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1.
J Fish Biol ; 90(4): 1548-1569, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28097667

ABSTRACT

The comparative morphology of the scales of roundscale spearfish Tetrapturus georgii and white marlin Kajikia albida was investigated. In addition, variation in scale morphology across different body regions within each species was analysed. Although considerable morphological variation was observed among scales from different body regions in both species, scales of K. albida generally have pointed anterior ends, fewer posterior points and are more heavily imbricated than those of T. georgii, which are frequently rounded anteriorly, often have many posterior points and are separated farther within the skin. In all sampled body regions and individuals, scales of T. georgii are significantly broader and have a lower length-to-width aspect ratio than those of K. albida. Superficial to the scales are denticular plates, which are ossified formations occurring on the surface layer of the epidermis; these were observed and described for T. georgii, K. albida and blue marlin Makaira nigricans. Detailed scale descriptions allow for a more accurate characterization of the variation within and differences between these two species and could potentially be a valuable tool for investigating istiophorid systematics.


Subject(s)
Fishes/anatomy & histology , Fishes/physiology , Skin/anatomy & histology , Animals , Skin Physiological Phenomena
2.
J Fish Biol ; 89(3): 1666-91, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27460961

ABSTRACT

This study provides a complete description of the osteology of the crescent gunnel Pholis laeta based on cleared-and-stained specimens and X-rays to help provide sufficient morphological data to generate a robust phylogeny for the family Pholidae. Pholis laeta exhibits high variation in the structure of its caudal skeleton. The length of the preural (pu)2 neural spine is variably reduced (most common) or elongated (i.e. of similar length to that of pu3). Additionally, the neural spine of pu3 is either bifurcated or single. These results document and describe characters useful for phylogenetic inference of the family, including the insertion pattern of anal-fin pterygiophores between haemal spines. Pholidae was recovered as monophyletic (synapomorphies: ribs absent, haemonephropophyses present, gill membranes broadly joined, first neural arch fused to centrum, first anal-fin spine very robust, the dorsal fin comprises only spines and the presence of five branchiostegals), with monophyletic genera Pholis and Apodichthys (Rhodymenichthys is monotypic) and Apodichthys and Rhodymenichthys as sister taxa. The elongation of its pu2 neural spine defines Pholis and synapomorphies for Apodichthys include five infraorbital bones, no pelvic fin, a hypertrophied first anal-fin spine, the presence of two or three empty interhaemal spaces after the anteriormost anal-fin spine and having 35-46 abdominal vertebrae. Apodichthys and Rhodymenichthys are sister taxa based on the continuity of the caudal fin with the dorsal and anal fins and uniform colouration. Future study is needed to more fully resolve the interrelationships of species within Pholidae (especially the genus Pholis) and solidify the position of Pholidae within the Zoarcoidei.


Subject(s)
Bone and Bones/anatomy & histology , Perciformes/anatomy & histology , Perciformes/classification , Phylogeny , Animals , Osteology , Species Specificity , Spine/anatomy & histology
3.
J Fish Biol ; 89(2): 1494-500, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27354338

ABSTRACT

Three newly discovered larval specimens of the genus Muraenolepis collected from the waters of the western Antarctic Peninsula are described. Knowledge of their natural history is sparse and information about their early life history is based on only a few larval stages. Here, the available literature on larval eel cods is reviewed, and the specimens placed in context.


Subject(s)
Gadiformes/anatomy & histology , Animals , Antarctic Regions , Gadiformes/classification , Gadiformes/growth & development , Larva/anatomy & histology , Larva/classification
4.
J Clin Anesth Manag ; 1(1)2016 Jan.
Article in English | MEDLINE | ID: mdl-32500108

ABSTRACT

An observational clinical study to evaluate the effect of phenylephrine infusion on maternal temperatures during scheduled cesarean delivery under spinal anaesthesia was conducted in 40 ASA physical status II parturients. Following placement of spinal anesthesia, phenylephrine infusion was initiated at 40 µg/min and titrated to maintain mean arterial pressure within 20 percent of baseline. Maternal oral temperature, heart rate, and blood pressure were measured at baseline, spinal placement, every 10 minutes thereafter for 60 minutes. Phenylephrine dose received was documented every ten minutes. The range in maternal temperature change was 0.06-0.29°C. The lowest recorded temperature was 36.3°C. Decreased maternal temperature was associated with duration of anesthesia and cumulative phenylephrine dose in a univariate model (P<0.001 for all). The multivariable model showed an association between a greater decrease in maternal temperature with larger doses of phenylephrine being administered.

