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101.
The Moraxella catarrhalis immunoglobulin D (IgD)-binding protein (MID) is a 200-kDa outer membrane protein displaying a unique and specific affinity for human IgD. MID is found in the majority of M. catarrhalis strains. In the present paper, we show that MID-expressing M. catarrhalis strains agglutinate human erythrocytes and bind to type II alveolar epithelial cells. In contrast, M. catarrhalis isolates with low MID expression levels and two mutants deficient in MID, but with readily detectable UspA1 expression, do not agglutinate erythrocytes and have a 50% lower adhesive capacity. To examine the adhesive part of MID, the protein was dissected into nine fragments covering the entire molecule. The truncated MID proteins were expressed in Escherichia coli, purified, and used for raising polyclonal antibodies in rabbits. Interestingly, by using recombinant fragments, we show that the hemagglutinating and adhesive part of MID is localized within the 150-amino-acid fragment MID(764-913). In addition, antibodies against full-length MID, MID(764-913), or a 30-amino-acid consensus sequence (MID(775-804)) inhibited adhesion to alveolar epithelial cells. Antibodies against UspA1, an outer membrane protein expressed in essentially all M. catarrhalis strains, also inhibited adhesion, suggesting that both MID and UspA1 are needed for optimal attachment to epithelial cells. Taken together, in addition to MID-dependent IgD binding, we have demonstrated that the outer membrane protein MID is a novel adhesin that would be a suitable target for a future vaccine against M. catarrhalis. 相似文献
102.
Ruperto N Meiorin S Iusan SM Ravelli A Pistorio A Martini A 《Current rheumatology reports》2008,10(2):142-146
The Delphi Technique and Nominal Group Technique are two well-recognized consensus-formation methodologies specifically designed
to combine judgments from a group of experts. The Delphi Technique utilizes a series of well-defined questionnaire-based surveys,
whereas Nominal Group Technique is a structured face-to-face meeting designed to facilitate consensus. Consensus-formation
techniques require that each step build on the results of the previous steps. In this review, we describe these techniques,
how they work, and their practical application in pediatric rheumatology, where they have been widely used to develop the
outcome measures of several chronic rheumatic diseases, including juvenile idiopathic arthritis, rheumatoid arthritis, systemic
lupus erythematosus, and idiopathic inflammatory myopathies, as well as the classification criteria for juvenile systemic
sclerosis and juvenile vasculitides. 相似文献
103.
Sabrina Lueck Juergen Sindermann Sven Martens Mirela Scherer 《Journal of artificial organs》2016,19(3):305-309
Peripartum cardiomyopathy (PPCM) challenges different disciplines including gynecologists, cardiologists and cardiac surgeons. It is a severe cardiac failure occurring at the end of pregnancy or within the first months after delivery. Urgent intervention is necessary to stabilize hemodynamics with appropriate medication and mechanical assist support. Data of 4 patients with PPCM at a mean age of 28.2 years were analyzed retrospectively. Echocardiography was used to evaluate cardiac function. Despite varying courses of PPCM all women received left ventricular assist devices (LVAD) since their hemodynamics could not be stabilized by medical treatment. Mean gestational week at delivery was 31.5 ± 4.9. Left ventricular ejection fractions of all patients were severely impaired (17.8 ± 3.5 %) before LVAD implantations. After long-term mechanical support (282 and 417 days, respectively) 2 patients were successfully transplanted. Two other females could be weaned from LVAD therapy after 944 and 612 days, respectively. LVAD explanations were performed according to a standardized weaning protocol. Myocardial recovery was confirmed by regular echocardiography, spiroergometry and right heart catheterization. Mechanical assist device support is a surgical strategy either as bridge to transplantation or as bridge to recovery for patients with PPCM. 相似文献
104.
