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1.
Ann Bot ; 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38099507

RESUMO

● Flowering is a key process in the life cycle of a plant. Climate change is shifting flowering phenologies in the Northern Hemisphere, but studies with long data series at community level are scarce, and even more so those regarding the consequences of phenological changes for emerging ecological interactions. In the Mediterranean region, the effects of climate change are stronger than the global average and there is an urgent need to understand how biodiversity will be affected in this area. ● In this study we investigated how the entire flowering phenology of a community comprising 51 perennial species from the south of the Iberian Peninsula changed from the decade of the 1980s to the 2020s. Furthermore, we have analysed the consequences of these changes for flowering order and co-flowering patterns. ● We have found that the flowering phenology of the community has advanced by about 20 days, and was coherent with the increasing temperatures related to climate change. Individual species have generally advanced their entire flowering phenology (start and end) and increased their flowering duration. The early flowering has resulted in a re-organisation of the flowering order of the community and generated a new co-flowering assemblages of species, with a slight trend towards an increase of shared flowering time among species. ● The advanced flowering phenology and changes on flower duration reported here were of unprecedented magnitude, showcasing the extreme effects of climate change on Mediterranean ecosystems. Furthermore, the effects were not similar among species, which could be attributed to differences in sensitivities of environmental cues for flowering. One consequence of these changes in flowering times is the ecological mismatches indicated by the changes in flower order and co-flowering between decades. The novel scenario may lead to new competition or facilitation interactions and to the loss or gain of pollinators.

2.
Mol Divers ; 26(5): 2443-2457, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34724138

RESUMO

A new series of 13 pyrazole-derivative compounds with potential antifungal activity were synthetized with good yields. The series have the (E)-2-((1-(R)-3,5-dimethyl-1H-pyrazol-4-yl)diazenyl)phenol general structure and were characterized by means of X-ray diffraction, UV-Vis, FTIR, 1H-NMR, 13C-NMR, and two-dimensional NMR experiments. This experimental characterization was complemented by DFT simulations. A deep insight regarding molecular reactivity was accomplished employing a conceptual DFT approach. In this sense, dual descriptors were calculated at HF and DFT level of theory and GGV spin-density Fukui functions. The main reactive region within the molecules was mapped through isosurface and condensed representations. Finally, chemical descriptors that have previously shown to be close related to biological activity were compared within the series. Thus, higher values of chemical potential ω and electrophilicity χ obtained for compounds 10, 9, 8, 6 and 7, in this order, suggest that these molecules are the better candidates as biological agents.


Assuntos
Antifúngicos , Pirazóis , Antifúngicos/farmacologia , Fatores Biológicos , Modelos Moleculares , Fenóis , Pirazóis/química , Pirazóis/farmacologia
3.
BMC Geriatr ; 22(1): 61, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35042466

RESUMO

BACKGROUND: While there is evidence about stablished risk factors (e.g., raised blood pressure) and higher mortality risk in older population, less has been explored about other functional parameters like the Timed Up and Go test and the Gait Speed in older people at low- and middle-income countries. We aimed to study these mobility tests as predictors of mortality in a population of older people in Peru. METHODS: Population-based prospective cohort study (2013-2020). Random sampling of people aged 60+ years in a community of Lima, Peru. Geriatricians conducted all clinical evaluations and laboratory tests were conducted in the local hospital. Participants were sought in the national vital registration system, and we collated cause (ICD-10) and date of death. We conducted a nested forward multivariate Cox proportional hazard model to identify all potential predictors of all-cause, communicable and non-communicable diseases mortality. RESULTS: At baseline, there were 501 older people (mean age 70.6 and 62.8% were women), complete follow-up information was available from 427 people. Mean follow-up time was 46.5 months (SD = 25.3). In multivariate models, the Timed Up and Go test was associated with higher risk of all-cause mortality (HR = 1.05; 95% CI: 1.02-1.09). For cause-specific mortality, history of heart disease (HR = 2.25; 95% CI: 1.07-4.76) and age in years (HR = 1.05; 95% CI: 1.01-1.09) were predictors of non-communicable diseases mortality. CONCLUSIONS: In addition to established risk factors for mortality in older population, the Timed Up and Go test, a functional parameter, raised as a relevant predictor of all-cause mortality.