5.
Lett Appl Microbiol ; 61(2): 130-8, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25900660

ABSTRACT

UNLABELLED: Faecal indicator bacteria (FIB) and harmful algal blooms (HABs) threaten the health and the economy of coastal communities worldwide. Emerging automated sampling technologies combined with molecular analytical techniques could enable rapid detection of micro-organisms in-situ, thereby improving resource management and public health decision-making. We evaluated this concept using a robotic device, the Environmental Sample Processor (ESP). The ESP automates in-situ sample collection, nucleic acid extraction and molecular analyses. Here, the ESP measured and reported concentrations of FIB (Enterococcus spp.), a microbial source-tracking marker (human-specific Bacteriodales) and a HAB species (Psuedo-nitzschia spp.) over a 45-day deployment on the Santa Cruz Municipal Wharf (Santa Cruz, CA, USA). Both FIB and HABs were enumerated from single in-situ collected water samples. The in-situ qPCR efficiencies ranged from 86% to 105%, while the limit of quantifications during the deployment was 10 copies reaction(-1) . No differences were observed in the concentrations of enterococci, the human-specific marker in Bacteroidales spp., and P. australis between in-situ collected sample and traditional hand sampling methods (P > 0·05). Analytical results were Internet-accessible within hours of sample collection, demonstrating the feasibility of same-day public notification of current water quality conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: This study presents the first report of in-situ qPCR enumeration of both faecal indicators and harmful algal species in coastal marine waters. We utilize a robotic device for in-situ quantification of enterococci, the human-specific marker in Bacteriodales and Pseudo-nitzschia spp. from the same water samples collected and processed in-situ. The results demonstrate that rapid, in-situ monitoring can be utilized to identify and quantify multiple health-relevant micro-organisms important in water quality monitoring and that this monitoring can be used to inform same-day notifications.


Subject(s)
Enterococcus/isolation & purification , Environmental Monitoring/methods , Feces/microbiology , Harmful Algal Bloom , Real-Time Polymerase Chain Reaction/methods , Enterococcus/genetics , Humans , Robotics , Water Quality
6.
J Fish Biol ; 80(2): 335-45, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22268433

ABSTRACT

The present study of Lepisosteus osseus dimorphism expands upon previous work by examining a broader array of morphometric characters while removing the bias associated with overall body length. A stepwise discriminant function analyses (swDFA) found that five characters best distinguish the sexes: head width, mid-snout width, anal-fin height, anal-fin width and prepectoral-fin length. Discriminant function analyses (DFA) with the five characters yields misclassification rates of 23·5% for females and 9·7% for males. Subsequent DFA using these five characters plus standard length yields misclassification rates of only 8·8% for females and 6·2% for males. The data presented here reveal differences in head and anal-fin shape between male and female L. osseus that may have evolved to enhance predatory abilities or competitive abilities during reproduction. This study is the first to find that L. osseus exhibits sexual dimorphism in characters without the biases of overall size.


Subject(s)
Fishes/anatomy & histology , Sex Characteristics , Animals , Body Size , Discriminant Analysis , Female , Male
8.
Eye (Lond) ; 19(6): 670-5, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15359256

ABSTRACT

PURPOSE: To investigate intraocular pressure (IOP) and ocular haemodynamics following small incision cataract surgery. METHODS: Systemic and ocular haemodynamics, and IOP, were measured pre-operatively and 1 month post-operatively, in 25 eyes of 25 patients (mean age 72.6+/-7.9 years) scheduled for small incision cataract surgery and intraocular lens implantation; these values were compared to an untreated age-matched healthy group (n=25, mean age 72.3+/-5.0 years). For each eye, the Ocular Blood Flow Analyser (OBFA, Paradigm Inc., UT, USA) was used to obtain measurements of IOP, pulsatile ocular blood flow (POBF), pulse volume (PV), ocular pulse amplitude (PA), and pulse rate (PR). Systemic blood pressure measurements were obtained at each visit. Pre- and post-operative values for the cataract group were compared using repeated measures analysis of variance, and compared to the normal group using analysis of variance. RESULTS: Pre-operatively, IOP was significantly higher in the cataract group compared to the age-matched normal control group (P<0.001). Cataract surgery resulted in a significant 16.7% reduction in IOP (P=0.001). Consequently, the post-operative IOP in the cataract group was similar to that of the normal group (P>0.05). Both pre- and post-operative POBF and PV values for the cataract group were significantly lower than for the normal age-matched group (P<0.0125). Small incision cataract surgery led to an 8.3% post-operative increase in POBF (P=0.0118) and 15.5% increase in PV (P<0.001). No changes in PA or PR were evident. CONCLUSION: These data suggest that cataract patients exhibit higher IOP and reduced ocular perfusion characteristics compared to an age-matched normal healthy group. Following cataract surgery, IOP reduced and ocular pulsatility improved.


