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11.
Objectives. We investigated whether nonelderly US adults (aged 18–64 years) in food-insecure households are more likely to report cost-related medication underuse than the food-secure, and whether the relationship between food insecurity and cost-related medication underuse differs by gender, chronic disease, and health insurance status.Methods. We analyzed data from the 2011 and 2012 National Health Interview Survey (n = 67 539). We examined the relationship between food insecurity and cost-related medication underuse with the χ2 test and multivariate logistic regression with interaction terms.Results. Bivariate and multivariate analyses showed a dose–response relationship between food insecurity and cost-related medication underuse, with an increasing likelihood of cost-related medication underuse with increasing severity of food insecurity (P < .001). This association was conditional on health insurance status, but not substantially different by gender or chronic disease status. Being female, low-income, having no or partial health insurance, chronic conditions, functional limitations, or severe mental illness were positively associated with cost-related medication underuse.Conclusions. Using food insecurity as a risk factor to assess cost-related medication underuse could help increase identification of individuals who may need assistance purchasing medications and improve health for those in food-insecure households.Food insecurity refers to “limited or uncertain availability of nutritionally adequate and safe foods or limited or uncertain ability to acquire acceptable foods in socially acceptable ways.”1(p6) Food insecurity is associated with poor health status and risk factors such as obesity, metabolic conditions, and chronic diseases, potentially attributable to intake of poor-quality diets, which increase the risk for obesity and cardiometabolic diseases.2–5 Studies of diabetic patients living in food-insecure households have shown poor outcomes such as poor glycemic control and increased physician use.6,7 Moreover, there is evidence that people living in food-insecure households are more likely to have poor mental health outcomes,8,9 use alcohol,10 and smoke cigarettes11—factors also associated with poor health status.Recent research suggests that people living in food-insecure households may adjust their behaviors in ways that are potentially detrimental to their health. Ivers and Cullen suggest that the vulnerability of food insecurity puts individuals at risk for engaging in coping strategies (e.g., withdrawal of children from school, theft, and risky sexual behaviors), particularly among women who tend to be children’s primary caregivers.12 One set of behaviors that has received relatively little attention as a potential coping mechanism for food insecurity until recently is reducing, skipping, delaying, or using lower-cost medications to compensate for lack of household resources to purchase food. These behaviors have been described as cost-related medication underuse.13,14Studies have demonstrated the relationship between cost-related medication underuse and poor health outcomes,15–19 but, to our knowledge, only 1 study has examined the relationship between food insecurity and cost-related medication underuse in the United States in a nationally representative sample.13 This study, which was restricted to individuals with chronic diseases, found that those living in food-insecure households were more likely to report cost-related medication underuse. Similar findings have been demonstrated from smaller studies in different parts of the country among people with diabetes, people with HIV/AIDS, and patients presenting at emergency departments.20–24We extend the literature on behaviors individuals living in food-insecure households may adopt to save money for food by examining the relationships between food insecurity and cost-related medication underuse in a nationally representative sample of nonelderly adults living in the United States. The objective of this analysis was to determine whether nonelderly adults (aged 18–64 years) living in food-insecure households in the United States are more likely to report cost-related medication underuse. We also examined whether the relationship between food insecurity and cost-related medication underuse differs by gender, chronic disease status, and health insurance status.  相似文献   
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To study the impact of oncogenic K-Ras on T-cell leukemia/lymphoma development and progression, we made use of a conditional K-Ras(G12D) murine knockin model, in which oncogenic K-Ras is expressed from its endogenous promoter. Transplantation of whole bone marrow cells that express oncogenic K-Ras into wild-type recipient mice resulted in a highly penetrant, aggressive T-cell leukemia/lymphoma. The lymphoblasts were composed of a CD4/CD8 double-positive population that aberrantly expressed CD44. Thymi of primary donor mice showed reduced cellularity, and immunophenotypic analysis demonstrated a block in differentiation at the double-negative 1 stage. With progression of disease, approximately 50% of mice acquired Notch1 mutations within the PEST domain. Of note, primary lymphoblasts were hypersensitive to gamma-secretase inhibitor treatment, which is known to impair Notch signaling. This inhibition was Notch-specific as assessed by down-regulation of Notch1 target genes and intracellular cleaved Notch. We also observed that the oncogenic K-Ras-induced T-cell disease was responsive to rapamycin and inhibitors of the RAS/MAPK pathway. These data indicate that patients with T-cell leukemia with K-Ras mutations may benefit from therapies that target the NOTCH pathway alone or in combination with inhibition of the PI3K/AKT/MTOR and RAS/MAPK pathways.  相似文献   
15.
Kohlschütter–Tönz syndrome (KTS) is a rare autosomal recessive disorder characterized by amelogenesis imperfecta, psychomotor delay or regression and seizures starting early in childhood. KTS was established as a distinct clinical entity after the first report by Kohlschütter in 1974, and to date, only a total of 20 pedigrees have been reported. The genetic etiology of KTS remained elusive until recently when mutations in ROGDI were independently identified in three unrelated families and in five likely related Druze families. Herein, we report a clinical and genetic study of 10 KTS families. By using a combination of whole exome sequencing, linkage analysis, and Sanger sequencing, we identify novel homozygous or compound heterozygous ROGDI mutations in five families, all presenting with a typical KTS phenotype. The other families, mostly presenting with additional atypical features, were negative for ROGDI mutations, suggesting genetic heterogeneity of atypical forms of the disease.  相似文献   
16.
Objectives

This systematic review aims to evaluate current literature regarding available techniques for removal of osseointegrated implants in terms of explantation’s success, complications, and bone loss.

