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J Tang

Publications and source records attributed to J Tang.

At least 37 records · Page 2Linked to original sources
PubMed2001

Polyoxometalate HIV-1 protease inhibitors. A new mode of protease inhibition.

Nb-containing polyoxometalates (POMs) of the Wells-Dawson class inhibit HIV-1 protease (HIV-1P) by a new mode based on kinetics, binding, and molecular modeling studies. Reaction of alpha(1)-K(9)Li[P(2)W(17)O(61)] or alpha(2)-K(10)[P(2)W(17)O(61)] with aqueous H(2)O(2) solutions of K(7)H[Nb(6)O(19)] followed by treatment with HCl and KCl and then crystallization affords the complexes alpha(1)-K(7)[P(2)W(17)(NbO(2))O(61)] (alpha(1)()1) and alpha(2)-K(7)[P(2)W(17)(NbO(2))O(61)] (alpha(2)()1) in 63 and 86% isolated yields, respectively. Thermolysis of the crude peroxoniobium compounds (72-96 h in refluxing H(2)O) prior to treatment with KCl converts the peroxoniobium compounds to the corresponding polyoxometalates (POMs), alpha(1)-K(7)[P(2)W(17)NbO(62)] (alpha(1)()2) and alpha(2)-K(7)[P(2)W(17)NbO(62)] (alpha(2)()2), in moderate yields (66 and 52%, respectively). The identity and high purity of all four compounds were confirmed by (31)P NMR and (183)W NMR. The acid-induced dimerization of the oxo complexes differentiates sterically between the cap (alpha(2)) site and the belt (alpha(1)) site in the Wells-Dawson structure (alpha(2)()2 dimerizes in high yield; alpha(1)()2 does not). All four POMs exhibit high activity in cell culture against HIV-1 (EC(50) values of 0.17-0.83 microM), are minimally toxic (IC(50) values of 50 to >100 microM), and selectively inhibit purified HIV-1 protease (HIV-1P) (IC(50) values for alpha(1)()1, alpha(2)()1, alpha(1)()2, and alpha(2)()2 of 2.0, 1.2, 1.5, and 1.8 microM, respectively). Thus, theoretical, binding, and kinetics studies of the POM/HIV-1P interaction(s) were conducted. Parameters for [P(2)W(17)NbO(62)](7)(-) were determined for the Kollman all-atom (KAA) force field in Sybyl 6.2. Charges for the POM were obtained from natural population analysis (NPA) at the HF/LANL2DZ level of theory. AutoDock 2.2 was used to explore possible binding locations for the POM with HIV-1P. These computational studies strongly suggest that the POMs function not by binding to the active site of HIV-1P, the mode of inhibition of all other HIV-1P protease inhibitors, but by binding to a cationic pocket on the "hinge" region of the flaps covering the active site (2 POMs and cationic pockets per active homodimer of HIV-1P). The kinetics and binding studies, conducted after the molecular modeling, are both in remarkable agreement with the modeling results: 2 POMs bind per HIV-1P homodimer with high affinities (K(i) = 1.1 +/- 0.5 and 4.1 +/- 1.8 nM in 0.1 and 1.0 M NaCl, respectively) and inhibition is noncompetitive (k(cat) but not K(m) is affected by the POM concentration).

Anti-HIV Agents↗
PubMed2001

Near-infrared photo-excited emission from tissues treated at different temperature levels.

BACKGROUND AND OBJECTIVE: There is a lack of methods to evaluate the extent of thermal treatment of biological tissue. The intensity of the near-infrared (NIR) emission photo-excitation was investigated from tissue undergoing different levels of heat treatment. STUDY DESIGN/MATERIALS AND METHODS: Chicken muscle was heated in an oven at different temperature levels ranging from 40 degrees C until burn-off. The spectral emission intensity from these heat-treated tissues was measured with a CCD camera and the intensity was calculated. RESULTS: The emission intensity increased proportionally with respect to the extent of treatment temperature until burning. Linear relationships between treatment temperature and the emission intensity from tissue samples were found in three temperature ranges: from 40 to 160 degrees C, from 165 to 220 degrees C, and from 225 to 250 degrees C. CONCLUSIONS: The change in tissue damage after heat treatment could be detected by measuring the NIR emission intensity from the thermally damaged tissues.

