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1.
Bull Entomol Res ; 114(1): 124-133, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38268108

RESUMO

Neotropical cyclocephaline beetles, a diverse group of flower-loving insects, significantly impact natural and agricultural ecosystems. In particular, the genus Cyclocephala, with over 350 species, displays polymorphism and cryptic complexes. Lacking a comprehensive DNA barcoding framework, accessible tools for species differentiation are needed for research in taxonomy, ecology, and crop management. Moreover, cuticular hydrocarbons are believed to be involved in sexual recognition mechanisms in these beetles. In the present study we examined the cuticular chemical profiles of six species from the genus Cyclocephala and two populations of Erioscelis emarginata and assessed their efficiency in population, species, and sex differentiation. Overall we identified 74 compounds in cuticular extracts of the selected taxa. Linear alkanes and unsaturated hydrocarbons were prominent, with ten compounds between them explaining 85.6% of species dissimilarity. Although the cuticular chemical profiles efficiently differentiated all investigated taxa, only C. ohausiana showed significant cuticular profile differences between sexes. Our analysis also revealed two E. emarginata clades within a larger group of 'Cyclocephala' species, but they were not aligned with the two studied populations. Our research underscores the significance of cuticular lipid profiles in distinguishing selected cyclocephaline beetle species and contemplates their potential impact as contact pheromones on sexual segregation and speciation.


Assuntos
Besouros , Animais , Besouros/genética , Ecossistema , Hidrocarbonetos , Feromônios/química , Lipídeos/análise
2.
Eur J Prosthodont Restor Dent ; 31(3): 214-223, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36515423

RESUMO

OBJECTIVE: The antimicrobial effect of prosthetic materials treated with chitosan was systematically reviewed. METHODS: The searches were carried out on PubMed/Medline, Scopus, ISI Web of Science, LILACS, Embase, and Open Grey with searches performed in March 2022. Selection of in vitro studies, data extraction and risk of bias analysis were performed following the PRISMA guidelines and registered at the Open Science Framework. The evaluated prosthetic materials corresponded to PMMA and tissue conditioner, treated with chitosan. RESULTS: After evaluating the eligibility criteria, 11 articles were included for the qualitative synthesis. The evaluated prosthetic materials corresponded to PMMA (n=8) and tissue conditioner (n=3). All studies performed the incorporation of chitosan in the tissue conditioner (n=3). Regarding PMMA, the use of chitosan as a denture cleanser was the most used (n=3), followed by incorporation (n=2), multilayers coating onto PMMA (n=2) and denture adhesive for PMMA (n=1). Chitosan has antimicrobial activity and is effective in the treatment of prosthetic materials in most studies, but it depends on some factors, such as the treatment method, the type and characteristics of the chitosan, the microorganism evaluated, and its form of organization. CONCLUSION: Chitosan showed highly antimicrobial activity and was effective when used in prosthetic materials.


Assuntos
Anti-Infecciosos , Quitosana , Quitosana/farmacologia , Polimetil Metacrilato , Anti-Infecciosos/farmacologia , Teste de Materiais
3.
Biochem Soc Trans ; 50(6): 1737-1751, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36383062

RESUMO

Pyrethroids (PY) are synthetic pesticides used in many applications ranging from large-scale agriculture to household maintenance. Their classical mechanisms of action are associated with binding to the sodium channel of insect neurons, disrupting its inactivation, ensuring their use as insecticides. However, PY can also lead to toxicity in vertebrates, including humans. In most toxicological studies, the impact of PY on heart function is neglected. Acute exposure to a high dose of PY causes enhancement of the late sodium current (INaL), which impairs the action potential waveform and can cause severe cardiac arrhythmias. Moreover, long-term, low-dose exposure to PY displays oxidative stress in the heart, which could induce tissue remodeling and impairment. Isolated and preliminary evidence supports that, for acute exposure to PY, an antiarrhythmic therapy with ranolazine (an INaL blocker), can be a promising therapeutic approach. Besides, heart tissue remodeling associated with low doses and long-term exposure to PY seems to benefit from antioxidant therapy. Despite significant leaps in understanding the mechanical details of PY intoxication, currently, few studies are focusing on the heart. In this review, we present what is known and what are the gaps in the field of cardiotoxicity induced by PY.


