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1.
BMC Anesthesiol ; 22(1): 35, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35105307

RESUMEN

BACKGROUND: Sterile water injections can provide effective pain relief during childbirth, particularly for low back pain related to childbirth. However, the pain associated administering the injections can negatively impact women's impressions of the procedure. It may discourage women from considering repeat doses despite the quality of analgesia experienced. Determining strategies to reduce the pain related to the administration of sterile water injections would improve the acceptability of the technique. Therefore, the aim of this study was to evaluate the effect of topical local anesthesia on the pain associated with administration of sterile water injections. METHODS: The study was designed as a multi-arm single-blind, randomized, controlled trial and 120 female healthy students were randomly divided according to one of four groups. The Intervention group received sterile water injections with topical local anesthesia. Control group 1 received sterile water injections without topical local anesthesia, control group 2 received injections of isotonic saline 0.9% with topical local anesthesia and control group 3 received injections of isotonic saline 0.9% without topical local anesthesia. Pain Immediately after the injections and subsidence in pain were recorded using a visual analogue scale. Sensations in the injection area were reported 15 min and the day after the injections. RESULTS: The main finding of this study was that local anesthesia with EMLA® reduces the pain associated with the administration of intracutaneous sterile water injections. There was a significant difference in the self-assessed pain score immediately following the injections between the control (73.3 mm) and intervention groups (50.0 mm), p = 0.001. No adverse side effects were reported. CONCLUSION: Local anesthesia with EMLA® reduces the pain associated with intracutaneous administration of sterile water injections. TRIAL REGISTRATION: The study was registered 08/07/2014 at ClinicalTrials.gov Identifier: NCT02213185 .


Asunto(s)
Anestesia Local/métodos , Anestésicos Locales/uso terapéutico , Dolor/prevención & control , Agua/administración & dosificación , Administración Tópica , Adulto , Anestésicos Locales/administración & dosificación , Femenino , Humanos , Inyecciones Intradérmicas/efectos adversos , Manejo del Dolor/métodos , Método Simple Ciego , Resultado del Tratamiento , Adulto Joven
2.
Mol Biol Rep ; 48(3): 2429-2436, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33761087

RESUMEN

Prostate cancer (PCa) is a highly heterogeneous and unpredictable progressive disease. Sensitivity of PCa cells to androgens play a central role in tumor aggressiveness but biomarkers with high sensitivity and specificity that follow the progression of the disease has not yet been verified. The vitamin D endocrine system and its receptors, the Vitamin D Receptor (VDR) and the Protein Disulfide-Isomerase A3 (PDIA3), are related to anti-tumoral effects as well as carcinogenesis and have therefore been suggested as potential candidates for the prevention and therapy of several cancer forms, including PCa. In this study, we evaluated the mRNA expression of VDR and PDIA3 involved in vitamin D signaling in cell lines representing different stages of PCa (PNT2, P4E6, LNCaP, DU145 and PC3). This study further aimed to evaluate vitamin D receptors and their isoforms as potential markers for clinical diagnosis of PCa. A novel transcript isoform of PDIA3 (PDIA3N) was identified and found to be expressed in all PCa cell lines analyzed. Androgen-independent cell lines showed a higher mRNA expression ratio between PDIA3N/PDIA3 contrary to androgen-dependent cell lines that showed a lower mRNA expression ratio between PDIA3N/PDIA3. The structure of PDIA3N differed from PDIA3. PDIA3N was found to be a N-truncated isoform of PDIA3 and differences in protein structure suggests an altered protein function i.e. cell location, thioredoxin activity and affinity for 1,25(OH)2D3. Collectively, PDIA3 transcript isoforms, the ratio between PDIA3N/PDIA3 and especially PDIA3N, are proposed as candidate markers for future studies with different stages of PCa progression.