Subject(s)
Cataract Extraction/methods , Cataract/physiopathology , Lens Implantation, Intraocular/methods , Aged , Analysis of Variance , Case-Control Studies , Female , Humans , Intraocular Pressure , Male , Postoperative Period , Pulsatile Flow , Regional Blood Flow
9.
Emerg Med Australas ; 16(1): 13-6, 2004 Feb.
Article in English | MEDLINE | ID: mdl-15239749

ABSTRACT

Dizziness is a common symptom and a systematic method is required to make a diagnosis from its many possible causes. This article describes an approach to the problem with emphasis on true vertigo and in particular its otological aetiology. Important points in the history as well as relevant physical signs are described together with some readily identifiable conditions and their management.


Subject(s)
Emergency Treatment/methods , Vertigo , Central Nervous System Diseases/complications , Diagnosis, Differential , Ear Diseases/complications , Humans , Medical History Taking/methods , Nausea/etiology , Neck Injuries/complications , Neurologic Examination , Physical Examination , Vertigo/diagnosis , Vertigo/etiology , Vertigo/therapy , Vestibular Function Tests , Vomiting/etiology
10.
Br J Ophthalmol ; 88(3): 406-11, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14977778

ABSTRACT

AIM: To determine the ocular haemodynamic response to gas perturbations in glaucoma. METHODS: Intraocular pressure (IOP), systemic systolic and diastolic blood pressure (SBP and DBP), and retrobulbar blood flow velocities, measured by colour Doppler imaging (CDI), were recorded at two visits. CDI was used to measure peak systolic and end diastolic velocities (PSV and EDV) and resistance index (RI) in the ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliary arteries (SPCAs). At the first visit, measurements were taken at baseline (B1: breathing room air) and during isoxic hypercapnia (end tidal PCO(2) increased 15% above baseline) in 16 normal subjects and 12 patients with glaucoma. On another day, measurements were repeated at a second baseline (B2) and during hyperoxia (100% oxygen breathing) for 15 normal subjects and 13 glaucoma patients. Baseline systemic data were compared using paired t tests; REANOVA was performed to compare group differences at baseline and to determine the vessel response to each condition. Fisher's LSD was used for post hoc comparison. RESULTS: Baseline OA PSV was lower for the glaucoma than for the normal group (p = 0.047); the groups were otherwise similar at baseline. IOP demonstrated no response to hypercapnia, but reduced during hyperoxia for both the normal subjects (p<0.0001) and glaucoma patients (p = 0.04). During hypercapnia, SBP increased in normal subjects (p = 0.03) and glaucoma patients (p = 0.01); DBP increased in normal subjects (p = 0.021). There was a corresponding increase in ocular perfusion pressure (OPP) for normal subjects (p = 0.01) and glaucoma subjects (p = 0.028), and as a result OPP was included as a covariate in the REANCOVA model. Hypercapnia resulted in increased PSV in the CRA of normal subjects (p = 0.035) and increased PSV and EDV in the SPCAs of glaucoma patients (p = 0.041 and p = 0.030 respectively). Hyperoxia resulted in reduced PSV and EDV in the ophthalmic arteries of normal subjects only (p = 0.001 and 0.031 respectively). CONCLUSIONS: These findings suggest the presence of relative vasoconstriction in glaucoma patients, which is at least partially reversed by hypercapnia.


