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PubMed1994

The effect of comprehensive outpatient pulmonary rehabilitation on dyspnea.

To evaluate the effect of outpatient pulmonary rehabilitation (OPR) on dyspnea, we measured this symptom using a visual analogue scale during graded treadmill exercise testing and with baseline and transitional dyspnea indices (TDI). The latter measure overall dyspnea in three spheres: functional impairment, magnitude of task, and magnitude of effort. Twenty patients with COPD referred for OPR were randomly assigned to either a treatment group (T, n = 10), with dyspnea evaluated at baseline then shortly following a 6-week OPR program, or a control group (C, n = 10), with dyspnea evaluated at baseline then following a 6-week waiting period. No significant change in maximal exercise performance from baseline to repeated testing was observed in either group. Dyspnea at maximum treadmill workload (Dmax), which did not significantly change in C, decreased from 74.4 +/- 18.9 percent at baseline to 50.5 +/- 23.2 percent post-OPR in T (p = 0.006). The Dmax related to minute ventilation (Dmax/VEmax) and oxygen consumption (Dmax/VO2max) also significantly decreased following OPR. The reduction in exertional dyspnea was apparent by the second minute of exercise. Additionally, TDI focal scores were significantly higher in T than C (2.3 +/- 1.06 vs 0.2 +/- 1.75 units, p = 0.006), indicating decreased overall dyspnea following OPR. These results point to significant improvements in both exertional and clinically assessed dyspnea following OPR.

Aged↗

PubMed2002

Attenuation of pressure swings along the endotracheal tube is indicative of optimal distending pressure during high-frequency oscillatory ventilation in a model of acute lung injury.

We tested the hypothesis that during high-frequency oscillatory ventilation, the oscillatory pressure ratio (OPR) is minimal at the optimal mean airway pressure (Paw). OPR is defined as the ratio of pressure swings at the distal end and the proximal opening of the endotracheal tube. Optimal Paw was assumed to be the lowest Paw at which the physiological shunt fraction was below 0.1. Acute lung injury was produced by saline lung lavage of pigs who were then subjected to a stepwise increase of Paw to impose underinflation, optimal inflation, and overdistention (inflation phase), followed by a stepwise decrease of Paw (deflation phase). OPR reached a minimum of 0.10 +/- 0.01 at Paw = 31 +/- 4 cm H(2)O during the inflation phase and a minimum of 0.04 +/- 0.01 at Paw = 18 +/- 1 cm H(2)O during the deflation phase. Optimal Paw was 31 +/- 4 cm H(2)O on the inflation limb and 14 +/- 2 cm H(2)O on the deflation limb. Paw at the minimal OPR was not significantly different from the optimal Paw during the inflation phase, and slightly but significantly higher (4.1 +/- 1.6 cm H(2)O) during the deflation phase. In conclusion, a consistent relationship was found between OPR and Paw, with a minimum in all animals. The minimal OPR coincides fairly well with the Paw where oxygenation is optimal.

Animals↗

PubMed2005

Genomic analysis of the 12-oxo-phytodienoic acid reductase gene family of Zea mays.

The 12-oxo-phytodienoic acid reductases (OPRs) are enzymes that catalyze the reduction of double bonds adjacent to an oxo group in alpha,beta-unsaturated aldehydes or ketones. Some of them have very high substrate specificity and are part of the octadecanoid pathway which convert linolenic acid to the phytohormone jasmonic acid (JA). Sequencing and analysis of ESTs and genomic sequences from available private and public databases revealed that the maize genome encodes eight OPR genes. Southern blot analysis and mapping of individual OPR genes to maize chromosomes using oat maize chromosome addition lines provides independent confirmation of this number of OPR genes in maize. A survey of massively parallel signature sequencing (MPSS) assays revealed that transcripts of each OPR gene accumulate differentially in diverse organs of maize plants suggesting distinct biological functions. Similarly, RNA blot analysis revealed that distinct OPR genes are differentially regulated in response to stress hormones, wounding or pathogen infection. ZmOPR1 and/or ZmOPR2 appear to function in defense responses to pathogens because they are transiently induced by salicylic acid (SA), chitooligosaccharides, and by infection with Cochliobolus carbonum, Cochliobolus heterostrophus and Fusarium verticillioides, but not by wounding. In contrast to these two genes, transcript levels of ZmOPR6 and ZmOPR7 and/or ZmOPR8 are highly induced by wounding or treatments with the wound-associated signaling molecules JA, ethylene and abscisic acid. However, accumulation of ZmOPR6 and ZmOPR7/8 mRNAs was not upregulated by SA treatments or by pathogen infection suggesting specific involvement in the wound-induced defense responses. None of the treatments induced transcripts of ZmOPR3, 4, or 5.