Assuntos
Cardiotoxicidade , Piretrinas , Animais , Humanos , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/metabolismo , Piretrinas/toxicidade , Ranolazina , Bloqueadores dos Canais de Sódio/farmacologia , Canais de Sódio/metabolismo
4.
Int J Mol Sci ; 23(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36361818

RESUMO

The inflammasome complex is a key part of chronic diseases and acute infections, being responsible for cytokine release and cell death mechanism regulation. The SARS-CoV-2 infection is characterized by a dysregulated cytokine release. In this context, the inflammasome complex analysis within SARS-CoV-2 infection may prove beneficial to understand the disease's mechanisms. Post-mortem minimally invasive autopsies were performed in patients who died from COVID-19 (n = 24), and lung samples were compared to a patient control group (n = 11) and an Influenza A virus H1N1 subtype group from the 2009 pandemics (n = 10). Histological analysis was performed using hematoxylin-eosin staining. Immunohistochemical (IHC) staining was performed using monoclonal antibodies against targets: ACE2, TLR4, NF-κB, NLRP-3 (or NALP), IL-1ß, IL-18, ASC, CASP1, CASP9, GSDMD, NOX4, TNF-α. Data obtained from digital analysis underwent appropriate statistical tests. IHC analysis showed biomarkers that indicate inflammasome activation (ACE2; NF-κB; NOX4; ASC) were significantly increased in the COVID-19 group (p < 0.05 for all) and biomarkers that indicate cell pyroptosis and inflammasome derived cytokines such as IL-18 (p < 0.005) and CASP1 were greatly increased (p < 0.0001) even when compared to the H1N1 group. We propose that the SARS-CoV-2 pathogenesis is connected to the inflammasome complex activation. Further studies are still warranted to elucidate the pathophysiology of the disease.


Assuntos
COVID-19 , Vírus da Influenza A Subtipo H1N1 , Humanos , Inflamassomos/metabolismo , SARS-CoV-2 , Interleucina-18 , NF-kappa B/metabolismo , Enzima de Conversão de Angiotensina 2 , Autopsia , Vírus da Influenza A Subtipo H1N1/metabolismo , Caspase 1/metabolismo , Pulmão/metabolismo , Citocinas/metabolismo , Biópsia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
5.
J Org Chem ; 86(7): 5245-5254, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33724842

RESUMO

The uncommon jasmone derivatives dehydrojasmone, isojasmol, and isojasmyl acetate, floral scent compounds from night-blooming Araceae, were synthesized in a scalable synthesis employing conjugate addition with a selenoacetal as the key step. The stereoselective strategy with subsequent enzymatic kinetic resolution allowed determining the absolute configuration of the natural compounds by GC on a chiral phase. The homoterpene (E)-4,8-dimethyl-1,3,7-nonatrien-5-yl acetate, another uncommon scent compound, was obtained by α-regioselective aldehyde prenylation. The biological activities of dehydrojasmone and isojasmol were investigated in field assays, showing that these unique volatiles are able to selectively attract specific cyclocephaline scarab beetle pollinators.


Assuntos
Araceae , Compostos Orgânicos Voláteis , Flores , Odorantes , Feromônios , Polinização
6.
Naturwissenschaften ; 108(3): 21, 2021 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-33934251

