Brain-Derived Neurotrophic Factor Knockdown Blocks the Angiogenic and Protective Effects of Angiotensin Modulation After Experimental Stroke

Angiotensin type 1 receptor blockers (ARBs) have been shown to be neuroprotective and neurorestorative in experimental stroke. The mechanisms proposed include anti-inflammatory, antiapoptotic effects, as well as stimulation of endogenous trophic factors leading to angiogenesis and neuroplasticity. We aimed to investigate the involvement of the neurotrophin, brain-derived neurotrophic factor (BDNF), in ARB-mediated functional recovery after stroke. To achieve this aim, Wistar rats received bilateral intracerebroventricular (ICV) injections of short hairpin RNA (shRNA) lentiviral particles or nontargeting control (NTC) vector, to knock down BDNF in both hemispheres. After 14 days, rats were subjected to 90-min middle cerebral artery occlusion (MCAO) and received the ARB, candesartan, 1 mg/kg, or saline IV at reperfusion (one dose), then followed for another 14 days using a battery of behavioral tests. BDNF protein expression was successfully reduced by about 70 % in both hemispheres at 14 days after bilateral shRNA lentiviral particle injection. The NTC group that received candesartan showed better functional outcome as well as increased vascular density and synaptogenesis as compared to saline treatment. BDNF knockdown abrogated the beneficial effects of candesartan on neurobehavioral outcome, vascular density, and synaptogenesis. In conclusion, BDNF is directly involved in candesartan-mediated functional recovery, angiogenesis, and synaptogenesis.

Outpatient thyroid surgery: Safety of an optimized protocol in more than 1,000 patients

OBJECTIVES

Outpatient thyroid surgery is becoming increasingly common. The aim of this study was to clarify the principles for safe outpatient thyroid surgery and review our outcomes with the use of a protocol for outpatient thyroidectomy in a large patient cohort.

STUDY DESIGN

A systematic analysis of a prospectively maintained database of outcomes of thyroidectomy in a tertiary endocrine surgery practice.

SETTING

Academic medical center.

SUBJECTS AND METHODS

A protocol for outpatient thyroidectomy was conceived and refined over 3 years. A prospective analysis of all thyroidectomies accomplished by a single surgeon who used this protocol from May 2006 to November 2013 was then undertaken. Patient demographics, operative and pathologic data, admission status, complications, and readmission rates were recorded.

RESULTS

A total of 1,311 thyroidectomy procedures were performed during the study period, of which 1,026 (78.3 %) were conducted on an outpatient basis. The readmission rate for outpatients was 0.9%, with only 1 readmission in the last 200 procedures. Inpatients (which included patients in the 23-hour "observation" category) were readmitted more often than outpatients (3.5% vs 0.9%, P < .01). Outpatient management increased steadily throughout the study period (from 59.7% to 92.3%, P < .01), despite a larger mean nodule size and a greater rate of malignancy over time. There were no changes in the complication rate across the study timeframe except for the incidence of temporary hypocalcemia, which decreased over time (P < .01).

CONCLUSION

Outpatient thyroid surgery is safe in appropriately selected patients using an optimized and systematic protocol.

Cardiac implantable electronic device infection in patients with end-stage renal disease

INTRODUCTION

Cardiac implantable electronic devices (CIED) are increasingly being used in end-stage renal disease (ESRD) patients. These patients have a high risk of device infection.

OBJECTIVES

To study the optimal management of device infections in patients with ESRD.

METHOD

We used the United States Renal Data System (USRDS) to assess the presence of a CIED and associated comorbidities, risk factors for infection, and mortality following device extraction or medical management in ESRD patients with CIED infection. Univariable, multivariable, and survival analyses were performed using USRDS data from 2005 to 2009.

RESULTS

Of 546,769 patients, 6.4% had CIED and 8.0% of those developed CIED infection. The major risk factors for device infection were black race, temporary dialysis catheter, and body mass index >25. Patients with artificial valves were excluded from the analysis. Only 28.4% of infected CIED were removed. CIED removal was more common in those with congestive heart failure. The median time to death following diagnosis of a CIED infection was 15.7 months versus 9.2 months for those treated via device extraction versus medical-only therapy (hazard ratio: 0.75; 95% confidence interval: 0.68-0.82).

CONCLUSION

Patients with ESRD and infected CIEDs have a poor prognosis. Rates of device extraction are low, but this strategy appears to be associated with modest improvement in survival.

