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101.
This study assessed the seroprevalence of varicella antibodies in children and adolescents in Spain and evaluated the reliability of two methods for detecting susceptible individuals: (1) parental-reported history of varicella and (2) medically-documented histories maintained by the pediatrician. A total of 186 children (6 to 15 years of age) were recruited in 13 pediatric offices of Valencia, Spain. A brief case report form was completed including previous history of varicella referred by the parents, and a 5 mL blood sample was obtained. The pediatrician medical file was reviewed for antecedent of varicella. The overall prevalence of varicella antibodies was 84% and 88% in the 6-9 years and 10-15 years age brackets, respectively. The predictive value of a negative history of varicella disease was 48% by parental recall (52% "false negative"), and only 26% by medical record (74% "false negative"). However, the positive predictive value of a positive parental reported history or a positive medically-documented history was 95%. The most effective strategy for varicella vaccination of older children and adolescents in Spain will be to immunize those individuals with a lack of positive (unknown or negative) history of disease.  相似文献   
102.
There is a global movement for people with a disability towards person‐centred practices with opportunities for self‐determination and choice. Person‐centred approaches may involve individual funding (IF) for the purchase of required support. A shift to a person‐centred model and IF should allow people with a disability and their carers greater choice in therapy access. However, individuals who live in rural and remote areas have less choice and access to therapy services than their metropolitan counterparts. Drawing on data from a larger study into therapy service delivery in a rural and remote area of New South Wales, Australia, this study describes some benefits and barriers to using IF to access therapy services in rural areas. Ten carers and 60 service providers participated in audio‐recorded focus groups and individual interviews during which IF was discussed. Transcribed data were analysed using thematic analysis and constant comparison. Greater access to and choice of therapy providers were identified as benefits of IF. Four barriers were identified: (i) lack of information and advice; (ii) limited local service options and capacity; (iii) higher costs and fewer services and (iv) complexity of self‐managing packages. A range of strategies is required to address the barriers to using IF in rural and remote areas. Carers indicated a need for: accessible information; a local contact person for support and guidance; adequate financial compensation to offset additional travel expenses and coordinated eligibility and accountability systems. Service providers required: coordinated cross‐sector approaches; local workforce planning to address therapist shortages; certainty around service viability and growth; clear policies and procedures around implementation of IF. This study highlights the need for further discussion and research about how to overcome the barriers to the optimal use of an IF model for those living in rural and remote areas.  相似文献   
103.

Background

An intervention’s success depends on how participants interact with it in local settings. Process evaluation examines these interactions, indicating why an intervention was or was not effective, and how it (and similar interventions) can be improved for better contextual fit. This is particularly important for innovative trials like Supporting Policy In health with Research: an Intervention Trial (SPIRIT), where causal mechanisms are poorly understood. SPIRIT was testing a multi-component intervention designed to increase the capacity of health policymakers to use research.

Methods

Our mixed-methods process evaluation sought to explain variation in observed process effects across the six agencies that participated in SPIRIT. Data collection included observations of intervention workshops (n = 59), purposively sampled interviews (n = 76) and participant feedback forms (n = 553). Using a realist approach, data was coded for context-mechanism-process effect configurations (retroductive analysis) by two authors.

Results

Intervention workshops were very well received. There was greater variation of views regarding other aspects of SPIRIT such as data collection, communication and the intervention’s overall value. We identified nine inter-related mechanisms that were crucial for engaging participants in these policy settings: (1) Accepting the premise (agreeing with the study’s assumptions); (2) Self-determination (participative choice); (3) The Value Proposition (seeing potential gain); (4) ‘Getting good stuff’ (identifying useful ideas, resources or connections); (5) Self-efficacy (believing ‘we can do this!’); (6) Respect (feeling that SPIRIT understands and values one’s work); (7) Confidence (believing in the study’s integrity and validity); (8) Persuasive leadership (authentic and compelling advocacy from leaders); and (9) Strategic insider facilitation (local translation and mediation). These findings were used to develop tentative explanatory propositions and to revise the programme theory.