RESUMO

Olfactory signaling is key to the reproductive biology of entomophilous palms. Both pollinating and specialized herbivorous insects are attracted to fragrance-emitting palm inflorescences that function as reliable food sources, as well as mating and oviposition sites. In the present study, we characterized the floral scent chemistry of the acuri palm (Attalea phalerata), assessing its role in the attraction of flower-visiting insects associated with this species over its natural distribution range. We sampled insects from staminate inflorescences of A. phalerata (n = 6) at four different sites in the Brazilian Atlantic Forest and Cerrado, and Colombian Amazon basin. Dynamic headspace scent samples of both pistillate and staminate inflorescences of A. phalerata (n = 3♀, 3♂) were collected and analyzed by gas chromatography-mass spectrometry. Methyl acetate, a rare floral scent compound, was identified as the almost exclusive constituent (> 99.8% relative percentage) in all the samples. Flight-interception traps baited with methyl acetate, installed in one of the sites in the Brazilian Cerrado, were attractive to beetles associated with inflorescences of A. phalerata across all four sampling sites (9 spp. in total), including the putative main pollinators (Mystrops spp., Nitidulidae; Andranthobius spp., Curculionidae) and various palm borers (Paratenthras martinsi, Cerambycidae; Parisoschoenus sp.1 and Belopoeus sp.1; Curculionidae). Methyl acetate is highly volatile and we hypothesize its efficacy relies on profuse emission by the inflorescences of A. phalerata, as specialized pollinating insects respond to high concentrations of the attractant, perhaps before odor plumes rapidly disperse. Such a strategy could prove particularly effective in dense populations of A. phalerata.


Assuntos
Acetatos/farmacologia , Arecaceae/química , Besouros/efeitos dos fármacos , Flores/química , Animais , Brasil , Besouros/fisiologia , Cromatografia Gasosa-Espectrometria de Massas , Feromônios/química , Polinização
7.
Transpl Infect Dis ; 22(1): e13213, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31724282

RESUMO

BACKGROUND: BK polyomavirus-associated nephropathy (PyVAN) is an important complication after kidney transplantation. Prevalence ranges from 1% to 10%, and graft loss occurs in approximately 50% of the cases. There is no effective treatment, so early viral detection with immunosuppression tapering is the current strategy to prevent PyVAN. AIMS: To verify the frequency of PyVAN in a single center and evaluate the response to immunosuppressive adjustments through graft survival analysis. METHODS: Retrospective evaluation of a cohort of kidney transplant recipients with biopsy-proven PyVAN, compared with no-PyVAN patients regarding clinical aspects, immunosuppression, and graft survival over at least 2 years. RESULTS: There were 1404 kidney transplants analyzed in the study period, 58 with biopsy-proven PyVAN. Cumulative incidence was 4.1%. Median time from transplantation to PyVAN diagnosis was 6 (1-41) months. PyVAN was associated with recipient male gender (P = .041) and deceased donation (P = .005). Graft survival was inferior for PyVAN compared to no-PyVAN patients, 81.8% vs 75.2%, P = .019. Thirteen (22.4%) PyVAN patients lost their grafts, nine (15.5%) losses attributed to BKPyV infection. Three patients with BKPyV-associated graft losses were submitted to a successful second kidney transplant, with no evidence of viral replication during follow-up. CONCLUSION: PyVAN still is an important cause of kidney graft failure. Even though implementing active vigilance and immunosuppressive adjustment, this real-life single-center study demonstrated inferior graft survival in PyVAN patients compared to non-PyVAN.


Assuntos
Rejeição de Enxerto/virologia , Nefropatias/virologia , Transplante de Rim/efeitos adversos , Infecções por Polyomavirus/etiologia , Infecções Tumorais por Vírus/etiologia , Adulto , Vírus BK/patogenicidade , Feminino , Sobrevivência de Enxerto , Humanos , Terapia de Imunossupressão/efeitos adversos , Rim/patologia , Rim/virologia , Nefropatias/prevenção & controle , Masculino , Pessoa de Meia-Idade , Infecções por Polyomavirus/complicações , Estudos Retrospectivos , Fatores Sexuais , Transplante Homólogo/efeitos adversos , Infecções Tumorais por Vírus/complicações , Viremia , Adulto Jovem
8.
Epilepsy Behav ; 111: 107315, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32694039