Six-Year Experience With Endoscopic Thyroidectomy: Outcomes and Safety Profile

BACKGROUND

Though minimally invasive video-assisted thyroidectomy (MIVAT) offers many advantages over traditional thyroid surgery, its adoption in North America has been limited. This study analyzes the largest series of MIVAT in North America to explore its safety.

METHODS

A prospectively maintained database of all patients undergoing thyroid surgery by a single surgeon from 2003 to 2011 at an academic tertiary care medical center was evaluated. Demographic information, surgical and pathologic data, and postoperative outcomes were analyzed.

RESULTS

Beginning in 2005, a total of 260 MIVATs were performed during the study period. Outpatient surgery was accomplished in 234 MIVATs (90%). MIVAT patients were predominantly young (46.8±14.8 years vs 52.4±14.6 years for conventional thyroidectomy) and female (88.5% vs 75.5% for conventional thyroidectomy). There were no cases of permanent hypoparathyroidism or permanent recurrent laryngeal nerve dysfunction. Observed complications included transient recurrent laryngeal nerve dysfunction (n=10; 3.8%), cellulitis (n=1; 0.4%), and temporary hypocalcemia (n=6; 2.3%). The overall complication rate for MIVAT (6.5%) was lower than the overall complication rate in conventional thyroidectomy (18.5%, P<.0001).

CONCLUSION

MIVAT can be performed safely with a low complication profile in a high-volume practice. The safety of MIVAT represented by this experience supports broader adoption across surgical practices.

NELF knockout is associated with impaired pubertal development and subfertility

Puberty and reproduction require proper signaling of the hypothalamic-pituitary-gonadal axis controlled by gonadotropin-releasing hormone (GnRH) neurons, which arise in the olfactory placode region and migrate along olfactory axons to the hypothalamus. Factors adversely affecting GnRH neuron specification, migration, and function lead to delayed puberty and infertility. Nasal embryonic luteinizing hormone-releasing factor (NELF) is a predominantly nuclear protein. NELF mutations have been demonstrated in patients with hypogonadotropic hypogonadism, but biallelic mutations are rare and heterozygous NELF mutations typically co-exist with mutations in another gene. Our previous studies in immortalized GnRH neurons supported a role for NELF in GnRH neuron migration. To better understand the physiology of NELF, a homozygous Nelf knockout (KO) mouse model was generated. Our findings indicate that female Nelf KO mice have delayed vaginal opening but no delay in time to first estrus, decreased uterine weight, and reduced GnRH neuron number. In contrast, male mice were normal at puberty. Both sexes of mice had impaired fertility manifested as reduced mean litter size. These data support that NELF has important reproductive functions. The milder than expected phenotype of KO mice also recapitulates the human phenotype since heterozygous NELF mutations usually require an additional mutation in a second gene to result in hypogonadotropic hypogonadism.

Comparison of asthma prevalence among African American teenage youth attending public high schools in rural Georgia and urban Detroit

BACKGROUND

The high prevalence of asthma among urban African American (AA) populations has attracted research attention, whereas the prevalence among rural AA populations is poorly documented.

OBJECTIVE

We sought to compare the prevalence of asthma among AA youth in rural Georgia and urban Detroit, Michigan.

METHODS

The prevalence of asthma was compared in population-based samples of 7297 youth attending Detroit public high schools and in 2523 youth attending public high schools in rural Georgia. Current asthma was defined as a physician diagnosis and symptoms in the previous 12 months. Undiagnosed asthma was defined as multiple respiratory symptoms in the previous 12 months without a physician diagnosis.

RESULTS

In Detroit, 6994 (95.8%) youth were AA compared with 1514 (60.0%) in Georgia. Average population density in high school postal codes was 5628 people/mile(2) in Detroit and 45.1 people/mile(2) in Georgia. The percentages of poverty and of students qualifying for free or reduced lunches were similar in both areas. The prevalence of current diagnosed asthma among AA youth in Detroit and Georgia was similar: 15.0% (95% CI, 14.1-15.8) and 13.7% (95% CI, 12.0-17.1) (P = .22), respectively. The prevalence of undiagnosed asthma in AA youth was 8.0% in Detroit and 7.5% in Georgia (P = .56). Asthma symptoms were reported more frequently among those with diagnosed asthma in Detroit, whereas those with undiagnosed asthma in Georgia reported more symptoms.

CONCLUSIONS

Among AA youth living in similar socioeconomic circumstances, asthma prevalence is as high in rural Georgia as it is in urban Detroit, suggesting that urban residence is not an asthma risk factor.