Abscisic Acid↗

PubMed1995

DAMGO, a mu-opioid receptor selective ligand, distinguishes between mu-and kappa-opioid receptors at a different region from that for the distinction between mu- and delta-opioid receptors.

The structural basis of opioid receptors (OPRs) for the subtype-selective binding of DAMGO, a mu-opioid receptor selective ligand, was investigated using chimeric mu/kappa-OPRs. Replacement of the region from the middle of the fifth transmembrane domain to the C-terminal of mu-OPR with the corresponding region of mu-OPR remarkably decreased the binding affinity to DAMGO, while the reciprocal chimera revealed the high affinity to DAMGO. These results indicate that DAMGO distinguishes between mu- and mu-OPRs at the region around the third extracellular loop, different from the case of the distinction between mu-and delta-OPRs in which the region around the first extracellular loop is important. Furthermore, displacement studies revealed that the region around the third extracellular loop is involved in the discrimination between mu- and kappa-OPRs not only by peptidic mu- selective ligands but also by non-peptidic ligands, such as morphine and naloxone.

Amino Acid Sequence↗

PubMed1995

Double in situ hybridization study on coexistence of mu-, delta- and kappa-opioid receptor mRNAs with preprotachykinin A mRNA in the rat dorsal root ganglia.

Coexistence of the mRNA for each subtype of opioid receptor (OPR) with the mRNA for preprotachykinin A (PPTA), a precursor protein of substance P (SP), in the rat dorsal root ganglia was examined by double in situ hybridization technique. About 90% and 30% of PPTA mRNA-positive neurons expressed mu- and kappa-OPR mRNAs at high level, respectively. However, only about 3% of PPTA mRNA-positive neurons expressed delta-OPR mRNA at high level. These results suggest that mu- and kappa-OPRs exist on most of and a part of the primary afferent terminals containing SP, respectively. On the other hand, among the neurons which highly expressed mu-, delta- or kappa-OPR mRNA, PPTA mRNA was not expressed in about 58%, 95% or 24% of those neurons, respectively. These findings suggest the possibility that OPRs co-exist with other neurotransmitters and/or neuromodulators than SP in the primary afferent neurons.

Animals↗

PubMed2005

Novel evolutionary lineages of the invertebrate oxytocin/vasopressin superfamily peptides and their receptors in the common octopus (Octopus vulgaris).

The common octopus, Octopus vulgaris, is the first invertebrate species that was shown to possess two oxytocin/vasopressin (OT/VP) superfamily peptides, octopressin (OP) and cephalotocin (CT). Previously, we cloned a GPCR (G-protein-coupled receptor) specific to CT [CTR1 (CT receptor 1)]. In the present study, we have identified an additional CTR, CTR2, and a novel OP receptor, OPR. Both CTR2 and OPR include domains and motifs typical of GPCRs, and the intron- exon structures are in accord with those of OT/VP receptor genes. CTR2 and OPR expressed in Xenopus oocytes induced calcium-mediated inward chloride current in a CT- and OP-specific manner respectively. Several regions and residues, which are requisite for binding of the vertebrate OT/VP receptor family with their ligands, are highly conserved in CTRs, but not in OPR. These different sequences between CTRs and OPR, as well as the amino acid residues of OP and CT at positions 2-5, were presumed to play crucial roles in the binding selectivity to their receptors, whereas the difference in the polarity of OT/VP family peptide residues at position 8 confers OT and VP with the binding specificity in vertebrates. CTR2 mRNA was present in various peripheral tissues, and OPR mRNA was detected in both the nervous system and peripheral tissues. Our findings suggest that the CT and OP genes, similar to the OT/VP family, evolved through duplication, but the ligand-receptor selectivity were established through different evolutionary lineages from those of their vertebrate counterparts.

Amino Acid Sequence↗

PubMed1987

Common mechanism controlling phase and antigenic variation in pathogenic neisseriae.

