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1.
Poult Sci ; 98(11): 5525-5532, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31180123

ABSTRACT

Two experiments were conducted to evaluate 3 novel proteases in broilers. In experiment 1, 600 male, Cobb 500 broilers were allocated to 1 of 12 experimental diets (5 birds/pen and 10 replicates/diet). A control (C) diet was formulated to be adequate in all nutrients. Proteases 1, 2, or 3 were added to this diet at 3 doses (1x, 3x, or 9x) in a 3 × 3 factorial arrangement of treatments. The factorial was augmented with 2 treatments of phytase at 500 or 1,500 FTU/kg added to the C diet. In experiment 2, 2,050 male Ross 308 broilers were allocated to 1 of 10 experimental diets (25 birds/pen and 9 replicates/diet). A C diet was formulated to be adequate in all nutrients. Protease 1, 2, or 3 was then added to the C diet at 3 doses (1x, 2x, or 4x) in a 3 × 3 factorial arrangement of treatments plus the C. In experiment 1, birds fed phytase gained more (P < 0.05) than birds fed protease, but neither were different than birds fed the C. Supplementation of 9x dose of any protease resulted in a reduction (P < 0.05) in BWG when compared with birds fed 1x dose of protease or phytase at 500 or 1,500 FTU/kg. Feed conversion ratio was improved (P < 0.05) in birds fed phytase compared with birds fed the C diet. Nitrogen digestibility was greater (P < 0.05) in birds fed protease 1 when compared with birds fed protease 2. Birds fed the 1x dose of protease or 500 FTU/kg of phytase had a greater (P < 0.05) N digestibility than birds fed 3x dose of protease. In experiment 2, protease supplementation significantly reduced (P < 0.05) BWG when compared with birds fed the C from hatch to 35 D post-hatch. Protease supplementation did not improve broiler growth performance or N digestibility above that of a nutrient adequate control diet or a diet supplemented with 500 FTU/kg of phytase.


Subject(s)
6-Phytase/metabolism , Chickens/physiology , Dietary Proteins/metabolism , Digestion/drug effects , Peptide Hydrolases/metabolism , Age Factors , Animal Feed/analysis , Animal Nutritional Physiological Phenomena/drug effects , Animals , Chickens/growth & development , Diet/veterinary , Dietary Proteins/administration & dosage , Dietary Supplements/analysis , Dose-Response Relationship, Drug , Male , Nutrients/physiology , Peptide Hydrolases/administration & dosage , Random Allocation
2.
Poult Sci ; 97(6): 2123-2138, 2018 Jun 01.
Article in English | MEDLINE | ID: mdl-29608749

ABSTRACT

Three experiments were conducted to evaluate eight neutral and six acid proteases on growth performance and apparent ileal amino acid digestibility (AID) of poults (Experiment 1) or chicks (Experiments 2 and 3). Two basal diets were formulated: a nutrient adequate positive control (PC), which met or exceeded the nutrient requirements for poults (Experiment 1) or chicks (Experiments 2 and 3) and a negative control (NC) formulated to achieve 85% (Experiments 1 and 2) or 80% (Experiments 3) of the requirement for protein and amino acids. Phytase was included in all diets to provide 500 phytase units (FTU)/kg and xylanase was included in all diets to provide 10,000 (Experiments 1 and 2) or 16,000 (Experiments 3) xylanase units (BXU)/kg. Proteases were supplemented in the NC diet at an equivalent amount of enzyme protein to create 16 experimental diets. There were five birds/pen and 10 replicate pens per treatment in each experiment. In experiment 1, birds fed the PC diet gained more (P < 0.05) than birds fed the NC. There were no differences in growth performance in birds fed the PC or NC in experiments 2 or 3. In all three experiments, birds fed the NC supplemented with neutral protease 1 had reduced (P < 0.05) feed intake (FI) or body weight gain (BWG) and increased (P < 0.05) feed conversion ratio (FCR) compared with birds fed the NC. Birds fed the NC diet supplemented with neutral protease 3, 7 (Experiment 1), or acid protease 4 (Experiment 3) had increased (P < 0.05) FCR and birds fed neutral protease 6 (Experiment 2) had reduced (P < 0.05) BWG compared with birds fed the NC. Apparent ileal amino acid digestibility was improved (P < 0.05) with protease supplementation to the NC diets (Experiment 1 or 3), but this was dependent on the protease and the amino acid. In conclusion, novel protease supplementation improved AID of amino acids but this was not reflected in improvements in growth performance of poults or chicks.