Animals↗
PubMed2001

Age-related RhoA expression in blood vessels of rats.

Aging is a major risk factor for the development of vascular diseases that lead to stroke and heart failure. Several cellular factors such as cell adhesion, motility, contractile response, and cytokinesis are involved in the aging process. RhoA, a member of the Rho family, plays a primary role in the regulation of these cellular factors. This study aims to investigate whether RhoA is involved in these age-related responses to vascular change. We found that in older rats (19 months ole), RhoA mRNA increased 1.9-fold in the aortic arteries and 2.4-fold in the basilar arteries compared to the younger rats (2 months old). Membrane binding, but not cytosol RhoA, levels were found to significantly increase in the aortic and basilar arteries with age, which suggests that RhoA activity increases in older rats. Staining of RhoA increased markedly with age in both the medial and endothelial layers of the collected aortic and basilar arteries. These results show that RhoA expression and activity in the aortic and basilar arteries increased as a function of age, thereby suggesting that RhoA might be altered in the vascular response change of aged rats.

Aging↗
PubMed2001

Re-evaluation of cellulose acetate polymer: angiographic findings and histological studies.

BACKGROUND: Cellulose acetate polymer (CAP) is a new liquid embolic material that has been used experimentally in intravascular treatment of intracranial aneurysms. But this compound is still controversial in some aspects such as safety, efficiency, and histological changes. In this study, we re-evaluated the material with regard to intravascular treatment of aneurysms. METHODS: The carotid arteries of rats and experimental aneurysms in canines were embolized with CAP. The effects of CAP were evaluated according to angiographic and histological results. RESULTS: A strong chemo-corrosive effect was observed. This led to severe damage to vessels and rupture of two thrombosed canine aneurysm models. There were significant technical difficulties including out-flow of CAP and a high rate of occlusion of the parent arteries. CONCLUSIONS: We conclude that currently CAP is not an ideal embolic material for intracranial aneurysms. Further tests and improvements are needed before it can be widely used clinically.

Angiography, Digital Subtraction↗
PubMed2001

Novel alleles at the lymphotoxin alpha (LTalpha) locus mark extended HLA haplotypes in native Africans.

Genetic variations at the closely related tumor necrosis factor alpha (TNFalpha or TNF) and lymphotoxin alpha (LTalpha, formerly TNFbeta) loci have been well documented in various human populations, and several haplotypes spanning the MHC class I and class II loci are known to carry specific TNF alleles. Genotyping of the TNFc microsatellite within the first intron of LTalpha in 285 Rwandans and 319 Zambians revealed two predominant alleles, c1 at frequencies of 0.598 and 0.683 and c2 at 0.384 and 0.307, respectively. Overall, the distribution of TNFc genotypes containing the major alleles conformed well to the Hardy-Weinberg equilibrium in both cohorts. Two previously unrecognized minor TNFc alleles were also detected: the first, designated c0, was found in 10 native Africans and was the only allele present in 10 chimpanzees; the second, designated c3, was seen in 6 other African patients. Further genotyping at loci for HLA class I, class II, and for transporters associated with antigen processing, subunit 1 (TAP1) in those 16 individuals suggested a tight, stable extended haplotype involving c0 and 26Asn (LTalpha)-TNF3 (TNF promoter -238A and -308G)-DRB1*1503-DQB1*0602-TAP1.2 (333Val)-TAP1.4 (637Gly). The c3 allele was observed on another extended haplotype with 26Thr (LTalpha)-TNF1 (TNF promoter -238G and -308G)-DQB1*0102-DQB1*0501-TAP1*0101 (333Ile and 637Asp). The c3-tagged haplotype further extended to Cw*15 at the HLA class I C locus, but no specific A or B alleles could be unambiguously assigned. Positive associations between c2 homozygosity and HIV-1 seronegative status in both Rwandans and Zambians (odds ratio = 2.03 and 2.00, p = 0.04 and 0.07, respectively) had little effect on the haplotype assignments. These findings suggest a preferential expansion of the human TNFc dinucleotide (CT/AG) repeat sequence and further imply the existence of two extended MHC lineages that have not been disrupted by recombinations.

