Rehabilitation Program for Postlaryngectomy Patients Following Ileocolon Flap Transfer for Voice Reconstruction: An Essential Part of Success.

BACKGROUND: Speech restoration is important for communication and social activities after pharyngolaryngectomy in head and neck cancer or corrosive injury. Several techniques of voice restoration have been developed to improve life quality. The aim of this paper was to focus on the microsurgical transfer of ileocolon flap and outcome of further voice rehabilitation. PATIENTS AND METHODS: From 2010 to 2022, 69 patients had ileocolon flap at our hospital with postoperative speech training and regular follow-up for over 1 year. The patients received deglutition training first, followed by voice rehabilitation. Voice outcomes were evaluated at an interval of 3 months and finally at 12 months of voice training rehabilitation. Among other examinations, the speech function was evaluated using a 4-point Likert scale and senior surgeon (H-c.C.) scoring system. RESULTS: The results showed that speech function reached 13.1% of excellent voice, 65.1% of good voice, 13.1% of fair result, and 8.7% of poor result by Likert scales. Meanwhile, the senior surgeon (H-c.C.) score showed 17.4% of excellent, 63.8% of moderate, and 18.8% of poor results. About voice laboratory results, maximal phonation time was 11.0 seconds, and the average number counted in one breath was 15. Loudness and frequency showed 56.0 dB and 105.0 Hz, respectively. CONCLUSION: The study showed that after voice reconstruction with ileocolon flap followed by the voice rehabilitation program, the patients would have a better understanding of the altered anatomical structures and practice in a more efficient way. Adequate recommendation by the therapists to plastic surgeons for revision surgeries optimized voice function of the patients.

Temporal consistency of neurovascular components on awakening: preliminary evidence from electroencephalography, cerebrovascular reactivity, and functional magnetic resonance imaging.

Sleep inertia (SI) is a time period during the transition from sleep to wakefulness wherein individuals perceive low vigilance with cognitive impairments; SI is generally identified by longer reaction times (RTs) in attention tasks immediately after awakening followed by a gradual RT reduction along with waking time. The sluggish recovery of vigilance in SI involves a dynamic process of brain functions, as evidenced in recent functional magnetic resonance imaging (fMRI) studies in within-network and between-network connectivity. However, these fMRI findings were generally based on the presumption of unchanged neurovascular coupling (NVC) before and after sleep, which remains an uncertain factor to be investigated. Therefore, we recruited 12 young participants to perform a psychomotor vigilance task (PVT) and a breath-hold task of cerebrovascular reactivity (CVR) before sleep and thrice after awakening (A1, A2, and A3, with 20 min intervals in between) using simultaneous electroencephalography (EEG)-fMRI recordings. If the NVC were to hold in SI, we hypothesized that time-varying consistencies could be found between the fMRI response and EEG beta power, but not in neuron-irrelevant CVR. Results showed that the reduced accuracy and increased RT in the PVT upon awakening was consistent with the temporal patterns of the PVT-induced fMRI responses (thalamus, insula, and primary motor cortex) and the EEG beta power (Pz and CP1). The neuron-irrelevant CVR did not show the same time-varying pattern among the brain regions associated with PVT. Our findings imply that the temporal dynamics of fMRI indices upon awakening are dominated by neural activities. This is the first study to explore the temporal consistencies of neurovascular components on awakening, and the discovery provides a neurophysiological basis for further neuroimaging studies regarding SI.

Validation of neuroimaging-based brain age gap as a mediator between modifiable risk factors and cognition.

Neuroimaging-based brain age gap (BAG) is presumably a mediator linking modifiable risk factors to cognitive changes, but this has not been verified yet. To address this hypothesis, modality-specific brain age models were constructed and applied to a population-based cohort (N = 326) to estimate their BAG. Structural equation modeling was employed to investigate the mediation effect of BAG between modifiable risk factors (assessed by 2 cardiovascular risk scores) and cognitive functioning (examined by 4 cognitive assessments). The association between higher burden of modifiable risk factors and poorer cognitive functioning can be significantly mediated by a larger BAG (multimodal: p = 0.014, 40.8% mediation proportion; white matter-based: p = 0.023, 15.7% mediation proportion), which indicated an older brain. Subgroup analysis further revealed a steeper slope (p = 0.019) of association between cognitive functioning and multimodal BAG in the group of higher modifiable risks. The results confirm that BAG can serve as a mediating indicator linking risk loadings to cognitive functioning, implicating its potential in the management of cognitive aging and dementia.