Porphyromonas gingivalis evasion of autophagy and intracellular killing by human myeloid dendritic cells involves DC-SIGN-TLR2 crosstalk

Signaling via pattern recognition receptors (PRRs) expressed on professional antigen presenting cells, such as dendritic cells (DCs), is crucial to the fate of engulfed microbes. Among the many PRRs expressed by DCs are Toll-like receptors (TLRs) and C-type lectins such as DC-SIGN. DC-SIGN is targeted by several major human pathogens for immune-evasion, although its role in intracellular routing of pathogens to autophagosomes is poorly understood. Here we examined the role of DC-SIGN and TLRs in evasion of autophagy and survival of Porphyromonas gingivalis in human monocyte-derived DCs (MoDCs). We employed a panel of P. gingivalis isogenic fimbriae deficient strains with defined defects in Mfa-1 fimbriae, a DC-SIGN ligand, and FimA fimbriae, a TLR2 agonist. Our results show that DC-SIGN dependent uptake of Mfa1+P. gingivalis strains by MoDCs resulted in lower intracellular killing and higher intracellular content of P. gingivalis. Moreover, Mfa1+P. gingivalis was mostly contained within single membrane vesicles, where it survived intracellularly. Survival was decreased by activation of TLR2 and/or autophagy. Mfa1+P. gingivalis strain did not induce significant levels of Rab5, LC3-II, and LAMP1. In contrast, P. gingivalis uptake through a DC-SIGN independent manner was associated with early endosomal routing through Rab5, increased LC3-II and LAMP-1, as well as the formation of double membrane intracellular phagophores, a characteristic feature of autophagy. These results suggest that selective engagement of DC-SIGN by Mfa-1+P. gingivalis promotes evasion of antibacterial autophagy and lysosome fusion, resulting in intracellular persistence in myeloid DCs; however TLR2 activation can overcome autophagy evasion and pathogen persistence in DCs.

Among the most successful of human microbes are intracellular pathogens. By entering the intracellular milieu, these pathogens are protected from harsh environmental factors in the host, including the humoral and cellular immune responses. Porphyromonas gingivalis is an opportunistic pathogen that colonizes the oral mucosa and accesses the bloodstream and distant sites such as the blood vessel walls, brain, placenta and other organs. Still unclear is how P. gingivalis traverses from oral mucosa to these distant sites. Dendritic cells are highly migratory antigen presenting cells that “patrol” the blood, skin, mucosa and all the major organ systems. Capture of microbes by dendritic cells activates a tightly regulated series of events, including directed migration towards the secondary lymphoid organs, where processed antigens are ostensibly presented to T cells. Autophagy is now recognized as an integral component of microbial clearance, antigen processing and presentation by dendritic cells. We report here that P. gingivalis is able to subvert autophagic destruction within dendritic cells. This occurs through its glycoprotein fimbriae, called Mfa-1, which targets the C-type lectin DC-SIGN on dendritic cells. The other major fimbriae on P. gingivalis, FimA, targets TLR2, which promotes autophagic destruction of P. gingivalis. We conclude that DC-SIGN-TLR2 crosstalk determines the intracellular fate of this pathogen within dendritic cells, and may have profound implications for the treatment of many chronic diseases involving low-grade infections.

A 2 × 2 factorial design for the combination therapy of minocycline and remote ischemic perconditioning: efficacy in a preclinical trial in murine thromboembolic stroke model

Background

After the failure of so many drugs and therapies for acute ischemic stroke, innovative approaches are needed to develop new treatments. One promising strategy is to test combinations of agents in the pre-hospital setting prior to the administration of intravenous tissue plasminogen activator (IV-tPA) and/ or the use of mechanical reperfusion devices in the hospital.

Methods

We performed a 2 × 2 factorial design preclinical trial where we tested minocycline (MINO), remote ischemic perconditioning (RIPerC) and their combination treatment in a thromboembolic clot model of stroke in mice, without IV-tPA or later treated with IV-tPA at 4 hours post-stroke. Cerebral blood flow (CBF) was measured by laser speckle contrast imaging (LSCI), behavioral outcomes as neurological deficit score (NDS) and adhesive tape removal test, and infarct size measurement were performed at 48 hours post-stroke. Mice within the experimental sets were randomized for the different treatments, and all outcome measures were blinded.