Abysmal prognosis of patients with type 2 diabetes entering dialysis. 总被引:10,自引:10,他引:0
F Chantrel I Enache M Bouiller I Kolb K Kunz P Petitjean B Moulin T Hannedouche 《Nephrology, dialysis, transplantation》1999,14(1):129-136
INTRODUCTION: The importance of non-insulin-dependent diabetes mellitus (type II diabetes) as a leading cause of end-stage renal disease is now widely recognized. The purpose of this study was to assess life-prognosis and its predictors in a cohort of patients newly entering dialysis. MATERIAL AND METHODS: Eighty-four consecutive type II diabetes patients (40% of all patients) starting dialysis between 01/01/95 and 31/12/96 were studied retrospectively, focusing on clinical data at inception and life-prognosis after a mean follow-up of 211 days. Patients were divided into three groups, according to onset of renal failure: acute 11% (9/84), chronic 61% (51/84) and acutely aggravated chronic renal failure 28% (25/84). RESULTS: Patients (mean age 67 years) had long-standing diabetes (mean duration approximately 15 years), heavy proteinuria (approximately 3 g/24h) and diabetic retinopathy (67%). The average creatinine clearance (Cockcroft's formula) was 13 ml/min. Cardiovascular diseases were highly prevalent at the start of dialysis: history of myocardial infarction (26%), angina (36%) and acute left ventricular dysfunction (67%). More than 80% of the patients underwent the first session dialysis under emergency conditions, a situation in part related to late referral to the nephrology division (63% for chronic patients). A great majority of the patients were overhydrated when starting dialysis, as evidenced by the average weight loss of 6 kg, during the first month of dialysis, required to reach dry weight. Nearly 64% of the patients presented high blood pressure (> 140/90 mmHg) when starting dialysis despite antihypertensive therapy (mean: 2.3 drugs). The outcome of this type II diabetes population was dramatic: 32% (27/84) died after a mean follow-up of 211 days, mostly from cardiovascular diseases. The rate of recovery of renal function was low in both the acute and the acutely aggravated renal failure group (30% and 24%, respectively). Of note, iatrogenic nephrotoxic agents accounted for renal function impairment in nearly 30% of patients. CONCLUSION: Our observational study illustrates the high burden of cardiovascular diseases contrasting with sub-optimal cardiovascular therapeutic interventions in type II diabetes patients entering dialysis. Factors aggravating renal failure were mainly iatrogenic, and therefore largely avoidable. Late referral generally implied a poor clinical condition at the start of dialysis. 相似文献
105.
Greta Maria Dancu Alina Popescu Roxana Sirli Mirela Danila Felix Bende Cristi Tarta Ioan Sporea 《Medicine》2021,100(51)
Acute pancreatitis is a common disease, and the mortality rate can be high. Thus, a risk assessment should be performed early to optimize treatment. We compared simple prognostic markers with the bedside index for severity in acute pancreatitis (BISAP) scoring system to identify the best predictors of severity and mortality.This retrospective study stratified disease severity based on the revised Atlanta criteria. The accuracies of the markers for predicting severe AP (SAP) were assessed using receiver operating characteristic curves. The sensitivity, specificity, positive predictive value, and negative predictive value were calculated for each marker. Multivariate logistic regression analyses were used to identify independent predictors of SAP and mortality.The area under the curve (AUC) for the BISAP score was classified as fair for predicting SAP. The neutrophil-to-lymphocyte ratio at 48 hours (NLR48 h) and the C-reactive protein level at 48 hours (CRP48 h) had the best AUCs and were independently associated with SAP. When both criteria were met, the AUC was 0.89, sensitivity was 68%, and specificity was 92%. CRP48 h and hematocrit at 48 hours were independently associated with mortality.NLR48 h and CRP48 h were independently associated with SAP but not superior to the BISAP score at admission. Assessing NLR48 h and CRP48H together was most suitable for predicting SAP. The CRP level was a good predictive marker for mortality. 相似文献
106.
Kerstin Narr Yusuf I. Ertuna Benedict Fallet Karen Cornille Mirela Dimitrova Anna-Friederike Marx Katrin Martin Tiago Abreu Mota Marco Künzli David Schreiner Tobias M. Brunner Mario Kreutzfeldt Ingrid Wagner Florian Geier Lukas Bestmann Max Lhning Doron Merkler Carolyn G. King Daniel D. Pinschewer 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(46)
107.
