Association of Calf Circumference, Hand Grip Strength, and Physical Performance with Serious Adverse Events in Patients with Sub-Acute Stroke Hospitalized for Rehabilitation: An Observational Study.

OBJECTIVE: To determine whether calf circumference (CC), hand grip strength (HGS), and physical performance are linked to the incidence of serious adverse events (SAEs) in patients with sub-acute stroke. DESIGN: Retrospective cohort study. SETTING: Single rehabilitation hospital. PARTICIPANTS: Stroke patients admitted for rehabilitation hospital. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: The incidence of SAEs, such as death, cardiovascular events including recurrent stroke, and conditions requiring transfer to another hospital for specialized care or immediate treatment for an acute illness during hospitalization. RESULTS: A total of 341 patients (median age: 74 years) participated in this study, with 232 patients (68%) exhibiting low physical performance. In the adjusted model, low physical performance was significantly associated with SAEs (HR = 3.01, 95% CI = 1.04-8.68, p = 0.042). However, low CC (HR = 1.60, 95% CI = 0.76-3.38, p = 0.219) and low HGS (HR = 0.98, 95% CI = 0.39-2.42, p = 0.960) did not show an independent association. CONCLUSION: Low physical performance was independently associated with the occurrence of SAEs during hospitalization for rehabilitation in patients with sub-acute stroke.

Muscle weakness is more strongly associated with functional outcomes in patients with stroke than sarcopenia or muscle wasting: an observational study.

BACKGROUND: Stroke-related sarcopenia is an important prognosis factor and an intervention target for improving outcomes in patients with stroke. AIM: This study aimed to identify the association between sarcopenia, possible sarcopenia, muscle weakness, muscle mass and calf circumference, and the functional outcomes 3 months after stroke. METHODS: In this single-centre prospective observational study, muscle strength, muscle mass, and calf circumference were measured in patients with acute stroke at hospital discharge. Diagnosis of sarcopenia, possible sarcopenia, muscle weakness, low muscle mass, and low calf circumference were defined according to the 2019 Asian Working Group for Sarcopenia criteria. The primary outcome measure was the modified Rankin Scale (mRS) score at 3 months, with an mRS score of 3 or higher indicating a poor outcome. Logistic regression analysis was conducted to examine independent associations between each assessment and functional outcomes. RESULTS: A total of 247 patients (median age: 73 years) were included in this study. The prevalence of sarcopenia was 28% (n = 70), and in the adjusted model, sarcopenia (aOR = 2.60, 95% CI 1.07-6.31, p = 0.034), muscle weakness (aOR = 3.40, 95% CI 1.36-8.52, p = 0.009), and low muscle mass (aOR = 2.61, 95% CI 1.04-6.52) were significantly associated with poor functional outcome. Nevertheless, other evaluations did not demonstrate an independent association with the outcome. CONCLUSION: Sarcopenia, muscle weakness, and low muscle mass were found to be independently associated with functional outcomes 3 months after stroke, and muscle weakness exhibited the strongest association with outcomes among them.

Association of Malnutrition With Physical Activity Intensity in Patients With Subacute Stroke.

OBJECTIVE: To investigate the relationship between nutritional status measured by the Global Leadership Initiative on Malnutrition (GLIM) criteria and the intensity of physical activity, and to determine the association between these factors and the activities of daily living (ADLs) in patients with subacute stroke during hospitalization. DESIGN: A cross-sectional study. SETTING: The study was conducted in the rehabilitation unit at a neurosurgical hospital. PARTICIPANTS: One hundred and twenty-eight patients with subacute stroke (N=128). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Nutritional status was assessed using GLIM criteria. Sedentary behavior (SB), light-intensity physical activity (LIPA), and moderate-to-vigorous physical activity (MVPA) were measured using an accelerometer. Multiple regression analysis was used to investigate the relationship between nutritional status and intensity of physical activity. Moreover, the association of nutritional status and physical activity intensity with ADLs was determined using multiple regression analysis and mediation analysis. RESULTS: Malnutrition was associated with SB time (B = 16.241, P=.009) and LIPA time (B = -17.656, P=.002), but not MVPA time (B = -0.472, P=.776). SB time (B = -0.063, P=.009) and LIPA time (B = 0.093, P<.001) were associated with functional independence measure for motor function, while MVPA time (B = -0.080, P=.379) was not. SB time (coefficient = -10.785, P<.001) and LIPA time (coefficient = -12.054, P<.001) were significant mediators between nutrition status and ADLs. CONCLUSIONS: Malnutrition was associated with a SB time and LIPA time, but not MVPA time, in patients with sub-acute stroke. SB and LIPA times were associated with ADLs and mediated between nutrition status and ADLs in these patients. The association of nutritional status on physical activity and ADLs should be considered in stroke rehabilitation.