Results

RIPerC significantly improved CBF as measured by LSCI in both with and without tPA treated mice (P < 0.001). MINO and RIPerC treatment were effective alone at reducing infarct size (p < 0.0001) and improving short-term functional outcomes (p < 0.001) in the tPA and non-tPA treated animals. The combination treatment of MINO and RIPerC significantly reduced the infarct size greater than either intervention alone (p < 0.05). There were trends in favor of improving functional outcomes after combination treatment of MINO and RIPerC; however combination treatment group was not significantly different than the individual treatments of MINO and RIPerC. There was no “statistical” interaction between minocycline and RIPerC treatments indicating that the effects of RIPerC and MINO were additive and not synergistic on the outcome measures.

Conclusion

In the future, combining these two safe and low cost interventions in the ambulance has the potential to “freeze” the penumbra and improve outcomes in stroke patients. This pre-clinical 2 × 2 design can be easily translated into a pre-hospital clinical trial.

Incision Planning in Thyroid Compartment Surgery: Getting it Perfect

OBJECTIVE

This study evaluated changes in thyroid compartment incision site locations with patient positioning to define a reliable method for placing the scar in the optimal vertical location.

METHODS

The optimal incision location was marked with the patient sitting upright before surgery. The distance from the sternal notch to this mark was measured with the patient in the upright, supine, and final surgical positions.

RESULTS

Complete data were available for 104 procedures. The mean distances from the sternal notch to the incision site were 4.8, 21.5, and 31.9 mm in the sitting, supine, and surgical positions, respectively. Each of these distances were significantly different from one another (P<.0001) and were independent of patient age, sex, body mass index (BMI), or height.

CONCLUSIONS

Cutaneous cervical landmarks migrate significantly during patient positioning. Marking the thyroid compartment incision site while the patient is in an upright position results in a more predictable final scar location.

Biomechanical changes from long-term freezer storage and cellular reduction of tracheal scaffoldings

OBJECTIVES/HYPOTHESIS

To determine structural biomechanical changes in tracheal scaffolds resulting from cellular reduction and storage at -80(o) C.

STUDY DESIGN

Laboratory-based study.

METHODS

Forty-four rabbit tracheal segments were separated into four treatment groups: untreated (group A, control), cellular-reduced (group B), storage at -80(o) C followed by cellular reduction (group C), and cellular-reduced followed by storage at -80(o) C (group D). Tracheal segments were subjected to uniaxial tension (n = 21) or compression (n = 23) using a universal testing machine to determine sutured tensile yield load and radial compressive strengths at 50% lumen occlusion. Mean differences among groups for tension and compression were compared by analysis of variance with post-hoc Tukey-Kramer test.

RESULTS

The untreated trachea (group A) demonstrated mean yield strength of 5.93 (± 1.65) N and compressive strength of 2.10 (± 0.51) N. Following treatment/storage, the tensile yield strength was not impaired (group B = 6.79 [± 1.58] N, C = 6.21 [± 1.40] N, D = 6.26 [± 1.18]; P > 0.10 each). Following cellular reduction, there was a significant reduction in compressive strength (group B = 0.44 N [± 0.13], P < 0.0001), but no further reduction due to storage (group C = 0.39 N [± 0.10]; P = 0.97 compared to group B).

CONCLUSION

The data suggest cellular reduction leads to loss of compressive strength. Freezing at -80°C (either before, or subsequent to cellular reduction) may be a viable storage method for tracheal grafts.

Repeated exposures to diisopropylfluorophosphate result in impairments of sustained attention and persistent alterations of inhibitory response control in rats

Organophosphate (OP)-based chemicals are used worldwide for many purposes and they have likely saved millions of people from starvation and disease. However, due to their toxicity they can also pose a significant environmental risk. While considerable research has focused on the acute symptoms and long-term consequences of overtly toxic exposures to OPs, less attention has been given to the subject of repeated exposures to levels that are not associated with acute symptoms (subthreshold exposures). There is clinical evidence indicating that this type of OP exposure can lead to prolonged deficits in cognition; however only a few studies have addressed this issue prospectively in animal models. In this study, repeated subthreshold exposures to the OP nerve agent diisopropylfluorophosphate (DFP) were evaluated in a 5-Choice Serial Reaction Time Task (5C-SRTT), an animal model of sustained attention. Adult rats were trained to stably perform the 5C-SRTT and then injected subcutaneously with vehicle or DFP of 0.5mg/kg every other day for 30days. Behavioral testing occurred daily during the DFP-exposure period and throughout a 45day (OP-free) washout period. Compared to vehicle-treated controls, DFP-treated rats exhibited deficits in accuracy, increases in omissions and timeout responses during the OP exposure period, while no significant effects on premature responses, perseverative responses, or response latencies were noted. While the increase in timeout responses remained detectible during washout, all other DFP-related alterations in 5C-SRTT performance abated. When the demands of the task were increased by the presentation of variable intertrial intervals, premature responses were also elevated in DFP-treated rats during the washout period. These results indicate that repeated exposures to subthreshold doses of DFP lead to reversible impairments in sustained attention as well as persistent impairments of inhibitory response control in rats.