Africa↗
PubMed2001

TAPI polymorphisms in several human ethnic groups: characteristics, evolution, and genotyping strategies.

Genetic variations in the locus encoding the transporter associated with antigen processing, subunit 1 (TAP1), were systematically studied using samples from Caucasians, Africans, Brazilians, and compared with data from chimpanzees. PCR-amplified genomic sequences corresponding to the 11 exons were analyzed by single-strand conformation polymorphism (SSCP) and sequencing. Six nonsynonymous and 2 synonymous single nucleotide polymorphisms (SNPs) were found to be common in one ethnic group or another, and they involved codons 254 (Gly-GGC/Gly-GGT) in exon 3, 333 (Ile-ATC/Val-GTC) in exon 4, 370 (Ala-GCT/Val-GTT) in exon 5, 458 (Val-GTG/Leu-TTG) in exon 6, 518 (Val-GTC/Ile-ATC) in exon 7, 637 (Asp-GAC/Gly-GGC), 648 (Arg-CGA/Gln-CAA) and 661 (Pro-CCG/Pro-CCA) in exon 10. At each SNP site the sequence listed first was predominant in all ethnic groups. Several SNPs segregated on the same chromosome regardless of populations and species. Together, the SNPs produced 5 major human TAP1 alleles, 4 of which matched the officially recognized alleles *0101, *02011, *0301, and *0401; the 5th allele differed from each of those by at least 4 SNPs. Overall, TAP1*0101 was the predominant allele in all ethnic groups, with frequencies ranging from 0.667 in Zambians to 0.808 in US Caucasians. The TAP1*0401 frequency showed the greatest difference between Africans (0.221-0.254) and Caucasians (0.033), with Brazilians (0.058) fitting in the middle. Consistent with earlier work based on Caucasians and gorillas, *0101 appeared to be the newest human TAP1 allele, suggesting a dramatic spread of *0101 into all human populations examined. Characterization of TAP1 polymorphisms allowed the design of a PCR-based genotyping scheme that targeted 7 SNP sites and required 2 separate genotyping techniques.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

Preoperative high-dose chemotherapy with peripheral blood stem cell support as a primary management of locally advanced breast cancer.

Locally advanced breast cancer (LABC) has a poor prognosis with a high risk of local recurrence and distant metastasis. Preoperative combined chemotherapy with or without granulocyte colony-stimulating factor (G-CSF) support does not improve the long-term survival rate. In our report, two patients with LABC received preoperative high-dose chemotherapy with peripheral blood stem cell support (HDC/PBSCs). Prior to high-dose chemotherapy with peripheral blood stem cell support, they both received induction chemotherapy of cyclophosphamide, epirubicin and 5-fluorouracil (FEC) for two cycles which resulted in a partial response. PBSC mobilization and collection were carried out following the second cycle of induction chemotherapy followed by G-CSF. High-dose cyclophosphamide (2500 mg/m2), carboplatin (600 mg/m2) and etoposide (600 mg/m2) were administered with PBSC support. A radical mastectomy was performed followed by adjuvant chemotherapy with FEC regimen for four cycles, followed by local irradiation, and endocrine therapy with tamoxifen. Both patients achieved a remarkable response in the primary lesion after HDC/PBSCs and tolerated the whole treatment well. Preoperative HDC/PBSCs as a new strategy in the treatment of LABC seems practical but it needs to be studied more deeply.