Adipose-Derived Stem Cells Preincubated with Green Tea EGCG Enhance Pancreatic Tissue Regeneration in Rats with Type 1 Diabetes through ROS/Sirt1 Signaling Regulation.

Type 1 diabetes stem-cell-based therapy is one of the best therapeutic approaches for pancreatic damage treatment due to stem cell tissue regeneration. Epigallocatechin gallate (EGCG) is one of the active components found in green tea. Experimental results suggest that EGCG shows beneficial effects on cell protection. This study explores whether a better pancreatic regeneration therapeutic effect could be found in mesenchymal stem cells pretreated with EGCG compared to stem cells without EGCG pretreatment. A cell model confirmed that adipose-derived stem cells (ADSC) incubated with EGCG increase cell viability under high-glucose (HG) stress. This is due to survival marker p-Akt expression. In an animal model, type 1 diabetes induced the activation of several pathological signals, including islet size reduction, extracellular fibrotic collagen deposition, oxidative stress elevation, survival pathway suppression, apoptosis signaling induction, and Sirt1 antioxidant pathway downregulation. Ordinary ADSC transplantation slightly improved the above pathological signals. Further, EGCG-pretreated ADSC transplantation significantly improved the above pathological conditions. Taken together, EGCG-pretreated ADSCs show clinical potential in the treatment of patients with type 1 diabetes through the regeneration of damaged pancreatic tissues.

Paraspinal soft tissue edema ratio: An accurate marker for early lumbar spine spondylodiscitis on an unenhanced MRI.

PURPOSE: MRI is currently the gold standard imaging modality in the diagnosis of lumbar spine discitis/osteomyelitis. However, even with supportive clinical and laboratory data, the accuracy of MRI remains limited by several degenerative and inflammatory mimics, such that it continues to represent a challenge for radiologists. This study reports a new quantitative imaging marker of lumbar paraspinal soft tissue edema which shows significant accuracy for spondylodiscitis. METHODS: Thirty-five patients with equivocal MRI findings of lumbar discitis/osteomyelitis vs endplate degenerative changes were reviewed over a 24-month period. Patients with a history of surgery, fractures/recent trauma, signs of advanced infection such as abscesses, phlegmon or severe osseous destruction were excluded. Two ABR board certified neuroradiologists who were blinded to the final diagnosis evaluated a new marker; the superior-inferior paraspinal edema ratio (SI-PER). The SI-PER was obtained by measuring the superior-inferior extent of increased signal/edema in the paraspinal soft tissues on the paraspinal inversion recovery images divided by the vertebral body height measured at midpoint. Cases positive for spondylodiscitis were those confirmed by biopsy, aspiration/drainage, surgery, or clinical improvement following antibiotic treatment. The diagnostic sensitivity and specificity of SI-PER were determined by Receiver operating characteristic (ROC) analysis. RESULTS: In 23/35 (66%) patients, the diagnosis of discitis/osteomyelitis was confirmed. The SI-PER showed a significant association with a positive MRI diagnosis (p = 0.001). Inter-observer correlation for SI-PER was 0.92. ROC analysis showed an area under the curve of 0.84. A SI-PER of 2.5 was 96% sensitive and 75% specific for the diagnosis of discitis/osteomyelitis, with a PPV of 88% and a NPV of 90%. CONCLUSION: In this study, the superior inferior paraspinal edema ratio (SI-PER), a newly defined MRI marker, was found to have high sensitivity for differentiating spondylodiscitis from endplate degenerative changes on lumbar spine MRI.

Differential Associations of White Matter Brain Age With Language-Related Mechanisms in Word-Finding Ability Across the Adult Lifespan.

