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81.
The prevalence of renal stones in renal cystic and malformative conditions exceeds the prevalence of renal stones in the general
population, suggesting that the above-mentioned cystic and malformative disorders favor stone formation. Urinary stasis is
generally assumed to play a major part in the pathogenesis of the nephrolithiasis associated with distorted renal anatomy
due to a delayed washout of crystals and risk of urinary infections. However metabolic factors are also important in the pathogenesis
of stones in these conditions. Indeed, metabolic abnormalities have been observed in the majority of stone-forming patients
with conditions such as horseshoe kidney and ureteropelvic junction obstruction. Five different models of stone formation
can be identified, depending on stone composition, risk of infection stones, and pathogenesis of renal cystic and malformative
conditions. A proper metabolic evaluation should be conducted to diagnose specific, treatable metabolic disorders, thereby
reducing the frequency of recurrent stone disease in these conditions as well. 相似文献
82.
83.
A case is reported of an elevation in values in the measurement of delta optical density at 450 nm in a patient with SS disease, mild hyperbilirubinemia, and anti-E antibody, with the birth of a nonsensitized infant. The role of maternal bilirubin in causing this spurious elevation is discussed. 相似文献
84.
Characterisation of imidazoline I2 binding sites in pig brain 总被引:1,自引:0,他引:1
Anderson NJ Lupo PA Nutt DJ Hudson AL Robinson ES 《European journal of pharmacology》2005,519(1-2):68-74
The imidazoline I2 binding sites in the central nervous system have previously been described in several different species including rat, mouse, rabbit and frog. The present study has investigated the imidazoline I2 binding site, and its relationship to the monoamine oxidase isoforms, in pig whole brain and compared the results obtained with data from other species. Results from saturation binding studies revealed that the imidazoline I2-selective ligand, [3H]2BFI (2-(2-benzofuranyl)-2-imidazoline) labelled a single saturable population of sites with a KD=6.6 nM and Bmax=771.7 fmol/mg protein. The pharmacological characterisation of the sites was similar to that previously reported with a rank order of potency for the imidazoline I2 ligands of 2BFI>BU224>Idazoxan>BU226. Displacement by the imidazoline I1 ligands was low affinity and the monoamine oxidase inhibitors displaced with micromolar affinity. The majority of compounds displaced the binding in a monophasic manner, however, displacement by the putative endogenous ligand, harmane was biphasic. The relative populations of the two monoamine oxidase isoforms revealed a 10 fold greater expression of monoamine oxidase B relative to monoamine oxidase A. These data confirm the presence of imidazoline I2 binding sites in pig brain and show that their pharmacology is characteristic of that seen in other species. The proportion of monoamine oxidase A and B expressed in the pig brain is similar to that seen in the human brain therefore, given the association between imidazoline I2 binding sites and monoamine oxidase, the pig may provide a more useful model for human imidazoline I2 binding sites than other species such as the rat. 相似文献
85.