Assuntos
Equilíbrio Postural , Idoso , Estudos de Coortes , Feminino , Humanos , Peru/epidemiologia , Estudos Prospectivos , Estudos de Tempo e Movimento
4.
Int J Mol Sci ; 23(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35216112

RESUMO

Stressor exposure increases colonic inflammation. Because inflammation leads to anxiety-like behavior, we tested whether stressor exposure in mice recovering from dextran-sulfate-sodium (DSS)-induced colitis enhances anxiety-like behavior. Mice received 2% DSS for five consecutive days prior to being exposed to a social-disruption (SDR) stressor (or being left undisturbed). After stressor exposure, their behavior was tested and colitis was assessed via histopathology and via inflammatory-cytokine measurement in the serum and colon. Cytokine and chemokine mRNA levels in the colon, mesenteric lymph nodes (MLNs), hippocampus, and amygdala were measured with RT-PCR. SDR increased anxiety-like behaviors, which correlated with serum and hippocampal IL-17A. The stressor also reduced IL-1ß, CCL2, and iNOS in the colonic tissue, but increased iNOS, IFNγ, IL-17A, and TNFα in the MLNs. A network analysis indicated that reductions in colonic iNOS were related to elevated MLN iNOS and IFNγ. These inflammatory markers were related to serum and hippocampal IL-17A and associated with anxiety-like behavior. Our data suggest that iNOS may protect against extra-colonic inflammation, and when suppressed during stress it is associated with elevated MLN IFNγ, which may coordinate gut-to-brain inflammation. Our data point to hippocampal IL-17A as a key correlate of anxiety-like behavior.


Assuntos
Ansiedade/metabolismo , Colite/metabolismo , Citocinas/metabolismo , Hipocampo/metabolismo , Inflamação/metabolismo , Animais , Ansiedade/patologia , Colite/patologia , Colo/metabolismo , Colo/patologia , Modelos Animais de Doenças , Hipocampo/patologia , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
5.
J Pediatr Gastroenterol Nutr ; 73(4): 499-506, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34238825

RESUMO

OBJECTIVES: Polyethylene Glycol 3350 (PEG3350) is a laxative commonly used to treat constipation in children. The Food and Drug Administration has received reports of increased anxiety, aggression, and obsessive--compulsive behaviors in children administered PEG3350. Thus, we assessed whether daily administration of PEG3350 leads to anxiety-like behavior in mice. METHODS: Outbred CD-1 IGS mice were administered either a high or a low dose of PEG3350 via daily oral gavage for 2 weeks. As a laxative comparison and control, additional mice were given a high or low dose of magnesium citrate or vehicle (water). Weight and stool consistency were assessed after each gavage to determine laxative effectiveness. Anxiety-like behaviors were assessed using light/dark, open field, and elevated plus maze (EPM) tests at baseline, after 2 weeks of daily gavage, and after a 2 week washout in experiment 1, and after 2 weeks of daily gavage in experiment 2. Stool samples were collected for microbiome analysis in experiment 2 at baseline, after 2 weeks of daily gavage, and after 2 weeks washout. RESULTS: PEG3350 and magnesium citrate significantly changed stool consistency, as well as microbiome alpha and beta diversity. Anxiety-like behaviors were not, however, different in mice administered low or high doses of PEG3350 or magnesium citrate. CONCLUSIONS: Although changes in stool consistency and the gut microbiome occurred, administration of PEG3350 did not alter anxiety-like behaviors.


Assuntos
Microbioma Gastrointestinal , Laxantes , Animais , Camundongos , Polietilenoglicóis , Resultado do Tratamento
6.
J Clin Psychol ; 76(5): 831-840, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31926023

RESUMO

For generations, veterans have answered the call to service and served their country honorably and with distinction. Unfortunately, the consequences of combat cause many veterans to struggle with life after the military and with readjustment/reintegration into civilian life. Today more than ever, there are a multitude of resources, education, and treatment options for combat veterans. For mental and physical health providers, business leaders, and other professionals who work with veterans, it is of the upmost importance that they learn about programs around them that are successful in treating veterans. The current article reviews two U.S. Department of Veterans Affairs nationwide programs-the Readjustment Counseling Service/Vet Center and Veteran Cultural Competence Training-designed to decrease mental health stigma for veterans and to increase veteran engagement with mental health services. These programs highlight the importance of being aware of the culture within military systems, being aware of personal biases, and fostering an environment of genuineness, safety, and nonjudgmental empathy. In doing so, these programs are successful in reducing the unspoken power of stigmatization; they effectively reach out to veterans in need, providing a lifeline in the dark.