RESUMO

PURPOSE: Patients with a first unprovoked epileptic seizure are often seen in emergency services. Electroencephalography (EEG) is indicated for diagnosing epilepsy, but the optimal time to perform this test has not been defined. This study aimed to determine the time interval following a seizure within which EEG has the greatest diagnostic yield. METHODS: We conducted a retrospective study of all adult patients with a first unprovoked seizure who had undergone emergency EEG (July 2014-December 2019). Data collection included demographics, seizure type, time interval to EEG study, EEG pattern identified, and the prescription after emergency assessment. An optimal cut-off point for time to EEG was obtained, and an adjusted regression model was performed to establish associations with the presence of epileptiform abnormalities. RESULTS: A total of 170 patients were included (mean age: 50.7 years, 40.6% women). Epileptiform discharges were identified in 34.1% of recordings, nonepileptiform abnormalities in 46.5%, and normal findings in 19.4%. A lower latency from seizure to EEG was associated with a higher probability of finding epileptiform discharges (median: 12.7 in the epileptiform EEGs vs. 20 h in the nonepileptiform EEGs, p < 0.001). The time interval associated with the highest probability of detecting an epileptiform EEG pattern was within the first 16 h after seizure onset: 52.1% of recordings performed before the 16-h cut-off showed these abnormal patterns compared with 20.2% performed after (p < 0.001). These findings were not related to the presence of an epileptogenic lesion in neuroimaging or to other clinical variables. The finding of epileptiform abnormalities was followed by a greater prescription of antiseizure drugs (96.4% vs. 66% in nonepileptiform patterns, p < 0.001). CONCLUSION: The diagnostic yield of EEG following a first unprovoked epileptic seizure is highest when this test is performed within the first 16 h after onset of the event.


Assuntos
Eletroencefalografia/métodos , Serviços Médicos de Emergência/métodos , Convulsões/diagnóstico por imagem , Convulsões/fisiopatologia , Tempo para o Tratamento , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem/métodos , Estudos Retrospectivos , Adulto Jovem
9.
J Chem Ecol ; 46(10): 1010-1015, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32984924

RESUMO

Defensive secretions of millipedes are remarkable for containing toxic quinones known to efficiently repell hematophagous arthropods. Here we show that Endangered blonde capuchin monkeys make use of such secretions. We (i) describe the anointing behavior performed by the monkeys (ii) identify the millipede species used in the process (iii) describe the volatile chemical composition of its secretion. The blonde capuchin monkeys selectively searched for millipedes hidden under the ground. We observed three bouts of anointing behavior, performed by 13 individuals of all age classes (from adults to independent infants), both solitarily (1 event) and socially (10 events). The only millipede species used by the monkeys is an undescribed species of the genus Poecilocricus (Spirobolida, Rhinocricidae). The volatile chemical composition of the secretions was predominantly comprised of a mixture of benzoquinones and hydroquinones. The social nature of the behavior and time of the observations (mosquito season), suggest that social bonding and mosquito avoidance is linked to the anointing behavior of the monkeys.


Assuntos
Artrópodes/metabolismo , Comportamento Animal/efeitos dos fármacos , Benzoquinonas/farmacologia , Cebus/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Hidroquinonas/farmacologia , Animais , Artrópodes/química , Benzoquinonas/isolamento & purificação , Hidroquinonas/isolamento & purificação , Comportamento Social
10.
Int J Qual Health Care ; 32(5): 313-318, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32232330

RESUMO

OBJECTIVE: To know what hospital managers and safety leaders in Ibero-American countries are doing to respond effectively to the occurrence of adverse events (AEs) with serious consequences for patients. DESIGN: Cross-sectional international study. SETTING: Public and private hospitals in Ibero-American countries (Argentina, Brazil, Chile, Colombia, Mexico, Peru, Portugal and Spain). PARTICIPANTS: A convenience sample of hospital managers and safety leaders from eight Ibero-American countries. A minimum of 25 managers/leaders from each country were surveyed. INTERVENTIONS: A selection of 37 actions for the effective management of AEs was explored. These were related to the safety culture, existence of a crisis plan, communication and transparency processes with the patients and their families, attention to second victims and institutional communication. MAIN OUTCOME MEASURE: Degree of implementation of the actions studied. RESULTS: A total of 190 managers/leaders from 126 (66.3%) public hospitals and 64 (33.7%) private hospitals participated. Reporting systems, in-depth analysis of incidents and non-punitive approaches were the most implemented interventions, while patient information and care for second victims after an AE were the least frequent interventions. CONCLUSIONS: The majority of these hospitals have not protocolized how to act after an AE. For this reason, it is urgent to develop and apply a strategic action plan to respond to this imperative safety challenge. This is the first study to identify areas of work and future research questions in Ibero-American countries.


