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41.

Purpose

Sepantronium bromide (YM155) is a hydrophilic quaternary compound that cannot be administered orally due to its low oral bioavailability; it is furthermore rapidly eliminated via the kidneys. The current study aims at improving the pharmacokinetic profile of YM155 by its formulation in immunoliposomes that can achieve its enhanced delivery into tumor tissue and facilitate uptake in neuroblastoma cancer cells.

Methods

PEGylated YM155 loaded liposomes composed of DPPC, cholesterol and DSPE-PEG2000 were prepared via passive film-hydration and extrusion method. Targeted (i.e. immuno-)liposomes were prepared by surface functionalization with SATA modified monoclonal anti-disialoganglioside (GD2) antibodies. Liposomes were characterized based on their size, charge, antibody coupling and YM155 encapsulation efficiency, and stability. Flow cytometry analysis and confocal microscopy were performed on IMR32 and KCNR neuroblastoma cell lines. The efficacy of developed formulations were assessed by in-vitro toxicity assays. A pilot pharmacokinetic analysis was performed to assess plasma circulation and tumor accumulation profiles of the developed liposomal formulations.

Results

YM155 loaded immunoliposomes had a size of 170 nm and zeta potential of ?10 mV, with an antibody coupling efficiency of 60% andYM155 encapsulation efficiency of14%. Targeted and control liposomal formulations were found to have similar YM155 release rates in a release medium containing 50% serum. An in-vitro toxicity study on KCNR cells showed less toxicity for immunoliposomes as compared to free YM155. In-vivo pharmacokinetic evaluation of YM155 liposomes showed prolonged blood circulation and significantly increased half-lives of liposomal YM155 in tumor tissue, as compared to a bolus injection of free YM155.

Conclusions

YM155 loaded immunoliposomes were successfully formulated and characterized, and initial in-vivo results show their potential for improving the circulation time and tumor accumulation of YM155.
  相似文献   
42.
While integration has become a central tenet of community‐based care for frail elderly people, little is known about its impact on formal and informal care and their dynamics over time. The aim of this study was therefore to examine how an integrated care intervention for community‐dwelling frail elderly people affects the amount and type of formal and informal care over 12 months as compared to usual care. A quasi‐experimental design with a control group was used. Data regarding formal and informal care were collected from frail elderly patients (n = 207) and informal caregivers (n = 74) with pre/post‐questionnaires. Within‐ and between‐group comparisons and multiple linear regression analyses were performed. The results showed marginal changes over time in the amount of formal and informal care in both integrated care and usual care. However, different associations between changes in formal and informal care were found in integrated and usual care. Most notably, informal caregivers provided more instrumental assistance over time if formal caregivers provided less personal care (and vice versa) in integrated care but not in usual care. These results suggest that integrated care does not necessarily change the contribution of formal or informal care, but changes the interaction between formal (personal care) and informal (instrumental) activities. Implications and recommendations for research and practice are discussed. Trial registration: Current Controlled Trials ISRNT05748494.  相似文献   
43.
OBJECTIVE: Advanced glycation end products (AGEs) are biomarkers of metabolic stress and are thought to contribute to the increase of coronary heart disease (CHD) in diabetes. Tissue autofluorescence is related to the accumulation of AGEs. The aim of the present study was to evaluate the relationship between skin autofluorescence and metabolic burden (hyperglycemia and hyperlipidemia) and its relationship with CHD and mortality. RESEARCH DESIGN AND METHODS: Skin autofluorescence was measured noninvasively with an autofluorescence reader in 48 type 1 and 69 type 2 diabetic patients and 43 control subjects. The presence of CHD was observed at baseline and mortality during a follow-up period of 5 years. RESULTS: Autofluorescence correlated with mean A1C, triglycerides, and LDL. Autofluorescence values further increased with age, microalbuminuria, dialysis treatment, and diabetes duration. Autofluorescence was strongly related to the presence of CHD (odds ratio 7.9) and predicted mortality (3.0). Multivariate analysis showed that autofluorescence was more strongly associated with CHD and mortality compared with A1C, triglycerides, and LDL. CONCLUSIONS: Skin autofluorescence is strongly related to cumulative metabolic burden. Skin autofluorescence seems strongly associated with cardiac mortality and may provide important clinical information for risk assessment.  相似文献   
44.

Background

Nurses are consistently present throughout the rehabilitation of older patients but are apprehensive about performing goal-centred care in the multidisciplinary team.

Objectives

The aim of this review was to explore working interventions on setting goals and working with goals designed for nurses in geriatric rehabilitation, and to describe their distinctive features.