Subject(s)
Glaucoma/physiopathology , Hypercapnia/physiopathology , Hyperoxia/physiopathology , Vasomotor System/physiopathology , Adrenergic beta-Antagonists/therapeutic use , Analysis of Variance , Blood Flow Velocity , Blood Pressure , Glaucoma/drug therapy , Humans , Intraocular Pressure , Middle Aged , Perfusion , Pulse
11.
Br J Ophthalmol ; 87(1): 96-100, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12488271

ABSTRACT

BACKGROUND/AIM: Reduced cerebral blood flow and decreased glucose metabolism have been identified in epilepsy patients receiving vigabatrin. It is likely that such a change may extend to the eye and may be linked to previously reported irreversible visual field defects. The aim of this study was to determine whether patients who have undergone anti-epileptic drug (AED) therapy with vigabatrin have altered ocular haemodynamics. METHODS: The study cohort comprised 11 normal subjects (mean age 42.6 (SD 12.7) years and 17 epilepsy patients, of which 10 were either currently or previously treated with vigabatrin (38.6 (11.7) years) and seven were treated with AEDs excluding vigabatrin (46.0 (9.8) years). The three groups were matched at baseline for pulse rate, diastolic and systolic blood pressure, and intraocular pressure (IOP). At a single visit, the ocular blood flow analyser (OBFA; Paradigm Medical Instruments Inc, UT, USA) was used to measure pulsatile ocular blood flow (POBF) and pulse amplitude (PA) in each eye of all subjects. One way ANCOVA (with age as a covariate) was used to identify differences in POBF and PA between the groups. For the vigabatrin group only, Pearson's product moment correlation coefficient was used to explore potential interactions between ocular blood flow parameters and cumulative vigabatrin dose, duration, and maximum dose. RESULTS: Both the vigabatrin treated epilepsy group and conventionally treated epilepsy group exhibited significantly reduced POBF (p=<0.001, p=0.040) and PA (p=<0.001, p=0.005) compared to normal subjects. Patients treated with vigabatrin exhibited a further reduction in POBF (p=0.046) and PA (p=0.034) compared to conventionally treated epilepsy patients. No significant correlations were found between drug dosage and POBF and PA for the vigabatrin treated epilepsy group. CONCLUSIONS: A significant reduction in POBF and PA is apparent in epilepsy patients treated with AEDs when compared to normal subjects. A further reduction in POBF and PA is apparent between vigabatrin treated and conventionally treated patients. The reduction in ocular perfusion, which is more pronounced in patients previously treated with vigabatrin, may have implications in the impairment of visual function associated with the drug.


Subject(s)
Anticonvulsants/therapeutic use , Epilepsy/drug therapy , Eye/blood supply , Vigabatrin/therapeutic use , Adult , Analysis of Variance , Blood Pressure/drug effects , Blood Pressure/physiology , Cerebrovascular Circulation/physiology , Cohort Studies , Female , Humans , Intraocular Pressure/drug effects , Intraocular Pressure/physiology , Male , Middle Aged , Regional Blood Flow/drug effects
12.
J Med Screen ; 9(2): 74-82, 2002.
Article in English | MEDLINE | ID: mdl-12133927

ABSTRACT

BACKGROUND: Little is known about the factors influencing the risk of recall for assessment, invasive diagnostic procedures, and early rescreening after screening mammography. METHODS: From June 1996 to March 1998 women attending screening at 10 National Health Service Breast Screening Programme (NHSBSP) centres completed a self administered questionnaire and were followed up for their screening outcome. RESULTS: 1969 (3.3%) out of 60 443 women aged 50-64 who had never used hormone replacement therapy (HRT) were recalled for assessment but were not diagnosed with breast cancer (defined here as false positive recall). After adjustment for the variation between centres, false positive recall was decreased significantly among women who were likely to have had a previous NHSBSP mammogram (odds ratio (OR) 0.49, 95% confidence interval (95% CI) 0.38 to 0.63 for likely versus unlikely), who were postmenopausal (OR 0.65, 95% CI 0.56 to 0.76 for postmenopausal v premenopausal) and increased significantly for women reporting previous breast surgery (OR 1.64, 95% CI 1.42 to 1.89). Although false positive recall decreased significantly with parity and increasing body mass index, these effects were not large and no significant variation was found with age, education, family history of breast cancer, oral contraceptive use, sterilisation, exercise, smoking, or alcohol consumption. Altogether 655 (1.1%) women had an invasive diagnostic procedure; no personal characteristics were predictive of this outcome, 286(0.5%) were referred for early rescreening, and this was increased significantly by nulliparity and a family history of breast cancer. INTERPRETATION: Premenopausal women, those without a previous NHSBSP mammogram, and women with previous breast surgery have an increased risk of false positive recall by the NHSBSP.


