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Background: Health care-associated infections are a common cause of patient morbidity and mortality. We sought to describe the trends in these infections in acute care hospitals, using data from 3 national point-prevalence surveys., Methods: The Canadian Nosocomial Infection Surveillance Program (CNISP) conducted descriptive point-prevalence surveys to assess the burden of health care-associated infections on a single day in February of 2002, 2009 and 2017. Surveyed infections included urinary tract infection, pneumonia, Clostridioides difficile infection, infection at surgical sites and bloodstream infections. We compared the prevalence of infection across the survey years and considered the contribution of antimicrobial-resistant organisms as a cause of these infections., Results: We surveyed 28 of 33 (response rate 84.8%) CNISP hospitals (6747 patients) in 2002, 39 of 55 (response rate 71.0%) hospitals (8902 patients) in 2009 and 47 of 66 (response rate 71.2%) hospitals (9929 patients) in 2017. The prevalence of patients with at least 1 health care-associated infection increased from 9.9% in 2002 (95% confidence interval [CI] 8.4%-11.5%) to 11.3% in 2009 (95% CI 9.4%-13.5%), and then declined to 7.9% in 2017 (95% CI 6.8%-9.0%). In 2017, device-associated infections accounted for 35.6% of all health care-associated infections. Methicillin-resistant Staphylococcus aureus (MRSA) accounted for 3.9% of all organisms identified from 2002 to 2017; other antibiotic-resistant organisms were uncommon causes of infection for all survey years., Interpretation: In CNISP hospitals, there was a decline in the prevalence of health care-associated infection in 2017 compared with previous surveys. However, strategies to prevent infections associated with medical devices should be developed. Apart from MRSA, few infections were caused by antibiotic-resistant organisms., Competing Interests: Competing interests: None declared., (© 2019 Joule Inc. or its licensors.)

Mast cells are tissue-resident immune cells. Their overgrowth/overactivation results in a range of common distressing, sometimes life-threatening disorders, including asthma, psoriasis, anaphylaxis, and mastocytosis. Currently, drug discovery is hampered by use of cancer-derived mast cell lines or primary cells. Cell lines provide low numbers of mature mast cells and are not representative of in vivo mast cells. Mast cell generation from blood/bone marrow gives poor reproducibility, requiring 8-12 weeks of culture. Here we report a method for the rapid/robust production of mast cells from pluripotent stem cells (PSCs). An advantageous Gata2Venus reporter enriches mast cells and progenitors as they differentiate from PSCs. Highly proliferative mouse mast cells and progenitors emerge after 2 weeks. This method is applicable for rapid human mast cell generation, and could enable the production of sufficient numbers of physiologically relevant human mast cells from patient induced PSCs for the study of mast cell-associated disorders and drug discovery., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

The current study examined the neurochemical mechanisms and neuroanatomical changes underlying coexisting behavioral effects associated with chronic-stress-induced alterations in serotonin (5HT) neurons. Chronic unpredictable stress (CUS) to adult male rats produced depression-like changes with cognitive dysfunction and selective cell death in the interfascicular nucleus of the dorsal raphe (DRif), resulting in decreased 5HTergic innervation of medial prefrontal cortex (mPFC). Twenty-one days of CUS decreased basal plasma levels of corticosterone and produced a shorter latency to immobility and longer durations of immobility in the force-swim test that persisted for 1 month after CUS. Deficits in acquisition, recall, perseveration, and reversal learning were evident 1 month after CUS. MK801 treatment during CUS blocked the changes in the forced-swim test and deficits in memory recall. These behavioral changes were associated with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive soma and the eventual loss of 5HT neurons in the DRif and its projections to the mPFC as evidenced by fewer labeled cells in the DRif after retrograde tracer injections into the mPFC of stressed rats. Similar to the effects of MK801 on behavior, MK801 pretreatment during stress blocked the CUS-induced decreases in 5HT soma within the DRif and its projections to the mPFC. Finally, the depression-like behaviors were blocked by acute injection of the 5HT2A/C agonist (-)-2,5-dimethoxy-4-iodoamphetamine hydrochloride into the mPFC before forced-swim testing. These results identify a cause and mechanism of 5HTergic dysfunction of the mPFC and associated mood and cognitive behaviors. SIGNIFICANCE STATEMENT Chronic stress causes persistent mood and cognitive changes typically associated with dysregulated serotonin (5HT) transmission in the medial prefrontal cortex (mPFC), but the cause of this dysregulation is unknown. Prior studies have focused on 5HTergic terminals in this region, but this study shows that chronic stress causes NMDA-receptor-dependent and subregion-specific cell death of 5HT neurons in the dorsal raphe. The consequent decreased 5HT innervation of the mPFC was associated with mood and cognitive changes that persisted long after the termination of stress. These findings identify a mechanism of subregion-selective death of 5HT neurons in the dorsal raphe, a defined neuroanatomical pathway, and a behavioral phenotype that mirror stress-associated diseases such as major depressive disorder., Competing Interests: The authors declare no competing financial interests., (Copyright © 2017 the authors 0270-6474/17/376214-10$15.00/0.)

Objective: To investigate the effects of gait training with body weight support (BWS) on a treadmill versus overground in individuals with chronic stroke., Design: Randomized controlled trial., Setting: University research laboratory., Participants: Individuals (N=28) with chronic stroke (>6mo from the stroke event)., Interventions: Participants were randomly assigned to receive gait training with BWS on a treadmill (n=14) or overground (n=14) 3 times a week for 6 weeks., Main Outcome Measures: Gait speed measured using the 10-meter walk test, endurance measured using the 6-minute walk test, functional independence measured using the motor domain of the FIM, lower limb recovery measured using the lower extremity domain of the Fugl-Meyer assessment, step length, step length symmetry ratio, and single-limb support duration. Measurements were obtained at baseline, immediately after the training session, and 6 weeks after the training session., Results: At 1 week after the last training session, both groups improved in all outcome measures except paretic step length and step length symmetry ratio, which were improved only in the overground group (P=.01 and P=.01, respectively). At 6 weeks after the last training session, all improvements remained and the treadmill group also improved paretic step length (P<.001) but not step length symmetry ratio (P>.05)., Conclusions: Individuals with chronic stroke equally improve gait speed and other gait parameters after 18 sessions of BWS gait training on either a treadmill or overground. Only the overground group improved step length symmetry ratio, suggesting a role of integrating overground walking into BWS interventions poststroke., (Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

The purpose of this retrospective study was to examine the relationship between demographic and educational variables and student performance on an internal medicine (IM) clerkship in order to target areas for educational intervention and potential early remediation. This study examined data associated with third-year medical student performance (N = 505) during the IM clerkship at Baylor Scott & White, Temple/Texas A&M Health Science Center College of Medicine from 2005 to 2011. Multiple regression analysis (N = 341) showed that a model containing the following variables was significantly associated with scores on the National Board of Medical Examiners (NBME) subject exam, accounting for 46.5% of the variance: Objective Structured Clinical Exam (OSCE), Medical College Admissions Test (MCAT), US Medical Licensing Exam (USMLE) Step 1, second-year grade point average (GPA), and clinical evaluation. A model containing USMLE Step 1, clinical evaluation, and NBME was significantly associated with OSCE score, accounting for 30% of the variance. Additionally, a model containing age, MCAT score, undergraduate GPA, NBME subject exam score, and OSCE was significantly associated with clinical evaluation score, accounting for 22% of score variance. Age accounted for the most unique variance in clinical evaluation score. Gender and IM interest group were not significantly associated with any outcome variable. In conclusion, in contrast to previous studies in the field, we did not find a significant association between undergraduate GPA and NBME score. Our findings supply further evidence that the OSCE, typically believed to be a clinical performance exam, actually assesses a broader set of domains. Interest group membership did not confer any academic benefit to medical students in IM clerkships in our study.

