High serum interleukin-6 level is associated with increased risk of delirium in elderly patients after noncardiac surgery: a prospective cohort study.

BACKGROUND: The relationship between inflammation and delirium remains to be determined. The purposes of this study were to investigate the association between serum interleukin-6 levels and the occurrence of delirium in elderly patients after major noncardiac surgery. METHODS: A total of 338 elderly patients (60 years of age and over) undergoing major noncardiac surgery were enrolled. Blood samples were obtained before anesthesia and in the first postoperative morning and serum interleukin-6 concentrations were measured. Delirium was assessed twice daily by the confusion assessment method for the Intensive Care Unit during the first three postoperative days. Survival analyses were performed to assess the relationship between the serum IL-6 level and the occurrence of postoperative delirium. RESULTS: Postoperative delirium occurred in 14.8% (50 of 338) of patients. High serum interleukin-6 levelsafter surgery were significantly associated with increased risk of the occurrence of postoperative delirium (hazard ratio 1.514, 95% confidence interval 1.155-1.985, P = 0.003). Other independent predictors of delirium included increasing age, poor preoperative New York Heart Association classification, low preoperative Mini-Mental State Examination score, and high total postoperative Visual Analogue Scale pain score. Patients who developed delirium had a prolonged hospital stay after surgery. CONCLUSIONS: Delirium is a frequent complication in elderly patients after noncardiac surgery. High serum interleukin-6 level after surgery is associated with increased risk of the occurrence of postoperative delirium.

Serum proteomics of early postoperative cognitive dysfunction in elderly patients.

BACKGROUND: Studies on postoperative cognitive dysfunction (POCD) have attracted extensive attention and achieved significant progress. However, the diagnosis of POCD is not very satisfactory as no specific biomarkers have been classified. The aim of the present study was to evaluate differences in serum protein composition between POCD and Non-POCD patients, identify potential biomarkers associated with early POCD, and study the mechanism underlying POCD. METHODS: Sixty-eight elderly patients (age ≥ 65 years) received isoflurane inhalation anesthesia for arthroplasty surgeries. One day before and seven days after the surgery, these patients were subjected to a neuropsychological test and venous blood sample collection. Postoperative cognitive dysfunction was determined using Z test scores. Based on the results, the patients were divided into POCD and non-POCD groups. Twenty-five randomly chosen blood samples obtained seven days after the surgery from each group were analyzed on a Bruker ultraFlex(TM) time of flight (TOF)/TOF mass spectrophotometer. The resulting peptide fingerprints were compared with those from the pre-surgery samples to identify differences in serum protein composition. The model designed to distinguish between a non-POCD group and a POCD group were established and validated. Three proteins with the most significant changes were selected for further characterization. RESULTS: Thirty-three cases were diagnosed as POCD. Using the Clinprotools software, 58 polypeptides were found to display differential expression (P < 0.05). Using a support vector algorithm method, seven differential peaks were isolated to establish a diagnostic model to distinguish POCD patients from normal individuals. The prediction rate and recognition rate were 96.89% and 100%, respectively. Validation of this model showed that the accuracy rates were 100% and 85% using samples from the POCD and non-POCD groups, respectively. Protein analysis also led to the identification of fibrinopeptide A (FPA) as a potential biomarker for POCD. CONCLUSIONS: Arthroplastic surgery under isoflurane inhalation anesthesia causes differential serum protein expression in elderly patients. These differentially expressed proteins may contribute to the diagnosis of early POCD, which may provide a basis for identifying the underlying mechanism of POCD development.

A new ß-glucosidase producing yeast for lower-cost cellulosic ethanol production from xylose-extracted corncob residues by simultaneous saccharification and fermentation.

This study reports a new yeast strain of Clavispora NRRL Y-50464 that is able to utilize cellobiose as sole source of carbon and produce sufficient native ß-glucosidase enzyme activity for cellulosic ethanol production using SSF. In addition, this yeast is tolerant to the major inhibitors derived from lignocellulosic biomass pre-treatment such as 2-furaldehyde (furfural) and 5-(hydroxymethyl)-2-furaldehyde (HMF), and converted furfural into furan methanol in less than 12h and HMF into furan-2,5-dimethanol within 24h in the presence of 15 mM each of furfural and HMF. Using xylose-extracted corncob residue as cellulosic feedstock, an ethanol production of 23 g/l was obtained using 25% solids loading at 37 °C by SSF without addition of exogenous ß-glucosidase. Development of this yeast aids renewable biofuels development efforts for economic consolidated SSF bio-processing.

[Effect of fascia iliaca compartment block with ropivacaine on early analgesia in children with development dislocation of the hip received salter arthroplasty treatment].