Assuntos
Administração Hospitalar/métodos , Erros Médicos/efeitos adversos , Erros Médicos/prevenção & controle , Estudos Transversais , Família/psicologia , Hospitais , Humanos , América Latina , Segurança do Paciente , Recursos Humanos em Hospital/psicologia , Portugal , Gestão da Segurança , Espanha , Inquéritos e Questionários
11.
J Therm Biol ; 92: 102657, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32888561

RESUMO

The increases in CO2 concentrations and, consequently, temperature due to climate change are predicted to intensify. Understanding the physiological responses of Pyrrhulina aff. brevis to the climatic scenarios proposed by the IPCC (2014) for the next 100 years is of fundamental importance to determine its susceptibility. Thus, the present study aimed to evaluate the effects of the predicted climatic scenarios for the year 2100 on the metabolic adjustments of P. aff. brevis . Specifically, the rate of oxygen uptake, electron transport system capacity, glycogen and lactate content and the role of Na+K+-ATPases and H+-ATPase were evaluated. P. aff. brevis individuals were exposed for 15 days to the simulated climatic scenarios in climate scenario rooms, where temperature and CO2 in the air were controlled. Two rooms were used to simulate the climatic scenarios predicted by the IPCC (2014): moderate (RCP 6; 2.5 °C and 400 µatm CO2 above current levels) and extreme (RCP 8.5; 4.5 °C and 900 µatm CO2 above current levels), in addition to the "control room" that represents the current scenario. There was an increase in the metabolic rate (MO2) in the animals acclimated to the climate change scenarios (RCP 6 and RCP 8.5) compared to the current scenario. These responses showed a typical effect of temperature on energy demand in relation to the increase in temperature and CO2. Our data showed an increase in O2 consumption (MO2), lactate levels and H+-ATPase activity of the animals acclimated to the moderate and extreme climate change scenarios. Such adjustments presented a clear metabolic imbalance, an alteration that may imply challenges for survival, growth, distribution and reproduction in the face of the expected environmental changes for the year 2100.


Assuntos
Aclimatação , Caraciformes/fisiologia , Mudança Climática , Animais , Metabolismo Basal , Brasil , Dióxido de Carbono/metabolismo , Oxigênio/metabolismo , Consumo de Oxigênio
12.
Br Poult Sci ; 61(4): 454-464, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32233666

RESUMO

1. Changes in feather length and weight and daily losses of down, contour feathers, remiges and retrices were studied in two commercial broiler strains to determine feather growth and moult in broilers up to 112 d of age. 2. Ten pens of 20 chicks for each sex x strain were fed adequate amounts of dietary protein in a four-phase feeding programme. Ten birds were sampled per genotype at 14, 28, 42, 56, 70, 84, 98 and 112 d. Feather loss was determined for individual birds caged within a nylon net. 3. All feathers were dry-plucked from each of seven tracts, with representative feathers from the capital-cervical, dorsopelvic and interscapular, pectoral and femoral tracts being randomly selected. Three rectrices of the dorsocaudal tract and three primaries and secondaries of the humeral-alar tract of the right wing were evaluated. 4. The length of the selected feathers was measured, and the feathers from each tract and from the whole bird were weighed. 5. A wide range of rates of maturing (0.0250-0.0907/d) and mature weights (9.62-52.9 g) were evident between sampled tracts. 6. Feather weight failed to predict some moults which were detected by the measurement of feather losses. From the weight data, moulting was evident only in the humeral-alar and dorsocaudal tracts, whereas, when daily losses were measured, contour feathers accounted for over 0.7 proportion of feather losses. Logistic equations adequately described the cumulative losses of down, contour feathers and remiges. 7. Feather loss needs to be considered when feather growth is determined from feather weight at different ages. 8. The rate of maturing (B) of feathers was numerically higher in Ross males and females than in the Cobb strain. In females, B was higher than in males (0.0483 vs. 0335/d) but the mature weight was lower (162 vs. 230 g).


