Effects of D-Allulose with Sucrose Beverage on Glucose Tolerance and Insulin Levels among Thai Healthy Volunteers.

D-Allulose has blood glucose suppression effects in both animal and clinical studies. The mechanism mediating glucose suppression in animals is controlled by several actions including the inhibition of sucrase. To investigate the dose-response effects of D-allulose with a sucrose beverage on glucose tolerance and insulin levels using Thai volunteers. This was a prospective, randomized, double-blinded, crossover study. Subjects had five oral sucrose tolerance tests (OSTT) with escalating doses of D-allulose (0, 2.5, 5, 7.5 or 10 g) with a 50 g sucrose beverage in a random order once a week for five consecutive weeks. The five drinks were consumed in a random order; the order being blinded for both subjects and investigators. Blood samples were drawn immediately before consumption and at 30, 60, 90 and 120 min after consumption of the study product for measurement of plasma glucose and insulin levels. Thirty healthy subjects (11 men and 19 women) completed the study. The peak postprandial glucose (PePPG) and insulin levels (PePPI) were lower when D-allulose was added in a dose-dependent manner. The lowest plasma glucose and insulin levels occurred at 120 min after OSTT in all five products and they were raised when D-allulose was added in a dose-dependent manner. D-Allulose has a suppression response on glucose and insulin shown by the decrease in postprandial plasma glucose and insulin levels following the addition of D-allulose to sucrose in a dose-dependent manner. The more D-allulose added, the less marked the glucose and insulin response occurred.

Flat-panel Detector Perfusion Imaging and Conventional Multidetector Perfusion Imaging in Patients with Acute Ischemic Stroke : A Comparative Study.

PURPOSE: Flat-panel detector computed tomography (FDCT) is increasingly used in (neuro)interventional angiography suites. This study aimed to compare FDCT perfusion (FDCTP) with conventional multidetector computed tomography perfusion (MDCTP) in patients with acute ischemic stroke. METHODS: In this study, 19 patients with large vessel occlusion in the anterior circulation who had undergone mechanical thrombectomy, baseline MDCTP and pre-interventional FDCTP were included. Hypoperfused tissue volumes were manually segmented on time to maximum (Tmax) and time to peak (TTP) maps based on the maximum visible extent. Absolute and relative thresholds were applied to the maximum visible extent on Tmax and relative cerebral blood flow (rCBF) maps to delineate penumbra volumes and volumes with a high likelihood of irreversible infarcted tissue ("core"). Standard comparative metrics were used to evaluate the performance of FDCTP. RESULTS: Strong correlations and robust agreement were found between manually segmented volumes on MDCTP and FDCTP Tmax maps (r = 0.85, 95% CI 0.65-0.94, p < 0.001; ICC = 0.85, 95% CI 0.69-0.94) and TTP maps (r = 0.91, 95% CI 0.78-0.97, p < 0.001; ICC = 0.90, 95% CI 0.78-0.96); however, direct quantitative comparisons using thresholding showed lower correlations and weaker agreement (MDCTP versus FDCTP Tmax 6 s: r = 0.35, 95% CI -0.13-0.69, p = 0.15; ICC = 0.32, 95% CI 0.07-0.75). Normalization techniques improved results for Tmax maps (r = 0.78, 95% CI 0.50-0.91, p < 0.001; ICC = 0.77, 95% CI 0.55-0.91). Bland-Altman analyses indicated a slight systematic underestimation of FDCTP Tmax maximum visible extent volumes and slight overestimation of FDCTP TTP maximum visible extent volumes compared to MDCTP. CONCLUSION: FDCTP and MDCTP provide qualitatively comparable volumetric results on Tmax and TTP maps; however, direct quantitative measurements of infarct core and hypoperfused tissue volumes showed lower correlations and agreement.

Unique Neural Mechanisms Underlying Speed Control of Low-Force Ballistic Contractions.