Subject(s)
Breast Neoplasms/diagnostic imaging , Mammography , Mass Screening , Age Factors , Aged , Aged, 80 and over , Biopsy/statistics & numerical data , Breast Neoplasms/epidemiology , Breast Neoplasms/genetics , Breast Neoplasms/pathology , False Positive Reactions , Female , Humans , Mammography/methods , Mass Screening/statistics & numerical data , Menopause , Middle Aged , National Health Programs , Outcome Assessment, Health Care , Reproductive History , Risk Factors , Surveys and Questionnaires , United Kingdom/epidemiology
13.
Eye (Lond) ; 16(2): 156-62, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11988816

ABSTRACT

PURPOSE: To determine the effects of age on blood flow measurements obtained using the scanning laser Doppler flowmeter (SLDF). METHOD: Using SLDF (Heidelberg retina flowmeter, Heidelberg Engineering, Germany) three 10 degrees images were taken of the superior temporal retina and three further images of the superior temporal neuroretinal rim in 15 young, healthy subjects (mean age 27.9 years +/- 6.2 years) and 15 mature, healthy subjects (mean age 65.2 years +/- 13.7 years). In addition, measurements were taken of the lamina cribrosa in 12 of the volunteers from each subject group (mean age 27.1 +/- 6.3 years and 64.8 +/- 13.2 years respectively). Using a 10 x 10 pixel measurement frame, blood flow readings were obtained at a predetermined position on the retina, neuroretinal rim and lamina cribrosa. Student's two-tailed unpaired t-tests were used to compare measures of blood flow, volume and velocity between the two subject groups (P < 0.05). In addition, linear regression analysis was used to assess the relationship between age and blood flow, volume and velocity at the retina, neuroretinal rim and lamina cribrosa. RESULTS: Retinal blood volume measured at the retina was significantly lower in the mature compared with the young subject group (P = 0.01). Mature subjects also exhibited reduced blood flow and velocity at the neuroretinal rim (P = 0.01 for both parameters) and lamina cribrosa (P = 0.008 and P = 0.01 respectively). Regression analysis revealed negative trends for all blood flow parameters in each of the anatomical areas with advancing age. Significant negative correlations were obtained for retinal blood volume (r = -0.455, P < 0.05), neuroretinal rim blood velocity (r = -0.359, P < 0.05) and lamina cribrosa blood volume (r = -0.475, P < 0.05). CONCLUSION: Capillary blood flow in the retina, neuroretinal rim and lamina cribrosa decreases with advancing age. This may be of consequence in the progression of chronic ocular diseases such as glaucoma, and should be considered in the longitudinal determination of change in disease monitoring.


Subject(s)
Aging/physiology , Optic Disk/blood supply , Retinal Vessels/physiology , Sclera/blood supply , Adult , Aged , Blood Flow Velocity/physiology , Blood Volume/physiology , Capillaries/physiology , Female , Humans , Laser-Doppler Flowmetry/methods , Male , Middle Aged , Regression Analysis
14.
Front Biosci ; 6: B10-6, 2001 Sep 01.
Article in English | MEDLINE | ID: mdl-11532615

ABSTRACT

A small subset of patients infected with Borrelia burgdorferi (Bb) does not produce Bb specific antibody. Our research provides additional evidence of a genetic predisposition for seronegativity in some individuals with Lyme disease. Because human leukocyte antigen (HLA) class II, a heterodimeric glycoprotein, plays an essential role in the regulation of antibody production, we investigated the difference in HLA genes between seropositive and seronegative patients with Lyme disease (LD). Our results show that HLA-DR7 was associated with anti-Bb antibody production. Nine out of the 22 seropositive LD patients (40.9%) had HLA-DRB1*0701, *0703, *0704 (HLA-DR7); only 1 out of the 18 seronegative LD patients (5.6%) had HLA-DR7 (odds ratio (OR)=11.8, P=0.0126). HLA-DRB1*01021 and HLA-DRB1*0101, *0104, *0105 (HLA-DR1) contributed negatively to anti-Bb antibody production. Seven of 18 seronegative LD patients had HLA-DR1, only 1 of 22 seropositive LD patients had HLA-DR1 (38.9% vs. 4.5%, OR=13.4, P=0.0138). These results suggest that the presence and or lack of production of specific antibody to Bb infection may be associated with particular HLA specificities of the Class II.