The expression of the Neisseria gonorrhoeae opacity protein (Op, protein II), a major antigenic determinant of the outer membrane, is subject to frequent phase transitions. At least nine expression loci (opaE) are involved in the production of a large number of serologically distinct Op types. Using opa-specific oligonucleotides as probes in genomic blots, we detect Op-related gene sequences (opr) in N. meningitidis as well as in N. lactamica. DNA sequence analysis of such opr genes derived from N. meningitidis reveals distinct regions of homology with gonococcal opa E genes. As shown in the immunoblot, the proteins encoded by opa and opr are serologically related. Like the opaE genes, the 5'-coding sequences of the opr genes include a repetitive sequence composed of pentameric CTCTT units. The number of these coding repeat (CR) units is variable. This finding, together with the observation that all opr genes are constitutively transcribed, regardless of the status of protein production, suggests a translational control mechanism identical to that of the opa genes in gonococci. The related structures and control mechanisms of opa and opr genes imply a general significance of their gene products for the pathogenic character of the investigated Neisseria species.

Amino Acid Sequence↗

PubMedDate not supplied

Arrays in rays: terminal addition in echinoderms and its correlation with gene expression.

The echinoderms are deuterostomes that superimpose radial symmetry upon bilateral larval morphology. Consequently, they are not the first animals that come to mind when the concepts of segmentation and terminal addition are being discussed. However, it has long been recognized that echinoderms have serial elements along their radii formed in accordance with the ocular plate rule (OPR). The OPR is a special case of terminal growth, forming elements of the ambulacra that define the rays in echinoderms. New elements are added at the terminus of the ray, which may or may not be marked by a calcified element called the terminal plate (the "ocular" of sea urchins). The OPR operates in every echinoderm, from the occasionally bizarre fossils of the Cambrian to the most familiar extant taxa. Using the OPR and other criteria of recognition, echinoderm body wall can be divided into two main regions: extraxial components are associated with the somatocoels, axial components (formed in accordance with the OPR) with the hydrocoel. We compare patterns of development in axial regions of echinoderms with those found in the anterior-posterior axes of the earliest echinoderms as well as other invertebrates. Although axial and extraxial skeletons appear to be composed of the same biomineral matrix, the genes involved in patterning these two skeletal components are likely distinct. During development of the axial skeleton, for instance, the genes engrailed and orthodenticle are expressed in spatial and temporal patterns consistent with the OPR. Other genes such as distal-less seem to demarcate early ontogenetic boundaries between the axial rudiment and the extraxial larval body. There is a complex and pervasive reorganization of gene expression domains to produce the highly divergent morphologies seen in the Echinodermata. We integrate morphological and genetic information, particularly with respect to the origins of radial symmetry in the rudiment, and the concomitant development of the rays.

Animals↗

PubMed2006

[Prediction value for operative mortality of four different coronary artery bypass graft risk stratification models in Chinese patients].

OBJECTIVE: To assess the prognostic accuracy for operative mortality of 4 different risk stratification models in Chinese patients underwent (coronary artery bypass graft) CABG. METHODS: Between 2002 and 2003, all patients undergoing CABG in our institution were prospectively scored for operative mortality using Parsonnet, EuroSCORE, Cleveland and OPR scoring systems and operative mortality was registered. Operative mortality is defined as postoperative death of any cause during hospitalization. Calibration was estimated using the Hosmer-Lemeshow goodness-of-fit test. Discrimination was evaluated using receiver operating characteristic (ROC) curves and area under a ROC curve (AUC). RESULTS: Follow-up was able to be completed in 2251 prospectively scored patients. Registered operative mortality was 1.87% (42/2251). The overall expected mortality calculated by Parsonnet, EuroSCORE, Cleveland and OPR scoring systems were 5.78%, 2.82%, 3.30% and 1.65%, respectively. The actual operative mortality was within the range of 95% confidence interval of OPR model and the other 3 predicted significantly higher operative mortality. Among the four risk scores, Calibration was good in OPR model (chi(2) = 4.842, P = 20.182) and poor in other 3 models (P < 0.001) while discrimination was acceptable in Parsonnet, Cleveland and OPR scoring systems (AUC: 0.711, 0.754, 0.757, respectively) and excellent in EuroSCORE scoring system (0.813). CONCLUSION: For Chinese patients undergoing CABG, OPR scoring system best predicted the operative mortality. All systems could be used to discriminate operative mortality for individual patient.