Assuntos
Plumas , Muda , Animais , Peso Corporal , Galinhas , Proteínas Alimentares , Feminino , Masculino
13.
J Chem Ecol ; 45(2): 204-213, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30229355

RESUMO

Nocturnal flowering plants often release strong scents to attract their pollinators. Among night active flower visitors are cyclocephaline scarab beetles, which have been demonstrated to respond to uncommon volatile organic compounds released in high amounts by their host plants. In Araceae, the molecular structure of several such compounds is yet to be unveiled. We investigated headspace floral scent samples of Philodendron squamiferum, Thaumatophyllum mello-baretoanum, and Xanthosoma hylaeae by a variety of approaches, leading to the identification of novel compounds. Dehydrojasmone, (Z)-4-methylene-5-(pent-2-en-1-yl)cyclopent-2-en-1-one (1), (Z)-3-methylene-2-(pent-2-en-1-yl)cyclopentyl acetate (isojasmyl acetate, 3), and (E)-4,8-dimethylnona-1,3,7-trien-5-yl acetate (4) had not been previously reported, while full analytical data of the recently described (Z)-3-methylene-2-(pent-2-en-1-yl)cyclopentan-1-ol (isojasmol, 2) are presented here. All these compounds are derived from more common precursors, (Z)-jasmone and (E)-4,8-dimethyl-1,3,7-nonatriene, likely through biosynthetic "post-processing".


Assuntos
Araceae/química , Besouros/fisiologia , Compostos Orgânicos Voláteis/química , Animais , Araceae/metabolismo , Ciclopentanos/química , Flores/química , Flores/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Oxilipinas/química , Polinização/efeitos dos fármacos , Compostos Orgânicos Voláteis/farmacologia
14.
J Chem Ecol ; 45(2): 214-215, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30334116

RESUMO

The original version of this article unfortunately contained a mistake. The description of subheadings of Figs. 4c and d have to be interchanged.

16.
Pharmazie ; 74(12): 715-720, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31907109

RESUMO

A copper(II) complex-loaded castor oil-based nanostructured lipid carrier was evaluated to enhance the poor water solubility of antimicrobial compounds, improving their biological properties and antimicrobial activity against Mycobacterium tuberculosis. Nanostructured lipid carriers were composed of the castor oil, polyoxyethylene 40 stearate and caprylic/capric triglyceride, poloxamer 407, cetyltrimethylammonium bromide and three different copper(II) complexes. The systems were ultrasonicated at an amplitude of 8% for 20 min and an ice bath was used throughout the procedure. The blank nanostructured lipid carrier (F5) and nanostructured lipid carriers loaded with copper(II) complex 1, 2 and 3 (F5.1, F5.2 and F5.3, respectively) for 45 days presented values of mean diameter, poly dispersity index and zeta potential ranging from 186 to 199 nm, 0.14 to 0.2 and 24 to 30 mV, respectively. Atomic force microscopy indicated that the nanostructured lipid carriers were distributed at the nanoscale, corroborating the mean diameter data. Differential scanning calorimetry determined the melting points of the constituents of the nanostructured lipid carriers. The antimicrobial activity of copper(II) complexloaded F5 against M. tuberculosis H37Rv showed better anti-tuberculosis activity than the free complexes. In vivo biological assays of complex-loaded F5 demonstrated reduced toxicity. Our results suggest that nanostructured lipid carriers could be a potential nanotechnological strategy to optimise tuberculosis treatment.


