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1.
Appl Environ Microbiol ; 85(2)2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30366998

RESUMEN

Degradation of long-chain fatty acids (LCFAs) in methanogenic environments is a syntrophic process involving the activity of LCFA-degrading bacteria and hydrogen-utilizing methanogens. If methanogens are inhibited, other hydrogen scavengers are needed to achieve complete LCFA degradation. In this work, we developed two different oleate (C18:1 LCFA)-degrading anaerobic enrichment cultures, one methanogenic (ME) and another in which methanogenesis was inhibited (IE). Inhibition of methanogens was attained by adding a solution of 2-bromoethanesulfonate (BrES), which turned out to consist of a mixture of BrES and isethionate. Approximately 5 times faster oleate degradation was accomplished by the IE culture compared with the ME culture. A bacterium closely related to Syntrophomonas zehnderi (99% 16S rRNA gene identity) was the main oleate degrader in both enrichments, in syntrophic relationship with hydrogenotrophic methanogens from the genera Methanobacterium and Methanoculleus (in ME culture) or with a bacterium closely related to Desulfovibrio aminophilus (in IE culture). A Desulfovibrio species was isolated, and its ability to utilize hydrogen was confirmed. This bacterium converted isethionate to acetate and sulfide, with or without hydrogen as electron donor. This bacterium also utilized BrES but only after 3 months of incubation. Our study shows that syntrophic oleate degradation can be coupled to desulfonation.IMPORTANCE In anaerobic treatment of complex wastewater containing fat, oils, and grease, high long-chain fatty acid (LCFA) concentrations may inhibit microbial communities, particularly those of methanogens. Here, we investigated if anaerobic degradation of LCFAs can proceed when methanogens are inhibited and in the absence of typical external electron acceptors, such as nitrate, iron, or sulfate. Inhibition studies were performed with the methanogenic inhibitor 2-bromoethanesulfonate (BrES). We noticed that, after autoclaving, BrES underwent partial hydrolysis and turned out to be a mixture of two sulfonates (BrES and isethionate). We found out that LCFA conversion proceeded faster in the assays where methanogenesis was inhibited, and that it was dependent on the utilization of isethionate. In this study, we report LCFA degradation coupled to desulfonation. Our results also showed that BrES can be utilized by anaerobic bacteria.


Asunto(s)
Ácidos Alcanesulfónicos/metabolismo , Clostridiales/metabolismo , Desulfovibrio/metabolismo , Methanobacterium/metabolismo , Methanomicrobiaceae/metabolismo , Ácido Oléico/metabolismo , Anaerobiosis/efectos de los fármacos
2.
Parasitology ; 146(6): 753-764, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30561285

RESUMEN

Hepatocytes constitute the majority of hepatic cells, and play a key role in controlling systemic innate immunity, via pattern-recognition receptors (PRRs) and by synthesizing complement and acute phase proteins. Leishmania infantum, a protozoan parasite that causes human and canine leishmaniasis, infects liver by establishing inside the Kupffer cells. The current study proposes the elucidation of the immune response generated by dog hepatocytes when exposed to L. infantum. Additionally, the impact of adding leishmanicidal compound, meglumine antimoniate (MgA), to parasite-exposed hepatocytes was also addressed. L. infantum presents a high tropism to hepatocytes, establishing strong membrane interactions. The possibility of L. infantum internalization by hepatocytes was raised, but not confirmed. Hepatocytes were able to recognize parasite presence, inducing PRRs [nucleotide oligomerization domain (NOD)1, NOD2 and Toll-like receptor (TLR)2] gene expression and generating a mix pro- and anti-inflammatory cytokine response. Reduction of cytochrome P 450s enzyme activity was also observed concomitant with the inflammatory response. Addition of MgA increased NOD2, TLR4 and interleukin 10 gene expression, indicating an immunomodulatory role for MgA. Hepatocytes seem to have a major role in coordinating liver's innate immune response against L. infantum infection, activating inflammatory mechanisms, but always balancing the inflammatory response in order to avoid cell damage.

