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1.
Biochim Biophys Acta Mol Basis Dis ; 1870(3): 166991, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38128843

RESUMO

Hirschsprung disease (HSCR) is a complex genetic disorder characterized by the absence of enteric nervous system (ENS) in the distal region of the intestine. Down Syndrome (DS) patients have a >50-fold higher risk of developing HSCR than the general population, suggesting that overexpression of human chromosome 21 (Hsa21) genes contribute to HSCR etiology. However, identification of responsible genes remains challenging. Here, we describe a genetic screening of potential candidate genes located on Hsa21, using the zebrafish. Candidate genes were located in the DS-HSCR susceptibility region, expressed in the human intestine, were known potential biomarkers for DS prenatal diagnosis, and were present in the zebrafish genome. With this approach, four genes were selected: RCAN1, ITSN1, ATP5PO and SUMO3. However, only overexpression of ATP5PO, coding for a component of the mitochondrial ATPase, led to significant reduction of ENS cells. Paradoxically, in vitro studies showed that overexpression of ATP5PO led to a reduction of ATP5PO protein levels. Impaired neuronal differentiation and reduced mitochondrial ATP production, were also detected in vitro, after overexpression of ATP5PO in a neuroblastoma cell line. Finally, epistasis was observed between ATP5PO and ret, the most important HSCR gene. Taken together, our results identify ATP5PO as the gene responsible for the increased risk of HSCR in DS patients in particular if RET variants are also present, and show that a balanced expression of ATP5PO is required for normal ENS development.


Assuntos
Síndrome de Down , Sistema Nervoso Entérico , Doença de Hirschsprung , Animais , Humanos , Doença de Hirschsprung/genética , Doença de Hirschsprung/metabolismo , Síndrome de Down/genética , Síndrome de Down/metabolismo , Peixe-Zebra/genética , Sistema Nervoso Entérico/metabolismo , Biomarcadores/metabolismo
2.
Sci Rep ; 11(1): 16350, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381104

RESUMO

Thermophilic biohydrogen production by dark fermentation from a mixture (1:1) of C5 (arabinose) and C6 (glucose) sugars, present in lignocellulosic hydrolysates, and from Sargassum sp. biomass, is studied in this work in batch assays and also in a continuous reactor experiment. Pursuing the interest of studying interactions between inorganic materials (adsorbents, conductive and others) and anaerobic bacteria, the biological processes were amended with variable amounts of a zeolite type-13X in the range of zeolite/inoculum (in VS) ratios (Z/I) of 0.065-0.26 g g-1. In the batch assays, the presence of the zeolite was beneficial to increase the hydrogen titer by 15-21% with C5 and C6-sugars as compared to the control, and an increase of 27% was observed in the batch fermentation of Sargassum sp. Hydrogen yields also increased by 10-26% with sugars in the presence of the zeolite. The rate of hydrogen production increased linearly with the Z/I ratios in the experiments with C5 and C6-sugars. In the batch assay with Sargassum sp., there was an optimum value of Z/I of 0.13 g g-1 where the H2 production rate observed was the highest, although all values were in a narrow range between 3.21 and 4.19 mmol L-1 day-1. The positive effect of the zeolite was also observed in a continuous high-rate reactor fed with C5 and C6-sugars. The increase of the organic loading rate (OLR) from 8.8 to 17.6 kg m-3 day-1 of COD led to lower hydrogen production rates but, upon zeolite addition (0.26 g g-1 VS inoculum), the hydrogen production increased significantly from 143 to 413 mL L-1 day-1. Interestingly, the presence of zeolite in the continuous operation had a remarkable impact in the microbial community and in the profile of fermentation products. The effect of zeolite could be related to several properties, including the porous structure and the associated surface area available for bacterial adhesion, potential release of trace elements, ion-exchanger capacity or ability to adsorb different compounds (i.e. protons). The observations opens novel perspectives and will stimulate further research not only in biohydrogen production, but broadly in the field of interactions between bacteria and inorganic materials.

