Role of articulatory motor networks in perceptual categorization of speech signals: a 7T fMRI study.

Speech and language processing involve complex interactions between cortical areas necessary for articulatory movements and auditory perception and a range of areas through which these are connected and interact. Despite their fundamental importance, the precise mechanisms underlying these processes are not fully elucidated. We measured BOLD signals from normal hearing participants using high-field 7 Tesla fMRI with 1-mm isotropic voxel resolution. The subjects performed 2 speech perception tasks (discrimination and classification) and a speech production task during the scan. By employing univariate and multivariate pattern analyses, we identified the neural signatures associated with speech production and perception. The left precentral, premotor, and inferior frontal cortex regions showed significant activations that correlated with phoneme category variability during perceptual discrimination tasks. In addition, the perceived sound categories could be decoded from signals in a region of interest defined based on activation related to production task. The results support the hypothesis that articulatory motor networks in the left hemisphere, typically associated with speech production, may also play a critical role in the perceptual categorization of syllables. The study provides valuable insights into the intricate neural mechanisms that underlie speech processing.

The effects of information platform-based nursing on preventing venous thromboembolism in patients with hip fractures.

PURPOSE: Venous thromboembolism (VTE) is a major health issue among hip fracture patients. This study aimed to develop an information platform based on a mobile application and then evaluate whether information platform-based nursing could improve patient's drug compliance and reduce the incidence of VTE in hip fracture patients. METHODS: This study retrospectively analyzed hip fracture patients who were treated with conventional prevention and intervention methods for VTE (control group) between January 2008 and November 2012, and prospectively analyzed hip fracture patients who were treated with nursing intervention based on the information platform (study group) between January 2016 and September 2017. All the patients included in the both groups were hip fracture patients who had an age over 50 years, treated with surgery, and hospitalized ≥ 48 h. Patients were excluded if they admitted to hospital due to old fractures, had a severe bleeding after 72 h of admission, diagnosed with any type of VTE, or refused to participate in the study. The information platform was divided into medical, nursing, and patient interface. Based on the information platform, medical practitioners and nurses could perform risk assessments, monitoring management and early warnings, preventions and treatments, health educations, follow-up, and other aspects of nursing interventions for patients. This study compared essential characteristics, drug compliance, VTE occurrence, and mean length of hospitalization between the two groups. Besides, a subgroup analysis was performed in the study group according to different drug compliances. SPSS 18.0 software (IBM Corp., NY, and USA) was used for statistical analysis. RESULTS: Altogether 1177 patients were included in the control group, and 491 patients in the study group. Regarding baseline data, patients in the study group had more morbidities than those in the control group (p < 0.05). The difference of drug compliance between the two groups was statistically significant (p < 0.001): 761 (64.7%) of the patients in the control group and only 30 (6.1%) patients in the study group had poor drug compliance. In terms of VTE, 10.7% patients (126/1177) in the control group had VTE, and the rate in the study group was 7.1% (35/491), showing a statistically significant difference (p = 0.02). Moreover, the average length of hospitalization in the study group was also significantly lower than that in the control group (10.4 days vs. 13.7 days, p < 0.001). Subgroup analyses of the study group showed that the incidence of VTE in patients with poor, partial, and good compliances were 56.7% (17/30), 5.8% (10/171), and 2.8% (8/290), respectively, revealing a significantly huge difference (p < 0.001). CONCLUSIONS: Poor drug compliance leads to higher VTE occurrence. The information platform-based nursing can effectively improve the compliance of hip fracture patients and thus considerably reduce the incidence of VTE. The mobile application may be an effective tool to prevent VTE in hip fracture patients.

Differential Association of Serum BDNF With Poststroke Depression and Poststroke Anxiety.