Pier Luigi Grenga Serena Fragiotta Alessandro Meduri Stefano Lupo Marco Marenco Enzo M. Vingolo 《Canadian journal of ophthalmology. Journal canadien d'ophtalmologie》2013
Objective
To evaluate which of 2 measuring units (bivariate contour ellipse area [BCEA] vs Fujii) yields more accurate measurements of fixation stability, obtained using the MP-1 device, in patients with neovascular age-related macular degeneration (nAMD) treated with intravitreal injections of ranibizumab, during a 12-month follow-up period.Design
Small retrospective, noncomparative, interventional case series.Participants
A total of 25 eyes in 25 patients (13 males, 12 females; mean age 71.72 ± 7.98 years).Methods
All participants were older than 50 years, diagnosed with active subfoveal choroidal neovascularization, had best corrected visual acuity (BCVA) values above 20/100, and all lesion types were included. All patients underwent a loading phase with 3 consecutive intravitreal injections of 0.05 mg ranibizumab at monthly intervals. Patients were retreated after the third injection if they exhibited a 100-μm increase in macular thickness or evidence of intraretinal and/or subretinal fluid and new subretinal hemorrhage, observed with spectral-domain optical coherence tomography and fluorescein angiography. The data collected included BCVA and mean macular sensitivities, BCEA, and fixation patterns, performed at baseline and at months 4 and 12, using the MP-1 device.Results
The mean total injection number was 5.92 ± 1.18 (minimum 3, maximum 8). Mean BCVA at baseline was 0.55 ± 0.28 logMAR and increased significantly to 0.50 ± 0.33 logMAR. Mean macular sensitivity at baseline was 7.06 ± 4.59 dB and increased significantly to 8.40 ± 4.82. Mean BCEA was 2.19 ± 1.38 deg2 and decreased significantly to 1.68 ± 1.43 deg2. Fixation stability patterns, according to the protocol set out by Fujii, did not change significantly during follow-up.Conclusions
Compared with Fujii fixation stability patterns, BCEA correlated better with variations in macular sensitivity and BCVA. BCEA can be added to the traditional parameters used to evaluate the efficacy of intravitreal injections in patients with nAMD. 相似文献86.
The purpose of this article is to describe the efforts in the state of Georgia to train public health nurse-childcare health consultants (PHN-CCHCs) using the framework of the "Core competencies for public health practice." Objectives: The goal of the training was twofold: (1) to prepare a statewide cadre of PHNs as the primary workforce for Georgia's emerging childcare health consultation (CCHC) system and (2) to prepare their district nurse directors to lead and support CCHCs. Design: Administrators attended a 2-day workshop followed by access to executive coaching for their management teams. PHNs participated in a three-phase training program, with phases 1 and 3 offered as 3-day workshops with field experiences, and phase 2 offered online and as a practicum. Sample: Forty-four administrators and over 85 PHN-CCHCs completed the training. Results: Graduates of the program reported satisfaction with training and reported the use of PHN core competencies in CCHC. Graduates also found enhanced skills in using core competencies to be applicable to a variety of population-based practices. Beyond CCHC being instituted in selected health districts, interest in CCHC has occurred statewide. Conclusions: The PHN-CCHC program enhanced the knowledge and use of core competencies and heightened interest in CCHC statewide. 相似文献
87.
Agnese Lupo Krisztina M. Papp-Wallace Parham Sendi Robert A. Bonomo Andrea Endimiani 《Diagnostic microbiology and infectious disease》2013
In the past 2 decades, we have observed a rapid increase of infections due to multidrug-resistant Enterobacteriaceae. Regrettably, these isolates possess genes encoding for extended-spectrum β-lactamases (e.g., blaCTX-M, blaTEM, blaSHV) or plasmid-mediated AmpCs (e.g., blaCMY) that confer resistance to last-generation cephalosporins. Furthermore, other resistance traits against quinolones (e.g., mutations in gyrA and parC, qnr elements) and aminoglycosides (e.g., aminoglycosides modifying enzymes and 16S rRNA methylases) are also frequently co-associated. Even more concerning is the rapid increase of Enterobacteriaceae carrying genes conferring resistance to carbapenems (e.g., blaKPC, blaNDM). Therefore, the spread of these pathogens puts in peril our antibiotic options. Unfortunately, standard microbiological procedures require several days to isolate the responsible pathogen and to provide correct antimicrobial susceptibility test results. This delay impacts the rapid implementation of adequate antimicrobial treatment and infection control countermeasures. Thus, there is emerging interest in the early and more sensitive detection of resistance mechanisms. Modern non-phenotypic tests are promising in this respect, and hence, can influence both clinical outcome and healthcare costs. In this review, we present a summary of the most advanced methods (e.g., next-generation DNA sequencing, multiplex PCRs, real-time PCRs, microarrays, MALDI-TOF MS, and PCR/ESI MS) presently available for the rapid detection of antibiotic resistance genes in Enterobacteriaceae. Taking into account speed, manageability, accuracy, versatility, and costs, the possible settings of application (research, clinic, and epidemiology) of these methods and their superiority against standard phenotypic methods are discussed. 相似文献
88.
