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1.
Physiol Res ; 72(S4): S381-S387, 2023 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-38116776

RESUMO

Spontaneous preterm birth (sPTB) is a major cause of perinatal morbidity and mortality, even in developed countries. Prediction of sPTB is therefore a valuable tool to reduce the associated risks. The current standard for the prediction of sPTB consists, in addition to anamnestic data, of previous sPTB and previous second trimester miscarriage, measurement of cervical length by transvaginal ultrasound (TVU CL) together with assessment of fetal fibronectin levels in cervicovaginal fluid. Other evaluation parameters, such as the level of endocannabinoids in the pregnant woman's blood, could increase the sensitivity of this management. Endocannabinoids (eCBs) are a part of the endocannabinoid system (ECS); out of them anandamide (arachidonoyl-ethanolamide, AEA), in particular, plays an important role in the regulation of pregnancy and childbirth. We present the protocol for an open, non-randomized study to evaluate concentrations of AEA and other endocannabinoids: 2 linoleoylglycerol (2-AG), 2 linoleoylglycerol (2-LG), 2 oleoylglycerol (2-OG), and 2 arachidonoyldopamine (2-ADOPA or also NADA) in the blood of pregnant women as potential predictors of sPTB. In a total of 230 women with a history of sPTB or miscarriage, eCBs levels between 22 and 28 weeks of gestation will be assessed from maternal blood, in addition to the standard procedure. The aim of the study is to determine the relationship between blood concentrations of the endocannabinoids tested and the risk of sPTB. The results of this study will describe the prognostic significance of maternal blood eCBs levels for sPTB, and could subsequently enable improved screening programs for early identification of sPTB.


Assuntos
Aborto Espontâneo , Nascimento Prematuro , Recém-Nascido , Gravidez , Feminino , Humanos , Nascimento Prematuro/diagnóstico , Endocanabinoides , Segundo Trimestre da Gravidez
2.
Plant Biol (Stuttg) ; 23(4): 653-663, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33866664

RESUMO

Interspecific differences in sensitivity of the Antarctic moss Sanionia uncinata from King George Island (KGI) and James Ross Island (JRI) to photoinhibitory treatment were studied in laboratory conditions using chlorophyll fluorescence techniques. Slow (Kautsky) and fast (OJIP) kinetics were used for the measurements. Samples were exposed to a short-term (60 min) photoinhibitory treatment (PIT, 2000 µmol·m-2 ·s-1 PAR). The photoinhibitory treatment (PIT) led to photoinhibition which was indicated by the decrease in FV /FM and ΦPSII in KGI but not in JRI samples. However, this decrease was small and full recovery was reached 90 min after PIT termination. Non-photochemical quenching (NPQ) was activated during the PIT, and rapidly relaxed during recovery. Early stages of photoinhibition showed a drop in FV /FM and ΦPSII to minimum values within the first 10 s of the PIT, with their subsequent increase apparent within fast (0-5 min PIT) and slow (5-50 min PIT) phases of adjustment. The PIT caused a decrease in the performance index (Pi_Abs), photosynthetic electron transport per reaction centre (RC) (ET0 /RC). The PIT induced an increase in thermal dissipation per RC (DI0 /RC), effectivity of thermal dissipation (Phi_D0 ), absorption per RC (ABS/RC) and trapping rate per RC (TR0 /RC). In conclusion, PIT led to only slight photoinhibition followed by fast recovery in S. uncinata from KGI and JRI, since FV /FM and ΦPSII returned to pre-photoinhibitory conditions. Therefore, S. uncinata might be considered resistant to photoinhibition even in the wet state. The KGI samples showed higher resistance to photoinhibition than the JRI samples.


Assuntos
Clorofila , Fotossíntese , Transporte de Elétrons , Fluorescência
3.
Pol J Vet Sci ; 24(4): 607-610, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35179844

RESUMO

In recent years there have been a growing number of reports on applying viruses in oncological treatment. In the present study, we demonstrated for the first time that animal virus EHV-1 productively replicates in the human adenocarcinoma cell line (A549) without the need for adaptation. Real-time PCR analysis and immunofluorescence assay showed that EHV-1 could infect and causes lysis of human lung cancer cells. According to our results, we can assume that EHV-1 has oncolytic potential.


Assuntos
Adenocarcinoma/patologia , Herpesvirus Equídeo 1 , Neoplasias Pulmonares/patologia , Vírus Oncolíticos , Células A549 , Humanos
4.
Pol J Vet Sci ; 23(2): 309-312, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32627988

RESUMO

In the present study, the influence of the infection with equine herpesvirus type 1 (non-neuro-pathogenic and neuropathogenic strains of EHV-1) on the morphology and distribution of mitochondrial network in equine dermal cell line was investigated. Our results indicate that EHV-1-infection caused changes in the mitochondrial morphology manifested mostly by fission and reactive oxygen species generation.