Adult↗
PubMed2001

Genotyping TAP2 variants in North American Caucasians, Brazilians, and Africans.

The protein forms of transporter associated with antigen processing, subunit 2 (TAP2), differ either by amino acid substitutions (Thr374Ala, Ile379Val, Ile467Val, Thr565Ala, Val577Met, Cys651Arg, and Ala665Thr) or by a truncation (Gln687Stop) of 17 amino acid residues at the C-terminus. Nonsynonymous single nucleotide polymorphisms (N-SNPs) causing these amino acid variations except 577Val were detected in genomic DNA samples from North American Caucasians (n = 76), Brazilians (n = 148), Rwandans (n = 285), and Zambians (n = 117). Exclusive (100%) and nearly exclusive (>95%) linkage disequilibrium was seen with a number of N-SNPs. The average heterozygosity at any given dimorphic site ranged from 7.3% to 44.6%, and at least four N-SNPs showed clear population specificity. N-SNP combinations alone led to the identification of 16 relatively common alleles, which appeared to form at least three lineages. Further analyses of 101 cDNA samples from Brazilians detected nine expressed TAP2 alleles, four of which matched the official assignments. Genetic complexity at the TAP2 locus was further enhanced by two out of five synonymous SNPs (S-SNPs), especially the GGT386GGG (Gly) that had similar heterozygosity rates in Caucasians (28.9%), Rwandans (33.3%), and Zambians (33.3%). Overall, distribution of both synonymous and nonsynonymous SNPs in the various ethnic groups examined here conformed well to the Hardy-Weinberg equilibrium, and between 57.9% and 77.0% of subjects in each ethnic group were heterozygous with two TAP2 alleles predicted to differ by at least one amino acid residue. Such complexity of TAP2 polymorphisms, in the form of SNPs as well as alleles, is likely to complicate the analyses of disease associations and haplotype structures in the HLA class II region.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

Interleukin 10 polymorphisms as predictors of sustained response in antiviral therapy for chronic hepatitis C infection.

Host genetic factors have been reported to influence the natural history of hepatitis C virus (HCV) infection. We examined whether variation in interleukin 10 (IL-10) and tumor necrosis factor alpha (TNF-alpha) genes would predict the likelihood of sustained response to antiviral therapy. Single nucleotide polymorphisms (SNPs) and microsatellites at two loci encoding the cytokines IL-10 and TNF-alpha were determined by polymerase chain reaction (PCR)-based techniques. Their relationship to the outcome of antiviral therapy for chronic HCV infection was studied in 49 white patients who had a virologically sustained response (SR) and in 55 white nonresponders (NR) to a combination of interferon alfa-2b and ribavirin (IFN + R). Several IL-10 variants were more frequent among SRs compared with NRs. Carriage of the -592A or the -819T SNP was associated with SR (odds ratio [OR] = 2.2; P =.016). The -592A/A and the exclusively linked -819T/T genotypes were also associated with SR (OR = 16.6; P =.013 for either). The haplotype consisting of the 108-bp IL-10.R microsatellite and -3575T, -2763C, -1082A, -819T, -592A was also associated with SR (OR = 2.65; P =.01). Stratification for viral genotype, baseline viral RNA concentration, and histologic status identified homozygosity for the haplotype as the principal determinant: all 5 homozygous individuals achieved SR (OR(crude) = 13.7; P =.025; stratified ORs = 1.9-7.0), whereas heterozygotes differed only slightly from wild-type carriers. In contrast, TNF alleles defined by promoter sequences -238G/A and -308G/A were approximately equally distributed among SR and NR. In conclusion, homozygosity for -592A, -819T or the extended haplotype (108bp) - (-2575T) - (-2763C) - (-1082A) - (-819T) - (-592A) is associated with SR to IFN + R.

Alleles↗
PubMed2001

Differences between subcultures of the Mesorhizobium loti type strain from different culture collections.

