Artelinic acid (6d) and Metaartelic acid (8), water soluble dihydroartemisinin derivatives with antimalarial activity, were prepared by direct etherification of dihydroartemisinin (2) with appropriate hydroxymethyl z=benzoic acid.
Sesquiterpenes ; Ethers

No abstract available.
Anesthesia ; Dihydroergotamine ; Methyl Ethers

Humans ; Methyl Ethers ; toxicity ; Occupational Exposure

Halogenated Diphenyl Ethers ; adverse effects ; Humans

No abstract available.
Anesthesia ; Epilepsy ; Humans ; Methyl Ethers ; Status Epilepticus

To clarify the content characteristics of the main active components and mineral elements of Cynomorium songaricum under different habitat conditions, and further explore the relationship between the quality of C. songaricum and habitats, this study took C. songaricum from 25 different habitats in China as the research object, and measured the contents of 8 main active components and 12 mineral elements separately. Diversity analysis, correlation analysis, principal component analysis and cluster analysis were carried out. The results showed that the genetic diversity of total flavonoids, ursolic acid, ether extract, potassium(K), phosphorus(P) and zinc(Zn) in C. songaricum was high. The coefficient of variation of crude polysaccharide, ether extract, gallic acid, protocatechuic aldehyde, catechin, epicatechin, calcium(Ca), sodium(Na), magnesium(Mg), sulfur(S), iron(Fe), manganese(Mn), selenium(Se) and nickel(Ni) were all over 36%, indicating that the quality of C. songaricum was significantly affected by habitats. There were strong synergistic and weak antagonistic effects among the contents of the 8 active components, and complex antagonistic and synergistic effects among the contents of the 12 mineral elements. Principal component analysis revealed that crude polysaccharide, ursolic acid, catechin, epicatechin and total flavonoids could be used as the characteristic components to evaluate the quality of C. songaricum, and Na, copper(Cu), Mn and Ni were the characteristic elements to evaluate the quality of C. songaricum. In cluster ana-lysis, the second group with the main active components as cluster center had better quality in terms of the content of active substances, and the second group with the mineral elements as cluster center had higher utilization potential in the exploitation of mineral elements. This study could provide a basis for resource evaluation and breeding of excellent varieties of C. songaricum in different habitats, and provide a reference for cultivation and identification of C. songaricum.
Cynomorium ; Catechin ; Plant Breeding ; Selenium ; Ethers ; Ethyl Ethers ; Flavonoids ; Plant Extracts

BACKGROUND: Sevoflurane and desflurane are widely used anesthetics and can be simulated in pharmacokinetic models. These models are related to steady state pharmacokinetics, As anesthetic elimination is a non-steady state process, we evaluated the elimination data of volatile anesthetics using a two-compartment model (bi-exponential function). 50, 80, and 90% context-sensitive decrement times were evaluated with this function. These times are related to awakening and cognitive function recovery. METHODS: Forty-eight healthy patients were enrolled for minimal surgery under general anesthesia. They were randomly anesthetized with either sevoflurane or desflurane. At the end of surgery, when the administration of the volatile anesthetics was discontinued, end-tidal concentrations (PE) were recorded for 15 minutes. We calculated and analyzed the fraction of anesthetic concentrations (PE/PE0) using a bi-exponential function (PE0: the last end-tidal concentration of anesthetics during anesthesia). RESULTS: A bi-exponential function was fit to the elimination data using non-linear mixed-effect modeling. It showed that the anesthetic duration had effects on the coefficients of early and late components and not on the log rate constants. The coefficient of late components increased and the coefficient of early components decreased with prolonged anesthetic duration. Irrespective to the type of anesthetics, prolonged anesthesia did not affect the context-sensitive half-life; however, a prolonged period of time was required to reach 80 and 90% decrement after prolonged anesthesia. CONCLUSIONS: Prolonged anesthetic duration slowed down the elimination of volatile anesthetics. It delayed awakeness and a return to normal cognitive function after anesthesia.
Anesthesia ; Anesthesia, General ; Anesthetics ; Humans ; Isoflurane ; Methyl Ethers

