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1.
Microbiol Spectr ; 11(3): e0053223, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37093018

RESUMO

We appraised the relationship between the biological and the chronological age and estimated the rate of biological aging in HIV-infected patients. Two independent biomarkers, the relative telomere length and iron metabolism parameters, were analyzed in younger (<35) and older (>50) HIV-infected and uninfected patients (control group). In our control group, telomeres of younger patients were significantly longer than telomeres of older ones. However, in HIV-infected participants, the difference in the length of telomeres was lost. By combining the length of telomeres with serum iron, ferritin, and transferrin iron-binding capacity, a new formula for determination of the aging process was developed. The life expectancy of the healthy population was related to their biological age, and HIV-infected patients were biologically older. The effect of antiretroviral HIV drug therapies varied with respect to the biological aging process. IMPORTANCE This article is focused on the dynamics of human aging. Moreover, its interdisciplinary approach is applicable to various systems that are aging.


Assuntos
Envelhecimento , Infecções por HIV , Humanos , Envelhecimento/metabolismo , Antirretrovirais/uso terapêutico , Ferro , Infecções por HIV/tratamento farmacológico , Telômero
2.
Environ Toxicol Pharmacol ; 92: 103853, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35318121

RESUMO

We observed different outcomes upon the subacute exposure to the 128 mT highly homogeneous static magnetic field (SMF) when its orientation was (i) aligned with the vertical component of the geomagnetic field; (ii) in the opposite direction. We employed the fatty acids (FA) composition and digital image analyses (DIA) to provide insights into the underlying processes and examine the possible weak SMF effects. Swiss-Webster male mice were whole-body exposed for 1 h/day over five days. Brain tissue's thin liquid chromatography resulted in brain FA composition, indicating a possible sequence of changes due to the SMF exposure. Quantitative DIA accurately assessed different image parameters. Delicate textural changes were revealed in the group where pathohistological or biochemical alterations have not been detected. DIA-based biological markers seem to be very promising for studying delicate tissue changes, which results from the high sensitivity and wide availability of DIA.


Assuntos
Ácidos Graxos , Campos Magnéticos , Animais , Encéfalo , Masculino , Camundongos
3.
Bioelectromagnetics ; 42(3): 238-249, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33544924

RESUMO

Different priming methods were developed to improve seed germination and the early growth of seedlings. This study aimed to examine the combined effect of bacterial inoculation and static magnetic field on white mustard (Sinapis alba L.) germination. A plant growth-promoting bacterial strain Bacillus amyloliquefaciens D5 ARV was used for biopriming. The static magnetic field of 90 mT was applied for 5 and 15 min. Analyses of abscisic acid, chlorophyll, anthocyanins, flavonoids content, nitrogen balance index, and bacterial indole-3-acetic acid were used to explain observed effects. Bacterial inoculation improved seed germination, whereas exposure to 90 mT for 15 min suppressed germination. Such an unfavorable effect was neutralized when the treatment with the static magnetic field was combined with bacterial inoculation. The highest germination percentage was a result of synergistic action of B. amyloliquefaciens D5 ARV and 15 min long exposure to 90 mT, which induced an increase of 53.20% in the number of germinated seeds. The static magnetic field induced the increase of bacterial indole-3-acetic acid production threefold times. Biomagnetic priming caused a metabolic shift from primary to secondary metabolism in the white mustard seedlings. An adequate combination of biological priming and static magnetic field treatment can be successfully used in old seed revitalization and germination improvements. © 2021 Bioelectromagnetics Society.


Assuntos
Antocianinas , Germinação , Clorofila , Plântula , Sementes
4.
Exp Gerontol ; 110: 151-157, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29906492

RESUMO

Ageing affects various physiological and metabolic processes in a body and a progressive accumulation of oxidative damage stands out as often used explanation. One of the most powerful scavenger of reactive oxygen species (ROS) in all organs is melatonin. A majority of melatonin supplied to the body via blood originates from the pineal gland. However, we have been interested in a locally produced melatonin. We have used 2.5- and 36-months-old Wistar rats. Tissues were collected and gene expression of AA-NAT and ASMT, the two key enzymes in a synthesis of melatonin, was determined in brain, liver, kidney, heart, skin, and intestine. Since melatonin can influence antioxidant enzymes, the activity of superoxide dismutase (SOD) and catalase (CAT), and the level of GSH were measured in liver. In addition, Copper (Cu), Zinc (Zn), and Manganese (Mn) were also determined in liver since these microelements might affect the activity of antioxidant enzymes. The expression of AA-NAT and ASMT was increased in liver and skin of old animals. A positive correlation in AA-NAT and ASMT expression was observed in liver, intestine and kidney. Moreover, the activity of CAT enzyme in liver was increased while SOD activity was decreased. SOD and CAT were probably affected by the observed decreased amount of Cu, Zn, and Mn in liver of old animals. In our model, extrapineal melatonin pathway in ageing consisted of complex interplay of locally produced melatonin, activities of SOD and CAT, and adequate presence of Cu, Zn and Mn microelements in order to defend organs against oxidative damage.