Assuntos
Saúde Mental , Estereotipagem , Veteranos/psicologia , Empatia , Humanos , Serviços de Saúde Mental , Pacientes Desistentes do Tratamento , Transtornos de Estresse Pós-Traumáticos/terapia , Estados Unidos , United States Department of Veterans Affairs
7.
Artigo em Inglês | MEDLINE | ID: mdl-30602522

RESUMO

Fascioliasis is an infectious parasitic disease distributed globally and caused by the liver fluke Fasciola hepatica or F. gigantica This neglected tropical disease affects both animals and humans, and it represents a latent public health problem due to the significant economic losses related to its effects on animal husbandry. For decades, triclabendazole has been the unique anti-Fasciola drug that can effectively treat this disease. However, triclabendazole resistance in fascioliasis has more recently been reported around the world, and thus, the discovery of novel drugs is an urgent need. The aim of this study was to investigate the fasciocidal properties of 400 compounds contained in the Pathogen Box. The first stage of the screening was carried out by measuring the fasciocidal activity on metacercariae at a concentration of 33 µM each compound (the standard dose). Subsequently, the activities of the most active compounds (n = 33) at their 50% inhibitory concentration (IC50) values against metacercariae were assayed, and the results showed that 13 compounds had IC50s of ≤10 µM. The second stage queried the activities of these compounds at 33 µM against adult flukes, with seven of the compounds producing high mortality rates of >50%. Four hit compounds were selected on the basis of their predicted nontoxic properties, and the IC50 values obtained for adult worms were <10 µM; thus, these compounds represented the best fasciocidal compounds tested here. A cytotoxicity assay on four types of cell lines demonstrated that three compounds were nontoxic at their most active concentration. In conclusion, three hit compounds identified in this proof-of-concept study are potential candidates in the discovery of new fasciocidal drugs. Further studies are warranted.


Assuntos
Anti-Helmínticos/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Fasciola hepatica/efeitos dos fármacos , Fasciolíase/tratamento farmacológico , Animais , Resistência a Medicamentos , Fasciolíase/parasitologia , Humanos , Metacercárias/efeitos dos fármacos , Testes de Sensibilidade Parasitária , Triclabendazol/farmacologia
8.
Langmuir ; 34(32): 9402-9409, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-30021439

RESUMO

Plasmonic nanoparticles, especially gold ones, have been widely employed as photosensitizers in photoelectrovoltaic or photocatalytic systems. To improve the system's performance, a greater interaction of the nanoparticles with the semiconductor, generally TiO2, is desired. Moreover, this performance is enhanced when an efficient covering of TiO2 surface by the sensitizer is achieved. The Brust-Schiffrin-like methods are of the most employed approaches for nanoparticles synthesis. In a traditional approach, the reduction of the gold precursor is performed in the presence of a stabilizer (typically a thiol molecule) free in solution. A second step in which the obtained nanoparticles are anchored to the semiconductor surface is necessary in the case of photosensitive applications. Drawbacks like steric hindrance turn more difficult the covering of the semiconductor's surface by nanoparticles. In this paper, we report a variation of this methodology, where the linker is previously anchored to the TiO2 nanoparticles surface. The resulting system is employed as the stabilizer in the gold reduction step. This strategy is carried out in aqueous media in two simple steps. A great covering of the titania surface by gold nanoparticles is achieved in all cases and the gold nanoparticles in the resulting nanoaggregate might be useful for photoelectrovoltaic or photocatalytic applications.