3.
Bioelectrochemistry ; 132: 107413, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31816578

RESUMO

Microbiologically influenced corrosion (MIC) of bare and silane-TiO2 sol-gel coated stainless steel (SS) was studied in treated urban wastewater (TUWW). Combining the electrochemical impedance spectroscopy (EIS) and the scanning vibrating electrode technique (SVET) showed that SS surface colonization occurs, at earlier stages, by iron-oxidizing bacteria (IOB), and later by sulphate-reducing bacteria (SRB). The SVET results showed that chemical corrosion process and bacterial respiration led to the depletion of dissolved oxygen, creating a differential aeration cell and thus a localized corrosion phenomenon. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) showed that the growth of a bacterial biofilm on 304L SS was a dynamic process, stimulating the localized oxidation of SS. To improve corrosion protection, a silane-TiO2 sol-gel coating for SS is proposed. SEM showed that the coating reduced bacterial adhesion and EIS study demonstrated that the coating improved the barrier properties and corrosion resistance of 304L SS in TUWW over a short period of immersion.


Assuntos
Bactérias/metabolismo , Corrosão , Silanos/química , Aço Inoxidável , Titânio/química , Águas Residuárias , Aderência Bacteriana , Microbiologia da Água
4.
Braz. j. biol ; 78(2): 271-280, May-Aug. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888875

RESUMO

Abstract Sepsis induces a severe systemic inflammatory response that may result in multiple organ dysfunction and death. Studies using a protein derived from natural Hevea brasiliensis (rubber tree) latex, denominated Hev b 13, have demonstrated important anti-inflammatory effects, but no data have been published regarding its effects on sepsis. The aim of this study was to investigate the effects of Hev b 13 on the inflammatory response and lung lesions of septal rats. Male Wistar rats were submitted to cecal ligation and puncture (CLP), randomized into groups and treated with subcutaneously administered doses of 0.5/2.0/3.0 mg/Kg of Hev b 13. Next, animals were subdivided into three different points in time (1, 6 and 24 hours after treatments) for collection of blood samples and euthanasia accompanied by organ removal. Total and differential leukocyte counts, cytokine dosage and histological assessment were analyzed. Treatment with Hev b 13 resulted in a significant decline in total and differential leukocytes as well as suppression of TNF-α and IL-6 production, associated with the increase in IL-10 and IL-4 in plasma and lung tissue. Moreover, it reduced morphological and pathological changes found in the lungs, including neutrophil infiltration, edema and alveolar thickening. The present study concluded that Hev b 13 exerts anti-inflammatory effects and attenuates lung lesions in septal rats, showing potential for clinical application.


Resumo Sepse induz uma resposta inflamatória sistêmica grave podendo resultar em disfunção de múltiplos órgãos e morte. Pesquisas utilizando uma proteína derivada do látex natural de Hevea brasiliensis (seringueira), denominada Hev b 13 tem demonstrado importantes efeitos anti-inflamatórios, mas nenhum dado foi publicado dos seus efeitos na sepse. O objetivo deste estudo foi investigar os efeitos da Hev b 13 na resposta inflamatória e na lesão pulmonar de ratos com sepse. Ratos machos da linhagem Wistar foram submetidos a ligação e perfuração do ceco (LPC), randomizados em grupos e tratados com as doses 0,5/2,0/3,0 mg/Kg de Hev b 13 subcutâneo. Após subdividiu-se os animais em três pontos diferentes de tempo (1, 6 e 24 horas após os tratamentos) para coleta de amostras sanguíneas e eutanásia com remoção dos órgãos. Contagem total e diferencial de leucócitos, dosagem de citocinas e avaliação histológica foram analisadas. O tratamento com a Hev b 13 resultou em diminuição significativa de leucócitos totais e diferenciais bem como suprimiu a produção de TNF-α e IL-6, associado ao aumento de IL-10 e IL-4 no plasma e tecido pulmonar. Além disso, reduziu as alterações morfológicas e patológicas encontradas nos pulmões, incluindo infiltrado de neutrófilos, edema e espessamento alveolar. Este estudo concluiu que a Hev b 13 tem efeitos anti-inflamatórios e atenua lesões pulmonares em ratos com sepse, apresentando potencialidades para aplicabilidade clínica.