According to the speed-control hypothesis, the rate of force development (RFD) during ballistic contractions is dictated by force amplitude because time to peak force (TPF) remains constant regardless of changes in force amplitude. However, this hypothesis has not been tested at force levels below 20% of an individual's maximum voluntary contraction (MVC). Here, we examined the relationship between the RFD and force amplitude from 2 to 85% MVC and the underlying structure of muscle activity in 18 young adults. Participants exerted ballistic index finger abductions for 50 trials in each of seven randomly assigned force levels (2, 5, 15, 30, 50, 70, and 85% MVC). We quantified TPF, RFD, and various EMG burst characteristics. Contrary to the speed-control hypothesis, we found that TPF was not constant, but significantly varied from 2 to 85% MVC. Specifically, the RFD slope from 2 to 15% MVC was greater than the RFD slope from 30 to 85% MVC. Longer TPF at low force levels was associated with the variability of EMG burst duration, whereas longer TPF with higher force levels was associated with the EMG burst integral. Contrary to the speed-control hypothesis, we found that the regulation of TPF for low and high force levels was different, suggesting that neuronal variability is critical for force levels below 30% MVC and neuronal amplitude for force levels above 30% MVC. These findings present compelling new evidence highlighting the limitations of the speed-control hypothesis underscoring the need for a new theoretical framework.

Linear and Nonlinear Behaviors of the Photoreceptor Coupled Network.

Photoreceptors are electrically coupled to one another, and the spatiotemporal properties of electrical synapses in a two-dimensional retinal network are still not well studied, because of the limitation of the single electrode or pair recording techniques which do not allow simultaneously measuring responses of multiple photoreceptors at various locations in the retina. A multiple electrode recording system is needed. In this study, we investigate the network properties of the two-dimensional rod coupled array of the salamander retina (both sexes were used) by using the newly available multiple patch electrode system that allows simultaneous recordings from up to eight cells and to determine the electrical connectivity among multiple rods. We found direct evidence that voltage signal spread in the rod-rod coupling network in the absence of I h (mediated by HCN channels) is passive and follows the linear cable equation. Under physiological conditions, I h shapes the network signal by progressively shortening the response time-to-peak of distant rods, compensating the time loss of signal traveling from distant rods to bipolar cell somas and facilitating synchronization of rod output signals. Under voltage-clamp conditions, current flow within the coupled rods follows Ohm's law, supporting the idea that nonlinear behaviors of the rod network are dependent on membrane voltage. Rod-rod coupling is largely symmetrical in the 2D array, and voltage-clamp blocking the next neighboring rod largely suppresses rod signal spread into the second neighboring rod, suggesting that indirect coupling pathways play a minor role in rod-rod coupling.

Diagnosis and monitoring denosumab therapy of giant cell tumors of bone: radiologic-pathologic correlation.

OBJECTIVE: To determine the value of CT and dynamic contrast-enhanced (DCE-)MRI for monitoring denosumab therapy of giant cell tumors of bone (GCTB) by correlating it to histopathology. MATERIALS AND METHODS: Patients with GCTB under denosumab treatment and monitored with CT and (DCE-)MRI (2012-2021) were retrospectively included. Imaging and (semi-)quantitative measurements were used to assess response/relapse. Tissue samples were analyzed using computerized segmentation for vascularization and number of neoplastic and giant cells. Pearson's correlation/Spearman's rank coefficient and Kruskal-Wallis tests were used to assess correlations between histopathology and radiology. RESULTS: Six patients (28 ± 8years; five men) were evaluated. On CT, good responders showed progressive re-ossification (+7.8HU/month) and cortical remodeling (woven bone). MRI showed an SI decrease relative to muscle on T1-weighted (-0.01 A.U./month) and on fat-saturated T2-weighted sequences (-0.03 A.U./month). Time-intensity-curves evolved from a type IV with high first pass, high amplitude, and steep wash-out to a slow type II. An increase in time-to-peak (+100%) and a decrease in Ktrans (-71%) were observed. This is consistent with microscopic examination, showing a decrease of giant cells (-76%), neoplastic cells (-63%), and blood vessels (-28%). There was a strong statistical significant inverse correlation between time-to-peak and microvessel density (ρ = -0.9, p = 0.01). Significantly less neoplastic (p = 0.03) and giant cells (p = 0.04) were found with a time-intensity curve type II, compared to a type IV. Two patients showed relapse after initial good response when stopping denosumab. Inverse imaging and pathological findings were observed. CONCLUSION: CT and (DCE-)MRI show a good correlation with pathology and allow adequate evaluation of response to denosumab and detection of therapy failure.

Evaluation of Myocardial Microcirculation in Rats under a High-Altitude Hypoxic Environment by Computed Tomography Myocardial Perfusion Imaging.