Asunto(s)
Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/patología , Proteína Disulfuro Isomerasas/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Línea Celular Tumoral , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Estadificación de Neoplasias , Neoplasias de la Próstata/genética , Proteína Disulfuro Isomerasas/química , Proteína Disulfuro Isomerasas/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo
3.
Proc Natl Acad Sci U S A ; 113(33): 9177-81, 2016 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-27482118

RESUMEN

The spontaneous appearance of nematicity, a state of matter that breaks rotation but not translation symmetry, is one of the most intriguing properties of the iron-based superconductors (Fe SC), and has relevance for the cuprates as well. Establishing the critical electronic modes behind nematicity remains a challenge, however, because their associated susceptibilities are not easily accessible by conventional probes. Here, using FeSe as a model system, and symmetry-resolved electronic Raman scattering as a probe, we unravel the presence of critical charge nematic fluctuations near the structural/nematic transition temperature, [Formula: see text] 90 K. The diverging behavior of the associated nematic susceptibility foretells the presence of a Pomeranchuk instability of the Fermi surface with d-wave symmetry. The excellent scaling between the observed nematic susceptibility and elastic modulus data demonstrates that the structural distortion is driven by this d-wave Pomeranchuk transition. Our results make a strong case for charge-induced nematicity in FeSe.

4.
Phys Rev Lett ; 121(7): 077001, 2018 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-30169100

RESUMEN

We report the evolution of the electronic nematic susceptibility in FeSe via Raman scattering as a function of hydrostatic pressure up to 5.8 GPa where the superconducting transition temperature T_{c} reaches its maximum. The critical nematic fluctuations observed at low pressure vanish above 1.6 GPa, indicating they play a marginal role in the fourfold enhancement of T_{c} at higher pressures. The collapse of nematic fluctuations appears to be linked to a suppression of low energy electronic excitations which manifests itself by optical phonon anomalies at around 2 GPa, in agreement with lattice dynamical and electronic structure calculations using local density approximation combined with dynamical mean field theory. Our results reveal two different regimes of nematicity in the phase diagram of FeSe under pressure: a d-wave Pomeranchuk instability of the Fermi surface at low pressure and a magnetic driven orthorhombic distortion at higher pressure.

5.
BMC Genet ; 16: 80, 2015 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-26170120

RESUMEN

BACKGROUND: Several reports indicate a commonly deleted chromosomal region independent from, and distal to the TP53 locus in a variety of human tumors. In a previous study, we reported a similar finding in a rat tumor model for endometrial carcinoma (EC) and through developing a deletion map, narrowed the candidate region to 700 kb, harboring 19 genes. In the present work real-time qPCR analysis, Western blot, semi-quantitative qPCR, sequencing, promoter methylation analysis, and epigenetic gene expression restoration analyses (5-aza-2'-deoxycytidine and/or trichostatin A treatments) were used to analyze the 19 genes located within the candidate region in a panel of experimental tumors compared to control samples. RESULTS: Real-time qPCR analysis suggested Hic1 (hypermethylated in cancer 1), Inpp5k (inositol polyphosphate-5-phosphatase K; a.k.a. Skip, skeletal muscle and kidney enriched inositol phosphatase) and Myo1c (myosin 1c) as the best targets for the observed deletions. No mutation in coding sequences of these genes was detected, hence the observed low expression levels suggest a haploinsufficient mode of function for these potential tumor suppressor genes. Both Inpp5k and Myo1c were down regulated at mRNA and/or protein levels, which could be rescued in gene expression restoration assays. This could not be shown for Hic1. CONCLUSION: Innp5k and Myo1c were identified as the best targets for the deletions in the region. INPP5K and MYO1C are located adjacent to each other within the reported independent region of tumor suppressor activity located at chromosome arm 17p distal to TP53 in human tumors. There is no earlier report on the potential tumor suppressor activity of INPP5K and MYO1C, however, overlapping roles in phosphoinositide (PI) 3-kinase/Akt signaling, known to be vital for the cell growth and survival, are reported for both. Moreover, there are reports on tumor suppressor activity of other members of the gene families that INPP5K and MYO1C belong to. Functional significance of these two candidate tumor suppressor genes in cancerogenesis pathways remains to be investigated.