Assuntos
Envelhecimento/metabolismo , Fígado/metabolismo , Melatonina/metabolismo , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Cobre/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Zinco/metabolismo
5.
New Microbiol ; 41(1): 61-66, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29505065

RESUMO

The importance of oral microflora composition in HIV-infected patients is well recognized. However, no studies so far have dealt with age-related changes in periodontal pathogens occurrence in HIV+ individuals. The aim of the present study was to assess and compare temporal changes of bacteria frequency in younger (≤35 years) and older (≥50 years) HIV-infected and non-infected individuals. Bacterial DNA was isolated from buccal swabs of 30 younger and 30 older subjects in both HIV+ and HIV- groups. By means of PCR the following microorganisms were detected: Aggregatibacter actinomycetemcomitans, Eikenella corrodens, Peptostreptococcus micros, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia and Treponema denticola. Oral and periodontal examinations were performed in all subjects. The prevalence of microorganisms was significantly higher in HIV+ patients compared to controls, and their distribution showed a notable shift. The decreasing incidence in HIV- subjects was: Pi>Pm>Pg>Aa>Ec>Tf>Td whilst in HIV+ it was: Pi>Pm>Ec>Pg>Tf>Aa>Td. Oral manifestations of HIV infection were more frequent in older compared to younger patients. All measured values of clinical periodontal parameters were significantly higher in older compared to younger HIV+ patients. Ageing in HIV+ subjects is accompanied with a substantial increase and rearrangements of periodontal microflora, potentially aggravating oral and systemic health.


Assuntos
Envelhecimento/fisiologia , Infecções por HIV/complicações , Doenças Periodontais/microbiologia , Adulto , Idoso , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Periodontais/etiologia
6.
Comput Methods Programs Biomed ; 157: 153-162, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29477424

RESUMO

BACKGROUND AND OBJECTIVE: A rough estimate indicated that use of samples of size not larger than ten is not uncommon in biomedical research and that many of such studies are limited to strong effects due to sample sizes smaller than six. For data collected from biomedical experiments it is also often unknown if mathematical requirements incorporated in the sample comparison methods are satisfied. METHODS: Computer simulated experiments were used to examine performance of methods for qualitative sample comparison and its dependence on the effectiveness of exposure, effect intensity, distribution of studied parameter values in the population, and sample size. The Type I and Type II errors, their average, as well as the maximal errors were considered. RESULTS: The sample size 9 and the t-test method with p = 5% ensured error smaller than 5% even for weak effects. For sample sizes 6-8 the same method enabled detection of weak effects with errors smaller than 20%. If the sample sizes were 3-5, weak effects could not be detected with an acceptable error; however, the smallest maximal error in the most general case that includes weak effects is granted by the standard error of the mean method. The increase of sample size from 5 to 9 led to seven times more accurate detection of weak effects. Strong effects were detected regardless of the sample size and method used. CONCLUSIONS: The minimal recommended sample size for biomedical experiments is 9. Use of smaller sizes and the method of their comparison should be justified by the objective of the experiment.


Assuntos
Pesquisa Biomédica/estatística & dados numéricos , Simulação por Computador , Tamanho da Amostra , Humanos , Reprodutibilidade dos Testes
7.
Bioelectromagnetics ; 38(7): 533-540, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28700087

RESUMO

In a number of studies, a static magnetic field was observed to positively influence the growing process of various plants; however, the effect has not yet been related to possible structural changes. We investigate if the static magnetic field that improves germination of wheat also alters wheat's near-infrared spectrum. Two groups of seeds were exposed to 340 mT for 16 h cumulatively. The first group was exposed 8 days for 2 h per day, while the second group was exposed 4 h per day for 4 consecutive days. One half of each of the exposed seed groups as well as of the unexposed control groups was sown, and the other half was used for mid-infrared spectra measurements. The sown seeds were monitored for 3 weeks after sowing. Germination of the groups exposed to the magnetic field was faster compared to corresponding non-exposed groups that were grown under the same conditions. The magnetic field exposure caused the enhancement of one OH peak at 3,369 cm-1 and two CO peaks at 1,662 cm-1 and 1,740 cm-1 in the mid-infrared spectrum. The effect was more pronounced for the 4 day, 4 h/day exposure. Bioelectromagnetics. 38:533-540, 2017.© 2017 Wiley Periodicals, Inc.