3.
Pancreatology ; 18(3): 298-303, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29452754

RESUMEN

BACKGROUND/OBJECTIVES: Insulinoma is a rare pancreatic tumor and, usually, a benign disease but can be a malignant one and, sometimes, a highly aggressive disease. The aim of this study was to determine differences between benign and malignant tumors. METHODS: Retrospective study of 103 patients with insulinoma treated in a tertiary center. It was analyzed demographic, clinical, laboratory, localization and histologic analysis of tumor and follow up data of subjects in order to identify differences between individuals benign and malignant disease. RESULTS: Almost all patients (87%) had a benign tumor and survival rates of 100% following pancreatic tumor surgery. Those with malignant tumors (13%) have a poor prognosis, 77% insulinoma-related deaths over a period of 1-300 months after the diagnosis with a survival rate of 24% in five years. The following factors are associated with an increased risk of malignant disease: duration of symptoms < 24 months, fasting time for the occurrence of hypoglycemia < 8 h, blood plasma insulin concentration ≥ 28 µU/mL and C-peptide ≥ 4.0 ng/mL at the glycemic nadir and tumor size ≥ 2.5 cm. CONCLUSIONS: Our data help to base the literature about these tumors, reinforcing that although insulinoma is usually a single benign and surgically treated neoplasia, the malignant one is difficult to treat. We highlight the data that help predict a malignancy behavior of tumor and suggest a long follow up after diagnosis in these cases.


Asunto(s)
Insulinoma/patología , Neoplasias Pancreáticas/patología , Adulto , Anciano , Glucemia/análisis , Péptido C/análisis , Estudios de Cohortes , Femenino , Humanos , Hipoglucemia/etiología , Insulina/sangre , Insulinoma/cirugía , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Neoplasia Endocrina Múltiple/patología , Neoplasia Endocrina Múltiple/cirugía , Neoplasias Pancreáticas/cirugía , Estudios Retrospectivos , Factores de Riesgo , Análisis de Supervivencia , Adulto Joven
4.
Tech Coloproctol ; 21(9): 745-754, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28819868

RESUMEN

BACKGROUND: Neoadjuvant chemoradiation therapy (nCRT) for rectal cancer may lead to cure. As we currently lack reliable methods to clinically confirm the absence of disease, some patients undergo radical resection and have pathological complete response (pCR) still undergo surgery. Furthermore, it is uncertain if conventional one-level histopathological analysis is accurate enough to determine complete response. Confirming pCR is essential to determine the prognosis and to consider the patient's inclusion in trials of adjuvant therapy. The aim of this study was to determine whether the current 1-level approach is sufficient to confirm pCR. METHODS: Four hundred and thirty-five patients with rectal cancer who received nCRT followed by radical resection were analyzed. All cases identified as pCR by 1-level step section histological evaluation were reassessed with 3-level step sections and immunohistochemical analysis to verify the presence of residual disease. RESULTS: Out of 435 patients, 75 (17.2%) were staged as ypT0. Of these, 6 had lymph node involvement and 1 had distant metastasis, leaving 68 (15.6%) who had pCR. After the additional step sections, residual tumor was detected in 12 (17.6%) of these 68. The final pCR rate was 12.9%. Distant recurrence was detected in 7.1% of real-pCR patients compared to 16.7% in the false-pCR group (p = 0.291). Sensitivity of clinical assessment for detecting pCR was 35.7%, and the accuracy of 1-section histological evaluation to identify pCR was 82.4%. CONCLUSIONS: Histopathological analysis with 1-level step section is insufficient to determine complete tumor eradication. The 3-level sections methodology revealed residual tumor cells in patients initially classified as ypT0. Further studies with larger sample size are required to verify the clinical relevance of these residual tumor cells. Caution should continue to be applied to watch and wait strategies following nCRT.