Subject(s)
Antibodies, Bacterial/blood , Borrelia burgdorferi/immunology , HLA Antigens/genetics , Lyme Disease/genetics , Adult , Aged , Aged, 80 and over , DNA/genetics , Enzyme-Linked Immunosorbent Assay , Female , Gene Frequency , Genotype , HLA-DR Antigens/genetics , Humans , Lyme Disease/blood , Lyme Disease/microbiology , Male , Middle Aged
15.
Biochem J ; 355(Pt 2): 373-9, 2001 Apr 15.
Article in English | MEDLINE | ID: mdl-11284724

ABSTRACT

Homology models of the active site of cytochrome P450 2D6 (CYP2D6) have identified phenylalanine 481 (Phe(481)) as a putative ligand-binding residue, its aromatic side chain being potentially capable of participating in pi-pi interactions with the benzene ring of ligands. We have tested this hypothesis by replacing Phe(481) with tyrosine (Phe(481)-->Tyr), a conservative substitution, and with leucine (Phe(481)-->Leu) or glycine (Phe(481)-->Gly), two non-aromatic residues, and have compared the properties of the wild-type and mutant enzymes in microsomes prepared from yeast cells expressing the appropriate cDNA-derived protein. The Phe(481)-->Tyr substitution did not alter the kinetics [K(m) (microM) and V(max) (pmol/min per pmol) respectively] of oxidation of S-metoprolol (27; 4.60), debrisoquine (46; 2.46) or dextromethorphan (2; 8.43) relative to the respective wild-type values [S-metoprolol (26; 3.48), debrisoquine (51; 3.20) and dextromethorphan (2; 8.16)]. The binding capacities [K(s) (microM)] of a range of CYP2D6 ligands to the Phe(481)-->Tyr enzyme (S-metoprolol, 22.8; debrisoquine, 12.5; dextromethorphan, 2.3; quinidine, 0.13) were also similar to those for the wild-type enzyme (S-metoprolol, 10.9; debrisoquine, 8.9; dextromethorphan, 3.1; quinidine, 0.10). In contrast, the Phe(481)-->Leu and Phe(481)-->Gly substitutions increased significantly (3-16-fold) the K(m) values of oxidation of the three substrates [S-metoprolol (120-124 microM), debrisoquine (152-184 microM) and dextromethorphan (20-31 microM)]. Similarly, the K(s) values of the ligands to Phe(481)-->Leu and Phe(481)-->Gly mutants were also increased 3 to 10-fold (S-metoprolol, 33.2-41.9 microM; debrisoquine, 85-90 microM; dextromethorphan, 15.7-18.8 microM; quinidine 0.35-0.53 microM). However, contrary to a recent proposal that Phe(481) has the dominant role in the binding of substrates that undergo CYP2D6-mediated N-dealkylation routes of metabolism, the Phe(481)-->Gly substitution did not substantially decrease the capacity of the enzyme to N-deisopropylate metoprolol (wild-type, 1.12 pmol/min per pmol of P450; Phe(481)-->Gly, 0.71), whereas an Asp(301)-->Gly substitution decreased the N-dealkylation reaction by 95% of the wild-type rate. Overall, our results are consistent with the proposal that Phe(481) is a ligand-binding residue in the active site of CYP2D6 and that the residue interacts with ligands via a pi-pi interaction between its phenyl ring and the aromatic moiety of the ligand. However, the relative importance of Phe(481) in binding is ligand-dependent; furthermore, its importance is secondary to that of Asp(301). Finally, contrary to predictions of a recent homology model, Phe(481) does not seem to have a primary role in CYP2D6-mediated N-dealkylation.


Subject(s)
Cytochrome P-450 CYP2D6/metabolism , Phenylalanine/metabolism , Alkylation , Catalysis , Cytochrome P-450 CYP2D6/chemistry , Cytochrome P-450 CYP2D6/genetics , Debrisoquin/pharmacokinetics , Dextromethorphan/pharmacokinetics , Kinetics , Metoprolol/pharmacokinetics , Mutagenesis, Site-Directed , Oxidation-Reduction , Substrate Specificity
17.
Appl Neuropsychol ; 6(1): 12-8, 1999.
Article in English | MEDLINE | ID: mdl-10382566

ABSTRACT

This study examined the relation between complaints of memory disturbance and measures of mood and memory functioning in 55 patients with serological evidence of late-stage Lyme Borreliosis (LB). Patients completed the Self-Ratings of Memory Questionnaire (SRMQ) and the Beck Depression Inventory. Memory functioning was assessed with the California Verbal Learning Test. Depressed patients exhibited more frequent complaints of memory disturbance on the SRMQ, although their pattern of responses did not differ from nondepressed patients. There was a significant correlation between subjective memory ratings and self-reported depression (Spearman rho = -.57, p < .001). No relation was observed between subjective memory ratings and objective memory performance. The results indicate subjective complaints of more severe memory disturbance in patients with LB and depression. Particular attention should be paid to the assessment of depression and subjective symptoms of memory disturbance when administering neuropsychological tests of memory functioning in patients with LB.