Conclusion

This paper describes how SPIRIT functioned in six policy agencies, including why strategies that worked well in one site were less effective in others. Findings indicate a complex interaction between participants’ perception of the intervention, shifting contextual factors, and the form that the intervention took in each site. Our propositions provide transferable lessons about contextualised areas of strength and weakness that may be useful in the development and implementation of similar studies.
  相似文献   
104.
Healthcare technology is a two-edged sword - it offers new and better treatment to a wider range of people and, at the same time, is a major driver of increasing costs in health systems. Many countries have developed sophisticated systems of health technology assessment (HTA) to inform decisions about new investments in new healthcare interventions. In this paper, we question whether HTA is also the appropriate framework for guiding or informing disinvestment decisions. In exploring the issues related to disinvestment, we first discuss the various HTA frameworks which have been suggested as a means of encouraging or facilitating disinvestment. We then describe available means of identifying candidates for disinvestment (comparative effectiveness research, clinical practice variations, clinical practice guidelines) and for implementing the disinvestment process (program budgeting and marginal analysis (PBMA) and related techniques). In considering the possible reasons for the lack of progress in active disinvestment, we suggest that HTA is not the right framework as disinvestment involves a different decision making context. The key to disinvestment is not just what to stop doing but how to make it happen - that is, decision makers need to be aware of funding disincentives.  相似文献   
105.
ABSTRACT

Introduction: Lung cancer is the leading cancer-related cause of death worldwide. The introduction of immune checkpoint inhibitors (ICIs) for the treatment of lung cancer has significantly improved the outcome of these patients. Pembrolizumab, a monoclonal IgG4-kappa antibody against programmed-death-1 (PD-1) protein, nowadays represents a standard of care for NSCLC patients. Although it has a favorable toxicity profile, some immune-related adverse events (irAEs) can be life-threatening, therefore its knowledge may help to optimize the care of these patients.

Areas covered: The authors review data regarding the efficacy and safety of pembrolizumab from the most relevant clinical trials as well as toxicities reported in the clinical use. Special considerations of use in special populations will be noted. Finally, its toxicity profile will be compared with other ICIs used in NSCLC.

