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91.

BACKGROUND

An increasing number of hospitals and health systems utilize social media to allow users to provide feedback and ratings. The correlation between ratings on social media and more conventional hospital quality metrics remains largely unclear, raising concern that healthcare consumers may make decisions on inaccurate or inappropriate information regarding quality.

OBJECTIVES

The purpose of this study was to examine the extent to which hospitals utilize social media and whether user-generated metrics on Facebook® correlate with a Hospital Compare® metric, specifically 30-day all cause unplanned hospital readmission rates.

DESIGN AND PARTICIPANTS

This was a retrospective cross-sectional study conducted among all U.S. hospitals performing outside the confidence interval for the national average on 30-day hospital readmission rates as reported on Hospital Compare. Participants were 315 hospitals performing better than U.S. national rate on 30-day readmissions and 364 hospitals performing worse than the U.S. national rate.

MAIN MEASURES

The study analyzed ratings of hospitals on Facebook’s five-star rating scale, 30-day readmission rates, and hospital characteristics including beds, teaching status, urban vs. rural location, and ownership type.

KEY RESULTS

Hospitals performing better than the national average on 30-day readmissions were more likely to use Facebook than lower-performing hospitals (93.3 % vs. 83.5 %; p < 0.01). The average rating for hospitals with low readmission rates (4.15 ± 0.31) was higher than that for hospitals with higher readmission rates (4.05 ± 0.41, p < 0.01). Major teaching hospitals were 14.3 times more likely to be in the high readmission rate group. A one-star increase in Facebook rating was associated with increased odds of the hospital belonging to the low readmission rate group by a factor of 5.0 (CI: 2.6–10.3, p <  0.01), when controlling for hospital characteristics and Facebook-related variables.