Background: The use of infection control measures in the management of vancomycin-resistant enterococci (VRE) is hotly debated. A risk-managed approach to VRE control after the introduction of 2 horizontal infection prevention measures-an environmental cleaning (EC) and an antimicrobial stewardship (AMS) program-was assessed., Methods: Routine screening for VRE was discontinued 6 and 4 months after introduction of the EC and AMS programs, respectively. Only 4 units (intensive care, burns-trauma, solid organ transplant, and bone marrow transplant units) where patients were deemed to be at increased risk for VRE infection continued screening and contact precautions. Cost avoidance and value-added benefits were monitored by the hospital finance department. VRE monitoring on these high-risk units and facility-wide comprehensive bacteremia surveillance continued as per established protocols. Surveillance for methicillin-resistant Staphylococcus aureus (MRSA) and Clostridium difficile infection (CDI) remained unchanged., Results: VRE bacteremia rates did not increase with the change to the VRE risk-managed approach. The number of patients requiring VRE isolation in all areas of the hospital decreased from an average of 32 to 6 beds per day. Statistically significant reductions in CDI and MRSA rates were observed possibly related to the aggressive decluttering, equipment cleaning, and AMS program elements., Conclusion: A risk-managed approach to VRE can be implemented without adverse consequences and potentially with significant benefits to a facility., (Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)

Although it is generally accepted that cellular differentiation requires changes to transcriptional networks, dynamic regulation of promoters and enhancers at specific sets of genes has not been previously studied en masse. Exploiting the fact that active promoters and enhancers are transcribed, we simultaneously measured their activity in 19 human and 14 mouse time courses covering a wide range of cell types and biological stimuli. Enhancer RNAs, then messenger RNAs encoding transcription factors, dominated the earliest responses. Binding sites for key lineage transcription factors were simultaneously overrepresented in enhancers and promoters active in each cellular system. Our data support a highly generalizable model in which enhancer transcription is the earliest event in successive waves of transcriptional change during cellular differentiation or activation., (Copyright © 2015, American Association for the Advancement of Science.)

A bilateral advantage for diotically presented stimuli has been observed for cochlear implant (CI) users and is suggested to be dependent on symmetrical implant performance. Studies using CI simulations have not shown a true "bilateral" advantage, but a "better ear" effect and have demonstrated that performance decreases with increasing basalward shift in insertion depth. This study aimed to determine whether there is a bilateral advantage for CI simulations with interaurally matched insertions and the extent to which performance is affected by interaural insertion depth mismatch. Speech perception in noise and self-reported ease of listening were measured using matched bilateral, mismatched bilateral and unilateral CI simulations over four insertion depths for seventeen normal hearing listeners. Speech scores and ease of listening reduced with increasing basalward shift in (interaurally matched) insertion depth. A bilateral advantage for speech perception was only observed when the insertion depths were interaurally matched and deep. No advantage was observed for small to moderate interaural insertion-depth mismatches, consistent with a better ear effect. Finally, both measures were poorer than expected for a better ear effect for large mismatches, suggesting that misalignment of the electrode arrays may prevent a bilateral advantage and detrimentally affect perception of diotically presented speech.

Background: The Canadian Nosocomial Infection Surveillance Program (CNISP) has conducted surveillance for incident cases of methicillin-resistant Staphylococcus aureus (MRSA) in sentinel hospitals since 1995. In 2007, a reliability audit of the 2005 data was conducted., Methods: In 2005, 5,652 cases were submitted to the CNISP from 43 hospitals. A proportional sample of submitted forms (up to 25) from each site were randomly selected. Stratified random sampling was used to obtain the comparison data. The original data were compared with the reabstracted data for congruence on 7 preselected variables., Results: Reabstracted data were received from 30 out of 43 hospitals (70%), providing 443 of the 598 case forms requested (74%). Of these, 397 (90%) had matching case identification numbers. Overall, the percentage of discordant responses was 7.0%, ranging from 3.5% for sex and up to 23.7% for less well-defined variables (eg, where MRSA was acquired)., Conclusion: Our findings suggest that, in general, the 2005 MRSA data are reliable. However to improve reliability a data quality framework with quality assurance practices, including ongoing auditing should be integrated into the CNISP's surveillance programs. Providing training to data collectors and standard definitions with practical examples may help to improve data quality, especially for those variables that require clinical judgment., (Crown Copyright © 2012. Published by Mosby, Inc. All rights reserved.)

Purpose: Sarcopenia and increased fat infiltration in muscle may play a role in the functional impairment and high risk for diabetes in stroke. Our purpose was to compare muscle volume and muscle attenuation across 6 muscles of the paretic and nonparetic thigh and examine the relationships between intramuscular fat and insulin resistance and between muscle volume and strength in stroke patients., Methods: Stroke participants (70; 39 men, 31 women) aged 40 to 84 years, BMI = 16 to 45 kg/m(2) underwent multiple thigh CT scans, total body scan by DXA (dual-energy X-ray absorptiometry), peak oxygen intake (VO(2peak)) graded treadmill test, 6-minute walk, fasting blood draws, and isokinetic strength testing., Results: Muscle volume is 24% lower and subcutaneous fat volume is 5% higher in the paretic versus nonparetic thigh. Muscle attenuation (index of amount of fat infiltration in muscle) is 17% higher in the nonparetic midthigh than the paretic. The semitendinosis/semimembranosis, biceps femoris, sartorius, vastus (medialis/lateralis), and rectus femoris have lower (between 9% and 19%) muscle areas on the paretic than the nonparetic thigh. Muscle attenuation is 15% to 25% higher on the nonparetic than the paretic side for 5 of 6 muscles. The nonparetic midthigh muscle attenuation is negatively associated with insulin. Eccentric peak torque of the nonparetic leg and paretic leg are associated with the corresponding muscle volume., Conclusions: The skeletal muscle atrophy, increased fat around and within muscle, and ensuing muscular weakness observed in chronic stroke patients relates to diabetes risk and may impair functional mobility and independence.