Expert opinion: In the scenario of NSCLC, pembrolizumab shows a favorable safety profile with less than 10% serious immune-related adverse events (irAEs) when used in monotherapy and without adding relevant extra-toxicity to chemotherapy when used in combination. Monotherapy with pembrolizumab is associated with better health-related quality of life than chemotherapy. Early recognition and appropriate treatment of irAEs is of prime importance as most are reversible if correctly managed. Rechallenge with pembrolizumab is frequently feasible.  相似文献   
106.
Microtubules and tubulin are major dynamic and structural cellular components that play a key role in several cell functions, including division, signalling and intracellular trafficking. Normal epithelial cells have a highly structured, rigid cytoskeletal network that is compatible with cell motility. Thus, tubulin and microtubules are compelling cellular targets for chemotherapy. In fact, among anticancer agents, those that target microtubules constitute one of the most effective classes of chemotherapeutics in cancer. The list of compounds that target either tubulin or microtubules is extensive and consists of chemically unique compounds that bind to the tubulin dimers and destabilize microtubules (Vinca alkaloids) and those that bind to the microtubule polymer and stabilize microtubules (taxanes). Tumour-induced angiogenesis, the formation of new capillaries from existing blood vessels, and epithelial-mesenchymal transition are two steps that are critical for both tumour growth and metastatic spread. Three possible mechanisms of action are described with vinflunine, the new-generation Vinca alkaloid to arrive in clinical practice are as follows: it acts against tubulin and microtubules, disrupts newly formed blood vessels and seems to be able to reduce the metastatic process as shown in preclinical studies. These findings support the hypothesis that vinflunine, by blocking microtubule functions that contribute to cell shape, polarization, migration and other processes, might be responsible not only for tumour-cytostatic but also for specific antiangiogenic or antiepithelial-mesenchymal transition effects.  相似文献   
107.
OBJECTIVE: To gather information about views of members of the general public about access to High Cost Medications (HCMs) in public hospitals. METHODS: A structured questionnaire was administered to members of the general public. Individuals were approached in train stations, shopping centres and different venues in the Sydney metropolitan area. People were eligible to answer the survey if they were: over 18 years of age, Australian permanent residents and able to complete the questionnaire in English. RESULTS: Two hundred people completed the survey. Of these 56% were females, 47% were married, 84% spoke English at home, 88% were working either full-time or part-time, 61% had a university degree, 27% had a household annual income greater than 100,000 dollars and 68% had private health insurance. Participants considered factors such as treatment outcomes, quality of life and current health status when determining who should have access to HCMs. Participants wanted resources to be allocated to provide the 'greatest benefit to the greatest number of people'. Almost half the respondents did not want direct involvement in decision-making, however, 38% did. CONCLUSIONS: The results offered support for indirect involvement through the development of a process to involve community members in discussion on policy on the provision of treatment and services within health-care institutions and specifically, to seek the views of members of the public on the provision of HCMs and expensive services within public hospitals.  相似文献   
108.
Current methods for sustainable control of avian coccidiosis, whether by prophylactic medication or parasite vaccination, are suboptimal. In this study, we describe an alternative immunization strategy against Eimeria tenella infection using parasite antigen (Ag)-loaded dendritic cells (DCs), or their derived exosomes, in the absence of free Ag. CD45+ intestinal DCs were isolated from E. tenella-infected chickens and loaded ex vivo with an extract of sporozoites as parasite Ag. Extracellular vesicles purified from the Ag-pulsed DCs expressed surface proteins associated with DC-derived exosomes, including major histocompatibility complex proteins (MHC I and MHC II), CD80, flotillin, and heat shock protein (HSP70). Following intramuscular immunization of chickens with Ag-pulsed DCs or Ag-pulsed DC-derived exosomes, Ag-containing cells were observed diffusely localized in the lymphoid tissue and concentrated in germinal centers of caecal tonsils, and restricted to germinal centers (GC) in the spleen. Chickens immunized with pulsed DCs or exosomes exhibited (a) higher numbers of caecal tonsil and spleen cells expressing IgG and/or IgA antibodies that were reactive with E. tenella Ag, (b) greater numbers of IL-2-, IL-16-, and IFN-γ-producing cells, and (c) higher E. tenella Ag-driven cell proliferation, compared with chickens immunized with Ag in the absence of DCs or exosomes. Chickens immunized with Ag-pulsed DCs or Ag-pulsed DC-derived exosomes and subsequently given a live E. tenella challenge infection at 10 d post-immunization displayed (a) increased body weight gains, (b) decreased feed conversion ratios, (c) reduced fecal oocyst shedding, (d) diminished intestinal lesions, and (e) lower mortality, compared with animals given Ag alone. This is the first demonstration of Ag-specific protective immunity against avian coccidiosis using parasite Ag-loaded DCs or DC-derived exosomes.  相似文献   
109.

Purpose

We retrospectively examined the potential effect on overall survival (OS) of delaying radiotherapy to administer neoadjuvant therapy in unresected glioblastoma patients.

Patients and methods

We compared OS in 119 patients receiving neoadjuvant therapy followed by standard treatment (NA group) and 96 patients receiving standard treatment without neoadjuvant therapy (NoNA group). The MaxStat package of R identified the optimal cut-off point for waiting time to radiotherapy.

Results

OS was similar in the NA and NoNA groups. Median waiting time to radiotherapy after surgery was 13 weeks for the NA group and 4.2 weeks for the NoNA group. The longest OS was attained by patients who started radiotherapy after 12 weeks and the shortest by patients who started radiotherapy within 4 weeks (12.3 vs 6.6 months) (P?=?0.05). OS was 6.6 months for patients who started radiotherapy before the optimal cutoff of 6.43 weeks and 19.1 months for those who started after this time (P?=?0.005). Patients who completed radiotherapy had longer OS than those who did not, in all 215 patients and in the NA and NoNA groups (P?=?0.000). In several multivariate analyses, completing radiotherapy was a universally favorable prognostic factor, while neoadjuvant therapy was never identified as a negative prognostic factor.

Conclusion

In our series of unresected patients receiving neoadjuvant treatment, in spite of the delay in starting radiotherapy, OS was not inferior to that of a similar group of patients with no delay in starting radiotherapy.
  相似文献   
110.
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