CONCLUSIONS

Hospitals with lower rates of 30-day hospital-wide unplanned readmissions have higher ratings on Facebook than hospitals with higher readmission rates. These findings add strength to the concept that aggregate measures of patient satisfaction on social media correlate with more traditionally accepted measures of hospital quality.KEY WORDS: Performance measurement, Patient satisfaction, Consumer health informatics  相似文献   
92.
Brachyspira hyodysenteriae colonizes the pig colon, resulting in mucohemorrhagic diarrhea and growth retardation. Fecal mucus is a characteristic feature of swine dysentery; therefore, we investigated how the mucin environment changes in the colon during infection with B. hyodysenteriae and how these changes affect this bacterium''s interaction with mucins. We isolated and characterized mucins, the main component of mucus, from the colon of experimentally inoculated and control pigs and investigated B. hyodysenteriae binding to these mucins. Fluorescence microscopy revealed a massive mucus induction and disorganized mucus structure in the colon of pigs with swine dysentery. Quantitative PCR (qPCR) and antibody detection demonstrated that the mucus composition of pigs with swine dysentery was characterized by de novo expression of MUC5AC and increased expression of MUC2 in the colon. Mucins from the colon of inoculated and control pigs were isolated by two steps of isopycnic density gradient centrifugation. The mucin densities of control and inoculated pigs were similar, whereas the mucin quantity was 5-fold higher during infection. The level of B. hyodysenteriae binding to mucins differed between pigs, and there was increased binding to soluble mucins isolated from pigs with swine dysentery. The ability of B. hyodysenteriae to bind, measured in relation to the total mucin contents of mucus in sick versus healthy pigs, increased 7-fold during infection. Together, the results indicate that B. hyodysenteriae binds to carbohydrate structures on the mucins as these differ between individuals. Furthermore, B. hyodysenteriae infection induces changes to the mucus niche which substantially increase the amount of B. hyodysenteriae binding sites in the mucus.  相似文献   
93.
Current treatments to control pathological or unwanted immune responses often use broadly immunosuppressive drugs. New approaches to induce antigen-specific immunological tolerance that control both cellular and humoral immune responses are desirable. Here we describe the use of synthetic, biodegradable nanoparticles carrying either protein or peptide antigens and a tolerogenic immunomodulator, rapamycin, to induce durable and antigen-specific immune tolerance, even in the presence of potent Toll-like receptor agonists. Treatment with tolerogenic nanoparticles results in the inhibition of CD4+ and CD8+ T-cell activation, an increase in regulatory cells, durable B-cell tolerance resistant to multiple immunogenic challenges, and the inhibition of antigen-specific hypersensitivity reactions, relapsing experimental autoimmune encephalomyelitis, and antibody responses against coagulation factor VIII in hemophilia A mice, even in animals previously sensitized to antigen. Only encapsulated rapamycin, not the free form, could induce immunological tolerance. Tolerogenic nanoparticle therapy represents a potential novel approach for the treatment of allergies, autoimmune diseases, and prevention of antidrug antibodies against biologic therapies.Undesired immunogenicity can have a profound impact on human health. Allergies, including allergic asthma and severe food allergies, affect ∼20% of the population, and the prevalence has been steadily increasing over the past several decades (1). The prevalence of autoimmune diseases, including multiple sclerosis and type 1 diabetes, is ∼4.5% (2). Unwanted immunogenicity can also affect both efficacy and safety of biologic drugs (3), particularly in the case of protein replacement therapies for the treatment of genetic deficiencies, such as hemophilia A (4) and Pompe Disease (5). Immunomodulatory agents commonly used to control immunogenicity are often broadly immunosuppressive and typically require chronic administration that can lead to reactivation of latent pathogens, development of tumors, and opportunistic infections (6, 7). Therefore, antigen-specific, durable tolerogenic therapy would be highly desirable from an efficacy and safety perspective.Multiple techniques for antigen-specific immunotherapy have been described, although only allergen immunotherapy, wherein low doses of antigen are delivered in the absence of immunomodulating agents, is currently used in the clinic (1). Experimental approaches have included oral administration of antigen, high dose tolerance, and the use of altered peptide ligands (8). Although these methods have been successful in preclinical models, translation to human clinical trials has been largely disappointing (8). Alternative strategies to leverage tolerogenic programming associated with apoptotic cells include conjugating antigen to splenocytes (912) or synthetic microparticles (13, 14) or targeting antigen to the surface of red blood cells (15). Other approaches include loading particles with MHC complexes that present relevant peptides in the absence of costimulation (16, 17), liposomal copresentation of antigen with a ligand specific for the negative signaling receptor CD22 on B cells (18), codelivery of peptide antigen with an aryl hydrocarbon receptor agonist (19), and cotreatment with pharmacological agents, such as methotrexate (20). A major concern for antigen immunotherapy is the ability to induce and maintain tolerance in the presence of proinflammatory stimuli caused by tissue stress, injury, or concurrent infections. We sought to develop an antigen-specific tolerogenic technology that could control both T-cell– and B-cell–mediated immunity and that was durable over time and to multiple challenges with the antigen, even in the presence of strong innate immune stimulants.Dendritic cells (DCs) are an attractive target for immunotherapies due to their central role in antigen presentation to T cells and their ability to induce and control regulatory responses to secure self-tolerance (2125). Thomson and colleagues (26, 27) demonstrated that treating DCs with rapamycin, an inhibitor of the mTOR pathway, induces a tolerogenic DC phenotype capable of inducing Treg differentiation and antigen-specific immune tolerance that is resistant to the proinflammatory cascade triggered by TLR signaling. However, conventional therapy with free rapamycin requires chronic systemic administration, resulting in broad immunosuppression due to its direct effect on lymphocytes (28), whereas low doses of rapamycin may paradoxically augment effector T-cell memory (29). Thus, it would be desirable to transiently target rapamycin’s effects to DCs and other antigen-presenting cells (APCs) at the time of antigen encounter. Nanoparticles (NPs) are an ideal mechanism to deliver antigen (16, 30, 31) and drugs (32) to APCs, as these cells are keyed to capture and internalize nanoparticulates such as viruses.Here we describe the development of tolerogenic NPs (tNPs) using materials and compounds that have been well validated in the clinic. These self-assembling, biodegradable poly(lactide-coglycolide) (PLGA) tNPs containing either protein or peptide antigens and rapamycin are capable of inducing durable antigen-specific tolerance that control adaptive immune responses and withstand multiple immunogenic challenges with antigen. We demonstrate that either s.c. or i.v. administration of tNPs inhibits the activation of antigen-specific CD4+ and CD8+ T cells and B cells while inducing antigen-specific Tregs and Bregs. Swiss Jack Lambert (SJL) mice immunized with the myelin proteolipid protein 139–151 peptide in complete Freud’s adjuvant (PLP139–151/CFA) and treated therapeutically with a single dose of tNPs at the peak of disease are completely protected from developing relapsing paralysis. In hemophilia A animals, administration of tNP before or after the establishment of an anti-factor VIII (FVIII) antibody response led to a significant reduction of the neutralizing antibody response against FVIII. Treatment of mice with tNP prevents both cellular and humoral immunity even in the presence of potent TLR agonists. These effects are dependent on the presence of the encapsulated rapamycin (not free in solution).  相似文献   
94.
95.
96.