Material and methods

Two reviewers conducted a systematic literature search through electronic databases (PubMed and EMBASE), complimented by manual and grey literature searches. Successful explantation was defined as the primary outcome. Complications and availability of residual bone for immediate implantation were defined as secondary outcomes.

Results

Eighteen articles, comprising 372 implants and 241 patients, were included. Five techniques were identified: reverse torque, trephines, burs, piezosurgery, and laser-assisted explantation. Peri-implantitis was the most common reason for explantation, followed by crestal bone loss, fracture, and malpositioning. The reverse torque was the most frequently reported technique (284 implants) with 87.7% success rate. Burs were used for explantation of 49 implants with a 100% success rate, while trephines were utilized for removal of 35 implants with 94% success. Piezosurgery (11 implants) and Er.Cr:YSGG laser (1 implant) showed 100% success. One study reported perforation of the sinus floor following trephine explantation, while another reported fracture of 3 implants following reverse torque application. Further analysis was hindered by the quality of the available studies and their lack of data.

Conclusions

Reverse torque seems the most conservative, and in the authors’ opinion, should be the first choice for explantation despite its inferior success rate. Additional studies with randomized controlled designs and larger sample sizes are required.

Clinical relevance

Dental implants have become the leading choice to replace missing teeth with gradually increasing numbers of complications and failures. An effective, conservative, and economic explantation technique is necessary to allow a successive implant placement.

