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21.
Marilyne Labrie Nicholas D Kendsersky Hongli Ma Lydia Campbell Jennifer Eng Koei Chin 《Expert review of proteomics》2013,10(10):841-850
ABSTRACTIntroduction: Due to the relatively low mutation rate and high frequency of copy number variation, finding actionable genetic drivers of high-grade serous carcinoma (HGSC) is a challenging task. Furthermore, emerging studies show that genetic alterations are frequently poorly represented at the protein level adding a layer of complexity. With improvements in large-scale proteomic technologies, proteomics studies have the potential to provide robust analysis of the pathways driving high HGSC behavior.Areas covered: This review summarizes recent large-scale proteomics findings across adequately sized ovarian cancer sample sets. Key words combined with ‘ovarian cancer’ including ‘proteomics’, ‘proteogenomic’, ‘reverse-phase protein array’, ‘mass spectrometry’, and ‘adaptive response’, were used to search PubMed.Expert opinion: Proteomics analysis of HGSC as well as their adaptive responses to therapy can uncover new therapeutic liabilities, which can reduce the emergence of drug resistance and potentially improve patient outcomes. There is a pressing need to better understand how the genomic and epigenomic heterogeneity intrinsic to ovarian cancer is reflected at the protein level and how this information could be used to improve patient outcomes. 相似文献
22.
The first overview on the Auchenorrhyncha fauna of peat bogs of the Austrian Bohemian Forest is presented. Seven oligotrophic peat bog sites were studied in 2011 by suction sampler (“G-Vac”) and 93 Auchenorrhyncha species (with 7465 adult specimens) were recorded. Eleven species (about 18 % of the individuals) are tyrphobiontic or tyrphophilous. The relative species abundance plot is not very steep; the six most abundant species represent 50 % of the individuals. The most common species is Conomelus anceps (17 % of the individuals). Compared to the whole Austrian Auchenorrhyncha fauna, the fauna of peat bogs comprises distinctly more univoltine species and more species hibernating in nymphal stage. Densities of adult Auchenorrhyncha in peat bogs are low in spring (about 10–60 individuals per m²) and high in July, with up to 180 (±50) individuals per m². Disturbed peat bogs have higher species numbers and higher Auchenorrhyncha densities in total, but lower numbers and densities in peat bog specialists. 相似文献
23.
Shevin T. Jacob Patricia B. Pavlinac Lydia Nakiyingi Patrick Banura Jared M. Baeten Karen Morgan Amalia Magaret Yuka Manabe Steven J. Reynolds W. Conrad Liles Anna Wald Moses L. Joloba Harriet Mayanja-Kizza W. Michael Scheld 《PloS one》2013,8(8)
Background
When manifested as Mycobacterium tuberculosis (MTB) bacteremia, disseminated MTB infection clinically mimics other serious blood stream infections often hindering early diagnosis and initiation of potentially life-saving anti-tuberculosis therapy. In a cohort of hospitalized HIV-infected Ugandan patients with severe sepsis, we report the frequency, management and outcomes of patients with MTB bacteremia and propose a risk score based on clinical predictors of MTB bacteremia.Methods
We prospectively enrolled adult patients with severe sepsis at two Ugandan hospitals and obtained blood cultures for MTB identification. Multivariable logistic regression modeling was used to determine predictors of MTB bacteremia and to inform the stratification of patients into MTB bacteremia risk categories based on relevant patient characteristics.Results
Among 368 HIV-infected patients with a syndrome of severe sepsis, eighty-six (23%) had MTB bacteremia. Patients with MTB bacteremia had a significantly lower median CD4 count (17 vs 64 lymphocytes/mm3, p<0.001) and a higher 30-day mortality (53% vs 32%, p = 0.001) than patients without MTB bacteremia. A minority of patients with MTB bacteremia underwent standard MTB diagnostic testing (24%) or received empiric anti-tuberculosis therapy (15%). Independent factors associated with MTB bacteremia included male sex, increased heart rate, low CD4 count, absence of highly active anti-retroviral therapy, chief complaint of fever, low serum sodium and low hemoglobin. A risk score derived from a model containing these independent predictors had good predictive accuracy [area under the curve = 0.85, 95% CI 0.80–0.89].Conclusions
Nearly 1 in 4 adult HIV-infected patients hospitalized with severe sepsis in 2 Ugandan hospitals had MTB bacteremia. Among patients in whom MTB was suspected, standard tests for diagnosing pulmonary MTB were inaccurate for correctly classifying patients with or without bloodstream MTB infection. A MTB bacteremia risk score can improve early diagnosis of MTB bacteremia particularly in settings with increased HIV and MTB co-infection. 相似文献24.
Lesia Dmytrenko Michal Cicanic Miroslava Anderova Ivan Vorisek Ole Petter Ottersen Eva Sykova Lydia Vargova 《PloS one》2013,8(7)
Aquaporin-4 (AQP4) is the primary cellular water channel in the brain and is abundantly expressed by astrocytes along the blood-brain barrier and brain-cerebrospinal fluid interfaces. Water transport via AQP4 contributes to the activity-dependent volume changes of the extracellular space (ECS), which affect extracellular solute concentrations and neuronal excitability. AQP4 is anchored by α-syntrophin (α-syn), the deletion of which leads to reduced AQP4 levels in perivascular and subpial membranes. We used the real-time iontophoretic method and/or diffusion-weighted magnetic resonance imaging to clarify the impact of α-syn deletion on astrocyte morphology and changes in extracellular diffusion associated with cell swelling in vitro and in vivo. In mice lacking α-syn, we found higher resting values of the apparent diffusion coefficient of water (ADCW) and the extracellular volume fraction (α). No significant differences in tortuosity (λ) or non-specific uptake (k′), were found between α-syn-negative (α-syn −/−) and α-syn-positive (α-syn +/+) mice. The deletion of α-syn resulted in a significantly smaller relative decrease in α observed during elevated K+ (10 mM) and severe hypotonic stress (−100 mOsmol/l), but not during mild hypotonic stress (−50 mOsmol/l). After the induction of terminal ischemia/anoxia, the final values of ADCW as well as of the ECS volume fraction α indicate milder cell swelling in α-syn −/− in comparison with α-syn +/+ mice. Shortly after terminal ischemia/anoxia induction, the onset of a steep rise in the extracellular potassium concentration and an increase in λ was faster in α-syn −/− mice, but the final values did not differ between α-syn −/− and α-syn +/+ mice. This study reveals that water transport through AQP4 channels enhances and accelerates astrocyte swelling. The substantially altered ECS diffusion parameters will likely affect the movement of neuroactive substances and/or trophic factors, which in turn may modulate the extent of tissue damage and/or drug distribution. 相似文献
25.