Asunto(s)
Genes Supresores de Tumor , Sitios Genéticos , Miosina Tipo I/genética , Monoéster Fosfórico Hidrolasas/genética , Proteína p53 Supresora de Tumor/genética , Animales , Azacitidina/farmacología , Metilación de ADN , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Ácidos Hidroxámicos/farmacología , Inositol Polifosfato 5-Fosfatasas , Ratas
6.
J Matern Fetal Neonatal Med ; 35(25): 8521-8529, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34696678

RESUMEN

INTRODUCTION: Obesity is a globally growing problem. Labor dystocia is associated with obstetric complications, especially among obese pregnant women. Previous studies have shown an association between the level of lactate produced by uterine myocytes during contractions and the level of lactate in the amniotic fluid (AFL). A relationship between a high level of AFL and labor dystocia has also been demonstrated. However, it is still unknown whether the observation applies to all women with labor dystocia, regardless of body mass index (BMI). Aims: This study investigated whether there was any difference in the level of AFL in the three BMI groups and whether there was a difference in labor outcomes between high and low AFL in the different groups. MATERIALS AND METHODS: This cross-sectional study included 1683 women from three different countries. Healthy nulliparous women in active labor were included, and they were grouped according to BMI as normal weighted (<25), overweight (≥25-29), and obese (≥30), respectively. AFL was categorized as high (≥10.1 mmol/l) and low (<10.1 mmol/l). The main outcome was the frequency of cesarean section. RESULTS: No difference in AFL levels was found between the three BMI groups at delivery (mean values of 8.2 vs. 8.3 vs. 8.4 mmol/l, p = .3). Obese women with high AFL had a higher frequency of cesarean section than normal-weighted women (16.2 vs. 20.7 vs. 29.2%). Other risk factors associated with cesarean section varied among the different BMI groups. CONCLUSIONS: This study showed no difference in the mean level of AFL between women with different BMIs. Further, high AFL was associated with a higher frequency of cesarean section in all three BMI groups, suggesting that the level of AFL can in the future be used as a predictor of labor outcome among women with labor dystocia despite their BMI.


Asunto(s)
Cesárea , Distocia , Femenino , Embarazo , Humanos , Índice de Masa Corporal , Estudios Transversales , Líquido Amniótico , Ácido Láctico , Distocia/epidemiología , Obesidad/complicaciones , Obesidad/epidemiología
7.
Sci Rep ; 12(1): 12670, 2022 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-35879377

RESUMEN

Numerous studies have shown that lifestyle factors, such as regular physical activity and vitamin D intake, may remarkably improve overall health and mental wellbeing. This is especially important in older adults whose vitamin D deficiency occurs with a high prevalence. This study aimed to examine the influence of lifestyle and vitamin D on global DNA methylation patterns in an elderly cohort in Southwest of Sweden. We also sought to examine the methylation levels of specific genes involved in vitamin D's molecular and metabolic activated pathways. We performed a genome wide methylation analysis, using Illumina Infinium DNA Methylation EPIC 850kBeadChip array, on 277 healthy individuals from Southwest Sweden at the age of 70-95. The study participants also answered queries on lifestyle, vitamin intake, heart medication, and estimated health. Vitamin D intake did not in general affect methylation patterns, which is in concert with other studies. However, when comparing the group of individuals taking vitamin supplements, including vitamin D, with those not taking supplements, a difference in methylation in the solute carrier family 25 (SCL25A24) gene was found. This confirms a previous finding, where changes in expression of SLC25A24 were associated with vitamin D treatment in human monocytes. The combination of vitamin D intake and high physical activity increased methylation of genes linked to regulation of vitamin D receptor pathway, the Wnt pathway and general cancer processes. To our knowledge, this is the first study detecting epigenetic markers associated with the combined effects of vitamin D supplementation and high physical activity. These results deserve to be further investigated in an extended, interventional study cohort, where also the levels of 25(OH)D3 can be monitored.


Asunto(s)
Deficiencia de Vitamina D , Anciano , Metilación de ADN , Suplementos Dietéticos , Humanos , Estilo de Vida , Suecia/epidemiología , Vitamina D/metabolismo , Deficiencia de Vitamina D/genética , Vitaminas/farmacología , Vitaminas/uso terapéutico
8.
Contemp Clin Trials Commun ; 21: 100687, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33385096

