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1.
Anal Chem ; 95(16): 6507-6513, 2023 Apr 25.
Article in English | MEDLINE | ID: mdl-37058365

ABSTRACT

The quantification of non-basic nitrogen-containing compounds (NCCs) in petroleum-derived samples has become a critical issue due to the undesirable effects of these compounds on the petroleum industry. In addition, there is a lack of analytical methods that allow the direct quantification of NCCs in these matrices. This paper provides strategies for obtaining quantitative information of NCCs in petroleum-derived samples using direct flow injection electrospray ionization (ESI) (-) Orbitrap mass spectrometry without fractionation steps. Benzocarbazole (BC) quantification was performed using the standard addition method. The method was validated, and all analytical parameters demonstrated satisfactory results in the matrix-mix. Paired Student's t-test exhibited the matrix effect (95% confidence level, p < 0.05). Limits of detection ranged from 2.94 to 14.91 µg L-1, and the limits of quantification ranged from 9.81 to 49.69 µg L-1. Intraday and interday accuracy and precision were not above 15%. Quantification of non-basic NCCs was carried out based on two approaches. In approach 1, the non-basic NCCs' total content in petroleum-derived samples was determined by the BC concentration and the total abundance correction. The method presented good performance with the average error of 21, 8.3, and 28% for crude oil, gas oil, and diesel samples, respectively. Approach 2 was based on the multiple linear regression model with regression significant at a 0.05 significance level within average relative errors of 16, 7.8, and 17% for the crude oil, gas oil, and diesel samples, respectively. Then, both approaches successfully predicted the quantification of non-basic NCCs by ESI direct flow injection.

2.
Molecules ; 27(22)2022 Nov 16.
Article in English | MEDLINE | ID: mdl-36432039

ABSTRACT

The liquid chromatography-mass spectrometry (LC-MS)-based metabolomics approach is a powerful technology for discovering novel biologically active molecules. In this study, we investigated the metabolic profiling of Orchidaceae species using LC-HRMS/MS data combined with chemometric methods and dereplication tools to discover antifungal compounds. We analyze twenty ethanolic plant extracts from Vanda and Cattleya (Orchidaceae) genera. Molecular networking and chemometric methods were used to discriminate ions that differentiate healthy and fungal-infected plant samples. Fifty-three metabolites were rapidly annotated through spectral library matching and in silico fragmentation tools. The metabolomic profiling showed a large production of polyphenols, including flavonoids, phenolic acids, chromones, stilbenoids, and tannins, which varied in relative abundance across species. Considering the presence and abundance of metabolites in both groups of samples, we can infer that these constituents are associated with biochemical responses to microbial attacks. In addition, we evaluated the metabolic dynamic through the synthesis of stilbenoids in fungal-infected plants. The tricin derivative flavonoid- and the loliolide terpenoidfound only in healthy plant samples, are promising antifungal metabolites. LC-HRMS/MS, combined with state-of-the-art tools, proved to be a rapid and reliable technique for fingerprinting medicinal plants and discovering new hits and leads.


Subject(s)
Orchidaceae , Stilbenes , Antifungal Agents/metabolism , Chromatography, Liquid/methods , Mass Spectrometry/methods , Metabolomics/methods , Plants/metabolism , Stilbenes/metabolism
3.
Arch Insect Biochem Physiol ; 110(2): e21887, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35315942

ABSTRACT

Insects overcome the action of natural protease inhibitors (PIs) due to evolutionary adaptations through endogenous proteolysis and reprogramming proteases. Insect adaptations complicate the formulation of IP-based crop protection products. However, small peptides designed based on the active site of enzymes have shown promising results that could change this scenario. GORE1 and GORE2 are designed tripeptides that reduce the survival of Anticarsia gemmatalis when ingested orally. In this article, the stability and ability of the peptides to bind trypsin-like enzymes of A. gemmatalis were evaluated by molecular dynamics (MD) simulations. The ability of the peptides to inhibit trypsin-like enzymes in vivo was compared with the SKTI protein by feeding A. gemmatalis larvae at different concentrations, followed by an inhibition persistence assay. During the MD simulation of enzyme-ligand complexes, both peptides showed a small variation of root-mean-square deviation and root-mean-square fluctuation, suggesting that these molecules reach equilibrium when forming a complex with the trypsin-like enzyme. Furthermore, both peptides form hydrogen bonds with substrate recognition sites of A. gemmatalis trypsin-like enzyme, with GORE2 having more interactions than GORE1. Larvae of A. gemmatalis exposed to the peptides and SKTI showed a similar reduction in proteolytic activity, but the persistence of inhibition of trypsin-like enzyme was longer in peptide-fed insects. Despite their size, the peptides exhibit important active and substrate binding site interactions, stability during complex formation, and steadiness effects in vivo. The results provide fundamental information for the development of mimetic molecules and help in decision-making for the selection of delivery methods for larger-scale experiments regarding similar molecules.