Pietrella D Lupo P Rachini A Sandini S Ciervo A Perito S Bistoni F Vecchiarelli A 《Infection and immunity》2008,76(9):4359-4367
Mannoproteins are cell wall components of pathogenic fungi and play major virulence and immunogenic roles with both their mannan and protein moieties. The 65-kDa mannoprotein (MP65) of Candida albicans is a beta-glucanase adhesin recognized as a major target of the human immune response against this fungus, and its recombinant product (rMP65; devoid of the mannan moiety) is presently under consideration as a vaccine candidate. Here we investigated cellular and molecular aspects of the interaction of rMP65 with human antigen-presenting cells. We also assessed the ability of rMP65 to initiate a T-cell response. Both the native mannosylated MP65 (nMP65) and the recombinant product were efficiently bound and taken up by macrophages and dendritic cells. However, contrarily to nMP65, rMP65 did not induce tumor necrosis factor alpha and interleukin-6 release from these cells. On the other hand, rMP65 was rapidly endocytosed by both macrophages and dendritic cells, in a process involving both clathrin-dependent and clathrin-independent mechanisms. Moreover, the RGD sequence inhibited rMP65 uptake to some extent. After internalization, rMP65 partially colocalized with lysosomal membrane-associated glycoproteins 1 and 2. This possibly resulted in efficient protein degradation and presentation to CD4(+) T cells, which proliferated and produced gamma interferon. Collectively, these results demonstrate that the absence of the mannan moiety does not deprive MP65 of the capacity to initiate the pattern of cellular and molecular events leading to antigen presentation and T-cell activation, which are essential features for further consideration of MP65 as a potential vaccine candidate. 相似文献
89.
Mazzocca A Dituri F Lupo L Quaranta M Antonaci S Giannelli G 《Hepatology (Baltimore, Md.)》2011,54(3):920-930
Hepatocellular carcinoma (HCC) occurs in fibrotic liver as a consequence of underlying cirrhosis. The goal of this study was to investigate how the interaction between HCC cells and stromal fibroblasts affects tumor progression. We isolated and characterized carcinoma-associated fibroblasts (CAFs) and paired peritumoral tissue fibroblasts (PTFs) from 10 different patients with HCC and performed coculture experiments. We demonstrated a paracrine mechanism whereby HCC cells secrete lysophostatidic acid (LPA), which promotes transdifferentiation of PTFs to a CAF-like myofibroblastic phenotype. This effect is mediated by up-regulation of specific genes related to a myo/contractile phenotype. After transdifferentiation, PTFs expressed α-smooth muscle actin (α-SMA) and enhanced proliferation, migration, and invasion of HCC cells occur. A pan-LPA inhibitor (α-bromomethylene phosphonate [BrP]-LPA), or autotaxin gene silencing, inhibited this PTF transdifferentiation and the consequent enhanced proliferation, migration, and invasion of HCC cells. In vivo, PTFs coinjected with HCC cells underwent transdifferentiation and promoted tumor progression. Treatment with BrP-LPA blocked transdifferentiation of PTFs, down-regulated myofibroblast-related genes, and slowed HCC growth and progression. Patients with larger and metastatic HCC and shorter survival displayed higher serum levels of LPA. Analysis of microdissected tissues indicated that stroma is the main target of the LPA paracrine loop in HCC. As a consequence, α-SMA-positive cells were more widespread in tumoral compared with paired peritumoral stroma. Conclusion: Our data indicate that LPA accelerates HCC progression by recruiting PTFs and promoting their transdifferentiation into myofibroblasts. Inhibition of LPA could prove effective in blocking transdifferentiation of myofibroblasts and tumor progression. 相似文献