Asunto(s)
Quimioradioterapia Adyuvante/métodos , Terapia Neoadyuvante/métodos , Recurrencia Local de Neoplasia/diagnóstico , Neoplasia Residual/diagnóstico , Neoplasias del Recto/patología , Adulto , Anciano , Anciano de 80 o más Años , Colectomía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Neoplasia Residual/patología , Pronóstico , Estudios Prospectivos , Neoplasias del Recto/terapia , Recto/patología , Estudios Retrospectivos , Resultado del Tratamiento
5.
Tech Coloproctol ; 21(9): 755, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28900885

RESUMEN

Unfortunately, one of the author name was wrongly published in the original publication. The complete correct name should read as follows "Beatriz Camargo Azevedo". The original article was updated.

6.
Photochem Photobiol Sci ; 13(4): 680-90, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24549049

RESUMEN

The main targets of photodynamic inactivation (PDI) are the external bacterial structures, cytoplasmic membrane and cell wall. In this work it was evaluated how the external bacterial structures influence the PDI efficiency. To reach this objective 8 bacteria with distinct external structures were selected; 4 Gram-negative bacteria (Escherichia coli, with typical Gram-negative external structures; Aeromonas salmonicida, Aeromonas hydrophila both with an S-layer and Rhodopirellula sp., with a peptidoglycan-less proteinaceous cell wall and with cytoplasm compartmentalization) and 4 Gram-positive bacteria (Staphylococcus aureus, with typical Gram-positive external structures; Truepera radiovictrix, Deinococcus geothermalis and Deinococcus radiodurans, all with thick cell walls that give them Gram-positive stains, but including a second complex multi-layered membrane and structurally analogous to that of Gram-negative bacteria). The studies were performed in the presence of 5,10,15,20-tetrakis(1-methylpyridinium-4-yl)porphyrin tetraiodide (Tetra-Py(+)-Me) at 5.0 µM with white light (40 W m(-2)). The susceptibility of each bacteria to PDI by Tetra-Py(+)-Me was dependent on bacteria external structures. Although all Gram-positive bacteria were inactivated to the detection limit (reduction of ∼8 log) after 60-180 min of irradiation, the inactivation followed distinct patterns. Among the Gram-negative bacteria, E. coli was the only species to be inactivated to the detection limit (∼8 log after 180 min). The efficiency of inactivation of the two species of Aeromonas was similar (reduction of ∼5-6 log after 270 min). Rhodopirellula was less susceptible (reduction of ∼4 log after 270 min). As previously observed, the Gram-positive bacteria are more easily inactivated than Gram-negative strains, and this is even true for T. radiovictrix, D. geothermalis and D. radiodurans, which have a complex multi-layered cell wall. The results support the theory that the outer cell structures are major bacterial targets for PDI. Moreover, the chemical composition of the external structures has a stronger effect on PDI efficiency than complexity and the number of layers of the external coating, and lipids seem to be an important target of PDI.


Asunto(s)
Antibacterianos/farmacología , Estructuras Bacterianas , Fármacos Fotosensibilizantes/farmacología , Porfirinas/farmacología , Aeromonas hydrophila/efectos de los fármacos , Aeromonas hydrophila/efectos de la radiación , Aeromonas salmonicida/efectos de los fármacos , Aeromonas salmonicida/efectos de la radiación , Antibacterianos/química , Antibacterianos/farmacocinética , Carga Bacteriana , Pared Celular , Deinococcus/efectos de los fármacos , Deinococcus/efectos de la radiación , Escherichia coli/efectos de los fármacos , Escherichia coli/efectos de la radiación , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/efectos de la radiación , Estructura Molecular , Estimulación Luminosa , Procesos Fotoquímicos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacocinética , Porfirinas/química , Porfirinas/farmacocinética , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/efectos de la radiación , Factores de Tiempo
7.
J Clin Pharm Ther ; 39(5): 564-6, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24845114

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Cannabidiol (CBD) is the main non-psychotropic component of the Cannabis sativa plant. REM sleep behaviour disorder (RBD) is a parasomnia characterized by the loss of muscle atonia during REM sleep associated with nightmares and active behaviour during dreaming. We have described the effects of CBD in RBD symptoms in patients with Parkinson's disease. CASES SUMMARY: Four patients treated with CBD had prompt and substantial reduction in the frequency of RBD-related events without side effects. WHAT IS NEW AND CONCLUSION: This case series indicates that CBD is able to control the symptoms of RBD.


