Recovery of ß-galactosidase produced by Kluyveromyces lactis by ion-exchange chromatography: Influence of pH and ionic strength parameters.

The use of ß-galactosidase in food products has been a major focus of the industry. Therefore, the development of efficient and inexpensive methodologies to purify it is essential. Thus, this study aimed to recover the enzyme ß-galactosidase (ß-gal) by ion-exchange chromatography in a fixed-bed column. Batch adsorption tests were performed using four types of adsorbents. The ß-gal adsorption capacity in batch mode using Streamline DEAE resin presented the best performance, with a retention capacity of 18.77 ± 0.14 U/g at pH 6.0. A 22 experimental design was applied to optimize the ß-gal recovery using an AKTA Start system, evaluating the ionic strength and the pH as process parameters. The results showed that ionic strength exerted a greater influence on fold purification (FP). The ß-gal fraction in elution using 0.1-0.4 M of NaCl showed a yield of 51.65 ± 0.17% and FP of 2.00 ± 0.43. Electrophoresis confirmed the ß-gal recovery, where an evident band with a molecular weight between 60 and 120 kDa was observed. These results point to the recovery of a stable ß-gal of K. lactis with potential industrial applications.

Investigation of the association of virulence genes and biofilm production with infection and bacterial colonization processes in multidrug-resistant Acinetobacter spp.

The aim of this study was to evaluate the phenotypic and molecular patterns of biofilm formation in infection and colonization isolates of Acinetobacter spp. from patients who were admitted in a public hospital of Recife-PE-Brazil in 2018-2019. For the biofilm phenotypic analysis, Acinetobacter spp. isolates were evaluated by the crystal violet staining method; the search of virulence genes (bap, ompA, epsA, csuE and bfmS) was performed by PCR; and the ERIC-PCR was performed for molecular typing. Amongst the 38 Acinetobacter spp. isolates, 20 were isolated from infections and 18 from colonization. The resistance profile pointed that 86.85% (33/38) of the isolates were multidrug-resistant, being three infection isolates, and two colonization isolates resistant to polymyxin B. All the isolates were able to produce biofilm and they had at least one of the investigated virulence genes on their molecular profile, but the bap gene was found in 100% of them. No clones were detected by ERIC-PCR. There was no correlation between biofilm formation and the resistance profile of the bacteria, neither to the molecular profile of the virulence genes. Thus, the ability of Acinetobacter spp. to form biofilm is probably related to the high frequency of virulence genes.

Impact of biomass burning on a metropolitan area in the Amazon during the 2015 El Niño: The enhancement of carbon monoxide and levoglucosan concentrations.

Extreme droughts associated with changes in the climate have occurred every 5 years in the Amazon during the 21st century, with the most severe being in 2015. The increase in biomass burning (BB) events that occurred during the 2015 drought had several negative socioeconomic and environmental impacts, one of which was a decrease in the air quality. This study is an investigation into the air quality in the Manaus Metropolitan Region (MMR) (central Amazon, Brazil) during the dry (September to October) and wet (April to May) seasons of 2015 and 2016. A strong El Niño event began during the wet season of 2015 and ended during the wet season of 2016. Particulate matter samples were collected in the MMR during 2015 and 2016, and analyses of the satellite-estimated total carbon monoxide (CO) column and observed levoglucosan concentrations were carried out. Levoglucosan has been shown to be significantly correlated with regional fires and is a well-established chemical tracer for the atmospheric particulates emitted by BB, and CO can be treated as a gaseous-phase tracer for BB. The number of BB events increased significantly during the El Niño period when compared to the average number during 2003-2016. Consequently, the total CO column and levoglucosan concentration values in the MMR increased by 15% and 500%, respectively, when compared to the normal conditions. These results indicate that during the period that was analyzed, the impacts of BB were exacerbated during the strong El Niño event as compared to the non-El Niño period. In this study, we provided evidence that the air quality in the MMR will degrade in the future if droughts and BB occurrences continue to increase.

Asma induzida por aspirina / Aspirin-induced asthma

Asma induzida por aspirina (AIA) é doença comum e freqüentemente subdiagnosticada. Aproximadamente 20% da população asmática é sensível à aspirina e a outros antiinflamatórios não hormonais (AINEs) e apresentam a tríade de rinossinusite com pólipos nasais, asma e hipersensibilidade à aspirina. A patogênese da AIA está associada às vias do metabolismo do ácido araquidânico: a via da lipo-oxigenase (LO) e a via da ciclo-oxigenase (CCX). Ao inibir a via da ciclo-oxigenase (CCX), a aspirina desvia os metabóhtos do ácido araquidânico para a via da LO. Isso leva à queda nos níveis de prostaglandina E2, associado ao aumento da síntese de leucotrienos cisteínicos (Cys-LT5). Os anti-leucotrienos são eficazes em bloquear a broncoconstrição provocada pela aspirina e são utilizados no tratamento desta condição. A dessensibilização tem papel importante no manejo da AIA, principalmente em pacientes que necessitam de profilaxia para doenças tromboembólicas, infarto agudo do miocárdio, e AVE. Esta revisão tem por objetivo dissertar sobre alguns aspectos atuais desta doença.

Androgênios atenuados e o tratamento do angioedema hereditário / Attenuated androgens and the treatment of hereditary angioedema

o angioedema hereditário (AEH) é uma patologia de curso crônico, que resulta da deficiência do inibidor de Cl (Cl-INH). Esta deficiência pode ser quantitativa (AEH tipo I) ou qualitativa (AEH tipo Ir). É caracterizado por edema recorrente, não pruriginoso, que pode acometer qualquer região do corpo: face,. laringe (levando a risco de morte por asfixia), extremidades, genitália, órgãos intra-abdominais (causando dor abdominal, vômitos, diarréia). O tratamento divide-se em profilático, a curto ou longo prazo, e sintomático, baseando-se sempre no impacto da doença na qualidade de vida e/ou risco de fatalidade para o paciente. As medicações utilizadas para uso crônico são os antifibrinolíticos e os androgênios atenuados. Estes últimos são geralmente mais eficazes. Esta revisão tem por objetivo abordar as principais opções terapêuticas para o tratamento do AEH, dando ênfase aos androgênios atenuados, que permanecem como drogas de primeira escolha pela sua eficácia e perfil de segurança. Para a realização deste artigo, foram consultadas publicações científicas nacionais e internacionais distribuídas em periódicos e livros-texto. As referências bibliográficas foram obtidas através da base de dados Pubmed, abrangendo o período de 1974 a 2007.

Hereditary Angioedema (AEH) is a long course pathology, which results from Cl-inhibitor (Cl-INH) deficiency. It can be a quantitative (AEH type I) or qualitative (AEH type Ir) deficiency. It is characterized by non-pruritic recurrent swellings in any part of the body: face, larynx (which could lead to death by asphyxia), extremities, genital area, abdominal organs (Ieading to abdominal pain, vomiting, diarrhea). Treatment is divided into prophylactic, short term or long term, and symptomatic, always based on the disease's impact on patient's quality of life and/or the risk of fatality. Medications used for long-term treatment are antifibrino/ytic agents and attenuated androgens. The latter usually are more effective. The aim of this review is to approach the main therapeutic options to be used in the treatment of AEH, emphasizing the attenuated androgens, which are still the first line option because of its efficacy and security.