Subject(s)
Amino Acids/metabolism , Aspartic Acid Proteases/metabolism , Chickens/physiology , Digestion/drug effects , Eating , Serine Proteases/metabolism , Turkeys/physiology , Animal Feed/analysis , Animal Nutritional Physiological Phenomena/drug effects , Animals , Aspartic Acid Proteases/administration & dosage , Chickens/growth & development , Diet/veterinary , Dietary Supplements/analysis , Ileum/physiology , Male , Random Allocation , Serine Proteases/administration & dosage , Turkeys/growth & development
3.
Br J Anaesth ; 108(5): 838-44, 2012 May.
Article in English | MEDLINE | ID: mdl-22369767

ABSTRACT

BACKGROUND: Photoplethysmographic pulse wave amplitude (PPGA) and heart rate (HR) can be used to measure cold, nociception-induced autonomic responses, or both. The aim of our study was to correlate the intensity of experimental pain to changes in physiological variables reflecting the autonomic nervous system response to pain. METHODS: PPGA, HR, and subjective measurements of pain intensity were measured in 29 healthy male volunteers during two heat stimuli (43°C and 48°C) and the cold pressor test (CPT). Surgical pleth index (SPI), autonomic nervous system state (ANSS), and ANSS index (ANSSi) were calculated using PPGA and HR. RESULTS: Pain intensity scores increased on the average by 1.6, 3.5, and 8.1 for the 43°C, 48°C, and CPT stimuli, respectively. The pain intensity scores for all three stimuli groups were significantly different from each other (P<0.001). All three stimuli changed HR, PPGA, SPI, ANSS, and ANSSi values significantly from their respective baseline values (P<0.001 for all). Heat stimuli-induced pain intensity did not correlate with the magnitude of the respective changes in HR, PPGA, SPI, ANSS, and ANSSi. CPT-induced pain intensity correlated with the magnitude of the respective changes in HR, PPGA, SPI, ANSS, and ANSSi. PPGA, ANSSi, ANSS, and SPI differentiated between heat and cold stimuli-induced pain. CONCLUSIONS: All three thermal stimuli produced a significant change in photoplethysmograph-derived parameters. All photoplethysmograph-derived parameters appear to be suitable to study autonomic nervous system activation.


Subject(s)
Autonomic Nervous System/physiopathology , Pain/physiopathology , Adolescent , Adult , Cold Temperature , Heart Rate/physiology , Hot Temperature , Humans , Male , Pain/diagnosis , Pain/etiology , Pain Measurement/methods , Photoplethysmography/methods , Young Adult
4.
Br J Anaesth ; 104(5): 587-95, 2010 May.
Article in English | MEDLINE | ID: mdl-20354006

ABSTRACT

BACKGROUND: Autonomic nervous system (ANS) sensitively responds to intraoperative stress. Several indices characterizing the state and responses of autonomic signs to nociceptive stimuli have been introduced. This study evaluated the behaviour of ANS descriptors after induction, before and during tracheal intubation, and during bilateral tonsillectomies after random and blinded unilateral infiltration of lidocaine 1% until emergence from anaesthesia. METHODS: Twelve patients undergoing bilateral tonsillectomy were anaesthetized with fentanyl and propofol (induction) and sevoflurane (maintenance). All patients were monitored throughout anaesthesia for middle finger temperature, non-invasive arterial pressure, heart rate (HR) and pulse rate (PR), state entropy (SE) and response entropy (RE), and surgical pleth index (SPI). New parameters complementing the above and characterizing the ANS state (ANSS) and responses are pulse-to-pulse interval (PPI), pulse plethysmographic amplitude (PPGA), ANSS, and an index based on maximal ANSS for the subject (ANSSI). Serial data were stored as 10 s averages into a laptop computer. RESULTS: Anaesthesia induction was associated with an increase in finger temperature to >30 degrees C within 10 min, whereas PPGA increased to their maximum levels within 5 min. Laryngoscopy and intubation were associated with transient autonomic responses in most patients. All autonomic signs indicated statistically significant sympathetic activation during saline-infiltrated tonsillectomies when compared with lidocaine-infiltrated sides (P<0001). Hypnotic measures (SE and RE) and finger temperatures did not differ between the sides. CONCLUSIONS: HR, PPI, PPGA, ANSS, ANSSI, SPI, and RE-SE detect autonomic responses to nociceptive stimuli and differentiate between tonsillectomies on locally anaesthetized tonsils from controls.