China↗

PubMed2004

Developmental evaluation of children born to mothers occupationally exposed to waste anesthetic gases.

BACKGROUND: The etiology of developmental delay in children is frequently unknown. Increasing evidence supports the possibility that environmental and occupational factors might be part of the basis for such delays. This study focuses on the development of children born to mothers who were exposed during their pregnancy to waste anesthetic gases. METHODS: The study population included 40 children aged 5-13 years born to female anesthesiologists and nurses working in operating rooms (OpRs) exposed to waste anesthetic gases, and 40 unexposed children born to female nurses and physicians who worked in hospitals during their pregnancy but did not work in OpRs. The unexposed group was matched for children's age and gender and maternal occupation (nurses vs. doctors). By means of standardized developmental tests, the present study population was evaluated for their medical and neurodevelopmental state. Questionnaires were given for the detection of attention and activity levels as perceived by the parents. Additional questionnaires dealt with information concerning developmental milestones, maternal and fetal morbidity, and gynecological history. RESULTS: No differences were noted between the groups as newborns or in developmental milestones at the age of 5-13 years; however, the mean score of gross motor ability was significantly lower in the exposed versus the unexposed group. Additionally, the mean score of the DSM-III-R Parent-Teacher Questionnaire (PTQ) (i.e., measure of inattention/hyperactivity) was higher in the exposed group. The level of exposure, as measured by the number of weekly hours in the OpRs, was significantly and negatively correlated with fine motor ability and the score of IQ performance. CONCLUSIONS: Our study supports the hypothesis that occupational exposure to anesthetic gases might be a risk factor for minor neurological deficits of children born to mothers who work in OpRs and therefore indicates the need for more studies in this area and perhaps more caution among OpR pregnant women and employers.

Adolescent↗

PubMed1975

The beta-adrenoceptors of the lung mediating inhibition of antigen-induced histamine release.

The beta-adrenoceptor stimulants, isoprenaline (IPR), orciprenaline (OPR), terbutaline (TRB), and ITP were studied for effects on antigen-induced release of histamine from guinea-pig lung tissue and for effects on guinea-pig isolated trachea and heart. The order of potency for the agents in the four funct-ons studied were: (a) inhibition of histamine release, IPR greater than OPR approximately equal to TRB greater than ITP equal 0; (b) heart stimulation, chronotropic effect, IPR greater than OPR greater than ITP approximately equal to TRB; (c) heart stimulation, inotropic effect, IPR greater than OPR greater than ITP greater than TRB; (d) trachea relaxation: IPR greater than TRB greater than OPR greater than ITP. These findings suggest that the beta-adrenoceptors mediating inhibition of antigen-induced release of histamine are more related to those mediating trachea relaxation (beta2) than those mediating cardiac stimulation (beta1).

Adrenergic beta-Agonists↗

PubMed2002

The effects of aggregation-inducing motifs on amyloid formation of model proteins related to neurodegenerative diseases.

To examine the effects of aggregation-inducing motifs related to neurodegenerative diseases on amyloid formation of host protein, we prepared several chimera myoglobins, in which various aggregation-inducing motifs were inserted. The focused aggregation-inducing motifs included five (R5) or two (R2) oligopeptide repeats in yeast Sup35p, five octapeptide repeats (OPR) in the human prion protein, a nonamyloid beta component (NAC) in alpha-synuclein, and tandem repeats of 50 glutamines (Q50). Circular dichroism and infrared spectroscopies suggested that the OPR, R5, and Q50 motifs formed an antiparallel beta sheet as well as a random coil, whereas the R2 and NAC motifs mainly formed random coils. The OPR, R5, and Q50 mutants, but not the R2 and NAC mutants, readily formed the SDS-resistant aggregates under physiological condition, and electron microscopy revealed that the aggregates contained amyloid fibrils. The destabilization and increase in gyration radius of the OPR, R5, and Q50 mutants correlated with the tendency to form amyloid fibrils. A control mutant bearing a nonamyloidgenic sequence was also moderately destabilized but did not form amyloid fibrils. Therefore, we concluded that the OPR, R5, and Q50 motifs, even in a quite stable protein such as myoglobin, led the host protein to formation of amyloid fibrils under physiological condition.