OBJECTIVES: To investigate the correlation between brain-derived neurotrophic factor (BDNF) and risk factors, as well as functional outcome in poststroke depression (PSD) or poststroke anxiety (PSA). DESIGN: Cohort study. SETTING: Stroke patients admitted to an urban rehabilitation hospital. PARTICIPANTS: Stroke patients (N=162) without any previous history of depression and anxiety. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Sociodemographic information and comorbidities were recorded during hospital admission. Functional outcomes were assessed using FIM scores at time of admission and discharge. The influence of various factors such as BDNF and patient characteristics on functional outcome was investigated. Single-factor effect was examined using simple logistic regression, as was multi-factor effect using multiple logistic regression. The goodness-of-fit of those regression models was evaluated by the integrated area under ROC curve. RESULTS: PSD was diagnosed in 61 (37.7%) patients, and PSA was diagnosed in 40 (24.7%). Multiple logistic analysis showed that BDNF, divorce or separation, and history of smoking were significantly associated with the occurrence of PSD but not with the occurrence of PSA. The model combining low BDNF level and divorce or separation improved the prediction for PSD. Among the variables analyzed for prediction of functional outcome, serum BDNF had a minimum correlation with motor FIM scores in PSD but no significant correlation with motor FIM scores in PSA. CONCLUSIONS: BDNF is a valuable prediction for the occurrence of PSD but not for PSA. More strikingly, ischemic stroke patients who are divorced or separated with low serum BDNF have a much higher risk for PSD. BDNF has a minimum correlation with motor function outcome in PSD but no significant correlation with motor outcome in PSA.

User testing of the psychometric properties of pictorial-based disability assessment Longshi Scale by healthcare professionals and non-professionals: a Chinese study in Shenzhen.

OBJECTIVE: The aim of this study was to validate a novel pictorial-based Longshi Scale for evaluating a patient's disability by healthcare professionals and non-professionals. DESIGN: Prospective study. SETTING: Rehabilitation departments from a grade A, class 3 public hospital, a grade B, class 2 public hospital, and a private hospital and seven community rehabilitation centers. SUBJECTS: A total of 618 patients and 251 patients with functional disabilities were recruited in a two-phase study, respectively. MAIN MEASURES: Outcome measure: pictorial scale of activities of daily living (ADLs, Longshi Scale). Reference measure: Barthel Index. The Spearman correlation coefficient was used to analyze the validity of Longshi Scale against Barthel Index. RESULTS: In phase 1 study, from March 2016 to August 2016, the results demonstrated that the Longshi Scale was both reliable and valid (intraclass correlation coefficient based on two-way random effect (ICC2,1) = 0.877-0.974 for intra-rater reliability; ICC2,1 = 0.928-0.979; κ = 0.679-1.000 for inter-rater reliability; intraclass correlation coefficient based on one-way random effect (ICC1,1) = 0.921-0.984 for test-retest reliability and Spearman correlation coefficient = 0.836-0.899). In the second phase, in March 2018, results further demonstrated that the Longshi Scale had good inter-rater and intra-rater reliability among healthcare professionals and non-professionals including therapists, interns, and personal care aids (ICC1,1 = 0.822-0.882 on Day 1; ICC1,1 = 0.842-0.899 on Day 7 for inter-rater reliability). In addition, the Longshi Scale decreased assessment time significantly, compared with the Barthel Index assessment (P < 0.01). CONCLUSION: The Longshi Scale could potentially provide an efficient way for healthcare professionals and non-professionals who may have minimal training to assess the ADLs of functionally disabled patients.

Inflammatory Signaling in Post-Stroke Fatigue and Depression.

BACKGROUND: In the United States, stroke continues to be the cause for long-term disability. Of the patients with a first stroke, up to 75% will experience post-stroke fatigue (PSF) in the first year following stroke. PSF is one of the most disabling symptoms in stroke survivors; it decreases quality of life, increases mortality, and is a barrier to stroke rehabilitation. Given the incidence of stroke and the prevalence and detrimental impact of PSF on quality of life, independent living, and overall survival, efficient management of PSF must be a priority in stroke rehabilitation. The cause of PSF remains unknown. The burden of fatigue in stroke survivors is influenced by other stroke-related symptoms, most notably post-stroke depression (PSD). It is well known that stroke induces a systemic inflammatory response that is the trigger for sickness behavior, of which fatigue and depression are predominant symptoms. SUMMARY: To date, only a handful of studies have sought to explore the relationship between stroke-induced inflammation and PSF and PSD. In this review, we describe this evidence, highlight the strengths and weaknesses of these existing studies, and suggest further experiments that may further support the association between stroke-related inflammatory processes and stroke-related symptoms. Key Messages: The current concept and further research are important for a more specific therapeutic intervention for PSF and PSD.

