Extent of autonomic activation following cerebral ischemia is different in hypertensive and normotensive humans

OBJECTIVES: To evaluate whether the extent of autonomic activation following brain infarction differs between hypertensive and normotensive humans, and to investigate the role of the insular cortex for this sympathetic activation. DESIGN: Prospective, hospital-based study. SETTING: Department of Neurology of a university medical center. SUBJECTS: Forty-two patients with essential hypertension and 45 patients who were normotensive. MAIN OUTCOME MEASURES: Extent of autonomic activation following stroke as indicated by circadian blood pressure patterns, serum norepinephrine levels, and cardiovascular variables. RESULTS: Normotensive patients with insular infarction showed a significantly reduced circadian blood pressure variation and a higher frequency of nocturnal blood pressure increase compared with patients suffering from essential hypertension and insular stroke. These findings were also associated with higher serum norepinephrine concentrations and more frequent electrocardiographic abnormalities. No significant changes in these variables were seen between normotensive and hypertensive patients without insular involvement. CONCLUSIONS: Our findings suggest a difference in cortical control of autonomic function between hypertensive and normotensive patients after stroke and point to a possible role of the insular cortex in the pathogenesis of essential hypertension.     

Hypertrophied cauda equina presenting as intradural mass: case report and review of literature

BACKGROUND: Hereditary motor and sensory neuropathy types I and III usually lead to enlargement of peripheral nerves. Rarely, spinal nerve roots may also be involved, leading to radiculopathy and/or myelopathy. METHODS: This 44-year-old man with back and lower extremity radicular pain and distal lower extremity weakness and numbness was found to have a nonenhancing intradural mass that caused a nearly complete myelographic block from L1-L4. He underwent a decompressive laminectomy with intradural exploration. RESULTS: Hypertrophic but otherwise normal-looking nerve roots were observed. Subsequent electrodiagnostic testing and sural nerve biopsy confirmed that this patient had a previously unsuspected hereditary motor and sensory neuropathy (HMSN). His pain resolved, but at latest follow-up his weakness and numbness persisted. CONCLUSIONS: Nonenhancing spinal intradural mass lesions may represent enlarged nerve roots, which have a number of potential etiologies. Electrodiagnostic studies and peripheral nerve biopsy are instrumental in establishing the diagnosis of HMSN.     

Role expectation and role performance in distressed and normal couples.

To determine the relative importance of role expectations vs role performances in differentiating distressed from nondistressed couples, the Kelly-Tharp Marital Role Questionnaire was administered to 26 couples seeking psychiatric services and to 26 matched control couples. Distressed and nondistressed Ss were found to reflect very similar responses on expectation items and highly dissimilar responses on corresponding enactment items—findings that were particularly striking for items within the Sexuality and Solidarity scales. Methodological and theoretical considerations relevant to these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of norepinephrine on aortic 42K turnover during deoxycorticosterone acetate hypertension and antihypertensive therapy in the rat

We studied the effects of norepinephrine on 42K turnover in aorta isolated from rats. The rats were given saline to drink and were made hypertensive by injections of deoxycorticosterone acetate (DOC). Other groups of rats received in addition either 6-hydroxydopamine (6-OH-DA) or a regimen of antihypertensives (Anti-Hy) consisting of reserpine, hydrochlorothiazide, and hydralazine. The weight, length, wall thickness, and circumference of the aorta also were measured. DOC hypertension was associated with increased 42K turnover (rate constant for DOC = 0.0164 +/- 0.0009 vs. 0.0090 +/- 0.0002 min-1 in controls). The responses of 42K turnover to low doses of norepinephrine (NE) were increased in DOC with an ED50 of 3.5 +/- 0.8 X 10(-9) vs. 2.7 +/- 0.5 X 10(-8) M in controls. The aortic weight, weight/length, and wall thickness were also increased. Rats treated with DOC plus 6-OH-DA had lower blood pressure and smaller changes in aortic dimensions; however 42K turnover and response to NE were similar to those of the DOC group. The Anti-Hv group exhibited only small increase in 42K turnover and aortic dimensions when compared to controls. It is concluded that DOC hypertension is associated with increased response of 42K turnover to NE which in turn may contribute to increased responses reported for contraction. The Anti-Hy regimen was more effective than 6-OH-DA in reducing the increased 42K turnover and response to NE associated with DOC hypertension.     

