Non-synaptic dendritic spines in neocortex

A long-held assumption states that each dendritic spine in the cerebral cortex forms a synapse, although this issue has not been systematically investigated. We performed complete ultrastructural reconstructions of a large (n=144) population of identified spines in adult mouse neocortex finding that only 3.6% of the spines clearly lacked synapses. Nonsynaptic spines were small and had no clear head, resembling dendritic filopodia, and could represent a source of new synaptic connections in the adult cerebral cortex.     

Enhanced neural activation with blueberry supplementation in mild cognitive impairment

Objectives: Preclinical studies have shown that blueberry supplementation can improve cognitive performance and neural function in aged animals and have identified associations between anthocyanins and such benefits. Preliminary human trials also suggest cognitive improvement in older adults, although direct evidence of enhancement of brain function has not been demonstrated. In this study, we investigated the effect of blueberry supplementation on regional brain activation in older adults at risk for dementia.

Methods: In a randomized, double-blind, placebo-controlled trial we performed pre- and post-intervention functional magnetic resonance imaging during a working memory (WM) task to assess the effect of blueberry supplementation on blood oxygen level-dependent (BOLD) signal in older adults with mild cognitive impairment, a risk condition for dementia.

Results: Following daily supplementation for 16 weeks, blueberry-treated participants exhibited increased BOLD activation in the left pre-central gyrus, left middle frontal gyrus, and left inferior parietal lobe during WM load conditions (corrected P?Discussion: These data demonstrate, for the first time, enhanced neural response during WM challenge in blueberry-treated older adults with cognitive decline and are consistent with prior trials showing neurocognitive benefit with blueberry supplementation in this at-risk population.     

Health beliefs, disease severity, and patient adherence: a meta-analysis

BACKGROUND: A large body of empirical data exists on the prediction of patient adherence from subjective and objective assessments of health status and disease severity. This work can be summarized with meta-analysis. OBJECTIVES: Retrieval and summary analysis of r effect sizes and moderators of the relationship between patient adherence and patients': (1) beliefs in disease threat; (2) rated health status (by physician, self, or parent); and (3) objective disease severity. METHODS: Comprehensive search of published literature (1948-2005) yielding 116 articles, with 143 separate effect sizes. Calculation of robust, generalizable random effects model statistics, and detailed examination of study diversity with moderator analyses. RESULTS: Adherence is significantly positively correlated with patients' beliefs in the severity of the disease to be prevented or treated ("disease threat"). Better patient adherence is associated with objectively poorer health only for patients experiencing disease conditions lower in seriousness (according to the Seriousness of Illness Rating Scale). Among conditions higher in seriousness, worse adherence is associated with objectively poorer health. Similar patterns exist when health status is rated by patients themselves, and by parents in pediatric samples. CONCLUSIONS: Results suggest that the objective severity of patients' disease conditions, and their awareness of this severity, can predict their adherence. Patients who are most severely ill with serious diseases may be at greatest risk for nonadherence to treatment. Findings can contribute to greater provider awareness of the potential for patient nonadherence, and to better targeting of health messages and treatment advice by providers.     

In vitro PFOS exposure on immune endpoints in bottlenose dolphins (Tursiops truncatus) and mice

Previous studies in our lab have shown that perfluorooctane sulfonate (PFOS) modulates immune function in mice and correlates with many immune parameters in bottlenose dolphins (Tursiops truncatus). In this study, bottlenose dolphin peripheral blood leukocytes (PBLs) and adult female B6C3F1 mouse splenocytes were exposed to environmentally relevant PFOS concentrations (0–5 µg ml^–1) in vitro; and natural killer (NK) cell activity and lymphocyte proliferation (T and B cell) were assessed using the parallelogram approach for risk assessment. The objectives were: to corroborate results from the correlative studies in bottlenose dolphins with in vitro PFOS exposures; to evaluate the sensitivity of the mouse model as compared with bottlenose dolphins; and to assess risk using the parallelogram approach. In mouse cells, NK cell activity was decreased at in vitro doses of 0.01, 0.5, 0.1, 0.5 and 1 µg PFOS ml^–1 and increased at 5 µg ml^–1. Additionally, B cell proliferation was not altered, but T cell proliferation was decreased at all in vitro PFOS exposures. In dolphin cells, NK cell activity and T cell proliferation were not altered by in vitro PFOS exposure, but B cell proliferation exhibited a positive association in relation to PFOS dose. Overall, the data indicates that: the in vitro exposures of bottlenose dolphin PBLs exhibited results similar to reported correlative fields studies; that mice were generally more sensitive (for these selected endpoints) than were dolphins; and that the parallelogram approach could be used two‐thirds of the time to predict the effects in bottlenose dolphins. Copyright © 2013 John Wiley & Sons, Ltd.     