RESUMEN

BACKGROUND: Aging often involves health problems and difficulties, such as physical and psychological impairments, isolation, and loneliness, causing social and existential consequences. Studies have explored aging from different perspectives. However, few studies have examined healthy older adults' genetic backgrounds, lifestyles, and meaning in life separately or in combination. This study aims to describe how healthy older adults experience aging, health, lifestyles, and meaning in life and explore potential genetic correlations. METHODS AND DESIGN: The project will comprise three main parts: a quantitative section featuring the development and testing of a lifestyle questionnaire, a quantitative genetic analysis, and a qualitative interview study. Participants will be community-dwelling, healthy, older adults between 70 and 95 years of age. A sample size of 800 older adults will be invited to participate in seminars in collaboration with the national Swedish association Active Seniors. Data will be collected through lifestyle questionnaire, DNA extracted from saliva samples, and interviews. Based on questionnaire responses, profile groups will be created and compared statistically with variations in genetic backgrounds, providing the basis for recruiting participants to the qualitative interviews. DISCUSSION: This study's expected outcome will be to gain knowledge about variations in genetic backgrounds correlated with individual experiences regarding aging, health, and meaning in life. This knowledge can improve the understanding of motivations for healthy lifestyle changes. The results can reveal potential implications for individual prerequisites to healthy aging and how health-promoting aging and lifestyle counseling can be adjusted to meet individual needs.

9.
Anticancer Res ; 41(10): 4733-4740, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34593422

RESUMEN

BACKGROUND/AIM: Growing evidence suggests that vitamin D3 exerts anticancer effects. The present study aimed to evaluate 25-hydroxyvitamin D3 (25(OH)D3) as a potential endocrine factor regulating proliferation and vitamin D receptor expression in LNCaP prostate cancer cells. MATERIALS AND METHODS: Cell counting after treatment was utilized to assess the effect of 25(OH)D3 on cell proliferation. Changes in mRNA expression of the vitamin D receptors, VDR and PDIA3, were evaluated using droplet digital polymerase chain reaction (ddPCR). RESULTS: 25(OH)D3 inhibited cell proliferation in a dose- and time-dependent manner. The inhibitory effect of 25(OH)D3 on cell proliferation was potentiated after inhibition of CYP17B1 and CYP24 by genistein, preventing further metabolism of 25(OH)D3 to 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) and 24,25-dihydroxyvitamin D3 (24,25(OH)2D3). Expression of PDIA3 and VDR mRNA increased after treatment with 25(OH)D3, whereas the ratio between PDIA3 and VDR mRNA remained unchanged. CONCLUSION: 25(OH)D3 has a direct inhibitory effect on cell proliferation, which is enhanced and accelerated when the metabolism of 25(OH)D3 to 1,25(OH)2D3 and 24,25(OH)2D3 was inhibited by the CYP17B1 and CYP24 inhibitor genistein. Furthermore, treatment with 25(OH)D3 increased receptor transcript expression, suggesting an increased VDR stability and sensibility of the treated cells.


Asunto(s)
25-Hidroxivitamina D3 1-alfa-Hidroxilasa/antagonistas & inhibidores , Calcifediol/farmacología , Proliferación Celular/efectos de los fármacos , Vitamina D3 24-Hidroxilasa/antagonistas & inhibidores , Línea Celular Tumoral , Genisteína/farmacología , Humanos , Masculino , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Proteína Disulfuro Isomerasas/genética , ARN Mensajero , Receptores de Calcitriol/genética
10.
Open Med (Wars) ; 16(1): 640-650, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33954257

RESUMEN

Nuclear receptors (NRs) are ligand-activated transcription factors that regulate gene expression when bound to specific DNA sequences. Crosstalk between steroid NR systems has been studied for understanding the development of hormone-driven cancers but not to an extent at a genetic level. This study aimed to investigate crosstalk between steroid NRs in conserved intron and exon sequences, with a focus on steroid NRs involved in prostate cancer etiology. For this purpose, we evaluated conserved intron and exon sequences among all 49 members of the NR Superfamily (NRS) and their relevance as regulatory sequences and NR-binding sequences. Sequence conservation was found to be higher in the first intron (35%), when compared with downstream introns. Seventy-nine percent of the conserved regions in the NRS contained putative transcription factor binding sites (TFBS) and a large fraction of these sequences contained splicing sites (SS). Analysis of transcription factors binding to putative intronic and exonic TFBS revealed that 5 and 16%, respectively, were NRs. The present study suggests crosstalk between steroid NRs, e.g., vitamin D, estrogen, progesterone, and retinoic acid endocrine systems, through cis-regulatory elements in conserved sequences of introns and exons. This investigation gives evidence for crosstalk between steroid hormones and contributes to novel targets for steroid NR regulation.