This study aims to examine the changes in myocardial microcirculation in rats in a high-altitude hypoxic environment via computed tomography (CT) myocardial perfusion imaging technology. Rats in two groups were raised in different environments from 4 weeks of age for a period of 24 weeks. At 28 weeks of age, both groups underwent CT myocardial perfusion scanning, and the following myocardial perfusion parameters were measured: time to peak (TTP), mean transit time (MTT), blood flow (BF), and blood volume (BV). Following the scan, the rats were sacrificed, the cardiac index and right ventricular hypertrophy index were obtained, and hematoxylin-eosin (HE) staining was utilized to observe the pathological changes in the myocardium. In the group of rats that are subject to a high-altitude hypoxic environment for 24 weeks (the high-altitude group), the TTP and MTT values were increased (P < 0.05), the BF and BV values were lower (P < 0.05), the right heart mass was higher (P < 0.05) than that in the low-altitude group. As shown by the pathological results of HE staining, the gap between cardiomyocytes in the high-altitude group was widened, the arrangement of cardiomyocytes was irregular, and the cells were filled with a few fat vacuoles. The myocardial microcirculation is altered in a high-altitude hypoxic environment. In particular, the myocardium is in a state of inadequate perfusion, the BF in the myocardium slows down, and the right heart displays compensatory hypertrophy.

Ascending Aorta 4D Time to Peak Distention Sexual Dimorphism and Association with Coronary Plaque Burden Severity in Women.

Coronary artery disease (CAD) risk and plaque scores are often subjective and biased, particularly in mid-age asymptomatic women, whose CAD risk assessment has been historically underestimated. In this study, a new automatic ascending aorta time-to-peak-distention (TPD) analysis was developed for fast screening and as an independent surrogate for subclinical atherosclerosis in asymptomatic women. CCTA was obtained in 50 asymptomatic adults. Plaque burden segment involvement score (SIS) and automatic TPD were obtained from all subjects. Logistic regression analyses were performed to investigate the association between CAD risk scores and TPD with severe coronary plaque burden (SIS>5). TPD, individually, was found to be a significant predictor of SIS>5. Additionally, sex was a significant effect modifier of TPD, with a stronger statistically significant association with women. Four-dimensional aortic time-to-peak distention could supplement conventional CCTA analysis and offer a quick objective screening tool for plaque burden severity and CAD risk stratification, especially in women.

Muscular and Kinematic Responses to Unexpected Translational Balance Perturbation: A Pilot Study in Healthy Young Adults.

Falls and fall-related injuries are significant public health problems in older adults. While balance-controlling strategies have been extensively researched, there is still a lack of understanding regarding how fast the lower-limb muscles contract and coordinate in response to a sudden loss of standing balance. Therefore, this pilot study aims to investigate the speed and timing patterns of multiple joint/muscles' activities among the different challenges in standing balance. Twelve healthy young subjects were recruited, and they received unexpected translational balance perturbations with randomized intensities and directions. Electromyographical (EMG) and mechanomyographical (MMG) signals of eight dominant-leg's muscles, dominant-leg's three-dimensional (3D) hip/knee/ankle joint angles, and 3D postural sways were concurrently collected. Two-way ANOVAs were used to examine the difference in timing and speed of the collected signals among muscles/joint motions and among perturbation intensities. This study has found that (1) agonist muscles resisting the induced postural sway tended to activate more rapidly than the antagonist muscles, and ankle muscles contributed the most with the fastest rate of response; (2) voluntary corrective lower-limb joint motions and postural sways could occur as early as the perturbation-induced passive ones; (3) muscles reacted more rapidly under a larger perturbation intensity, while the joint motions or postural sways did not. These findings expand the current knowledge on standing-balance-controlling mechanisms and may potentially provide more insights for developing future fall-prevention strategies in daily life.

Influence of the integrity of circle of Willis on asymptomatic or mild patients with first diagnosed chronic internal carotid artery occlusion.