Care-needs Certification in the National Long-Term Care Insurance is Useful for Assessment of Premorbid Function in Older Japanese Patients with Stroke.

OBJECTIVE: To investigate the effects of premorbid long-term care insurance (LTCI) care-need certification on functional improvement during acute hospitalization in older patients with stroke. METHODS: In this single-center prospective cohort study, we assessed LTCI care-needs certification and the modified Rankin Scale (mRS) at the premorbid stage, on admission, and at hospital discharge in older patients with stroke. We also assessed adverse events during hospitalization. The main outcome was the presence of functional improvement during hospitalization (mRS on admission < mRS at discharge). Multivariate analysis was performed to investigate the relationship between functional improvement and premorbid LTCI care-need certification. RESULTS: In total, 246 older patients with stroke were enrolled in this study. There was a significant independent association between premorbid LTCI care-needs certification (care level 1 = odds ratio [OR]: 0.26, 95% CI: 0.10-0.72, p = 0.01; Care level 2 = OR: 0.27, 95% CI: 0.10-0.73, p = 0.01; care level 3-5 = OR: 0.21, 95% CI: 0.08-0.56, p = 0.002; Not applicable = reference) and functional improvement. CONCLUSIONS: Premorbid LTCI care-need certification is associated with short-term functional improvement in older patients with stroke. Assessment of premorbid LTCI care-needs certification is valid for predicting functional improvement in older patients with stroke.

Quantitative Difference in Solubility of Diastereomeric (2H/1H)-Isotopomers.

Many achiral organic compounds become chiral by an isotopic substitution of one of the enantiotopic moieties in their structures. Although spectroscopic methods can recognize the molecular chirality due to an isotopic substitution, the effects of isotopically chiral compounds in enantioselective reactions have remained unsolved because the small chirality arises only from the difference between the number of neutrons in the atomic nuclei. The difference between the diastereomeric isotopomers of reactive sources should be the key to these effects. However, the energy difference between them is difficult to calculate, even using present computational methods, and differences in physical properties have not yet been reported. Here, we demonstrate that the small energy difference between the diastereomeric isotopomers at the molecular level can be enhanced to appear as a solubility difference between the diastereomeric (2H/1H) isotopomers of α-aminonitriles, synthesized from an isotopically chiral amine, achiral aldehyde, and HCN. This small, but measurable, difference induces the chiral (d/l) imbalance in the suspended α-aminonitrile; therefore, a second enhancement in the solid-state chirality proceeds to afford a highly stereoimproved aminonitrile (>99% selectivity) whose handedness arises completely from the excess enantiomer of isotopically chiral amine, even in a low enantiomeric excess and low deuterium-labeling ratio. Because α-aminonitriles can be hydrolyzed to chiral α-amino acids with the removal of an isotope-labeling moiety, the current sequence of reactions represents a highly enantioselective Strecker amino acid synthesis induced by the chiral hydrogen (2H/1H) isotopomer. Thus, hydrogen isotopic chirality links directly with the homochirality of α-amino acids via a double enhancement of α-aminonitrile, the chiral intermediate of a proposed prebiotic mechanism.

Prevalence of Malnutrition Diagnosed with GLIM Criteria and Association with Activities of Daily Living in Patients with Acute Stroke.