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Accurate chromosome segregation requires that replicated sister chromatids are held together until anaphase, when their "cohesion" is dissolved, and they are pulled to opposite spindle poles by microtubules. Establishment of new cohesion between sister chromatids in the next cell cycle is coincident with replication fork passage. Emerging evidence suggests that this temporal coupling is not just a coincident timing of independent events, but rather that the establishment of cohesion is likely to involve the active participation of replication-related activities. These include PCNA, a processivity clamp for some DNA polymerases, Trf4/Pol final sigma (formerly Trf4/Pol kappa), a novel and essential DNA polymerase, and a modified Replication Factor C clamp--loader complex. Here we describe recent advances in how cohesion establishment is linked to replication, highlight important unanswered questions in this new field, and describe a "polymerase switch" model for how cohesion establishment is coupled to replication fork progression. Building the bridges between newly synthesized sister chromatids appears to be a fundamental but previously unrecognized function of the eukaryotic replication machinery.  相似文献   
19.
Tubulointerstitial fibrosis is common with ageing and strongly prognostic for ESRD but is poorly captured by eGFR or urine albumin to creatinine ratio (ACR). Higher urine levels of procollagen type III N-terminal propeptide (PIIINP) mark the severity of tubulointerstitial fibrosis in biopsy studies, but the association of urine PIIINP with CKD progression is unknown. Among community-living persons aged ≥65 years, we measured PIIINP in spot urine specimens from the 1996 to 1997 Cardiovascular Health Study visit among individuals with CKD progression (30% decline in eGFR over 9 years, n=192) or incident ESRD (n=54) during follow-up, and in 958 randomly selected participants. We evaluated associations of urine PIIINP with CKD progression and incident ESRD. Associations of urine PIIINP with cardiovascular disease, heart failure, and death were evaluated as secondary end points. At baseline, mean age (±SD) was 78±5 years, mean eGFR was 63±18 ml/min per 1.73 m2, and median urine PIIINP was 2.6 (interquartile range, 1.4–4.2) μg/L. In a case-control study (192 participants, 231 controls), each doubling of urine PIIINP associated with 22% higher odds of CKD progression (adjusted odds ratio, 1.22; 95% confidence interval, 1.00 to 1.49). Higher urine PIIINP level was also associated with incident ESRD, but results were not significant in fully adjusted models. In a prospective study among the 958 randomly selected participants, higher urine PIIINP was significantly associated with death, but not with incident cardiovascular disease or heart failure. These data suggest higher urine PIIINP levels associate with CKD progression independently of eGFR and ACR in older individuals.  相似文献   
20.
Gain-of-function mutations that activate the innate immune system can cause systemic autoinflammatory diseases associated with increased IL-1β production. This cytokine is activated identically to IL-18 by an intracellular protein complex known as the inflammasome; however, IL-18 has not yet been specifically implicated in the pathogenesis of hereditary autoinflammatory disorders. We have now identified an autoinflammatory disease in mice driven by IL-18, but not IL-1β, resulting from an inactivating mutation of the actin-depolymerizing cofactor Wdr1. This perturbation of actin polymerization leads to systemic autoinflammation that is reduced when IL-18 is deleted but not when IL-1 signaling is removed. Remarkably, inflammasome activation in mature macrophages is unaltered, but IL-18 production from monocytes is greatly exaggerated, and depletion of monocytes in vivo prevents the disease. Small-molecule inhibition of actin polymerization can remove potential danger signals from the system and prevents monocyte IL-18 production. Finally, we show that the inflammasome sensor of actin dynamics in this system requires caspase-1, apoptosis-associated speck-like protein containing a caspase recruitment domain, and the innate immune receptor pyrin. Previously, perturbation of actin polymerization by pathogens was shown to activate the pyrin inflammasome, so our data now extend this guard hypothesis to host-regulated actin-dependent processes and autoinflammatory disease.Autoinflammatory syndromes are caused by dysregulation of the innate immune system, frequently affecting the inflammasome or other pathogen recognition pathways and leading to the overproduction of active IL-1β and IL-18 (Masters et al., 2009). To date, there are at least 12 known genetic causes of autoinflammatory disease, including familial Mediterranean fever (FMF), hyper-IgD syndrome, and cryopyrin-associated periodic syndrome. Therapeutic options for these diseases include nonsteroidal antiinflammatory drugs, corticosteroids, colchicine (for FMF), anti-TNF, and direct blockade of IL-1, which can be highly efficacious (Masters et al., 2009; Caso et al., 2013). IL-18 and IL-1β are produced in many cells, including monocytes and macrophages (Okamura et al., 1995; Ushio et al., 1996). IL-18 and IL-1β are produced as precursors and do not have a signal peptide to facilitate their secretion; instead, they are activated and released extracellularly as mature proteins after cleavage by caspase-1 (Li et al., 1995; Ghayur et al., 1997; Gu et al., 1997). Despite these similarities, there is no known hereditary autoinflammatory disease where the pathology is caused exclusively by IL-18.The inflammasome is an intracellular molecular platform that forms in response to pathogen- or danger-associated molecular patterns (DAMPs), leading to recruitment and activation of caspase-1 (Martinon et al., 2002; Schroder and Tschopp, 2010). A growing number of inflammasomes have been reported, each nucleated by a different innate immune receptor, such as NLRP1 (Martinon et al., 2000; Boyden and Dietrich, 2006), NLRP3 (Agostini et al., 2004), NLRC4 (Franchi et al., 2006), pyrin (Chae et al., 2011), and AIM2 (Hornung et al., 2009). Apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) is a key adaptor used by most of these innate immune receptors to interact with and recruit caspase-1 (Srinivasula et al., 2002). Activating mutations in NLRP3 result in increased IL-1β and IL-18 production, which can be prevented in mice by deleting caspase-1 or ASC. Furthermore, deleting either the IL-18R or the IL-1R can both independently protect mice from this NLRP3-mediated autoinflammatory disease (Brydges et al., 2013). For the FMF protein, pyrin, activating mutations induce ASC-dependent but NLRP3-independent IL-1β activation and cause severe autoinflammation in mice (Chae et al., 2011). Interestingly, pyrin interacts with ASC, microtubules, and actin filaments (Mansfield et al., 2001; Richards et al., 2001; Waite et al., 2009), and it has recently been shown that modification of RhoGTPases by bacterial toxins can trigger the pyrin inflammasome, perhaps via modulation of actin dynamics (Xu et al., 2014). This raises the fascinating prospect of a link between perturbations in the actin cytoskeleton and autoinflammatory disease.Wdr1 is required for disassembly of actin filaments in conjunction with the actin-depolymerizing factor/cofilin family of proteins. Mice homozygous for a hypomorphic allele of Wdr1 (Wdr1rd/rd) exhibit spontaneous autoinflammatory disease and thrombocytopenia (Kile et al., 2007). Both defects have been suggested to result from a disruption in actin dynamics. Thrombocytopenia results from defects in megakaryocytes, a cell type that is entirely dependent on a functional cytoskeleton to shed platelets (Patel et al., 2005). Wdr1 mutant mice also exhibit neutrophilia; however, the critical inflammatory mediators and cell types important for the development of inflammation in this genetic condition are unclear (Kile et al., 2007). Intriguingly, Wdr1 was found to be secreted after caspase-1 activation (Keller et al., 2008).We examined the role of key inflammatory mediators that drive autoinflammation in Wdr1rd/rd mice and demonstrated that this disease is IL-18 dependent, but IL-1 independent. As expected, this IL-18 is produced by the inflammasome; however, it is not produced from neutrophils or macrophages, but instead only from monocytes. Finally, we found that the autoinflammatory disease was mediated by pyrin, providing evidence that this innate immune receptor recognizes alterations in the actin polymerization pathway.  相似文献   
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