708 research outputs found
Healthcare Utilization and Costs Among High-Need and Frail Mexican American Medicare Beneficiaries
Objectives To examine Medicare health care spending and health services utilization among high-need population segments in older Mexican Americans, and to examine the association of frailty on health care spending and utilization.
Methods Retrospective cohort study of the innovative linkage of Medicare data with the Hispanic Established Populations for the Epidemiologic Study of the Elderly (H-EPESE) were used. There were 863 participants, which contributed 1,629 person years of information. Frailty, cognition, and social risk factors were identified from the H-EPESE, and chronic conditions were identified from the Medicare file. The Cost and Use file was used to calculate four categories of Medicare spending on: hospital services, physician services, post-acute care services, and other services. Generalized estimating equations (GEE) with a log link gamma distribution and first order autoregressive, correlation matrix was used to estimate cost ratios (CR) of population segments, and GEE with a logit link binomial distribution was applied to estimate odds ratios (OR) of healthcare use.
Results Participants in the major complex chronic illness segment who were also pre-frail or frail had higher total costs and utilization compared to the healthy segment. The CR for total Medicare spending was 3.05 (95% CI, 2.48–3.75). Similarly, this group had higher odds of being classified in the high-cost category 5.86 (95% CI, 3.35–10.25), nursing home care utilization 11.32 (95% CI, 3.88–33.02), hospitalizations 4.12 (95% CI, 2.88–5.90) and emergency room admissions 4.24 (95% CI, 3.04–5.91).
Discussion Our findings highlight that frailty assessment is an important consideration when identifying high-need and high-cost patients
The Stable Association of Virion with the Triple-geneblockProtein 3-based Complex of Bamboo mosaic virus
The triple-gene-block protein 3 (TGBp3) of Bamboo mosaic virus (BaMV) is an integral endoplasmic reticulum (ER) membraneprotein which is assumed to form a membrane complex to deliver the virus intracellularly. However, the virus entity that isdelivered to plasmodesmata (PD) and its association with TGBp3-based complexes are not known. Results from chemicalextraction and partial proteolysis of TGBp3 in membrane vesicles revealed that TGBp3 has a right-side-out membranetopology; i.e., TGBp3 has its C-terminal tail exposed to the outer surface of ER. Analyses of the TGBp3-specificimmunoprecipitate of Sarkosyl-extracted TGBp3-based complex revealed that TGBp1, TGBp2, TGBp3, capsid protein (CP),replicase and viral RNA are potential constituents of virus movement complex. Substantial co-fractionation of TGBp2, TGBp3and CP, but not TGBp1, in the early eluted gel filtration fractions in which virions were detected after TGBp3-specificimmunoprecipitation suggested that the TGBp2- and TGBp3-based complex is able to stably associate with the virion. Thisnotion was confirmed by immunogold-labeling transmission electron microscopy (TEM) of the purified virions. In addition,mutational and confocal microscopy analyses revealed that TGBp3 plays a key role in virus cell-to-cell movement byenhancing the TGBp2- and TGBp3-dependent PD localization of TGBp1. Taken together, our results suggested that the cellto-cell movement of potexvirus requires stable association of the virion cargo with the TGBp2- and TGBp3-based membranecomplex and recruitment of TGBp1 to the PD by this complex
Association of Cancer Diagnosis With Disability Status among Older Survivors of Colorectal Cancer: a Population-Based Retrospective Cohort Study
BACKGROUND: Older cancer survivors likely experience physical function limitations due to cancer and its treatments, leading to disability and early mortality. Existing studies have focused on factors associated with surgical complications and mortality risk rather than factors associated with the development of poor disability status (DS), a proxy measure of poor performance status, in cancer survivors. We aimed to identify factors associated with the development of poor DS among older survivors of colorectal cancer (CRC) and compare poor DS rates to an age-sex-matched, non-cancer cohort.
METHODS: This retrospective cohort study utilized administrative data from the Texas Cancer Registry Medicare-linked database. The study cohort consisted of 13,229 survivors of CRC diagnosed between 2005 and 2013 and an age-sex-matched, non-cancer cohort of 13,225 beneficiaries. The primary outcome was poor DS, determined by Davidoff\u27s method, using predictors from 12 months of Medicare claims after cancer diagnosis. Multivariable Cox proportional hazards regression was used to identify risk factors associated with the development of poor DS.