Endoscopic thyroidectomy is safe in patients with a high body mass index

BACKGROUND

Obesity is associated with a number of medical comorbidities and is considered a risk factor for surgical complications. However, the impact of obesity on the safety of minimally invasive video-assisted thyroidectomy (MIVAT) has not been well defined. We sought to determine the relationship between obesity and the risk of complications in patients undergoing MIVAT.

METHOD

A prospectively maintained database of all thyroid surgeries performed from January 2006 through June 2012 was searched and all cases of MIVAT were identified. Patients were stratified into three body mass index (BMI) groups according to the National Institutes of Health classification for obesity: normal (BMI ≤ 24.9 kg/m(2)), overweight (BMI 25-29.9 kg/m(2)) and obese (BMI ≥ 30 kg/m(2)). The total number of complications was compared among the three groups, and MIVAT patients were also compared to a cohort of patients undergoing conventional thyroid surgery.

RESULTS

There were 233 MIVATs performed on 223 patients. The mean overall BMI for the study population was 25.4 kg/m(2). There were 123 procedures (52.8%) in the normal group, 76 procedures (32.6%) in the overweight group, and 34 procedures (14.6%) in the obese group. Complications included 1 case of cellulitis (0.4%), 6 cases of temporary hypocalcemia (2.6%), and 6 cases of transient vocal fold paresis (2.6%). No patients suffered permanent hypocalcemia or a permanent recurrent laryngeal nerve injury. There were 9 complications in the normal group (7.3%), 4 complications in the overweight group (5.3%), and no complications in the obese group. Due to the low number of complications in this series, the overweight and obese groups were combined into a high BMI group for further analysis. Statistical analysis using simple logistic regression models revealed that there was no significant difference in the number of complications in patients with a high BMI compared with patients with a normal BMI (odds ratio [OR] 0.48 [confidence interval (CI) 0.14-1.63], p=0.2). The MIVAT group had fewer overall complications than the conventional thyroidectomy group.

CONCLUSIONS

Overweight and obese patients undergoing MIVAT in this series were not at an increased risk for surgical complications. The MIVAT procedure may be considered safe in patients with a high BMI, who may derive particular benefit from a minimally invasive approach.

Defining the biomechanical properties of the rabbit trachea

OBJECTIVES/HYPOTHESIS

Surgical advancements rely heavily on validated animal models. The New Zealand White (NZW) rabbit is a widely used model for airway research, including regenerative medicine applications. Currently, the biomechanical properties of the normal rabbit trachea are not known. Our objective was to define these properties to assist in the standardization and understanding of future airway research using this model.

STUDY DESIGN

Laboratory-based study.

METHODS

Fresh tracheas from four adult NZW rabbits were dissected into 20 segments. To examine the biomechanical properties, segments were subjected to uniaxial tension (n = 9) and compression (n = 11) testing. Yield and maximum load (tension) and force at 50% displacement (compression) were recorded, and differences between segments were examined using analysis of covariance.

RESULTS

Normative data for native rabbit trachea show mean maximum load = 6.44 newtons (N), yield load = 5.93 N, and compressive strength = 2.10 N. In addition to establishing the baseline measurements, statistically significant differences in tensile measures based on location along the trachea and diameter were identified. Proximal segments had significantly higher maximum load (P = .0029) and yield load (P = .0062) than distal segments. Association between diameter and both maximum load (P = .0139) and yield load (P = .0082) was observed.

CONCLUSIONS

The adult NZW rabbit trachea is intrinsically less able to withstand tensile and compressive forces, compared to other airway models such as sheep or cadaveric human. Establishment of normative values will enable future research into changes in tracheal biomechanical properties during regenerative medicine manipulation and processing.

Factors influencing critical care nurses' adoption of the AACN practice alert on verification of feeding tube placement

BACKGROUND

Clinical practice guidelines are intended to bridge the research-practice gap, yet little is known about how critical care nurses adopt guidelines. Feeding tube verification practices remain variable and have led to patient harm and death.

OBJECTIVES

To examine factors influencing critical care nurses' adoption of the American Association of Critical-Care Nurses (AACN) practice alert on verification of feeding tube placement and its 4 recommended clinical practices.