Purpose

Minimally invasive cochlear implantation is a surgical technique which requires drilling a canal from the mastoid surface toward the basal turn of the cochlea. The choice of an appropriate drilling strategy is hypothesized to have significant influence on the achievable targeting accuracy. Therefore, a method is presented to analyze the contribution of the drilling process and drilling tool to the targeting error isolated from other error sources.

Methods

The experimental setup to evaluate the borehole accuracy comprises a drill handpiece attached to a linear slide as well as a highly accurate coordinate measuring machine (CMM). Based on the specific requirements of the minimally invasive cochlear access, three drilling strategies, mainly characterized by different drill tools, are derived. The strategies are evaluated by drilling into synthetic temporal bone substitutes containing air-filled cavities to simulate mastoid cells. Deviations from the desired drill trajectories are determined based on measurements using the CMM.

Results

Using the experimental setup, a total of 144 holes were drilled for accuracy evaluation. Errors resulting from the drilling process depend on the specific geometry of the tool as well as the angle at which the drill contacts the bone surface. Furthermore, there is a risk of the drill bit deflecting due to synthetic mastoid cells.

Conclusions

A single-flute gun drill combined with a pilot drill of the same diameter provided the best results for simulated minimally invasive cochlear implantation, based on an experimental method that may be used for testing further drilling process improvements.  相似文献   
97.
Adaptive muscle activation strategies following a massive rotator cuff tear (MRCT) are inadequately understood, and the relationship among muscles during everyday activities has not been considered. Thirteen healthy subjects comprised the control group, and 11 subjects with a MRCT the patient group. Upper limb function was assessed using the Functional Impairment test‐hand, neck, shoulder, and arm (FIT‐HaNSA). Electromyography (EMG) was recorded from 13 shoulder muscles, comprising five muscle groups, during a shelf‐lifting task. Mean FIT‐HaNSA scores were significantly lower in MRCT patients (p ≤ 0.001), reflecting a severe functional deficit. In MRCT patients, EMG signal amplitude was significantly higher for the biceps brachii‐brachioradialis (p < 0.001), upper trapezius‐serratus anterior (p = 0.025), muscle groups and for the latissimus dorsi (p = 0.010), and teres major (p = 0.007) muscles. No significant differences in the correlation among muscle groups were identified, pointing to an unchanged neuromuscular strategy following a tear. In MRCT patients, a reorganization of muscle activation strategy along the upper limb kinetic chain is aimed at reducing demand on the glenohumeral joint. Increased activation of the latissimus dorsi and teres major muscles is an attempt to compensate for the deficient rotator cuff. Re‐education towards an alternate neuromuscular control strategy appears necessary to restore function. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1140–1146, 2012  相似文献   
98.

Purpose

The main purpose of this study was to assess the reliability and validity of the Iranian version of the Epworth Sleepiness Scale (ESS-IR).

Methods

This was a cross-sectional study of 507 suspicious patients either to obstructive sleep apnea (n?=?466) or narcolepsy (n?=?41) in order to carry out a psychometric evaluation of the ESS-IR by performing reliability, validity, and responsiveness analyses. Reliability of the ESS-IR was assessed by internal consistency and test–retest reliability. Validity of the instrument was assessed using several statistical approaches including construct validity (exploratory factor analysis), discriminant validity, and criterion validity. Responsiveness of the ESS-IR was assessed by comparing the ESS-IR total score before and after 6–9 months of continues positive airway pressure (CPAP) treatment in 16 patients with obstructive sleep apnea (OSA).

Results

The ESS-IR had an acceptable internal consistency and test–retest reliability. Factor analysis in both groups showed a two-factor solution for the ESS-IR, but the first factor showed statistically significant loads in all items. In addition, the ESS-IR discriminated well between patients with and without OSA. There is a fair correlation between the ESS-IR total score and multiple sleep latency test results that is not significant at all. Finally, the ESS-IR was found to be responsive to change where the total score was significantly decreased after CPAP treatment (P?<?0.001).

