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PubMed2006

Genealogy of wine grape cultivars: "Pinot" is related to "Syrah".

Since the domestication of wild grapes ca 6000 years ago, numerous cultivars have been generated by spontaneous or deliberate crosses, and up to 10 000 are still in existence today. Just as in human paternity analysis, DNA typing can reveal unexpected parentage of grape cultivars. In this study, we have analysed 89 grape cultivars with 60 microsatellite markers in order to accurately calculate the identity-by-descent (IBD) and relatedness (r) coefficients among six putatively related cultivars from France ("Pinot", "Syrah" and "Dureza") and northern Italy ("Teroldego", "Lagrein" and "Marzemino"). Using a recently developed likelihood-based approach to analyse kinship in grapes, we provide the first evidence of a genetic link between grapes across the Alps: "Dureza" and "Teroldego" turn out to be full-siblings (FS). For the first time in grapevine genetics we were able to detect FS without knowing one of the parents and identify unexpected second-degree relatives. We reconstructed the most likely pedigree that revealed a third-degree relationship between the worldwide-cultivated "Pinot" from Burgundy and "Syrah" from the Rhone Valley. Our finding was totally unsuspected by classical ampelography and it challenges the commonly assumed independent origins of these grape cultivars. Our results and this new approach in grape genetics will (a) help grape breeders to avoid choosing closely related varieties for new crosses, (b) provide pedigrees of cultivars in order to detect inheritance of disease-resistance genes and (c) open the way for future discoveries of first- and second-degree relationships between grape cultivars in order to better understand viticultural migrations.

Alleles↗

PubMed1998

Comparison of HPLC, capillary electrophoretic and direct spectrofluorimetric methods for the determination of temoporfin-poly(ethylene glycol) conjugates in plasma.

High-performance liquid chromatographic (HPLC), capillary electrophoretic (CE) and direct spectrofluorimetric methods for the determination of temoporfin-poly(ethylene glycol) 2000 conjugate (m-THPC-PEG 2000) in plasma are described and compared. m-THPC-PEG 2000 in plasma was quantitatively extracted (recovery 101-107%) with CH3OH-DMSO (4 + 1 v/v). The supernatant after centrifugation was used for HPLC, CE or direct spectrofluorimetric determination. The major drawback of the HPLC method was that it gave a broad and split peak even under gradient elution conditions, resulting in difficulty in detection and quantification. This is because m-THPC-PEG 2000 consists of a group of compounds with an average molecular mass of approximately 8680 Da owing to the wide molecular mass distribution of PEG 2000 used in the synthesis of the drug. m-THPC-PEG 2000 gave a single and relatively sharp peak when separated by CE with sodium tetraborate buffer (pH 9.45) in the presence of sodium dodecyl sulfate as the running buffer. However, this method lacks the necessary sensitivity for detecting the drug in plasma extract because of the limited sample volume that can be injected. Direct spectrofluorimetry is the method of choice because of its simplicity, specificity and sensitivity. Using an excitation wavelength of 423 nm and the specific emission maximum of 657 nm, the fluorescence intensity could be sensitively measured. The calibration curve constructed by plotting fluorescence intensity against concentration was linear within the range 1.32-1056 ng ml-1. The detection limit (S/N = 3) was 1.32 ng ml-1 and the limit of quantification (S/N = 10) was 2.24 ng ml-1. The precision and reproducibility were assessed by repeated analysis (n = 24) of spiked plasma samples at 350.8 and 699.3 ng ml-1. The RSD was 4.5% and 1.6%, respectively.

Adjuvants, Pharmaceutic↗

PubMed1998

Determination of alternariol in tomato paste using solid phase extraction and high-performance liquid chromatography with fluorescence detection.