Methods

We performed a scoping review. We searched MEDLINE and CINAHL through August 4, 2021. Search terms related to the following themes: nurses, rehabilitation, geriatric, goal and method. We used snowballing to find additional. From the selected studies, we systematically extracted data on means, materials and the nursing role and summarized them in a narrative synthesis, using intervention component analysis.

Results

The study includes 13 articles, describing 11 interventions which were developed for six different aims: improving multidisciplinary team care; increasing patient centredness; improving disease management by patients; improving the psychological, and emotional rehabilitation; increasing the nursing involvement in rehabilitation; or helping patients to achieve goals. The interventions appeal to four aspects of the nursing profession: assessing self-care skills incorporating patient's preferences; setting goals with patients, taking into account personal needs and what is medically advisable; linking the needs of the patient with multidisciplinary professional treatment and vice versa; and thus, playing an intermediate role and supporting goal achievement.

Conclusions

The interventions show that in goal-centred care, the nurse might play an important unifying role between patients and the multidisciplinary team. With the support of nurses, the patient may become more aware of the rehabilitation process and transfer of ownership of treatment goals from the multidisciplinary team to the patient might be achieved. Not many interventions were found meant to support the nursing role. This may indicate a blind spot in the rehabilitation community to the additional value of its contribution.  相似文献   
45.
Activation of Rap1 by exchange protein activated by cAMP (Epac) promotes cell adhesion and actin cytoskeletal polarization. Pharmacologic activation of Epac-Rap signaling by the Epac-selective cAMP analog 8-pCPT-2′-O-Me-cAMP during ischemia-reperfusion (IR) injury reduces renal failure and application of 8-pCPT-2′-O-Me-cAMP promotes renal cell survival during exposure to the nephrotoxicant cisplatin. Here, we found that activation of Epac by 8-pCPT-2′-O-Me-cAMP reduced production of reactive oxygen species during reoxygenation after hypoxia by decreasing mitochondrial superoxide production. Epac activation prevented disruption of tubular morphology during diethyl maleate–induced oxidative stress in an organotypic three-dimensional culture assay. In vivo renal targeting of 8-pCPT-2′-O-Me-cAMP to proximal tubules using a kidney-selective drug carrier approach resulted in prolonged activation of Rap1 compared with nonconjugated 8-pCPT-2′-O-Me-cAMP. Activation of Epac reduced antioxidant signaling during IR injury and prevented tubular epithelial injury, apoptosis, and renal failure. Our data suggest that Epac1 decreases reactive oxygen species production by preventing mitochondrial superoxide formation during IR injury, thus limiting the degree of oxidative stress. These findings indicate a new role for activation of Epac as a therapeutic application in renal injury associated with oxidative stress.Renal ischemia-reperfusion (IR) injury is an important cause of AKI1 and a significant risk factor for the development of renal dysfunction after kidney transplantation.2 During IR injury, morphologic and functional alterations of the proximal tubular epithelium occur that are linked to the development of renal failure and activation of immune cells via release of proinflammatory cytokines.3Exchange protein activated by cAMP (Epac) is a guanine nucleotide exchange factor for the small GTPase Rap1.4 Activation of Epac by cAMP or by the Epac-selective cAMP analog 8-pCPT-2′-O-Me-cAMP (also referred to as 007) induces functional activation of Rap1.5 Initial studies showed that Epac-Rap signaling enhances cell adhesion by supporting maturation of cell-cell junctions6,7 and promoting integrin-mediated cell-matrix adhesion.8,9 In line with these studies, we recently demonstrated that selective activation of Epac reduces proximal tubular epithelial cell (PTEC) detachment during IR injury using in vitro and in vivo models.10 Activation of Epac-Rap was associated with reduced expression of markers for cellular stress in PTECs. In addition, in vitro cisplatin-induced apoptosis of PTECs could be significantly reduced by activation of Epac and this was also associated with improved adhesion of cells.11 On the basis of these findings, we hypothesized that activation of Epac-Rap signaling may protect against a common cytotoxic event in these injury models.Unbalanced and uncontrolled production of reactive oxygen species (ROS) is an important mediator of cell injury and occurs during cisplatin nephrotoxicity,12 IR injury,13 and renal fibrosis.14 In renal pathology, intracellular ROS can be produced enzymatically such as by NADPH oxidase (NOX) complexes or derive from dysfunctional mitochondrial activity. Mitochondrial ROS production appears to be the driving force behind hypoxia-reoxygenation cell injury15 and cisplatin cytotoxicity.16Here we studied the role of specific proximal tubular activation of Epac and how this protects against renal injury in both in vitro and in vivo models for IR injury. We found that ROS production during reoxygenation after hypoxia was decreased by activation of Epac. Selective proximal tubular activation of Epac by renal targeting of 8-pCPT-2′-O-Me-cAMP conjugated to lysozyme (LZM-007) reduced oxidative stress in an in vivo model for IR injury and significantly decreased IR injury–associated renal failure and tubular damage. Our data show that Epac activation reduces ROS-mediated cellular injury in renal disease and may be a therapeutic strategy for modulation of oxidative stress.  相似文献   
46.

