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81.
82.
Objective: Young people with asthma often lack engagement in self-management. Smartphone apps offer an attractive, immediate method for obtaining asthma information and self-management support. In this research we developed an evidence-based asthma app tailored to young peoples needs, created using a participatory design approach to optimize user engagement. This paper describes the participatory design process. Methods: This multi-phased research included concept generation and ideation of app design by young people with asthma, and development of asthma information by the research team. Clinical review was sought regarding safety and accuracy of app content. Participants suggestions for improvement and any problems with the app were logged throughout. Our young co-designers were invited back to test a high fidelity prototype app using a “think aloud” process and completed a usability questionnaire. Results: Twenty asthma patients aged 15-24 years contributed to the initial app design. Three respiratory specialists and two pharmacists suggested minor corrections to clinical terminology in the app which were all incorporated. Nine co-designers acted as expert reviewers of the prototype app, of whom eight completed a usability questionnaire. Median usability scores (maximum score 6) indicated high satisfaction with app content, usefulness and ease of use [median item score 5.3 (range 4.7-6.0)]. All feedback was incorporated to create an updated prototype app. Conclusions: A clinically sound asthma app has been developed which is considered highly acceptable to the young co-designers. A six-week test of the engagement, acceptability, and usefulness of the app in young people not involved in the participatory design will follow. 相似文献
83.
K Karthik SR Sundararajan J Dheenadhayalan S Rajasekaran 《Indian Journal of Orthopaedics》2011,45(1):33-38
Background:
Intra-articular loose bodies following simple dislocations can lead to early degeneration. Nonconcentric reduction may indicate retained loose bodies and offer a method to identify patients requiring exploration so that this undesirable outcome can be avoided.Materials and Methods:
One hundred and seventeen consecutive simple dislocations of the hip presenting to the hospital from January 2000 to June 2006 were assessed for congruency after reduction by fluoroscopic assessment of passive motion in the operating room as well as with good quality radiographs. Computerized tomography (CT) scan with 2-mm cuts was done for confirmation of reduction and to identify the anatomy of loose bodies. Patients with nonconcentric reduction underwent open exploration to identify the etiology of the dislocation and for removal of loose bodies. Thomson and Epstein clinical and radiological criteria were used to assess the outcome.Results:
Twelve of the one hundred and seventeen (10%) dislocations had incongruent reduction, which was identified by the break in Shenton’s line and increase in medial joint space in seven patients, increase in the superior joint space in three patients, or increase in the joint space as a whole in two patients. CT scan identified the origin of the osteocartilaginous fragment as being from the acetabulum in six patients, the femoral head in four, and from both in one. One patient had an inverted posterior labrum. Following debridement, congruent reduction was achieved in all patients. At an average follow-up of 5 years (range: 2 years 5 months to 8 years), the outcome as evaluated by Thompson and Epstein clinical criteria was excellent in eleven cases and good in one case; the radiological outcome was excellent in eight cases and good in four cases.Conclusions:
Intra-articular loose bodies were identified by nonconcentric reduction in 12 out of 117 patients with simple hip dislocation. Careful evaluation by fluoroscopy and good quality radiographs are indicated following reduction of hip dislocations. 相似文献84.