Because of differences in the reported 16S rRNA gene sequence of the Mesorhizobium loti type strain available from different culture collections, we collected different subcultures of this strain and compared them by 16S rDNA sequencing, SDS-PAGE of whole-cell protein extracts and RAPD-PCR. Our results indicate that the 16S rDNA sequence differences can be explained by the presence of two different organisms in one of the subcultures. In addition, even for subcultures of the type strain that had identical 16S rDNA sequences, small differences could be observed in the protein profiles and in the RAPD-PCR patterns. These latter observations indicate that maintenance procedures necessary for long-term preservation by freeze-drying can cause subcultures of the same original strain to undergo changes, effectively leading to different fingerprints even though 16S rDNA sequences remain identical.

DNA Fingerprinting↗
PubMed2001

Lower BMI cut-off value to define obesity in Hong Kong Chinese: an analysis based on body fat assessment by bioelectrical impedance.

There is increasing evidence suggesting that the cut-off values for defining obesity used in the Western countries cannot be readily applied to Asians, who often have smaller body frames than Caucasians. We examined the BMI and body fat (BF) as measured by bioelectrical impedance in 5153 Hong Kong Chinese subjects. We aimed to assess the optimal BMI reflecting obesity as defined by abnormal BF in Hong Kong Chinese. Receiver operating characteristic curve (ROC) analysis was used to assess the optimal BMI predicting BF at different levels. The mean age and SD of the 5153 subjects (3734 women and 1419 men) was 51.5 (SD 16.3) years (range: 18.0-89.5 years, median: 50.7 years). Age-adjusted partial correlation (r) between BMI and BF in women and men were 0.899 (P < 0.001) and 0.818 (P < 0.001) respectively. Using ROC analysis, the BMI corresponding to the conventional upper limit of normal BF was 22.5-23.1 kg/m(2), and the BMI corresponding to the 90 percentiles of BF was 25.4-26.1 kg/m(2). Despite similar body fat contents, the BMI cut-off value used to define obesity in Hong Kong Chinese should be lower as compared to Caucasians. We suggest a BMI of 23 kg/m(2) and 26 kg/m(2) as the cut-off values to define overweight and obesity respectively in Hong Kong Chinese.

Absorptiometry, Photon↗
PubMed2001

Helper virus-free HSV-1 vectors packaged both in the presence of VSV G protein and in the absence of HSV-1 glycoprotein B support gene transfer into neurons in the rat striatum.

Herpes simplex virus (HSV-1) vectors have potential for gene transfer into quiescent cells, but the gene transfer process could be more efficient. In other vector systems, both the titers and the efficiency of gene transfer have been enhanced by pseudotyping the vector particles with vesicular stomatitis virus (VSV) G protein. In this report, we pseudotyped helper virus-free HSV-1 plasmid vectors with VSV G protein. Packaging was performed in the presence of both VSV G protein and a deletion in an essential HSV-1 glycoprotein, gB. The resulting vector stocks supported gene transfer into both fibroblast and neuronal cell lines. VSV G protein was required for gene transfer because preincubation of these vector stocks with antibodies directed against either VSV G protein or VSV reduced the titer to undetectable levels. Although the titers were lower than those obtained using the unmodified vector system, the titers were not increased by use of chimeric proteins that contain the extracellular domain of VSV G protein and the transmembrane and/or cytoplasmic domains of specific HSV-1 glycoproteins. Also, the titers were not increased by performing the packaging in the presence of deletions in multiple HSV-1 glycoproteins. Nonetheless, pHSVlac pseudotyped with VSV G protein supported gene transfer into striatal neurons in the rat brain. Thus, HSV-1 vectors pseudotyped with VSV G protein may be useful for specific gene transfer studies.

Animals↗
PubMed2001

Effects of repeated oral postnatal exposure to chlorpyrifos on open-field behavior in juvenile rats.