BACKGROUND: In order to identify individuals with chronic internal carotid artery occlusion (CICAO), it is essential to understand the integrity of the circle of Willis (CoW). This understanding is important as it may determine the potential benefits of active medical and endovascular treatments. PURPOSE: The objective of this study is to assess whether diminished integrity of the CoW can serve as a useful marker for identifying individuals with more severe impairment in cerebral blood perfusion and a higher incidence of cerebral infarction among asymptomatic or mildly affected patients with CICAO. MATERIALS AND METHODS: We conducted a retrospective review of asymptomatic or mildly affected patients with newly diagnosed CICAO who did not receive reperfusion therapies. The categorization of patients into good or poor integrity groups was based on the assessment of CoW integrity using CTA. We evaluated the volume and value of prolonged time to peak (TTP) in both groups, as well as the occurrence of new cerebral infarctions. Our analysis involved multivariate regression and receiver operating characteristic (ROC) analysis. RESULTS: Hemodynamic abnormalities characterized by prolonged TTP were observed in the affected side's blood supply region in all 38 patients. There was a notable difference in the volume and value of prolonged TTP between the two groups (P < 0.001). Correlation analyses based on CTP and CTA parameters revealed a negative relationship between CoW scores and both the abnormal volume (r = -0.624, P = 0.000) and value (r = -0.589, P = 0.000) of prolonged TTP. Upon multivariable adjustment, the independent predictors for new cerebral infarction and higher volume of prolonged TTP were solely the CoW status, with respective estimates of (b = 6.05; 95% confidence interval [CI]: 1.619, 22.619; P = 0.007) and (b = 35.486; 95% CI: 4.697, 268.088; P = 0.001). CONCLUSION: Assessing the integrity of the CoW is crucial in evaluating abnormal perfusion in asymptomatic or mildly affected individuals who are newly diagnosed with CICAO and have not undergone reperfusion therapy.

Predicting Model of Biochemical Recurrence of Prostate Carcinoma (PCa-BCR) Using MR Perfusion-Weighted Imaging-Based Radiomics.

OBJECTIVE: To build a combined model that integrates clinical data, contrast-enhanced ultrasound, and magnetic resonance perfusion-weighted imaging-based radiomics for predicting the possibility of biochemical recurrence of prostate carcinoma and develop a nomogram tool. METHOD: We retrospectively analyzed the clinical, ultrasound, and magnetic resonance imaging data of 206 patients pathologically confirmed with prostate carcinoma and receiving radical prostatectomy at Xiangyang No. 1 People's Hospital from February 2015 to August 2021. Based on one to 7 years of follow-up (prostate specific antigen [PSA] level≥0.2 ng/mL, indicative of prostate carcinoma-biochemical recurrence), the patients were divided into biochemical recurrence group (n = 77) and normal group (n = 129). The training and testing sets were formed by dividing the patients at a 7:3 ratio. In training set, The magnetic resonance perfusion-weighted imaging-based radiomics radscore was generated using lasso regression. Several predictive models were built based on the patients' clinical imaging data. The predictive efficacy (area under the curve) of these models was compared using the MedCalc software. The decision curve analysis was conducted using the R to compare the net benefit. Finally, an external validation was carried out on the testing set, and the nomogram tool was developed for predicting prostate carcinoma-biochemical recurrence. RESULT: The univariate analysis confirmed that Tumor diameter, tumor node metastasis classification stage of tumor, lymph node metastasis or distance metastasis, Gleason grade, preoperative PSA, ultrasound (peak intensity, arrival time, and elastography grade), and magnetic resonance imaging-radscore1/2 were predictors of prostate carcinoma-biochemical recurrence. On the training set, the combined model based on the above factors had the highest predictive efficacy for prostate carcinoma-biochemical recurrence (area under the curve: 0.91; odds ratio 0.02, 95% confidence interval: 0.85-0.95). The predictive performance of the combined model was significantly higher than that of the model based on general clinical data (area under the curve: 0.74; odds ratio 0.04, 95% confidence interval: 0.67-0.81, P < .05), contrast-enhanced ultrasound (area under the curve: 0.61; odds ratio 0.05 95% confidence interval: 0.53-0.69, P < .05), and the magnetic resonance imaging-based radiomics model (area under the curve: 0.85; odds ratio 0.03, 95% confidence interval: 0.78-0.91, P = .01). The decision curve analysis also indicated the maximum net benefit derived from the combined model, which agreed with the validation results on the testing set. The nomogram tool developed based on the combined model achieved a good performance in clinical applications. CONCLUSION: The magnetic resonance imaging texture parameters extracted by magnetic resonance perfusion-weighted imaging Lasso regression could help increase the accuracy of the predictive model. The combined model and the nomogram tool provide support for the clinical screening of the populations at a risk for biochemical recurrence.

Sex hormone-mediated change on muscle activation deactivation dynamics in young eumenorrheic women.