Naman K. Gupta Christopher McMahon Ronny Sutarto Tianyu Shi Rantong Gong Haofei I. Wei Kyle M. Shen Feizhou He Qianli Ma Mirela Dragomir Bruce D. Gaulin David G. Hawthorn 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(34)
During the last decade, translational and rotational symmetry-breaking phases—density wave order and electronic nematicity—have been established as generic and distinct features of many correlated electron systems, including pnictide and cuprate superconductors. However, in cuprates, the relationship between these electronic symmetry-breaking phases and the enigmatic pseudogap phase remains unclear. Here, we employ resonant X-ray scattering in a cuprate high-temperature superconductor (Nd-LSCO) to navigate the cuprate phase diagram, probing the relationship between electronic nematicity of the Cu 3d orbitals, charge order, and the pseudogap phase as a function of doping. We find evidence for a considerable decrease in electronic nematicity beyond the pseudogap phase, either by raising the temperature through the pseudogap onset temperature T* or increasing doping through the pseudogap critical point, p*. These results establish a clear link between electronic nematicity, the pseudogap, and its associated quantum criticality in overdoped cuprates. Our findings anticipate that electronic nematicity may play a larger role in understanding the cuprate phase diagram than previously recognized, possibly having a crucial role in the phenomenology of the pseudogap phase.There is a growing realization that the essential physics of the cuprate high-temperature superconductors, and perhaps other strongly correlated materials, involves a rich interplay between different electronic symmetry-breaking phases (1–3) like superconductivity, spin or charge density wave (SDW or CDW) order (4–7), antiferromagnetism, electronic nematicity (8–14), and possibly other orders such as pair density wave order (15) or orbital current order (16).One or more of these orders may also be linked with the existence of a zero-temperature quantum critical point (QCP) in the superconducting state of the cuprates, similar to heavy-fermion, organic, pnictide, and iron-based superconductors (17–19). The significance of the QCP in describing the properties of the cuprates, as a generic organizing principle where quantum fluctuations in the vicinity of the QCP impact a wide swath of the cuprate phase diagram, remains an open question. Evidence for such a QCP and its influence include a linear in temperature resistivity extending to low temperature, strong mass enhancement via quantum oscillation studies (20), and an enhancement in the specific heat (21) in the field induced normal state, with some of the more-direct evidence for a QCP in the cuprates coming from measurements in the material (Nd-LSCO). Moreover, the QCP also appears to be the endpoint of the pseudogap phase (21) that is marked, among other features, by transition of the electronic structure from small Fermi surface that is folded or truncated by the antiferromagnetic zone boundary in the pseudogap phase to a large Fermi surface at higher doping (22, 23) that is consistent with band structure calculations (24). However, in the cuprates, neither the QCP nor the change in the electronic structure have been definitively associated with a particular symmetry-breaking phase.In this article, we interrogate the possibility that the cuprates exhibit a connection between electronic nematic order, the pseudogap, and its associated QCP. In the pnictide superconductors, which are similar in many respects to the cuprates, electronic nematic order is more clearly established experimentally, and there have been reports of nematic fluctuations (25), non-Fermi liquid transport (26), and a change in the topology of the Fermi surface associated with a nematic QCP (27). Electronic nematicity refers to a breaking of rotational symmetry of the electronic structure in a manner that is not a straightforward result of crystalline symmetry, such that an additional electronic nematic order parameter beyond the structure would be required to describe the resulting phase. The manifestation of nematic order may therefore depend on the details of the crystal structure of the materials, such as whether the structure is tetragonal or orthorhombic. However, such a state can be difficult to identify in materials that have orthorhombic structures, which would naturally couple to any electronic nematic order and vice versa. Despite these challenges, experimental evidence for electronic nematic order that is distinct from the crystal structure include reports of electronic nematicity from bulk transport (8–10) and magnetometry measurements (11) in (YBCO), scanning tunneling microscopy (STM) (13, 14, 28) in (Bi2212), inelastic neutron scattering (12) in YBCO, and resonant X-ray scattering (29) in (La,Nd,Ba,Sr,Eu)2CuO4. Moreover, STM studies in Bi2212 have reported intraunit cell nematicity disappearing around the pseudogap endpoint (30), which also seems to be a region of enhanced electronic nematic fluctuations (31, 32). In YBCO, there have also been reports of association between nematicity and the pseudogap onset temperature (9, 11).Here, we use resonant X-ray scattering to measure electronic nematic order in the cuprate Nd-LSCO as a function of doping and temperature to explore the relationship of electronic nematicity with the pseudogap phase. While evidence that a quantum critical point governs a wide swath of the phase diagram in hole-doped cuprates and is generic to many material systems remains unclear, investigation of Nd-LSCO provides the opportunity to probe the evolution of electronic nematicity over a wide range of doping in the same material system where some of the most compelling signatures of quantum criticality and electronic structure evolution have been observed. These include a divergence in the heat capacity (21), a change in the electronic structure from angle-dependent magnetoresistance (ADMR) measurements (24) in the vicinity of the QCP at x = 0.23, and the onset of the pseudogap (23). Our main result is that we observe a vanishing of the electronic nematic order in Nd-LSCO as hole doping is either increased above x = 0.23, which has been identified as the QCP doping for this system (21), or when temperature is increased above the pseudogap onset temperature T* (23). These observations indicate that electronic nematicity in Nd-LSCO is intimately linked to the pseudogap phase. 相似文献
108.