An ideal reversal agent could be given at any time after the administration of a neuromuscular blocking agent, and should have no muscarinic side-effects. Sugammadex is a modified gamma-cyclodextrin designed to encapsulate rocuronium bromide, providing a rapid reversal of neuromuscular blockade. Sugammadex is a revolutionary investigational reversal drug currently undergoing Phase III testing whose introduction into clinical practice in Korea may change the face of clinical neuromuscular pharmacology. The dose of sugammadex for reversal of moderate block (when T2 is detectable) is approximately 2 mg/kg, the dose is 4-8 mg/kg for profound block (post-tetanic count 1-2) and a larger dose of 16 mg/kg for immediate reversal. The use of sugammadex has not been reported to be associated with recurrence of block provided a dose that is adequate for reversal has been used. Sugammadex appears to have an acceptable safety profile. Volatile agent such as sevoflurane seems not to influence the sugammadex ability to reverse the rocuronium neuromuscular blockade.
Androstanols ; gamma-Cyclodextrins ; Korea ; Methyl Ethers ; Neuromuscular Blockade ; Recurrence

BACKGROUND: The requisite anesthetic concentration of sevoflurane required to obtain adequate sedation when sufficient analgesics are supplied has not been determined. The purpose of this study was to determine the requisite age-associated concentration of sevoflurane to obtain an adequate level of anesthesia during combined epidural-general anesthesia by bispectral index (BIS) monitoring. METHODS: Twenty-seven elective abdominal surgery patients (American Society of Anesthesiologists physical status I-II) were enrolled. The patients were divided into two groups of more or less than 60 years of age. We investigated the concentration of sevoflurane required to obtain an adequate sedation level during combined epidural-general anesthesia, maintaining the BIS value between 40 and 60. RESULTS: The requisite sevoflurane concentration required to keep the BIS value at 40-60 was not stable during surgery. In the younger group, the maximum concentration of sevoflurane needed during surgery was 1.95 +/- 0.14 (95% confidence interval: 1.87-2.10) vol%, while it was 1.54 +/- 0.44 (95% confidence interval: 1.27-1.80) vol% in the older group (P < 0.01). CONCLUSIONS: The requisite concentration of sevoflurane required with combined epidural-general anesthesia was 2.5 vol% for the younger group and 2.0 vol% for the older group as determined by BIS monitoring. We believe that these percentages are sufficient to avoid awareness during surgery with adequate analgesia.
Analgesia ; Analgesics ; Anesthesia ; Anesthesia, Epidural ; Anesthetics, Inhalation ; Humans ; Methyl Ethers

BACKGROUND: As the wound healing is a multi-factorial process, the anesthetic agent and the duration of its exposure may influence the healing process after surgery. This study investigated the effect of anesthetic agents and duration of its exposure on the wound healing process after operation. METHODS: Total 32 rats weighing 200-300 g were randomly allocated to one of eight groups according to the exposure time (1, 2, 4, 8 hours) of sevoflurane or propofol (n = 4 each). After wounding under the each anesthetic, anesthesia was maintained for 1, 2, 4 and 8 hours in each group. We compared the skin blood flow around the wound and the wound size at baseline, 3 days, and 7 days postoperatively. RESULTS: In sevoflurane group, short exposure group (1, 2 hours) showed higher wound blood flow than long exposure (4, 8 hours) at 3 days after wounding (P < 0.05), but not at 7 days after wounding. For the wound size, there was no difference at 3 days after wounding in sevoflurane group, but 8 hours exposure group had the largest wound at 7 days after wounding. In propofol group, wound blood flow showed no difference at 3 days after wounding, but that of 4, 8 hours exposure group was higher than 2 hours exposure group at 7 days after wounding. There was no difference in wound size in propofol group. CONCLUSIONS: This study implicates that sevoflurane might influence the wound healing process more prominently than propofol according to the duration of exposure time.
Anesthesia ; Anesthetics ; Animals ; Methyl Ethers ; Propofol ; Rats ; Skin ; Wound Healing