Alternaria spp. produce a wide variety of toxic metabolites with different chemical structures. Tomato products have been considered a likely source of Alternaria toxins in the human diet because Alternaria is an important spoilage mold of tomatoes. A new method for the determination of these mycotoxins in tomato paste, involving solid phase cartridges for extraction before HPLC fluorescence detection with a reversed phase column and isocratic elution, was developed. The method was demonstrated to be linear in the range 5.2-196 ppb of alternariol (AOH) in tomato paste. Good recoveries were obtained for AOH at all levels assayed (minimum 77.2%). The detection limit of the AOH toxin in real samples of tomato paste was low, 1.93 ppb. The precision of the method was demonstrated with a good repeatability (RSD = 2.98%) and reproducibility (RSD = 9.35%).

Calibration↗

PubMed1976

Blood pressure and heart rate response to isometric exercise and mental arithmetic in normotensive and hypertensive subjects.

1. Sustained hand-grip exercise and mental arithmetic were performed by normal and hypertensive subjects. Blood pressure and heart rate were recorded with a device which allows blind and unbiased measurements, based on the conventional cuff method. 2. Both stimuli caused increases in heart rate and systolic and diastolic blood pressure, which were greater for isometric exercise than for mental arithmetic. 3. Normal females had a greater response to repeated exercise, and had a smaller systolic pressure elevation during mental arithmetic than the other groups. 4. Repeated testing showed good reproducibility in normal subjects.

Adult↗

PubMed1995

Comparison of bio-impedance spectroscopy and multi-frequency bio-impedance analysis for the assessment of extracellular and total body water in surgical patients.

1. Measurements of extracellular and total body water provide useful information on the nutritional status of surgical patients and may be estimated from whole-body bio-impedance measurements at different frequencies. 2. Resistance and reactance were measured at 50 frequencies from 5kHz to 1MHz in 29 surgical patients (17 males, 12 females) with a wide range of extracellular to total body water ratios. 3. A fit to the spectrum of reactance versus resistance data gave predicted resistances at frequencies zero and infinity. Values of extracellular and total body water determined by this bio-impedance spectroscopy technique were regressed against values obtained from radioisotope dilution. The standard errors of the estimate were 1.8931 and 3.2591 respectively. 4. Resistance indices (height2/resistance) at selected frequencies gave the highest correlations with extracellular and total body water at 5kHz and 200kHz respectively, and prediction equations derived from multiple stepwise regressions also showed these to be the optimum frequencies. The standard errors of the estimate for this multi-frequency bio-impedance analysis method were 1.9371 and 2.6061 for extracellular and total body water respectively. 5. To assess the ability of the two methods to measure changes in extracellular and total body water, reproducibility was assessed from repeat measurements 10 min apart in a subgroup of 15 patients. Bio-impedance spectroscopy gave mean coefficients of variation for extracellular and total body water of 0.9% and 3.0% respectively. For multi-frequency bio-impedance analysis the corresponding coefficients of variation were 0.9% and 0.6%. 6. It is concluded that a simple impedance analyser operating at only two frequencies compares favourably with the more complex spectroscopy technique for the determination of extracellular and total body water in surgical patients.

Biometry↗

PubMed2000

In vivo sequential study of skeletal muscle capillary permeability in diabetic rats: effect of anthocyanosides.

Alterations in the capillary filtration of macromolecules are well documented in diabetic patients and experimental diabetes. Various flavonoids including anthocyanosides and ginkgo biloba extracts have been shown to be effective against experimentally induced capillary hyperfiltration. The aim of the present study was to test the effects of anthocyanosides on capillary filtration in diabetic rats. For this purpose, we have validated the use of our previously described in vivo method for measurement of the capillary filtration of albumin (CFA) in rats. Male Wistar rats with streptozotocin (STZ)-induced diabetes were randomized in 3 groups to receive either ginkgo biloba (group A), Vaccinium myrtillus (group B), or no treatment (group C). The isotopic test of CFA consisted of intravenously injecting 99mtechnetium-labeled albumin, inducing venous compression on a hindquarter, and measuring radioactivity externally on the limb before, during, and after removal of venous compression. After removal of the tourniquet, the radioactivity curve decreased. Interstitial albumin retention (AR) and the ratio of the amplitudes of the low- and high-frequency peaks (LF/HF ratio), an index of lymphatic function obtained by the fast Fourier transform of the last part of the radioactivity curve, were calculated. In STZ-treated animals, the isotopic test was performed at a mean age of 97 days (time 1) and after 6 weeks (time 2) and 12 weeks (time 3) of treatment, ie, 6 and 12 weeks after time 1. At time 1, AR was significantly higher in the 3 diabetic groups than in the control rats, without a significant difference between these groups. In group B, AR decreased significantly (P = .015) at times 2 and 3. In group C, AR increased significantly (P < .0005) from time 1 to time 3. In group A, AR increased slightly (NS) between time 1 and time 3. In groups A and C, the LF/HF ratio significantly increased with time (P < .0005) and the levels at time 3 were significantly higher versus control rats (P < .0001). In group B, the LF/HF ratio remained unchanged from time 1 to time 3 and similar to the values found in the control rats. In conclusion, these data show that (1) this new in vivo noninvasive method can be used to study CFA in skeletal muscle in diabetic rats, (2) it is reproducible and may be repeated over several months to evaluate spontaneous microcirculatory changes, and (3) anthocyanosides appear to be effective in preventing the increase in CFA and the failure of lymphatic uptake of interstitial albumin in diabetic animals.