Asunto(s)
Cannabidiol/uso terapéutico , Cannabis , Enfermedad de Parkinson , Fitoterapia , Trastorno de la Conducta del Sueño REM/tratamiento farmacológico , Anciano , Humanos , Masculino , Persona de Mediana Edad
8.
Artículo en Inglés | MEDLINE | ID: mdl-38704092

RESUMEN

PURPOSE: It is unclear whether preoperative serum uric acid (SUA) elevation may play a role in the development of acute kidney injury (AKI) associated with cardiac surgery (CSA-AKI). We conducted a cohort study to evaluate the influence of preoperative hyperuricemia on AKI in patients at high risk for developing SC-AKI. DESIGN: Multicenter prospective international cohort study. SETTING: Fourteen university hospitals in Spain and the United Kingdom. PARTICIPANTS: We studied 261 consecutive patients at high risk of developing CSA-AKI, according to a Cleveland score ≥ 4 points, from July to December 2017. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: AKIN criteria were used for the definition of AKI. Multivariable logistic regression models and propensity score-matched pairwise analysis were used to determine the adjusted association between preoperative hyperuricemia (≥7 mg/dL) and AKI. Elevated preoperative AUS (≥7 mg/dL) was present in 190 patients (72.8%), whereas CSA-AKI occurred in 145 patients (55.5%). In multivariable logistic regression models, hyperuricemia was not associated with a significantly increased risk of AKI (adjusted Odds Ratio [OR]: 1.58; 95% confidence interval [CI]: 0.81-3; P = .17). In propensity score-matched analysis of 140 patients, the hyperuricemia group experienced similar adjusted odds of AKI (OR 1.05, 95%CI 0.93-1.19, P = .37). CONCLUSIONS: Hyperuricemia was not associated with an increased risk of AKI in this cohort of patients undergoing cardiac surgery at high risk of developing CSA-AKI.

9.
BJOG ; 120(12): 1483-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23786390

RESUMEN

OBJECTIVE: The association between parity and type-II diabetes has been studied primarily in Western populations, and the findings have been inconsistent. Here, we examine whether parity was positively associated with incident type-II diabetes in Singaporean Chinese women. DESIGN: Prospective cohort study. SETTING: Singapore. POPULATION: A total of 25,021 Singaporean Chinese women aged 45-74 years from the Singapore Chinese Health Study who were free of cancer, heart disease, stroke, and diabetes at baseline (1993-1998). METHODS: Women were followed through 2004 for incident diabetes. Hazard ratios for type-II diabetes were computed across parity (of live births) categories and adjusted for baseline age, interview year, dialect, education, smoking, dietary pattern, physical activity, age at menarche, oral contraceptive use, menopausal status, hormone therapy use, and body mass index (BMI). MAIN OUTCOME MEASURE: Self-reported diabetes, as diagnosed by a doctor. RESULTS: Over an average of 5.7 person-years of follow-up, 1294 women were diagnosed with diabetes. Before and after multivariable adjustment there was a positive graded association between parity and type-II diabetes risk (P < 0.001). In the fully adjusted model, which included adult BMI, the risk of type-II diabetes increased by 31% (from -2 to 76%), 62% (from 22 to 116%), and 74% (from 29 to 133%) for women with one or two, three or four, and five or more live births, respectively, compared with women with no live births. Moreover, in a supplementary multivariate analysis in non-diabetic women we found a positive monotonic association between parity and glycated haemoglobin (HbA1c) (P = 0.01). CONCLUSIONS: Increased parity may be a risk factor for type-II diabetes in Chinese women. More research is needed on lifestyle and physiologic factors that may explain this association.


