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101.
102.
The asialoglycoprotein (ASGP) receptor is a wellcharacterized hepatic receptor that is recycled via the common cellular process of receptor-mediated endocytosis (RME). The RME process plays an integral part in the proper trafficking and routing of receptors and ligands in the healthy cell. Thus, the missorting or altered transport of proteins during RME is thought to play a role in several diseases associated with hepatocyte and liver dysfunction. Previously,we examined in detail alterations that occur in hepatocellular RME and associated receptor functions as a result of one particular liver injury, alcoholic liver disease (ALD). The studies revealed profound ethanolmediated impairments to the ASGP receptor and the RME process, indicating the importance of this receptor and the maintenance of proper endocytic events in normal tissue. To further clarify these observations,studies were performed utilizing knockout mice (lacking a functional ASGP receptor) to which were administered several liver toxicants. In addition to alcohol, we examined the effects following administration of anti-Fas (CD95) antibody, carbon tetrachloride (CCl4) and lipopolysaccharide (LPS)/galactosamine. The results of these studies demonstrated that the knockout mice sustained enhanced liver injury in response to all of the treatments, as shown by increased indices of liver damage, such as enhancement of serum enzyme levels,histopathological scores, as well as hepatocellular death.Overall, the work completed to date suggests a possible link between hepatic receptors and liver injury. In particular, adequate function and content of the ASGP receptor may provide protection against various toxinmediated liver diseases.  相似文献   
103.
Fibroepithelial lesions (FELs) are a heterogeneous group of tumours comprising fibroadenomas (FAs) and phyllodes tumours (PTs). Here we used a 16-gene panel that was previously discovered to be implicated in pathogenesis and progression, to characterise a large international cohort of FELs via targeted sequencing. The study comprised 303 (38%) FAs and 493 (62%) PTs which were contributed by the International Fibroepithelial Consortium. There were 659 (83%) Asian and 109 (14%) non-Asian FELs, while the ethnicity of the rest was unknown. Genetic aberrations were significantly associated with increasing grade of PTs, and were detected more in PTs than FAs for MED12, TERT promoter, RARA, FLNA, SETD2, TP53, RB1, EGFR, and IGF1R. Most borderline and malignant PTs possessed ≥ 2 mutations, while there were more cases of FAs with ≤ 1 mutation compared to PTs. FELs with MED12 mutations had significantly higher rates of TERT promoter, RARA, SETD2, EGFR, ERBB4, MAP3K1, and IGF1R aberrations. However, FELs with wild-type MED12 were more likely to express TP53 and PIK3CA mutations. There were no significant differences observed between the mutational profiles of recurrent FAs, FAs with a history of subsequent ipsilateral recurrence or contralateral occurrence, and FAs without a history of subsequent events. We identified recurrent mutations which were more frequent in PTs than FAs, with borderline and malignant PTs harbouring cancer driver gene and multiple mutations. This study affirms the role of a set of genes in FELs, including its potential utility in classification based on mutational profiles. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
104.
Escherichia coli strains carrying recombinant plasmids encoding either the type 1 fimbria of Salmonella enterica serovar Typhimurium or the G fimbria of E. coli exhibited binding of human 125I-Glu-plasminogen and enhanced the tissue-type plasminogen activator-catalyzed conversion of plasminogen to plasmin. Purified type 1 or G fimbriae similarly bound plasminogen and enhanced its activation. The binding of plasminogen did not involve the characteristic carbohydrate-binding property of the fimbriae but was inhibited at low concentrations by the lysine analog -aminocaproic acid. Because these fimbrial types bind to laminin of basement membranes (M. Kukkonen et al., Mol. Microbiol. 7:229–237, 1993; S. Saarela et al., Infect. Immun. 64:2857–2860, 1996), the results demonstrate a structural unity in the creation and targeting of bacterium-bound proteolytic plasmin activity to basement membranes.  相似文献   
105.

Objective

To identify risk factors for chronic kidney disease progression in Brazilian children and to evaluate the interactions between factors.

Methods

This was a multicenter prospective cohort in São Paulo, involving 209 children with CKD stages 3–4. The study outcome included: (a) death, (b) start of kidney replacement therapy, (c) eGFR decrease >50% during the followup. Thirteen risk factors were tested using univariate regression models, followed by multivariable Cox regression models. The terms of interaction between the variables showing significant association with the outcome were then introduced to the model.