Regulation of stimulated integrin surface expression in human neutrophils by tyrosine phosphorylation 总被引:4,自引:0,他引:4
The control of the adhesive properties of human neutrophils is an essential element of their defense function. One level at which this control is exerted involves the upregulation of the surface expression of beta 2-integrins. In this study, we have examined the potential involvement of tyrosine phosphorylation in the latter process. Two inhibitors of tyrosine kinases with differing modes of action, erbstatin and herbimycin A, were found to inhibit the expression of CD11b and CD18 stimulated by chemotactic factors (fMet-Leu-Phe or leukotriene B4) or growth factors (tumor necrosis factor alpha). This inhibition was not shared by an inactive analog of erbstatin or by the protein kinase C inhibitor Ro 31-8330. Erbstatin also inhibited the unveiling of activation-specific neoepitopes detected by antibody CBRM1/5. Pretreatment of neutrophils (but not of endothelial cells) with erbstatin inhibited the stimulation of neutrophils' adherence to endothelial cells induced by fMet-Leu-Phe. Augmentation of tyrosine phosphorylation by inhibiting tyrosine phosphatases using hydroperoxyvanadate led to an increased surface expression of CD11b and CD18 and enhanced the adhesion of neutrophils to endothelial cells. Finally, the leumedin NPC 15669, which had previously been shown to inhibit stimulated CD11b expression and neutrophil adherence to endothelial cells and to exhibit anti-inflammatory properties in various in vivo models of inflammation, inhibited the stimulation of tyrosine, phosphorylation induced by fMet-Leu-Phe. Taken together, these data establish a strong correlation between tyrosine phosphorylation and integrin upregulation in stimulated human neutrophils. 相似文献
85.
Involvement of guanine nucleotide binding proteins in neutrophil activation and priming by GM-CSF 总被引:4,自引:0,他引:4
Pre-incubation of human neutrophils with pertussis toxin significantly inhibited the neutrophil-directed biologic actions of granulocyte- macrophage colony-stimulating factor (GM-CSF) in three separate assays: the induction of c-fos mRNA, the enhancement of both platelet- activating factor-induced mobilization of intracellular calcium, and stimulation of leukotriene synthesis by the calcium ionophore A23187. Cholera toxin did not have an effect on the latter two assays. Pre- treatment of human neutrophils with pertussis toxin did not affect the binding of GM-CSF to its surface receptor. These results provide the first evidence that a pertussis toxin substrate plays an important mediatory role in the mechanism of action of GM-CSF. 相似文献
86.
PGE1 accelerates thrombolysis by tissue plasminogen activator 总被引:14,自引:0,他引:14
Platelets are an active element in the generation of thrombus and may influence rates of thrombolysis during the administration of plasminogen activators. To assess the potential importance of platelet aggregation in the thrombolytic response to plasminogen activators, we measured rates of thrombolysis induced by tissue plasminogen activator in the presence and absence of a coinfusion of prostaglandin E1 in a rabbit jugular vein model of thrombosis. Rates of lysis were quantified by measuring the half-time for lysis of the thrombus. At all concentrations of tissue plasminogen activator used, prostaglandin E1 markedly reduced the half-time for clot lysis and enhanced somewhat the overall extent of thrombolysis, without affecting significantly either the degree of fibrinogen depletion or the animals' mean arterial pressures. These effects on thrombolytic efficacy were accompanied by ex vivo evidence of platelet inhibition. These data suggest that the antiplatelet prostaglandin E1 may be a very useful adjunctive agent in thrombolytic therapy primarily by virtue of the significant improvement in the rate of thrombolysis that its use affords. 相似文献
87.
Human myeloperoxidase gene expression in acute leukemia 总被引:2,自引:0,他引:2
88.
A Parolia M Kundabala NN Rao† SR Acharya P Agrawal† M Mohan‡ M Thomas 《Australian dental journal》2010,55(1):59-64
Background: Permanent teeth pulp exposures have traditionally been treated with calcium hydroxide pulp capping. The aim of this study was to investigate the response of human pulp tissue which were mechanically exposed to a new material, Propolis and compare it with two existing and commonly used pulp capping agents (mineral trioxide aggregate and Dycal).
Methods: Thirty-six intact human premolars were mechanically exposed. Teeth were divided into six groups of 6 teeth each and were capped with Propolis, mineral trioxide aggregate and Dycal. Final restoration was done with posterior composite resin using light cured glass ionomer cement as a liner. The teeth were then extracted on the 15th or the 45th day and processed for histological evaluation.
Results: Differences in inflammatory response and dentine bridge formation of the exposed pulp to the three different materials were statistically calculated using chi-square test and were found to be non-significant. There was more pulp inflammation in teeth treated with Dycal than with Propolis and MTA on the 15th as well as on the 45th day. Propolis and MTA showed bridge formation in more teeth, and the bridges were in closer proximity to pulp capping material than teeth treated with Dycal on the 45th day.