Subject(s)
Anesthetics, General/pharmacology , Anesthetics, Local/pharmacology , Autonomic Nervous System/drug effects , Lidocaine/pharmacology , Tonsillectomy , Adult , Anesthesia, General/methods , Anesthetics, Combined/pharmacology , Autonomic Nervous System/physiology , Blood Pressure/drug effects , Body Temperature/drug effects , Double-Blind Method , Entropy , Heart Rate/drug effects , Humans , Infusions, Intravenous , Intubation, Intratracheal/methods , Laryngoscopy , Monitoring, Intraoperative/methods , Young Adult
5.
Br J Anaesth ; 101(3): 383-9, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18628266

ABSTRACT

BACKGROUND: The surgical stress index (SSI), derived from a combination of heart rate (HR) and photoplethysmographic amplitude (PPGA) time series, is a novel method for continuous monitoring of intraoperative stress and has been validated in adults. The applicability of SSI and its constituents to monitoring children has not been previously evaluated. METHODS: In this controlled trial, 22 anaesthetized patients, aged 4-17 yr, undergoing strabismus surgery were randomized into two groups, Group LL and Group BSS. Patients in Group LL received topical conjunctival anaesthesia with a 1:1 mixture of lidocaine 2% and levobupivacaine 0.75%, and patients in Group BSS received balanced salt solution. RESULTS: Endotracheal intubation (n=22) increased median (range) SSI from 39.2 (22.6-55.6) to 53.6 (35.8-63.3) (P<0.001), decreased PPGA from 5.62 (2.79-9.69) to 5.27 (2.59-7.54)% (P=0.001), and increased the difference of response entropy (RE) and state entropy (SE) of frontal biopotentials (RE-SE) from 3.1 (0.06-9.1) to 5.7 (0.6-9.4) (P=0.01). Conventional haemodynamic variables also increased, median (range) HR from 72.9 (56.7-113.8) to 84.2 (60.4-124.8) beats min(-1) (P<0.001), and systolic non-invasive arterial pressure (S-NIBP) from 87 (78-143) to 103 (79-125) (P=0.007). When 3 min baseline before surgery was compared with 12 min of surgery, median (range) SSI increased from 43.3 (31.2-58.0) to 49.9 (39.3-57.2) (P=0.042) vs from 46.6 (26.8-57.8) to 52.1 (31.7-60.1) (P=0.024) and PPGA decreased from 6.60 (3.10-8.24) to 5.80 (3.03-7.65)% (P<0.001) vs from 5.51 (3.25-9.84) to 5.06 (3.08-8.99)% (P=0.042), in Groups LL and BSS, respectively, but SSI or other indicators did not differ significantly between the groups. CONCLUSIONS: SSI, PPGA, HR, NIBP, RE, and RE-SE detect autonomic responses to nociceptive stimuli in anaesthetized children undergoing strabismus surgery.


Subject(s)
Intraoperative Complications/diagnosis , Monitoring, Intraoperative/methods , Stress, Physiological/diagnosis , Adolescent , Anesthesia, General/methods , Anesthesia, Local/methods , Child , Child, Preschool , Double-Blind Method , Female , Heart Rate , Humans , Intubation, Intratracheal , Male , Photoplethysmography
6.
Br J Anaesth ; 98(4): 447-55, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17329347