METHODS

Critical care nurses were invited to participate in a national, online questionnaire, guided by Rogers' diffusion of innovation framework. Descriptive statistics and logistic regression were used for data analysis. Alpha level was set at 0.05.

RESULTS

Fifty-five percent of the 370 participating nurses were aware of the practice alert, and 45% had adopted it in practice. Only 29% of the adopters had also implemented all 4 clinical practices. Significant predictors of adoption included BSN or higher nursing education and guideline characteristics of observability and trialability. Predictors of implementation of the clinical practices included staff nurse/charge nurse role, academic medical center, research/web-based information sources, and perception of a policy. Policy was the only significant predictor of implementation of all 4 practices. Adoption of the practice alert was also a predictor for 2 of 4 clinical practices.

CONCLUSIONS

Personal and organizational factors influenced implementation of practices associated with an AACN practice alert. Although a research-practice gap exists, the practice alert was a significant source of information for 2 of the clinical practices.

Student perspectives on sexual health: implications for interprofessional education

Interprofessional collaboration requires that health professionals think holistically about presenting concerns, particularly for multimodal problems like sexual dysfunction. However, health professions students appear to receive relatively little sexual health education, and generally none is offered on an interprofessional basis. To assess current degree of interprofessional thinking in sexual health care, 472 health professions students in Georgia, United States, were presented with a sexual dysfunction vignette and asked to rate the relevance of, and their familiarity with, interventions offered by several professionals. They also were asked to identify the most likely cause of the sexual dysfunction. Students rated relevance and familiarity with interventions as highest for physicians and lowest for dentists, with higher ratings of nurses by nursing students. More advanced students reported greater familiarity with mental health, physician, and physical therapy interventions. Finally, nursing students were less likely to attribute the dysfunction to a physical cause. These findings indicate that students may prioritize biomedical approaches in their initial assessment and may need additional supports to consider the spectrum of biopsychosocial factors contributing to sexual functioning. To encourage interprofessional critical thinking and prepare students for interprofessional care, sexual health curricula may be improved with the inclusion of interprofessional training. Specific recommendations for curriculum development are offered.

Abstract T MP20: A Rapid Clot Lysis Assay to Predict Response to IV rt-PA in Stroke

Background: The cornerstone of acute stroke therapy is intravenous rt-PA, with the goal of rapid thrombolysis and restoration of blood flow. Unfortunately, less than half of patients treated have a favorable outcome. Since recanalization is closely correlated with the clinical response, endogenous resistance to rt-PA may inhibit thrombolysis and neurologic improvement. The primary objective of this research study was to evaluate whether an in vitro clot lysis assay and thrombolytic biomarkers could predict response to IV rt-PA in acute ischemic stroke patients

Methods: Ischemic stroke patients who received IV rt-PA were recruited from two sites (Augusta, GA and Udine, Italy). Blood samples were collected prior to rt-PA administration and a favorable clinical response to rt-PA was specified as an NIHSS score of two or less at 24 hours. The time required for 50% platelet-poor clot lysis (C50%) was measured by an in vitro turbidimetric assay. The endogenous major fibrinolytic inhibitors (tissue plasminogen inhibitor, PAI-1; and α2-antiplasmin, α2-AP), D-dimer, fibrinogen and pro-thrombin time (PT), were assessed and correlated with clinical outcome.

Results: We enrolled 54 rt-PA recipients (63±15 years; 72% male, and 85% white). The mean NIHSS was 11.2±5.1 at admission and 8.2±8.1 at 24 hours; 36% of patients had a favorable clinical response. There was a moderate reduction in C50% among patients with a favorable clinical outcome compared to those with an unfavorable outcome (669.5±46.3 vs. 704.7±91.6; p=0.075). There was no significant difference in PT (13.6±0.8 sec vs. 13.8±1.2 sec; p=0.444), PAI-1(28.2±34.1 pg/mL vs. 19.8±25.9 pg/mL; p=0.321), α2-AP (85.1±7.2 % vs. 88.8±10.1 %; p=0.153), D-dimer (269.5±232.2 ng/mL vs. 368.2±444.6 ng/mL; p=0.303) or fibrinogen (318.1±71.4 mg/dL vs. 343.0±173.1 mg/dL; p=0.465) levels between subjects with favorable and unfavorable response to rt-PA. Summary: Lack of response to IV rt-PA in stroke patients may reflect endogenous resistance to fibrinolysis reflected by prolonged clot lysis in vitro. The utility of clot lysis to predict rt-PA unresponsiveness should be tested in a larger clinical study.