Chronic recordings from ensembles of cortical neurons in primary motor and somatosensory areas in rhesus macaques provide accurate information about bipedal locomotion (Fitzsimmons NA, Lebedev MA, Peikon ID, Nicolelis MA. Front Integr Neurosci 3: 3, 2009). Here we show that the linear and angular kinematics of the ankle, knee, and hip joints during both normal and precision (attentive) human treadmill walking can be inferred from noninvasive scalp electroencephalography (EEG) with decoding accuracies comparable to those from neural decoders based on multiple single-unit activities (SUAs) recorded in nonhuman primates. Six healthy adults were recorded. Participants were asked to walk on a treadmill at their self-selected comfortable speed while receiving visual feedback of their lower limbs (i.e., precision walking), to repeatedly avoid stepping on a strip drawn on the treadmill belt. Angular and linear kinematics of the left and right hip, knee, and ankle joints and EEG were recorded, and neural decoders were designed and optimized with cross-validation procedures. Of note, the optimal set of electrodes of these decoders were also used to accurately infer gait trajectories in a normal walking task that did not require subjects to control and monitor their foot placement. Our results indicate a high involvement of a fronto-posterior cortical network in the control of both precision and normal walking and suggest that EEG signals can be used to study in real time the cortical dynamics of walking and to develop brain-machine interfaces aimed at restoring human gait function.

Background: As part of a comprehensive approach to decreasing Clostridium difficile in our health authority, an evaluation of the in-use performance of 2 brands of bedpan decontaminators (BPDs) in 2 acute care facilities was performed., Methods: A continuous quality improvement approach consisting of 5 BPD audits and 4 intervention phases was used over a 16-month evaluation period. Visible fecal soil on processed items was used as the progress indicator, and infection preventionists performed audits., Results: A total of 1,982 observations was recorded. Percent failures rates ranged from 7.6% to 33% dependent on the intervention phase. Polypropylene materials had fewer failures compared with stainless steel. The addition of rinse agent significantly improved results particularly in polypropylene items (1% failure rate). A number of human factors issues and equipment design features compromised the BPD's ability to function adequately., Conclusion: Users should thoroughly evaluate the in-use efficacy of BPDs and use a step-wise approach to identify and correct both human and equipment deficiencies. Forced function and compliance features for correct loading of machines, detergent and rinse agent dispensing, and ability to operate the machine only when detergent is present should be integral to the BPD design., (Copyright © 2011 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.)

Background: Coated coils for endovascular treatment of cerebral aneurysm were developed to reduce recurrence and retreatment rates, and have been in clinical use for 8-9 years without robust evidence to determine their efficacy. We assessed the efficacy and safety of hydrogel-coated coils., Methods: This randomised trial was undertaken in 24 centres in seven countries. Patients aged 18-75 years with a previously untreated ruptured or unruptured cerebral aneurysm of 2-25 mm in maximum diameter were randomly allocated (1:1) to aneurysm coiling with either hydrogel-coated coils or standard bare platinum coils (control). Randomisation was done with a computer-generated sequence, stratified by aneurysm size, shape, and dome-to-neck ratio; intention to use assist device; and by region. Participants and those assessing outcomes were masked to allocation. Analysis was by modified intention to treat (excluding missing data). Primary outcome was a composite of angiographic and clinical outcomes at 18-month follow-up. We also did prespecified subgroup analyses of characteristics likely to be relevant to angiographic outcome. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN30531382., Findings: 249 patients were allocated to the hydrogel coil group and 250 to the control group. In 44 of 467 patients for whom an 18-month composite primary outcome was unavailable, 6-month angiographic results were used. 70 (28%) patients in the hydrogel group and 90 (36%) control patients had an adverse composite primary outcome, giving an absolute reduction in the proportion of adverse composite primary outcomes with hydrogel of 7·0% (95% CI -1·6 to 15·5), odds ratio (OR) 0·73 (0·49-1·1, p=0·13). In a prespecified subgroup analysis in recently ruptured aneurysms, there were more adverse composite primary outcomes in the control group than in the hydrogel group-OR 2·08 (1·24-3·46, p=0·014). There were 8·6% fewer major angiographic recurrences in patients allocated to hydrogel coils-OR 0·7 (0·4-1·0, p=0·049). There were five cases of unexplained hydrocephalus in not-recently-ruptured aneurysms in the hydrogel coil group and one case in the control group., Interpretation: Whether use of hydrogel coils reduces late aneurysm rupture or improves long-term clinical outcome is not clear, but our results indicate that their use lowers major recurrence., Funding: MicroVention Inc., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Before 2009, the feasibility of applying brain-machine interfaces (BMIs) to control prosthetic devices had been limited to upper limb prosthetics such as the DARPA modular prosthetic limb. Until recently, it was believed that the control of bipedal locomotion involved central pattern generators with little supraspinal control. Analysis of cortical dynamics with electroencephalography (EEG) was also prevented by the lack of analysis tools to deal with excessive signal artifacts associated with walking. Recently, Nicolelis and colleagues paved the way for the decoding of locomotion showing that chronic recordings from ensembles of cortical neurons in primary motor (M1) and primary somatosensory (S1) cortices can be used to decode bipedal kinematics in rhesus monkeys. However, neural decoding of bipedal locomotion in humans has not yet been demonstrated. This study uses non-invasive EEG signals to decode human walking in six nondisabled adults. Participants were asked to walk on a treadmill at their self-selected comfortable speed while receiving visual feedback of their lower limbs, to repeatedly avoid stepping on a strip drawn on the treadmill belt. Angular kinematics of the left and right hip, knee and ankle joints and EEG were recorded concurrently. Our results support the possibility of decoding human bipedal locomotion with EEG. The average of the correlation values (r) between predicted and recorded kinematics for the six subjects was 0.7 (± 0.12) for the right leg and 0.66 (± 0.11) for the left leg. The average signal-to-noise ratio (SNR) values for the predicted parameters were 3.36 (± 1.89) dB for the right leg and 2.79 (± 1.33) dB for the left leg. These results show the feasibility of developing non-invasive neural interfaces for volitional control of devices aimed at restoring human gait function.

Background: Before the emergence of the pandemic (H1N1) 2009 virus, estimates of the stockpiles of facial protective equipment (FPE) and the impact that information had on personnel during a pandemic varied., Objective: To describe the impact of H1N1 on FPE use and hospital employee absenteeism. Setting. One tertiary care hospital and 2 community hospitals in the Vancouver Coastal Health (VCH) region, Vancouver, Canada. Patients. All persons with influenza-like illness admitted to the 3 VCH facilities during the period from June 28 through December 19, 2009., Methods: Data on patients and on FPE use were recorded prospectively. Data on salaried employee absenteeism were recorded during the period from August 1 through December 19, 2009., Results: During the study period, 865 patients with influenza-like illness were admitted to the 3 VCH facilities. Of these patients, 149 (17.2%) had laboratory-confirmed H1N1 influenza infection. The mean duration of hospital stay for these patients was 8.9 days, and the mean duration of intensive care unit stay was 9.2 days. A total of 134,281 masks and 173,145 N95 respirators (hereafter referred to as respirators) were used during the 24-week epidemic, double the weekly use of both items, compared with the previous influenza season. A ratio of 3 masks to 4 respirators was observed. Use of disposable eyewear doubled. Absenteeism mirrored the community epidemiologic curve, with a 260% increase in sick calls at the epidemic peak, compared with the nadir., Conclusion: Overall, FPE use more than doubled, compared with the previous influenza season, with respirator use exceeding literature estimates. A significant proportion of FPE resources were used while managing suspected cases. Planners should prepare for at least a doubling in mask and respirator use, and a 3.6-fold increase in staff sick calls.