Purpose

The aim of this study was the development of poly(D,L-lactide-co-glycolide) (PLGA) microspheres with controlled porosity, to obtain microspheres that afford continuous release of a macromolecular model compound (blue dextran).

Methods

PLGA microspheres with a size of around 40 μm and narrow size distribution (span value of 0.3) were prepared with a double emulsion membrane emulsification method. Gene expression programming (GEP) analysis was applied to design and formulate a batch of microspheres with controlled porosity that shows continuous release of blue dextran.

Results

Low porous microspheres with a high loading efficiency were formed at high polymer concentrations (30% w/w in the oil phase) and were characterized with a burst release <10% and a three-phasic release profile of blue dextran. Increasing porosity (10% w/w polymer concentrations), a sustained release of blue dextran was obtained albeit with up to 40% of burst release. The desired formulation, calculated by GEP, resulted in microspheres with 72% loading efficiency and intermediate porosity. Blue dextran was indeed released continuously in almost a zero order manner over a period of 3 months after an initial small burst release of 9%.

Conclusions

By fine-tuning the porosity, the release profile of PLGA microspheres for macromolecules can be predicted and changed from a three-phasic to a continuous release.  相似文献   
47.
ObjectiveTo compare the effect of exercises and orthotics with orthotics alone on pain and hand function in patients with first carpometacarpal joint (CMC-1) osteoarthritis (OA) and to predict outcomes on pain and hand function of exercises and orthotics.DesignProspective cohort study with propensity score matching.SettingData collection took place in 13 outpatient clinics for hand surgery and hand therapy in The Netherlands.ParticipantsA consecutive, population-based sample of patients with CMC-1 OA (N=173) was included in this study, of which 84 were matched on baseline demographics and baseline primary outcomes.InterventionsExercises and orthotics versus orthotics alone.Main Outcome MeasuresPrimary outcomes included pain and hand function at 3 months, measured using visual analog scale (VAS, 0-100) and the Michigan Hand Outcomes Questionnaire (MHQ, 0-100).ResultsA larger decrease in VAS pain at rest (11.1 points difference; 95% confidence interval, 1.9-20.3; P=.002) and during physical load (22.7 points difference; 95% confidence interval, 13.6-31.0; P<.001) was found in the exercise + orthotic group compared to the orthotic group. In addition, larger improvement was found for the MHQ subscales pain, work performance, aesthetics, and satisfaction in the exercise + orthotic group. No differences were found on other outcomes. Baseline scores of metacarpophalangeal flexion, presence of scaphotrapeziotrapezoid OA, VAS pain at rest, heavy physical labor, and MHQ total predicted primary outcomes for the total exercise + orthotic group (N=131).ConclusionsNon-surgical treatment of patients with CMC-1 OA should include exercises, since there is a relatively large treatment effect compared to using an orthosis alone. Future research should study exercises and predictors in a more standardized setting to confirm this finding.  相似文献   
48.
Current treatment goals in heart failure (HF) aim to improve both survival and quality of life (QoL) of patients. In this brief communication, we reviewed randomized controlled trials that assessed the impact of pharmacological treatment on QoL, and we discussed some methodological limitations of QoL assessment in HF. Studies that assessed QoL with a disease-specific questionnaire were included. We found that at present there is a paradox in HF treatment. Life prolonging therapies, such as angiotensin-converting-enzyme-inhibitors, and angiotensin receptor blockers improve modestly or only delay the progressive worsening of QoL in HF. Treatment with beta blockers does not affect QoL in any way. However, this neutral effect of beta blockers may also be due to some methodological limitations, such as the small number of patients included in beta blocker trials or the short duration of follow-up. Disease-specific questionnaires may also have some limitations, e.g. are not sensitive enough to detect small changes in QoL. On the other hand, therapies that significantly improve QoL in HF (e.g. inotropic agents) do not seem beneficial in relation to survival. We conclude that QoL in HF remains an open field, in which new therapies but also clarification of methodology is required. In the mean time, the use of life prolonging therapies appears as a safe measure to modestly improve or maintain QoL.  相似文献   
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