Animals↗

PubMedDate not supplied

Carotid artery blood flow during premanipulative testing.

BACKGROUND: Cervical manipulation is used millions of times every year. Concern about cerebrovascular accidents (CVAs) is common, but actual cases are rarely reported. Premanipulative tests are presumed to identify patients at risk of CVA. In an earlier study we found no significant changes in the vertebral artery blood flow of patients with a positive premanipulative test with different head positions. Consequently, we questioned whether there is a role for premanipulative testing to identify patients at risk of CVAs. OBJECTIVE: The aim of this study was to examine whether instead, blood flow velocity in the internal carotid arteries changes with head position in patients with a positive premanipulative test, potentially giving contraindication to cervical manipulation. METHODS: In a prospective study private practicing chiropractors from 3 Danish counties referred patients with a positive premanipulative test for an examination of cervical artery blood flow. Premanipulative testing was performed by an experienced chiropractor, and flow velocities were measured in both vertebral and internal carotid arteries by color duplex sonography at a university hospital vascular laboratory. RESULTS: A total of 11 consecutive patients with a positive premanipulative test were referred. Two of these were excluded because we could not reproduce any symptoms at repeat premanipulative testing before the vascular examination. In the remaining 9 patients we found no significant difference with different head positions in peak flow velocity or time-averaged mean flow velocity in the internal carotid arteries. Blood flow did not cease in 1 single patient despite a positive premanipulative test in all. CONCLUSION: It appears that a positive premanipulative test is not associated with a change in peak flow velocity or time-averaged mean flow velocity in either the carotid or the vertebral arteries. If premanipulative testing is used solely for the detection of vascular insufficiency as a potential substrate for CVAs after cervical manipulation, we believe that premanipulative testing is of little clinical value.

Adult↗

PubMed1993

Photostimulation using caged glutamate reveals functional circuitry in living brain slices.

An approach for high-spatial-resolution mapping of functional circuitry in living mammalian brain slices has been developed. The locations of neurons making functional synaptic connections to a single neuron are revealed by photostimulation of highly restricted areas of the slice (50-100 microns in diameter) while maintaining a whole-cell recording of the neuron of interest. Photostimulation is achieved by bathing brain slices in a molecularly caged form of the neurotransmitter glutamate [L-glutamic acid alpha-(4,5-dimethoxy-2-nitrobenzyl) ester], which is then converted to the active form by brief pulses (< 1 ms in duration) of ultraviolet irradiation. Direct activation of receptors on recorded neurons in rat hippocampus and ferret visual cortex demonstrates that photostimulation is reliable and reproducible and can be repeated at the same site at least 30 times without obvious decrement in neuronal responsiveness. Photostimulation of presynaptic neurons at sites distant to the recorded neuron evoked synaptic responses in hippocampal and cortical cells at distances of up to several millimeters from the recorded neuron. Stimulation of 25-100 distinct presynaptic sites while recording from a single postsynaptic neuron was easily achieved. Caged glutamate-based photostimulation eliminates artifacts and limitations inherent in conventional stimulation methods, including stimulation of axons of passage, desensitization, and poor temporal resolution of "puffer" pipettes, and current artifacts of iontophoretic application. This approach allows detailed physiological investigation and manipulation of the complex intrinsic circuitry of the mammalian brain.