Results

After a median follow-up of 2.5 years (IQR = 1.4–3.0), the outcome occurred in 44 cases (21%): 22 started dialysis, 12 had >50% eGFR decrease, seven underwent transplantation, and three died. Advanced CKD stage at onset (HR = 2.16, CI = 1.14–4.09), nephrotic proteinuria (HR = 2.89, CI = 1.49–5.62), age (HR = 1.10, CI = 1.01–1.17), systolic blood pressure Z score (HR = 1.36, CI = 1.08–1.70), and anemia (HR = 2.60, CI = 1.41–4.77) were associated with the outcome. An interaction between anemia and nephrotic proteinuria at V1 (HR = 0.25, CI = 0.06–1.00) was detected.

Conclusions

As the first CKD cohort in the southern hemisphere, this study supports the main factors reported in developed countries with regards to CKD progression, affirming the potential role of treatments to slow CKD evolution. The detected interaction suggests that anemia may be more deleterious for CKD progression in patients without proteinuria and should be further studied.  相似文献   
106.

Aim

This article explores and describes participatory action research (PAR) as a preferred method in addressing nursing practice issues. This is the first study that used PAR with public health nurses (PHNs) in Canada to develop a professional practice model.

Background

Participatory action research is a sub‐category of action research that incorporates feminist and critical theory with foundations in the field of social psychology. For nurses, critical analysis of long‐established beliefs and practices through PAR contributes to emancipatory knowledge regarding the impact of traditional hierarchies on their practice.

Design

This study used participatory action, a non‐traditional but systematic research method, which assisted participants to develop a solution to a long‐standing organizational issue.

Method

The stages of generating concerns, participatory action, acting on concerns, reflection and evaluation were implemented from 2012 ‐ 2013 in an urban Canadian city, to develop a professional practice model for PHNs.

Findings

Four sub‐themes specific to PAR are discussed. These are “participatory action research engaged PHNs in development of a professional practice model;” “the participatory action research cycles of “Look, Think, Act” expanded participants’ views;” “participatory action research increased awareness of organizational barriers;” and “participatory action research promoted individual empowerment and system transformation.”

Conclusions

This study resulted in individual and system change that may not have been possible without the use of PAR. The focus was engagement of participants and recognition of their lived experience, which facilitated PHNs’ empowerment, leadership and consciousness‐raising.  相似文献   
107.
108.
In an attempt to design a targeted drug delivery system to tumors' over-expressing H-ferritin specifically recognized by a monoclonal antibody, AMB8LK, a cationic emulsion - AMB8LK conjugate was prepared. A novel cross-linker molecule bearing maleimide group was synthesized and added to cationic emulsion formulation for AMB8LK Fab' fragment covalent coupling. NMR spectroscopy confirmed the cross-linker synthesis and the preservation of the active maleimide function. SDS gel-electrophoresis results corroborated the formation of the Fab' fragment. Different densities of Fab' fragments (10-200 Fab'/oil droplet) were conjugated to emulsion droplet interface and no changes in the physico-chemical properties were observed ( approximately 120 nm size and zeta potential of approximately +30 mV). The coupling efficiency ranged from 55% to 70% and was visualized by TEM showing gold particles attached to the droplet interface. Cell culture studies demonstrated specific binding to cells as confirmed by the occurrence of the marked reduction in binding when free AMB8LK Mab was incubated before adding the AMB8LK-emulsion conjugate to the cells. The coupling of AMB8LK Fab' fragment to the cationic emulsion increased the cells uptake by 50% as compared to non-conjugated respective cationic emulsion. Appropriate conditions were, thus, identified for coupling AMB8LK Fab' fragment to cationic emulsion without altering the specificity and affinity of the Mab fragment to the tumor antigen.  相似文献   
109.
110.
Biodegradable cross-linked albumin microcapsules for embolization   总被引:1,自引:0,他引:1  
The interfacial polymerization process used in the present study produced individual cross-linked albumin microcapsules, the particle size of which depended on the emulsification stirring rate. The variation in cross-linking agent concentration altered the microcapsule wall properties. As shown by SEM observations, microcapsules prepared with low acyl chloride concentrations presented rippled surfaces, while the surfaces of the microcapsules prepared with high acyl chloride concentrations were smooth. It was then suggested that the membranes of the weakly cross-linked microcapsules consisted of cross-linked and denatured albumin. Embolization experiments in the dog kidney showed that the weakly cross-linked microcapsules were biodegradable within 7 days, whereas the highly cross-linked microcapsules were degraded over more than 14 days and led to prolonged ischaemia. The results of the histological experiments carried out on a further eight dogs supported the previous findings yielded by the angiographical experiments. Moreover, they indicated that no foreign body reaction occurred. The lack of this inflammatory granuloma should be attributed to the rapid biodegradation of the microcapsules which produced reversible ischaemic lesions.  相似文献   
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