OBJECTIVE: To observe the efficacy and safety of fascia iliaca compartment block (FICB) with 0.2% ropivacaine in the early analgesia of children with development dislocation of the hip (DDH) undergoing Salter arthroplasty. METHODS: Approved by the hospital ethics committee, a total of 64 DDH children were divided randomly into 2 groups: group F (FICB with ropivacaine 0.2%, 1 ml/kg, max. 30 ml) and group C (FICB with 0.9% normal saline 1 ml/kg, max. 30 ml). The intra-operative doses of fentanyl, PACU (post-anesthesia care unit), CRIES pain score at 1, 4 and 24 h postoperatively, patient satisfaction score and side effects were recorded. RESULTS: The intra-operative doses of fentanyl and PACU were lower. Pain scores at 1, 4 and 24 h postoperatively were lower. And the patient satisfaction score was significantly higher in the FICB group. CONCLUSION: The administration of ropivacaine (0.2%) for FICB in the early analgesia of DDH children has the advantages of safety, precision, long-lasting and convenience.

[Comparing the analgesic efficacy of continuous femoral nerve blockade and continuous intravenous analgesia after total knee arthroplasty].

OBJECTIVE: To compare the analgesic efficacy of continuous femoral nerve blockade (CFNB) and continuous intravenous analgesia (CIA) after total knee arthroplasty (TKA). METHODS: 126 patients undergoing TKA under combined epidural-spinal anesthesia were randomized to receive either a femoral infusion of ropivacaine 0.2% (median infusion rate 5 ml/h) (n = 63) or an intravenous infusion of fentanyl 30 µg/kg (2 ml/h) (n = 63). Adjuvant analgesics were oral celebrex or IM pethidine. In the CFNB group, CFNB was established before combined epidural-spinal anesthesia and 20 ml 0.5%ropivacaine was infused through the catheter placed near femoral nerve. Visual analogue scale (VAS) scores were assessed at rest and on passive mobilization by acute pain service blinded to analgesic treatment. Nausea and vomiting, dizziness, satisfaction and other side-effects were assessed postoperatively. RESULTS: There was significantly less VAS scores in the CFNB group comparing the CIA group at rest 4, 8, 12, 16, 24, 36, 48 h after surgery (P < 0.01). A significant difference in VAS scores was found in CFNB group vs CIA group on passive mobilization 24, 36, 48 h after operation (P < 0.01). There was significantly less dizziness, nausea and vomiting in the CFNB group (P < 0.01). Patient satisfaction was higher in the CFNB group (92.1%) than the CIA group (20.6%) (P < 0.01). CONCLUSION: CFNA with ropivacaine 0.2% is more effective in controlling postoperative pain than CIA and CFNB is an effective regional component of a multimodal analgesic strategy after TKA.

[Ropivacaine volume for ultrasound-guided retrograde infraclavicular brachial plexus block].

OBJECTIVE: The aim of this study was to determine the medium effective volume required to produce an effective retrograde infraclavicular block using an ultrasound (US)-guided technique. METHODS: Thirty adults undergoing elective upper limb surgery received a US-guided retrograde infraclavicular block. The initial concentration of 0.5% ropivacaine injected was 30 ml, which was subsequently varied at a ratio of 1:1.2 for each consecutive patient according to the response of the previous patient. The medium effective volume (EV50) was determined using the Dixon and Massey up-and-down method. The effective volume in 95% of patients (EV95) was calculated using probit regression. RESULTS: The medium effective volume and calculated effective volume in 50% and 95% of patients were 23.6 ml (95% confidence interval, 21.3-26.2 ml) and 32.3 ml, respectively. No patient required a general anesthesia. CONCLUSION: The appropriate volume of 0.5% ropivacaine required for US-guided retrograde infraclavicular block was 30 ml in clinical practice.

[Effects of different doses and concentrations of ropivacaine in axillary brachial plexus block].