Asunto(s)
Diabetes Mellitus Tipo 2/etnología , Paridad/fisiología , Anciano , Pueblo Asiatico/etnología , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/epidemiología , Métodos Epidemiológicos , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Singapur/epidemiología , Fumar/epidemiología , Fumar/etnología
10.
Clin Exp Obstet Gynecol ; 40(2): 243-5, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23971250

RESUMEN

INTRODUCTION: An over-population of vaginal microorganisms causing inflammatory processes renders it difficult to properly assess the cytopathological exam that aims to screen precedent cervical lesions. On the contrary, the occurrence of the microbial flora saprophyte does not influence correct cythodiagnosis. OBJECTIVE: To assess the composition of vaginal tract aerobic microorganisms of asymptomatic women in menacme and post-menopause, and to analyze the accuracy of cytopathologic, bacterioscopic exams, and culturing of the flora. METHODS: The women were first submitted to a focused anamnestic interrogatory and then submitted to gynecological exam. A sample of the vaginal fluid was collected with a culture swab and a smear was made on two glass slides for stained bacterioscopic exam (GRAM). The collection of material was then compiled in a cytopathologic smear analysis. All women signed the free and informed consent letter and the project was approved by the Ethics Research Board of Hospital São Paulo - UNIFESP. RESULTS: Bacterioscopy and culture proved to be better than the cytopathologic exam in featuring the bacilli and cocci. The bacterioscopy provided a better detection of the presence of bacilli (p < 0.001); no statistical difference was seen between both exams with respect to the detected cocci. The beta-hemolytic Streptococcus group was of significance in post-menopausal women (p < 0.05). CONCLUSION: In this study, the bacterioscopic and culture exams of the vaginal fluid were more effective in assessing the vaginal flora and in the detection of bacilli, compared to the cytopathological exam.


Asunto(s)
Bacterias/aislamiento & purificación , Citodiagnóstico , Técnicas Microbiológicas , Vagina/microbiología , Adulto , Bacterias/clasificación , Bacterias Aerobias/clasificación , Bacterias Aerobias/aislamiento & purificación , Técnicas de Cultivo , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia , Streptococcus/clasificación , Streptococcus/aislamiento & purificación , Frotis Vaginal , Vaginosis Bacteriana/microbiología
11.
Braz J Biol ; 83: e275582, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38055505

RESUMEN

Potential breeding containers for Aedes aegypti and Aedes albopictus mosquitoes are found in different environments, these places are considered by the National Dengue Control Program in Brazil as strategic points (SP), which have favorable conditions for the development of those insects. The aim of this study is to identify potential breeding containers for A. aegypti and A. albopictus at strategic points in the city of Codó, Maranhão. This study was conducted in five districts, one in each administrative area of the city. A survey of the types and quantity of existing strategic points in each neighborhood was carried out, and surveys of these properties were carried out to inspect the potential breeding containers, with the collection of the vectors' number of immatures found at them. 125 properties were inspected of which 76.91% and 81.25% were vacant lots in the dry and rainy seasons, respectively. There was a difference between the median of the different strategic points (H = 21.96; p < 0.0001), For A. aegypti, there was no difference between the medians of number of immatures regarding the strategic points (H = 3.71; p = 0.28). The total number of immature A. albopictus was higher in vacant lots than in workshops (H = 9.41; p = 0.02, p < 0.05). 4,356 and 4,911 potential breeding containers were found in the dry and rainy seasons, respectively. Regarding the potential breeding containers, 7 (0.16%) and 47 (0.96%) were found with immature vectors, in the dry and rainy seasons, respectively. There were more positive containers in the rainy season for which there was a difference between the median of the number of mosquitoes per positive container (H = 15.66; p = 0.01), the number of immatures for the tires group was greater than Vases and Fixed groups (p < 0.05); the same result was observed in the analyses of the species in the separate form. The impressive number of potential breeding containers found in the SP in both seasons highlights the importance of developing control strategies for these vectors, with emphasis on places such as vacant lots, workshops, tire shops and junkyards, which are serving as dispersal urban sites of vectors.