Research on cognitive aging has established that word-finding ability declines progressively in late adulthood, whereas semantic mechanism in the language system is relatively stable. The aim of the present study was to investigate the associations of word-finding ability and language-related components with brain aging status, which was quantified by using the brain age paradigm. A total of 616 healthy participants aged 18-88 years from the Cambridge Centre for Ageing and Neuroscience databank were recruited. The picture-naming task was used to test the participants' language-related word retrieval ability through word-finding and word-generation processes. The naming response time (RT) and accuracy were measured under a baseline condition and two priming conditions, namely phonological and semantic priming. To estimate brain age, we established a brain age prediction model based on white matter (WM) features and estimated the modality-specific predicted age difference (PAD). Mass partial correlation analyses were performed to test the associations of WM-PAD with the cognitive performance measures under the baseline and two priming conditions. We observed that the domain-specific language WM-PAD and domain-general WM-PAD were significantly correlated with general word-finding ability. The phonological mechanism, not the semantic mechanism, in word-finding ability was significantly correlated with the domain-specific WM-PAD. In contrast, all behavioral measures of the conditions in the picture priming task were significantly associated with chronological age. The results suggest that chronological aging and WM aging have differential effects on language-related word retrieval functions, and support that cognitive alterations in word-finding functions involve not only the domain-specific processing within the frontotemporal language network but also the domain-general processing of executive functions in the fronto-parieto-occipital (or multi-demand) network. The findings further indicate that the phonological aspect of word retrieval ability declines as cerebral WM ages, whereas the semantic aspect is relatively resilient or unrelated to WM aging.

Exercise renovates H2S and Nrf2-related antioxidant pathways to suppress apoptosis in the natural ageing process of male rat cortex.

Ageing is a complex biological process that increases the probability of disease and death, which affects the organs of all species. The accumulation of oxidative damage in the brain contributes to a progressive loss of cognitive functions or even declined the energy metabolism. In this study, we tested the effects of exercise training on the apoptosis, survival, and antioxidant signaling pathways in the cerebral cortex of three age groups of male rats; 3, 12, and 18 months. We observed that H2S and the expression of Nrf2-related antioxidant pathways declined with age and increased after exercise training. IGF1R survival pathway was less increased in middle-aged rats; however, significantly increased after exercise training. The expression of mitochondrial-dependent apoptotic pathway components, such as Bak, cytochrome C, and caspase 3 in the ageing control group, were much higher than those of the exercise training groups. This study demonstrated that exercise training could reduce the apoptosis and oxidative stress that accrues throughout ageing, which causes brain damage.

Association Between Resistance to Cerebrospinal Fluid Flow Near the Foramen Magnum and Cough-Associated Headache in Adult Chiari Malformation Type I.

Cough-associated headaches (CAHs) are thought to be distinctive for Chiari malformation type I (CMI) patients and have been shown to be related to the motion of cerebrospinal fluid (CSF) near the foramen magnum (FM). We used computational fluid dynamics (CFD) to compute patient-specific resistance to CSF motion in the spinal canal for CMI patients to determine its accuracy in predicting CAH. Fifty-one symptomatic CMI patients with cerebellar tonsillar position (CTP) ≥ 5 mm were included in this study. The patients were divided into two groups based on their symptoms (CAH and non-CAH) by review of the neurosurgical records. CFD was utilized to simulate CSF motion, and the integrated longitudinal impedance (ILI) was calculated for all patients. A receiver operating characteristic (ROC) curve was evaluated for its accuracy in predicting CAH. The ILI for CMI patients with CAH (776 dyn/cm5, 288-1444 dyn/cm5; median, interquartile range) was significantly larger compared to non-CAH (285 dyn/cm5, 187-450 dyn/cm5; p = 0.001). The ILI was more accurate in predicting CAH in CMI patients than the CTP when the comparison was made using the area under the ROC curve (AUC) (0.77 and 0.70, for ILI and CTP, respectively). ILI ≥ 750 dyn/cm5 had a sensitivity of 50% and a specificity of 95% in predicting CAH. ILI is a parameter that is used to assess CSF blockage in the spinal canal and can predict patients with and without CAH with greater accuracy than CTP.

Reliability of Synthetic Brain MRI for Assessment of Ischemic Stroke with Phantom Validation of a Relaxation Time Determination Method.

