that extracellular DNA molecules anchored to Hlp, a histone-like protein present on the M. leprae surface, constitute major TLR-9 ligands triggering this pathway. The ability of M. leprae to immune activate respiratory epithelial cells herein demonstrated may represent a very early event during infection that could possibly be essential to the generation of a protective response.(AU)


Assuntos
Humanos , Células Epiteliais Alveolares/imunologia , Células Epiteliais Alveolares/metabolismo , Hanseníase/imunologia , Hanseníase/metabolismo , Mycobacterium leprae/imunologia , Receptores Toll-Like/metabolismo , Imunidade Inata
7.
J Orthop Translat ; 19: 106-117, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31844618

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Oestrogen deficiency, high incidences of hyperlipidaemia (HLP) and accelerated bone loss frequently occur in postmenopausal women. There is an urgent need to develop functional foods or specific drugs to protect against bone loss induced by oestrogen deficiency with HLP. AIM OF THE STUDY: In this study, we investigated the potential inhibitory effects of Sargassum integerrimum (SI) on bone loss in an ovariectomized rat model with HLP. MATERIALS AND METHODS: The rats were treated for 12 weeks, and then, bone mineral density, bone biomechanical, bone microstructure, bone morphology, biomarkers of HLP oxidative stress and side effects were determined. Immunohistochemical staining and Western blot were performed to evaluate related protein expression. RESULTS: The femur bone mineral density increased (P < 0.05), and the microscopic structures (ratio of bone volume to total volume [BV/TV], connectivity density [Conn.D], trabecular number [Tb.N] and trabecular thickness [Tb.Th]) of the bone trabecula and mechanical properties (maximum and breaking load [ML and BL, respectively]) improved after SI treatment (P < 0.05). Furthermore, the levels of HLP biomarkers (total cholesterol, triglyceride and low-density lipoprotein) were significantly decreased (P < 0.05), whereas the levels of antioxidant markers (superoxide dismutase and total antioxidant capacity) were increased (P < 0.05). Similar results were obtained with immunohistochemical staining, whereas the Western blot assay showed that SI stimulated the expression of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in bone. CONCLUSION: Our data indicate that rats exposed to SI treatment for 12 weeks did not exhibit noticeable side effects. In conclusion, SI suppressed bone loss induced by ovariectomized and the associated HLP in rats by activating Nrf2, which could be a promising treatment option for osteoporosis induced by oestrogen deficiency and HLP in postmenopausal women. TRANSLATIONAL SCOPE STATEMENT: Our study verified that SI prevented bone loss in rats with oestrogen deficiency with HLP by upregulating nuclear factor (erythroid-derived 2)-like 2. Furthermore, no side effect was observed after the long-term administration of SI. Those results suggested SI could be developed as a functional food or drug for postmenopausal osteoporosis induced by oestrogen deficiency with HLP.

8.
Microorganisms ; 7(8)2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398798

RESUMO

Dinoflagellates are known to possess a highly aberrant nucleus-the so-called dinokaryon-that exhibits a multitude of exceptional biological features. These include: (1) Permanently condensed chromosomes; (2) DNA in a cholesteric liquid crystalline state, (3) extremely large DNA content (up to 200 pg); and, perhaps most strikingly, (4) a deficit of histones-the canonical building blocks of all eukaryotic chromatin. Dinoflagellates belong to the Alveolata clade (dinoflagellates, apicomplexans, and ciliates) and, therefore, the biological oddities observed in dinoflagellate nuclei are derived character states. Understanding the sequence of changes that led to the dinokaryon has been difficult in the past with poor resolution of dinoflagellate phylogeny. Moreover, lack of knowledge of their molecular composition has constrained our understanding of the molecular properties of these derived nuclei. However, recent advances in the resolution of the phylogeny of dinoflagellates, particularly of the early branching taxa; the realization that divergent histone genes are present; and the discovery of dinoflagellate-specific nuclear proteins that were acquired early in dinoflagellate evolution have all thrown new light nature and evolution of the dinokaryon.

10.
Comput Struct Biotechnol J ; 15: 359-365, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28660014

RESUMO

Apolipoprotein E (apoE), a 34 kDa glycoprotein, mediates hepatic and extrahepatic uptake of plasma lipoproteins and cholesterol efflux from lipid-laden macrophages. In humans, three structural different apoE isoforms occur, with subsequent functional changes and pathological consequences. Here, we review data supporting the involvement of apoE structural domains and isoforms in normal and altered lipid metabolism, cardiovascular and neurodegenerative diseases, as well as stress-related pathological states. Studies using truncated apoE forms provided valuable information regarding the regions and residues responsible for its properties. ApoE3 renders protection against cardiovascular diseases by maintaining lipid homeostasis, while apoE2 is associated with dysbetalipoproteinemia. ApoE4 is a recognized risk factor for Alzheimer's disease, although the exact mechanism of the disease initiation and progression is not entirely elucidated. ApoE is also implicated in infections with herpes simplex type-1, hepatitis C and human immunodeficiency viruses. Interacting with both viral and host molecules, apoE isoforms differently interfere with the viral life cycle. ApoE exerts anti-inflammatory effects, switching macrophage phenotype from the proinflammatory M1 to the anti-inflammatory M2, suppressing CD4+ and CD8+ lymphocytes, and reducing IL-2 production. The anti-oxidative properties of apoE are isoform-dependent, modulating the levels of various molecules (Nrf2 target genes, metallothioneins, paraoxonase). Mimetic peptides were designed to exploit apoE beneficial properties. The "structure correctors" which convert apoE4 into apoE3-like molecules have pharmacological potential. Despite no successful strategy is yet available for apoE-related disorders, several promising candidates deserve further improvement and exploitation.