9.
Am J Bot ; 105(12): 2065-2074, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30536384

RESUMO

PREMISE OF THE STUDY: Although an evolutionary link between breeding system and dispersibility has been proposed, to date empirical data and theoretical models of plants show contrasting trends. METHODS: We tested two competing hypotheses for the association between breeding systems and dispersibility in the heterocarpic Hypochaeris salzmanniana (Asteraceae) by using both an experimental approach and surveys over 2 years of five natural populations along an environmental cline with a gradient of pollinator availability. KEY RESULTS: Hypochaeris salzmanniana produced two types of fruits, beaked (BF) and nonbeaked (NBF), which differ in their dispersal ability. The BF were lighter and had a lower dropping velocity and higher dispersal distance than the NBF. Potential for long-distance dispersal, measured as BF ratio per head, had high narrow-sense heritability. Greater dispersibility and selfing ability were linked at all the scales studied. Both selfed BF and NBF fruits had longer plumes and lower plume loading than outcrossed fruits, characteristics that promote farther dispersal. Natural populations with a higher percentage of self-compatible plants showed a higher BF ratio. Moreover, selfing led to a higher BF ratio than outcrossing. CONCLUSIONS: The avoidance of inbreeding depression seems to be the most plausible selective pressure for the greater dispersibility traits of selfed seeds. Furthermore, the ability to modulate the BF ratio and thus the potential for long-distance dispersal of offspring based on its selfed or outcrossed origin could be advantageous, and therefore selected, under unpredictable pollination environments that favor higher dispersive selfers, which overcome both pollen limitation and inbreeding avoidance.


Assuntos
Asteraceae/fisiologia , Frutas/fisiologia , Polinização , Dispersão de Sementes , Autofertilização , Asteraceae/anatomia & histologia , Evolução Biológica , Frutas/anatomia & histologia , Seleção Genética
10.
Gac Med Mex ; 154(2): 209-216, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-29733061

RESUMO

Introduction: Physicians and medical students need to understand numerical and graphical health data in order to provide patients with correct information. Objective: The graphical and numerical skills of medical students and residents from a private university in Lima, Peru, were determined in this investigation. Method: Cross-sectional, descriptive study. The Objective Numeracy, Subjective Numeracy and Graph Literacy Scales were applied to medical students at their two final years of medical school and to medical residents. Results: Of 169 participants, 52.07% were sixth-year and 18.34% were seventh-year students and 29.58% were residents. Mean objective numeracy score was 7.34, mean subjective numeracy was 34.12 and mean graph literacy was 10.35. A multiple linear regression analysis showed that Subjective and Objective Numeracy Scales highest means were associated with the male gender and training on research methodology (p < 0.05). Graph Literacy Scale highest means were associated with the male gender and younger age (p-value < 0.05). Conclusion: Numeracy and Graph Literacy Scales mean scores were high in medical students.


Introducción: Los médicos y estudiantes de medicina necesitan comprender los datos numéricos y gráficos sobre salud para proveer información correcta a los pacientes. Objetivo: Determinar las habilidades gráficas y numéricas en estudiantes y residentes de medicina de una universidad privada de Lima, Perú. Método: Estudio descriptivo, transversal. Se aplicaron las escalas de Habilidad Numérica Objetiva, de Habilidad Numérica Subjetiva y de Habilidad Gráfica a estudiantes de medicina de los dos últimos años de la carrera de medicina y a residentes de medicina. Resultados: De 169 participantes, 52.07 % fueron estudiantes de sexto año, 18.34 % de séptimo y 29.58 % residentes. La media en la habilidad numérica objetiva fue de 7.34, en la subjetiva de 34.12 y en la habilidad gráfica de 10.35. De la regresión lineal múltiple se obtuvo que las medias más altas en las escalas de Habilidad Numérica Subjetiva y Objetiva estuvieron asociadas con el sexo masculino y la capacitación sobre metodología en investigación (p < 0.05). En la Escala de Habilidad Gráfica, las medias más altas estuvieron asociadas con el sexo masculino y menor edad (p < 0.05). Conclusión: Las medias de las escalas de Habilidad Gráfica y Habilidad Numérica en estudiantes de medicina fueron altas.