ABSTRACT

BACKGROUND: Inadequate analgesia during general anaesthesia may present as undesirable haemodynamic responses. No objective measures of the adequacy of analgesia exist. We aimed at developing a simple numerical measure of the level of surgical stress in an anaesthetized patient. METHODS: Sixty and 12 female patients were included in the development and validation data sets, respectively. All patients had elective surgery with propofol-remifentanil target controlled anaesthesia. Finger photoplethysmography and electrocardiography waveforms were recorded throughout anaesthesia and various waveform parameters were extracted off-line. Total surgical stress (TSS) for a patient was estimated based on stimulus intensity and remifentanil concentration. The surgical stress index (SSI) was developed to correlate with the TSS estimate in the development data set. The performance of SSI was validated within the validation data set during and before surgery, especially at skin incision and during changes of the predicted remifentanil effect-site concentration. RESULTS: SSI was computed as a combination of normalized heart beat interval (HBI(norm)) and plethysmographic pulse wave amplitude (PPGA(norm)): SSI = 100-(0.7*PPGA(norm)+0.3*HBI(norm)). SSI increased at skin incision and stayed higher during surgery than before surgery; SSI responded to remifentanil concentration changes and was higher at the lower concentrations of remifentanil. CONCLUSIONS: SSI reacts to surgical nociceptive stimuli and analgesic drug concentration changes during propofol-remifentanil anaesthesia. Further validation studies of SSI are needed to elucidate its usefulness during other anaesthetic and surgical conditions.


Subject(s)
Anesthesia, General/methods , Intraoperative Complications/diagnosis , Monitoring, Intraoperative/methods , Severity of Illness Index , Stress, Physiological/diagnosis , Adult , Aged , Analgesics, Opioid/administration & dosage , Anesthetics, Combined/administration & dosage , Anesthetics, Intravenous/administration & dosage , Dose-Response Relationship, Drug , Electrocardiography/drug effects , Female , Heart Rate/drug effects , Humans , Middle Aged , Models, Neurological , Photoplethysmography , Piperidines/administration & dosage , Propofol/administration & dosage , Remifentanil , Signal Processing, Computer-Assisted , Stress, Physiological/etiology
7.
Acta Anaesthesiol Scand ; 49(4): 558-62, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15777306

ABSTRACT

BACKGROUND: Bromage scale (0-3) is used to measure the degree of motor block during spinal anaesthesia. However, an estimation of motor block is difficult during surgery. The purpose of this study was to evaluate the feasibility of surface EMG describing spontaneous muscular activity in the lower extremities during spinal anaesthesia. METHODS: In part I of the study, 13 patients undergoing day case surgery were studied. They received 10 mg hyperbaric bupivacaine at interspace L3-4. EMG, sensory and muscular block were measured at 5-min intervals during the first 30 min and then every 15 min until the patient was able to flex the knee. In part II of the study, 16 patients undergoing knee arthroplasty received 10 mg bupivacaine through spinal catheter at interspace L3-4 (Group CSA). An additional bolus of 2.5 mg was administered using EMG-guidance, if needed. Another group, 15 patients, received a single bolus of bupivacaine (15-20 mg) at L3-4 (Group Bolus). EMG, muscular and sensory block were monitored as described above. The epidural catheter was used as rescue. RESULTS: Part I: EMG compared to modified Bromage scale showed a significant correlation (P < 0.01, Spearman rank correlation). Part II: The amount of bupivacaine was significantly reduced with EMG guidance when compared with the single bolus group (14.0 mg vs. 17.0 mg) (P < 0.05 Mann-Whitney U). Motor block started to recover before the sensory block in 7/15 CSA patients vs. 1/15 Bolus patient. CONCLUSION: Stable maximal sensory block does not necessarily correlate with adequate motor block in patients receiving spinal anaesthesia induced with small bolus doses. In spite of electrical noise, EMG-guided administration of spinal anaesthesia significantly reduced the amount of bupivacaine compared to the hospital routine. Further studies are needed to develop the method.


Subject(s)
Anesthesia, Spinal , Arthroplasty, Replacement, Knee , Electromyography/methods , Monitoring, Intraoperative/methods , Muscle, Skeletal/physiology , Adult , Aged , Ambulatory Surgical Procedures , Double-Blind Method , Feasibility Studies , Female , Humans , Male , Middle Aged
8.
Appl Microbiol Biotechnol ; 67(4): 495-505, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15650852