12.
Nutrients ; 8(6)2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27338465

RESUMO

Hyperlipidemia (HLP) is characterized by a disturbance in lipid metabolism and is a primary risk factor for the development of insulin resistance (IR) and a well-established risk factor for cardiovascular disease and atherosclerosis. The aim of this work was to investigate the changes in postprandial amino acid and biogenic amine profiles provoked by an oral glucose tolerance test (OGTT) in HLP patients using targeted metabolomics. We used ultra-high-performance liquid chromatography-triple quadrupole mass spectrometry to analyze the serum amino acid and biogenic amine profiles of 35 control and 35 HLP subjects during an OGTT. The amino acid and biogenic amine profiles from 30 HLP subjects were detected as independent samples to validate the changes in the metabolites. There were differences in the amino acid and biogenic amine profiles between the HLP individuals and the healthy controls at baseline and after the OGTT. The per cent changes of 13 metabolites from fasting to the 2 h samples during the OGTT in the HLP patients were significantly different from those of the healthy controls. The lipid parameters were associated with the changes in valine, isoleucine, creatine, creatinine, dimethylglycine, asparagine, serine, and tyrosine (all p < 0.05) during the OGTT in the HLP group. The postprandial changes in isoleucine and γ-aminobutyric acid (GABA) during the OGTT were positively associated with the homeostasis model assessment of insulin resistance (HOMA-IR; all p < 0.05) in the HLP group. Elevated oxidative stress and disordered energy metabolism during OGTTs are important characteristics of metabolic perturbations in HLP. Our findings offer new insights into the complex physiological regulation of metabolism during the OGTT in HLP.


Assuntos
Aminoácidos/sangue , Aminas Biogênicas/sangue , Teste de Tolerância a Glucose , Hiperlipidemias/sangue , Metabolômica , Adulto , Glicemia/metabolismo , Estudos de Casos e Controles , Carboidratos da Dieta/administração & dosagem , Ingestão de Energia , Exercício Físico , Feminino , Humanos , Insulina/sangue , Resistência à Insulina , Isoleucina/sangue , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial/fisiologia , Reprodutibilidade dos Testes , Fatores de Risco , Ácido gama-Aminobutírico/sangue
13.
Acta Crystallogr F Struct Biol Commun ; 72(Pt 4): 257-62, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27050257

RESUMO

Nucleoid-associated proteins (NAPs) in prokaryotes play an important architectural role in DNA bending, supercoiling and DNA compaction. In addition to architectural roles, some NAPs also play regulatory roles in DNA replication and repair, and act as global transcriptional regulators in many bacteria. Bacteria encode multiple NAPs and some of them are even essential for survival. Streptococcus mutans, a dental pathogen, encodes one such essential NAP called histone-like protein (HLP). Here, the three-dimensional structure of S. mutans HLP has been determined to 1.9 Šresolution. The HLP structure is a dimer and shares a high degree of similarity with other bacterial NAPs, including HU. Since HLPs are essential for the survival of pathogenic streptococci, this structure determination is potentially beneficial for future drug development against these pathogens.


Assuntos
Proteínas de Bactérias/química , Histonas/química , Streptococcus mutans/química , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Dimerização , Genes Bacterianos , Histonas/genética , Modelos Moleculares , Conformação Proteica , Homologia de Sequência de Aminoácidos , Streptococcus mutans/genética
14.
Int J Pharm ; 453(2): 601-9, 2013 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-23742977

RESUMO

In this study an extraction procedure using molecular imprinted polymer nanoparticles for the determination of haloperidol in biological samples is proposed. The haloperidol imprinted polymer nanoparticles were synthesized successfully by precipitation polymerization in a flask containing haloperidol as a template, ethyleneglycoldimethacrylate as a crosslinking agent, methacrylic acid as a functional monomer, and 2,2'-azobisisobutyronitrile as an initiator. The leached and unleached polymer nanoparticles have been characterized by infrared spectroscopy and scanning electron microscopy. The effect of different variables such as the pH of solution, uptake and elution time, type, and the least amount of eluent for elution of haloperidol from polymer was evaluated. Extraction efficiencies more than 97% were obtained by elution of the polymer with 1.5 mL of methanol-acetic acid-trifluoroacetic acid 79.9:20:0.1. Under optimal conditions maximum adsorption capacity was obtained 153.84 mg g(-1). The detection limit of the proposed procedure was between 0.2 and 0.35 µg L(-1). Finally this method was applied to the determination of haloperidol in plasma and urine samples and satisfactory results were achieved (RSD<6.9%).


Assuntos
Antipsicóticos/sangue , Antipsicóticos/urina , Haloperidol/sangue , Haloperidol/urina , Impressão Molecular , Nanopartículas/química , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Microscopia Eletrônica de Varredura , Nanopartículas/ultraestrutura , Polímeros , Extração em Fase Sólida/métodos
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