Comparative analysis of sodium coupled vitamin C transporter 2 in human osteoarthritis grade 1 and grade 3 tissues

Background

Nutrient levels are known to influence the development of osteoarthritis (OA), presumably by modulating levels of matrix biosynthesis and degradation. These processes may be affected by ascorbic acid (AA), an antioxidant which acts as a cofactor for numerous biochemical reactions and is essential for post-translational modifications of collagen. In this study we examined the expression of SVCT2, the only known Sodium coupled vitamin C transporter isoform present in articular cartilage, in human articular cartilage explants derived from both normal and osteoarthritis articular cartilage.

Methods

OA1 and OA3 human articular cartilage was carefully dissected and macroscopically graded for degeneration via the Collins scale. The tissue samples were histologically examined by Hematoxylin and Eosin and Safranin O and Fast Green staining. SVCT2 expression analysis was performed at mRNA level by quantitative real time PCR and at a protein level by immunohistochemistry.

Results

Our quantitative real time PCR showed marked variation in the expression of SVCT2 in human osteoarthritic articular cartilage. SVCT2 expression was significantly down-regulated (p = 0.0001) in the Collins grade 3 (OA3) compared to Collins grade 1 (OA1) tissue. Furthermore, slides stained with fluorescent antibodies to SVCT2 demonstrated greatly reduced fluorescence for the SVCT2 transporter on the chondrocyte plasma membrane in the osteoarthritic tissue samples.

Conclusions

These findings demonstrate that the expression of SVCT2 transporter is significantly altered in human osteoarthritic tissues (OA3). The modulation of this transporter could therefore potentially influence the prevention, management and treatment of osteoarthritis.

Comparison of enrollment rates of African-American families into a school-based tobacco prevention trial using two recruitment strategies in urban and rural settings

PURPOSE

This study evaluated similarities and differences of enrollment rates using two different recruitment strategies for a tobacco control trial in rural and urban African-American (AA) elementary school families.

DESIGN

A comparative study, nested within a larger randomized controlled trial, was used to test the effectiveness of two recruitment approaches on enrollment rates in rural and urban AA families.

SETTING

The study was conducted in 14 Title 1 elementary schools in the southeastern United States: 7 rural and 7 urban.

SUBJECTS

There were 736 eligible AA families, and 332 (45%) completed informed consent and were enrolled into the study.

INTERVENTION

The Facilitate, Open and transparent communication, Shared benefits, Team and tailored, Educate bilaterally, and Relationships, realistic and rewards (FOSTER) approach guided the two recruitment strategies: (1) written informational packets provided to fourth graders to take home to parents; and (2) proactive, face-to-face family information sessions held at schools.

MEASURES

Enrollment rates were based on responsiveness to the two recruitment strategies and completion of the informed consent process.

ANALYSIS

Chi-square, Cochran-Mantel-Haenszel, and Breslow-Day tests were performed.

RESULTS

Higher enrollment rates occurred during the family session for both rural and urban families (100% rural, 93.6% urban; p = .0475) than informational packets alone (28.7% rural, 22% urban; p < .0001). Rural family enrollment rates were overall higher than urban rates regardless of recruitment strategy (52.0% rural vs. 39.6% urban; p = .0008).

CONCLUSION

The findings suggest the FOSTER approach, although effective in both rural and urban settings, was more successful in recruiting rural families.

Barriers and facilitators to implementing delirium rounds in a clinical trial across three diverse hospital settings

Delirium occurs in more than half of hospitalized older adults with dementia, substantially worsening outcomes. The use of multiple strategies and a local opinion leader, unit champion, has cumulative and lasting effects compared with single-strategy interventions. The purpose of this article is to describe the early barriers and facilitators to rounding with unit champions in a cluster randomized clinical trial in Year 2 of a 5-year trial (5R01NR011042-02). This is a mixed-method study nested within an ongoing multisite cluster-randomized, controlled clinical trial. Descriptive and comparative statistics were collected on N = 192 nursing rounds. Qualitative data were thematically analyzed. On average, rounds lasted 25.54 min (SD = 13.18) and were conducted with the unit champion 64% of the time. This is one of the first studies to systematically address quantitative and qualitative barriers and facilitators to nurse-led delirium rounds, demonstrating the gradual adoption of an intervention in diverse clinical settings.