11.
Cancer Cell Int ; 10: 46, 2010 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-21106063

RESUMEN

Glutathione peroxidase 3 (GPX3) is one of the key enzymes in the cellular defense against oxidative stress and the hepatocyte growth factor receptor, (MET) has been suggested to be influenced by the GPX3 gene expression. In a previous microarray study performed by our group, Gpx3 was identified as a potential biomarker for rat endometrial adenocarcinoma (EAC), since the expression was highly downregulated in rat EAC tumors. Herein, we have investigated the mRNA expression and Gpx3 and Met in rat EAC by real time quantitative PCR (qPCR), and the methylation status of Gpx3. In addition we have examined the expression of GPX3 and MET in 30 human EACs of different FIGO grades and 20 benign endometrial tissues. We found that the expression of GPX3 was uniformly down regulated in both rat and human EAC, regardless of tumor grade or histopathological subtype, implying that the down-regulation is an early event in EAC. The rate of Gpx3 promoter methylation reaches 91%, where biallelic methylation was present in 90% of the methylated tumors. The expression of the Met oncogene was slightly upregulated in EACs that showed loss of expression of Gpx3, but no tumor suppressor activity of Gpx3/GPX3 was detected. Preliminary results also suggest that the production of H2O2 is higher in rat endometrial tumors with down-regulated Gpx3 expression. A likely consequence of loss of GPX3 protein function would be a higher amount of ROS in the cancer cell environment. Thus, the results suggest important clinical implications of the GPX3 expression in EAC, both as a molecular biomarker for EAC and as a potential target for therapeutic interventions.

12.
Cancer Cell Int ; 9: 12, 2009 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-19426485

RESUMEN

BACKGROUND: In the Western world, endometrial cancers are the most common gynaecological neoplastic disorders among women. Initial symptoms are often vague and may be confused with several other conditions or disorders. Thus, there is a need for an easy and reliable diagnostic tool. The objective of this work was to identify a gene expression signature specific for endometrial adenocarcinomas to be used for testing potential endometrial biomarkers. RESULTS: Changes in expression between endometrial adenocarcinomas and non-/pre-malignant endometrium from the BDII EAC rat model were compared in cDNA microarray assays. By employing classification analysis (Weka) on the expression data from approximately 5600 cDNA clones and TDT analysis on genotype data, we identified a three-gene signature (Gpx3, Bgn and Tgfb3). An independent analysis of differential expression, revealed a total of 354 cDNA clones with significant changes in expression. Among the 10 best ranked clones, Gpx3, Bgn and Tgfb3 were found. CONCLUSION: Taken together, we present a unique data set of genes with different expression patterns between EACs and non-/pre-malignant endometrium, and specifically we found three genes that were confirmed in two independent analyses. These three genes are candidates for an EAC signature and further evaluations of their involvement in EAC tumorigenesis will be undertaken.

13.
Adv Exp Med Biol ; 617: 503-9, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18497075

RESUMEN

Endometrial cancer (EC) is the most abundant female gynaecologic malignancy, ranking fourth in incidence among invasive tumors in women. Hormone-related (estrogen-dependent) EC is the prevalent subtype and accounts for approximately 75% of these cancers. Females of the BDII inbred rat strain are extremely prone to endometrial adenocarcinoma, (EAC) and approximately 90% of virgin females spontaneously develop EAC during their life span. Thus, these rats serve as a useful model for the genetic analysis of this malignancy. In the present work, gene expression profiling, by means of cDNA microarrays, was performed on cDNA from endometrial tumor cell lines and from cell lines derived from nonmalignant lesions/normal tissues of the endometrium without specific findings (WSF). We identified numerous genes differentially expressed between endometrial cell lines and WSFs employing clustering analysis and statistical inference analysis. Many of the genes identified are located within or close to the chromosomal regions earlier identified to be associated with EAC susceptibility and development. Several of the genes identified are involved in pathways commonly altered in carcinogenesis, such as the TGF-pathway.