The goal of the study was to characterize muscle activation/deactivation dynamics across the menstrual cycle in healthy young women. Twenty-two healthy eumenorrheic women (age: 27.0 ± 4.4 years; mean ± SD) were tested every other day for one menstrual cycle. Serum estradiol and progesterone were quantified at the time of testing. Peak torque (PT), time to peak torque (TPT), and half relaxation time (HRT) of soleus muscle twitch were measured. Muscle twitch was elicited by delivering 1 ms width electrical pulses to the tibial nerve at an intensity that generated a maximum motor response (S-100) and at supramaximal intensity (S-120; 1.2 × S-100). The analyses were performed for each menstrual cycle phase: 1) the follicular phase to analyze the effect of estradiol while the progesterone concentrations remained at low concentrations; 2) the luteal phase to analyze the effect of progesterone with background estradiol concentrations. In the follicular phase, there was no association of estradiol for PT, TPT, and HRT. In the luteal phase, while estradiol had no association on PT, TPT, and HRT, progesterone expressed a significant association with HRT reduction but no association on PT or TPT. Also, there was a significant estradiol and progesterone interaction for HRT. However, the regression parameters are nearly zero, suggesting that the change in HRT may not have an impact on muscle performance across the menstrual cycle but implications on other women's health conditions with elevated sex hormone concentrations, such as pregnancy, may prove critical.

Estimation of left ventricular activation sequence in patients with heart failure using two-dimensional speckle tracking echocardiography.

Evaluation of longitudinal strain (LS) from two-dimensional echocardiography is useful for global and regional left ventricular (LV) dysfunction assessment. We determined whether the LS reflects contraction process in patients with asynchronous LV activation. We studied 144 patients with an ejection fraction ≤ 35%, who had left bundle branch block (LBBB, n = 42), right ventricular apical (RVA) pacing (n = 34), LV basal- or mid-lateral pacing (n = 23), and no conduction block (Narrow-QRS, n = 45). LS distribution maps were constructed using 3 standard apical views. The times from the QRS onset-to-early systolic positive peak (Q-EPpeak) and late systolic negative peak (Q-LNpeak) were measured to determine the beginning and end of contractions in each segment. Negative strain in LBBB initially appeared in the septum and basal-lateral contracted late. In RVA and LV pacing, the contracted area enlarged centrifugally from the pacing site. Narrow-QRS showed few regional differences in strain during the systolic period. The Q-EPpeak and Q-LNpeak exhibited similar sequences characterized by septum to basal-lateral via the apical regions in LBBB, apical to basal regions in RVA pacing, and lateral to a relatively large delayed contracted area between the apical- and basal-septum in LV pacing. Differences in Q-LNpeaks between the apical and basal segments in delayed contracted wall were 107 ± 30 ms in LBBB, 133 ± 46 ms in RVA pacing, and 37 ± 20 ms in LV pacing (p < 0.05, between QRS groups). Specific LV contraction processes were demonstrated by evaluating the LS distribution and time-to-peak strain. These evaluations may have potential to estimate the activation sequence in patients with asynchronous LV activation.

Dynamic, Time-Resolved CT Angiography After EVAR: A Quantitative Approach to Accurately Characterize Aortic Endoleak Type and Identify Inflow Vessels.

PURPOSE: Our purpose was to study the accuracy of dynamic computed tomography angiography (d-CTA) in characterizing endoleak type, inflow vessels as compared with digital subtraction angiography (DSA) using qualitative and quantitative analysis. METHODS: Between March 2019 and January 2021, all patients who underwent d-CTA imaging after EVAR were retrospectively reviewed. Two blinded independent reviewers qualitatively reviewed d-CTA and DSA images. Quantitative region of interest (ROI) analysis was performed by measuring time-resolved contrast enhancement within the aorta and endoleak lesion(s) in the aneurysm sac. Differences between time-to-peak enhancement (Δ TTP) across different ROIs were quantified. RESULTS: A total of 48 patients underwent d-CTA during the study period, of whom 24 patients had abdominal EVAR and DSA imaging for comparison. Qualitative review of DSA imaging showed type I (n=4), type II (n=16), and type III (n=2) and no endoleak (n=2). In 23 of 24 patients (95.8%), d-CTA findings correlated with DSA findings for endoleak type. One patient had a type III endoleak that was demonstrated only in d-CTA (arising from defect in polymer sealing ring of Ovation stent graft) imaging. In type II endoleak cases, d-CTA identified more inflow vessels than DSA imaging (33 vs 21 vessels, p=0.010). Quantitative analysis showed mean (±SD) Δ TTP values for type I endoleak as 1.8 (±1.8) seconds, type II as 9.6 (±3.5) seconds, and for type III endoleak as 5.6 (±1.3) seconds. CONCLUSION: Dynamic CTA can accurately characterize aortic endoleak type, inflow vessels as compared with DSA imaging. Quantitative parameters such as Δ TTP enhancement can help better differentiate endoleak types and provide an objective approach to endoleak diagnosis.