Organophosphorus (OP) insecticides have the potential to cause behavioral effects in children. This study was designed to determine if repeated oral exposure of preweanling rats to chlorpyrifos would produce behavioral changes at both pre- and postweanling ages. Treatment occurred every second day beginning on post-natal day (PND) 1, and continued through PND 21. The rats received one of the following regimens: a low-dosage (3 mg/kg) from PND 1-21; a medium dosage (mg/kg from PND 1-5, and then 6 mg/kg from PND 7-21; or a high-dosage schedule of 3 mg/kg on PND 1-5, then 6 mg/kg from PND 7-13, and 12 mg/kg from PND 15-21. There were no differences in body weights among the control-, low-, and medium-dosage groups but the high-dosage group had significantly lower body weights on PND 13-21. An open field was used to measure locomotor activity on PND 10, 12, 14, 16, 18, 20, 25, and 30. There were no differences in locomotor activity levels or treatment effects between males and females. On PND 10, 12, 14, 16, 18, and 20 there was no effect on locomotor activity with any dosage. On days 25 and 30, locomotor activity was significantly decreased with the medium- and high-dosage groups. Brain cholinesterase (ChE) inhibition was about 25-38% on PND 25 and 14-34% on PND 30. On PND 25 but not 30, lung and diaphragm ChE and serum butyrylcholinesterase (BChE), with the high-dosage animals, and heart ChE with the medium- and high-dosage groups were significantly inhibited. There was no significant inhibition of skeletal muscle ChE or serum acetylcholinesterase (AChE) on PND 25 and 30. These data suggest that early postnatal chlorpyrifos exposures will depress locomotor activity in juvenile rats, with the effects most pronounced after brain ChE activity has substantially recovered.

Acetylcholinesterase↗
PubMed2001

Fast-track office-based anesthesia: a comparison of propofol versus desflurane with antiemetic prophylaxis in spontaneously breathing patients.

IMPLICATIONS: Compared to propofol, maintenance of anesthesia with desflurane provided significantly better intraoperative conditions during office-based surgery. In addition, desflurane with routine antiemetic prophylaxis was associated with a faster early recovery and similar incidence of postoperative side effects.

Ambulatory Surgical Procedures↗
PubMed2001

Propacetamol versus ketorolac for treatment of acute postoperative pain after total hip or knee replacement.

We assessed the analgesic efficacy of IV propacetamol and ketorolac in a double-blinded, placebo-controlled study involving patients undergoing total hip or knee replacement procedures. On the first morning after major joint replacement surgery, 164 patients experiencing moderate-to-severe pain were randomly assigned to receive an IV infusion of propacetamol (2 g), ketorolac (15 or 30 mg), or placebo (saline). Patient-controlled analgesia with morphine was made available as a "rescue" analgesic on patient's request during the 6-h postdosing evaluation period. The median time to onset of analgesia with propacetamol (8 [95% confidence interval 6,10] min) was shorter than ketorolac 15 mg (14 [7,16] min), and placebo (16 [8; not estimable] min) although the differences did not reach statistical significance. However, compared with ketorolac 30 mg, propacetamol had a shorter duration of analgesia (3.5 [2;5.4] vs 6 [3.3; not estimable] h). Analysis of pain intensity and pain relief scores demonstrated that propacetamol produced a significantly greater improvement in pain relief than saline from 45 min until 5 h after the injection. Propacetamol was not significantly different from ketorolac 15 mg and 30 mg with respect to the main analgesic efficacy variables during the 6-h assessment period. The most frequently reported adverse event with propacetamol was injection site pain (28% vs 19% for ketorolac 15 mg, 29% for ketorolac 30 mg, and 10% for placebo, respectively). In conclusion, propacetamol (2 g IV) possesses a similar analgesic efficacy to ketorolac (15 or 30 mg IV) after total hip or knee replacement surgery.

Acetaminophen↗
PubMed2001

The effect of timing of dolasetron administration on its efficacy as a prophylactic antiemetic in the ambulatory setting.