Effects of Fluoxetine on Poststroke Dysphagia: A Clinical Retrospective Study.

BACKGROUND: To investigate whether fluoxetine improves poststroke dysphagia and to detect the potential relationship between serum brain-derived neurotrophic factor (BDNF) levels and fluoxetine effects. METHODS: In this retrospective study, 159 stroke patients who met our study criteria were included. In total, 110 patients were placed in the control group, and 49 patients were placed in the fluoxetine group. Demographic and clinical characteristics of the patients were collected for the baseline assessment. Functional independence measure scores and American speech-language-hearing association/functional communication measures scores for swallowing were collected to evaluate the patients' swallowing function. Patients' serums were collected at weeks 1 and 3 after admission, and serum BDNF levels were measured by enzyme-linked immunosorbent assay. T test, chi-squared test, and general linear model analysis were performed to determine the differences between the two groups. RESULTS: A significantly higher improvement of swallowing function was observed in the fluoxetine group compared with that of the control group (P = .023). In addition, a general linear model analysis showed that the treatment of fluoxetine has a statistically significant effect on swallowing improvement after adjustment of swallowing score on admission, stroke types, and interval between the onset of stroke and admission (P = .022, R2 = .46, adjusted R2 = .446). There is no significant difference in the change of serum BDNF levels in the two groups (P = .269). CONCLUSIONS: This study suggests that treatment with fluoxetine in stroke patients with dysphagia may improve swallowing function. A placebo-controlled, randomized clinical trial is warranted to confirm this finding.

Correlation of Fractional Anisotropy With Motor Recovery in Patients With Stroke After Postacute Rehabilitation.

OBJECTIVE: To investigate the relation between fractional anisotropy (FA), a suggested biomarker for tissue integrity, and motor recovery in patients with stroke after postacute rehabilitation. DESIGN: Retrospective study. SETTING: Acute rehabilitation hospital. PARTICIPANTS: Subjects (N=43) diagnosed with ischemic stroke (n=28) and hemorrhagic stroke (n=15). The average age for subjects was 68±14 years. INTERVENTIONS: Magnetic resonance imaging and diffusion tensor imaging were conducted on all patients. MAIN OUTCOME MEASURES: The admission and discharge motor subscores of the FIM were obtained from medical records, and relative gain was calculated using the Montebello Rehabilitation Factor Score (MRFS). K-means cluster analysis (K=3) using both the MRFS and the gain of the FIM motor subscore (ΔFIM) was performed. Analysis of variance was used to determine the difference in FA among the clusters. Spearman analysis was conducted to examine the relation between FA, ΔFIM, and MRFS in each cluster. RESULTS: FA was significantly higher in the clusters of good and moderate recovery in the corticospinal tract (CST), peduncle, and posterior limb of the internal capsule bilaterally (all P<.05) compared with the poor recovery group. Significant positive correlations were observed in multiple regions along the CST between FA, ΔFIM, and MRFS in the clusters of good and moderate recovery, but not in the poor recovery group. CONCLUSIONS: Our results showed an association between FA values within the corticospinal tract and motor recovery in patients with stroke undergoing postacute rehabilitation. This finding may help to identify novel targets for new interventions to promote stroke recovery.

Increased Th17/Treg Ratio in Poststroke Fatigue.

Fatigue is a major debilitating symptom after stroke. The biological mechanisms underlying poststroke fatigue (PFS) are unknown. We hypothesized that PSF is associated with an alteration in the balance between Th17 and Treg cells. To test this hypothesis we assessed fatigue in 30 stroke survivors using the Fatigue Scale for Motor and Cognitive Functions (FSMC). Peripheral blood was collected for assessment of Th17 and Treg cell populations and measurement of interleukin-10 (IL-10). Participants were dichotomized into severe fatigue (n = 14) and low-moderate fatigue (n = 16) groups by K-mean cluster analysis of FSMC scores. There were no group differences in age, gender, stroke type, stroke severity, or time since stroke. Stroke survivors in the severe fatigue group reported greater anxiety (p = 0.004) and depression (p = 0.001) than in the low-moderate fatigue group. The ratio of Th17 to Treg cells was significantly increased in the severe fatigue group relative to the mild-moderate fatigue group (p = 0.035). Serum levels of IL-10 negatively correlated withTh17/Treg ratio (r = -0.408, p = 0.025). Our preliminary findings suggest that an imbalance in the Th17/Treg ratio is associated with the severity of PSF.