BACKGROUND: Malnutrition is associated with a poor functional outcome in patients with stroke. However, the prevalence of malnutrition diagnosed with the Global Leadership Initiative on Malnutrition (GLIM) criteria or its association with activity of daily living (ADL) in patients with acute stroke have not been reported. OBJECTIVE: To investigate the prevalence of the malnutrition diagnosed with the GLIM criteria and its association with ADL or discharge destination in patients with acute stroke. MATERIALS AND METHODS: In this cross-sectional study, we diagnosed malnutrition with the GLIM criteria and the European Society for Clinical Nutrition and Metabolism (ESPEN) criteria and assessed ADL by functional independence measure motor domain (FIM-M) score in patients with acute stroke. Multivariate regression analysis was used to investigate the relationship between FIM-M score or home discharge and malnutrition defined with GLIM or ESPEN criteria. RESULTS: A total of 115 acute stroke patients (39 females; median age: 72 years) were enrolled in this study. The prevalence of malnutrition according to GLIM-criteria and ESPEN-criteria was 28.7% and 16.5%, respectively. Multivariate analyses for FIM-M score after adjusting for potential confounders showed that GLIM criteria and ESPEN criteria were independently associated with FIM-M score (ß = -0.238, p < 0.001; ß = -0118, p = 0.040, respectively). A multivariate analysis for discharge destination found that only malnutrition from the GLIM criteria was significantly associated with home discharge (OR = 0.08, 95% confidential interval = 0.01-0.69, p = 0.02). CONCLUSIONS: Malnutrition with the GLIM criteria is negatively associated with ADL and is also associated with discharge destination in patients with acute stroke.

Crystal structure of chalcone synthase, a key enzyme for isoflavonoid biosynthesis in soybean.

Isoflavonoid is one of the groups of flavonoids that play pivotal roles in the survival of land plants. Chalcone synthase (CHS), the first enzyme of the isoflavonoid biosynthetic pathway, catalyzes the formation of a common isoflavonoid precursor. We have previously reported that an isozyme of soybean CHS (termed GmCHS1) is a key component of the isoflavonoid metabolon, a protein complex to enhance efficiency of isoflavonoid production. Here, we determined the crystal structure of GmCHS1 as a first step of understanding the metabolon structure, as well as to better understand the catalytic mechanism of GmCHS1.

Pre-Stroke Frailty and Stroke Severity in Elderly Patients with Acute Stroke.

OBJECTIVE: Frailty is a major problem in super-aged societies. Because frailty assessments are largely unstudied in acute stroke settings, few reports have evaluated the association between pre-stroke frailty and stroke severity. The aim of this study was to determine the association between pre-stroke frailty and stroke severity in elderly patients with acute stroke. MATERIALS AND METHODS: This cross-sectional study enrolled consecutive elderly patients with acute stroke. We assessed stroke severity with the National Institutes of Stroke Scale (NIHSS), and pre-stroke frailty with a Frailty Screening Index in elderly patients with acute stroke. Patients were divided according to their Frailty Screening Index: the robust group, pre-frailty group, and frailty group. Multiple linear regression analysis was used to determine whether pre-stroke frailty was independently associated with NIHSS score. RESULTS: In total, 234 elderly patients with acute stroke (age: 75.7 years; 149 men, 85 women) were enrolled in this study. Of these, the robust group comprised 76 patients, the pre-frailty group comprised 129 patients, and the frailty group comprised 29 patients. The prevalence of pre-stroke frailty was 12.4%. Multiple linear regression analysis showed that pre-stroke pre-frailty and frailty were significantly associated with NIHSS score (pre-frailty; ß = 1.191, P = .005, frailty; ß = 1.708, P = .009). CONCLUSIONS: The present study indicated that the pre-stroke frailty was significantly associated with stroke severity in elderly patients with acute stroke. Additional study is needed to clarify the association between pre-stroke frailty and post-stroke prognosis.

Association of fear of falling with acceleration-derived gait indices in older adults with knee osteoarthritis.