Assuntos
Educação de Pós-Graduação em Medicina , Educação Médica , Conceitos Matemáticos , Competência Profissional , Estatística como Assunto , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , México , Instalações Privadas , Faculdades de Medicina , Adulto Jovem
11.
Hum Reprod ; 32(4): 743-749, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28333245

RESUMO

Study question: Do external factors affect euploidy in egg donor cycles? Summary answer: The study demonstrates that during human assisted reproduction, embryonic chromosome abnormalities may be partly iatrogenic. What is known already: Chromosome abnormalities have been linked in the past to culture conditions such as temperature and Ph variations, as well as hormonal stimulation. Those reports were performed with older screening techniques (FISH), or ART methods no longer in use, and the subjects studied were not a homogeneous group. Study design, size, duration: A total of 1645 donor oocyte cycles and 13 282 blastocyst biopsies from 42 fertility clinics were included in this retrospective cohort study. Samples from donor cycles with PGS attempted between September 2011 and July 2015 were included. Participants/materials, setting, methods: PGS cycles from multiple fertility clinics referred to Reprogenetics (Livingston, NJ) that involved only oocyte donation were included in this study. Testing was performed by array comparative genomic hybridization (aCGH). Ploidy data were analyzed using Generalized Linear Mixed Models with logistic regression using a logit link function considering a number of variables that represent fixed and random effects. Main results and the role of chance: Euploidy rate was associated with the referring center and independent of almost all the parameters examined except donor age and testing technology. Average euploidy rate per center ranged from 39.5 to 82.5%. The mean expected rate of euploidy was 68.4%, but there are variations in this rate associated with the center effect. Limitations, reasons for caution: Data set does not include details of the donor selection process, donor race or ethnic origin, ovarian reserve or ovarian responsiveness. Due to the retrospective nature of the study, associations are apparent, however, causality cannot be established. Discrepancies in regard to completeness and homogeneity of data exist due to data collection from over 40 different clinics. Wider implications of the findings: This is the first study to show a strong association between center-specific ART treatment practices and the incidence of chromosome abnormality in human embryos, although the meiotic or mitotic origin of these abnormalities could not be determined using these technologies. Given the widespread applications of ART in both subfertile and fertile populations, our findings should be of interest to the medical community in general as well as the ART community in particular. Study funding/competing interest(s): No external funds were used for this study. S. Munne is a founding principle of Reprogenetics/current employee of Cooper Genomics. M Alikani's spouse is a founding principle of Reprogenetics/current consultant for Cooper Genomics. The remaining authors have no conflicts to declare.


Assuntos
Aberrações Cromossômicas/embriologia , Ploidias , Técnicas de Reprodução Assistida/normas , Adulto , Hibridização Genômica Comparativa , Destinação do Embrião/normas , Feminino , Fertilidade , Humanos , Doação de Oócitos/normas , Guias de Prática Clínica como Assunto , Diagnóstico Pré-Implantação , Estudos Retrospectivos
12.
Neural Plast ; 2016: 8742725, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26885406

RESUMO

Occupational exposure to complex blends of organic solvents is believed to alter brain functions among workers. However, work environments that contain organic solvents are also polluted with background noise which raises the issue of whether or not the noise contributed to brain alterations. The purpose of the current study was to determine whether or not repeated exposure to low intensity noise with and without exposure to a complex blend of organic solvents would alter brain activity. Female Fischer344 rats served as subjects in these experiments. Asynchronous volume conductance between the midbrain and cortex was evaluated with a slow vertex recording technique. Subtoxic solvent exposure, by itself, had no statistically significant effects. However, background noise significantly suppressed brain activity and this suppression was exacerbated with solvent exposure. Furthermore, combined exposure produced significantly slow neurotransmission. These abnormal neurophysiologic findings occurred in the absence of hearing loss and detectable damage to sensory cells. The observations from the current experiment raise concern for all occupations where workers are repeatedly exposed to background noise or noise combined with organic solvents. Noise levels and solvent concentrations that are currently considered safe may not actually be safe and existing safety regulations have failed to recognize the neurotoxic potential of combined exposures.


Assuntos
Encéfalo/efeitos dos fármacos , Hidrocarbonetos/toxicidade , Ruído , Solventes/toxicidade , Animais , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Feminino , Exposição Ocupacional , Ratos , Ratos Endogâmicos F344 , Transmissão Sináptica/efeitos dos fármacos
13.
J Strength Cond Res ; 30(7): 1968-74, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26670993