Xavier Waltz Marc Romana Marie-Dominique Hardy-Dessources Yann Lamarre Lydia Divialle-Doumdo Marie Petras Vanessa Tarer Régine Hierso Kizzy-Clara Baltyde Beno?t Tressières Marie-Laure Lalanne-Mistrih Fréderic Maillard Olivier Hue Maryse Etienne-Julan Philippe Connes 《PloS one》2013,8(10)
The six-minute walk test is a well-established submaximal exercise reflecting the functional status and the clinical severity of sickle cell patients. The aim of the present cross-sectional study was to investigate the biological determinants of the six-minute walk test performance in children with sickle cell anemia. Hematological and hemorheological parameters, pulmonary function and the six-minute walk test performance were determined in 42 children with sickle cell anemia at steady state. The performance during the six-minute walk test was normalized for age, sex and height and expressed as percentage of the predicted six-minute walk distance. We showed that a high level of anemia, a low fetal hemoglobin expression and low red blood cell deformability were independent predictors of a low six-minute walk test performance. This study describes for the first time the impact of blood rheology in the six-minute walk test performance in children with sickle cell anemia. 相似文献
26.
Mariela Chertoff Kalpana Shrivastava Berta Gonzalez Laia Acarin Lydia Giménez-Llort 《PloS one》2013,8(8)
During postnatal development, microglia, the resident innate immune cells of the central nervous system are constantly monitoring the brain parenchyma, cleaning the cell debris, the synaptic contacts overproduced and also maintaining the brain homeostasis. In this context, the postnatal microglia need some control over the innate immune response. One such molecule recently described to be involved in modulation of immune response is TREM2 (triggering receptor expressed on myeloid cells 2). Although some studies have observed TREM2 mRNA in postnatal brain, the regional pattern of the TREM2 protein has not been described. We therefore characterized the distribution of TREM2 protein in mice brain from Postnatal day (P) 1 to 14 by immunostaining. In our study, TREM2 protein was expressed only in microglia/macrophages and is developmentally downregulated in a region-dependent manner. Its expression persisted in white matter, mainly in caudal corpus callosum, and the neurogenic subventricular zone for a longer time than in grey matter. Additionally, the phenotypes of the TREM2+ microglia also differ; expressing CD16/32, MHCII and CD86 (antigen presentation markers) and CD68 (phagocytic marker) in different regions as well as with different intensity till P7. The mannose receptor (CD206) colocalized with TREM2 only at P1–P3 in the subventricular zone and cingulum, while others persisted at low intensities till P7. Furthermore, the spatiotemporal expression pattern and characterization of TREM2 indicate towards its other plausible roles in phagocytosis, progenitor’s fate determination or microglia phenotype modulation during postnatal development. Hence, the increase of TREM2 observed in pathologies may recapitulate their function during postnatal development, as a better understanding of this period may open new pathway for future therapies. 相似文献
27.
Schllnberger Helmut Kaiser Jan Christian Eidemller Markus Zablotska Lydia B. 《Radiation and environmental biophysics》2020,59(1):63-78
Radiation and Environmental Biophysics - Recent analyses of the Canadian fluoroscopy cohort study reported significantly increased radiation risks of mortality from ischemic heart diseases (IHD)... 相似文献
28.
29.
Derya Akkaynak Justine J. Allen Lydia M. Mäthger Chuan-Chin Chiao Roger T. Hanlon 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2013,199(3):211-225
Cephalopods are renowned for their ability to adaptively camouflage on diverse backgrounds. Sepia officinalis camouflage body patterns have been characterized spectrally in the laboratory but not in the field due to the challenges of dynamic natural light fields and the difficulty of using spectrophotometric instruments underwater. To assess cuttlefish color match in their natural habitats, we studied the spectral properties of S. officinalis and their backgrounds on the Aegean coast of Turkey using point-by-point in situ spectrometry. Fifteen spectrometry datasets were collected from seven cuttlefish; radiance spectra from animal body components and surrounding substrates were measured at depths shallower than 5 m. We quantified luminance and color contrast of cuttlefish components and background substrates in the eyes of hypothetical di- and trichromatic fish predators. Additionally, we converted radiance spectra to sRGB color space to simulate their in situ appearance to a human observer. Within the range of natural colors at our study site, cuttlefish closely matched the substrate spectra in a variety of body patterns. Theoretical calculations showed that this effect might be more pronounced at greater depths. We also showed that a non-biological method (“Spectral Angle Mapper”), commonly used for spectral shape similarity assessment in the field of remote sensing, shows moderate correlation to biological measures of color contrast. This performance is comparable to that of a traditional measure of spectral shape similarity, hue and chroma. This study is among the first to quantify color matching of camouflaged cuttlefish in the wild. 相似文献
30.