Treatment of Wide-Necked Cerebral Aneurysms Using the WEB Device Including Flow Alteration Assessment With Color-Coded Imaging: A Single Center Experience.

Objective: The Woven EndoBridge (WEB) device (MicroVention, Tustin, CA) has extended the treatment of cerebral aneurysms. Despite the fact that the WEB device has shown promising clinical results, little is known about the caused intra-aneurysmal flow alterations. Here we present our clinical experience with the WEB, including examining various syngo iFlow (Siemens AG, Erlangen, Germany) parameters to predict aneurysm occlusion. Methods: We reviewed the data from patients with unruptured cerebral aneurysms treated with a WEB device between 2016 and 2020. Aneurysm occlusion and complications were assessed. Furthermore, different quantitative criteria were evaluated using syngo iFlow after digital subtraction angiography. Results: A total of 26 patients hosting 26 cerebral aneurysms met the inclusion criteria. Follow-up was available for 21 patients, with a mean of 7.3 ± 6.3 months. A total of 71.4% (n = 15) of the aneurysms included were located in the anterior and 28.6% (n = 6) in the posterior circulation. Adequate aneurysm occlusion was achieved in 85.7% (n = 18). The iFlow parameters for reduced aneurysm outflow (ID-R) differed significantly from the parameters for reduced inflow (PI-R and PI-D) (P < 0.001). The parameters did not differ significantly between adequately and insufficiently occluded aneurysms. Only a trend towards a lower ID-R of insufficiently occluded aneurysms was observed (P = 0.063), indicating a potential predictive value for insufficient aneurysmal outflow. There was no treatment-related morbidity or mortality. Conclusions: The applied syngo iFlow parameters confirmed that flow changes induced by the WEB device significantly affect outflow compared to inflow and have potential predictive value for adequate aneurysm occlusion.

Imaging features of breast cancer subtypes on contrast enhanced ultrasound: a feasibility study.

The objective of this research was to study the contrast enhancement patterns of the different molecular subtypes of breast cancer on contrast-enhanced ultrasound (CEUS) using both qualitative and quantitative parameters. This prospective study included females with a single breast mass which was histopathologically proven carcinoma. B mode ultrasound (USG) and CEUS were performed in all patients during baseline assessment. Qualitative CEUS assessment encompassed enhancement pattern, presence of fill-in and washout. Quantitative assessment included measurement of peak enhancement, time to peak; area under the curve and mean transit time. A p-value < 0.05 was considered statistically significant for differentiating the subtypes. The included thirty masses were categorised into two subtypes-triple negative breast cancer (TNBC) (36.7%) and non-TNBC (63.3%) subtypes. With B-mode USG, a statistically significant difference was observed between the two groups with respect to their shape and margins. TNBC lesions showed an oval shape, circumscribed margins and peripheral nodular enhancement on CEUS with the absence of fill-in even in the delayed phase (p-value - 0.04). The two subtypes did not significantly differ in terms of quantitative perfusion parameters. The various subtypes of breast cancer therefore possess distinct contrast enhancement patterns. CEUS potentially allows differentiation amongst these molecular subtypes that may aid in radiology-pathology (rad-path) correlation and follow up of the patients.

Role of Permeability Surface Area Product in Grading of Brain Gliomas using CT Perfusion.