RESULTS: Among the survivors of CRC, 97% were 65 years or older. After a 9-year follow-up, 54% of survivors of CRC developed poor DS. Significant factors associated with future poor DS included: age at diagnosis (hazard ratio [HR] = 3.50 for \u3e80 years old), female sex (HR = 1.50), race/ethnicity (HR = 1.34 for Hispanic and 1.21 for Black), stage at diagnosis (HR = 2.26 for distant metastasis), comorbidity index (HR = 2.18 for \u3e1), and radiation therapy (HR = 1.21). Having cancer (HR = 1.07) was significantly associated with developing poor DS in the pooled cohorts; age and race/ethnicity were also significant factors.
CONCLUSIONS: Our findings suggest that a CRC diagnosis is independently associated with a small increase in the risk of developing poor DS after accounting for other known factors. The study identified risk factors for developing poor DS in CRC survivors, including Hispanic and Black race/ethnicity, age, sex, histologic stage, and comorbidities. These findings underscore the importance of consistent physical function assessments, particularly among subsets of older survivors of CRC who are at higher risk of disability, to prevent developing poor DS
Dual Supramolecular Nanoparticle Vectors Enable CRISPR/Cas9-Mediated Knockin of Retinoschisin 1 Gene-A Potential Nonviral Therapeutic Solution for X-Linked Juvenile Retinoschisis.
The homology-independent targeted integration (HITI) strategy enables effective CRISPR/Cas9-mediated knockin of therapeutic genes in nondividing cells in vivo, promising general therapeutic solutions for treating genetic diseases like X-linked juvenile retinoschisis. Herein, supramolecular nanoparticle (SMNP) vectors are used for codelivery of two DNA plasmids-CRISPR-Cas9 genome-editing system and a therapeutic gene, Retinoschisin 1 (RS1)-enabling clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (CRISPR/Cas9) knockin of the RS1 gene with HITI. Through small-scale combinatorial screenings, two SMNP vectors, with Cas9 and single guide RNA (sgRNA)-plasmid in one and Donor-RS1 and green fluorescent protein (GFP)-plasmid in the other, with optimal delivery performances are identified. These SMNP vectors are then employed for CRISPR/Cas9 knockin of RS1/GFP genes into the mouse Rosa26 safe-harbor site in vitro and in vivo. The in vivo study involves intravitreally injecting the two SMNP vectors into the mouse eyes, followed by repeated ocular imaging by fundus camera and optical coherence tomography, and pathological and molecular analyses of the harvested retina tissues. Mice ocular organs retain their anatomical integrity, a single-copy 3.0-kb RS1/GFP gene is precisely integrated into the Rosa26 site in the retinas, and the integrated RS1/GFP gene is expressed in the retinas, demonstrating CRISPR/Cas9 knockin of RS1/GFP gene
Testing the theory of immune selection in cancers that break the rules of transplantation
Modification of cancer cells likely to reduce their immunogenicity, including loss or down-regulation of MHC molecules, is now well documented and has become the main support for the concept of immune surveillance. The evidence that these modifications, in fact, result from selection by the immune system is less clear, since the possibility that they may result from reorganized metabolism associated with proliferation or from cell de-differentiation remains. Here, we (a) survey old and new transplantation experiments that test the possibility of selection and (b) survey how transmissible tumours of dogs and Tasmanian devils provide naturally evolved tests of immune surveillance
Blockade of Hsp90 by 17AAG antagonizes MDMX and synergizes with Nutlin to induce p53-mediated apoptosis in solid tumors
Strategies to induce p53 activation in wtp53-retaining tumors carry high potential in cancer therapy. Nutlin, a potent highly selective MDM2 inhibitor, induces non-genotoxic p53 activation. Although Nutlin shows promise in promoting cell death in hematopoietic malignancies, a major roadblock is that most solid cancers do not undergo apoptosis but merely reversible growth arrest. p53 inhibition by unopposed MDMX is one major cause for apoptosis resistance to Nutlin. The Hsp90 chaperone is ubiquitously activated in cancer cells and supports oncogenic survival pathways, many of which antagonize p53. The Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin (17AAG) is known to induce p53-dependent apoptosis. We show here that in multiple difficult-to-kill solid tumor cells 17AAG modulates several critical components that synergize with Nutlin-activated p53 signaling to convert Nutlin's transient cytostatic response into a cytotoxic killing response in vitro and in xenografts. Combined with Nutlin, 17AAG destabilizes MDMX, reduces MDM2, induces PUMA and inhibits oncogenic survival pathways, such as PI3K/AKT, which counteract p53 signaling at multiple levels. Mechanistically, 17AAG interferes with the repressive MDMX–p53 axis by inducing robust MDMX degradation, thereby markedly increasing p53 transcription compared with Nutlin alone. To our knowledge Nutlin+17AAG represents the first effective pharmacologic knockdown of MDMX. Our study identifies 17AAG as a promising synthetic lethal partner for a more efficient Nutlin-based therapy