In a companion manuscript we reported reduced electroencephalographic (EEG) activation at traditional sensorimotor areas in knee movements with high levels of task difficulty modulated by varying visual and proprioceptive sensory demands. Given that reduced cortical activity with more complex tasks is counter-intuitive, we suggested that high order cognitive-motor areas may show increased EEG activation to compensate for the observed decrease in sensorimotor regions. To test this hypothesis, we evaluated theta band activation at anterior frontal regions in a secondary analysis of our previous data. Unlike activation at sensorimotor areas, anterior frontal responses increased with each level of task difficulty as modulated by precision of visual targeting and/or proprioceptive demands from adding masses to the leg. Activity was increased as both unimodal visual and proprioceptive requirements became more demanding, but showed greater sensitivity to visual over proprioceptive processing requirements. Each level of bimodal task demands showed increasing activation, which was consistently greater when modulated through visual demands. These results are consistent with our hypothesis of increased contribution of anterior frontal regions for motor control in lower extremity movements with increasing sensory demands and further support different mechanisms for internally and externally guided movement.

We used electroencephalography to see how the brain deals with altered sensory processing demands in lower extremity movements. In unimodal conditions, sensory processing demands were altered with subjects performing movement to a small or large visual target, or with a small or large weight to modify proprioception. In bimodal conditions, both weight and targets needed to be met. We assessed activity over primary sensorimotor, premotor and parietal areas before and during knee movements. In unimodal conditions, the primary sensorimotor area showed the least sensitivity to the maximally increased sensory demand in both vision and proprioception, while the premotor region was most sensitive to proprioceptive demands, and the parietal region showed greatest sensitivity to visual demands. In bimodal conditions, intermediate levels of sensory processing demand maximally increased activation at premotor and parietal regions. However, when visual and proprioceptive demands were both maximal, activation decreased and was similar to that seen with the lowest level of sensory processing demand. As behavior was consistent across conditions while activation at these regions decreased, we suggest that additional brain areas, possibly high order cognitive and attentional regions, may be required to augment the function of the traditional sensorimotor network in lower extremity movements with increasingly difficult sensory processing demands.

Cognitive behaviour therapy (CBT) for young people with obsessive compulsive disorder (OCD) has become the treatment of first choice. However, the literature is largely based on studies emphasising exposure and response prevention. In this study, we report on a randomised controlled trial of CBT for young people carried out in typical outpatient clinic conditions which focused on cognitions. A randomised controlled trial compares 10 sessions of manualised cognitive behavioural treatment with a 12-week waiting list for adolescents and children with OCD. Assessors were blind to treatment allocation. 21 consecutive patients with OCD aged between 9 and 18 years were recruited. The group who received treatment improved more than a comparison group who waited for 3 months. The second group was treated subsequently using the same protocol and made similar gains. In conclusion, CBT can be delivered effectively to young people with OCD in typical outpatient settings.

A year-long multifaceted hand-hygiene campaign entitled Clean Hands for Life targeting individual, environmental and organisational factors that influence healthcare worker (HCW) hand-hygiene behaviour was implemented in 36 acute and long-term care facilities in Vancouver Coastal Health region. The campaign involved rotation of ten novel posters, two poster contests, and distribution of multiple promotional items. A social marketing approach was used to implement and monitor the effectiveness of the campaign. Evaluation included quality assurance surveys, staff surveys (baseline, mid- and post-campaign), and focus groups. A total of 141 poster contest submissions was received, 5452 staff surveys completed and 14 focus groups conducted. Overall knowledge of the importance of hand-hygiene and intention to clean hands was high at baseline. No significant differences were observed when mid- and post-campaign scores were compared to baseline. The majority (89.5%) of HCWs reported that they preferred soap and water over alcohol hand gel. A significant increase in the self-reported use of hand-hygiene products was observed particularly among HCWs not providing direct patient care. Barriers to hand-hygiene included inappropriate placement of sinks, traffic flow issues, inadequately stocked washrooms, workload and time constraints. Organisational support was visible throughout the campaign. The results showed that social marketing is an effective approach in engaging HCWs. Hand-hygiene campaigns that focus almost exclusively on increasing awareness among HCWs may not be as successful as multifaceted campaigns or campaigns that target identified barriers to hand-hygiene., (Copyright 2009 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved.)

We determined the effect of claudication pain on temporal and spatial gait characteristics, and on ambulatory symmetry at preferred and rapid self-selected walking paces in patients with unilateral peripheral arterial disease (PAD). Twenty-eight patients with PAD limited by intermittent claudication were studied. Patients ambulated at their preferred and rapid paces over a 7.3-meter portable gait mat system while they were pain-free and after experiencing claudication pain. The order of the pain-free and painful walking trials was randomized, and the following gait parameters were obtained: velocity, cadence, stride length, swing time, stance time, single-support time, and double-support time. During the self-selected rapid pace, patients walked 3% slower (p = 0.020) while in pain due to a 3% shorter stride length (p < 0.001), and they were in double-stance longer (p = 0.024). Claudication pain in the symptomatic leg resulted in an increase in single-stance (p = 0.007). Furthermore, gait became asymmetrical with pain, as the symptomatic leg spent a higher percentage of the gait cycle in the swing phase (p < 0.01) and lower percentages in stance (p < 0.01) and single-stance (p < 0.01) than the asymptomatic leg. Ambulation was symmetrical for all measures during the pain-free trial. In conclusion, claudication pain slows ambulatory velocity at preferred and rapid paces, and increases asymmetry when ambulatory function is challenged with rapid walking. The reduced ambulatory speed with the development of claudication pain may be an adaptation to elicit a safer and less destabilizing gait pattern.

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is an emerging pathogen first described among individuals with no contact with health care facilities. The purpose of this study was to determine the proportion of CA-MRSA, defined by pulsed field gel electrophoresis (PFGE), in MRSA skin and soft tissue infections presenting to the Emergency Department (ED). We also aimed to describe the laboratory and clinical characteristics of CA-MRSA infections. From June 1, 2001 to May 30, 2005, MRSA isolates from skin and soft tissue infections presenting to the ED were reviewed. They were characterized by antibiotic susceptibilities and PFGE, and the presence of staphylococcal cassette chromosome (SCC) mec type IVa and Panton-Valentine leukocidin (PVL) genes was assessed on representative isolates. The medical records were reviewed to define risk factors. There were 95 isolates available for analysis, of which 58 (61%) were CMRSA-10 (USA-300), the predominant clone from 2003 onward. All representative isolates (24%) tested in this group had PVL genes and SCCmec type IVa. Their antibiogram showed 100% susceptibility to trimethoprim-sulfamethoxazole, rifampin, and fusidic acid, and 79% to clindamycin. Clinical comparison of CMRSA-10 vs. hospital PFGE type strains showed 22% vs. 60%, respectively, for recent antibiotic use (p < 0.0001), 26% vs. 6%, respectively, for intravenous drug use (p < 0.05), and 57% vs. 6%, respectively, for soft tissue abscess (p < 0.001). CMRSA-10 is a major pathogen in skin and soft tissue abscesses in our ED. It has a characteristic susceptibility, and was associated with intravenous drug use, but not with recent antibiotic usage., (Copyright 2010 Elsevier Inc. All rights reserved.)