Gene variations of ROCKs and risk of ischaemic stroke: the Women's Genome Health Study.

Recent animal and human studies have demonstrated the importance of the ROCK (RhoA/Rho-associated kinase) pathway in IsST (ischaemic stroke). Whether the genetic variation within ROCK-associated genes modulates the risk of IsST remains elusive. The association between 66 tSNPs [tagging SNPs (single nucleotide polymorphisms)] of three ROCK-associated genes [ROCK1, ROCK2 and ARHGEF10 (Rho guanine-nucleotide-exchange factor 10)] and the incidence of IsST was investigated in 23294 Caucasian female participants of the prospective WGHS (Women's Genome Health Study). All were free of known cancer and cardiovascular disease at baseline. During a 15-year follow-up period, 323 participants developed their first ever IsST. Multivariable Cox regression analysis was performed to investigate the relationship between genotypes and risk of IsST assuming an additive genetic model. Haplotype-block analysis was also performed. A total of ten tSNPs were associated with the risk of IsST (three in ARHGEF10 and seven in ROCK1; P<0.050). Further investigation using the haplotype-block analysis revealed a similar significant association of pre-specified haplotypes of ROCK1 with the risk of IsST (P=0.005). If corroborated in other large prospective studies, the findings of the present study suggest that genetic variation within the ROCK-associated pathway gene loci examined, and in particular ROCK1 gene variation, may influence the risk of IsST.

Organochlorine pesticides in the dust fall around Lake Chaohu, the fifth largest lake in China.

The residual levels of organochlorine pesticides (OCPs) in the dust fall around Lake Chaohu were measured using gas chromatography mass spectrometry from April 2010 to March 2011. The fluxes, components, temporal-spatial variations, and sources of OCPs were also analyzed. Twenty-one types of OCPs were detected in the dust fall samples around Lake Chaohu, with a total concentration of 51.54 ± 36.31 ng/g and a total flux of 10.01 ± 13.69 ng/(m(2) day). Aldrin (35.3 %), endosulfan (39.1 %), dichlorodiphenyltrichloroethanes (DDTs) (49.8 %), and isodrin (37.1 %) were the major OCPs in the spring, summer, autumn, and winter, respectively. Both the residual level and the flux were higher in the spring than in other seasons and higher at the outer lake sampling sites than inner lake sampling site. The potential source of the hexachlorcyclohexanes in the dust fall may be recent lindane usage. The DDTs mainly came from historical dicofol usage, and a significant input of DDT was found during April and June. The presence of endosulfan may be due to the present use of technical endosulfan. The aldrin in the dust might be due to its occasional usage, and isodrin may be a result of long-distance transport from other countries.

Individualized white matter connectivity of the articulatory pathway: An ultra-high field study.

In current sensorimotor theories pertaining to speech perception, there is a notable emphasis on the involvement of the articulatory-motor system in the processing of speech sounds. Using ultra-high field diffusion-weighted imaging at 7 Tesla, we visualized the white matter tracts connected to areas activated during a simple speech-sound production task in 18 healthy right-handed adults. Regions of interest for white matter tractography were individually determined through 7T functional MRI (fMRI) analyses, based on activations during silent vocalization tasks. These precentral seed regions, activated during the silent production of a lip-vowel sound, demonstrated anatomical connectivity with posterior superior temporal gyrus areas linked to the auditory perception of phonetic sounds. Our study provides a macrostructural foundation for understanding connections in speech production and underscores the central role of the articulatory motor system in speech perception. These findings highlight the value of ultra-high field 7T MR acquisition in unraveling the neural underpinnings of speech.

Mechanical digit sensory stimulation: a randomized control trial on neurological and motor recovery in acute stroke.

