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1.
BMC Womens Health ; 23(1): 486, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37700310

RESUMO

BACKGROUND: The current paper analyzed the effect of the pandemic-induced lockdown on maternal mental health during the first 12 postpartum weeks in Germany. METHODS: In this cohort study, we compared the participants' anamnestic backgrounds and the results of psychological tests, measuring stress levels, depressive symptoms and attachment. The 327 participants were divided into two groups with one representing the "pre-COVID" sample and the other the "lockdown" sample. We performed multiple comparisons, investigating the distribution of diagnoses and the correlating risk profiles between the two cohorts. RESULTS: Our analysis showed a significant difference between the two cohorts, with a 13.2% increase in the prevalence of adjustment disorders (AD), but not postpartum depression (PPD), in the first 12 weeks postpartum. However, during the pandemic, women with AD had fewer risk factors compared to their pre-pandemic counterparts. In the "lockdown" cohort, a tendency toward higher stress and lower mother-child attachment was observed in AD. CONCLUSIONS: In sum, we observed some negative impact of the pandemic on maternal mental health. The lockdown might have contributed to an increase in the number of cases involving AD in the postpartum period. The prevalence of PPD (ca. 6-10%), on the other hand, was not affected by the lockdown. Thus, the effect of COVID-19 on maternal mental health might not, after all, have been as severe as assumed at the beginning of the pandemic.


Assuntos
Transtornos de Adaptação , COVID-19 , Humanos , Feminino , Transtornos de Adaptação/epidemiologia , COVID-19/epidemiologia , Estudos de Coortes , Controle de Doenças Transmissíveis , Pandemias , Alemanha/epidemiologia , Período Pós-Parto
2.
Nat Cell Biol ; 2(5): 288-95, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10806480

RESUMO

When co-translationally inserted into endoplasmic reticulum (ER) membranes, newly synthesized proteins encounter the lumenal environment of the ER, which contains chaperone proteins that facilitate the folding reactions necessary for protein oligomerization, maturation and export from the ER. Here we show, using a temperature-sensitive variant of vesicular stomatitis virus G protein tagged with green fluorescent protein (VSVG-GFP), and fluorescence recovery after photobleaching (FRAP), the dynamics of association of folded and misfolded VSVG complexes with ER chaperones. We also investigate the potential mechanisms underlying protein retention in the ER. Misfolded VSVG-GFP complexes at 40 degrees C are highly mobile in ER membranes and do not reside in post-ER compartments, indicating that they are not retained in the ER by immobilization or retrieval mechanisms. These complexes are immobilized in ATP-depleted or tunicamycin-treated cells, in which VSVG-chaperone interactions are no longer dynamic. These results provide insight into the mechanisms of protein retention in the ER and the dynamics of protein-folding complexes in native ER membranes.


Assuntos
Retículo Endoplasmático/química , Retículo Endoplasmático/metabolismo , Glicoproteínas de Membrana , Dobramento de Proteína , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Antibacterianos/farmacologia , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Células COS , Ditiotreitol/farmacologia , Genes Reporter , Glicosilação , Proteínas de Fluorescência Verde , Indicadores e Reagentes/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Temperatura , Tunicamicina/farmacologia
3.
Nature ; 435(7040): 313-6, 2005 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-15902250

RESUMO

The nature of ultrahigh-energy cosmic rays (UHECRs) at energies >10(20) eV remains a mystery. They are likely to be of extragalactic origin, but should be absorbed within approximately 50 Mpc through interactions with the cosmic microwave background. As there are no sufficiently powerful accelerators within this distance from the Galaxy, explanations for UHECRs range from unusual astrophysical sources to exotic string physics. Also unclear is whether UHECRs consist of protons, heavy nuclei, neutrinos or gamma-rays. To resolve these questions, larger detectors with higher duty cycles and which combine multiple detection techniques are needed. Radio emission from UHECRs, on the other hand, is unaffected by attenuation, has a high duty cycle, gives calorimetric measurements and provides high directional accuracy. Here we report the detection of radio flashes from cosmic-ray air showers using low-cost digital radio receivers. We show that the radiation can be understood in terms of the geosynchrotron effect. Our results show that it should be possible to determine the nature and composition of UHECRs with combined radio and particle detectors, and to detect the ultrahigh-energy neutrinos expected from flavour mixing.

4.
J Immunol Methods ; 204(2): 189-92, 1997 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-9212836

RESUMO

We compared the effect of human endothelial cell culture supernatant (HECS), ESG (Ewing sarcoma growth factor), IL-6 (interleukin-6) and peritoneal macrophages on the recovery of hybridoma cells after fusion with respect to growth, stability and distribution of isotype variants. A selective growth of murine IgM-producing hybridoma cells was observed in the presence of HECS after cell fusion.