OBJECTIVE: To evaluate clinic pharmacodynamics of ropivacaine hydrochloride, a new long-acting amide type local anaesthetic, in Chinese patients undergoing neurolysis and tendolysis of forearm through axillary brachial plexus block. METHODS: Two hundred ASAI-II persons, aged 18-65,weighing 60-75 kg, undergoing neurolysis and tendolysis of forearm under axillary brachial plexus block were randomly assigned to 4 equal groups to received ropivacaine of the doses of 1.00 mg/kg (Group I), 1.25 mg/kg (Group II), 1.50 mg/kg (Group III), and 2.00 mg/kg (Group IV). Each group was subdivided into 5 equal subgroups according to the concentrations (0.15%, 0.20%, 0.25%, 0.30%, and 0.35%). The effects were analyzed. Results There was no significant difference in starting time, consummating time, and persisting time of sensory and motor nerve block between Group I and Group II (all P > 0.05). The starting time and consummating time of Group III and Group IV were all significantly shorter than those of Group I (all P < 0.05), and the persisting times of Groups III and IV were all significantly longer than those of Group I (P < 0.05). 90 minutes after brachial plexus block the degrees of muscle strength Groups I and II were M1 and M2 respectively, hence, the sensory and motor nerves block was in dissociation. When motor never block was above M3 and M4 the interval of brachial plexus block was 55 min and 27 min in Group III and Group IV respectively. CONCLUSION: Sensory and motor never can be blocked perfectly when the dose of ropivacaine is between 1.5 mg/kg and 2.0 mg/kg and the concentration is between 0.30%-0.35%. When the doses of ropivacaine is 1.25 mg/kg and the concentration is 0.20%-0.25% the starting and consummating time are longer and persisting time is shorter. When the doses of ropivacaine is 1.00 mg/kg and the concentration is 0.15%-0.20% the starting and consummating time are longer and only satisfies external debridement and suture without tourniquets.

Enhanced L-(+)-lactic acid production by an adapted strain of Rhizopus oryzae using corncob hydrolysate.

Corncob is an economic feedstock and more than 20 million tons of corncobs are produced annually in China. Abundant xylose can be potentially converted from the large amount of hemicellulosic materials in corncobs, which makes the crop residue an attractive alternative substrate for a value-added production of a variety of bioproducts. Lactic acid can be used as a precursor for poly-lactic acid production. Although current industrial lactic acid is produced by lactic acid bacteria using enriched medium, production by Rhizopus oryzae is preferred due to its exclusive formation of the L-isomer and a simple nutrition requirement by the fungus. Production of L-(+)-lactic acid by R. oryzae using xylose has been reported; however, its yield and conversion rate are poor compared with that of using glucose. In this study, we report an adapted R. oryzae strain HZS6 that significantly improved efficiency of substrate utilization and enhanced production of L-(+)-lactic acid from corncob hydrolysate. It increased L-(+)-lactic acid final concentration, yield, and volumetric productivity more than twofold compared with its parental strain. The optimized growth and fermentation conditions for Strain HZS6 were defined.

[Enzymatic hydrolysis of corn cob residues from furfural production].

The effect of pretreatment, enzyme loading, substrate concentration and reaction time on enzymatic hydrolysis of corn cob residues from furfural production was studied, and was compared with dilute acid pretreated corn cob. The result shows that the corn cob residues from furfural production couldn't be used directly due to higher acidity and inhibitor such as furfural etc. The enzymatic hydrolysis of the corn cob residues could be enhanced by water of Ca(OH)2 pretreatment. The best condition of corn cob residues after washed is 20 FPU/g substrate, 1:9 (substrate: buffer). The concentration and productivity of reducing sugar was 35 g/L and 30% at 48 h, and the conversion of cellulose was 61%.

Crystallization of oxytetracycline from fermentation waste liquor: influence of biopolymer impurities.

Organic impurities in the fermentation broth of antibiotic production impose great difficulties in the crystallization and recovery of antibiotics from the concentrated waste liquor. In the present laboratory study, the inhibitory effect of biopolymers on antibiotic crystallization was investigated using oxytetracycline (OTC) as the model antibiotic. Organic impurities separated from actual OTC fermentation waste liquor by ultrafiltration were dosed into a pure OTC solution at various concentrations. The results demonstrated that small organic molecules with an apparent molecular weight (AMW) of below 10,000 Da did not affect OTC crystallization significantly. However, large biopolymers, especially polysaccharides, in the fermentation waste caused severe retardation of crystal growth and considerable deterioration in the purity of the OTC crystallized. Atomic force microscopy (AFM) revealed that OTC nuclei formed in the solution attached to the surfaces of large organic molecules, probably polysaccharides, instead of being surrounded by proteins as previously thought. It is proposed that the attachment of OTC nuclei to biopolymers would prevent OTC from rapid crystallization, resulting in a high OTC residue in the aqueous phase. In addition, the adsorption of OTC clusters onto biopolymers would destabilize the colloidal system of organic macromolecules and promote particle flocculation. OTC crystallization would therefore take place with the precipitation of abundant organic impurities. Hence, the removal of polysaccharides and other biopolymers by ultrafiltration can be an effective means of improving the recovery of OTC and similar antibiotics by crystallization from the fermentation waste.