Ataxia-telangiectasia mutated (ATM) is known to play a central role in effecting the DNA damage response that protects somatic cells from potentially harmful mutations, and in this role it is a key anti-cancer agent. However, it also promotes repair of therapeutic damage (e.g. radiotherapy) and so frustrates the efficacy of some treatments. A better understanding of the mechanisms of ATM regulation is therefore important both in prevention and treatment of disease. While progress has been made in elucidating the key signal transduction pathways that mediate damage response in somatic cells, relatively little is known about whether these function similarly in pluripotent embryonic stem (ES) cells where ATM is also implicated in our understanding of adult stem cell ageing and in improvements in regenerative medicine. There is some evidence that different mechanisms may operate in ES cells and that our understanding of the mechanisms of ATM regulation is therefore incomplete. We investigated the behaviour of the damage response signalling pathway in mouse ES cells. We subjected the cells to the DNA-damaging agent doxorubicin, a drug that induces double-strand breaks, and measured ATM expression levels. We found that basal ATM gene expression was unaffected by doxorubicin treatment. However, following ATM kinase inhibition using a specific ATM inhibitor, we observed a significant increase in ATM and ataxia-telangiectasia and Rad3 related transcription. We demonstrate the use of a dynamical modelling approach to show that these results cannot be explained in terms of known mechanisms. Furthermore, we show that the modelling approach can be used to identify a novel feedback process that may underlie the anomalies in the data. The predictions of the model are consistent both with our in vitro experiments and with in vivo studies of ATM expression in somatic cells in mice, and we hypothesize that this feedback operates in both somatic and ES cells in vivo. The results point to a possible new target for ATM inhibition that overcomes the restorative potential of the proposed feedback.

Promoterless gene trap vectors have been widely used for high-efficiency gene targeting and random mutagenesis in embryonic stem (ES) cells. Unfortunately, such vectors are only effective for genes expressed in ES cells and this has prompted the development of expression-independent vectors. These polyadenylation (poly A) trap vectors employ a splice donor to capture an endogenous gene's polyadenylation sequence and provide transcript stability. However, the spectrum of mutations generated by these vectors appears largely restricted to the last intron of target loci due to nonsense-mediated mRNA decay (NMD) making them unsuitable for gene targeting applications. Here, we present novel poly A trap vectors that overcome the effect of NMD and also employ RNA instability sequences to improve splicing efficiency. The set of random insertions generated with these vectors show a significantly reduced insertional bias and the vectors can be targeted directly to a 5' intron. We also show that this relative positional independence is linked to the human beta-actin promoter and is most likely a result of its transcriptional activity in ES cells. Taken together our data indicate that these vectors are an effective tool for insertional mutagenesis that can be used for either gene trapping or gene targeting.

Embryonic stem (ES) cells have high self-renewal capacity and the potential to differentiate into a large variety of cell types. To investigate gene networks operating in pluripotent ES cells and their derivatives, the "Functional Genomics in Embryonic Stem Cells" consortium (FunGenES) has analyzed the transcriptome of mouse ES cells in eleven diverse settings representing sixty-seven experimental conditions. To better illustrate gene expression profiles in mouse ES cells, we have organized the results in an interactive database with a number of features and tools. Specifically, we have generated clusters of transcripts that behave the same way under the entire spectrum of the sixty-seven experimental conditions; we have assembled genes in groups according to their time of expression during successive days of ES cell differentiation; we have included expression profiles of specific gene classes such as transcription regulatory factors and Expressed Sequence Tags; transcripts have been arranged in "Expression Waves" and juxtaposed to genes with opposite or complementary expression patterns; we have designed search engines to display the expression profile of any transcript during ES cell differentiation; gene expression data have been organized in animated graphs of KEGG signaling and metabolic pathways; and finally, we have incorporated advanced functional annotations for individual genes or gene clusters of interest and links to microarray and genomic resources. The FunGenES database provides a comprehensive resource for studies into the biology of ES cells.

Introduction: Children's hospices have the facilities to enable a child to remain at the hospice following their death until the time of the funeral if desired by the family. The use of cold bedrooms (or beds) to reduce the rate of the body's physical deterioration enables the family to have unrestricted access and close proximity to the child throughout the 24-hour period., Aim: To explore how bereaved families experience the child remaining in a cold bedroom following the child's death in the period January 2002-March 2005., Objective: To survey all the families whose child had been cared for in a cold bedroom in one children's hospice in South-East England (n=34)., Method: A retrospective cross-sectional survey using a postal questionnaire was conducted. Questionnaires were sent to the 31 bereaved families who were considered eligible for participation., Response: Sixteen completed questionnaires were returned (51.6%); four families declined participation (12.9%); eleven families did not reply (35.5%)., Results: The experiences of sixteen families were obtained. The families expressed that they found the experience physically, practically and emotionally supportive, as they were able to continue to act as the child's parents, to choose and control how their child's care occurred, to say their farewells at their own pace and to plan the funeral of their choice. These results must be interpreted with the clear recognition that the experiences of 48.4% of the sample are unknown. Reasons for non-participation were explored., Conclusion: The study has methodological limitations but presents an investigation into the experiences of parents whose child has been cared for in a cold bedroom. These families all described the experience positively.

Hematopoietic stem cells derived from human embryonic stem cells (hESCs) could provide a therapeutic alternative to bone marrow transplants, but the efficiency of currently available derivation protocols is low. In this study, we investigated whether coculture with monolayers of cells derived from mouse AGM and fetal liver, or with stromal cell lines derived from these tissues, can enhance hESC hematopoietic differentiation. We found that under such conditions hESC-derived differentiating cells formed early hematopoietic progenitors, with a peak at day 18-21 of differentiation that corresponded to the highest CD34 expression. These hESC-derived hematopoietic cells were capable of primary and secondary hematopoietic engraftment into immunocompromised mice at substantially higher levels than described previously. Transcriptional and functional analysis identified TGF-beta1 and TGF-beta3 as positive enhancers of hESC hematopoietic differentiation that can further stimulate this process when added to the culture. Overall, our findings represent significant progress toward the goal of deriving functional hematopoietic stem cells from hESCs.