BACKGROUND: Knee osteoarthritis (OA) and fear of falling (FoF) are important factors contributing to trunk oscillation during walking. It is of a clinical importance to clarify the association of FoF with trunk oscillation during walking in older adults with knee OA (knee OA adults). AIM: The purpose of this study was to investigate the association of FoF with trunk oscillation during walking in knee OA adults. METHODS: Forty-one patients who met the criteria participated in the study and were classified into two groups based on their answer to a question on FoF. An accelerometer was attached at the level of the third lumbar vertebra (L3) and the seventh cervical vertebra (C7), and the accelerations at L3 and C7 were measured during a 10-m gait test. Using these data, the acceleration-derived gait indices, such as stride time variability (STV), root mean square (RMS), and autocorrelation at the trunk in the anteroposterior (AP) and mediolateral (ML) directions, were computed. RESULTS: FoF was associated with a higher STV value and a smaller RMS value in the ML direction at L3. DISCUSSION: The decreased trunk oscillation in the ML direction in knee OA adults with FoF may reflect a positive, compensatory adaptation for trunk control. CONCLUSION: Knee OA adults with FoF decreased trunk oscillation during walking than those without FoF.

Prestroke Sarcopenia and Stroke Severity in Elderly Patients with Acute Stroke.

OBJECTIVE: The association between prestroke sarcopenia and stroke severity has not been evaluated previously. The purpose of this study was to determine whether prestroke sarcopenia is associated with stroke severity in elderly patients with acute stroke. METHODS: We assessed prestroke sarcopenia of elderly patients with acute stroke by using a questionnaire for sarcopenia (SARC-F). Patients were divided into groups according to their SARC-F score: SARC-F score less than 4 (nonsarcopenia) and SARC-F score ≥4 (prestroke sarcopenia). Stroke severity was assessed according to the National Institute of Health Stroke Scale. Logistic regression was used to derive crude and adjusted odds ratio for the presence of prestroke sarcopenia and stroke severity. RESULTS: Among the 183 patients enrolled (age, median [interquartile range]: 75 [11] years; 103 men), the prevalence of prestroke sarcopenia was 15% (n = 27). Crude odds ratio for the presence of prestroke sarcopenia and moderate-to-severe stroke (National Institute of Health Stroke Scale score > 5) was 4.00 (95% confidence interval, 1.68-9.53; P = .002). After adjusting for confounding variables (age, sex, and stroke risk factors), the presence of prestroke sarcopenia remained an independent predictor of severe stroke, with an odds ratio of 3.54 (95% confidence interval, 1.32-9.49; P= .01). CONCLUSIONS: Prestroke sarcopenia can predict moderate to severe stroke in elderly patients with acute stroke.

Long-Term Effect of Promoting In-Hospital Physical Activity on Postdischarge Patients with Mild Ischemic Stroke.

BACKGROUND: Although there are reports on the promotion of physical activity during hospitalization, there is no evidence that promoting in-hospital physical activity continues over time after discharge. The purpose of this study was to evaluate the long-term effect of promoting in-hospital physical activity on postdischarge physical activity and self-efficacy for physical activity in patients with mild ischemic stroke. METHODS: This was a cross-sectional study of a post hoc analysis of a previous randomized controlled trial. Patients with mild ischemic stroke were divided into the intervention group (in which physical activity was promoted during hospitalization) and a control group. To promote in-hospital physical activity, patients in the intervention group were instructed in the self-monitoring approach. After discharge, we measured physical activity and self-efficacy for physical activity by mailing a questionnaire to the patients. The average number of steps taken was used the index of postdischarge physical activity. RESULTS: The study sample comprised 30 patients, with 13 patients in the intervention group and 17 patients in the control group. There were no significant differences in physical activity values (6176.8 versus 6112.8 steps/day, P = .932) and self-efficacy for physical activity score (66.0 versus 76.0 points, P = .801) between the 2 groups. CONCLUSIONS: This study showed that the promotion of in-hospital physical activity did not appear to increase physical activity and self-efficacy for physical activity in patients with mild ischemic stroke after discharge. Additional study is needed to establish a more specific approach to promote physical activity during hospitalization that will carry over during long-term follow-up.

Heart Rate Variability During Early Mobilization in Patients with Acute Ischemic Stroke.