The reliability of relaxation time measures in synthetic magnetic resonance images (MRIs) of homemade phantoms were validated, and the diagnostic suitability of synthetic imaging was compared to that of conventional MRIs for detecting ischemic lesions. Phantoms filled with aqueous cupric-sulfate (CuSO4) were designed to mimic spin-lattice (T1) and spin-spin (T2) relaxation properties and were used to compare their accuracies and stabilities between synthetic and conventional scans of various brain tissues. To validate the accuracy of synthetic imaging in ischemic stroke diagnoses, the synthetic and clinical scans of 18 patients with ischemic stroke were compared, and the quantitative contrast-to-noise ratios (CNRs) were measured, using the Friedman test to determine significance in differences. Results using the phantoms showed no significant differences in the interday and intersession synthetic quantitative T1 and T2 values. However, between synthetic and referenced T1 and T2 values, differences were larger for longer relaxation times, showing that image intensities in synthetic scans are relatively inaccurate in the cerebrospinal fluid (CSF). Similarly, CNRs in CSF regions of stroke patients were significantly different on synthetic T2-weighted and T2-fluid-attenuated inversion recovery images. In contrast, differences in stroke lesions were insignificant between the two. Therefore, interday and intersession synthetic T1 and T2 values are highly reliable, and discrepancies in synthetic T1 and T2 relaxation times and image contrasts in CSF regions do not affect stroke lesion diagnoses. Additionally, quantitative relaxation times from synthetic images allow better estimations of ischemic stroke onset time, consequently increasing confidence in synthetic MRIs as diagnostic tools for ischemic stroke.

Clinical utility of 2-D anatomic measurements in predicting cough-associated headache in Chiari I malformation.

PURPOSE: Cough-associated headache (CAH) is the most distinctive symptom of patients with Chiari I malformation (CMI) and indicates clinically significant disease. We determined the clinical utility of simple 2D anatomic measurements performed on a PACS workstation by assessing their diagnostic accuracy in predicting CAH in CMI patients. METHODS: Seventy-two consecutive CMI patients (cerebellar tonsillar herniation > 5 mm) with headache seen by neurosurgeons over 6 years were included. Sagittal T1 images were used by two readers to measure: extent of tonsillar herniation, lengths of the clivus and supra-occiput, McRae and pB-C2 lines, as well as clivus-canal, odontoid retroversion, and skull base angles. Neurosurgery notes were reviewed to determine presence of CAH. Mann-Whitney test was used to compare measurements between patients with and without CAH. Predictive accuracy was assessed by receiver operating characteristic (ROC) curve. RESULTS: 47/72 (65.3%) CMI patients reported CAH. Tonsillar herniation with CAH (10.2 mm, 7-14 mm; median, interquartile range) was significantly greater than those without CAH (7.9 mm, 6.3-10.9 mm; p = 0.02). Tonsillar herniation ≥ 10 mm showed sensitivity and specificity of 51% and 68%, and tonsillar herniation > 14 mm showed sensitivity and specificity of 30% and 100%, respectively, for predicting CAH. Other 2D measurements showed no statistically significant differences. CONCLUSIONS: Among the 2D measurements used, only the extent of tonsillar herniation is different between CMI patients with and without CAH. Although CMI is diagnosed with tonsillar herniation of only 5 mm, we found that a much higher extent of herniation is needed to be predictive of CAH.

In Situ Diagnosis of Industrial Motors by Using Vision-Based Smart Sensing Technology.