Subject(s)
Fabaceae , Moths , Animals , Larva , Peptides , Glycine max/metabolism , Trypsin/metabolism
4.
J Infect Dis ; 222(4): 670-680, 2020 07 23.
Article in English | MEDLINE | ID: mdl-32311029

ABSTRACT

BACKGROUND: Zika virus (ZIKV) is an emergent flavivirus initially considered a benign and self-limited exanthematic illness. In 2015, a new epidemic emerged in northeastern of Brazil with increased incidence of a previously rare clinical outcome, microcephaly, in newborns from mothers who were infected during pregnancy. Little is known about the immunopathogenesis of ZIKV-associated microcephaly. Understanding the inflammatory profile and degree of inflammation of persons affected with such condition is an important step towards development of innovative therapeutic strategies. METHODS: A case-control study compared plasma levels of several inflammatory biomarkers from newborns with ZIKV microcephaly, asymptomatic ZKV infection, or uninfected controls. Plasma biomarkers were assessed using Luminex. A series of multidimensional analysis was performed to characterize the systemic immune activation profile of the clinical groups. RESULTS: We identified an inflammatory signature associated with ZIKV microcephaly that suggested an increased inflammation. Network analysis suggested that ZIKV microcephaly is associated with imbalanced immune activation and inflammation. The cephalic perimeter was inversely proportional with the degree of inflammatory perturbation. Furthermore, a combination of plasma inflammatory biomarkers could discriminate ZIKV with microcephaly from those with ZIKV without microcephaly or uninfected neonates. CONCLUSIONS: An intense inflammatory imbalance that is proportional to the disease severity hallmarks ZIKV microcephaly.


Subject(s)
Biomarkers/blood , Inflammation/complications , Microcephaly/etiology , Zika Virus Infection/complications , Brazil , Case-Control Studies , Female , Humans , Infant, Newborn , Male , Microcephaly/diagnosis , Zika Virus/pathogenicity , Zika Virus Infection/blood , Zika Virus Infection/virology
5.
Biodegradation ; 31(1-2): 47-56, 2020 04.
Article in English | MEDLINE | ID: mdl-32193751

ABSTRACT

Two culture media were tested for the production of bacterial nanocellulose (BNC) under static culture fermentation, one containing molasses (Mol-HS), the other molasses and corn steep liquor (Mol-CSL), as a source of carbon and nitrogen, respectively. These are low-cost nutrients widely available, which provide very good BNC productivities. However, the use of these substrates generates wastewaters with high organic loads. Anaerobic digestion is one of the most promising treatments for industrial wastewaters with high organic loads since, beyond removal of the organic matter, it generates energy, in form of biogas. The wastewaters from BNC fermentation were thus evaluated for their biochemical methane potential through anaerobic digestion. For this, two wastewaters streams were collected: (i) the culture medium obtained after fermentation (WaF) and (ii) the WaF combined with BNC washing wastewaters (WaW). These two effluents-WaF and WaW-were characterized regarding their chemical oxygen demand, total nitrogen, total and volatile solids, to assess their suitability for anaerobic digestion. The biochemical methane potential of WaF and WaW from Mol-CSL wastewaters was (387 ± 14 L kg-1 VS) and (354 ± 4 L kg-1 VS), corresponding to a methanization percentage of (86.9 ± 3.1) % and (79.5 ± 0.9) %, respectively. After treatment, the chemical oxygen demand of WaF and WaW was reduced by (89.2 ± 0.4) and (88.7 ± 1.5), respectively. An exploratory test using an Upflow Anaerobic Sludge Blanket reactor for WaW treatment was also performed. The reactor was operated with a organic loading rate of [(6.5 ± 0.1) g L-1 d-1] and hydraulic retention time of 3.33 days, allowing a chemical oxygen demand removal of 58% of WaW. Results here obtained demonstrate, for the first time, the high potential of AD for the valorisation of the BNC fermentation wastewaters.