Asunto(s)
Aedes , Animales , Brasil , Ciudades , Estaciones del Año , Larva
12.
Biotechnol Bioeng ; 108(8): 1766-75, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21445883

RESUMEN

Treatment of anaerobic granules with heat and two chemical treatments, contacting with 2-bromoethanesulfonate (BES) and with BES + Chloroform, were applied to suppress hydrogen-consuming microorganisms. Three mesophilic expanded granular sludge bed (EGSB) reactors-R(Heat), R(BES), and R(BES + Chlo)--were inoculated with the treated sludges and fed with synthetic sugar-based wastewater (5 g(COD) L(-1), HRT 20-12 h). Morphological integrity of granules and bacterial communities were assessed by quantitative image analysis and 16S rRNA gene based techniques, respectively. Hydrogen production in R(Heat) was under 300 mL H(2) L(-1) day(-1), with a transient peak of 1,000 mL H(2) L(-1) day(-1) after decreasing HRT. In R(BES + Chlo) hydrogen production rate did not exceed 300 mL H(2) L(-1) day(-1) and there was granule fragmentation, release of free filaments from aggregates, and decrease of granule density. In R(BES), there was an initial period with unstable hydrogen production, but a pulse of BES triggered its production rate to 700 ± 200 mL H(2) L(-1) day(-1). This strategy did not affect granules structure significantly. Bacteria branching within Clostridiaceae and Ruminococcaceae were present in this sludge. This work demonstrates that, methods applied to suppress H(2)-consuming microorganisms can cause changes in the macro- and microstructure of granular sludge, which can be incompatible with the operation of high-rate reactors.


Asunto(s)
Biodiversidad , Bacterias Grampositivas/clasificación , Bacterias Grampositivas/metabolismo , Hidrógeno/metabolismo , Aguas del Alcantarillado/microbiología , Purificación del Agua , Ácidos Alcanesulfónicos/toxicidad , Anaerobiosis , Antibacterianos/toxicidad , Cloroformo/toxicidad , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Bacterias Grampositivas/crecimiento & desarrollo , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
13.
J S Afr Vet Assoc ; 82(3): 150-4, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22332298

RESUMEN

In this study, the spinal nerves that constitute the lumbosacral plexus (plexus lumbosacrales) (LSP) and its distribution in Chinchilla lanigera were investigated. Ten chinchillas (6 males and 4 females) were used in this research. The spinal nerves that constitute the LSP were dissected and the distribution of pelvic limb nerves originating from the plexus was examined. The iliohypogastric nerve arose from L1 and L2, giving rise to the cranial and caudal nerves, and the ilioinguinal nerve arose from L3. The other branch of L3 gave rise to the genitofemoral nerve and 1 branch from L4 gave rise to the lateral cutaneous femoral nerve. The trunk formed by the union of L4-5 divided into medial (femoral nerve) and lateral branches (obturator nerve). It was found that the LSP was formed by all the ventral branches of L4 at L6 and S1 at S3. At the caudal part of the plexus, a thick branch, the ischiadic plexus, was formed by contributions from L5-6 and S1. This root gave rise to the nerve branches which were disseminated to the posterior limb (cranial and caudal gluteal nerves, caudal cutaneous femoral nerve and ischiadic nerve). The ischiadic nerve divided into the caudal cutaneous surae, lateral cutaneous surae, common fibular and tibial nerve. The pudendal nerve arose from S1-2 and the other branch of S2 and S3 formed the rectal caudal nerve. The results showed that the origins and distribution of spinal nerves that constitute the LSP of chinchillas were similar to those of a few rodents and other mammals.