Conclusion

The findings suggest that the ESS-IR is a reliable and valid measure for evaluating daytime sleepiness and now can be used in research and clinical settings in Iran.  相似文献   
99.
100.
Cisplatin and other DNA-damaging chemotherapeutics are widely used to treat a broad spectrum of malignancies. However, their application is limited by both intrinsic and acquired chemoresistance. Most mutations that result from DNA damage are the consequence of error-prone translesion DNA synthesis, which could be responsible for the acquired resistance against DNA-damaging agents. Recent studies have shown that the suppression of crucial gene products (e.g., REV1, REV3L) involved in the error-prone translesion DNA synthesis pathway can sensitize intrinsically resistant tumors to chemotherapy and reduce the frequency of acquired drug resistance of relapsed tumors. In this context, combining conventional DNA-damaging chemotherapy with siRNA-based therapeutics represents a promising strategy for treating patients with malignancies. To this end, we developed a versatile nanoparticle (NP) platform to deliver a cisplatin prodrug and REV1/REV3L-specific siRNAs simultaneously to the same tumor cells. NPs are formulated through self-assembly of a biodegradable poly(lactide-coglycolide)-b-poly(ethylene glycol) diblock copolymer and a self-synthesized cationic lipid. We demonstrated the potency of the siRNA-containing NPs to knock down target genes efficiently both in vitro and in vivo. The therapeutic efficacy of NPs containing both cisplatin prodrug and REV1/REV3L-specific siRNAs was further investigated in vitro and in vivo. Quantitative real-time PCR results showed that the NPs exhibited a significant and sustained suppression of both genes in tumors for up to 3 d after a single dose. Administering these NPs revealed a synergistic effect on tumor inhibition in a human Lymph Node Carcinoma of the Prostate xenograft mouse model that was strikingly more effective than platinum monotherapy.Advances in genomics and cell biology have highlighted the heterogeneity and complexity of cancer. It is generally accepted that cancer is usually the result of a combination of interconnected disease pathways that may not be treated effectively with 1D therapeutic mechanisms (1). The inhibition of a pathway by a single-drug therapy often results in the emergence of drug resistance and tumor relapse, largely because of pathway redundancy, cross-talk, compensatory and neutralizing actions, and antitarget activities that commonly occur with single-drug cancer therapy (2). In some cases, relapse can result in the emergence of phenotypically distinct and possibly more virulent tumors. For example, treatment of prostatic adenocarcinoma with androgen ablation therapies, such as abiraterone or enzalutamide, results in the development of abiraterone or enzalutamide refractory castration-resistant prostate cancer that is phenotypically nonadenocarcinoma and represents a rare and often lethal form of prostate cancer with a neuroendocrine phenotype (3).Platinum agents are among the most widely used cytotoxic agents for cancer therapy. Cisplatin and other DNA adduct-forming chemotherapeutics cause DNA damage as their primary mechanism of cellular cytotoxicity. However, several cellular pathways are activated in response to their interaction with DNA, which include DNA repair pathways that remove the damage and translesion DNA synthesis (TLS) by specialized DNA polymerases that helps the cells tolerate the DNA damage (4, 5). The Rev1/Rev3L/Rev7-dependent error-prone TLS pathway has been shown to play an important role in cisplatin-induced mutations that improve the capacity of tumor cells to either repair or tolerate DNA damage, resulting in acquired chemoresistance (6). Rev1 is a translesion DNA polymerase, while Rev3 is the catalytic subunit of the translesion DNA polymerase Polζ (Rev3L/Rev7). Recent studies using mouse lymphoma and lung cancer models have shown that the suppression of error-prone TLS activity in mammalian cells by knocking down Rev1 or Rev3L can inhibit drug-induced mutagenesis so that relapsed tumors remain sensitive to subsequent treatment (6, 7). It has been suggested that combining conventional chemotherapy with newly emerging siRNA therapeutics could be a promising strategy for improving the efficacy of chemotherapy through additive or synergistic effects (8).Since the discovery of RNAi, synthetic siRNA has emerged as a class of attractive therapeutics for treatment of various diseases, including cancer (9, 10). Given the ability to target and silence nearly any gene of interest, specific siRNA can be constructed to target genes encoding proteins involved in DNA repair and the acquisition of multidrug resistance (6, 11). Naked siRNA cannot readily cross cellular membranes due to its polyanionic and macromolecular characteristics, and