This study uses machine vision, feature extraction, and support vector machine (SVM) to compose a vibration monitoring system (VMS) for an in situ evaluation of the performance of industrial motors. The vision-based system respectively offers a spatial and temporal resolution of 1.4 µm and 16.6 ms after the image calibration and the benchmark of a laser displacement sensor (LDS). The embedded program of machine vision has used zero-mean normalized correlation (ZNCC) and peak finding (PF) for tracking the registered characteristics on the object surface. The calibrated VMS provides time-displacement curves related to both horizontal and vertical directions, promising remote inspections of selected points without attaching additional markers or sensors. The experimental setup of the VMS is cost-effective and uncomplicated, supporting universal combinations between the imaging system and computational devices. The procedures of the proposed scheme are (1) setting up a digital camera, (2) calibrating the imaging system, (3) retrieving the data of image streaming, (4) executing the ZNCC criteria, and providing the time-displacement results of selected points. The experiment setup of the proposed VMS is straightforward and can cooperate with surveillances in industrial environments. The embedded program upgrades the functionality of the camera system from the events monitoring to remote measurement without the additional cost of attaching sensors on motors or targets. Edge nodes equipped with the image-tracking program serve as the physical layer and upload the extracted features to a cloud server via the wireless sensor network (WSN). The VMS can provide customized services under the architecture of the cyber-physical system (CPS), and this research offers an early warning alarm of the mechanical system before unexpected downtime. Based on the smart sensing technology, the in situ diagnosis of industrial motors given from the VMS enables preventative maintenance and contributes to the precision measurement of intelligent automation.

Performance of On-Call Radiology Residents in Interpreting Total Spine MRI Studies for the Detection of Spinal Cord Compression or Cauda Equina Compression.

OBJECTIVE. Accurate diagnosis of spinal cord compression (SCC) or cauda equina compression (CEC) is important in the emergency setting so management decisions may be made promptly. The purpose of this study is to evaluate the performance of on-call radiology residents in interpreting total spine MRI studies for the detection of SCC or CEC. MATERIALS AND METHODS. On-call radiology residents' preliminary interpretation of total spine MRI studies performed over a period of two and half years were evaluated. Agreements and disagreements were determined for SCC (defined as severe spinal stenosis with compression of the spinal cord and lack of surrounding CSF), CEC (defined as > 75% narrowing of the lumbar canal and lack of CSF in the thecal sac), and the presence of other significant findings that might impact clinical management. Studies with true-positive, true-negative, false-positive, and false-negative findings were identified. RESULTS. SCC or CEC was present in 72 of the 295 studies with preliminary interpretations done by on-call residents. The sensitivity and specificity for detecting SCC or CEC were 93.1% and 98.2%, respectively. Sensitivity was higher for 3rd- and 4th-year residents (97.7%) than for 2nd-year residents (86.2%). Other significant findings were present in 34 of the 295 studies. The overall sensitivity and specificity for the detection of other significant findings were 85.3% and 100.0%, respectively. The level of training did not affect the detection of other significant findings. CONCLUSION. The overall sensitivity of on-call radiology residents' interpretation of total spine MR images for the detection of SCC or CEC was high, improving with their level of training. However, residents' sensitivity was slightly less for the detection of other significant findings. Resident performance can be further improved with focused training and the use of a preliminary interpretation template.

Lumbar muscle volume in postmenopausal women with osteoporotic compression fractures: quantitative measurement using MRI.

OBJECTIVE: To investigate the relationship between paraspinal and psoas muscle volumes and acute osteoporotic or low-bone-mass compression fractures of the lumbar spine in postmenopausal women. METHODS: Patient data were retrieved retrospectively for postmenopausal women with L-spine magnetic resonance imaging (MRI) and dual-energy X-ray absorptiometry showing osteoporosis/low bone mass. Group 1 comprised eight women aged 60-80 years with MRI showing a single acute compression fracture. The age-matched group 2a (N = 12) and younger group 2b (N = 12) comprised of women whose MRIs showed no fractures. Cross-sectional MRIs of the paraspinal and psoas muscles and intramuscular fat volume for each muscle group were measured. Operator repeatability and reproducibility were obtained. RESULTS: Group 1 showed significantly smaller lean muscle volume for all muscle groups at L5/S1. Intramuscular fat volume was also smaller in most muscle groups in group 1, though only reaching statistical significance at variable muscle groups and levels. Measurements show both good intrarater repeatability and interrater reproducibility of lean muscle volume estimations (intraclass correlation coefficient (ICC), 0.999 for rater A and 0.997 for rater B; Cronbach's alpha 0.995) and intramuscular fat volume estimations (ICC, 0.995 for rater A and 0.982 for rater B; Cronbach's alpha was 0.981). CONCLUSIONS: This study provides the first quantitative evidence that compression fractures in postmenopausal women with underlying osteoporosis/low bone mass are associated with less paraspinal and psoas muscle volumes. Further longitudinal studies with larger cohorts are needed to verify this relationship. KEY POINTS: • The risk of osteoporotic compression fractures is higher in older women with smaller paraspinal muscle volume. • Older women show smaller paraspinal muscle volume and more intramuscular fat compared to younger controls.