UNLABELLED: Dolasetron (12.5 mg IV) is effective in both preventing and treating postoperative nausea and vomiting (PONV) after ambulatory surgery. However, the optimal timing of dolasetron administration and its effect on the patient's quality of life after discharge have not been established. One-hundred-five healthy, consenting women undergoing gynecologic laparoscopic procedures with a standardized general anesthetic technique were enrolled in this randomized, double-blinded study. Group 1 received dolasetron 12.5 mg IV 10-15 min before the induction of anesthesia; Group 2 received dolasetron 12.5 mg IV at the end of the laparoscopy (79 +/- 48 min later than Group 1); and Group 3 received dolasetron 12.5 mg IV at the end of anesthesia (93 +/- 52 min later than Group 1). The incidence of PONV, complete responses (defined as no emetic episodes and no rescue medication within the 24-h period after anesthesia), recovery profiles, and patient satisfaction were recorded. In the postanesthesia care unit and during the 24-h follow-up period, the incidence of nausea and vomiting, as well as the need for rescue antiemetics, did not differ significantly among the three groups. The percentages of patients with complete responses to the study drug within the first postoperative 24 h were also similar in all three groups (55%, 59%, and 52% for Groups 1, 2, and 3, respectively). The early and intermediate recovery profiles, including resumption of a normal diet and patient satisfaction with the control of PONV, were not different among the three study groups. Dolasetron 12.5 mg IV administered before the induction of anesthesia is as effective as dolasetron given at the end of laparoscopy or at the end of anesthesia in preventing PONV after outpatient laparoscopy. IMPLICATIONS: The timing of dolasetron administration appears to have little effect on its efficacy when administered as a prophylactic antiemetic in the ambulatory setting.

Adult↗
PubMed2001

The recovery of cognitive function after general anesthesia in elderly patients: a comparison of desflurane and sevoflurane.

UNLABELLED: We evaluated the cognitive recovery profiles in elderly patients after general anesthesia with desflurane or sevoflurane. After IRB approval, 70 ASA physical status I-III consenting elderly patients (> or =65 yr old) undergoing total knee or hip replacement procedures were randomly assigned to one of two general anesthetic groups. Propofol and fentanyl were administered for induction of anesthesia, followed by either desflurane 2%-4% or sevoflurane 1%-1.5% with nitrous oxide 65% in oxygen. The desflurane (2.5 +/- 0.6 MAC. h) and sevoflurane (2.7 +/- 0.5 MAC. h) concentrations were adjusted to maintain comparable depths of hypnosis using the electroencephalogram bispectral index monitor. The Mini-Mental State (MMS) test was used to assess cognitive function preoperatively and postoperatively at 1, 3, 6, and 24-h intervals. The use of desflurane was associated with a more rapid emergence from anesthesia (6.3 +/- 2.4 min versus 8.0 +/- 2.8 min) and a shorter length of stay in the postanesthesia care unit (213 +/- 66 min versus 241 +/- 87 min). However, there were no significant differences between the Desflurane and the Sevoflurane groups when the MMS scores were compared preoperatively, and postoperatively at 1, 3, 6, and 24 h. Compared with the preoperative (baseline) MMS scores, the values were significantly decreased at 1 h postoperatively (27.8 +/- 1.7 versus 29.5 +/- 0.5 in the Desflurane group, and 27.4 +/- 1.7 versus 29.2 +/- 1.0 in the Sevoflurane group, respectively). However, the MMS scores returned to preoperative baseline levels within 6 h after surgery. At 1 h and 3 h after surgery, 51% and 11% (versus 57% and 9%) of patients in the Desflurane (versus Sevoflurane) Group experienced cognitive impairment. In conclusion, desflurane is associated with a faster early recovery than sevoflurane after general anesthesia in elderly patients. However, recovery of cognitive function was similar after desflurane and sevoflurane-based anesthesia. IMPLICATIONS: Desflurane was associated with a faster early recovery than sevoflurane after general anesthesia in elderly patients. However, recovery of cognitive function was similar with both volatile anesthetics.

Aged↗