Subject(s)
Sewage , Wastewater , Anaerobiosis , Biodegradation, Environmental , Biological Oxygen Demand Analysis , Bioreactors , Methane , Waste Disposal, Fluid
6.
Int J Gynaecol Obstet ; 148 Suppl 2: 9-14, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31975394

ABSTRACT

OBJECTIVE: To identify newborns with congenital Zika infection (CZI) at a maternity hospital in Salvador, Brazil, during the 2016 microcephaly outbreak. METHODS: A prospective study enrolled microcephalic and normocephalic newborns with suspected CZI between January and December 2016. Serology (immunoglobulins IgM and IgG) and quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) for the Zika virus were performed. Demographic and clinical characteristics of newborns with and without microcephaly were compared. RESULTS: Of the 151 newborns enrolled, 32 (21.2%) were classified as microcephalic. The majority of these cases were born between January and May 2016. IgM and IgG Zika virus antibodies were detected in 5 (23.8%) and 17 (80.9%) microcephalic newborn blood samples, respectively. Six (24%) microcephalic newborns tested positive for Zika virus by RT-qPCR in urine or placenta samples. Thirteen (11.8%) normocephalic newborns also tested positive for Zika virus by PCR in urine, plasma, or placenta samples, while IgM antibodies against Zika were detected in 4 (4.2%) others. CONCLUSIONS: Identification of 17 normocephalic CZI cases, confirmed by IgM serology or RT-qPCR for Zika virus, provides evidence that CZI can present asymptomatically at birth. This finding highlights the need for prenatal and neonatal screening for Zika virus in endemic regions.


Subject(s)
Microcephaly/epidemiology , Pregnancy Complications, Infectious/etiology , Zika Virus Infection/etiology , Brazil/epidemiology , Case-Control Studies , Disease Outbreaks , Female , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Infant, Newborn , Infant, Newborn, Diseases/epidemiology , Infectious Disease Transmission, Vertical/statistics & numerical data , Male , Microcephaly/blood , Microcephaly/virology , Neonatal Screening/methods , Pregnancy , Pregnancy Complications, Infectious/blood , Pregnancy Complications, Infectious/epidemiology , Prospective Studies , Reverse Transcriptase Polymerase Chain Reaction , Zika Virus/isolation & purification , Zika Virus Infection/blood , Zika Virus Infection/epidemiology
8.
J Strength Cond Res ; 32(2): 572-577, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29120986

ABSTRACT

de Freitas, MC, Cholewa, JM, Gobbo, LA, de Oliveira, JVNS, Lira, FS, and Rossi, FE. Acute capsaicin supplementation improves 1,500-m running time-trial performance and rate of perceived exertion in physically active adults. J Strength Cond Res 32(2): 572-577, 2018-The purpose of this study was to investigate the acute effect of capsaicin supplementation on performance, rate of perceived exertion (RPE), and blood lactate concentrations during short-duration running in physically active adults. Ten physically active men (age = 23.5 ± 1.9 years, mass = 78.3 ± 12.4 kg, and height = 177.9 ± 5.9 cm) completed 2 randomized, double-blind trials: Capsaicin condition (12 mg) or a placebo condition. Forty-five minutes after supplement consumption, the participants performed a 1,500-m running time trial. Time (in seconds) was recorded. Blood lactate concentration was analyzed at rest, immediately after exercise, after 5, 10, and 30 minutes during recovery and the RPE was collected after exercise. The time was significantly (t = 3.316, p = 0.009) lower in the capsaicin (371.6 ± 40.8 seconds) compared with placebo (376.7 ± 39 seconds). Rate of perceived exertion was significantly (t = 2.753, p = 0.022) less in the capsaicin (18.0 ± 1.9) compared with the placebo (18.8 ± 1.3). Lactate increased across time for both conditions without significant differences between (p > 0.05). In summary, acute capsaicin supplementation improves middle distance running (1,500 m) performance and reduced RPE in physically active adults.