RESUMO

Balsalobre-Fernández, C, Kuzdub, M, Poveda-Ortiz, P, and Campo-Vecino, Jd. Validity and reliability of the PUSH wearable device to measure movement velocity during the back squat exercise. J Strength Cond Res 30(7): 1968-1974, 2016-The purpose of this study was to analyze the validity and reliability of a wearable device to measure movement velocity during the back squat exercise. To do this, 10 recreationally active healthy men (age = 23.4 ± 5.2 years; back squat 1 repetition maximum [1RM] = 83 ± 8.2 kg) performed 3 repetitions of the back squat exercise with 5 different loads ranging from 25 to 85% 1RM on a Smith Machine. Movement velocity for each of the total 150 repetitions was simultaneously recorded using the T-Force linear transducer (LT) and the PUSH wearable band. Results showed a high correlation between the LT and the wearable device mean (r = 0.85; standard error of estimate [SEE] = 0.08 m·s) and peak velocity (r = 0.91, SEE = 0.1 m·s). Moreover, there was a very high agreement between these 2 devices for the measurement of mean (intraclass correlation coefficient [ICC] = 0.907) and peak velocity (ICC = 0.944), although a systematic bias between devices was observed (PUSH peak velocity being -0.07 ± 0.1 m·s lower, p ≤ 0.05). When measuring the 3 repetitions with each load, both devices displayed almost equal reliability (Test-retest reliability: LT [r = 0.98], PUSH [r = 0.956]; ICC: LT [ICC = 0.989], PUSH [ICC = 0.981]; coefficient of variation [CV]: LT [CV = 4.2%], PUSH [CV = 5.0%]). Finally, individual load-velocity relationships measured with both the LT (R = 0.96) and the PUSH wearable device (R = 0.94) showed similar, very high coefficients of determination. In conclusion, these results support the use of an affordable wearable device to track velocity during back squat training. Wearable devices, such as the one in this study, could have valuable practical applications for strength and conditioning coaches.


Assuntos
Acelerometria/instrumentação , Teste de Esforço/instrumentação , Treinamento Resistido/métodos , Adolescente , Adulto , Exercício Físico/fisiologia , Teste de Esforço/métodos , Humanos , Masculino , Reprodutibilidade dos Testes , Treinamento Resistido/instrumentação , Smartphone , Suporte de Carga/fisiologia , Adulto Jovem
15.
J Toxicol Environ Health A ; 78(18): 1154-69, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26408153

RESUMO

More than 800 million L/d of hydrocarbon fuels is used to power cars, boats, and jet airplanes. The weekly consumption of these fuels necessarily puts the public at risk for repeated inhalation exposure. Recent studies showed that exposure to hydrocarbon jet fuel produces lethality in presynaptic sensory cells, leading to hearing loss, especially in the presence of noise. However, the effects of hydrocarbon jet fuel on the central auditory nervous system (CANS) have not received much attention. It is important to investigate the effects of hydrocarbons on the CANS in order to complete current knowledge regarding the ototoxic profile of such exposures. The objective of the current study was to determine whether inhalation exposure to hydrocarbon jet fuel might affect the functions of the CANS. Male Fischer 344 rats were randomly divided into four groups (control, noise, fuel, and fuel + noise). The structural and functional integrity of presynaptic sensory cells was determined in each group. Neurotransmission in both peripheral and central auditory pathways was simultaneously evaluated in order to identify and differentiate between peripheral and central dysfunctions. There were no detectable effects on pre- and postsynaptic peripheral functions. However, the responsiveness of the brain was significantly depressed and neural transmission time was markedly delayed. The development of CANS dysfunctions in the general public and the military due to cumulative exposure to hydrocarbon fuels may represent a significant but currently unrecognized public health issue.


Assuntos
Doenças Auditivas Centrais/fisiopatologia , Poluentes Ambientais/toxicidade , Hidrocarbonetos/toxicidade , Sistema Nervoso/efeitos dos fármacos , Animais , Doenças Auditivas Centrais/induzido quimicamente , Masculino , Distribuição Aleatória , Ratos , Ratos Endogâmicos F344
16.
J Mol Evol ; 78(1): 24-37, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24271855