Assuntos
Animais , Masculino , Ratos , Proteínas de Plantas/farmacologia , Antígenos de Plantas/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/metabolismo , Pneumopatias/metabolismo , Proteínas de Plantas/administração & dosagem , Distribuição Aleatória , Citocinas/imunologia , Citocinas/metabolismo , Citocinas/sangue , Ratos Wistar , Sepse/metabolismo , Modelos Animais de Doenças , Antígenos de Plantas/administração & dosagem , Pneumopatias/imunologia
5.
J Mater Chem B ; 6(18): 2821-2830, 2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32254235

RESUMO

Zinc (Zn)-derived foams have been prepared from an alkaline electrolyte solution by galvanostatic electrodeposition under different conditions. A detailed physico-chemical characterization was performed by Raman spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). A pioneer application of these foams in medical implant-related applications was investigated. The in vitro behaviour of these Zn-derived foams in simulated physiological conditions was studied. The results revealed that the presence of zinc oxide was important enough to change the in vitro behaviour of these materials. The potential of these Zn-derived foams in inhibiting bone cancer cell proliferation - osteoscarcoma cells - and important pathogenic fungi responsible for implant-related infections -Candida albicans- was examined. Furthermore, the foams were evaluated for cytocompatibility with normal human osteoblasts. The results obtained allowed us to conclude that Zn-derived foams have an interesting potential for anti-cancer and anti-Candida activity, targeted for bone-related implant applications, suggesting that this novel material may have potential for further clinical studies.

6.
Bioresour Technol ; 175: 480-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25459858

RESUMO

A design of experiments was adopted to assess the optimal conditions for methane production from the macroalgae Sargassum sp. co-digested with glycerol (Gly) and waste frying oil (WFO). Three variables were tested: % total solids of algae (%TSSargassumsp.), co-substrate concentration (gGly/WFOL(-1)), and co-substrate type (Gly or WFO). The biochemical methane potential (BMP) of Sargassum sp. was 181±1L CH4kg(-1) COD. The co-digestion with Gly and WFO increased the BMP by 56% and 46%, respectively. The methane production rate (k), showed similar behaviour as the BMP, increasing 38% and 19% with Gly and WFO, respectively. The higher BMP (283±18L CH4kg(-1) COD) and k (65.9±2.1L CH4kg(-1) CODd(-1)) was obtained in the assay with 0.5% TS and 3.0gGlyL(-1). Co-digestion with glycerol or WFO is a promising process to enhance the BMP from the macroalgae Sargassum sp.


Assuntos
Biocombustíveis , Gorduras Insaturadas na Dieta/metabolismo , Glicerol/metabolismo , Metano/biossíntese , Sargassum/metabolismo , Anaerobiose , Calibragem , Culinária , Fermentação , Glicerol/química , Hidrólise , Projetos de Pesquisa/normas , Sargassum/química , Alga Marinha/química , Alga Marinha/metabolismo
7.
Water Res ; 43(20): 5142-50, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19846190

