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111.
The sustained and localized delivery of monoclonal antibodies has become highly relevant, because of the increasing number of investigated local delivery applications in recent years. As the local delivery of antibodies is associated with high technological hurdles, very few successful approaches have been reported in the literature so far. Alginate-based delivery systems were previously described as promising sustained release formulations for monoclonal antibodies (mAbs). In order to further investigate their applicability, a single-dose animal study was conducted to compare the biocompatibility, the pharmacokinetics and the bioavailability of a human monoclonal antibody liquid formulation with two alginate-based sustained delivery systems after subcutaneous administration in rats. 28 days after injection, the depot systems were still found in the subcutis of the animals. A calcium cross-linked alginate formulation, which was injected as a hydrogel, was present as multiple compartments separated by subcutaneous tissue. An in situ forming alginate formulation was recovered as a single compact and cohesive structure. It can be assumed that the multiple compartments of the hydrogel formulation led to almost identical pharmacokinetic profiles for all tested animals, whereas the compact nature of the in situ forming system resulted in large interindividual variations in pharmacokinetics. As compared to the liquid formulation the hydrogel formulations led to lower mAb serum levels, and the in situ forming system to a shift in the time to reach the maximum mAb serum concentration (Tmax) from 2 to 4 days. Importantly, it was shown that after 28 days only marginal amounts of residual mAb were present in the alginate matrix and in the tissue at the injection site indicating nearly complete release. In line with this finding, systemic drug bioavailability was not affected by using the controlled release systems. This study successfully demonstrates the suitability and underlines the potential of polyanionic systems for local and controlled mAb delivery.  相似文献   
112.
Studies suggest that tau deposition starts in the anterolateral entorhinal cortex (EC) with normal aging, and that the presence of β-amyloid (Aβ) facilitates its spread to neocortex, which may reflect the beginning of Alzheimer''s disease (AD). Functional connectivity between the anterolateral EC and the anterior-temporal (AT) memory network appears to drive higher tau deposition in AT than in the posterior-medial (PM) memory network. Here, we investigated whether this differential vulnerability to tau deposition may predict different cognitive consequences of EC, AT, and PM tau. Using 18F-flortaucipir (FTP) and 11C-Pittsburgh compound-B (PiB) positron emission tomography (PET) imaging, we measured tau and Aβ in 124 cognitively normal human older adults (74 females, 50 males) followed for an average of 2.8 years for prospective cognition. We found that higher FTP in all three regions was individually related to faster memory decline, and that the effects of AT and PM FTP, but not EC, were driven by Aβ+ individuals. Moreover, when we included all three FTP measures competitively in the same model, only AT FTP significantly predicted memory decline. Our data support a model whereby tau, facilitated by Aβ, transits from EC to cortical regions that are most closely associated with the anterolateral EC, which specifically affects memory in the initial stage of AD. Memory also appears to be affected by EC tau in the absence of Aβ, which may be less clinically consequential. These findings may provide clarification of differences between normal aging and AD, and elucidate the transition between the two stages.SIGNIFICANCE STATEMENT Tau and β-amyloid (Aβ) are hallmarks of Alzheimer''s disease (AD) but are also found in cognitively normal people. It is unclear whether, and how, this early deposition of tau and Aβ may affect cognition in normal aging and the asymptomatic stage of AD. We show that tau deposition in the entorhinal cortex (EC), which is common in advanced age, predicts memory decline in older adults independent of Aβ, likely reflecting normal, age-related memory loss. In contrast, tau in anterior-temporal (AT) regions is most predictive of memory decline in Aβ+ individuals. These data support the idea that tau preferentially spreads to specific cortical regions, likely through functional connections, which plays a primary role in memory decline in the early stage of AD.  相似文献   
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ObjectiveA recent study suggested that the anti-inflammatory effect of immunonutrition starts after only two d. We therefore investigated the effect of an immunoenriched oral diet administered for three d preoperatively.MethodsIn this prospective, randomized, double-blind, placebo-controlled study, well-nourished patients (Nutrition Risk Screening 2002 <3) with gastrointestinal cancer who were scheduled for major elective abdominal cancer surgery were randomly assigned to either 750 mL of an immunoenriched formula (IEF group) or 750 mL of an isocaloric, isonitrogenous placebo diet (Con group) for 3 consecutive d preoperatively.ResultsA total of 108 patients (IEF group: n = 55; Con group: n = 53) were randomized. The two groups were comparable for all baseline and surgical characteristics. The overall mortality was 2.8% and not significantly different between the two groups (IEF group: 3.6% vs. Con group: 1.9%, P = 1.00). Intention-to-treat analysis showed no difference for the incidence of postoperative overall (IEF group: 29% vs. Con group: 30%; P = 1.00) and infectious (IEF group: 15% vs. Con group: 17%; P = 0.79) complications. Length of hospital stay was 12 ± 4.9 d in the IEF group and 11.6 ± 5.3 d in the Con group (P = 0.68).ConclusionsPreoperative oral supplementation with an immunoenriched diet for 3 d preoperatively did not improve postoperative outcome compared with the placebo in well-nourished patients with elective gastrointestinal cancer surgery.  相似文献   
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Of the 58,186 coronavirus deaths among adults in England during March–December 2020, 77% occurred in hospitals, 93% were in patients >60 years, and 91% occurred within 28 days of positive specimen. Cumulative mortality rates were highest among persons of Black, Asian, other, or mixed ethnicities and in socioeconomically deprived areas.  相似文献   
119.