Differential long-term effects of haloperidol and risperidone on the acquisition and performance of tasks of spatial working and short-term memory and sustained attention in rats

A common feature of the neuropsychiatric disorders for which antipsychotic drugs are prescribed is cognitive dysfunction, yet the effects of long-term antipsychotic treatment on cognition are largely unknown. In the current study, we evaluated the effects of long-term oral treatment with the first-generation antipsychotic haloperidol (1.0 and 2.0 mg/kg daily) and the second-generation antipsychotic risperidone (1.25 and 2.5 mg/kg daily) on the acquisition and performance of two radial-arm maze (RAM) tasks and a five-choice serial reaction-time task (5C-SRTT) in rats during days 15-60 and 84-320 days of treatment, respectively. In the RAM, neither antipsychotic significantly affected the acquisition or performance of a spatial win shift or a delayed non-match-to-position task. Conversely, in the rats administered 5C-SRTT, haloperidol was associated with profound deficits in performance, and the subjects were not able to progress through all stages of task acquisition. Depending on the dose, risperidone was associated with a greater number of trials to meet specific performance criteria during task acquisition compared with vehicle-treated controls; however, most subjects were eventually able to achieve all levels of task acquisition. Both haloperidol and risperidone also increased the number of perseverative and time-out responses during certain stages of task acquisition, and the response and reward latencies were slightly higher than controls during several stages of the study. These results in rats suggest that while long-term treatment with haloperidol or risperidone may not significantly affect spatial working or short-term memory, both antipsychotics can (depending on dose) impair sustained attention, decrease psychomotor speed, increase compulsive-type behaviors, and impair cognitive flexibility.

Delirium superimposed on dementia is associated with prolonged length of stay and poor outcomes in hospitalized older adults

BACKGROUND

Current literature does not identify the significance of underlying cognitive impairment and delirium in older adults during and 30 days following acute care hospitalization.

OBJECTIVE

Describe the incidence, risk factors, and outcomes associated with incident delirium superimposed on dementia.

DESIGN

A 24-month prospective cohort study.

SETTING

Community hospital.

PATIENTS

A total of 139 older adults (>65 years) with dementia.

METHODS

This prospective study followed patients daily during hospitalization and 1 month posthospital. Main measures included dementia (Modified Blessed Dementia Rating score, Informant Questionnaire on Cognitive Decline in the Elderly), daily mental status change, dementia stage/severity (Clinical Dementia Rating, Global Deterioration Scale), delirium (Confusion Assessment Method), and delirium severity (Delirium Rating Scale-Revised-98). All statistical analysis was performed using SAS 9.3, and significance was an α level of 0.05. Logistic regression, analysis of covariance, or linear regression was performed controlling for age, gender, and dementia stage.

RESULTS

The overall incidence of new delirium was 32% (44/139). Those with delirium had a 25% short-term mortality rate, increased length of stay, and poorer function at discharge. At 1 month follow-up, subjects with delirium had greater functional decline. Males were more likely to develop delirium, and for every 1 unit increase in dementia severity (Global Deterioration Scale), subjects were 1.5 times more likely to develop delirium.

CONCLUSIONS

Delirium prolongs hospitalization for persons with dementia. Thus, interventions to increase early detection of delirium have the potential to decrease the severity and duration of delirium and to prevent unnecessary suffering and costs from the complications of delirium and unnecessary readmissions to the hospital.

Measuring psychological flexibility in medical students and residents: a psychometric analysis

PURPOSE

Psychological flexibility involves mindful awareness of our thoughts and feelings without allowing them to prohibit acting consistently with our values and may have important implications for patient-centered clinical care. Although psychological flexibility appears quite relevant to the training and development of health care providers, prior research has not evaluated measures of psychological flexibility in medical learners. Therefore, we investigated the validity of our learners' responses to three measures related to psychological flexibility.

METHODS

Fourth-year medical students and residents (n=275) completed three measures of overlapping aspects of psychological flexibility: (1) Acceptance and Action Questionnaire-II (AAQ-II); (2) Cognitive Fusion Questionnaire (CFQ); and (3) Mindful Attention and Awareness Questionnaire (MAAS). We evaluated five aspects of construct validity: content, response process, internal structure, relationship with other variables, and consequences.

RESULTS

We found good internal consistency for responses on the AAQ (α=0.93), MAAS (α=0.92), and CFQ (α=0.95). Factor analyses demonstrated a reasonable fit to previously published factor structures. As expected, scores on all three measures were moderately correlated with one another and with a measure of life satisfaction (p<0.01).

CONCLUSION

Our findings provide preliminary evidence supporting validity of the psychological flexibility construct in a medical education sample. As psychological flexibility is a central concept underlying self-awareness, this work may have important implications for clinical training and practice.