Interactions of clindamycin with antibacterial defenses of the lung

Clindamycin is speculated to have select advantages in the treatment of certain infections because biologically active antibiotic is internalized by macrophages and PMNs in vitro. By challenging pulmonary host defenses with various bacterial species as probes, we were able to evaluate clindamycin-phagocyte interaction in vivo. A murine model was developed using an implanted mini-osmotic pump to maintain constant clindamycin blood levels at 1/4 MIC (1 microgram/ml). Mice pretreated for 24 h with clindamycin killed a significantly greater percentage of intratracheally inoculated Bacteroides thetaiotaomicron in 4 h than did control animals (37 +/- 2% versus 7 +/- 5%). The enhancing effects of clindamycin on pulmonary defenses could not be duplicated by a 1-h preincubation of B. theta in 1/4 MIC of clindamycin before inoculation into untreated mice. Clindamycin blood levels of 1 microgram/ml did not alter the rate at which Pseudomonas aeruginosa (clindamycin-resistant) was killed by pulmonary defenses, suggesting that clindamycin did not cause nonspecific activation of phagocytic defenses. Both PMNs and alveolar macrophages lavaged from the lungs of clindamycin-treated mice contained bioassayable concentrated intracellular antibiotic. The presence of intracellular antibiotic was further supported by experiments in which the intrapulmonary killing of large numbers of Staphylococcus aureus (sensitive, but not resistant organisms) was significantly enhanced (89 +/- 5 versus 70 +/- 5%) by clindamycin pretreatment. In contrast, phagocytes lavaged from mice with constant 1/4 MIC (4 micrograms/ml) blood levels of penicillin G had no detectable intracellular antibiotic activity and did not augment the intrapulmonary killing of B. theta.(ABSTRACT TRUNCATED AT 250 WORDS)     

Acquired factor VII deficiency associated with aplastic anaemia: correction with bone marrow transplantation

We report a patient with severe aplastic anaemia found to have a prolonged prothrombin time due to acquired factor VII deficiency. No evidence for a factor VII inhibitor or inactivator was demonstrable. Laboratory studies identified deficiency both of factor VII activity and factor VII antigen. The factor VII deficiency persisted from clinical presentation until approximately 50 d after allogeneic marrow transplantation when restoration of factor VII activity and antigen was noted. The patient's serum could be depleted of factor VII activity by in vitro incubation with Protein A bound to Sepharose, suggesting the presence of an IgG or IgG containing complex able to bind factor VII, but not neutralize its procoagulant activity. A dual specificity solid phase immunoassay identified a factor VII binding immunoglobulin which was detectable throughout the course of factor VII deficiency. The concordant appearance of this factor VII reactive immunoglobulin and the factor VII deficiency suggested the pathologic role of this immunoglobulin in the aetiology of the factor VII deficiency. This factor VII binding immunoglobulin may have induced rapid plasma clearance of the factor VII molecule or, alternatively, may have modified factor VII synthesis. The immunosuppressive therapy and subsequent lymphohaematopoietic engraftment following allogeneic marrow transplant was accompanied by complete resolution of the factor VII deficiency.     

Undiagnosed Acute Viral Febrile Illnesses,Sierra Leone

Sierra Leone in West Africa is in a Lassa fever–hyperendemic region that also includes Guinea and Liberia. Each year, suspected Lassa fever cases result in submission of ≈500–700 samples to the Kenema Government Hospital Lassa Diagnostic Laboratory in eastern Sierra Leone. Generally only 30%–40% of samples tested are positive for Lassa virus (LASV) antigen and/or LASV-specific IgM; thus, 60%–70% of these patients have acute diseases of unknown origin. To investigate what other arthropod-borne and hemorrhagic fever viral diseases might cause serious illness in this region and mimic Lassa fever, we tested patient serum samples that were negative for malaria parasites and LASV. Using IgM-capture ELISAs, we evaluated samples for antibodies to arthropod-borne and other hemorrhagic fever viruses. Approximately 25% of LASV-negative patients had IgM to dengue, West Nile, yellow fever, Rift Valley fever, chikungunya, Ebola, and Marburg viruses but not to Crimean-Congo hemorrhagic fever virus.     

Support for Smoke-Free Multi-Unit Housing Policies among Racially and Ethnically Diverse,low-Income Seniors in South Florida

Previous studies have gauged support for implementing smoke-free multi-unit housing (MUH) policies in the United States, but none have specifically examined attitudes among racially and ethnically diverse elders living in low-income MUH. We surveyed a convenience sample of elders 62 years of age and older (n?=?807) across 24 low-income housing properties in Broward County, Florida in order to assess residents’ smoking behaviors, exposure to second-hand smoke, and support for smoke-free policies. The study sample was ethnically and racially diverse with Hispanics comprising more than 61 % of the population, and 22 % identifying as Black or other races. Although close to 22 % of the sample were former smokers, only 9 % of residents reported being current smokers. The majority of residents surveyed supported no-smoking policies: 75 % support no-smoking policies for individual units; 77 % supported no-smoking policies in common areas; and, 68 % supported no-smoking policies in outdoor areas. Over 29 % of residents surveyed reported being exposed to secondhand smoke entering their units from elsewhere in their building. Residents who reported having a home smoking rule were more than twice as likely to support an indoor policy compared to residents who allowed smoking anywhere in their home (OR?=?2.36; 95%CI 1.25–4.43; p?≤?0.01), and nonsmoking residents were nearly three times as likely to support an indoor policy compared to smokers (OR?=?2.89; 95%CI 1.44–5.79; p?≤?0.01). Support for an indoor policy was not modified by age, gender, ethnicity or race. . This study demonstrates that elders living in low-income MUH properties overwhelmingly supported the implementation of smoke-free policies.