Asunto(s)
Chinchilla/anatomía & histología , Miembro Posterior/inervación , Plexo Lumbosacro/anatomía & histología , Raíces Nerviosas Espinales/anatomía & histología , Animales , Femenino , Masculino
14.
Trends Biotechnol ; 39(1): 34-42, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32646618

RESUMEN

Microbial electrochemical technologies (METs) are promising for sustainable applications. Recently, electron storage during intermittent operation of electroactive biofilms (EABs) has been shown to play an important role in power output and electron efficiencies. Insights into electron storage mechanisms, and the conditions under which these occur, are essential to improve microbial electrochemical conversions and to optimize biotechnological processes. Here, we discuss the two main mechanisms for electron storage in EABs: storage in the form of reduced redox active components in the electron transport chain and in the form of polymers. We review electron storage in EABs and in other microorganisms and will discuss how the mechanisms of electron storage can be influenced.


Asunto(s)
Fuentes de Energía Bioeléctrica , Biopelículas , Electrones , Electrodos , Oxidación-Reducción
15.
Oper Dent ; 46(2): 136-142, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34107014

RESUMEN

This article presents a case report on diastema closure in anterior teeth with direct resin composite restoration. This suggested approach has been found to be efficient with regards to esthetics, marginal adaptation, and the quality of proximal contacts in diastema closure. These advantages are presented in this report.


Asunto(s)
Diastema , Diente , Resinas Compuestas , Restauración Dental Permanente , Diastema/terapia , Estética Dental , Humanos
16.
Sci Rep ; 11(1): 16350, 2021 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-34381104

RESUMEN

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.

17.
J Exp Med ; 190(12): 1825-36, 1999 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-10601357

RESUMEN

The Trypanosoma cruzi trans-sialidase can sensitize mice to become highly susceptible to T. cruzi invasion, through mechanisms that remain unknown. In pursuing this observation, we found that purified trans-sialidase induces the selective release of biologically active interleukin (IL)-6 in naive human intestinal microvascular endothelial cells (HIMECs), peripheral blood mononuclear cells (PBMCs), and bladder carcinoma cells. The trans-sialidase action was independent of its catalytic activity, as demonstrated with a genetically engineered trans-sialidase mutant, an enzymatically active polypeptide, and cocultures of PBMCs with epimastigotes and trypomastigotes. Instead, the trans-sialidase action was reproduced with a recombinant COOH-terminal tandem repeat and with synthetic peptides modeled on the tandem repeat. Most interesting, HIMECs infected with a trypomastigote population expressing trans-sialidase effectively released IL-6, but did not upon infection with the counterpart trypomastigote population expressing low trans-sialidase levels. IL-6 is a key factor in the regulation and symptom formation of infection caused by several types of viruses, such as HIV and influenza A virus. However, the function of IL-6 in protozoan and other parasitic diseases remains unclear. The unique findings presented here suggest that trans-sialidase is a major inducer of IL-6 secretion in T. cruzi infection, independently of immune cell activation. Such IL-6 secretion might underlie some features of Chagas's disease, such as pyrexia, neuroprotection, and fibrosis, and might result in the undermining of normal acquired immunity against T. cruzi.


Asunto(s)
Endotelio Vascular/metabolismo , Glicoproteínas/administración & dosificación , Glicoproteínas/metabolismo , Interleucina-6/metabolismo , Leucocitos Mononucleares/metabolismo , Neuraminidasa/administración & dosificación , Neuraminidasa/metabolismo , Secuencia de Aminoácidos , Animales , Endotelio Vascular/parasitología , Glicoproteínas/genética , Humanos , Intestinos/irrigación sanguínea , Leucocitos Mononucleares/parasitología , Ratones , Microcirculación , Datos de Secuencia Molecular , Neuraminidasa/genética , Secuencias Repetidas en Tándem , Regulación hacia Arriba/efectos de los fármacos
18.
J Food Sci ; 85(1): 132-142, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31880332