Zeitstandbruchverhalten einiger warmfester Stähle unter rechteckzyklisch veränderter Spannung oder Temperatur

Zeitstandversuche bis 10 000 h unter veränderlicher Spannung oder Temperatur an fünf ferritischen Stählen mit 0,10 bis 0,21% C, bis 12% Cr, 0,30 bis 1,1% Mo und bis 0,35% V sowie einem austenitischen Stahl mit 0,065% C, 1,62% Mn, 16,5% Cr, 2,16% Mo und 13,3% Ni. Zuverlässigkeit bekannter einfacher Regeln zur Vorhersage der Beanspruchungsdauer bis zum Bruch unter veränderlicher Spannung oder Temperatur und Unterschiede zwischen dem Verhalten verschiedener Stahlsorten.     

A Thermodynamic Model of the EAF Process for Stainless Steel

A time‐dependent thermochemical model has been developed for the electric arc furnace (EAF) process for stainless steel production. Time dependency is implemented by a stepwise input of energy and matter into an equilibrium reactor. The equilibrium calculations are performed using data from FACT‐databases and implemented using the programming library ChemApp. The material input for the model was generated by reconciliation of industrial data and the energy input is approximated from the industrial data and scaled through an efficiency factor. The model is used to calculate the evolution of temperature and composition of gas, slag and metal phases with time. Agreement of the end composition in the metal phase with industrial data is good. In the slag phase, however, Cr, Fe, Mn and Si are oxidized significantly less than expected due to excess formation of CO‐gas. The dynamics of the slag composition are examined in more detail. Here a fair agreement is reached for the main slag components. However, for Cr, Fe and Mn the model cannot predict the dynamics, which seem to be strongly kinetically controlled. The results of the equilibrium model can thus provide some insight into the kinetics of the process.     

Advances in developing high-performance calendering formulations: Barium/cadmium stabilized plasticized PVC for outdoor use

Laboratory tests were intended to show differences in processing and weatherability which occur when various powdered and liquid barium/cadmium stabilizers are used alone and in combination with epoxy plasticizer and phosphite. The results show that in the selection of stabilizers it is not necessarily the metal content of the stabilizer which is important, but rather that optimum weathering stability is achieved by the correct combination of complex barium, cadmium and zinc components. Liquid barium/cadmium/zinc compounds of the IRGASTAB BC 445 type, combined with epoxy plasticizer and phosphite, give optimum stabilization of plasticized PVC, ease of processing and excellent weatherability.     

Thermostabile Polymere. II. Polycyclotriphosphazenamide (Polykondensate aus 2,2,4,6-Tetrakis-(dimethylamido)-4,6-dichloro-cyclotriphosphazen und aromatischen Diaminen)

Polycondensation of 2.2.4.6-tetrakis-(dimethylamido)-4.6-dichloro-cyclotriphos-phazene and aromatic diamines in boiling pyridine yields high-molecular weight polymers. The polycondensates are soluble in organic solvenst and can be moulded at temperatures between 150 and 200°C. When the polymers are heated at 250°C, dimethylamine is abstracted and foamed plastics are formed, which are thermostable at temperatures up to, say, 550°C. The foamed products have a very good compressive strength. The polymers may possibly be used as fire-retarding agents, ablative and insulating materials.     

Molecular dynamics simulations of alkylsilane stationary-phase order and disorder. 2. Effects of temperature and chain length

In an effort to elucidate the molecular-level structural features that control shape-selective separations, we have investigated the molecular dynamics of chromatographic models that represent both monomeric and polymeric stationary phases with alkylsilane length and temperature conditions analogous to actual materials of low to high shape selectivity. The structural characterization of these models is consistent with previous experimental observations of alkyl chain order and disorder: alkyl chain order increases both with alkyl chain length and with reduced temperature. Models that represent shape-selective reversed-phase liquid chromatography (RPLC) phases possess a significant region of distal end chain order with primarily trans dihedral angle conformations; the extension of these ordered regions into the phase increases with an increase in chain length. Models with extended chain length (C30) possess a higher degree of conformational order and are relatively insensitive to changes in surface coverage, bonding chemistry, and temperature. Chromatography models of various chain lengths and over a temperature range that represents highly shape-selective RPLC stationary phases all contain a series of well-defined and rigid cavities; the size and depth of these "slots" increase for the C30 models, which may promote the enhanced separations of larger size shape-constrained solutes, such as carotenoids.     

A calorimeter for small samples in the temperature range from 0.06 K to 3 K

A convenient method to measure very small heat capacities at low temperatures (0.06 K to 3 K) is described. It allows the detection of heat capacities of less than 10^?9 J K^?1 at 0.1 K. The equipment is checked by measuring a small amount (≈ 40 mg) of Cu whose heat capacity is found to agree very well with other work.