Purpose: To investigate intracortical inhibition and facilitation in response to unilateral dominant, nondominant and bilateral biceps activation and short-term upper extremity training in right- and left-handed adults., Methods: Paired-pulse transcranial magnetic stimulation was used to measure intracortical excitability in motor dominant and nondominant cortices of 26 nondisabled adults. Neural facilitation and inhibition were measured in each hemisphere during unilateral dominant, nondominant and bilateral arm activation and after training in each condition., Results: No differences were seen between right- and left-handed subjects. Intracortical facilitation and decreased inhibition were seen in each hemisphere with unilateral activation/training of contralateral muscles and bilateral muscle activation/training. Persistent intracortical inhibition was seen in each hemisphere with ipsilateral muscle activation/training. Inhibition was greater in the nondominant hemisphere during dominant hemisphere activation (dominant arm contraction)., Conclusion: Strongly dominant individuals show no difference in intracortical responses given handedness. Intracortical activity with unilateral and bilateral arm activation and short-term training differs based on hemispheric dominance, with the motor dominant hemisphere exerting a larger inhibitory influence over the nondominant hemisphere. Bilateral activation and training have a disinhibitory effect in both dominant and nondominant hemispheres.

Event related desynchronization (ERD) allows evaluation of brain signals in multiple frequency dimensions. The purpose of this study was to determine left hemispheric non-primary motor cortex differences at varying frequencies of premovement ERD for similar movements by end-effectors of the upper and lower extremities. We recorded 32-channel electroencephalography (EEG) while subjects performed self-paced right ankle dorsiflexion and wrist extension. Electromyography (EMG) was recorded over the tibialis anterior and extensor carpi ulnaris. EEG was analyzed for premovement ERD within the alpha (8-12 Hz), low beta (13-18 Hz) and high beta (18-22 Hz) frequencies over the premotor, motor, and sensory areas of the left and mesial cortex from -1.5 to 0 s before movement. Within the alpha and high beta bands, wrist movements showed limited topography, but greater ERD over posterior premotor cortex areas. Alpha ERD was also significantly greater over the lateral motor cortex for wrist movements. In the low beta band, wrist movements provided extensive ERD differences to include the left motor and mesial/lateral premotor areas, whereas ankle movements showed only limited ERD activity. Overall, alpha and high beta activity demonstrated distinctions that are consistent with mapping of wrist and ankle representations over the sensorimotor strip, whereas the low beta representation demonstrated the clearest distinctions between the limbs over widespread brain areas, particularly the lateral premotor cortex. This suggests limited leg premovement activity at the dorsolateral premotor cortex. Low beta ERD may be reflect joint or limb specific preparatory activity in the premotor area. Further work is required to better evaluate the extent of this low beta activity for multiple comparative joints.

Objective: To establish the instantaneous relative risk (RR) of death associated with individual antipsychotic drugs, carbamazepine and sodium valproate for those 65 years and older., Methods: Subjects dispensed antipsychotic drugs, sodium valproate or carbamazepine in 2003 or 2004 were analyzed as incident (N = 16,634) or prevalent (N = 9,831) users. Survival curves, mortality rates, and Cox proportional hazards models over two time periods were used to explore risk of death. The models were adjusted for age, sex, residential status, and psychotropic and medical drug dispensing. Olanzapine subjects were the reference group in the Cox regression. Subanalyses were performed for incident subjects with more than 30 days of follow-up and those dispensed cholinesterase inhibitors., Results: In the adjusted Cox proportional hazards models, haloperidol dispensing was consistently associated with an increased risk of death compared with olanzapine users (relative risk [RR] for incident users: 2.26, 95% confidence intervals (CI): 2.08-2.47; Wald statistic: 345.36, df = 1, p < or =0.001). There was some evidence of decreased survival with dispensing of higher haloperidol doses, although confounding by medical comorbidity cannot be excluded. Chlorpromazine (RR: 1.39, 95% CI: 1.15-1.67; Wald statistic: 12.08, df = 1, p <0.001) and risperidone (RR: 1.23, 95% CI: 1.07-1.40; Wald statistic: 9.12, df = 1, p = 0.003) dispensing were associated with increased risk of death in incident users., Conclusion: These results should be interpreted cautiously because haloperidol and chlorpromazine are used in broader clinical contexts. However, in the absence of data from randomized trials, the safety profile of haloperidol should not be assumed to be benign. Antipsychotic drugs should not be studied as an aggregated group because their associated risks are not uniform.

Objective: To establish the instantaneous relative risk (RR) associated with the dispensing of individual antipsychotic drugs, carbamazepine and valproate for those > or = 65 years who resided in an aged care facility., Method: The risk of death for incident users of antipsychotic drugs, carbamazepine and valproate in 2003 or 2004 who resided in an aged care facility was established using mortality rates and Cox proportional hazards models over two time periods. The regression models were adjusted for age, gender, medical and psychotropic drug dispensing, and a measure of overall medical comorbidity. Olanzapine users formed the referent group., Results: Haloperidol and chlorpromazine use were associated with the highest death rates. The instantaneous RR for those dispensed haloperidol was 1.67 (95% confidence intervals (CI) = 1.50-1.84, p < 0.001) and for chlorpromazine it was 1.75 (95%CI = 1.31-2.34, p < 0.001). The RR of death for haloperidol and chlorpromazine was higher in the regression model restricted to 60 days follow up (haloperidol RR = 2.17, 95%CI = 1.86-2.53, p < 0.001, chlorpromazine RR = 2.72, 95%CI = 1.84-4.01)., Conclusions: The increased risk associated with haloperidol and chlorpromazine dispensing should be interpreted cautiously because confounding by medical illness cannot be excluded despite adjusting the model for multiple variables. This study supports the findings from other data linkage studies that atypical antipsychotic medications are not associated with increased risk of death compared with conventional antipsychotic drugs.

Gene trapping is an insertional mutagenesis strategy that allows for simultaneous gene identification and mutation in embryonic stem (ES) cells. Gene trap vectors both disrupt coding sequence and report on the genes' endogenous expression. The most popular gene trap reporter to date combines beta-galactosidase expression with neomycin resistance in a fusion protein known as beta-geo. Here we describe a refinement to this reporter that also incorporates real time fluorescent readouts. We have constructed a series of gene trap vectors incorporating a novel tripartite fusion protein consisting of EGFP, beta-galactosidase, and the neomycin or hygromycin resistance activities. Our results indicate that these triple fusions can function efficiently as reporters of endogenous trapped gene expression and subcellular localization. We show that these fusion proteins constitute versatile gene trap reporters whose activity can be detected in real time by fluorescence and in fixed tissue with a sensitive enzymatic activity., ((c) 2007 Wiley-Liss, Inc.)