(1)H NMR spectroscopy of urine has been applied to exploring metabolomic differences between people diagnosed with Balkan endemic nephropathy (BEN), and treated by haemodialysis, and those without overt renal disease in Romania and Bulgaria. Convenience sampling was made from patients receiving haemodialysis in hospital and healthy controls in their village. Principal component analysis clustered healthy controls from both countries together. Bulgarian BEN patients clustered separately from controls, though in the same space. However, Romanian BEN patients not only also clustered away from controls but also clustered separately from the BEN patients in Bulgaria. Notably, the urinary metabolomic data of two people sampled as Romanian controls clustered within the Romanian BEN group. One of these had been suspected of incipient symptoms of BEN at the time of selection as a 'healthy' control. This implies, at first sight, that metabolomic analysis can be predictive of impending morbidity before conventional criteria can diagnose BEN. Separate clustering of BEN patients from Romania and Bulgaria could indicate difference in aetiology of this particular silent renal atrophy in different geographic foci across the Balkans. 相似文献
109.
Objectives The aim of this study was to investigate the interaction of the anticancer drug mitoxantrone with non‐ionic micelles, as simple model systems of biological membranes. Methods UV‐VIS absorption spectroscopy was used to quantify the drug–surfactant micelle interactions in terms of the binding constant and the micelle–water partition coefficient of the drug. Key findings Interaction of mitoxantrone with non‐ionic micelles reduces the dimerization process of mitoxantrone, the drug molecules being encapsulated into micelles as monomer. The strength of the interaction between mitoxantrone and non‐ionic micelles is higher at pH 10 than at pH 7.4, and depends on the surfactant in the order Tween 80 > Tween 20 > Triton X‐100. The higher partition coefficient at pH 10 compared to pH 7.4 suggests that at basic pH the deprotonated mitoxantrone is incorporated more efficiently into the hydrophobic medium of non‐ionic micelles compared to physiological pH, when the protonated drug is predominant. Conclusions These results on simple model systems miming the drug–membrane interactions contribute to the elucidation of the behaviour of the drug in vivo, as well as the possible utilization of surfactant micelles as drug carriers. 相似文献
110.
Kašnar-Šamprec J Ratkaj I Mišković K Pavlak M Baus-Lončar M Kraljević Pavelić S Glavaš-Obrovac L Žinić B 《Investigational new drugs》2012,30(3):981-990
New N-1-sulfonylpyrimidines showed potent growth inhibitory activity against human and mouse tumour cells of different origin. 1-(p-toluenesulfonyl)cytosine (TsC) and 1-(p-toluenesulfonyl)cytosine hydrochloride (TsC × HCl) inhibited the growth of human cervical carcinoma cells (HeLa), and had no significant cytotoxic effects on normal human foreskin fibroblasts (BJ). TsC and TsC × HCl interfered with the HeLa cell cycle progression bringing about the accumulation of G1 phase cells and the induction of apoptosis. Antiproliferative effects of TsC and TsC × HCl were additionally confirmed by investigating de novo synthesis of RNA, DNA and proteins in HeLa cells. Monitoring gene expression using DNA Chip Analysis and quantitative PCR showed that TsC × HCl affects the expression of several cell-cycle regulating genes implying that cell cycle arrest and DNA damage-induced apoptosis might account for the observed cellular effects. In vivo experiments revealed low toxicity of TsC × HCl, as demonstrated by unaltered haematological and metabolic blood parameters. In conclusion, potent antitumour efficacy and low toxicity of new compounds in comparison with the common chemotherapy drug 5-FU make them promising anticancer agents. Additional pre-clinical and clinical studies are warranted to illuminate the mode of action of these newly synthesized compounds in vivo, which would lay the groundwork for their further optimization. 相似文献