6-Cyano-7-nitroquinoxaline-2,3-dione↗

PubMed2000

P2Y(2) receptor stimulation increases tear fluid secretion in rabbits.

PURPOSE: The purinergic P2Y(2) receptor agonists stimulate active Cl-transport across the excised rabbit conjunctival tissue in vitro. We determined whether UTP or ATP could increase the tear volume and change tear fluid composition in normal rabbits in vivo. METHODS: Fifty mL was applied to rabbit eyes of UTP, ATP at concentrations of 0.1, 0.3, 1, 3, 8.5% (1.8-154 mM) or saline. A modified Schirmer test with topical anesthesia was performed 5, 15, 30 and 60 min after the instillation. In studies lasting 30 days, 50 microL of 0.5% UTP was applied 6 times a day for 4 weeks. Tear samples were collected from the conjunctival sac with a glass microcapillary. The protein profile of the tear fluid was analyzed by SDS-polyacrylamide gel electrophoresis and total protein was measured with the Bradford assay. The Easy-Titer rabbit IgG assay kit was used for the determination of immunoglobulin G (IgG). RESULTS: UTP had dose-dependent stimulatory effects on tear secretion. It maximally increased tear secretion about 4-fold 15 min after its application. Similar effects were obtained with ATP. Repeated treatment with UTP reproducibly increased tear volume. Furthermore, UTP did not decrease total protein and IgG concentration in tear fluid and it had no effect on the protein profile. CONCLUSION: These data indicate that activation of P2Y(2) receptor increases tear fluid secretion accompanied with some proteins in normal rabbits. The purinergic agonists, UTP and ATP, have potential therapeutic value in the treatment of dry eye.

Adenosine Triphosphate↗

PubMed1975

Sulfur dioxide and tracheobronchial clearance in man.

Tracheobronchial clearance was measured in nine healthy, nonsmoking adults. Technetium Tc 99m albumin aerosol (mass median diameter, 3 mu; geometric standard deviation, 1.6) was inhaled as a bolus under controlled conditions to achieve reproducible deposition in large airways. Each subject was studied in three seperate three-hour experiments: twice under control conditions and once exposed to 5 ppm sulfur dioxide (pollutant exposure after aerosol inhalation). Lung retention of activity was measured using a gamma camera interfaced to a data storage and retrieval system. The study showed that (1) Both deposition and clearance were highly reproducible in individuals in repeat control studies. (2) Acute exposure to 5 ppm sulfur dioxide had no significant effect (P greater than .05) on mucocillary clearance in resting healthy subjects, except perhaps for a small transient change (P=.05) after one hour. (3) Pulmonary function tests showed a decrease in maximal midexpiratory flow (P less than .01) but no other significant changes.

Adult↗

PubMed1999

Monitoring spinal cord motor and somatosensory evoked potentials in anesthetized primates.

Monitoring Motor Evoked Potential (MEP) to Transcranial Stimulation (TMS) monitoring (MEP) is a growing technique to assess motor function under anesthesia. The following primate study was conducted to analyze the non-myogenic spinal motor and sensory volleys and to examine their reproducibility under nitrous oxide-methohexidone anesthesia. The traveling periodic spinal descending MEP to TMS and ascending somatosensory (SEP) to posterior tibial nerve stimulation across the thoracic cord were recorded in 12 cynomolgus monkeys. Through a small T11-T12 laminotomy, an insulated stainless steel electrode was inserted into the epidural thoracic space. The potentials were analyzed under 50 vol% NO in O2 with methohexital (0.1-0.2 mg kg-1 min-1). A well-defined periodic TMS-MEPs and PTN-SEPs were recorded with high reproducibility and consistency in repeated trials under N2O-methohexital anesthesia. MEP tracing consisted of an initial peak (direct (D) wave), occurring at 2.43 (+/- 0.28) msec followed by subsequent five positive (indirect (I) waves). Spinal SEPs-MEPs were clearly defined, morphologically stable, and consistent over time under N2O-methohexitone anesthesia. The present primate study may set a model to monitor both modalities in anesthetized neurosurgical patients.

