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131.
ABSTRACT: BACKGROUND: Despite the availability of evidence-based psychotherapies for depression and anxiety, they are underused in non-mental health specialty settings such as primary care. Hybrid effectiveness-implementation designs have the potential to evaluate clinical and implementation outcomes of evidence-based psychotherapies to improve their translation into routine clinical care practices. METHODS: This protocol article discusses the study methodology and implementation strategies employed in an ongoing, hybrid, type 2 randomized controlled trial with two primary aims: (1) to determine whether a brief, manualized cognitive behavioral therapy administered by Veterans Affairs Primary Care Mental Health Integration program clinicians is effective in treating depression and anxiety in a sample of medically ill (chronic cardiopulmonary diseases) primary care patients and (2) to examine the acceptability, feasibility, and preliminary outcomes of a focused implementation strategy on improving adoption and fidelity of brief cognitive behavioral therapy at two Primary Care-Mental Health Integration clinics. The study uses a hybrid type 2 effectiveness/implementation design to simultaneously test clinical effectiveness and to collect pilot data on a multifaceted implementation strategy that includes an online training program, audit and feedback of session content, and internal and external facilitation. Additionally, the study engages the participation of an advisory council consisting of stakeholders from Primary Care-Mental Health Integration, as well as regional and national mental health leaders within the Veterans Administration. It targets recruitment of 320 participants randomized to brief cognitive behavioral therapy (n = 200) or usual care (n = 120). Both effectiveness and implementation outcomes are being assessed using mixed methods, including quantitative evaluation (e.g., intent-to-treat analyses across multiple time points) and qualitative methods (e.g., focus interviews and surveys from patients and providers). Patient-effectiveness outcomes include measures of depression, anxiety, and physical health functioning using blinded independent evaluators. Implementation outcomes include patient engagement and adherence and clinician brief cognitive behavioral therapy adoption and fidelity. CONCLUSIONS: Hybrid designs are needed to advance clinical effectiveness and implementation knowledge to improve healthcare practices. The current article describes the rationale and challenges associated with the use of a hybrid design for the study of brief cognitive behavioral therapy in primary care. Although trade-offs exist between scientific control and external validity, hybrid designs are part of an emerging approach that has the potential to rapidly advance both science and practice. Trial registration NCT01149772 at http://www.clinicaltrials.gov/ct2/show/NCT01149772.  相似文献   
132.
Cryptosporidiosis, caused by the protozoan parasite Cryptosporidium parvum, causes self-limited diarrhea in normal hosts but can cause life-threatening diarrhea for immunosuppressed patients. There is an urgent need for new drugs to treat this chronic disease. Cryptosporidium parvum infection is associated with intestinal structural and pathophysiologic changes, including villi blunting and glucose malabsorption. Substance P (SP), a neuropeptide and pain transmitter, is associated with the gastrointestinal tract and is elevated in humans and macaques after experimental C. parvum challenge. To examine the relevance of SP in the pathogenesis of cryptosporidiosis, and to determine if SP receptor antagonism can be employed for treatment of cryptosporidiosis in immunosuppressed hosts, we used an immunosuppressed murine model (dexamethasone-immunosuppressed mice) that is frequently utilized for examining chemotherapeutic potential of drugs. Quantitative ELISA was used to measure intestinal SP levels in immunosuppressed mice with, and without, C. parvum infection. Intestinal physiological alterations, as studied by the Ussing chamber technique, plus weight change, fecal oocyst shedding, and villi measurements, were compared in infected mice with, and without, SP receptor antagonist (aprepitant) treatment. Immunosuppressed mice infected with C. parvum demonstrated increased SP levels as well as physiological alterations (glucose malabsorption), weight loss, fecal oocyst shedding, and structural alterations (increased intestinal villi blunting) compared to uninfected mice. Each of these defects was significantly inhibited by aprepitant treatment. These studies demonstrate the potential of SP receptor antagonism for treatment of pathogenesis of cryptosporidiosis in immunosuppressed hosts.  相似文献   
133.