Background: Mechanical digit sensory stimulation (MDSS) is a novel therapy designed to accelerate the recovery of upper limb (including hand) function in patients with hemiplegia following a stroke. The primary goal of this study was to investigate the effect of MDSS on patients with acute ischemic stroke (AIS). Methods: Sixty-one inpatients with AIS were randomly divided into conventional rehabilitation group (RG) and stimulation group (SG), and the latter group received MDSS therapy. A healthy group consisting of 30 healthy adults was also included. The interleukin-17A (IL-17A), vascular endothelial growth factor A (VEGF-A), and tumor necrosis factor-alpha (TNF-α) plasma levels were measured in all subjects. The neurological and motor functions of patients were evaluated using the National Institutes of Health Stroke Scale (NIHSS), Mini-Mental State Examination (MMSE), Fugel-Meyer Assessment (FMA), and Modified Barthel Index (MBI). Results: After 12 days of intervention, the IL-17A, TNF-α, and NIHSS levels were significantly decreased, while the VEGF-A, MMSE, FMA, and MBI levels were significantly increased in both disease groups. No significant difference was observed between both disease groups after intervention. The levels of IL-17A and TNF-α were positively correlated with NIHSS but negatively correlated with MMSE, FMA, and MBI. The VEGF-A levels were negatively correlated with NIHSS but positively correlated with MMSE, FMA, and MBI. Conclusion: Both MDSS and conventional rehabilitation significantly reduce the production of IL-17A and TNF-α, increase the VEGF-A levels, and effectively improve cognition and motor function of hemiplegic patients with AIS, and the effects of MDSS and conventional rehabilitation are comparable.

Alleviation of ischemic brain injury by exercise preconditioning is associated with modulation of autophagy and mitochondrial dynamics in cerebral cortex of female aged mice.

Evidence from clinical studies and preclinical studies supports that exercise preconditioning can not only reduce the risk of stroke but also improve brain tissue and functional outcome after stroke. It has been demonstrated that autophagy and mitochondrial dynamics are involved in ischemic stroke. However, it is still unclear whether exercise preconditioning-induced neuroprotection against stroke is associated with modulation of autophagy and mitochondrial dynamics. Although age and sex interactively affect ischemic stroke risk, incidence, and outcome, studies based on young male animals are most often used to explore the role of exercise preconditioning in the prevention of ischemic stroke. In the current study, we examined whether exercise preconditioning could modulate autophagy and mitochondrial dynamics in a brain ischemia and reperfusion (I/R) model of female aged mice. The results showed that exercise preconditioning reduced infarct volume and improved neurological deficits. Additionally, increased levels of autophagy-related proteins LC3-II/LC3-I, LC3-II, p62, Atg7, and mitophagy-related proteins Bnip3L and Parkin, as well as increased levels of mitochondrial fusion modulator Mfn2 and mitochondrial fission modulator Drp1 in the ischemic cortex of female aged mice at 12 h after I/R were present. Our results could contribute to a better understanding of exercise preconditioning-induced neuroprotection against ischemic stroke for the elderly.

Hypotension and cognitive impairment among the elderly: Evidence from the CLHLS.

BACKGROUND: While high blood pressure has been linked to cognitive impairment, the relationship between low blood pressure, especially hypotension, and cognitive impairment has not been well studied. Therefore, this study aimed to assess the prevalence of hypotension and cognitive impairment in the seniors of China, and the association between hypotension and cognitive function impairment. METHODS: The data was derived from the 2018 wave of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Systolic blood pressures (SBP) and diastolic blood pressures (DBP) were measured by objective examination. The Chinese version of the Mini-Mental State Examination (CMMSE) was used to evaluate the cognitive impairment of the elderly. Generalized linear models were conducted to evaluate the association of hypotension with cognitive impairment. RESULTS: The prevalence of hypotension and cognitive impairment in the Chinese elderly were 0.76% and 22.06%, respectively. Participants with hypotension, lower SBP, and lower DBP, had odds ratios of 1.62, 1.38, and 1.48 for cognitive impairment, respectively. Besides, the CMMSE scores decreased by 2.08, 0.86, and 1.08 in the elderly with hypotension, lower SBP, and DBP, compared with those with non-hypotension, higher SBP, and DBP, respectively. Subgroup analyses showed that the association of cognitive impairment with hypotension was stronger in Chinese elderly who had decreased activity of daily living. Moreover, there was statistical evidence of a nonlinear dose-response relationship of SBP and DBP with cognitive impairment (Pnonlinear < 0.05). CONCLUSION: Hypotension was a potential risk factor for cognitive impairment of the Chinese elderly, especially for those having decreased activity of daily living. Blood pressure management should be conducted to prevent them from cognitive impairment.