ABSTRACT

Two endoxylanases, Nf Xyn11A and Nf Xyn10A, were cloned from a Nonomuraea flexuosa (previously Actinomadura flexuosa) DSM43186 genomic expression library in Escherichia coli. The coding sequences of xyn11A and xyn10A consist of 344 and 492 amino acids, respectively. The catalytic domains belong to family 11 and family 10 of glycoside hydrolases. The C-termini share strong amino acid sequence similarity to carbohydrate-binding module (CBM) families CBM2 and CBM13, respectively. Native Nf Xyn11A, and recombinant Xyn11A expressed in the filamentous fungus Trichoderma reesei, were purified from cultivation media and characterized. The molecular masses of the full-length enzymes determined by mass spectrometry were 32.9 kDa and 33.4 kDa, the recombinant enzyme having higher molecular mass due to glycosylation. In addition, shorter polypeptides with molecular masses of 23.8 kDa and 22.0 kDa were characterized from the T. reesei culture medium, both lacking the C-terminal CBM and the 22.0 kDa polypeptide also lacking most of the linker region. The recombinant polypeptides were similar to each other in terms of specific activity, pH and temperature dependence. However, the 23.8 kDa and 22.0 kDa polypeptides were more thermostable at 80 degrees C than the full-length enzyme. All polypeptide forms were effective in pretreatment of softwood kraft pulp at 80 degrees C.


Subject(s)
Actinomycetales/enzymology , Endo-1,4-beta Xylanases/genetics , Endo-1,4-beta Xylanases/metabolism , Peptides/metabolism , Recombinant Fusion Proteins/metabolism , Trichoderma/enzymology , Actinomycetales/genetics , Amino Acid Sequence , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Base Sequence , Biotechnology/methods , Enzyme Stability , Hot Temperature , Molecular Sequence Data , Peptides/isolation & purification , Recombinant Fusion Proteins/isolation & purification , Sequence Analysis, DNA , Trichoderma/genetics
10.
Acta Anaesthesiol Scand ; 47(3): 347-54, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12648203

ABSTRACT

BACKGROUND: When administered intrathecally, alpha-2 adrenergic agonists produce spinally mediated antinociception, but also rapidly redistribute to supraspinal sites. This investigation the compared EMG effects of intrathecally administered dexmedetomidine, MPV-2426 (fadolmidine), and tizanidine in Sprague-Dawley rats, which has not been previously described. METHODS: We studied electromyographic (EMG) responses of the head and gastrocnemius muscles, antinociception using the tail-flick test, and sedation by using observer assessment. Saline, dexmedetomidine (0.5 microg, 2.5 microg and 12.5 microg), MPV-2426 (2 microg, 10 microg and 50 microg) and tizanidine (2 microg, 10 microg and 50 microg) were administered intrathecally. RESULTS: Tizanidine 50 microg, MPV-2426 10 microg and 50 microg, and dexmedetomidine 2.5 microg and 12.5 microg, decreased EMG activity (P < 0.005). Dexmedetomidine 12.5 microg, MPV-2426 50 microg, and tizanidine 10 microg and 50 microg increased tail-flick latencies (P < 0.01). Dexmedetomidine alone significantly increased the magnitude of observer-assessed sedation (P < 0.0001). CONCLUSION: We conclude that in rats, intrathecally administered dexmedetomidine, MPV-2426 and tizanidine have dose-dependent effects on EMG. At antinociceptive doses, the EMG effects of these three alpha-2 adrenergic agonists differ (dexmedetomidine > MPV-2426 > tizanidine).


Subject(s)
Adrenergic alpha-Agonists/pharmacology , Clonidine/analogs & derivatives , Clonidine/pharmacology , Dexmedetomidine/pharmacology , Imidazoles/pharmacology , Indans/pharmacology , Muscle, Skeletal/drug effects , Adrenergic alpha-Agonists/administration & dosage , Animals , Behavior, Animal/drug effects , Clonidine/administration & dosage , Dexmedetomidine/administration & dosage , Dose-Response Relationship, Drug , Electromyography/drug effects , Hypnotics and Sedatives , Imidazoles/administration & dosage , Indans/administration & dosage , Injections, Spinal , Motor Activity/drug effects , Pain Measurement/drug effects , Pain Threshold/drug effects , Rats , Rats, Sprague-Dawley
12.
Eur J Anaesthesiol ; 20(2): 87-92, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12622489