Subject(s)
Depressive Disorder/diagnosis , Depressive Disorder/etiology , Lyme Disease/complications , Lyme Disease/psychology , Memory Disorders/diagnosis , Memory Disorders/etiology , Adult , Aged , Borrelia Infections/complications , Female , Humans , Lyme Disease/parasitology , Male , Middle Aged , Neuropsychological Tests , Severity of Illness Index , Surveys and Questionnaires
18.
Appl Neuropsychol ; 6(1): 33-8, 1999.
Article in English | MEDLINE | ID: mdl-10382569

ABSTRACT

Although subjective complaints of word finding and naming deficits are commonly reported by patients with Lyme Borreliosis (LB), the existence of these disturbances has not been thoroughly investigated. Forty-four patients with LB and 43 healthy controls were administered a symptom questionnaire, the Boston Naming Test (BNT), the Controlled Oral Word Association Test (COWAT), and a series of category naming tasks. LB patients had a higher rate of complaints of word-finding disturbance (55% vs. 14%). Lower mean scores were observed on the BNT, but not on the COWAT, nor on category naming tasks. Thirty-six percent of the LB sample exhibited BNT scores in the impaired range. BNT scores in this group were correlated with a measure of memory retrieval, but not with verbal fluency indexes. There was no relation between naming scores and depression. LB patients exhibit impairments in word finding that appear to be secondary to a generalized retrieval deficit.


Subject(s)
Cognition Disorders/diagnosis , Cognition Disorders/etiology , Lyme Disease/complications , Neuropsychological Tests , Adult , Borrelia Infections/complications , Enzyme-Linked Immunosorbent Assay , Female , Humans , Lyme Disease/parasitology , Male , Surveys and Questionnaires
19.
ASAIO J ; 45(5): 450-4, 1999.
Article in English | MEDLINE | ID: mdl-10503624

ABSTRACT

This article describes a prototype continuous flow ventricular assist device (CFVAD3) supported in magnetic bearings. The VAD is a small centrifugal four bladed pump. The pump's geometry is explained. The CFVAD3 is the first compact VAD completely supported in magnetic bearings. The magnetic bearings are composed of an inlet side actuator divided into eight pole sets, and an outlet side actuator, also divided into eight pole sets. The pump operating performance was tested and found to be within the design flow rate of up to 9 L/min, and head up to 170 mm Hg for human circulatory support. Magnetic bearing operation out of center positions under various operating orientations were measured and found to be < 1/6 of the bearing clearance, well within specifications. The expected magnetic bearing power loss has been calculated at approximately 6.5 watts.


Subject(s)
Heart-Assist Devices , Magnetics , Humans
20.
Artif Organs ; 23(8): 792-6, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10463509

ABSTRACT

This article presents the performance test results of the CFVAD3 continuous flow blood pump in an artificial human circulation system. The CFVAD3 utilizes magnetic bearings that support a thin pancake impeller, the shape of which allows for a very compact pump whose total axial length is less than 5 cm with a radial length of about 10 cm. This gives a total volume of about 275 cc. The impeller itself has 4 vanes with a designed operating point of 6 L/min at 100 mm Hg of differential pressure and 2,000 rpm. The advantages of magnetic bearings, such as large clearance spaces and no mechanical wear, are elaborated upon. Furthermore, bearing model parameters such as load capacity and current gains are described. These parameters in conjunction with the operating conditions during testing are then used to estimate the fluid forces, stiffness, and damping properties while pumping. Knowledge of these parameters is desirable because of their effects on pump behavior. In addition, a better plant model will allow more robust control algorithms to be devised that can boost pump performance and reliability.


Subject(s)
Heart-Assist Devices , Equipment Design , Humans , Magnetics , Models, Cardiovascular , Models, Structural , Rheology
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