Research on prognostic risk assessment model for acute ischemic stroke based on imaging and multidimensional data.

Accurately assessing the prognostic outcomes of patients with acute ischemic stroke and adjusting treatment plans in a timely manner for those with poor prognosis is crucial for intervening in modifiable risk factors. However, there is still controversy regarding the correlation between imaging-based predictions of complications in acute ischemic stroke. To address this, we developed a cross-modal attention module for integrating multidimensional data, including clinical information, imaging features, treatment plans, prognosis, and complications, to achieve complementary advantages. The fused features preserve magnetic resonance imaging (MRI) characteristics while supplementing clinical relevant information, providing a more comprehensive and informative basis for clinical diagnosis and treatment. The proposed framework based on multidimensional data for activity of daily living (ADL) scoring in patients with acute ischemic stroke demonstrates higher accuracy compared to other state-of-the-art network models, and ablation experiments confirm the effectiveness of each module in the framework.

Enhancing Neuroplasticity in the Chronic Phase After Stroke: Effects of a Soft Robotic Exosuit on Training Intensity and Brain-Derived Neurotrophic Factor.

Objective: High intensity training may enhance neuroplasticity after stroke; however, gait deficits limit the ability to achieve and sustain high walking training intensities. We hypothesize that soft robotic exosuits can facilitate speed-based gait training at higher intensities and longer durations, resulting in a corresponding increase in circulating brain-derived neurotrophic factor (BDNF). Results: Eleven individuals >6-mo post-stroke completed a two-session, pilot randomized crossover trial (NCT05138016). Maximum training speed (Δ: 0.07 ± 0.03 m/s), duration (Δ: 2.07 ± 0.88 min), and intensity (VO2 peak, Δ: 1.75 ± 0.60 ml-O2/kg/min) significantly increased (p < 0.05) during exosuit-augmented training compared to no-exosuit training. Post-session increases in BDNF (Δ: 5.96 ± 2.27 ng/ml, p = 0.03) were observed only after exosuit-augmented training. Biomechanical changes were not observed after exosuit-augmented training; however, a deterioration in gait propulsion symmetry (%Δ: -5 ± 2 %) and an increase in nonparetic propulsion (Δ: 0.9 ± 0.3 %bw) were observed (p < 0.05) after no-exosuit training. Conclusion: Soft robotic exosuits facilitate faster, longer duration, and higher intensity walking training associated with enhanced neuroplasticity.

Role of Articulatory Motor Networks in Perceptual Categorization of Speech Signals: A 7 T fMRI Study.

BACKGROUND: The association between brain regions involved in speech production and those that play a role in speech perception is not yet fully understood. We compared speech production related brain activity with activations resulting from perceptual categorization of syllables using high field 7 Tesla functional magnetic resonance imaging (fMRI) at 1-mm isotropic voxel resolution, enabling high localization accuracy compared to previous studies. METHODS: Blood oxygenation level dependent (BOLD) signals were obtained in 20 normal hearing subjects using a simultaneous multi-slice (SMS) 7T echo-planar imaging (EPI) acquisition with whole-head coverage and 1 mm isotropic resolution. In a speech production localizer task, subjects were asked to produce a silent lip-round vowel /u/ in response to the visual cue "U" or purse their lips when they saw the cue "P". In a phoneme discrimination task, subjects were presented with pairs of syllables, which were equiprobably identical or different along an 8-step continuum between the prototypic /ba/ and /da/ sounds. After the presentation of each stimulus pair, the subjects were asked to indicate whether the two syllables they heard were identical or different by pressing one of two buttons. In a phoneme classification task, the subjects heard only one syllable and asked to indicate whether it was /ba/ or /da/. RESULTS: Univariate fMRI analyses using a parametric modulation approach suggested that left motor, premotor, and frontal cortex BOLD activations correlate with phoneme category variability in the /ba/-/da/ discrimination task. In contrast, the variability related to acoustic features of the phonemes were the highest in the right primary auditory cortex. Our multivariate pattern analysis (MVPA) suggested that left precentral/inferior frontal cortex areas, which were associated with speech production according to the localizer task, play a role also in perceptual categorization of the syllables. CONCLUSIONS: The results support the hypothesis that articulatory motor networks in the left hemisphere that are activated during speech production could also have a role in perceptual categorization of syllables. Importantly, high voxel-resolution combined with advanced coil technology allowed us to pinpoint the exact brain regions involved in both perception and production tasks.