The HMGN proteins are a group of non-histone nuclear proteins that associate with the core nucleosome and alter the structure of the chromatin fiber. We investigated the distribution of the three best characterized HMGN family members, HMGN1, HMGN2 and HMGN3 during mouse eye development. HMGN1 protein is evenly distributed in all ocular structures of 10.5 days post-coitum (dpc) mouse embryos however, by 13.5dpc, relatively less HMGN1 is detected in the newly formed lens fiber cells compared to other cell types. In the adult, HMGN1 is detected throughout the retina and lens, although in the cornea, HMGN1 protein is predominately located in the epithelium. HMGN2 is also abundant in all ocular structures of mouse embryos, however, unlike HMGN1, intense immunolabeling is maintained in the lens fiber cells at 13.5dpc. In the adult eye, HMGN2 protein is still found in all lens nuclei while in the cornea, HMGN2 protein is mostly restricted to the epithelium. In contrast, the first detection of HMGN3 in the eye is in the presumptive corneal epithelium and lens fiber cells at 13.5dpc. In the lens, HMGN3 remained lens fiber cell preferred into adulthood. In the cornea, HMGN3 is transiently upregulated in the stroma and endothelium at birth while its expression is restricted to the corneal epithelium in adulthood. In the retina, HMGN3 upregulates around 2 weeks of age and is found at relatively high levels in the inner nuclear and ganglion cell layers of the adult retina. RT-PCR analysis determined that the predominant HMGN3 splice form found in ocular tissues is HMGN3b which lacks the chromatin unfolding domain although HMGN3a mRNA is also detected. These results demonstrate that the HMGN class of chromatin proteins has a dynamic expression pattern in the developing eye.  相似文献   
134.
Centralized banks for human embryonic stem cells: a worthwhile challenge   总被引:2,自引:0,他引:2  
Centralized banking of human embryonic stem (hES) cells is an endeavor that can benefit individual research efforts and enhance international collaboration but is complicated by the fact that the science is rapidly evolving in an environment of heterogeneous laws, guidelines, and ethical standards. Written from the vantage point of regulatory professionals, this article provides an overview of the benefits of and challenges facing hESC banking enterprises in general with a focus on a global centralized banking effort.  相似文献   
135.
A method is described for on-line enrichment/zone sharpening of a sample of negatively charged proteins (an analogous method for cationic proteins can be designed). The sample is applied on the top of a 5-mm thick layer of a neutral polyacrylamide gel which rests on another 5-mm thick, large-pore polyacrylamide gel which contains positively charged groups. The latter gel layer is attached to the neutral gel column, used for the electrophoretic separation of the proteins. When a voltage is applied the proteins start migrating and become electrostatically adsorbed at the top of the charged, large-pore gel layer (pH 5.4). With the upper electrode vessel filled with a buffer of a pH higher (pH 7.7) than that employed in the enrichment step and with a voltage between the electrodes, these enriched proteins are released (because the enrichment gel is non-charged at pH 7.7) with zone sharpening and migrate into the 5-cm long column (i.d. 5 mm) of a neutral, large-pore polyacrylamide gel for electrophoretic analysis. Upon the electrophoretic migration from the enrichment gel into the separation gel a second zone sharpening may occur, if the increase in pH from 5.4 to 7.7 in the separation gel is not close to momentary. By employing colored test proteins the efficiency of the enrichment step is visually illustrated by a picture. The principle of the concentration method described has been employed also in chromatographic experiments and can with appropriate modifications also be used in other electrophoretic methods, such as capillary electrophoresis.  相似文献   
136.
Ecologists have long sought to understand the relationships among species diversity, community productivity and invasion by non‐native species. Here, four long‐term observational datasets were analyzed using repeated measures statistics to determine how plant species richness and community resource capture (i.e. productivity) influenced invasion. Multiple factors influenced the results, including the metric used to quantify invasion, interannual variation and spatial scale. Native richness was positively correlated with non‐native richness, but was usually negatively correlated with non‐native abundance, and these patterns were stronger at the larger spatial scale. Logistic regressions indicated that the probability of invasion was reduced both within and following years with high productivity, except at the desert grassland site where high productivity was associated with increased invasion. Our analysis suggests that while non‐natives were most likely to establish in species rich communities, their success was diminished by high resource capture by the resident community.  相似文献   
137.
DNA from over 300 Bacillus thuringiensis, Bacillus cereus, and Bacillus anthracis isolates was analyzed by fluorescent amplified fragment length polymorphism (AFLP). B. thuringiensis and B. cereus isolates were from diverse sources and locations, including soil, clinical isolates and food products causing diarrheal and emetic outbreaks, and type strains from the American Type Culture Collection, and over 200 B. thuringiensis isolates representing 36 serovars or subspecies were from the U.S. Department of Agriculture collection. Twenty-four diverse B. anthracis isolates were also included. Phylogenetic analysis of AFLP data revealed extensive diversity within B. thuringiensis and B. cereus compared to the monomorphic nature of B. anthracis. All of the B. anthracis strains were more closely related to each other than to any other Bacillus isolate, while B. cereus and B. thuringiensis strains populated the entire tree. Ten distinct branches were defined, with many branches containing both B. cereus and B. thuringiensis isolates. A single branch contained all the B. anthracis isolates plus an unusual B. thuringiensis isolate that is pathogenic in mice. In contrast, B. thuringiensis subsp. kurstaki (ATCC 33679) and other isolates used to prepare insecticides mapped distal to the B. anthracis isolates. The interspersion of B. cereus and B. thuringiensis isolates within the phylogenetic tree suggests that phenotypic traits used to distinguish between these two species do not reflect the genomic content of the different isolates and that horizontal gene transfer plays an important role in establishing the phenotype of each of these microbes. B. thuringiensis isolates of a particular subspecies tended to cluster together.  相似文献   
138.