Autonomic dysfunction is one of the predictors of poor outcome in patients with acute ischemic stroke. We compared the heart rate variability (HRV) during early mobilization in patients with or without neurological deterioration (ND). We enrolled 7 acute ischemic patients with ND and 14 without ND and measured their HRV in the rest and mobilization by electrocardiography. There was a significant difference in sympathetic nervous activity during mobilization between the 2 groups. However, no significant differences in blood pressure, heart rate, and parasympathetic nerve activity were observed. In patients with acute ischemic stroke, it is likely that the increase in sympathetic nervous activity during mobilization is associated with ND.

Physical Activity, Physical Function, and Quadriceps Muscle Thickness in Male Patients with Sub-Acute Stroke during Hospitalization: A Pilot Study.

Increasing physical activity (PA) is an important rehabilitation target for patients with sub-acute stroke during hospitalization in order to recover physical function and prevent stroke recurrence. However, the characteristics of low PA in stroke patients during hospitalization who were targets for increased intervention have not been reported. The purpose of this study was to investigate the relationship between the daily number of steps and physical function and quadriceps muscle thickness (QMT) in patients with sub-acute stroke during hospitalization for convalescence rehabilitation. Twenty-nine patients with ischemic or haemorrhagic stroke (mean age, 69 ± 11 years) hospitalized for inpatient convalescent rehabilitation were included. PA was measured using a three-dimensional accelerometer that calculates the daily number of steps taken. Physical function was measured by a short physical performance battery (SPPB; 0-12 points) and the leg motor selectivity score (6 motor stages defined by Brunnstrom), and the QMT of both legs was measured using ultrasonography. PA was significantly correlated with the SPPB score (r = 0.63, p = 0.0002), QMT on the paretic side (r = 0.41, p = 0.02), and QMT on non-paretic side (r = 0.56, p = 0.002). There were no significant effects of the leg motor selectivity score on daily PA (F = 1.37, p = 0.27). In the multiple regression analysis, only the SPPB score showed significant linear regression (ß = 0.44, p = 0.02). PA in male patients with sub-acute stroke during hospitalization was related to physical function and QMT and not with the severity of paresis.

Effect of accelerometer-based feedback on physical activity in hospitalized patients with ischemic stroke: a randomized controlled trial.

OBJECTIVE: To evaluate the effect of accelerometer-based feedback on physical activity in hospitalized patients with ischemic stroke. DESIGN: Randomized controlled trial. SETTING: Acute care hospital. SUBJECTS: A total of 55 patients with ischemic stroke who could walk without assistance were randomly assigned to the intervention group ( n = 27) or the control group ( n = 28). INTERVENTIONS: At the baseline measurement, patients did not receive accelerometer-based feedback. At follow-up, a physical therapist provided instruction on accelerometer-based feedback, discussed physical activity targets and encouraged the patients to walk more until discharge. MAIN MEASURES: The average daily number of steps taken was used as the index of daily hospitalized physical activity. RESULTS: The study sample consisted of 48 patients, of whom 23 patients comprised the intervention group and 25 patients comprised the control group. Although there were no significant differences in physical activity values between the two groups at the baseline measurement, the values in the intervention group at follow-up were significantly higher than those in the control group (5180.5 ± 2314.9 vs. 3113.6 ± 1150.9 steps/day, P = 0.0003). The effect size of physical activity values (Cohen's d = 1.15) at follow-up was large between the two groups. CONCLUSION: Exercise training combined with accelerometer-based feedback effectively increased physical activity in hospitalized patients with ischemic stroke.

Safety and Feasibility of the 6-Minute Walk Test in Patients with Acute Stroke.

BACKGROUND: Our objective was to investigate the safety and feasibility of the 6-minute walk test in patients with acute stroke. MATERIALS AND METHODS: Consecutive patients with acute stroke, admitted to the Itami Kosei Neurosurgical Hospital from September 2016 to April 2017 were enrolled. Walking capacity was assessed by a physical therapist using the 6-minute walk test in 94 patients with acute stroke within 14 days of hospital admission. The primary outcomes were safety (i.e., the prevalence of new adverse events during and after the test) and feasibility (i.e., test completion rate) of the 6-minute walk test. RESULTS: The 6-minute walk test was performed for a mean duration of 5.1 days (standard deviation, 2.6 days) after hospital admission. Seventy patients (74.5%) could walk without standby assistance or a walking aid, and 24 patients (25.5%) could walk without standby assistance but with a walking aid. The average distance walked by patients during the 6-minute walk test was 331 m (standard deviation, 107.2 m). Adverse events following the 6-minute walk test occurred in 6 patients (6.4%) and included stroke progression, stroke recurrence, seizures, and neurological deterioration. Heart rate increase (>120 beats/min) occurred in 3 patients (3.2%) during the test. Lastly, 6 patients (6.4%) were unable to complete the 6-minute walk test. CONCLUSIONS: Although performance in the 6-minute walk test was decreased in patients with acute stroke, the test itself appears to be safe and feasible in this patient population.