Assuntos
Germinação , Campos Magnéticos , Triticum/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Espectrofotometria Infravermelho , Fatores de Tempo
8.
Int J Radiat Biol ; 92(3): 140-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26850041

RESUMO

PURPOSE: Static magnetic fields (SMF) have been widely used in research, medicine and industry. Since zinc and copper play an important role in biological systems, we studied the effects of the subchronic continuous SMF exposure on their distribution in murine tissues. MATERIALS AND METHODS: For 30 days, mice were exposed to inhomogeneous, vertical, downward or upward oriented SMF of 1 mT averaged intensity with spatial gradient in vertical direction. RESULTS: SMF decreased the amount of copper and zinc in liver. In brain, zinc levels were increased and copper levels were decreased. In spleen, zinc content was reduced, while copper amount remained unchanged. CONCLUSIONS: Subchronic exposure to SMF differently affected copper and zinc content in examined organs, and the changes were more pronounced for the downward oriented field. The outcome could be attributed to the protective, rather than the harmful effect of SMF.


Assuntos
Cobre/metabolismo , Campos Magnéticos , Vísceras/fisiologia , Vísceras/efeitos da radiação , Irradiação Corporal Total/métodos , Zinco/metabolismo , Animais , Relação Dose-Resposta à Radiação , Masculino , Camundongos , Especificidade de Órgãos/fisiologia , Especificidade de Órgãos/efeitos da radiação , Doses de Radiação , Distribuição Tecidual
9.
Environ Sci Pollut Res Int ; 23(2): 1584-97, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26377971

RESUMO

It has been shown that static magnetic field (SMF) of moderate intensity produces considerable impact on biological systems. SMF can be homogeneous or inhomogeneous. In many studies, inhomogeneous SMF was employed. Aware that inhomogeneous SMF could result in experimental variability, we investigated the influence of a vertical homogeneous SMF of different orientation. Male Swiss-Webster 9- to 10-week-old mice were subacutely exposed to upward- and downward-oriented SMF of 128 mT generated by a cyclotron for 1 h/day during a 5-day period. We found that SMF affected various organs and that these effects were, to some degree, dependent on SMF orientation. Both upward- and downward-oriented SMF caused a reduction in the amount of total white blood cells (WBC) and lymphocytes in serum, a decrease of granulocytes in the spleen, kidney inflammation, and an increase in the amount of high-density lipoprotein (HDL). In addition, upward-oriented SMF caused brain edema and increased spleen cellularity. In contrast, downward-oriented SMF induced liver inflammation and a decrease in the amount of serum granulocytes. These effects might represent a specific redistribution of pro-inflammatory cells in blood and among various organs. It appears that homogeneous SMF of 128 mT affected specific organs in the body, rather than simultaneously and equally influencing the entire body system.


Assuntos
Campos Magnéticos , Animais , Contagem de Eritrócitos , Contagem de Linfócitos , Linfócitos , Masculino , Camundongos , Baço
10.
Ecotoxicol Environ Saf ; 81: 98-105, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22627015

RESUMO

Static magnetic fields (SMFs) are time independent fields whose intensity can be spatially dependent. This study investigates influence of subchronic continuous exposure to upward and downward directed SMF on hematological parameters and spleen cellularity in mice. The experiment is performed on the Northern hemisphere; consequently, the vertical component of geomagnetic field is directed downward. Male, Swiss-Webster, 6 weeks old mice were exposed to the vertically declining SMF. Mice were divided in three groups and continuously exposed or not exposed for 28 days to the SMF characterized by the averaged field of 16 mT and averaged field gradient of 10 mT/cm. Differently oriented SMF did not alter hemoglobin and hematocrit content among the groups. However, the groups exposed to the upward and downward fields had statistically significant higher levels of serum transferrin compared to the control. Moreover, spleen cellularity in animals in the downward group was significantly higher compared to the upward and control group. In addition, spleen lymphocytes in both of the exposed groups were significantly higher than in the control group. In contrast, spleen granulocytes in the exposed groups were significantly lower than in the control group. Significant decrease was also observed in brain and liver iron content with concomitant increase of iron in serum and spleen in exposed animals. Subchronic continuous exposure to 16 mT SMF caused lymphocyte and granulocyte redistribution between spleen and blood. This distribution is typical for stress induced hematological changes. These results suggest that observed changes were not due to an unspecific stress response, but that they were rather caused by specific adaptation to subchronic SMF exposure.


Assuntos
Campos Magnéticos/efeitos adversos , Animais , Fígado/fisiologia , Linfócitos/patologia , Masculino , Camundongos , Baço/citologia , Baço/patologia
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