RESUMO

Different concentrations of oily waste were added in a discontinuous mode and recurrently to anaerobic continuous stirred tank reactors fed with cow manure and food waste. Four continuous stirred tank reactors were run in parallel. A control reactor (R1) received no additional oil and R2, R3 and R4 received increasing concentrations of oil in two different experimental approaches. First, the lipids composition was forced to change suddenly, in three moments, without changing the total chemical oxygen demand (COD) fed to the reactors. The only long chain fatty acid (LCFA) detected onto the R1 solid matrix was palmitic acid (C16:0). Nevertheless in the solid matrix of R2, R3 and R4C16:0 and stearic acid were detected. For occasional increase in the oil concentration up to 7.7gCOD(oil)/L(reactor) (55% Oil(COD)/Total(COD)) no statistical differences were detected between the reactors, in terms of methane production, effluent soluble COD, effluent volatile fatty acids and total and volatile solids removal. Therefore this experiment allowed to conclude that cow manure-food waste co-digestion presents sufficient buffer capacity to endure solid-associated LCFA concentration up to 20-25gCOD-LCFA/kgTS. In a second experiment higher concentrations of oil were added, raising occasionally the concentration in the reactors to 9, 12, 15 and 18gCOD(oil)/L(reactor). All pulses had a positive effect in methane production, with the exception of the highest oil pulse concentration, that persistently impaired the reactor performance. This experiment demonstrates that threshold values for LCFA and C16:0 accumulation onto the solid matrix, of about 180-220gCOD-LCFA/kgTS and 120-150gCOD-C16:0/kgTS, should not be surpassed in order to prevent persistent reactor failure, as occurs in some full scale co-digestion plants.


Assuntos
Ácidos Graxos/análise , Alimentos , Esterco , Óleos/análise , Eliminação de Resíduos/métodos , Animais , Biodegradação Ambiental , Reatores Biológicos , Bovinos , Ácidos Graxos/química , Metano/análise
8.
Eur J Gynaecol Oncol ; 26(2): 163-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15857021

RESUMO

OBJECTIVES: Retrospective evaluation of the clinical behavior, treatment and prognosis in five cases of primary breast lymphoma. METHODS: From 1999 to 2003, five patients with primary breast lymphoma were diagnosed in our department. RESULTS: Primary breast lymphoma (PBL) was diagnosed in five patients, whose median age was 63.4 (41-79) years. In four out of five patients, a diagnosis of lymphoma was made after the evaluation of a palpable breast mass measuring 1.5 to 6 cm. All of them were classified as non-Hodgkin's B cell lymphomas and three of five cases were diffuse large cell lymphomas. All patients were submitted to chemotherapy; in only one patient was surgery performed. CONCLUSIONS: A relatively high rate of PBL was observed in our department compared with other oncology centers. Beyond its scarce appearance, PBL is very difficult to distinguish from primary breast carcinoma. Histology remains the major diagnostic tool.


Assuntos
Neoplasias da Mama/diagnóstico , Linfoma de Células B/diagnóstico , Adulto , Idoso , Neoplasias da Mama/terapia , Feminino , Humanos , Linfoma de Células B/terapia , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
Acta Med Port ; 3(4): 253-4, 1990.
Artigo em Português | MEDLINE | ID: mdl-2275419

RESUMO

The new methods of endoscopic hemostasis for bleeding gastric or duodenal ulcers are discussed. These techniques are increasingly important in patients with high risk for surgery. Due to its low cost, technical simplicity and a success rate similar to the other methods, endoscopic sclerosis is probably the first choice therapy for these conditions.


Assuntos
Úlcera Duodenal/complicações , Úlcera Péptica Hemorrágica/terapia , Escleroterapia/métodos , Úlcera Gástrica/complicações , Endoscopia Gastrointestinal , Humanos , Úlcera Péptica Hemorrágica/etiologia
11.
Gegenbaurs Morphol Jahrb ; 129(5): 575-92, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6653999

RESUMO

The ovary of the tilapia Oreochromis niloticus was studied morphologically and morphometrically; the zonas granulosa and radiata, the ooplasm and the yolk globules were studied histochemically. The ovary is of typical teleostean type consisting of a wall and developing oocytes. The development of oocytes has been divided into 10 cytological stages. Histochemically the zona radiata and yolk globules contain glycoprotein (neutral mucopolysaccharides and protein radicals alpha-amino groups, cystine, cystein, tyrosin, tryptophane, and arginine. The zona granulosa and ooplasm contain neutral and carboxylate acid mucopolysaccharides and protein radicals alpha-amino group, cystein, cystine, tyrosin, arginine, and tryptophane.


Assuntos
Peixes/embriologia , Oócitos/crescimento & desenvolvimento , Animais , Feminino , Histocitoquímica , Oócitos/análise , Oócitos/ultraestrutura
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