ABSTRACT

BACKGROUND AND OBJECTIVE: The aim was to train artificial neural nets to predict the recovery of a neuromuscular block during general anaesthesia. It was assumed that the initial/early neuromuscular recovery data with the simultaneously measured physical variables as inputs into a well-trained back-propagation neural net would enable the net to predict a rough estimate of the remaining recovery time. METHODS: Spontaneous recovery from neuromuscular block (electrically evoked electromyographic train-of-four responses) were recorded with the following variables known to affect the block: multiple minimum alveolar concentration, end-tidal CO2 concentration, and peripheral and central temperature. RESULTS: The mean prediction errors, mean absolute prediction errors, root-mean-squared prediction errors and correlation coefficients of all the nets were significantly better than those of average-based predictions used in the study. The root-mean-squared prediction error of the net - employing minimum alveolar concentrations from the whole recovery period (the recovery time from E2/E1 = 0.30 to E4/E1 = 0.75; E1 = first response of train-of-four, E2 = second response of train-of-four, etc.)--were significantly smaller than those of other nets, or the same net employing minimum alveolar concentrations only from the initial recovery period (from E2/E1 = 0.30 to E4/E1 = 0.25). CONCLUSIONS: Neural nets could predict individual recovery times from the neuromuscular block significantly better than the average-based method used here, which was supposed to be more accurate than guesses by any clinician. The minimum alveolar concentration was the only monitored variable that influenced the recovery rate, but it did not aid neural net prediction.


Subject(s)
Anesthesia Recovery Period , Neural Networks, Computer , Neuromuscular Blockade/statistics & numerical data , Anesthesia, General/statistics & numerical data , Anesthetics, Inhalation/therapeutic use , Electromyography/statistics & numerical data , Humans , Isoflurane/therapeutic use , Neuromuscular Nondepolarizing Agents/therapeutic use , Predictive Value of Tests , Time Factors , Vecuronium Bromide/therapeutic use
13.
Arch Otolaryngol Head Neck Surg ; 127(9): 1106-12, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11556862

ABSTRACT

OBJECTIVES: To assess the morbidity and efficacy of bipolar radiofrequency thermal ablation tonsillectomy and compare it with traditional cold dissection tonsillectomy with diathermy hemostasis. DESIGN: Prospective, randomized, single-blinded, controlled clinical study. SETTING: Helsinki University Central Hospital, Department of Otorhinolaryngology-Head & Neck Surgery, Helsinki, Finland. PATIENTS: Forty healthy volunteer patients aged 18 to 65 years admitted for elective tonsillectomy with recurrent or chronic tonsillitis, obstructive tonsillar hypertrophy, or history of quinsy. Two patients were excluded from the study and 1 patient cancelled the operation. INTERVENTIONS: Nineteen patients underwent a traditional cold dissection tonsillectomy with diathermy hemostasis, and 18 patients underwent a bipolar radiofrequency thermal ablation tonsillectomy. There was no intergroup difference in age, sex, weight, and indications for tonsillectomy. The subjects were not informed of the type of procedure until the telephone interview 3 weeks after the operation. MAIN OUTCOME MEASURES: Operating time and intraoperative blood loss; need for anesthetics during the operation; different recovery indicators in the recovery room (ie, duration and medications administered), surgical ward (ie, medications administered, use of corticosteroids, general condition, and status of the uvula on the first postoperative day), and in the 2 weeks following surgery (ie, visual analog scale scores on 6 symptoms, medications needed, the day patients returned to work, use of antibiotics, and retreatment acceptance); and complications and certain laboratory parameters. RESULTS: There was a statistically significant but clinically insignificant difference in operating time and intraoperative blood loss in favor of the traditional tonsillectomy group. The other outcome measures showed no statistically significant differences. CONCLUSION: Bipolar radiofrequency thermal ablation and traditional tonsillectomy were associated with similar postoperative morbidity.