RESUMO

Flightin is a thick filament protein that in Drosophila melanogaster is uniquely expressed in the asynchronous, indirect flight muscles (IFM). Flightin is required for the structure and function of the IFM and is indispensable for flight in Drosophila. Given the importance of flight acquisition in the evolutionary history of insects, here we study the phylogeny and distribution of flightin. Flightin was identified in 69 species of hexapods in classes Collembola (springtails), Protura, Diplura, and insect orders Thysanura (silverfish), Dictyoptera (roaches), Orthoptera (grasshoppers), Pthiraptera (lice), Hemiptera (true bugs), Coleoptera (beetles), Neuroptera (green lacewing), Hymenoptera (bees, ants, and wasps), Lepidoptera (moths), and Diptera (flies and mosquitoes). Flightin was also found in 14 species of crustaceans in orders Anostraca (water flea), Cladocera (brine shrimp), Isopoda (pill bugs), Amphipoda (scuds, sideswimmers), and Decapoda (lobsters, crabs, and shrimps). Flightin was not identified in representatives of chelicerates, myriapods, or any species outside Pancrustacea (Tetraconata, sensu Dohle). Alignment of amino acid sequences revealed a conserved region of 52 amino acids, referred herein as WYR, that is bound by strictly conserved tryptophan (W) and arginine (R) and an intervening sequence with a high content of tyrosines (Y). This motif has no homologs in GenBank or PROSITE and is unique to flightin and paraflightin, a putative flightin paralog identified in decapods. A third motif of unclear affinities to pancrustacean WYR was observed in chelicerates. Phylogenetic analysis of amino acid sequences of the conserved motif suggests that paraflightin originated before the divergence of amphipods, isopods, and decapods. We conclude that flightin originated de novo in the ancestor of Pancrustacea > 500 MYA, well before the divergence of insects (~400 MYA) and the origin of flight (~325 MYA), and that its IFM-specific function in Drosophila is a more recent adaptation. Furthermore, we propose that WYR represents a novel myosin coiled-coil binding motif.


Assuntos
Artrópodes/genética , Sequência Conservada/genética , Proteínas de Drosophila/genética , Filaminas/genética , Proteínas Musculares/genética , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/genética , Artrópodes/metabolismo , Evolução Biológica , Drosophila melanogaster , Evolução Molecular , Voo Animal , Variação Genética , Miosinas/genética , Filogenia , Alinhamento de Sequência
17.
Am J Bot ; 101(9): 1456-65, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25253706

RESUMO

UNLABELLED: • PREMISE OF THE STUDY: Whole genome duplication (WGD) and specific polyploidy events marked turning points for angiosperm genome structure and evolution. Therefore, cytogenetic studies of polyploidy-prone groups such as the tropical Malvaceae and plant formations such as as the Brazilian Cerrado have gained further importance. We present new chromosome counts for Cerrado Bombacoideae and revised chromosome numbers for the Malvaceae s.l., compare these between subfamilies, and relate them to phylogenetic signal.• METHODS: We studied the chromosome number of Eriotheca candolleana, E. gracilipes, E. pubescens, Pachira glabra, Pseudobombax longiflorum, and P. tomentosum. We also compared Eriotheca species ploidy levels using flow cytometry. We compiled chromosome numbers for 557 species of Malvaceae s.l., including 37 Bombacoideae species. We included this information in a phylogenetic reconstruction based on chloroplast matK-trnK DNA to evaluate chromosome evolution of the Malvaceae s.l. and the Bombacoideae in particular.• KEY RESULTS: The Cerrado Bombacoideae presented consistently high chromosome numbers. Numbers for Eriotheca species were among the highest and varied among populations. Flow cytometry analyses showed similar 1Cx DNA for all cytotypes and indicated neopolyploidy. Chromosome numbers differed between subfamilies, with the lowest numbers in the Malvoideae and Byttnerioideae and the highest in Tilioideae. Chromosome numbers had significant phylogenetic signal for Bombacoideae but not for Malvoideae or Malvaceae s.l.• CONCLUSIONS: Clearly distinct chromosome numbers allied to monophyly provide some support for a circumscription of the Bombacoideae and distinction within the Malvaceae. The phylogenetic signal for chromosome number supports the idea of an ancient WGD and further neopolyploidy events as important evolutionary trends for the Bombacoideae.