Assuntos
Endotélio Vascular/citologia , Hibridomas/imunologia , Imunoglobulina M/biossíntese , Animais , Humanos , Imunoglobulina G/biossíntese , Interleucina-6/farmacologia , Camundongos , Camundongos Endogâmicos BALB C
5.
J Steroid Biochem Mol Biol ; 54(5-6): 201-10, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7577701

RESUMO

The effect of estrogen structure on the conformation of the complex formed with estrogen receptor (ER) and the consensus estrogen response element (EREc) has been examined with gel mobility shift assay. Proteins in MCF-7 cell extracts formed three distinct complexes with ERE. Only the slowest moving complex contained ER as indicated by binding with anti-ER antibodies H222 and D547. This ER-ERE complex displayed increased electrophoretic mobility when formed in the presence of estradiol (E2) and bound radiolabeled 16 alpha-iodoestradiol. The antiestrogen ICI 164,384 decreased the mobility of the ER-ERE complex and blocked the effect of E2. The results reported here indicate that the position and location of hydroxyl groups on the estratriene nucleus is an important factor in determining the mobility of ER-EREc (or a variant ERE) in gel shift assays. The ability of E2 analogs to cause conformational changes detectable as altered mobility was not directly related either to their binding affinity for ER or to their ability to activate E2 responsive genes. Although several dihydroxyestrogens (estradiol-16 alpha, 1- and 2-hydroxyestratrien-17 beta-ol) caused an increase in the mobility of the ER-EREc, other ligands (estradiol-17 alpha, 4-hydroxyestratriene-17 beta-ol, 3-hydroxy estratriene, estratrien-17 beta-ol and 5-androsten-3 beta, 17 beta-diol) with a capacity for activating at least some E2 responsive genes in MCF-7 cells had little or no effect. On the basis of these and previously published results, it can be concluded that specific structure features of estrogens are responsible for conformational changes of ER-ERE complexes detectable in gel-shift assays. Furthermore, the identified structural characteristics of the ligand which are required for gel-shift are not the same as those previously reported to be essential for stimulation of transcriptional activity of ER.


Assuntos
DNA/metabolismo , Estrogênios/metabolismo , Receptores de Estrogênio/metabolismo , Sequência de Bases , DNA/química , Estrogênios/química , Feminino , Humanos , Dados de Sequência Molecular , Ligação Proteica , Conformação Proteica , Receptores de Estrogênio/química , Ativação Transcricional , Células Tumorais Cultivadas
6.
Life Sci ; 45(23): 2225-31, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2601575

RESUMO

A study has been made to test the hypothesis that general anesthetics such as urethane are able to inhibit light from a firefly reaction mixture. Urethane was found to reduce light emission in a dose-dependent manner, the minimal effective concentration being about 20 mM. Dixon plots gave a Ki value in the range of 175 to 215 mM. Lineweaver-Burk plots showed that urethane increases the apparent Km for ATP and reduces Vmax for the reaction. This is taken to mean that urethane acts as both a competitive and non-competitive inhibitor of the firefly light reaction (mixed-type inhibition).


Assuntos
Besouros/fisiologia , Medições Luminescentes , Uretana/farmacologia , Animais , Luciferina de Vaga-Lumes/antagonistas & inibidores , Luciferases/antagonistas & inibidores
7.
Int J Radiat Biol ; 70(4): 393-401, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8862450

RESUMO

In this report, in situ hybridization with whole chromosome painting probes was used to paint radiation-induced micronuclei (MN) in three lymphoblastoid cells lines to investigate the frequency of radiation-induced MN. The results obtained for four different chromosomes showed that there was a significant deviation of the numbers of signal-positive MN from that expected on the basis of DNA proportionality. Restriction of the analysis to three chromosomes showed that the deviations arose primarily from chromosome 7, which was underrepresented in the numbers of signal-positive MN in the group of chromosomes studied.