Amino Acid Motifs↗

PubMed2000

How to program rate responsive pacemakers.

Because oxygen uptake (VO2) increases linearly with heart rate during exercise, the oxygen pulse reserve (OPR) method (VO2 reserve divided by heart rate reserve) may provide a valid guide for rate responsive parameter tailoring. Using custom-made software (Pacing Rate Profile Software [PRPS]) it is possible to predict the exercise pacing rate profile with significant accuracy, according to the patient's functional class when ergospirometry apparatus is not available for a cardiopulmonary stress test (CPX). PRPS for Windows is based on the OPR method and some known workload/metabolic cost of exercise relationships during effort. The present study had two aims; first, to evaluate the reliability of PRPS in accurately predicting pacing rate profiles; and second, the suitability of activity and metabolic rate responsive sensors in supplying pacing rates sufficiently near to those predicted using CPX or PRPS. To test the reliability of PRPS we studied 244 patients, NYHA Class I-II, under two different stress test protocols. In one, the bicycle protocol (25 W, 2-minute steps), we tested 137 normal patients (94 men and 43 women, mean age 67 +/- 15 years). Sixty-eight of these were simultaneously CPX tested. PRPS predicted pacing rates were matched against the patients' sinus rhythms or their theoretical CPX measured VO2 heart rates (OPR method). Linear regression analysis was highly significant (r = 0.93 and r = 0.97, respectively). The other, the treadmill protocol, consisted of three different protocols. (1) Speed Incremental Treadmill Stress Test (SITST): 57 patients underwent CPX (33 men and 24 women, mean age 67 +/- 15 years, NYHA Class I-II). All had been pacemaker implanted for SSS and/or advanced atrioventricular block (AVB). PRPS pacing rates were matched against CPX VO2 OPR calculated heart rates (r = 0.93), (linear regression analysis). (2) CAEP: 30 patients underwent CPX (26 men and 4 women, mean age 61 +/- 11 years, NYHA Class I-II). Thirteen of them had been pacemaker implanted for SSS and/or advanced AVB. In all 30 patients the PRPS rates were matched against CPX VO2 calculated rates (r = 0.90). In the 17 normal nonimplanted patients, the PRPS rates were also matched against sinus rhythms, (r = 0.80). (3) Weber: 20 patients underwent CPX (16 men and 4 women, mean age 68 +/- 8 years, NYHA Class I-II). As above, in six normal nonimplanted patients, statistical analysis between PRPS rates and sinus rhythms was performed (r = 0.89). The comparison between PRPS theoretical pacing rates and VO2 predicted rates in all 20 patients was also statistically significant (r = 0.93). Finally, to test the reliability of PRPS also in NYHA Class III-IV patients, we tested 22 implanted patients (15 men and 7 women, mean age 70 +/- 9 years) and compared PRPS predicted rates against VO2 CPX measured rates (r = 0.92). To determine if the wide variety of RR pacers were able to supply pacing rates near to those predicted, whether by means of CPX or PRPS, we studied a total of 89 patients: 49 of these (26 men and 23 women, mean age 66 +/- 12 years) had been implanted with activity sensors; 12 patients (11 men and one woman, mean age 70 +/- 7 years) had been implanted with metabolic sensors, and finally 28 patients (19 men and 9 women, mean age 70 +/- 12 years) had been implanted with dual sensors (activity + QT or minute ventilation). Linear regression analysis showed r = 0.93 for activity sensors, r = 0.94 for metabolic sensors, and r = 0.92 for dual sensor. In conclusion, when rate responsive pacing causes symptoms or functional impairment, physicians must provide a personalized rate response tailoring derived from precise, simple physiological testing. OPR is an easy physiological method for tailoring rate response settings, suitable for activity and metabolic sensors. When ergospirometry apparatus is not available, PRPS can successfully replace CPX testing for tailoring.

Aged↗

PubMed1995

Identification of outer membrane proteins as target antigens of Pseudomonas aeruginosa Homma serotype M.