Validity of Quadriceps Muscle Thickness Measurement in Patients with Subacute Stroke during Hospitalization for Assessment of Muscle Wasting and Physical Function.

BACKGROUND: Many patients with stroke have difficulty performing voluntary muscle contraction; thus, measurement of patients' muscle power or leg strength is challenging. We investigated the validity of quadriceps muscle thickness (QMT) measurement using ultrasonography (US) for the assessment of muscle wasting and physical function in patients with subacute stroke during hospitalization for convalescent rehabilitation. METHODS: Participants included 52 men with ischemic or hemorrhagic stroke (mean age, 69 ± 11 years) who were hospitalized for inpatient convalescent rehabilitation. The QMT of both legs was measured using US, and functional outcome was assessed according to the modified Rankin Scale (mRS) score and the leg motor selectivity score (6 motor stages defined by Brunnstrom). RESULTS: There was a significant correlation between QMT and leg motor selectivity score (paretic limb: r = .60, P < .001; nonparetic limb: r = .54, P < .001). Additionally, there were significant interaction effects between the QMT of the paretic limb (mRS scores = 1 or 2, 3, 4, and 5 = 3.52 ± .84 cm, 3.19 ± .52 cm, 2.50 ± .46 cm, and 2.20 ± .71 cm, respectively; F = 11.2; P < .0001), the QMT of the nonparetic limb (mRS scores = 1 or 2, 3, 4, and 5 = 3.72 ± .82 cm, 3.16 ± .49 cm, 2.91 ± .54 cm, and 2.42 ± .82 cm, respectively; F = 8.3; P < .001), and functional outcome. CONCLUSION: QMT measurement is a valid method to assess muscle wasting and physical function in patients with subacute stroke during hospitalization for convalescent rehabilitation.

Crystal Structure of the 11-cis Isomer of Pharaonis Halorhodopsin: Structural Constraints on Interconversions among Different Isomeric States.

Like other microbial rhodopsins, the light driven chloride pump halorhodopsin from Natronomonas pharaonis (pHR) contains a mixture of all-trans/15-anti and 13-cis/15-syn isomers in the dark adapted state. A recent crystallographic study of the reaction states of pHR has shown that reaction states with 13-cis/15-syn retinal occur in the anion pumping cycle that is initiated by excitation of the all-trans isomer. In this study, we investigated interconversions among different isomeric states of pHR in the absence of chloride ions. The illumination of chloride free pHR with red light caused a large blue shift in the absorption maximum of the retinal visible band. During this "red adaptation", the content of the 11-cis isomer increased significantly, while the molar ratio of the 13-cis isomer to the all-trans isomer remained unchanged. The results suggest that the thermally activated interconversion between the 13-cis and the all-trans isomers is very rapid. Diffraction data from red adapted crystals showed that accommodation of the retinal chromophore with the 11-cis/15-syn configuration was achieved without a large change in the retinal binding pocket. The measurement of absorption kinetics under illumination showed that the 11-cis isomer, with a λmax at 565 nm, was generated upon excitation of a red-shifted species (λmax = 625 nm) that was present as a minor component in the dark adapted state. It is possible that this red-shifted species mimics an O-like reaction state with 13-cis/15-syn retinal, which was hypothesized to occur at a late stage of the anion pumping cycle.

Changes in quadriceps muscle thickness in acute non-ambulatory stroke survivors.