Bone mass in schizophrenia and normal populations across different decades of life
<p>Abstract</p> <p>Background</p> <p>Chronic schizophrenic patients have been reported as having higher osteoporosis prevalence. Survey the bone mass among schizophrenic patients and compare with that of the local community population and reported data of the same country to figure out the distribution of bone mass among schizophrenic patients.</p> <p>Methods</p> <p>965 schizophrenic patients aged 20 years and over in Yuli Veterans Hospital and 405 members aged 20 and over of the community living in the same town as the institute received bone mass examination by a heel qualitative ultrasound (QUS) device. Bone mass distribution was stratified to analyzed and compared with community population.</p> <p>Results</p> <p>Schizophrenic patients have lower bone mass while they are young. But aging effect on bone mass cannot be seen. Accelerated bone mass loss during menopausal transition was not observed in the female schizophrenic patients as in the subjects of the community female population.</p> <p>Conclusion</p> <p>Schizophrenic patients have lower bone mass than community population since they are young. Further study to investigate the pathophysiological process is necessary to delay or avoid the lower bone mass in schizophrenia patients.</p
Stressing the Ubiquitin-Proteasome System without 20S Proteolytic Inhibition Selectively Kills Cervical Cancer Cells
Cervical cancer cells exhibit an increased requirement for ubiquitin-dependent protein degradation associated with an elevated metabolic turnover rate, and for specific signaling pathways, notably HPV E6-targeted degradation of p53 and PDZ proteins. Natural compounds with antioxidant properties including flavonoids and triterpenoids hold promise as anticancer agents by interfering with ubiquitin-dependent protein degradation. An increasing body of evidence indicates that their α-β unsaturated carbonyl system is the molecular determinant for inhibition of ubiquitin-mediated protein degradation up-stream of the catalytic sites of the 20S proteasome. Herein we report the identification and characterization of a new class of chalcone-based, potent and cell permeable chemical inhibitors of ubiquitin-dependent protein degradation, and a lead compound RAMB1. RAMB1 inhibits ubiquitin-dependent protein degradation without compromising the catalytic activities of the 20S proteasome, a mechanism distinct from that of Bortezomib. Treatment of cervical cancer cells with RAMB1 triggers unfolded protein responses, including aggresome formation and Hsp90 stabilization, and increases p53 steady state levels. RAMB1 treatment results in activation of lysosomal-dependent degradation pathways as a mechanism to compensate for increasing levels of poly-ubiquitin enriched toxic aggregates. Importantly, RAMB1 synergistically triggers cell death of cervical cancer cells when combined with the lysosome inhibitor Chloroquine
RavN is a member of a previously unrecognized group of Legionella pneumophila E3 ubiquitin ligases
The eukaryotic ubiquitylation machinery catalyzes the covalent attachment of the small protein modifier ubiquitin to cellular target proteins in order to alter their fate. Microbial pathogens exploit this post-translational modification process by encoding molecular mimics of E3 ubiquitin ligases, eukaryotic enzymes that catalyze the final step in the ubiquitylation cascade. Here, we show that the Legionella pneumophila effector protein RavN belongs to a growing class of bacterial proteins that mimic host cell E3 ligases to exploit the ubiquitylation pathway. The E3 ligase activity of RavN was located within its N-terminal region and was dependent upon interaction with a defined subset of E2 ubiquitin-conjugating enzymes. The crystal structure of the N-terminal region of RavN revealed a U-box-like motif that was only remotely similar to other U-box domains, indicating that RavN is an E3 ligase relic that has undergone significant evolutionary alteration. Substitution of residues within the predicted E2 binding interface rendered RavN inactive, indicating that, despite significant structural changes, the mode of E2 recognition has remained conserved. Using hidden Markov model-based secondary structure analyses, we identified and experimentally validated four additional L. pneumophila effectors that were not previously recognized to possess E3 ligase activity, including Lpg2452/SdcB, a new paralog of SidC. Our study provides strong evidence that L. pneumophila is dedicating a considerable fraction of its effector arsenal to the manipulation of the host ubiquitylation pathway.Funding: This work was funded by the Intramural Research Program of the National Institutes of Health (to MPM)(Project Number: 1ZIAHD008893-07) and by the Spanish Ministry of Economy and Competitiveness Grant (to AH)(BFU2014-59759-R) and the Severo Ochoa Excellence Accreditation (to AH)(SEV-2016-0644). This study made use of the Diamond Light Source beamline I04 (Oxfordshire, UK) and ALBA synchrotron beamline BL13-XALOC, funded in part by the Horizon 2020 programme of the European Union, iNEXT (H2020 Grant # 653706). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
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