Assuntos
Antibacterianos/farmacologia , Óleo de Rícino/farmacologia , Cobre/farmacologia , Portadores de Fármacos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Bioensaio , Lipídeos , Testes de Sensibilidade Microbiana , Nanoestruturas , Tamanho da Partícula
17.
Cardiovasc Diabetol ; 17(1): 15, 2018 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-29343259

RESUMO

BACKGROUND: Increased reactive oxygen species (ROS) generation in diabetes mellitus (DM) is an important mechanism leading to diabetic cardiomyopathy. Apocynin, a drug isolated from the herb Picrorhiza kurroa, is considered an antioxidant agent by inhibiting NADPH oxidase activity and improving ROS scavenging. This study analyzed the influence of apocynin on cardiac remodeling in diabetic rats. METHODS: Six-month-old male Wistar rats were assigned into 4 groups: control (CTL, n = 15), control + apocynin (CTL + APO, n = 20), diabetes (DM, n = 20), and diabetes + apocynin (DM + APO, n = 20). DM was induced by streptozotocin. Seven days later, apocynin (16 mg/kg/day) or vehicle was initiated and maintained for 8 weeks. Left ventricular (LV) histological sections were used to analyze interstitial collagen fraction. NADPH oxidase activity was evaluated in LV samples. Comparisons between groups were performed by ANOVA for a 2 × 2 factorial design followed by the Bonferroni post hoc test. RESULTS: Body weight (BW) was lower and glycemia higher in diabetic animals. Echocardiogram showed increased left atrial diameter, LV diastolic diameter, and LV mass indexed by BW in both diabetic groups; apocynin did not affect these indices. LV systolic function was impaired in DM groups and unchanged by apocynin. Isovolumic relaxation time was increased in DM groups; transmitral E/A ratio was higher in DM + APO compared to DM. Myocardial functional evaluation through papillary muscle preparations showed impaired contractile and relaxation function in both DM groups at baseline conditions. After positive inotropic stimulation, developed tension (DT) was lower in DM than CTL. In DM + APO, DT had values between those in DM and CTL + APO and did not significantly differ from either group. Myocardial interstitial collagen fraction was higher in DM than CTL and did not differ between DM + APO and CTL + APO. Serum activity of antioxidant enzymes glutathione peroxidase, superoxide dismutase (SOD), and catalase was lower in DM than CTL; apocynin restored catalase and SOD levels in DM + APO. Myocardial NADPH oxidase activity did not differ between groups. CONCLUSION: Apocynin restores serum antioxidant enzyme activity despite unchanged myocardial NADPH oxidase activity in diabetic rats.


Assuntos
Acetofenonas/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Cardiomiopatias Diabéticas/prevenção & controle , Sequestradores de Radicais Livres/farmacologia , Ventrículos do Coração/efeitos dos fármacos , Estreptozocina , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos , Animais , Catalase/sangue , Colágeno , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/complicações , Cardiomiopatias Diabéticas/sangue , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/fisiopatologia , Glutationa Peroxidase/sangue , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Masculino , NADPH Oxidases/metabolismo , Ratos Wistar , Superóxido Dismutase/sangue
18.
J Exp Biol ; 221(Pt 2)2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-29212844

RESUMO

The Amazonian cichlid Astronotus ocellatus is highly tolerant to hypoxia, and is known to reduce its metabolic rate by reducing the activity of energetically expensive metabolic processes when oxygen is lacking in its environment. Our objectives were to determine how protein metabolism is regulated in A. ocellatus during hypoxia. Fish were exposed to a stepwise decrease in air saturation (100%, 20%, 10% and 5%) for 2 h at each level, and sampled throughout the experiment. A flooding dose technique using a stable isotope allowed us to observe an overall decrease in protein synthesis during hypoxia in liver, muscle, gill and heart. We estimate that this decrease in rates of protein synthesis accounts for a 20 to 36% decrease in metabolic rate, which would enable oscars to maintain stable levels of ATP and prolong survival. It was also determined for the first time in fish that a decrease in protein synthesis during hypoxia is likely controlled by signaling molecules (4EBP1 and eIF2-α), and not simply due to a lack of ATP. We could not detect any effects of hypoxia on protein degradation as the levels of NH4 excretion, indicators of the ubiquitin proteasome pathway, and enzymatic activities of lysosomal and non-lysosomal proteolytic enzymes were maintained throughout the experiment.