it is susceptible to degradation by endogenous enzymes (12). Therefore, considerable efforts have been made to develop safe and effective vehicles to facilitate the delivery of siRNA into cells (1315). Similarly, the methods by which chemotherapeutics are delivered also have a significant effect on the efficacy (16, 17). Recent research has begun to explore the feasibility of combining chemotherapeutics with siRNA using a variety of nanocarrier platforms (18, 19). One of the earliest efforts using this therapeutic paradigm involved cancer treatment by targeted minicells containing specific siRNA followed by drug-loaded minicells, which efficiently reversed drug resistance in drug-resistant tumors and produced enhanced therapeutic efficacy in inhibiting tumor growth (20). However, to exert optimal synergistic effects, both the drug and siRNA may need to be temporally colocalized in the tumor cells. As a result, nanocarrier platforms that are capable of simultaneously delivering siRNA and anticancer drugs to the same tumor cells are emerging as a promising nanomedicine approach for improved cancer therapy (21, 22).Nanoparticles (NPs) self-assembled from biodegradable PLGA-PEG block copolymers represent a promising class of potential delivery vehicles due to several unique properties: PLGA-PEG copolymers (i) are biocompatible and biodegradable and used in many U.S. Food and Drug Administration-approved products, (ii) are capable of encapsulating small- and macromolecular payloads with a wide range of physiochemical properties, and (iii) can be designed for controlled release through a combination of polymer degradation and drug diffusion (23). Recently, a docetaxel-containing formulation termed BIND-014 (BIND Biosciences), which has been selected from an NP library composed of poly(d,l-lactide), PLGA, and PEG, is currently in phase I clinical trials (24). Another NP system based on PLGA-PEG has been developed by Kolishetti et al. (25) for codelivery of cisplatin and docetaxel, two drugs with different characteristics and metabolic targets, to prostate cancer cells. However, there remains a pressing need to engineer nanocarriers that are capable of delivering combination therapeutics involving siRNA because systemic delivery of siRNA still remains challenging. Herein, we describe an integrated nanodelivery system capable of simultaneously delivering cisplatin prodrug and siRNAs against REV1 and REV3L to enhance chemosensitivity of tumors. PLGA-PEG was formulated with a cationic lipid-like molecule designated as G0-C14 into NPs that comprise three components: an aqueous inner core, a cationic and hydrophobic layer composed of PLGA and G0-C14, and a hydrophilic PEG corona (Fig. 1A). The G0-C14 compound is synthesized with cationic head groups that can efficiently bind siRNA via electrostatic interactions and flexible hydrophobic tails for self-assembly with PLGA-PEG to form Pt(IV)-prodrug encapsulating NPs (Fig. 1A). In this study, we applied a Pt(IV)-prodrug approach previously used in our laboratory to deliver cisplatin (26). In this approach, a unique Pt(IV) precursor compound, c,c,t [Pt(NH3)2Cl2(O2C(CH2)8CH3)2] (compound 1; Fig. 1B), was developed to allow the release of cisplatin at a lethal dose upon intracellular reduction. The linear decanoyl chains in compound 1 also enable efficient encapsulation within the hydrophobic layer of NPs and controlled release without compromising either feature (26). We investigated the ability of these polymer/lipid hybrid NPs to down-regulate the expression of target genes as well as to induce diminished resistance and enhanced therapeutic profile both in vitro and in vivo. Using a human Lymph Node Carcinoma of the Prostate (LNCaP) xenograft mouse model of prostate cancer, we further demonstrated that these hybrid NPs containing Pt(IV)-prodrug and REV1/REV3L-specific siRNAs (siREV1, siREV3L) cooperatively suppress tumor growth through synergistic effects.Open in a separate windowFig. 1.(A) Chemical structure of PLGA-PEG/G0-C14 NPs. The particle consists of three components: (i) an outer PEG surface, (ii) a PLGA/G0-C14 layer that plays two roles: (a) acting as a polymer matrix loaded with nonpolar drugs and (b) protecting and promoting siRNA molecule retention inside the NP core and controlling drug release, and (iii) an aqueous inner core containing siRNA. (B) Chemical structure of the hydrophobic platinum(IV) compound 1 and the chemistry by which the active drug cisplatin is released after reduction in the cell. (C) Synthesis of G0-C14 through ring opening of 1,2-epoxytetradecane by ethylenediamine core-PAMAM generation 0 dendrimer. (D) Size distribution of the NPs containing both compound 1 and siRNA determined by dynamic light scattering. (E) Representative transmission EM image of the NPs. (Scale bar, 200 nm.)  相似文献   
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