Pseudomonas aeruginosa is routinely serotyped in Japan by using the Homma scheme. The serotypes (O serotypes) are based on the chemical structure of the O-polysaccharide portion of the lipopolysaccharide (LPS). However, the nature of the Homma serotype M antigen has remained obscure because strains classified as serotype M usually have the rough phenotype. I characterized the target antigen of serotype M. The results of Western blotting (immunoblotting) showed that commercially available typing monoclonal antibody (MAb) against serotype M specifically bound to outer membrane protein (Opr) G and that typing rabbit antiserum specific for serotype M mainly contained antibodies against Oprs F and H2. These Oprs were distributed among all P. aeruginosa strains tested, including the serotype standard, serotype M and nontypeable strains, and a series of LPS-core-defective mutants derived from strain PAC1. However, the rough mutants derived from strain PAC1 agglutinated with the anti-serotype M antibodies, whereas the smooth strains did not. LPS preparations from serotype M strains possessed few or no polysaccharide chains. These strains had higher levels of binding activity with anti-serotype M MAb, as well as with anti-lipid A MAb, which specifically bound to the cell surface of the rough-natured gram-negative bacterial strains with high activity. The anti-serotype M antiserum also contained rough-LPS-specific antibodies, but the epitope was distributed among only a few strains. The results suggested that the Oprs acted as the serotype M antigen and that LPS did not. In conclusion, the rough strains agglutinated with anti-Opr antibodies and were distinguished as serotype M from the smooth strains of other serotypes, because the antibodies were accessible to the cell surface lacking O polysaccharides. I supposed that Homma serotype M is an index of the rough nature of P. aeruginosa strains rather than one of the O serotypes.

Animals↗

PubMed1997

'Cross talk' between opioid peptide and adrenergic receptor signaling in isolated rat heart.

BACKGROUND: Cardiac myocyte sarcolemma contains both catecholamine and opioid peptide receptors (OPRs). Opioid peptides are coreleased with catecholamines from nerve terminals in the heart. We investigated whether OPR stimulation influences the effects of beta-adrenergic receptor (beta-AR) stimulation in the isolated, isovolumic rat heart and whether the mechanism of such an interaction involves both beta-AR subtypes or an alteration in beta-AR-mediated increase in cAMP. METHODS AND RESULTS: Norepinephrine (NE, 10(-7) mol/L) increased peak left ventricular systolic pressure (LVSP) and cAMP more than twofold compared with controls. The delta-OPR agonist leucine-enkephalin (LE, 10(-8) mol/L) markedly inhibited the beta1-AR-induced positive inotropic effect and increase in cAMP but alone had no effect on basal LVSP or basal cAMP levels. The OPR antagonist naloxone 10(-8) mol/L added to LE+NE perfusate reversed the LE-induced decrease in cAMP and LVSP even though naloxone alone had no effect on LVSP and cAMP levels. LE could not counteract the twofold increase in LVSP produced by the nondegradable cAMP analog CPT-cAMP 2.3x10(-5) mol/L or a high concentration of forskolin (10(-7) mol/L) but did reverse the 173+/-11.8% and 135+/-13.6% increases in LVSP stimulated by 10(-8) and 0.5x10(-8) mol/L forskolin, respectively. LE inhibited cAMP production at all concentrations of forskolin (10(-7), 10(-8), and 0.5x10(-8) mol/L). Pertussis toxin (PTX) pretreatment abolished LE effects on beta1-AR stimulation. Zinterol 10(-5) and 10(-6) mol/L, a specific beta2-AR agonist that elicits a cAMP-independent inotropic effect in rat heart, caused 225+/-14% and 182+/-5% increases in LVSP that could not be reversed by addition of LE. CONCLUSIONS: Potent, inhibitory "cross talk" between delta-OPR and beta1-AR signaling pathways occurs via a PTX-sensitive G(i/o) protein involved in adenylyl cyclase inhibition in rat heart.

Adenylate Cyclase Toxin↗

PubMed2000

Intraocular pressure and pulse rate measurements by the OBF tonograph--comparison to reference instruments.