Subject(s)
Electrocoagulation , Tonsillectomy/methods , Tonsillitis/surgery , Adolescent , Adult , Aged , Humans , Middle Aged , Pharyngeal Diseases/surgery , Pilot Projects , Prospective Studies , Single-Blind Method
14.
Anaesth Intensive Care ; 29(4): 371-6, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11512647

ABSTRACT

In 1968, Waud presented his general pharmacodynamic model consisting of two sub-functions that divide the pharmacodynamic cascade from drug concentration to cell effect/response into two successive steps: Step one (the internal function) characterizes the binding of agonist drug molecules to the post-synaptic receptors and the subsequent receptor activation, and step two (the external/effect function) characterizes the cell response induced by a critical receptor pool activation. According to Waud, the problem of determining the relation between drug concentration and cell response/effect reduces to the second step in the pharmacodynamic cascade. In this paper, we suggest a new external/effect-function, the cumulative Normal population-effect-function. It describes how muscle fibre excitability (all-or-none phenomenon) is distributed as a function of mean fractional receptor activation in a muscle fibre population. This function fits to empirical data and explains logically why the sigmoid muscle effect, from minimal to maximal, is seen in such a narrow range of antagonist concentrations and receptor occupancies.


Subject(s)
Muscle Fibers, Skeletal/physiology , Neuromuscular Nondepolarizing Agents/pharmacology , Receptors, Neurotransmitter/drug effects , Receptors, Neurotransmitter/physiology , Action Potentials , Electric Stimulation , Electromyography , Evoked Potentials , Humans , Isoquinolines/pharmacology , Mivacurium , Models, Biological , Reference Values , Ulnar Nerve/physiology
15.
Br J Anaesth ; 85(5): 708-11, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11094585

ABSTRACT

Patients undergoing intraocular surgery are elderly and may have disease or be receiving medication which increases the risk of haemorrhage. We interviewed 1383 consecutive patients scheduled for eye surgery requiring retrobulbar/peribulbar block about their use of non-steroidal anti-inflammatory drugs, oral steroids and warfarin. A history of diabetes mellitus and globe axial length was noted. Medial peribulbar and inferolateral retrobulbar blocks were performed by three specialists and six doctors in training. The ensuing haemorrhages were graded as follows: 1 = spot ecchymosis; 2 = lid ecchymosis involving half of the lid surface area or less; 3 = lid ecchymosis all around the eye, no increase in intraocular pressure; 4 = retrobulbar haemorrhage with increased intraocular pressure. Acetylsalicylic acid was taken by 482 (35%) patients, non-steroidal anti-inflammatory drugs by 260 (19%) and warfarin by 76 (5.5%). Lid haemorrhages (grades 1-3) were observed in 55 patients (4.0%); in 33 of these patients the haemorrhages were spotlike (grade 1). No grade 4 haemorrhages occurred. The preoperative use of acetylsalicylic acid, non-steroidal anti-inflammatory drugs or warfarin, whether or not they had been discontinued, did not predispose to haemorrhage associated with retrobulbar/peribulbar block.


Subject(s)
Anesthesia, Local/adverse effects , Eye Hemorrhage/etiology , Ophthalmologic Surgical Procedures , Retrobulbar Hemorrhage/etiology , Adult , Aged , Aged, 80 and over , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Anticoagulants/adverse effects , Aspirin/adverse effects , Eyelid Diseases/etiology , Female , Humans , Male , Middle Aged , Prospective Studies , Risk Factors , Warfarin/adverse effects
16.
Anesth Analg ; 91(4): 934-7, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11004052

ABSTRACT

UNLABELLED: Hyaluronidase 7.5 IU/mL added to the local anesthetic improves peribulbar block, but smaller concentrations have not been shown to be effective. In this prospective, double-blinded study, 714 consecutive ocular surgery patients were randomized into three groups: no hyaluronidase (n = 241), hyaluronidase 3.75 IU/mL (n = 244), and hyaluronidase 7.5 IU/mL (n = 229). Retrobulbar/peribulbar block was performed with two injections of a 1:1 mixture of bupivacaine 0.75% and lidocaine 2%, 6-8 mL. Patient data were collected on demographics, initial volume of local anesthetic, need for supplementary block, and akinesia of the anesthetized eye. When hyaluronidase was used (3.75 or 7.5 IU/mL), the initial block was sufficient and the anesthetized eye was akinetic significantly more often than in the group without hyaluronidase. The hyaluronidase groups (3.75 and 7.5 IU/mL) did not differ significantly in any respect. We conclude that the addition of hyaluronidase 3.75 or 7.5 IU/mL improved the success of the initial retrobulbar/peribulbar block and akinesia and reduced the need for supplementary block. IMPLICATIONS: We conclude that the addition of hyaluronidase 3.75 or 7.5 IU/mL improved the success of the initial retrobulbar/peribulbar block and akinesia and reduced the need for supplementary block.