Asunto(s)
Adenocarcinoma/genética , Biomarcadores de Tumor/genética , Modelos Animales de Enfermedad , Neoplasias Endometriales/genética , Regulación Neoplásica de la Expresión Génica/fisiología , Adenocarcinoma/patología , Animales , Neoplasias Endometriales/patología , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos , Ratas , Ratas Endogámicas BN , Ratas Sprague-Dawley , Células Tumorales Cultivadas
14.
Cancer Genet Cytogenet ; 177(1): 43-50, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17693190

RESUMEN

Endometrial cancer is the most abundant female gynecologic malignancy, ranking fourth in incidence among invasive tumors in women. Females of the BDII inbred rat strain are extremely prone to endometrial adenocarcinoma (EAC), and approximately 90% of virgin females spontaneously develop EAC during their lifetime. Thus, these rats serve as a useful model for the genetic analysis of this malignancy. In the present work, gene expression profiling, by means of cDNA microarrays, was performed on cDNA from endometrial tumor cell lines and from cell lines derived from nonmalignant lesions/normal tissues of the endometrium. We identified several genes associated with the transforming growth factor-beta (TGF-beta) pathway to be differentially expressed between endometrial tumor cell lines and nonmalignant lesions by using clustering and statistical inference analyses. The expression levels of the genes involved in the TGF-beta pathway were independently verified using semiquantitative reverse-transcription polymerase chain reaction. Repressed TGF-beta signaling has been reported previously in EAC carcinogenesis, but this is the first report demonstrating aberrations in the expression of TGF-beta downstream target genes. We propose that the irregularities present in TGF-beta pathway among the majority of the EAC tumor cell lines may affect EAC carcinogenesis.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Endometriales/genética , Regulación Neoplásica de la Expresión Génica , Transducción de Señal , Factor de Crecimiento Transformador beta/genética , Animales , Biomarcadores de Tumor/metabolismo , Neoplasias Endometriales/metabolismo , Neoplasias Endometriales/patología , Endometrio/citología , Endometrio/metabolismo , Femenino , Perfilación de la Expresión Génica , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas
15.
Biosystems ; 80(2): 201-13, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15823419

RESUMEN

Pseudomonas aeruginosa is a gram-negative bacterium that causes serious illnesses, particularly in immunocompromised individuals, often with a fatal outcome. The finding that the acylated homoserine lactone quorum sensing (QS) system controls the production of virulence factors in P. aeruginosa makes this system a possible target for antimicrobial therapy. It has been suggested that an N-(3-oxododecanoyl)-homoserine lactone (3O-C12-HSL) antagonist, a QS blocker (QSB), would interfere efficiently with the quorum sensing system in P. aeruginosa and thus reduce the virulence of this pathogen. In this work, a mathematical model of the QS system in P. aeruginosa has been developed. The model was used to virtually add 3O-C12-HSL antagonists that differed in their affinity for the receptor protein and for their ability to mediate degradation of the receptor. The model suggests that very small differences in these parameters for different 3O-C12-HSL antagonists can greatly affect the success of QSB based inhibition of the QS system in P. aeruginosa. Most importantly, it is proposed that the ability of the 3O-C12-HSL antagonist to mediate degradation of LasR is the core parameter for successful QSB based inhibition of the QS system in P. aeruginosa. Finally, this study demonstrates that QSBs can shift the system to a low steady state, corresponding to an uninduced state and thus, suggests that the use of 3O-C12-HSL antagonists may constitute a promising therapeutic approach against P. aeruginosa involved infections.


Asunto(s)
4-Butirolactona/análogos & derivados , 4-Butirolactona/antagonistas & inhibidores , 4-Butirolactona/química , Antibacterianos/química , Antibacterianos/farmacología , Modelos Biológicos , Modelos Químicos , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/metabolismo , 4-Butirolactona/metabolismo , Supervivencia Celular/efectos de los fármacos , Simulación por Computador , Diseño de Fármacos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
16.
PLoS One ; 8(1): e54650, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23349946

RESUMEN

Birds have excellent spatial acuity and colour vision compared to other vertebrates while spatial contrast sensitivity is relatively poor for unknown reasons. Contrast sensitivity describes the detection of gratings of varying spatial frequency. It is unclear whether bird brightness discrimination between large uniform fields is poor as well. Here we show that budgerigars (Melopsittacus undulatus) need a Michelson contrast of 0.09 to discriminate between large spatially separated achromatic fields in bright light conditions. This is similar to the peak contrast sensitivity of 10.2 (0.098 Michelson contrast) for achromatic grating stimuli established in earlier studies. The brightness discrimination threshold described in Weber fractions is 0.18, which is modest compared to other vertebrates.