Multicenter integrated positron emission tomography/computer tomography imaging quality assurance accreditation interobserver reliability study with the American College of Radiology phantom.

BACKGROUND: Integrated positron emission tomography/computer tomography (PET/CT) image quality assurance ensures accurate, reproducible, and quantitative assessment of comparable scanner performance. We performed a preliminary multicenter PET/CT imaging quality assurance test with a fillable tomographic phantom in six medical centers in Taiwan. METHODS: The phantom was filled with fixed proportions of fluorine-18 radionuclide solution in the background and with different spheres to simulate cold and hot lesions, and body background radioactivity. Imaging acquisitions were performed by using recommended parameters in different sites according to different brand names of the instrument. All imaging was subjectively scored by eight experienced nuclear medicine physicians as the spatial resolution of four hot vials (score 0-4), six cold spheres (score 0-6), and six cold rod areas (score 0-6), and overall satisfaction (score 0-5). Interobserver correlation and receiver operating characteristic (ROC) curve were analyzed. RESULTS: The detection ability of hot vials, cold spheres, and cold rods was 4.0 ± 0.1, 5.2 ± 0.8, and 3.8 ± 0.9, respectively. Overall satisfaction was 4.0 ± 0.8. The ROC analysis revealed that the area under the curve for hot vials, cold spheres, and cold rods was 0.984, 0.887, and 0.928 respectively. The interobserver correlation for detectability of cold spheres and cold rods was 0.88 and 0.96, respectively. CONCLUSION: The results of the study indicated that (1) PET/CT imaging quality assurance for comparable scanner performance could be established on the basis of a standard phantom and (2) good interobserver correlation can be observed for those with accurate and interpretable results.

Quantitative maternal hepatitis B surface antigen predicts maternally transmitted hepatitis B virus infection.

Despite immunoprophylaxis, hepatitis B virus (HBV) transmission in highly viremic mothers remains a global health issue. Using quantitative maternal surface antigen (HBsAg) to predict HBV infection in infants has not been investigated. We enrolled 526 mother-infant pairs with positive maternal HBsAg under current immunoprophylaxis. Maternal viral load and quantitative HBsAg were measured in the peripartum period. Infant HBsAg seropositivity for more than 6 months was defined as chronic infection. Rates of chronic infection in infants at various maternal HBsAg levels were estimated using a multivariate logistic regression model. Results showed that maternal HBsAg was positively correlated with maternal viral load (r = 0.69; P < 0.001) and accurately predicted maternal viral load above 6, 7, and 8 log10 IU/mL with an area under the receiver operating characteristic curve (AUC) of 0.97, 0.98, and 0.95. Nineteen infants were chronically infected. After adjustment for the other risk factor, maternal HBsAg level was significantly associated with risk of infection (adjusted odds ratio for each log10 IU/mL increase, 15.02; 95% confidence interval [CI], 3.89-57.94; P < 0.001). The AUC for predicting infection by quantitative maternal HBsAg was comparable to that by maternal viral load (0.89 vs. 0.87; P = 0.459). Estimated rates of infection at maternal HBsAg levels of 4, 4.5, and 5 log10 IU/mL were 2.4% (95% CI, 0.1-4.6; P = 0.04), 8.6% (95% CI, 4.5-12.7; P < 0.001), and 26.4% (95% CI, 12.6-40.2; P < 0.001). CONCLUSION: Quantitative maternal HBsAg predicts infection in infants as well as maternal viral load does. Antiviral therapy may be considered in pregnant women with an HBsAg level above 4-4.5 log10 IU/mL to interrupt mother-to-infant transmission. (Hepatology 2016;64:1451-1461).

Improving Bone Microarchitecture in Aging with Diosgenin Treatment: A Study in Senescence-Accelerated OXYS Rats.