Subject(s)
Adjuvants, Anesthesia/administration & dosage , Anesthetics, Local/administration & dosage , Bupivacaine/administration & dosage , Hyaluronoglucosaminidase/administration & dosage , Lidocaine/administration & dosage , Nerve Block , Optic Nerve , Adolescent , Adult , Aged , Aged, 80 and over , Double-Blind Method , Eye Movements/drug effects , Female , Glaucoma/surgery , Humans , Injections , Male , Middle Aged , Oculomotor Muscles/drug effects , Phacoemulsification , Prospective Studies , Treatment Outcome
19.
Reg Anesth Pain Med ; 24(4): 341-6, 1999.
Article in English | MEDLINE | ID: mdl-10445774

ABSTRACT

BACKGROUND AND OBJECTIVES: Brief analgesia is needed to complete krypton laser cyclophotocoagulation for glaucoma patients and is advantageous in argon laser panphotocoagulation for diabetic retinopathy. We studied whether 0.2% ropivacaine, known for analgesia with minimal motor block or 1% lidocaine, with rapid onset and short duration of action, both supplemented with hyaluronidase, are suitable local anesthetics for retrobulbar/peribulbar block for these procedures. METHODS: Seventy-four treatment sessions of 65 patients were included in this prospective, randomized, double-blind study. Data were collected on adequacy of analgesia, need for supplementary blocks and eye movements at 10 minutes after injecting the block and at the end of the treatment, and need for patching the eye at discharge. RESULTS: Frequency of inadequate analgesia (24% in ropivacaine group and 32% in lidocaine group), and of supplementary blocks (11% and 14%, respectively) did not differ between the groups and exceeded our clinically acceptable level. Ropivacaine produced less motor block than lidocaine at 10 minutes (P < .001) and at the end of the treatment (P = .002). However, at discharge, the eye was significantly more often patched in the ropivacaine (70%) group than in the lidocaine group (41 %) (P = .035). In the ropivacaine group, a mobile eye did not predict inadequate intraoperative analgesia, whereas in the lidocaine group it did (P = .001). CONCLUSION: According to our preliminary data, neither 0.2% ropivacaine nor 1% lidocaine reached acceptable frequencies of adequate analgesia during transscleral cyclophotocoagulation, while all retinal panphotocoagulations could be completed under the initial block.


Subject(s)
Amides , Anesthetics, Local , Laser Coagulation/methods , Lidocaine , Nerve Block/methods , Adult , Aged , Aged, 80 and over , Diabetic Retinopathy/surgery , Double-Blind Method , Female , Fentanyl/therapeutic use , Glaucoma/surgery , Humans , Male , Middle Aged , Pain/drug therapy , Prospective Studies , Ropivacaine
20.
Acta Crystallogr D Biol Crystallogr ; 55(Pt 5): 1058-60, 1999 May.
Article in English | MEDLINE | ID: mdl-10216305

ABSTRACT

Crystals of the catalytic core domain of a Trichoderma reesei beta-mannanase belonging to glycoside hydrolase family 5 have been grown by the sitting-drop method at room temperature using ammonium sulfate as precipitant. The crystals grow as thin colourless plates and belong to space group P21, with unit-cell parameters a = 50.0, b = 54.3, c = 60.2 A, beta = 111.3 degrees, and have a single monomer of mannanase in the asymmetric unit. Native data to 2.0 A resolution have been collected at room temperature using synchrotron radiation. Data for a platinum derivative have been collected to 1.65 A at 110 K in a very short time at the CCLRC Daresbury synchrotron source, using a charge-coupled device (CCD) as detector.


Subject(s)
Fungal Proteins/chemistry , Mannosidases/chemistry , Trichoderma/enzymology , Catalysis , Crystallization , Crystallography, X-Ray , Fungal Proteins/classification , Fungal Proteins/isolation & purification , Mannosidases/classification , Mannosidases/isolation & purification , beta-Mannosidase
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