Asunto(s)
Visión de Colores/fisiología , Melopsittacus/fisiología , Animales , Sensibilidad de Contraste/fisiología , Luz
17.
J Steroid Biochem Mol Biol ; 121(1-2): 413-6, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20398754

RESUMEN

1,25-Dihydroxyvitamin D3 (1,25(OH)2D3) has been demonstrated to mediate both genomic and non-genomic responses in prostate cancer (CaP) cells. Here, we give an overview of membrane initiated 1,25(OH)2D3 signaling in prostate cancer cell progression. The presence of PDIA3 was investigated and homologous modeling of the putative PDIA3 receptor complex was conducted. Furthermore, the cellular distribution of nVDR was analyzed. We could show that both nVDR and PDIA3 are expressed in the prostate cancer cell lines investigated. The homologous modeling of PDIA3 showed that the receptor complex exists in a trimer formation, which suggests for allosteric activity. Our findings support previous reports and suggest that 1,25(OH)2D3 is an important therapeutic agent in inhibiting prostate cancer progression. Furthermore, our data show that 1,25(OH)2D3 regulate prostate cell biology via multiple pathways and targeting specific pathways for 1,25(OH)2D3 might provide more effective therapies compared to the vitamin D therapies currently clinically tested.


Asunto(s)
Neoplasias de la Próstata/metabolismo , Vitamina D/metabolismo , Sitio Alostérico , Línea Celular Tumoral , Membrana Celular/metabolismo , Progresión de la Enfermedad , Humanos , Inmunohistoquímica/métodos , Masculino , Modelos Moleculares , Modelos Teóricos , Conformación Proteica , Receptores de Calcitriol/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal
18.
Int J Cancer ; 120(7): 1472-81, 2007 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-17245700

RESUMEN

We have recently shown in the BDII rat model of human endometrial adenocarcinoma (EAC), rat chromosome 10 (RNO10) is frequently involved in chromosomal aberrations. In the present study, we investigated the association between RNO10 deletions, allelic imbalance (AI) at RNO10q24 and Tp53 mutation in 27 rat EAC tumors. We detected chromosomal breakage accompanied by loss of proximal and/or gain of distal parts of RNO10 in approximately 2/3 of the tumors. This finding is suggestive of a tumor suppressor activity encoded from the proximal RNO10. Given the fact that Tp53 is located at RNO10q24-q25, we then performed Tp53 mutation analysis. However, we could not find a strong correlation between AI/deletions at RNO10q24 and Tp53 mutation. Instead, the observed patterns for AI, chromosomal breaks and deletions suggest that major selection was directed against a region located close to, but distal of Tp53. In different human malignancies a similar situation of AI at chromosome band 17p13.3 (HSA17p13.3) unassociated with TP53 mutation has been observed. Although RNO10 is largely homologous to HSA17, the conservation with respect to gene order among them is not extensive. We utilized publicly available draft DNA sequences to study intrachromosomal rearrangement during the divergence between HSA17 and RNO10. By using reciprocal comparison of rat and human genome data, we could substantially narrow down the candidate tumor suppressor region in rat from 3 Mb to a chromosomal segment of about 0.5 Mb in size. These results provide scientific groundwork for identification of the putative tumor suppressor gene(s) at 17p13.3 in human tumors.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas de los Mamíferos/genética , Neoplasias Endometriales/genética , Proteína p53 Supresora de Tumor/genética , Adenocarcinoma/genética , Desequilibrio Alélico/genética , Animales , Northern Blotting , Pintura Cromosómica , Femenino , Humanos , Hibridación Fluorescente in Situ , Pérdida de Heterocigocidad , Repeticiones de Microsatélite , Ratas , Ratas Endogámicas
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