Objective

To evaluate the cost-effectiveness of financial incentives for human immunodeficiency virus (HIV) viral suppression compared to standard of care.

Study Design

Mathematical model of 2-year intervention offering financial incentives ($70 quarterly) for viral suppression (<400 copies/ml3) based on the HPTN 065 clinical trial with HIV patients in the Bronx, NY and Washington, D.C.

Methods

A disease progression model with HIV transmission risk equations was developed following guidelines from the Second Panel on Cost-Effectiveness in Health and Medicine. We used health care sector and societal perspectives, 3% discount rate, and lifetime horizon. Data sources included trial data (baseline N = 16,208 patients), CDC HIV Surveillance data, and published literature. Outcomes were costs (2017 USD), quality-adjusted life years (QALYs), HIV infections prevented, and incremental cost-effectiveness ratio (ICER).

Results

Financial incentives for viral suppression were estimated to be cost-saving from a societal perspective and cost-effective ($49,877/QALY) from a health care sector perspective. Compared to the standard of care, financial incentives gain 0.06 QALYs and lower discounted lifetime costs by $4210 per patient. The model estimates that incentivized patients transmit 9% fewer infections than the standard-of-care patients. In the sensitivity analysis, ICER 95% credible intervals ranged from cost-saving to $501,610/QALY with 72% of simulations being cost-effective using a $150,000/QALY threshold. Modeling results are limited by uncertainty in efficacy from the clinical trial.

Conclusions

Financial incentives, as used in HTPN 065, are estimated to improve quality and length of life, reduce HIV transmissions, and save money from a societal perspective. Financial incentives offer a promising option for enhancing the benefits of medication in the United States.  相似文献   
120.
This report describes a patient with light chain myeloma and acute renal injury. Serum kappa free light chain (FLC) was extremely elevated, >33,000 mg/dL. Treatment with therapeutic plasma exchange (TPE) started day 2 for biopsy‐confirmed cast nephropathy. Bortezomib‐containing chemotherapy was initiated on day 5, and hemodialysis for tumor lysis syndrome on day 7. TPE alone decreased kappa FLC >70% by day 5, indicating direct FLC removal was successful in this patient. A total of 25 TPE procedures were performed in a 31‐day hospitalization. Hemodialysis was discontinued after 3 months, and the patient's renal function and kappa FLC remain stable. Although the use of TPE for FLC removal is controversial, recent evidence supports its use as adjuvant therapy for acute renal injury secondary to myeloma cast nephropathy. TPE can be effective for rapidly reducing FLC; however, several TPE procedures might be required to reduce the risk of hemodialysis dependency.  相似文献   
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