Purpose The aim of this study was to evaluate the role of permeability surface area product in grading brain gliomas using computed tomography (CT) perfusion Materials and Methods CT perfusion was performed on 33 patients with brain glioma diagnosed on magnetic resonance imaging. Of these, 19 had high-grade glioma and 14 had low-grade glioma on histopathological follow-up. CT perfusion values were obtained and first compared between the tumor region and normal brain parenchyma. Then the relative values of perfusion parameters were compared between high- and low-grade gliomas. Cut-off values, sensitivity, specificity, and strength of agreement for each parameter were calculated and compared subsequently. A conjoint factor (permeability surface area product + cerebral blood volume) was also evaluated since permeability surface area product and cerebral blood volume are considered complimentary factors for tumor vascularity. Results All five perfusion parameters namely permeability surface area product, cerebral blood volume, cerebral blood flow, mean transit time, and time to peak were found significantly higher in the tumor region than normal brain parenchyma. Among these perfusion parameters, only relative permeability surface area product and relative cerebral blood volume were found significant in differentiating high- and low-grade glioma. Moreover, relative permeability surface area product was significantly better than all other perfusion parameters with highest sensitivity and specificity (97.74 and 100%, respectively, at a cut-off of 9.0065). Relative permeability surface area product had a very good agreement with the histopathology grade. The conjoint factor did not yield any significant diagnostic advantage over permeability surface area product. Conclusion Relative permeability surface area product and relative cerebral blood volume were helpful in differentiating high- and low-grade glioma; however, relative permeability surface area product was significantly better than all other perfusion parameters. Grading brain gliomas using relative permeability surface area product can add crucial value in their management and prognostication; hence, it should be evaluated in the routine CT perfusion imaging protocol.

Mode-specific effects of concentric and eccentric isokinetic training of the hamstring muscle at slow angular velocity on the functional hamstrings-to-quadriceps ratio-a randomized trial.

Background: Previous studies have examined the mode specificity of eccentric and concentric isokinetic training, but have reported conflicting results. Few studies have reported that eccentric and concentric isokinetic training are mode-specific, i.e., they will increase only the eccentric or concentric strength, respectively. Other studies have reported that mode specificity does not exist. Therefore, this study aimed to assess the mode-specific effects of eccentric and concentric isokinetic training of the hamstring muscle at slow angular velocity on eccentric peak torque of the hamstring (PTecc), concentric peak torque of the quadriceps (PTcon), acceleration time of the hamstring (AThams) and quadriceps (ATquad), deceleration time of the hamstring (DThams) and quadriceps (DTquad), time to peak torque of the hamstring (TPThams) and quadriceps (TPTquad), and functional Hamstring-to-Quadriceps ratio (PTecc/PTcon). Subjects: A total of 30 participants were randomly divided into eccentric and concentric groups. Methods: Two groups pre-test-post-test experimental design was used. In the eccentric and concentric groups, eccentric and concentric isokinetic training of hamstring muscle was performed respectively, at an angular velocity of 60°/s for 6 weeks duration. PTecc, PTcon, AThams, ATquad, DThams, DTquad, TPThams, TPTquad, and PTecc/PTcon were measured before and after the completion of training. Results: In the eccentric group, a significant difference (p < 0.05) was observed in PTecc (increased by 21.55%), AThams (decreased by 42.33%), ATquad (decreased by 28.74%), and PTecc/PTcon (increased by 17.59%). No significant difference (p > 0.05) was observed in PTcon, TPThams, TPTquad, DThams, and DTquad. In the concentric group, a significant difference (p < 0.05) was observed in PTecc (increased by 12.95%), AThams (decreased by 27.38%) ATquad (decreased by 22.08%), DTquad (decreased by 26.86%), and PTecc/PTcon (increased by 8.35%). No significant difference (p > 0.05) was observed in PTquad, TPThams, TPTquad, and DThams. Between-group analysis revealed a significant difference (p < 0.05) only in TPTquad; otherwise, in the rest of the parameters, no significant difference (p > 0.05) was observed. Conclusions: Both eccentric and concentric isokinetic training of the hamstring for 6 weeks increased PTecc, PTecc/PTcon, and decreased AThams and ATquad. The effects of eccentric and concentric isokinetic training of the hamstring on PTecc, PTecc/PTcon, AThams, and ATquad were not mode specific.

How Does Lower Limb Respond to Unexpected Balance Perturbations? New Insights from Synchronized Human Kinetics, Kinematics, Muscle Electromyography (EMG) and Mechanomyography (MMG) Data.

