Causal Structure Learning with Conditional and Unique Information Groups-Decomposition Inequalities.

The causal structure of a system imposes constraints on the joint probability distribution of variables that can be generated by the system. Archetypal constraints consist of conditional independencies between variables. However, particularly in the presence of hidden variables, many causal structures are compatible with the same set of independencies inferred from the marginal distributions of observed variables. Additional constraints allow further testing for the compatibility of data with specific causal structures. An existing family of causally informative inequalities compares the information about a set of target variables contained in a collection of variables, with a sum of the information contained in different groups defined as subsets of that collection. While procedures to identify the form of these groups-decomposition inequalities have been previously derived, we substantially enlarge the applicability of the framework. We derive groups-decomposition inequalities subject to weaker independence conditions, with weaker requirements in the configuration of the groups, and additionally allowing for conditioning sets. Furthermore, we show how constraints with higher inferential power may be derived with collections that include hidden variables, and then converted into testable constraints using data processing inequalities. For this purpose, we apply the standard data processing inequality of conditional mutual information and derive an analogous property for a measure of conditional unique information recently introduced to separate redundant, synergistic, and unique contributions to the information that a set of variables has about a target.

Retrospective assessment of antimicrobial stewardship initiative in outpatient use of ertapenem for uncomplicated extended spectrum beta lactamase Enterobacteriaceae urinary tract infections.

BACKGROUND: Urinary tract infections (UTI) are often over-diagnosed and over-treated, which can induce and select for resistant pathogens. After observing wide-spread outpatient use of ertapenem, a broad-spectrum antibiotic, a structured antimicrobial stewardship initiative (ASI) to improve appropriate antimicrobial prescribing was undertaken. ASI objectives were to achieve a goal of reducing ertapenem utilization for extended spectrum beta lactamase Enterobacteriaceae (ESBL-EB) UTI by 10% and evaluate the clinical outcomes associated with the ASI. METHODS: A pre-to-post cohort study was conducted at a single-center integrated healthcare system between November 1, 2014 and February 26, 2017. An intensive, 90-day, pharmacist-driven, structured ASI was implemented between November 1, 2015 and January 29, 2016. Female patients aged ≥18 years who were treated for an uncomplicated, ESBL-EB urinary tract infection (UTI) were included. Primary outcome was clinical resolution defined as cure, persistence, relapse and recurrence. Secondary outcome measured was monthly ertapenem use expressed as number of days of therapy (DOT)/1000 adjusted patient days (APD). Segmented regression analysis for interrupted time series was performed to estimate ASI intervention effect. RESULTS: A total of 184 patients were included in the study. Ertapenem utilization decreased from 0.0145 DOT/1000 APD in Nov. 2014 to 0.0078 DOT/1000 APD Feb. 2017(p < 0.01). The mean ertapenem DOT declined 19% overall from the pre vs. post intervention periods (32 vs 26, p < 0.01). Frequency of recurrent UTIs between treatments did not significantly differ and no adverse effects were reported in patients treated with aminoglycosides. CONCLUSIONS: A structured ASI for uncomplicated ESBL-EB UTI was associated with a clinically meaningful decrease in ertapenem utilization and once-daily, 5-day aminoglycoside treatment was well-tolerated.

Identification of tumorigenic cells and therapeutic targets in pancreatic neuroendocrine tumors.

Pancreatic neuroendocrine tumors (PanNETs) are a type of pancreatic cancer with limited therapeutic options. Consequently, most patients with advanced disease die from tumor progression. Current evidence indicates that a subset of cancer cells is responsible for tumor development, metastasis, and recurrence, and targeting these tumor-initiating cells is necessary to eradicate tumors. However, tumor-initiating cells and the biological processes that promote pathogenesis remain largely uncharacterized in PanNETs. Here we profile primary and metastatic tumors from an index patient and demonstrate that MET proto-oncogene activation is important for tumor growth in PanNET xenograft models. We identify a highly tumorigenic cell population within several independent surgically acquired PanNETs characterized by increased cell-surface protein CD90 expression and aldehyde dehydrogenase A1 (ALDHA1) activity, and provide in vitro and in vivo evidence for their stem-like properties. We performed proteomic profiling of 332 antigens in two cell lines and four primary tumors, and showed that CD47, a cell-surface protein that acts as a "don't eat me" signal co-opted by cancers to evade innate immune surveillance, is ubiquitously expressed. Moreover, CD47 coexpresses with MET and is enriched in CD90(hi)cells. Furthermore, blocking CD47 signaling promotes engulfment of tumor cells by macrophages in vitro and inhibits xenograft tumor growth, prevents metastases, and prolongs survival in vivo.

Patterns of Care and Treatment Outcomes for Outpatient Daptomycin-Containing Regimens in Osteomyelitis.