Conclusions: The response of pulps to Propolis as a pulp capping agent was comparable to MTA and Dycal. 相似文献
Methods: Thirty-six intact human premolars were mechanically exposed. Teeth were divided into six groups of 6 teeth each and were capped with Propolis, mineral trioxide aggregate and Dycal. Final restoration was done with posterior composite resin using light cured glass ionomer cement as a liner. The teeth were then extracted on the 15th or the 45th day and processed for histological evaluation.
Results: Differences in inflammatory response and dentine bridge formation of the exposed pulp to the three different materials were statistically calculated using chi-square test and were found to be non-significant. There was more pulp inflammation in teeth treated with Dycal than with Propolis and MTA on the 15th as well as on the 45th day. Propolis and MTA showed bridge formation in more teeth, and the bridges were in closer proximity to pulp capping material than teeth treated with Dycal on the 45th day.
Conclusions: The response of pulps to Propolis as a pulp capping agent was comparable to MTA and Dycal. 相似文献
89.
Identification of the molecular defect in the erythrocyte membrane skeleton of some kindreds with hereditary spherocytosis 总被引:12,自引:0,他引:12
We have localized the molecular alteration in the membrane skeleton of two of four kindreds with hereditary spherocytosis (HS) to an alteration in the spectrin-protein-4.1 interaction due to a defective spectrin molecule. The defective spectrin-protein-4.1 interaction in these kindreds (referred to as type I HS) leads to a weakened spectrin- protein-4.1-actin ternary complex, which in turn may lead to the friable membrane skeleton and suggested membrane instability related to this disorder. Type I HS spectrin binds approximately 63% as much protein-4.1 as normal spectrin (with equal affinity). This defect does not correlate with splenic function or erythrocyte age in the circulation. However, the approximately 37% reduction in binding of protein-4.1 to HS spectrin approaches the theoretical value of 50% expected in this autosomal dominant disorder. All other type I membrane skeletal interactions (spectrin-syndein, spectrin heterodimer- heterodimer, syndein-band-3) were found to be normal. It would appear therefore that the defective HS spectrin-protein-4.1 interaction in type I hereditary spherocytosis may be the primary molecular defect rather than a secondary phenomena. 相似文献
90.
Molloy K; Goulden N; Lawler M; Cornish J; Oakhill A; Pamphilon D; Potter M; Steward C; Langlands K; Humphries P; McCann SR 《Blood》1996,87(7):3027-3031
Hematopoietic chimerism was analyzed in serial bone marrow samples taken from 28 children following T-cell depleted unrelated donor bone marrow transplants (UD BMT) for acute lymphoblastic leukemia (ALL). Chimeric status was determined by polymerase chain reaction (PCR) of simple tandem repeat (STR) sequences (maximal sensitivity, 0.1%). At least two serial samples were examined in 23 patients. Of these, two had evidence of complete donor engraftment at all times and eight showed stable low level mixed chimerism (MC) (<1% recipient hematopoiesis). All 10 of these patients remain in remission with a minimum follow-up of 24 months. By contrast, 13 patients demonstrated a progressive return of recipient hematopoiesis. Five of these relapsed (4 to 9 months post BMT), one died of cytomegalovirus pneumonitis and seven remain in remission with a minimum follow-up of 24 months. Five children were excluded from serial analysis as two serial samples were not collected before either relapse (3) or graft rejection (2). We conclude that as with sibling transplants, ex vivo T depleted UD BMT in children with ALL is associated with a high incidence of MC. Stable donor engraftment and low level MC always correlated with continued remission. However, detection of a progressive return of recipient cells did not universally correlate with relapse, but highlighted those patients at greatest risk. Serial chimerism analysis by PCR of STRs provides a rapid and simple screening technique for the detection of relapse and the identification of patients with progressive MC who might benefit from detailed molecular analysis for minimal residual disease following matched volunteer UD BMT for childhood ALL. 相似文献