Assuntos
Evolução Biológica , Cromossomos de Plantas , Malvaceae/genética , Filogenia , Poliploidia , Brasil , DNA de Cloroplastos/análise
18.
J Toxicol Environ Health A ; 77(5): 261-80, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24588226

RESUMO

Jet propulsion fuel-8 (JP-8) is a kerosene-based fuel that is used in military jets. The U.S. Armed Services and North Atlantic Treaty Organization countries adopted JP-8 as a standard fuel source and the U.S. military alone consumes more than 2.5 billion gallons annually. Preliminary epidemiologic data suggested that JP-8 may interact with noise to induce hearing loss, and animal studies revealed damage to presynaptic sensory cells in the cochlea. In the current study, Long-Evans rats were divided into four experimental groups: control, noise only, JP-8 only, and JP-8 + noise. A subototoxic level of JP-8 was used alone or in combination with a nondamaging level of noise. Functional and structural assays of the presynaptic sensory cells combined with neurophysiologic studies of the cochlear nerve revealed that peripheral auditory function was not affected by individual exposures and there was no effect when the exposures were combined. However, the central auditory nervous system exhibited impaired brainstem encoding of stimulus intensity. These findings may represent important and major shifts in the theoretical framework that governs current understanding of jet fuel and/or jet fuel + noise-induced ototoxicity. From an epidemiologic perspective, results indicate that jet fuel exposure may exert consequences on auditory function that may be more widespread and insidious than what was previously shown. It is possible that a large population of military personnel who are suffering from the effects of jet fuel exposure may be misidentified because they would exhibit normal hearing thresholds but harbor a "hidden" brainstem dysfunction.


Assuntos
Doenças Auditivas Centrais/induzido quimicamente , Tronco Encefálico/efeitos dos fármacos , Hidrocarbonetos/toxicidade , Animais , Limiar Auditivo/efeitos dos fármacos , Cóclea/efeitos dos fármacos , Cóclea/fisiopatologia , Feminino , Masculino , Ruído/efeitos adversos , Distribuição Aleatória , Ratos , Ratos Long-Evans
19.
Biomedicines ; 12(1)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38255320

RESUMO

Psychological stress exposure is well recognized to exacerbate inflammatory bowel disease (IBD) but the mechanisms involved remain poorly understood. In this study, chronic T cell-mediated colitis was induced by adoptively transferring CD4+CD45RBhigh splenic T cells from C57BL/6 WT donor mice into Rag1tm1Mom mice. Two weeks after T cell transfer, mice were exposed to a prolonged restraint stressor (RST) for 8 h per day for 6 consecutive days. The colitis phenotype was assessed via histopathology and semi-quantitative rt-PCR at humane endpoints or 10 weeks post-T-cell transfer. Mice that received the T cell transplant developed chronic colitis marked by increases in colonic histopathology and inflammatory cytokines. Colonic histopathology was greater in males than females regardless of RST exposure but RST exposure increased histopathology scores in females such that they reached scores observed in the males. This pattern was consistent with cytokine gene expression and protein levels in the colon (especially for IFN-γ, IL-17A, and TNF-α). Serum cytokine levels were not strongly affected by exposure to the stressor. Using a murine model of chronic T cell-mediated colitis, this study demonstrates that biological sex strongly influences colonic inflammation and exposure to chronic stress has a more pronounced effect in females than in males.

20.
Pathogens ; 13(6)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38921738

RESUMO

Fasciola hepatica has a complex lifecycle with multiple intermediate and definitive hosts and influenced by environmental factors. The disease causes significant morbidity in children and its prevalent worldwide. There is lack of data about distribution and burden of the disease in endemic regions, owing to poor efficacy of the different diagnostic methods used. A novel PCR-based test was developed by using a portable mini-PCR® platform to detect Fasciola sp. DNA and interpret the results via a fluorescence viewer and smartphone image analyzer application. Human stool, snail tissue, and water samples were used to extract DNA. Primers targeting the ITS-1 of the 18S rDNA gene of Fasciola sp. were used. The limit of detection of the mini-PCR test was 1 fg/µL for DNA samples diluted in water, 10 fg/µL for Fasciola/snail DNA scramble, and 100 fg/µL for Fasciola/stool DNA scramble. The product detection by agarose gel, direct visualization, and image analyses showed the same sensitivity. The Fh mini-PCR had a sensitivity and specificity equivalent to real-time PCR using the same specimens. Testing was also done on infected human stool and snail tissue successfully. These experiments demonstrated that Fh mini-PCR is as sensitive and specific as real time PCR but without the use of expensive equipment and laboratory facilities. Further testing of multiple specimens with natural infection will provide evidence for feasibility of deployment to resource constrained laboratories.

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