Assuntos
Derme/citologia , Herpesvirus Equídeo 1/fisiologia , Cavalos , Mitocôndrias/virologia , Animais , Linhagem Celular , Replicação Viral
5.
Zookeys ; 872: 69-75, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496887

RESUMO

The Chyromyidae of Turkey are reviewed and all 15 species known from the country are listed. The following are new records: Chyromya miladae Andersson, 1976, Gymnochiromyia inermis (Collin, 1933), Aphaniosoma approximatum Becker, 1903, A. micromacro Carles-Tolrá, 2001, A. propinquans Collin, 1949 and A. proximum Ebejer, 1998.

6.
Plant Biol (Stuttg) ; 20(5): 808-816, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29888486

RESUMO

We studied the resistance of Parmotrema austrosinense to UV-B stress. We focused on the effects of a high dose UV-B radiation on the content of chlorophylls, carotenoids and UV-B screening compounds. Photosynthetic parameters were measured by chlorophyll fluorescence (potential and effective quantum yields, photochemical and non-photochemical quenching) and evaluated in control and UV-B-treated lichens. Lichens from two different locations in Cordoba, Argentina, were selected: (i) high altitude and dry plots at (Los Gigantes) and (ii) lowland high salinity plots (Salinas Grandes). UV-B treatment led to a decrease in the content of photosynthetic pigments and UV-B screens (absorbance decrease in 220-350 nm) in the samples from Salinas Grandes, while in Los Gigantes samples, an increase in UV-B screen content was observed. Chlorophyll fluorescence parameters showed a UV-B-induced decline in FV /FM , ΦPSII and qP indicating limitation of primary photosynthetic processes in photosystem II (PSII) of symbiotic alga, more pronounced in Salinas Grandes samples. Protective mechanism of PSII were activated by the UV-B treatment to a higher extent in samples from Salinas Grandes (NPQ 0.48) than in Los Gigantes samples (NPQ 0.26). We concluded that site-related characteristics, and in particular different UV-B radiation regimen, had a strong effect on resistance of the photosynthetic apparatus of P. austrosinense to UV-B radiation.


Assuntos
Líquens/efeitos da radiação , Fotossíntese/efeitos da radiação , Raios Ultravioleta , Altitude , Carotenoides/análise , Carotenoides/metabolismo , Clorofila/análise , Clorofila/metabolismo , Ecossistema , Fluorescência , Líquens/química , Líquens/metabolismo , Tolerância ao Sal/efeitos da radiação
7.
Mol Ecol Resour ; 16(3): 809-22, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26602739

RESUMO

DNA sequences offer powerful tools for describing the members and interactions of natural communities. In this study, we establish the to-date most comprehensive library of DNA barcodes for a terrestrial site, including all known macroscopic animals and vascular plants of an intensively studied area of the High Arctic, the Zackenberg Valley in Northeast Greenland. To demonstrate its utility, we apply the library to identify nearly 20 000 arthropod individuals from two Malaise traps, each operated for two summers. Drawing on this material, we estimate the coverage of previous morphology-based species inventories, derive a snapshot of faunal turnover in space and time and describe the abundance and phenology of species in the rapidly changing arctic environment. Overall, 403 terrestrial animal and 160 vascular plant species were recorded by morphology-based techniques. DNA barcodes (CO1) offered high resolution in discriminating among the local animal taxa, with 92% of morphologically distinguishable taxa assigned to unique Barcode Index Numbers (BINs) and 93% to monophyletic clusters. For vascular plants, resolution was lower, with 54% of species forming monophyletic clusters based on barcode regions rbcLa and ITS2. Malaise catches revealed 122 BINs not detected by previous sampling and DNA barcoding. The insect community was dominated by a few highly abundant taxa. Even closely related taxa differed in phenology, emphasizing the need for species-level resolution when describing ongoing shifts in arctic communities and ecosystems. The DNA barcode library now established for Zackenberg offers new scope for such explorations, and for the detailed dissection of interspecific interactions throughout the community.


Assuntos
Biota , Código de Barras de DNA Taxonômico/métodos , Ecossistema , Animais , Regiões Árticas , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Groenlândia , Filogenia , Plantas , Ribulose-Bifosfato Carboxilase/genética
9.
Cryobiology ; 64(3): 215-22, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22342877

RESUMO

Unicellular algae of genus Trebouxia are the most frequent symbiotic photobionts found in lichen species adapted to extreme environments. When lichenised, they cope well with freezing temperature of polar regions, high-mountains environments and were successfully tested in open-space experiments. Trebouxia sp. is considered potential model species for exobiological experiments. The aim of this paper is to evaluate cryoresistence of Trebouxia sp. when isolated from lichen thalli and cultivated on media. In our study, six algal strains were exposed to repeated freezing/thawing cycles. The strains of Trebouxia sp. (freshly isolated from lichen Lasallia pustulata), Trebouxia erici, Trebouxia asymmetrica, Trebouxia glomerata, Trebouxia irregularis, and Trebouxia jamesii from culture collection were cooled from 25 to -40 °C at two different rates. The strains were also shock frozen in liquid nitrogen. After repeated treatment, the strains were inoculated and cultivated on a BBM agar for 7 days. Then, cell viability was assessed as relative share of living cells. Potential quantum yield of photochemical reactions in PS II (F(V)/F(M)), and effective quantum yield of photochemical reactions in PS II (Φ(PSII)) were measured. While the slow cooling rate (0.5 °C min(-1)) did not cause any change in viability, F(V)/F(M), and Φ(PSII), the fast cooling rate (6.0 °C min(-1)) caused species-specific decrease in all parameters. The most pronounced interspecific differences in cryoresistance were found after shock freezing and consequent cultivation. While T. asymmetrica and T. jamesii exhibited low viability of living cells (18.9% and 34.7%) and full suppression of photosynthetic processes, the other strains had viability over 60%, and unaffected values of F(V)/F(M), and Φ(PSII). This indicated a high degree of cryoresistance of T. glomerata, T. erici, T. irregularis and Trebouxia sp. strains. These strains could be used for detailed investigation of underlying physiological mechanisms and as models for astrobiological tests taken in the Earth facilities.