The purpose of this study was to evaluate the accuracy of intraocular pressure (IOP) and ocular pulse rate (OPR) measurements obtained by the Ocular Blood Flow (OBF) tonograph (OBF Labs, Wiltshire, UK). Measurements of IOP and OPR by the OBF tonograph were compared to those of reference instruments. For IOP evaluation, measurements were obtained on patients with normal and abnormal pressures using the OBF tonograph and the Goldmann applannation tonometer in random alternate order. For the OPR evaluation, measurements were obtained using the OBF tonograph with simultaneous heart rate monitoring by ECG on patients with normal IOP. The validity of the OBF tonograph measurements was quantified in terms of 95% limits of agreement and their relationships to measurements by reference instruments was determined by linear regression analyses. 102 patients were recruited for IOP measurements. Mean IOP obtained by the Goldmann tonometer was 20.7 mmHg (7-42 mmHg, SD 6.98) whilst mean IOP obtained by the OBF tonograph was 20.1 mmHg (8.1-40.2, SD 6.1). Goldmann IOP and OBF tonograph IOP readings were well correlated (r = 0.945). Analysis of the difference in IOP measurements between two instruments (tonograph minus Goldmann tonometer) showed the mean bias to be 0.26 mmHg (-7.8 to +6.1 mmHg) and the 95% limits of agreement to be -4.35 to +4.87 mmHg. Agreement between two instruments appeared to be dependent on the IOP; at IOP lower than 20.6 mmHg there was an overall tendency for the tonograph IOP to be higher than Goldmann IOP and vice versa when IOP was above 20.6 mmHg. 47 patients were recruited for OPR and ECG measurements. Mean pulse rates were 74.8 beats per min (mean 43-110) by ECG and 73.9 beats per min (43-110) by tonography. Analysis of the difference in pulse rate between instruments (tonograph OPR minus ECG pulse rate) against the average pulse rate showed the mean bias to be -0.8 beats and the 95% limits of agreement to be between -7 to +5 beats. Ocular pulse rate values obtained by the OBF tonograph were very accurate when compared to ECG pulse rate. This indicates that there is unlikely to be a systematic lag in continuous ocular pulse waveform recording. Intraocular pressure measurements by the OBF tonograph correlated very well with Goldmann readings over a wide range of pressures and should be valid in the clinical setting.

Heart Rate↗

PubMedDate not supplied

Support of cardiac performance following heart valve surgery by raising heart rate to the optimal pacing rate.

Effects of hemodynamic parameters of heart rate were studied in 19 patients with low cardiac output syndrome following open heart surgery for mitral and/or aortic valve replacement in the first five postoperative days. The central venous pressure (CVP), left atrial mean pressure (LAMP), and arterial blood pressures were determined at spontaneous heart rate (SHR), and during graded atrial (12 pts.) or ventricular (7 pts.) pacing each day. An "optimal pacing rate" (OPR), characterized by the most advantageous arterial pressures at the possible lowest levels of CVP and LAMP, and by the suppression of preexisting arrhythmias, if any, was established daily for maintaining each patient on that rate. The SHR was 69 +/- 9 and the OPR was 102 +/- 9 on the first postoperative day. For the fifth postoperative day the SHR was 68 +/- 10 and the OPR decreased to 90 +/- 9. Pacing with the OPR significantly increased cardiac performance. E.g. the hemodynamic improvement on the first postoperative day induced by pacing was comparable to the spontaneous improvement seen during the first five postoperative days. The hemodynamic effect of atrial pacing on circulation was more definitive than that of ventricular pacing. Since OPR may be significantly higher than SHR and varies from day to day, we suggest that, in cases where pacing is applied to improve cardiac performance, it be determined for each patient individually each postoperative day.

Adolescent↗

PubMed1989

Solubilization and purification of opioid receptor molecules of rat brain.

A P2 membrane preparation of rat brain (without cerebellum) was solubilized with CHAPS in Tris containing DTT and trypsin inhibitor. Two opiate ligands, 10b and 10cd, prepared by Liu et al, were employed consecutively in affinity chromatography, from which OPR's were eluted with Nx. The eluate was subsequently passed through a WGA affinity column and the OPR's eluted with N-GluNAc. This eluate was further purified and concentrated by preparative granular gel isoelectric focusing on SG200. Two protein peaks appeared separately at pH 5 and 7.8. The eluates from both peaks were examined for protein contents using the silver staining method, and binding activity was measured by RRA with 3H-etor. The results revealed that both samples contained active OPR purified to over 80,000 fold. The Mr was estimated by gel filtration to be 52 kD and 42 kD for OPR in the pH 5 and pH 7.8 samples respectively. OPR in the pH 5 sample have been determined to be of mu-type by their binding activity with 3H-ohm.

Animals↗