Intradialysis hypertension is a frustrating complication among hemodialysis (HD) patients. This study was conducted to investigate the physiological changes during intradialytic hypertension. The beat-to-beat continuous heart rate, hematocrit (Hct) changes during HD, serum levels of nitric oxide, plasma levels of catecholamine, renin, endothelin (ET-1), cardiac output (CO), and peripheral vascular resistance (PVR) were measured before and after HD in patients prone to develop intradialysis hypertension (n = 30) and from age, sex-matched control HD subjects (n = 30). It was found that the baseline values of Hct, serum levels of nitric oxide, plasma levels of catecholamine, renin, and ET-1, CO, PVR, and power index (low frequency/high frequency ratios) of heart rate variability were not significantly different between the patients and control subjects. In the hypertension-prone group, the plasma levels of catecholamine, renin, and the serial measurements of power index, did not show significant changes. However, the patients showed a significant elevation of systemic vascular resistance (56.8 +/- 9.2% vs 17.7 +/- 9.5; P < 0.05), ET-1 (510.9 +/- 43.3 vs 276.7 +/- 30.1 pg/ml; P < 0.05) and a significant decrease of nitric oxide (NO)/ET-1 balance (0.018 +/- 0.003 vs 0.034 +/- 0.005; P < 0.05) at the end of HD compared with the control patients. It was found that the physiological changes in intradialysis hypertension patients were characterized by inappropriately increased PVR through mechanisms that did not involve sympathetic stimulation or renin activation but might be related with altered NO/ET-1 balance.

The three-dimensional spatial arrangement of the cortical microcirculatory system is critical for understanding oxygen exchange between blood vessels and brain cells. A three-dimensional computer model of a 3 × 3 × 3 mm3 subsection of the human secondary cortex was constructed to quantify oxygen advection in the microcirculation, tissue oxygen perfusion, and consumption in the human cortex. This computer model accounts for all arterial, capillary and venous blood vessels of the cerebral microvascular bed as well as brain tissue occupying the extravascular space. Microvessels were assembled with optimization algorithms emulating angiogenic growth; a realistic capillary bed was built with space filling procedures. The extravascular tissue was modeled as a porous medium supplied with oxygen by advection–diffusion to match normal metabolic oxygen demand. The resulting synthetic computer generated network matches prior measured morphometrics and fractal patterns of the cortical microvasculature. This morphologically accurate, physiologically consistent, multi-scale computer network of the cerebral microcirculation predicts the oxygen exchange of cortical blood vessels with the surrounding gray matter. Oxygen tension subject to blood pressure and flow conditions were computed and validated for the blood as well as brain tissue. Oxygen gradients along arterioles, capillaries and veins agreed with in vivo trends observed recently in imaging studies within experimental tolerances and uncertainty.

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Cerebrospinal fluid (CSF) is not stagnant but displays fascinating oscillatory flow patterns inside the ventricular system and reversing fluid exchange between the cranial vault and spinal compartment. This review provides an overview of the current knowledge of pulsatile CSF motion. Observations contradicting classical views about its bulk production and clearance are highlighted. A clinical account of diseases of abnormal CSF flow dynamics, including hydrocephalus, syringomyelia, Chiari malformation type 1, and pseudotumor cerebri, is also given. We survey medical imaging modalities used to observe intracranial dynamics in vivo. Additionally, we assess the state of the art in predictive models of CSF dynamics. The discussion addresses open questions regarding CSF dynamics as they relate to the understanding and management of diseases. 219 P R E V I E WFL48CH09-Linninger ARI

The findings indicated that patients in the periodontitis cohort exhibited a higher risk of developing oral cancer than those in the gingivitis cohort.

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In this study, we aimed to provide a large-scale set of psycholinguistic norms for 3,314 traditional Chinese characters, along with their naming reaction times (RTs), collected from 140 Chinese speakers. The lexical and semantic variables in the database include frequency, regularity, familiarity, consistency, number of strokes, homophone density, semantic ambiguity rating, phonetic combinability, semantic combinability, and the number of disyllabic compound words formed by a character. Multiple regression analyses were conducted to examine the predictive powers of these variables for the naming RTs. The results demonstrated that these variables could account for a significant portion of variance (55.8 %) in the naming RTs. An additional multiple regression analysis was conducted to demonstrate the effects of consistency and character frequency. Overall, the regression results were consistent with the findings of previous studies on Chinese character naming. This database should be useful for research into Chinese language processing, Chinese education, or crosslinguistic comparisons. The database can be accessed via an online inquiry system (http://ball.ling.sinica.edu.tw/ namingdatabase/index.html).Keywords Naming . Chinese character naming . Psycholinguistic norm . Chinese visual word recognition Understanding how readers process words, which are fundamental units for reading, has been a core issue in psycholinguistic studies. Behavioral studies have utilized tasks such as naming, lexical decision, speech perception, and synonym judgment, with the aim of understanding how orthographic, phonological, and semantic information is processed during visual word recognition. These experiments have typically employed a factorial design by manipulating one or two lexical variables (e.g., word frequency and spelling-to-sound consistency) in a limited set of stimuli, while trying to control for other lexical variables (e.g., orthographic neighborhood size and acoustic properties of onsets) in order to prevent any potential confounds. Although this approach has provided fruitful evidence to advance our understanding of how various lexical properties affect visual word recognition, it has some limitations in terms of how to select a set of items that vary in only one dimension and how to generalize the findings to a larger set of stimuli.To overcome these limitations, a number of large-scale psycholinguistic databases have been made available for languages with alphabetic orthographies, including English (Balota et al

Denosumab is effective in restoring bone mass and reducing bone pain in patients on dialysis with secondary hyperparathyroidism. It also allows for a more aggressive use of calcitriol to control hyperparathyroidism.