BACKGROUND: Use of daptomycin at doses ≥ 6 mg/kg for treatment of osteomyelitis is increasing in clinical practice; unfortunately, limited data are available to guide optimal dosing and duration. The objective of this study was to assess daptomycin dosing and duration regimens for osteomyelitis treatment. METHODS: This was a retrospective, multi-site, cohort study conducted in an integrated healthcare delivery system. Nonpregnant patients ≥ 18 years of age with osteomyelitis diagnosed between November 1, 2003 and June 30, 2011, ≥ 2 weeks outpatient daptomycin therapy, and ≥ 1 month of follow-up were included. Daptomycin doses < 6 mg/kg and ≥ 6 mg/kg at durations of < 6 weeks and ≥ 6 weeks were examined with univariate and multivariate analyses to assess treatment success and all-cause mortality. RESULTS: A total of 247 patients were included, with 39 (15.8%), 37 (15.0%), 107 (43.3%), and 64 (25.9%) receiving < 6 mg/kg and ≥ 6 weeks, < 6 mg/kg and < 6 weeks, ≥ 6 mg/kg and ≥ 6 weeks, and ≥ 6 mg/kg and < 6 weeks of daptomycin therapy, respectively. Patients had a mean age of 58 years and had received prior vancomycin therapy (65.6%). Patients receiving < 6 weeks of therapy were less likely to experience treatment success compared with ≥ 6 weeks (41.5% vs 25.3%, adjusted odds ratio = 0.55; 95% confidence interval = 0.31-0.98) independent of duration. There were no differences across groups in mortality after adjustment. CONCLUSION: In a diverse clinical population, daptomycin for treatment of osteomyelitis of 6 weeks or longer duration was associated with success independent of dose. This finding supports longer treatment with daptomycin as a first-line agent in antimicrobial stewardship initiatives.

Association of Childhood Trauma Exposure with Inflammatory Biomarkers Among Midlife Women.

Background: Childhood abuse has been associated with poor health outcomes in adulthood. However, the physiologic pathways by which abuse is linked to health are not fully elucidated. Inflammation plays a significant role in the pathophysiology of multiple chronic diseases. We tested whether childhood trauma exposure was related to increased systemic inflammation in midlife women. Materials and Methods: Participants were 304 nonsmoking perimenopausal and postmenopausal women aged 40 to 60 years and free of cardiovascular disease. They completed questionnaires assessing psychosocial and behavioral factors, including childhood trauma, anthropometric measures, wrist actigraphy sleep measurements, and a fasting blood draw for inflammatory markers high-sensitivity C-reactive protein (hsCRP) and interleukin-6 (IL-6). Associations between childhood trauma and inflammatory markers were tested in linear regression models controlling for age, race/ethnicity, education, body mass index, anti-inflammatory medication use, and alcohol consumption. Other covariates considered included sleep continuity and depressive symptoms. Results: A total of 44.8% of the sample experienced at least one type of childhood abuse/neglect. Women with a history of emotional abuse had higher IL-6 levels than women without this history in multivariate models (ß = 0.077, standard error = 0.032, p = 0.017). Results were not accounted for by covariates and persisted additionally controlling for depressive symptoms and sleep. Childhood abuse/neglect was not related to hsCRP. Conclusions: Childhood emotional abuse was associated with higher levels of IL-6 in midlife women. Assessing childhood trauma exposure along with inflammatory markers may be important for the development of prevention strategies at midlife to prevent chronic diseases later in life.

Polypharmacy as a risk factor for adverse drug reactions in geriatric nursing home residents.

OBJECTIVE: Polypharmacy is a well-known risk factor for adverse drug reactions (ADRs). The objective of this study was to determine the relationship between the use of > or = 9 different scheduled medications and the occurrence of ADRs in geriatric nursing home residents. METHODS: This was a retrospective cohort study conducted in a 1200-bed, county-owned and -operated, longterm care skilled nursing facility Participants were 335 subjects aged > or = 65 years who were present at the facility during the index month of October 1998. Hospice, respite care, and rehabilitation patients were excluded. Use of > or = 9 different scheduled medications was defined a priori as routinely administered medications, excluding as-needed agents, topical agents, 1-time administration, and vaccinations. ADRs were identified by voluntary reporting and by chart review during a 12-month period. ADRs were assessed individually by 2 clinical pharmacists applying the Naranjo ADR probability scale. RESULTS: A total of 207 ADRs were identified. The cohort receiving > or = 9 scheduled medications (n = 43) experienced 53 ADRs, compared with 154 ADRs in the control group receiving <9 medications (n = 292). The demographic distribution was similar in both cohorts, with white as the dominant ethnicity; 45% were white in the control group and 51% were white in the cohort group receiving > or = 9 scheduled medications. The sex distribution was also similar, with women outnumbering men in both cohorts: 60% and 81% were women in the control and cohort groups, respectively. The mean age was 72 years (range, 65-100 years). After the data were adjusted for the number of days each subject was at risk for experiencing an ADR, subjects using > or = 9 different scheduled medications were 2.33 times more likely than controls to experience an ADR (95% CI, 1.54-3.52; P < 0.001). CONCLUSION: A positive correlation between the use of >/=9 different scheduled medications and ADRs was found among these geriatric nursing home residents.