131 research outputs found
Endothelial Progenitor Cell-Derived Factors Exert Neuroprotection in Cultured Cortical Neuronal Progenitor Cells.
There is substantial evidence that stem and progenitor cells secrete trophic factors that have potential for repairing injured tissues. We have previously reported that the conditioned medium (CM) obtained from endothelial progenitor cells (EPC) cultures protects striatal neurons against 3-nitropropionic acid-induced toxicity. In the present study we tested the hypothesis that EPC-CM may support cortical neuronal cell function and/or survival. EPC were isolated from the peripheral blood of healthy human donors and cultured in hypoxic conditions (1.5% O2) to stimulate the secretion of growth factors. The supernatant or conditioned medium (EPC-CM) was then collected and used for the various experiments. Primary cultures of cerebral cortex from fetal rat embryonic day 14 were treated with EPC-CM and challenged by glucose and serum deprivation. We observed that EPC-CM treatment significantly increased total cell number and cell viability in the cultures. Similarly, the number of lba1-expressing cells was significantly upregulated by EPC-CM, while western blot analyses for the astroglial marker glial fibrillary acidic protein did not show a marked difference. Importantly, the number of beta-lll-tubulin-positive neurons in the cultures was significantly augmented after EPC-CM treatment. Similarly, western blot analyses for beta-III-tubulin showed significant higher signal intensities. Furthermore, EPC-CM administration protected neurons against glucose- and serum deprivation-induced cell loss. In sum, our findings identified EPC-CM as a means to promote viability and/or differentiation of cortical neurons and suggest that EPC-CM might be useful for neurorestorative approaches
Measurements of lower tropospheric ozone at mid-latitudes of the Northern and Southern Hemisphere
Ground-based measurements of ozone have been carried out at three stations in the German alps (47 deg N, 11 deg E, altitudes 740, 1776, and 2962 m a.s.l.) as well as at the coastal station Cape Point (34 deg S, 18 deg E). For the mountain sites (at 1776 and 2962 m), trend calculations based on monthly means have yielded O3 growth rates of 0.8 and 0.9 ppbv yr(exp -1), respectively, over the period 1978-91. Seasonally differentiated data sets have yielded higher rates for summer than for winter. The impact of near-ground photochemical O3 production on the observed O3 concentration is shown. No significant long-term O3 trend has been observed at 740 m (valley floor) as well as at the southern hemispheric station Cape Point. Evidence exists for a close relationship between the amplitude variations of the annual cycles of O3 and CO at Cape Point
On the bound states of the massless free field in two space-time dimensions
We point out the peculiar kinematics of zero-mass fields in two space-time dimensions by showing that the n-fold tensor product of one-particle representations of the Poincare group for n [ges] 2 contains a countable infinity of discrete, zero-mass representations. We relate this result to the well-known "bound" states in every charge sector of the fermion Fock space.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/21624/1/0000003.pd
Endothelial Progenitor Cells Conditioned Medium Supports Number of GABAergic Neurons and Exerts Neuroprotection in Cultured Striatal Neuronal Progenitor Cells.
There is growing evidence that stem and progenitor cells exert regenerative actions by means of paracrine factors. In line with these notions, we recently demonstrated that endothelial progenitor cell (EPC)-derived conditioned medium (EPC-CM) substantially increased viability of brain microvascular cells. In the present study, we aimed at investigating whether EPC-CM supports cell survival of cultured striatal progenitor cells. For that purpose, primary cultures from fetal rat embryonic (E14) ganglionic eminence were prepared and grown for 7 days (DIV). EPC-CM was administered from DIV5-7. Treatment of the striatal cultures with EPC-CM resulted in significantly increased densities of GABA-immunoreactive (-ir) neurons. Inhibition of mitogen-activated protein kinase and phosphatidylinositol-3-kinase, but not of the ROCK pathway, significantly attenuated the EPC-CM induced increase in GABA-ir cell densities. Similar results were observed when EPC-CM was subjected to proteolytic digestion and lipid extraction. Furthermore, inhibition of translation abolished the EPC-CM induced effects. Importantly, EPC-CM displayed neuroprotection against 3-nitropropionic acid induced toxicity. These findings demonstrate that EPC-derived paracrine factors substantially promote survival and/or differentiation of cultured striatal progenitor cells involving both proteinaceous factors and lipidic factors. In sum, EPC-CM constituents might lead to a novel cell-free therapeutic strategy to challenge neuronal degeneration
Selective inferior petrosal sinus sampling without venous outflow diversion in the detection of a pituitary adenoma in Cushing's syndrome
Introduction: Conventional MRI may still be an inaccurate method for the non-invasive detection of a microadenoma in adrenocorticotropin (ACTH)-dependent Cushing's syndrome (CS). Bilateral inferior petrosal sinus sampling (BIPSS) with ovine corticotropin-releasing hormone (oCRH) stimulation is an invasive, but accurate, intervention in the diagnostic armamentarium surrounding CS. Until now, there is a continuous controversial debate regarding lateralization data in detecting a microadenoma. Using BIPSS, we evaluated whether a highly selective placement of microcatheters without diversion of venous outflow might improve detection of pituitary microadenoma. Methods: We performed BIPSS in 23 patients that met clinical and biochemical criteria of CS and with equivocal MRI findings. For BIPSS, the femoral veins were catheterized bilaterally with a 6-F catheter and the inferior petrosal sinus bilaterally with a 2.7-F microcatheter. A third catheter was placed in the right femoral vein. Blood samples were collected from each catheter to determine ACTH blood concentration before and after oCRH stimulation. Results: In 21 patients, a central-to-peripheral ACTH gradient was found and the affected side determined. In 18 of 20 patients where transsphenoidal partial hypophysectomy was performed based on BIPSS findings, microadenoma was histologically confirmed. BIPSS had a sensitivity of 94% and a specificity of 67% after oCRH stimulation in detecting a microadenoma. Correct localization of the adenoma was achieved in all Cushing's disease patients. Conclusion: BIPSS remains the gold standard in the detection of a microadenoma in CS. Our findings show that the selective placement of microcatheters without venous outflow diversion might further enhance better recognition to localize the pituitary tumo
Consequences of chronic kidney disease in chronic obstructive pulmonary disease
Background: The combination of chronic obstructive pulmonary disease (COPD) and chronic kidney disease (CKD)
is associated with a higher prevalence of comorbidities and increased mortality. The impact of kidney function on
patient-centered outcomes in COPD has not been evaluated.