Inhibition of Rho-kinase attenuates endothelial-leukocyte interaction during ischemia-reperfusion injury.

Resuscitation from hemorrhagic shock induces endothelial dysfunction and activates inflammatory cascades leading to organ damage. Following restoration of blood flow to ischemic vascular beds, leukocyte-endothelium interactions leading to leukocyte infiltration into the vascular wall occur very early due, in part, to the loss of endothelium-derived nitric oxide (NO). The mechanism by which ischemia-reperfusion injury impairs endothelium-derived NO is not completely understood. We hypothesized that inhibition of Rho-kinase could exert beneficial effects following hemorrhagic shock by preserving endothelial function and attenuating leukocyte trafficking in the microcirculation. Using intravital microscopy, we found that resuscitation from hemorrhage acutely increased the number of rolling and adherent leukocytes in the mouse splanchnic microcirculation. Treatment of mice with the Rho-kinase inhibitor fasudil, markedly attenuated leukocyte-endothelium interaction in response to hemorrhage/reinfusion. The beneficial effect of fasudil was not observed in endothelial nitric oxide synthase (eNOS)(-/-) mice. In conclusion, inhibition of Rho-kinase prevents inflammatory leukocyte trafficking in the microcirculation via an eNOS-dependent mechanism. Our data support a role for Rho-kinase inhibitors in the treatment of ischemia-reperfusion injury.

Distributions, sources, and backward trajectories of atmospheric polycyclic aromatic hydrocarbons at Lake Small Baiyangdian, Northern China.

Air samples were collected seasonally at Lake Small Baiyangdian, a shallow lake in northern China, between October 2007 and September 2008. Gas phase, particulate phase and dust fall concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured using a gas chromatograph-mass spectrometer (GC-MS). The distribution and partitioning of atmospheric PAHs were studied, and the major sources were identified; the backward trajectories of air masses starting from the center of Lake Small Baiyangdian were calculated for the entire year. The following results were obtained: (1) The total concentration of 16 priority controlled PAHs (PAH16) in the gas phase was 417.2 ± 299.8 ng · m(-3), in the particulate phase was 150.9 ± 99.2 ng · m(-3), and in dust fall was 6930.2 ± 3206.5 ng · g(-1). (2) Vehicle emission, coal combustion, and biomass combustion were the major sources in the Small Baiyangdian atmosphere and accounted for 28.9%, 45.1% and 26.0% of the total PAHs, respectively. (3) Winter was dominated by relatively greater PAHs polluted northwesterly air mass pathways. Summer showed a dominant relatively clean southern pathway, whereas the trajectories in autumn and spring might be associated with high pollution from Shanxi or Henan province.

Levels, temporal-spatial variations, and sources of organochlorine pesticides in ambient air of Lake Chaohu, China.

The residual levels of OCPs in the gas phase and particle phase in Lake Chaohu, China, were measured using GC-MS from March 2010 to February 2011. The temporal-spatial variations and sources of OCPs were also analyzed. Twenty types of OCPs were detected in the gas phase with a total concentration of 484.8 ± 550.4 pg/m³. Endosulfan, DDTs and chlordane were the primary OCPs in the gas phase. The mean concentration of OCPs in the gas phase was significantly higher in the summer than in the winter. Seventeen types of OCPs were detected in the particle phase with a total concentration of 18.3 ± 26.1 pg/m³. DDTs were major OCPs in the particle phase. The mean concentration of OCPs in the particle phase decreased at first and then increased during the period. The potential source of the HCHs in ambient air of Lake Chaohu might come from recent lindane usage. DDTs mainly came from historical dicofol usage, and an input of DDT was observed in the spring, which may result from the present use of marine paint that contains technical DDT. Endosulfan and chlordane in the air may be due to the present use of technical endosulfan and chlordane.