Osteoporosis is a major disease associated with aging. We have previously demonstrated that diosgenin prevents osteoporosis in both menopause and D-galactose-induced aging rats. OXYS rats reveal an accelerated senescence and are used as a suitable model of osteoporosis. The aim of the present study was to analyze microarchitecture and morphological changes in femur of OXYS rats using morphological tests and microcomputed tomography scanning, and to evaluate the effects of oral administration of diosgenin at 10 and 50 mg/kg/day on femur in OXYS rats. The result showed that, compared with age-matched Wistar rats, the femur of OXYS rats revealed lower bone length, bone weight, bone volume, frame volume, frame density, void volume, porosity, external and internal diameters, cortical bone area, BV/TV, Tb.N, and Tb.Th, but higher Tb.Sp. Eight weeks of diosgenin treatment decreased porosity and Tb.Sp, but increased BV/TV, cortical bone area, Tb.N and bone mineral density, compared with OXYS rats treated with vehicle. These data reveal that microarchitecture and morphological changes in femur of OXYS rats showed osteoporotic aging features and suggest that diosgenin may have beneficial effects on aging-induced osteoporosis.

Effective enhancement of fluorescence detection efficiency in protein microarray assays: application of a highly fluorinated organosilane as the blocking agent on the background surface by a facile vapor-phase deposition process.

Protein microarrays are emerging as an important enabling technology for the simultaneous investigation of complicated interactions among thousands of proteins. The solution-based blocking protocols commonly used in protein microarray assays often cause cross-contamination among probes and diminution of protein binding efficiency because of the spreading of blocking solution and the obstruction formed by the blocking molecules. In this paper, an alternative blocking process for protein microarray assays is proposed to obtain better performance by employing a vapor-phase deposition method to form self-assembled surface coatings using a highly fluorinated organosilane as the blocking agent on the background surfaces. Compared to conventional solution-based blocking processes, our experimental results showed that this vapor-phase process could shorten the blocking time from hours to less than 10 min, enhance the binding efficiency by up to 6 times, reduce the background noise by up to 16 times, and improve the S/N ratio by up to 64 times. This facile blocking process is compatible with current microarray assays using silica-based substrates and can be performed on many types of silane-modified surfaces.

Autonomic nervous system mediates the cardiovascular effects of Rhodiola sacra radix in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Rhodiola sacra (Crassulaceae) exhibits cardiovascular bioactivities and is used in Tibetan medicine for promoting circulation and preventing hypertension. However, the underlying mechanisms of its cardiovascular effects are poorly understood. AIM OF THE STUDY: The aim of this study was therefore to evaluate the cardiovascular activity of water-soluble fraction (WtF) and n-butanol-soluble fraction (BtF) of Rhodiola sacra radix and to explore its mechanism of action in propofol anesthetized Sprague-Dawley rats. MATERIALS AND METHODS: The changes of blood pressure, heart rate and cardiac contractility after systemic administration of the extracts (10-75 mg/kg) were examined for at least 40 min. Different antagonists were used to evaluate the mechanisms of cardiovascular effects of the extracts. RESULTS: Intravenous injection of the WtF (10, 25, 35, 50 or 75 mg/kg) exhibited dose-dependent hypotension and increases in heart rate and cardiac contractility. In contrast, mild alterations in the same cardiovascular parameters were detected only at high dose (75 mg/kg) BtF. The WtF-induced hypotensive, positive inotropic and chronotropic effects were significantly abolished by pretreatment with hexamethonium (30 mg/kg, i.v.) or reserpine (5 mg/kg, i.v.), whereas the hypotensive, but not the positive inotropic or chronotropic effect was potentiated by captopril (2.5 mg/kg, i.v.). Pretreatment with methylatropine (1 mg/kg, i.v.), on the other hand, reversed the positive inotropic and chronotropic but not the hypotensive effects of WtF. The WtF-induced cardiovascular responses were not affected in rats pretreated with N(G)-nitro-l-arginine methyl ester (20 mg/kg, i.v.). CONCLUSIONS: We conclude that systemic administration of the WtF of Rhodiola sacra radix elicited a potent hypotensive effect that was mediated by the withdrawal of sympathetic vasomotor tone and interaction with the circulatory angiotensin system. The positive inotropic and chronotropic effects of WtF may result from a direct vagal inhibition on the heart.