Methods: Patients from the German COPD and Systemic Consequences - Comorbidities Network (COSYCONET)
cohort COPD were analysed. CKD was diagnosed if the estimated glomerular filtration rate (eGFR) measurements
were < 60 mL/min/1.73m2 at study inclusion and six month later. The effect of CKD, on comorbidities, symptoms
[modified British Medical Research Council dyspnoea scale], physical capacity [six-minute walk test, and timed up
and go] and St George’s Respiratory Questionnaire were analysed. Restricted cubic spline models were used to
evaluate a nonlinear relationship between eGFR with patient-centered outcomes, cox survival analysis was applied
to evaluate mortality.
Results: 2274 patients were analysed, with CKD diagnosed in 161 (7.1%). Spline models adjusted for age, gender,
BMI, FEV1 and cardiovascular comorbidities revealed independent associations between eGFR with modified British
Medical Research Council dyspnoea scale, St George’s Respiratory Questionnaire, (p < 0.001 and p = 0.011), six-minute
walk test (p = 0.015) and timed up and go (p < 0.001). CKD was associated with increased mortality, independently
from for other cardiovascular comorbidities (hazard ratio 2.3; p < 0.001).
Conclusion: These data show that CKD is a relevant comorbidity in COPD patients which impacts on patient-centered
outcomes and mortality
Assessing airway inflammation in clinical practice – experience with spontaneous sputum analysis
<p>Abstract</p> <p>Background</p> <p>The assessment of airway inflammation for the diagnosis of asthma or COPD is still uncommon in pneumology-specialized general practices. In this respect, the measurement of exhaled nitric oxide (NO), as a fast and simple methodology, is increasingly used. The indirect assessment of airway inflammation, however, does have its limits and therefore there will always be a need for methods enabling a direct evaluation of airway inflammatory cell composition. Sampling of spontaneous sputum is a well-known, simple, economic and non-invasive method to derive a qualitative cytology of airway cells and here we aimed to assess today's value of spontaneous sputum cytology in clinical practice.</p> <p>Methods</p> <p>Three pneumologists provided final diagnoses in 481 patients having sputum cytology and we retrospectively determined posterior versus prior probabilities of inflammatory airway disorders. Moreover, in a prospective part comprising 108 patients, pneumologists rated their confidence in a given diagnosis before and after knowing sputum cytology and rated its impact on the diagnostic process on an analogue scale.</p> <p>Results</p> <p>Among the 481 patients, 45% were diagnosed as having asthma and/or airway hyperresponsiveness. If patients showed sputum eosinophilia, the prevalence of this diagnosis was elevated to 73% (n = 109, p < 0.001). The diagnosis of COPD increased from 40 to 66% in patients with neutrophilia (n = 29, p < 0.01).</p> <p>Thirty-three of the 108 patients were excluded from the prospective part (26 insufficient samples, 7 incomplete questionnaires). In 48/75 cases the confidence into a diagnosis was raised after knowing sputum cytology, and in 15/75 cases the diagnosis was changed as cytology provided new clues.</p> <p>Conclusion</p> <p>Our data suggest that spontaneous sputum cytology is capable of assisting in the diagnosis of inflammatory airway diseases in the outpatient setting. Despite the limitations by the semiquantitative assessment and lower sputum quality, the supportive power and the low economic effort needed can justify the use of this method, particularly if the diagnosis in question is thought to have an allergic background.</p
The dialect dictionary
In this chapter, the making of dialect dictionaries is discussed. We dwell on the user-oriented metalexicographical considerations, and on the ensuing macrostructural and microstructural options. Special attention is devoted to fieldwork procedures for unwritten language varieties. We try and answer the basic questions of field work: What?, Where?, Who?, How? And How much
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