Assuntos
Clorofila/química , Criopreservação , Cianobactérias/fisiologia , Complexo de Proteína do Fotossistema II/química , Adaptação Fisiológica , Ágar , Meios de Cultura , Cianobactérias/classificação , Cianobactérias/isolamento & purificação , Congelamento , Líquens/fisiologia , Viabilidade Microbiana , Fotossíntese , Especificidade da Espécie , Espectrometria de Fluorescência , Simbiose
10.
Rozhl Chir ; 87(3): 128-34, 2008 Mar.
Artigo em Tcheco | MEDLINE | ID: mdl-18459439

RESUMO

The anatomy and histology of the normal retrocalcaneal bursa (RB) was studied on both embalmed and fresh cadaverous material. The bursa is a constant structure, its upper and posterior walls are completely covered with the unilayered synovial membrane. Its anterior wall represents the superior facet of the calcaneal tuberosity, the posterior one corresponds to the anterior surface of the insertional part of the Achilles tendon. The superior wall is formed by the adipose tissue of the inferior part of Kager's triangle, extending into the cavity of the bursa in a form of constant large and irregularly shaped synovial fold. The normal anatomical features as well as some pathological changes of the bursa and its neighbourhood were demonstrated on examples of some case reports, by use of the ultrasonography and magnetic resonance investigations. In healthy individuals the space of the bursa was not figured in the ultrasonographic investigations, but was well apparent in the MR images. The pathological changes of the bursa are detectable by using of both methods, but the MR images present substantially precise quality of depiction. The authors recommend the use of presented new anatomical data for the improvement in differential diagnostic of the wide spectrum of achillar enthesopathies.


Assuntos
Tendão do Calcâneo/patologia , Bursite/diagnóstico , Calcâneo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bolsa Sinovial/patologia , Bursite/patologia , Humanos , Masculino , Pessoa de Meia-Idade
11.
Plant Biol (Stuttg) ; 6(3): 333-41, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15143442

RESUMO

The effect of high light on spatial distribution of chlorophyll (Chl) fluorescence parameters over a lichen thallus (Umbilicaria antarctica) was investigated by imaging of Chl fluorescence parameters before and after exposure to high light (1500 micro mol m (-2) s (-1), 30 min at 5 degrees C). False colour images of F (V)/F (M) and Phi (II) distribution, taken over thallus with 0.1 mm (2) resolution, showed that maximum F (V)/F (M) and Phi (II) values were located close to the thallus centre. Minimum values were typical for thallus margins. After exposure to high light, a differential response of F (V)/F (M) and Phi (II) was found. The marginal thallus part exhibited a loss of photosynthetic activity, manifested as a lack of Chl fluorescence signal, and close-to-centre parts showed a different extent of F (V)/F (M) and Phi (II) decrease. Subsequent recovery in the dark led to a gradual return of F (V)/F (M) and Phi (II) to their initial values. Fast (30 min) and slow (1 - 22 h) phase of recovery were distinguished, suggesting a sufficient capacity of photoprotective mechanisms in U. antarctica to cope with low-temperature photoinhibition. Glutathione and xanthophyll cycle pigments were analyzed by HPLC. High light led to an increase in oxidized glutathione (GSSG), and a conversion of violaxanthin to zeaxanthin, expressed as their de-epoxidation state (DEPS). The responses of GSSG and DEPS were reversible during subsequent recovery in the dark. GSSG and DEPS were highly correlated to non-photochemical quenching (NPQ), indicating involvement of these antioxidants in the resistance of U. antarctica to high-light stress. Heterogeneity of Chl fluorescence parameters over the thallus and differential response to high light are discussed in relation to thallus anatomy and intrathalline distribution of the symbiotic alga Trebouxia sp.


Assuntos
Clorofila/metabolismo , Glutationa/metabolismo , Líquens/fisiologia , Complexo de Proteínas do Centro de Reação Fotossintética/fisiologia , beta Caroteno/metabolismo , Aclimatação/efeitos da radiação , Temperatura Baixa , Eucariotos/crescimento & desenvolvimento , Fluorometria/métodos , Líquens/citologia , Líquens/efeitos da radiação , Luz , Microscopia , Complexo de Proteínas do Centro de Reação Fotossintética/efeitos da radiação , Simbiose , Xantofilas , Zeaxantinas , beta Caroteno/análogos & derivados
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