Subject(s)
Capsaicin/therapeutic use , Dietary Supplements , Physical Exertion/drug effects , Running/physiology , Adult , Cross-Over Studies , Double-Blind Method , Exercise Test , Heart Rate/drug effects , Humans , Lactic Acid/blood , Male , Perception , Rest/physiology , Young Adult
9.
Zootaxa ; 4098(3): 560-70, 2016 Apr 07.
Article in English | MEDLINE | ID: mdl-27394601

ABSTRACT

The description of a new species, Cyphoderus caetetus sp. nov., led to comparisons among Paronellidae (Cyphoderinae and Paronellinae), which showed that the chaetotaxy of the first abdominal segment is very similar in Cyphoderus, Troglobius (Cyphoderinae) and Trogolaphysa (Paronellini), and much reduced in relation to that seen in Lepidonella (Paronellinae, Bromacanthini), Pseudosinella and Seira (Entomobryidae). This feature, along with the presence of pseudopores behind the posterior row of setae on the fourth abdominal segment as seen in Troglopedetes, Trogolaphysa and Cyphoderinae (absent in Lepidonella and Entomobryidae), suggests that Cyphoderinae is more closely related to tribe Paronellini than Paronellini is to Bromacanthini and Entomobryidae, and that the subfamily Paronellinae is paraphyletic if Cyphoderinae is excluded. We propose including Cyphoderini as the apical group in Paronellinae together with Paronellini (Trogolaphysa and Troglopedetes).


Subject(s)
Arthropods/classification , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Arthropods/anatomy & histology , Arthropods/growth & development , Body Size , Ecosystem , Male , Organ Size
10.
Bioresour Technol ; 190: 251-6, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25958149

ABSTRACT

Potential biohythane production from Sargassum sp. was evaluated in a two stage process. In the first stage, hydrogen dark fermentation was performed by Caldicellulosiruptor saccharolyticus. Sargassum sp. concentrations (VS) of 2.5, 4.9 and 7.4gL(-1) and initial inoculum concentrations (CDW) of 0.04 and 0.09gL(-1) of C. saccharolyticus were used in substrate/inoculum ratios ranging from 28 to 123. The end products from hydrogen production process were subsequently used for biogas production. The highest hydrogen and methane production yields, 91.3±3.3Lkg(-1) and 541±10Lkg(-1), respectively, were achieved with 2.5gL(-1) of Sargassum sp. (VS) and 0.09gL(-1)of inoculum (CDW). The biogas produced contained 14-20% of hydrogen. Potential energy production from Sargassum sp. in two stage process was estimated in 242GJha(-1)yr(-1). A maximum energy supply of 600EJyr(-1) could be obtained from the ocean potential area for macroalgae production.


Subject(s)
Biofuels/microbiology , Hydrogen/metabolism , Methane/metabolism , Sargassum/physiology , Seawater/microbiology , Anaerobiosis/physiology , Aquatic Organisms/metabolism , Batch Cell Culture Techniques/methods , Bioreactors/microbiology , Cell Proliferation/physiology , Fermentation , Hydrogen/isolation & purification , Light , Methane/isolation & purification , Sargassum/classification , Species Specificity , Water Microbiology
11.
J Strength Cond Res ; 27(8): 2304-8, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23207883

ABSTRACT

This study examined whether passive static stretching reduces the maximum muscle strength achieved by different body segments in untrained and resistance-trained subjects. Twenty adult men were assigned to 1 of the following groups: untrained (UT, N = 9) and resistance-trained (RT, N = 11) groups. The subjects performed six 1 repetition maximum (1RM) load tests of the following exercises: horizontal bench press, lat pull-downs, bicep curls, and 45° leg press. The results achieved in the last two 1RM tests were used for statistical analyses. A passive static stretching program was incorporated before the sixth 1RM test. The body fat content was significantly higher in the UT group compared with the RT group (p < 0.0001). Moreover, the RT group showed significantly higher proportion of lean body mass compared with the UT group (p < 0.0001). Maximum muscle strength on all 4 exercises was significantly reduced in both groups after stretching (p < 0.01). Furthermore, the magnitude of muscle strength reduction was similar for the UT and the RT groups. The exception was for barbell curls, in which the muscle strength depression was significantly higher in the UT group compared with the RT group (p < 0.0001). In conclusion, the passive static stretching program was detrimental to upper- and lower-body maximal muscle strength performance in several body segments. The negative effects of stretching were similar for subjects participating in resistance training regimens.


Subject(s)
Muscle Strength/physiology , Muscle Stretching Exercises/adverse effects , Muscle Weakness/etiology , Muscle, Skeletal/physiopathology , Physical Fitness/physiology , Resistance Training , Adult , Body Composition , Humans , Lower Extremity/physiopathology , Male , Muscle Weakness/prevention & control , Torso/physiopathology , Upper Extremity/physiopathology , Young Adult
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