RESUMEN

Curcuma longa is a rhizome used for the extraction of curcumin, a yellow colorant that only represents 3 wt% of the dried rhizome. To increase the possibility of using the entire rhizome as a food colorant, in the present investigation, the effect of ultra-fine friction grinding (supermasscolloider) to obtain turmeric suspensions was evaluated. To achieve this goal, two distances between the grinding stones or Gap were evaluated (G of -1 and -1.5), and the obtained suspensions were characterized by infrared spectroscopy and through the determination of curcumin content, color, particle size, sedimentation index, serum cloudiness, and microstructure. The results establish that a lower G contributes to an increase in the release of curcumin in the suspension up to 21%, which is related to a greater tendency for yellow coloration, observed in the increase of the * b coordinate of color (from 61.588 to 66.497). Additionally, it was found that a lower G generates smaller particle sizes, which is related to a lower turbidity. PRACTICAL APPLICATION: This research shows that ultra-fine friction grinding (UFFG) has great potential for the development of turmeric suspensions. The results have applications in the food industry sector, because UFFG could be used to produce different types of vegetable suspensions.


Asunto(s)
Curcuma/química , Manipulación de Alimentos/métodos , Extractos Vegetales/química , Curcumina/química , Curcumina/aislamiento & purificación , Manipulación de Alimentos/instrumentación , Tamaño de la Partícula , Extractos Vegetales/aislamiento & purificación , Rizoma/química
19.
Bioresour Technol ; 278: 180-186, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30703635

RESUMEN

Co-fermentation of garden waste (GW) and food waste (FW) was assessed in a two-stage process coupling hyperthermophilic dark-fermentation and mesophilic anaerobic digestion (AD). In the first stage, biohydrogen production from individual substrates was tested at different volatile solids (VS) concentrations, using a pure culture of Caldicellulosiruptor saccharolyticus as inoculum. FW concentrations (in VS) above 2.9 g L-1 caused a lag phase of 5 days on biohydrogen production. No lag phase was observed for GW concentrations up to 25.6 g L-1. In the co-fermentation experiments, the highest hydrogen yield (46 ±â€¯1 L kg-1) was achieved for GW:FW 90:10% (w/w). In the second stage, a biomethane yield of 682 ±â€¯14 L kg-1 was obtained using the end-products of GW:FW 90:10% co-fermentation. The energy generation predictable from co-fermentation and AD of GW:FW 90:10% is 0.5 MJ kg-1 and 24.4 MJ kg-1, respectively, which represents an interesting alternative for valorisation of wastes produced locally in communities.


Asunto(s)
Clostridiales/metabolismo , Fermentación , Alimentos , Jardines , Hidrógeno/metabolismo , Metano/biosíntesis , Eliminación de Residuos/métodos , Anaerobiosis , Reactores Biológicos , Jardinería
20.
Bioresour Technol ; 99(10): 4086-95, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18006304

RESUMEN

Two anaerobic sludges previously loaded with oleate and palmitate accumulated 4570+/-257 and 5200+/-9 mgCOD-LCFAgVSS(-1), respectively. These sludges were incubated in batch assays and methane production was recorded after addition of 100-900 mg L(-1) of oleate and palmitate, respectively. The batch assays were conducted before and after allowing the depletion of the biomass-associated LCFA. The presence of biomass-associated LCFA decreased the capacity of both sludges to convert the added LCFA to methane. After the degradation of biomass-associated LCFA, the lag phases observed before the onset of methane production were significantly reduced, evidencing an increase in the tolerance of the acetotrophic methanogens to the presence of LCFA. In another experiment, three recurrent pulses were performed with a real dairy wastewater containing 3.6 gCOD L(-1), from which 53% was fat. Methane yields of 0.45+/-0.01, 0.88+/-0.02 and 1.29+/-0.08 gCOD-CH(4) gCOD(fed)(-1) were achieved in the first, second and third pulses, respectively, evidencing an increasing capacity of the sludge to convert substrate accumulated in previous additions.


Asunto(s)
Biotecnología/métodos , Ácidos Grasos/química , Metano/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Anaerobiosis , Biodegradación Ambiental , Biomasa , Reactores Biológicos , Industria Lechera , Diseño de Equipo , Ácido Oléico/análisis , Ácido Palmítico/análisis , Aguas del Alcantarillado , Agua/química
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