Objectives: To explore the odds ratios (ORs) of death associated with antipsychotic (AP) medications dispensed to elderly subjects., Method: Subjects were veterans and war widows 65 years and older dispensed an AP drug in 2001 in NSW or ACT. For all subjects, dispensing records for AP medication, benzodiazepines, lithium, carbamazepine, sodium valproate and antidepressant medication were extracted and combined with age, gender and date of death. A study date was allocated, either the date of death or a random date from 1.5.01 to 31.12.01. Subjects dispensed an AP in 2001, but not dispensed an AP or other psychotropic medication in the 120 days prior to their study date, formed a reference group. Psychotropic dispensing in the 120 days prior to the study date was analysed using nested logistic regression models to produce ORs of death associated with various AP drugs. The ORs for risperidone, olanzapine and pericyazine were compared. Haloperidol ORs were established for those dispensed the drug 0-30 days prior to study date or 31-120 days prior to the study date., Results: The ORs associated with haloperidol, olanzapine, risperidone, pericyazine, thioridazine and chlorpromazine were significant when compared with the reference group. Odds ratios for all three haloperidol periods were significant when compared with olanzapine, risperidone and pericyazine 120 day ORs. Although there was a trend favouring olanzapine when compared with risperidone, the difference in the ORs failed to reach significance (p=0.066)., Conclusions: Haloperidol is associated with significantly higher mortality rates than other AP medication but it is not clear whether this represents drug toxicity or the medical conditions for which it was dispensed. There was no evidence that the conventional AP pericyazine was associated with a higher mortality rate than olanzapine or risperidone.

Stroke is a major cause of disability in the US, leaving most survivors with abnormal motor function, often resulting in hemiparetic gait. Quality of gait in this population has been well characterized by measures of velocity, though velocity alone provides only a general index of functional mobility. Researchers and clinicians should continue to develop a complete characterization of behavioral alterations, but should also work to identify the neuromechanical processes underlying the loss and recovery of locomotor function. We hypothesized that selected foot center of pressure (CoP) measures would show a predictive relationship with hemiparetic gait velocity, a standard clinical metric of locomotor capability, thus providing insight into the relationship between neuromotor control and function. Thirty-three chronic stroke survivors (67+/-10 years) were evaluated during walking at a self-selected speed. Patients wore pressure sensitive shoe insoles and completed 15 steady-state gait cycles over an instrumented gait mat. CoP parameters and walking velocity were measured during each cycle. Multiple regression analyses were used to model all combinations of CoP and interlimb symmetry parameters as predictor variables of gait velocity. Eleven CoP and symmetry parameters were selected in a final regression model, and provided a robust prediction of hemiparetic gait velocity (R(adj)(2)=0.90) in this group of chronic stroke patients. These results indicate that bilateral foot CoP measures, especially those representing variability of foot CoP control, not only index locomotor function, but may also have the potential to provide information about the underlying control properties of the stroke-injured neuromuscular system., (Copyright 2005 Elsevier B.V.)

Finger tapping involves 3 important features: time, spatial amplitude, and frequency. In classical analysis, investigators examine timing parameters; in spectral analysis, they examine frequency parameters. Both types of analysis are based on stationary tap information. The authors propose that time-frequency analysis is a useful tool for analyzing nonstationary finger tapping. They describe the method and give examples of frequency modulation, age difference, and speed transition that demonstrate additional insights one can gain by using this analysis.

Recent work has indicated that adult bone marrow-derived cells have the ability to contribute to both the haematopoietic system and other organs. Haematopoietic reconstitution by whole bone marrow and selected but not fully characterised cell populations have resulted in reports indicating high-level repopulation of lung epithelia. The well-characterised cells from the side population have a robust ability for haematopoietic reconstitution. We have used freshly isolated side population cells derived from ROSA26 adult bone marrow and demonstrate that despite being unable to contribute to embryos following blastocyst injection, or air liquid interface cultures or denuded tracheal xenografts, they could contribute to the tracheal epithelium in vivo. Epithelial damage is reported to be important in encouraging the recruitment of marrow-derived stem cells into non-haematopoietic organs. Here we demonstrate that mice engrafted with side population cells have donor-derived cells present in the epithelial lining of the trachea following damage and repair. Donor-derived cells were found at a frequency of 0.83%. Widefield and confocal microscopy revealed donor cells that expressed cytokeratins, indicative of cells of an epithelial nature. These results imply that SP haematopoietic stem cells from the bone marrow do not have the ability to contribute to airway epithelia themselves but require factors present in vivo to allow them to acquire characteristics of this tissue.

Lower extremity paresis poses significant disability to chronic stroke survivors. Unlike for the upper extremity, cortical adaptations in networks controlling the paretic leg have not been characterized after stroke. Here, the hypotheses are that brain activation associated with unilateral knee movement in chronic stroke survivors is abnormal, depends on lesion location, and is related to walking ability. Functional magnetic resonance imaging of unilateral knee movement was obtained in 31 patients 26.9 months (mean, IQ range: 11.3-68.1) after stroke and in 10 age-matched healthy controls. Strokes were stratified according to lesion location. Locomotor disability (30 ft walking speed) did not differ between patient groups (9 cortical, 12 subcortical, 10 brainstem lesions). Significant differences in brain activation as measured by voxel counts in 10 regions of interest were found between controls and patients with brainstem (P = 0.006) and cortical strokes (P = 0.002), and between subcortical and cortical patients (P = 0.026). Statistical parametric mapping of data per group revealed similar activation patterns in subcortical patients and controls with recruitment of contralateral primary motor cortex (M1), supplementary motor area (SMA), and bilateral somatosensory area 2 (S2). Cortical recruitment was reduced in brainstem and cortical stroke. Better walking was associated with lesser contralateral sensorimotor cortex activation in brainstem, but stronger recruitment of ipsilateral sensorimotor and bilateral somatosensory cortices in subcortical and cortical patients, respectively. A post hoc comparison of brainstem patients with and without mirror movements (50%) revealed lesser recruitment of ipsilateral cerebellum in the latter. Subcortical patients with mirror movements (58%) showed lesser bilateral sensorimotor cortex activation. No cortical patient had mirror movements. The data reveal adaptations in networks controlling unilateral paretic knee movement in chronic stroke survivors. These adaptations depend on lesion location and seem to have functional relevance for locomotion.

It has been reported that DNA methyltransferase 1-deficient (Dnmt1-/-) embryonic stem (ES) cells are hypomethylated (20% CpG methylation) and die through apoptosis when induced to differentiate. Here, we show that Dnmt[3a-/-,3b-/-] ES cells with just 0.6% of their CpG dinucleotides behave differently: the majority of cells within the culture are partially or completely blocked in their ability to initiate differentiation, remaining viable while retaining the stem cell characteristics of alkaline phosphatase and Oct4 expression. Restoration of DNA methylation levels rescues these defects. Severely hypomethylated Dnmt[3a-/-,3b-/-] ES cells have increased histone acetylation levels, and those cells that can differentiate aberrantly express extraembryonic markers of differentiation. Dnmt[3a-/-,3b-/-] ES cells with >10% CpG methylation are able to terminally differentiate, whereas Dnmt1-/- ES cells with 20% of the CpG methylated cannot differentiate. This demonstrates that successful terminal differentiation is not dependent simply on adequate methylation levels. There is an absolute requirement that the methylation be delivered by the maintenance enzyme Dnmt1.