BACKGROUND: Loss of skeletal muscle mass is one of the main reasons for disability in patients with stroke. However, lower leg muscle wasting has not been studied in acute stroke patients. OBJECTIVE: To investigate the changes in quadriceps muscle thickness in acute non-ambulatory stroke survivors. METHODS: A total of 16 consecutive acute non-ambulatory stroke survivors who were in acute inpatient rehabilitation, with a mean age of 72.1 years, were included in the study. Quadriceps muscle thickness was examined in their paretic and non-paretic limbs within the first week from admission (first week), 1 week after the first examination (second week), and 1 week after the second week examination (third week) using ultrasonography. RESULTS: Quadriceps muscle thickness in the paretic limb decreased every week (mean% difference between the first and second weeks, 12.8, 95% confidence interval (CI) 5.3-20.2%; mean% difference between the second and third weeks, 10.1, 95% CI 5.2-14.9%). Quadriceps muscle thickness in the non-paretic limb was lower in the second and third weeks than the first week, but there was no difference between the second and third weeks (mean% difference between the first and second weeks, 9.3, 95% CI 2.5-16.1%; mean% difference between the second and third weeks, 5.3, 95% CI - 1.6 to 12.1%). CONCLUSION: Quadriceps muscle thickness decreased in acute non-ambulatory stroke survivors not only in the paretic limb but also in the non-paretic limb, particularly during the period from admission to the second week.

Changes in Quadriceps Muscle Thickness, Disease Severity, Nutritional Status, and C-Reactive Protein after Acute Stroke.

BACKGROUND: Lower leg muscle wasting is common in stroke patients; however, patient characteristics in the acute phase are rarely studied. This study aimed to examine the relationship between changes in quadriceps muscle thickness and disease severity, nutritional status, and C-reactive protein (CRP) levels after acute stroke. METHODS: Thirty-one consecutive patients with acute intracerebral hemorrhage or ischemic stroke had quadriceps muscle thickness measured in the paretic and nonparetic limbs within 1 week after admission (first week) and 2 weeks after the first examination (last week) using ultrasonography. We also determined the relationship between the percentage change in muscle thickness and disease severity, nutritional status, and CRP levels on admission. RESULTS: There was a significant correlation between changes in muscle thickness for both paretic and nonparetic sides and National Institutes of Health Stroke Scale (NIHSS) scores (paretic limb: r = -.46, P = .01; nonparetic limb: r = -.54, P = .002, respectively); however, there was no significant correlation with nutritional status on admission. Quadriceps muscle thickness was reduced more in the CRP-positive (≥.3 mg/dL) patients than in the CRP-negative (<.3 mg/dL) patients in the nonparetic limb (positive: -21.4 ± 12.1, negative: -11.4 ± 16.4%; P = .039), but not in the paretic limb (positive: -23.4 ± 9.0, negative: -19.1 ± 15.7; P = .27). CONCLUSIONS: A high NIHSS score and a positive CRP on admission were both significantly correlated with decreased quadriceps muscle thickness after acute stroke. Nutritional status on admission was not correlated with changes in quadriceps muscle thickness for these patients.

Crystal structures of the L1, L2, N, and O states of pharaonis halorhodopsin.

Halorhodopsin from Natronomonas pharaonis (pHR) functions as a light-driven halide ion pump. In the presence of halide ions, the photochemical reaction of pHR is described by the scheme: K→ L1 → L2 → N → O → pHR' → pHR. Here, we report light-induced structural changes of the pHR-bromide complex observed in the C2 crystal. In the L1-to-L2 transition, the bromide ion that initially exists in the extracellular vicinity of retinal moves across the retinal Schiff base. Upon the formation of the N state with a bromide ion bound to the cytoplasmic vicinity of the retinal Schiff base, the cytoplasmic half of helix F moves outward to create a water channel in the cytoplasmic interhelical space, whereas the extracellular half of helix C moves inward. During the transition from N to an N-like reaction state with retinal assuming the 13-cis/15-syn configuration, the translocated bromide ion is released into the cytoplasmic medium. Subsequently, helix F relaxes into its original conformation, generating the O state. Anion uptake from the extracellular side occurs when helix C relaxes into its original conformation. These structural data provide insight into the structural basis of unidirectional anion transport.