Making rapid and proper compensatory postural adjustments is vital to prevent falls and fall-related injuries. This study aimed to investigate how, especially how rapidly, the multiple lower-limb muscles and joints would respond to the unexpected standing balance perturbations. Unexpected waist-pull perturbations with small, medium and large magnitudes were delivered to twelve healthy young adults from the anterior, posterior, medial and lateral directions. Electromyographical (EMG) and mechanomyographical (MMG) responses of eight dominant-leg muscles (i.e., hip abductor/adductors, hip flexor/extensor, knee flexor/extensor, and ankle dorsiflexor/plantarflexors) together with the lower-limb joint angle, moment, and power data were recorded. The onset latencies, time to peak, peak values, and/or rate of change of these signals were analyzed. Statistical analysis revealed that: (1) agonist muscles resisting the delivered perturbation had faster activation than the antagonist muscles; (2) ankle muscles showed the largest rate of activation among eight muscles following both anteroposterior and mediolateral perturbations; (3) lower-limb joint moments that complied with the perturbation had faster increase; and (4) larger perturbation magnitude tended to evoke a faster response in muscle activities, but not necessarily in joint kinetics/kinematics. These findings provided insights regarding the underlying mechanism and lower-limb muscle activities to maintain reactive standing balance in healthy young adults.

Vascular Responses Among Adults Four Years Post Exposure to 6 Weeks of Smoke from the Hazelwood Coal Mine Fire.

Background and Aims: Mega-wild fires are exposing large communities to weeks or months of high concentration smoke-related fine particulate air pollution (PM). However, little research has examined the long-term vascular responses from exposure to PM of this concentration and duration. We investigated whether level of exposure to 6 weeks of PM from the 2014 Hazelwood coal mine fire was associated with abnormal vascular responses approximately four years later. Methods: A cross-sectional analysis was undertaken of 387 participants (225 exposed, 162 unexposed) aged 55-89 years, 3.5-4 years after the mine fire. The primary outcome was flow-mediated dilatation (FMD), with time to reach peak diameter as the secondary outcome. Other secondary markers included high-sensitivity C-reactive protein (hsCRP) and ischaemic Electrocardiogram (ECG) changes. Results: There was no evidence of a difference in FMD between participants with high, medium, low or no mine-fire related PM2.5 exposure (4.09% vs 4.06% vs 4.02% vs 3.98%, respectively, p=0.99). Likewise, there was no difference in hsCRP or ischaemic ECG changes. In contrast, there was evidence of a difference in time to peak diameter (p=0.002) with more unexposed participants reaching peak diameter within 30 seconds (36%) compared to those who had high, medium, or low exposure (23%, 22%, 13%, respectively). Multivariate ordinal logistic regression analysis suggested that township, Morwell (exposed) vs Sale (unexposed), but not level of PM2.5 exposure, was associated with delayed time to peak diameter (OR 2.71; 95% CI 1.56, 4.69). Smokers also had delayed time to peak diameter. Conclusion: There was no association between level of exposure to PM2.5 from the 6-week Hazelwood coal mine fire smoke event and reduced FMD, elevated hsCRP or ischaemic ECG four years later. Evidence of delayed time to peak diameter observed in adults from the exposed town, compared to an unexposed town, requires further investigation.

Neurological deterioration and computed tomography perfusion changes with increased time to peak in lacunar stroke.

OBJECTIVES: Lacunar strokes can have fluctuations and progression in the acute period leading to poor outcomes. Our study sought to evaluate if, in lacunar strokes, neurological deterioration (ND) was associated with blood pressure (BP) variations, stroke size, or increased time to peak (TTP) on admission computed tomography perfusion (CTP). METHODS: Patients with lacunar stroke who had magnetic resonance imaging and CTP performed were enrolled in the study. ND was defined as ≥1-point worsening on a modified National Institutes of Health Stroke Scale (NIHSS) score or the Medical Research Council scale compared to baseline assessment. The difference in BP between the day of admission and the day of ND was calculated. Multivariate logistic regression analysis, adjusted for pertinent clinical and imaging covariates, was performed to determine predictors of ND. RESULTS: Among 409 patients screened, 49 were eligible for the study. There was no difference in age, gender, race, medical history, admission BP, and the modified NIHSS score between patients with and without ND. In unadjusted analysis, patients with ND tended to have increased TTP in the stroke area compared to the control (12 [63%] vs. 11 [37%], P = 0.07). On multivariate analysis adjusted for covariates, presence of an increased TTP on CTP was a predictor of ND (odds ratio [95% confidence interval] = 4.80 [1.15-20.10], P = 0.03). CONCLUSION: The presence of an increased TTP on CTP corresponding to the stroke lesion on diffusion-weighted imaging is a predictor of ND in patients with lacunar stroke. Larger studies are needed to confirm our findings.