Objective: To describe the determinants, specifically age, body mass index, percentage of body fat, and physical activity (PA) level, associated with over‐ and underestimation of energy expenditure (EE) using PA records and the Stanford Seven‐Day Physical Activity Recall (7DR) compared with doubly labeled water (DLW). Research Methods and Procedures: We collected PA measures on 24 males eating a controlled diet designed to maintain body weight, and we determined EE from DLW and estimated EE from PA records and 7DR. Results: Absolute differences in the estimation of EE between DLW and PA assessment methods were greater for the 7DR (30.6 ± 9.9%) than PA records (7.9 ± 3.2%). In PA records, overestimation of EE was greater with older age and higher body fatness; EE was overestimated by 16.7% among men 50 years and older compared with only 5.3% among men <40 years of age. For percentage of body fat, EE was overestimated by 19.7% among men with a percentage of body fat ≥30% compared with only 5.6% among men with a percentage of body fat <25%. A trend for less overestimation of EE with higher levels of PA (measured by DLW/basal metabolic rate [BMR]) also was observed in the PA records. In the 7DR, the estimates of EE varied widely and no trends were observed by age, percentage of body fat, and PA levels. Discussion: Estimation of EE from the 7DR is considerably more variable than from PA records. Factors related to age and percentage of body fat influenced the accuracy of estimated EE in the PA record. Additional studies are needed to understand factors related to accurate reporting of PA behaviors, which are used to estimate EE in free‐living adults.  相似文献   
139.
Objective: The conventional ratio method (milliliters O2 per mass) typically is used to express Vo 2 peak. The goal of the current study was to compare Vo 2 peak of obese girls with normal‐weight girls by ratio and allometric scaling methods. Research Methods and Procedures: We compared Vo 2 peak by ratio and allometric methods in 46 obese and 47 normal‐weight girls. Indirect calorimetry was used to measure Vo 2 peak during either treadmill running or walking. Regression analysis was used to determine coefficients for mass and stature for each group with ANOVA used to compare data between groups. Results: The obese girls were taller and had higher values of body fatness (p ≤ 0.05). Absolute Vo 2 peak (liters per minute) was similar between groups ; however Vo 2 peak relative to mass was 50% lower (p ≤ 0.05) in the obese girls. When Vo 2 peak (milliliters per minute per kilogram) and mass were correlated, r = ?0.48 was found in the obese group. Allometric scaling of logarithmic transformed stature and mass reduced this to r = ?0.002, thus eliminating the bias associated with the ratio method. Adjusting Vo 2 peak allometrically scaled for mass, stature, and the combination of mass and stature reduced the difference between groups from 50% (ratio method) to 10% to 11% (p ≤ 0.05) with higher values found in the normal‐weight girls. Discussion: These results demonstrate the bias associated with the ratio method when comparing Vo 2 peak in obese girls with Vo 2 peak in normal‐weight girls. Allometric scaling eliminated the bias and thus may reflect a truer comparative response.  相似文献   
140.
We examined 154 Norwegian B. cereus and B. thuringiensis soil isolates (collected from five different locations), 8 B. cereus and 2 B. thuringiensis reference strains, and 2 Bacillus anthracis strains by using fluorescent amplified fragment length polymorphism (AFLP). We employed a novel fragment identification approach based on a hierarchical agglomerative clustering routine that identifies fragments in an automated fashion. No method is free of error, and we identified the major sources so that experiments can be designed to minimize its effect. Phylogenetic analysis of the fluorescent AFLP results reveals five genetic groups in these group 1 bacilli. The ATCC reference strains were restricted to two of the genetic groups, clearly not representative of the diversity in these bacteria. Both B. anthracis strains analyzed were closely related and affiliated with a B. cereus milk isolate (ATCC 4342) and a B. cereus human pathogenic strain (periodontitis). Across the entire study, pathogenic strains, including B. anthracis, were more closely related to one another than to the environmental isolates. Eight strains representing the five distinct phylogenetic clusters were further analyzed by comparison of their 16S rRNA gene sequences to confirm the phylogenetic status of these groups. This analysis was consistent with the AFLP analysis, although of much lower resolution. The innovation of automated genotype analysis by using a replicated and statistical approach to fragment identification will allow very large sample analyses in the future.  相似文献   
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