Recovery of motor function after stroke is associated with reorganization in central motor networks. Functional imaging has demonstrated recovery-dependent alterations in brain activation patterns when compared to healthy controls. These alterations are variable across stroke subjects. Factors identified as contributing to this variability are the degree of functional impairment, the time interval since stroke, and rehabilitative therapies. Here, the hypothesis is tested that lesion location influences the activation patterns. Using functional magnetic resonance imaging, the objective was to characterize similarities or differences in movement-related activation patterns in patients chronically disabled by cortical plus subcortical or subcortical lesions only. Brain activation was mapped during paretic and non-paretic movement in 11 patients with subcortical stroke, in nine patients with stroke involving sensorimotor cortex, and in eight healthy volunteers. Patient groups had similar average motor deficit as measured by a battery of scores and strength measures. Substantial differences between patients groups were found in activation patterns associated with paretic limb movement: whereas contralateral motor cortex, ipsilateral cerebellum (relative to moving limb), bilateral mesial (cingulate, SMA), and perisylvian regions were active in subcortical stroke, cortical patients recruited only ipsilateral postcentral mesial hemisphere regions, and areas at the rim of the stroke cavity. For both groups, activation in ipsilateral postcentral cortex correlated with motor function; in subcortical stroke, the same was found for mesial and perisylvian regions. Overall, brain activation in cortical stroke was less, while in subcortical patients, more than in healthy controls. For non-paretic movement, activation patterns were similar to control in cortical patients. In subcortical patients, however, activation patterns differed: the activation of non-paretic movement was similar to that of paretic movement (corrected for side). The data demonstrate more differences than similarities in the central control of paretic and non-paretic limb movement in patients chronically disabled by subcortical versus cortical stroke. Whereas standard motor circuitry is utilized in subcortical stroke, alternative networks are recruited after cortical stroke. This finding proposes lesion-specific mechanisms of reorganization. Optimal activation of these distinct networks may require different rehabilitative strategies.

Background & Aims: Studies have indicated that stem cells have unexpected plasticity and can differentiate down a multitude of nonhematopoietic cell lineages in rodents. Our aim was to identify whether human cord blood cells, which are a rich source of stem cells, would be able to differentiate into hepatocytes when infused into nonobese diabetic-severe combined immunodeficient (NOD-SCID) mice. We also wanted to test whether such differentiated cells were the result of cellular fusion or true stem cell transdifferentiation., Methods: Unsorted mononuclear cell preparations of human cord blood were infused into sublethally irradiated NOD-SCID mice. After death, immunohistologic analysis of murine livers was performed using human specific hepatocyte, biliary, and endothelial markers. Fluorescent in situ hybridization (FISH) for mouse and human DNA was also performed., Results: We show that human cord blood cells have the ability to engraft into NOD-SCID liver and become mature hepatocytes. We were unable to identify any biliary or endothelial differentiation. Furthermore, we do not detect any evidence of cell fusion in any of the human cells found in the mouse liver, suggesting that human cord blood cells are capable of true transdifferentiation into hepatocytes in vivo., Conclusions: We conclude that hepatocytes can derive from human cord blood cells when infused into NOD-SCID mice in the absence of fusion. The demonstration that human stem cell differentiation can occur in this murine model permits comprehensive study of human stem cell plasticity in vivo.

The alpha-fetoprotein gene (Afp) is a member of a multigenic family that comprises the related genes encoding albumin, alpha-albumin, and vitamin D binding protein. The biological role of this major embryonic serum protein is unknown although numerous speculations have been made. We have used gene targeting to show that AFP is not required for embryonic development. AFP null embryos develop normally, and individually transplanted homozygous embryos can develop in an AFP-deficient microenvironment. Whereas mutant homozygous adult males are viable and fertile, AFP null females are infertile. Our analyses of these mice indicate that the defect is caused by a dysfunction of the hypothalamic/pituitary system, leading to anovulation.

It was shown recently that functional activation across brain motor areas during locomotion and foot movements are similar but differ substantially from activation related to upper extremity movement (Miyai [2001]: Neuroimage 14:1186-1192). The activation pattern may be a function of the behavioral context of the movement rather than of its mechanical properties. We compare motor system activation patterns associated with isolated single-joint movement of corresponding joints in arm and leg carried out in equal frequency and range. Eleven healthy volunteers underwent BOLD-weighted fMRI while performing repetitive elbow or knee extension/flexion. To relate elbow and knee activation to the well-described patterns of finger movement, serial finger-to-thumb opposition was assessed in addition. After identifying task-related voxels using statistical parametric mapping, activation was measured in five regions of interest (ROI; primary motor [M1] and somatosensory cortex [S1], premotor cortex, supplementary motor area [SMA] divided into preSMA and SMA-proper, and cerebellum). Differences in the degree of activation across ROIs were found between elbow and knee movement. SMA-proper activation was prominent for knee, but almost absent for elbow movement (P < 0.05); finger movement produced small but constant SMA-proper activation. Ipsilateral M1 activation was detected during knee and finger movement, but was absent for the elbow task (P < 0.05). Knee movement showed less lateralization in M1 and S1 than other tasks (P < 0.05). The data demonstrate that central motor structures contribute differently to isolated elbow and knee movement. Activation during knee movement shows similarities to gait-related activation patterns., (Copyright 2002 Wiley-Liss, Inc.)

A new DNA virus, referred to as SEN virus (SEN V), has been isolated and is associated with blood-product transfusion and possibly Non A to Non E hepatitis. We performed a cross-sectional analysis of SEN V in liver transplant recipients at our center. Polymerase chain reaction was used to test for 2 genotypes of SEN V (SEN V:C/H and SEN V:D) in 58 unselected patients. Comparisons were made between SEN V--positive and SEN V--negative groups in terms of age, time posttransplantation, indications for transplantation, serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, and cytomegalovirus and Epstein-Barr virus status. Thirty of 58 transplant recipients (51.7%) were SEN V positive; 15.5% were positive for SEN V:C/H, 24.1% for SEN:D, and 12.1% for both strains. No significant differences were found based on primary indication for transplantation, including hepatitis C virus (HCV). Of the 14 of 21 patients with HCV seropositivity and HCV reinfection, 79% were positive for SEN V (P =.02). There was no difference in the proportion of patients with abnormal serum ALT and/or AST levels. A trend for the SEN V--positive group to have a greater mean ALT level (82 v 41 U/L; P =.067) was attributable to the subgroup with HCV recurrence because there was no difference in mean ALT levels (34.9 v 34.5 U/L; P =.968) in non--HCV-infected transplant recipients. Even in the subgroup (n = 14) with recurrent HCV, there was no statistically significant difference in mean ALT levels (140 v 105 U/L; P =.665). Age and cytomegalovirus or Epstein-Barr virus status were not significantly different between the 2 groups, but a significant difference in posttransplantation time was noted (16.8 v 32 months; P =.021). We conclude that SEN V is common among liver transplant recipients but does not appear to cause graft dysfunction as an isolated agent. There is a suggestion that SEN V may be associated with HCV recurrence, but we did not detect biochemical differences attributable to SEN V.