Assuntos
Ciclídeos/genética , Proteínas de Peixes/genética , Biossíntese de Proteínas , Transdução de Sinais , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Ciclídeos/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Jejum , Proteínas de Peixes/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo
19.
J Hum Nutr Diet ; 31(2): 266-275, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28791776

RESUMO

BACKGROUND: Predictive equations are the main clinical tools for determining resting energy expenditure (REE). However, their adequate use in overweight and obese individuals is unclear. Thus, we investigated the best predictive equations for estimating REE in overweight and obese women with polycystic ovary syndrome (PCOS). METHODS: Eleven analyses were performed with prediction equations (pREE) based on anthropometric parameters in 30 overweight or obese women with PCOS without other chronic diseases. The measured REE (mREE) was calculated by indirect calorimetry. The validity of the equations was investigated by comparison, accuracy and agreement tests between pREE and mREE at both the individual and group level. RESULTS: Four analyses were similar to those of mREE, and smallest mean differences were observed for the World Health Organization/Food and Agriculture Organization of the United Nations/United Nations University (WHO/FAO/UNU) considering weight (W) [0.07 (1.13) MJ (16 [270] kcal)]. Individual accuracy was greater than 50% for Harris and Benedict, Müller and Lazzer equations. The percentage of REE underestimation ranged between 16.7% and 73.3%, whereas higher rates of overestimation were observed in the De Luis (66.7%) and Ireton-Jones (43.3%) equations. Mean bias at the group level was lowest in the WHO/FAO/UNU W and WHO/FAO/UNU considering weight and height (WH), Müller and Lazzer equations (-2.8 to 0.5). The WHO/FAO/UNU W and WHO/FAO/UNU WH formulas were optimal in individual agreement (33.3%). CONCLUSIONS: FAO/WHO/UNU W equations may estimate the REE in overweight and obese women with PCOS. However, the low individual accuracy and agreement in relation to mREE suggest caution regarding when to use the formula to perform an individual nutritional plan.


Assuntos
Metabolismo Basal , Índice de Massa Corporal , Conceitos Matemáticos , Modelos Biológicos , Obesidade/metabolismo , Síndrome do Ovário Policístico/metabolismo , Descanso , Adolescente , Adulto , Antropometria , Calorimetria Indireta , Feminino , Humanos , Pessoa de Meia-Idade , Modelos Teóricos , Obesidade/complicações , Sobrepeso , Síndrome do Ovário Policístico/complicações , Reprodutibilidade dos Testes , Adulto Jovem
20.
J Therm Biol ; 72: 148-154, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29496008

RESUMO

The metabolism of fishes is profoundly affected by environmental factors such as temperature, oxygen concentration, and pH levels. Also, biotic elements, for instance, activity levels of species, have been suggested to affect the energy demand, driving their capacity to support environmental challenges. The present work aims to investigate the effects of the lifestyle and swimming activities levels of fishes living in Amazon forest stream on the aerobic metabolism and thermal tolerance. Intermittent flow respirometry was used to measure routine metabolic rate and thermal maximum metabolic rate with a thermal ramp methodology. Critical thermal tolerance, thermal aerobic scope, and thermal factorial aerobic scope were calculated for twelve species belonging to different families. Our findings showed a correlation between routine and thermal maximum metabolic rate and, between metabolic rate and activity levels. Species belonging to Characidae and Crenuchidae families have high resting metabolic rates, which decrease their factorial aerobic scope and reduce their abilities to cope with warming events. Therefore, these species have low thermal tolerance. Instead, species from families Rivulidae and Cichlidae showed opposite metabolic results and larger thermal windows. We hypothesize that these responses are related to an evolutionary trade-off between lifestyle and energetic requirements and warming will favor species with low activity performance.


Assuntos
Adaptação Fisiológica , Peixes/metabolismo , Natação , Animais , Metabolismo Basal , Brasil , Characidae , Florestas , Temperatura Alta , Consumo de Oxigênio , Especificidade da Espécie
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