Background infusion

Nonetheless, routine use of background infusion has been questioned, especially when opioids are administered systemically (intravenously) by PCA. It appears that background infusions may not provide any additional analgesic benefits in most patients, but they can lead to an increased risk of side effects such as respiratory depression because patients ultimately receive a larger total amount of opioid (i.e., the background infusion plus the demand doses).8,34 Hence, background infusion rates have been discouraged for... 

Boselli E, Debon R, Cimino Y, et al. Background infusion is not beneficial during labor patient-controlled analgesia with 0.1% ropivacaine plus 0.5 microg/ml sufentanil. Anesthesiology. 2004 100 968-972. 

That evening s collective meal with Dave and Vanessa at our camp, with the ayahuasca infusion cooling in the background, was less than successful. By now positions relative to "the phenomenon" had polarized us into irreconcilability. Dave and Vanessa did not arrive till the close of day, but they joined us in the hut for a smoke. Discussion led to an update and final outline of the experiment proposed for the evening. Dennis spoke ... 

Different organic and inorganic buffers, such as ammonium acetate, ammonium formate, HEPES, Gly-Gly, and triethanolamine, were selected to study the response of biotin and fluorescein-biotin in MS and compared to phosphate buffer. Biotin and fluorescein-biotin were dissolved in the carrier solution compositions of buffer (10 mM pH 7.5)/methanol (50 50, v/v) at concentrations of 10 ng pl k Both infusion and 20 pl-loop injection experiments were performed with detection by MS in full-scan and SIM mode. Main optimization criteria are the maximum response of biotin and fluorescein-biotin with lowest interference of the carrier solution. HEPES, Gly-Gly, and triethanolamine give very high background response, which significantly hampers the detection of biotin and fluorescein-... 

General CE problems (e.g., wall interactions of proteins) have been discussed elsewhere. All ACE techniques working with a ligand added to CE buffer (classical ACE, Hummel-Dreyer principle, vacancy peak analysis) imply the potential problem that any continuously infused matrix can increase background noise and, even worse, deteriorate the ionization of the analyte due to competition. 

Against this background of infusible conducting polymers, the development of the soluble polythiophenes is most interesting. Glass transition temperatures have been reported as 48 °C for poly(3-butylthiophene) and 145 °C for poly(3-methyl-thiophene) 261). These polymers also show crystallinity in films and can be crystallized from solution. Solution studies indicate that there are two chain conformations 262) and the availability of a non-conjugated conformation may be a key to the low transition temperatures and solubility, when compared to the stiff-chain conjugated polymers. 

Reactivation of latent tuberculosis is a major concern with infliximab (SEDA-26, 402), and accounts for about one-third of infections in these patients. According to data from the manufacturers, 130 cases of active tuberculosis were notified up to October 2001. Many of the cases were disseminated or extrapulmonary tuberculosis, and several patients died. Several case reports have provided detailed information in at least seven other patients, including three who developed miliary tuberculosis and one who developed Mycobacterium tuberculosis enteritis (44-48). A detailed analysis of 70 cases of tuberculosis reported to the FDA has been published (49). Two-thirds of the cases were noted after three or fewer infusions and 57% of the patients had extrapulmonary disease. There were 64 cases from countries with a low incidence of tuberculosis. From these reports and the number of patients treated with infliximab, the estimated rate of tuberculosis in patients with rheumatoid arthritis treated with infliximab was four times higher than the background rate. Patients with evidence of active infection should not receive infliximab until the infection is under control all should be screened for tuberculosis before starting infliximab (50). From these and other data it has been estimated that the risk of tuberculosis in the first year of infliximab treatment is 0.035 in US citizens and 0.2% in non-US citizens. Further investigations, such as a chest X-ray and a Mantoux test, and prophylactic treatment with isoniazid, will show whether the incidence can be reduced in patients taking anti-TNF treatment (51). 

Tirofiban (i.v. infusion for 165min at 10/ig/kg/min) in the presence of background heparin enhanced the frequency and speed of reperfusion, and delayed or prevented reocclusion during the infusion period [145]. However, tirofiban failed to prevent reocclusion lh after the infusion was terminated, presumably owing to the short duration of the initially high level (>95%) of inhibition of platelet aggregation. 

The suitability of MS detectors for quantitative analyses is debated. For example, ESI is a competitive process and, occasionally, matrix (background) material interferes with the ionization of the analyte [40]. These effects of ion suppression are especially aggravated when several species coelute, such as in the case of biological extracts or with direct infusion (without previous separation). Generally, hydrophilic species are more sensitive to ion suppression than hydrophobic ones, which tend to concentrate on the droplet surface during ESI [41]. In MALDI, the sample dispersion is often inhomogeneous or the matrix crystals unevenly distributed on the surface. A truthful representation of the sample composition is obtained exclusively upon thorough laser desorption of the entire spot. In addition, with some instruments the transmission of ions in the mass... 

As an early background of its capacity to interplay with ascorbic acid, it is interesting to mention that pine bark was utilized against inflammation and also to overcome the symptoms of scurvy. Other uses of pine bark extract were suggested by the naturalist Hieronymus Bosch and included topical apphcation on skin ulcers and other skin disorders In the so-called New World, the bark of the pine was consumed by native Americans either as food or to obtain infusions to be utilized as a remedy for different diseases that are now recognized to have some free-radical involvement in inflammatory conditions. " ... 

Fig. 2 EPR effect and drug accumulation in solid tumor. (A) and (B) CT scan of human liver with hepatocellular carcinoma. When SMANCS/Lipiodol was infused arterially it was selectively taken up in the tumor. CT scan of (A) was obtained 2 days after the initial arterial infusion via a catheter, in which SMANCS/Lipiodol was selectively accumulated in the massive carcinoma seen as white area in the liver (due to high electron density of Lipiodol ). After 6 months with intermitted infusions of SMANCS two more times, tumor size (containing SMANCS) has remarkably regressed (B). (C) EPR effect in mouse sarcoma S-180 in mouse skin. Two dark blue circular areas are tumors marked by 0, where putative macro-molecular drug, Evans blue/albumin (MW 70 kDa), accumulated selectively. Note that the background of the normal skin shows no uptake of blue albumin. Mouse was killed at 6 h after the injection of Evans blue and it was quantified after extraction...

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