Assuntos
Cromossomos Humanos/efeitos da radiação , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Citocalasina B/farmacologia , Citogenética/métodos , Fluoresceína-5-Isotiocianato , Humanos , Hibridização In Situ , Cariotipagem , Linfócitos/efeitos da radiação , Linfócitos/ultraestrutura
10.
Environ Toxicol ; 16(4): 321-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11501281

RESUMO

Screening methods to indicate the genotoxic potential of individual chemicals or environmental mixtures rely mainly on short-term bacterial tests. Differences in the genotoxic response of prokaryotic and eukaryotic cells necessitate the development of nonbacterial screening assays. A promising approach for this purpose could be the comet (single-cell gel electrophoresis) assay performed with fish cells in vitro. In the present study, we evaluated the comet assay with two different fish cell lines from rainbow trout (Oncorhyhnchus mykiss), the fibroblast-like RTG-2 cell line established from gonad tissue, and the epitheloid RTL-W1 cell line established from liver tissue. The cells were exposed in vitro during 2 hr to the genotoxins, 4-nitroquinoline-1-oxide (NQO), and benzo(a)pyrene (BaP), as well as to environmental samples. The LOEC values for NQO were similar in both cell lines, whereas for BaP, the RTL-W1 cells were found to be more sensitive than the RTG-2 cells. The slopes of the concentration-response curves of the two test compounds differed between the two cell lines, with RTG-2 cells showing a steeper slope for NQO, and RTL-W1 cells showing a steeper slope for BaP. When exposed to environmental samples from a remediation site, the RTL-W1 cell line, but not the RTG-2 cell line, indicated a genotoxic potential of the samples. The differences in the genotoxic response pattern of the two cell lines could be only partly explained in relation to metabolic enzymes, cytochrome P4501A, glutathione-S-transferase, and xenobiotic reductase. The findings of this study demonstrate that the comet assay with fish cell lines is suitable as in vitro screening assay in environmental genotoxicity testing, but the choice of test cell line may be critical.


Assuntos
Ensaio Cometa/métodos , Dano ao DNA , Poluentes Ambientais/efeitos adversos , Oncorhynchus mykiss/genética , Animais , Linhagem Celular , Gônadas/citologia , Fígado/citologia , Mutagênicos/efeitos adversos , Oncorhynchus mykiss/fisiologia , Sensibilidade e Especificidade
11.
Ecotoxicol Environ Saf ; 51(2): 145-53, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11886188

RESUMO

The response of wild fish to pollutants was studied using two biomarkers in chub (Leuciscus cephalus) at five stations in the Moselle River (France) in 1998 and in 1999. The induction of cytochrome P450 1A was quantified by the ethoxyresorufin O-deethylase (EROD) activity in the liver and the level of DNA single-strand breaks was determined in erythrocytes using the comet assay. EROD activity was observed to be up to 10-fold induced in both males and females from the downstream stations in comparison to the fish from the upstream station. Levels of DNA damage did not parallel EROD induction. Chemical analyses did not clearly explain the responses of the studied biomarkers, confirming the great difficulty in relating chemical and biological information in the field. This study confirms the difficulty in assessing the biological effects of mixtures of pollutants and points out the usefulness of a large array of biomarkers.


Assuntos
Cyprinidae/genética , Cyprinidae/metabolismo , Citocromo P-450 CYP1A1/biossíntese , Dano ao DNA , Eritrócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores , Ensaio Cometa , Cyprinidae/crescimento & desenvolvimento , Eritrócitos/ultraestrutura , Feminino , França , Fígado/enzimologia , Masculino , Músculos/química , Poluentes Químicos da Água/farmacocinética
12.
Mutagenesis ; 12(2): 91-5, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9106249

RESUMO

In situ hybridization with whole chromosome painting probes (chromosome 1, 7, 11, 14, 17 and 21) in combination with a human pancentromeric alpha-satellite probe was used to analyse the presence of specific chromosomal material in micronuclei (MN) induced in human lymphocytes by ionizing radiation. The purpose was to investigate the nature of radiation-induced cytogenetic damage, especially to study whether the fraction of paint-positive MN is proportional to the relative DNA content of the respective chromosomes which might indicate a random breakage of chromosomes. Flow-sorted MN and MN in binucleated cells were analysed with the six chromosome specific painting probes. It was found that the fraction of paint-positive MN increased linearly with the DNA content of the respective chromosomes. About 13% radiation-induced MN in human lymphocytes were found to contain centromeric signals independent of the presence of specific chromosome painting signals. The data obtained on flow-sorted MN and MN in binucleated cells agreed well, indicating that flow-sorted MN can be used for studying their chromosomal content with the FISH technique. If it is assumed that the chromosomal content of MN reflects radiation-induced damage, then these results support a random model of radiation-induced cytogenetic damage in human lymphocytes for the six chromosomes studied.


Assuntos
Núcleo Celular/efeitos da radiação , Centrômero/genética , Sondas de DNA , Hibridização in Situ Fluorescente/métodos , Testes para Micronúcleos/métodos , Adulto , Bandeamento Cromossômico/métodos , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 21 , Cromossomos Humanos Par 7 , Humanos
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