Anesthesia, General↗

PubMed2005

Analysis of nifursol residues in turkey and chicken meat using liquid chromatography-tandem mass spectrometry.

Nifursol (3,5-dinitrosalicylic acid (5-nitrofurfurylidene) hydrazide) is mainly used as a feed additive for the prevention of blackhead disease in turkeys. The objective of the present work was to establish information on nifursol residues in turkey and chicken meat. The analytical method was based on conversion of nifursol and its metabolites with an intact 3,5-dinitrosalicylic acid hydrazide (DNSH) side chain to the 2-nitrophenyl analogue of nifursol (NPDNSH) by treatment with dilute hydrochloric acid and 2-nitrobenzaldehyde. Nifuroxazide (salicylic acid (5-nitrofurfurylidene) hydrazide) added as an internal standard was converted to the 2-nitrophenyl analogue NPSH. After the addition of ammonia, proteins were precipitated with acetonitrile. Chromatographic separation was achieved on a C18 column and negative-ion electrospray ionization mass spectrometry was employed using m/z 183 and 226 (daughter ions of the NPDNSH phenolate ion m/z 374) for quantification and m/z 93 (daughter ion of the NPSH phenolate ion m/z 284) as a retention time reference. The decision limit (CCa) and detection capability (CCbeta) of the analytical method were 0.05 and 0.08 microg kg(-1), respectively. In the range 0.5-1 microg kg(-1), the repeatability, within-laboratory reproducibility and trueness were 8, 11 and -1%, respectively. A total of 37 samples of turkey meat and 16 samples of chicken meat were purchased at retail outlets in early spring, summer and winter 2003, and analysed for nifursol residues. No residues were found in the chicken samples, but nine of 18 samples of turkey meat collected in the spring had between 0.05 and 0.6 microg kg(-1) (average 0.25 microg kg(-1)) nifursol residues.

Animals↗

PubMed2006

Simultaneous determination of lincomycin and five macrolide antibiotic residues in honey by liquid chromatography coupled to electrospray ionization mass spectrometry (LC-MS/MS).

A sensitive and specific method based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), for the simultaneous determination of lincomycin and five macrolide antibiotics in honey, was developed and validated. The analytes were extracted with Tris buffer 0.1 M, pH 10.5, and cleaned-up by a single solid-phase extraction step on OASIS HLB column. The chromatographic separation of analytes was performed on a Synergi Hydro-RP reversed-phase column using a gradient programme of aqueous 0.01 M ammonium acetate, pH 3.5, and acetonitrile as the mobile phase, at a flow rate 0.25 ml min-1. The detection of analytes was achieved by positive ionization electrospray in multiple reaction-monitoring mode. Two characteristic transitions were monitored for each substance. The following analytical parameters were validated according to the guidelines laid down by European Commission Decision 2002/657/EC (European Commission 2002): linearity, specificity, decision limit (CCalpha), detection capability (CCbeta), repeatability, within-laboratory reproducibility, recovery and ruggedness.

Animals↗

PubMed1995

Simulating efficiently the evolution of DNA sequences.

Two menu-driven FORTRAN programs are described that simulate the evolution of DNA sequences in accordance with a user-specified model. This general stochastic model allows for an arbitrary stationary nucleotide composition and any transition-transversion bias during the process of base substitution. In addition, the user may define any hypothetical model tree according to which a family of sequences evolves. The programs suggest the computationally most inexpensive approach to generate nucleotide substitutions. Either reproducible or non-repeatable simulations, depending on the method of initializing the pseudo-random number generator, can be performed. The corresponding options are offered by the interface menu.

Algorithms↗

PubMed1983

Characterization of cell proteins of Haemophilus ducreyi by polyacrylamide gel electrophoresis.

The whole-cell proteins of 105 clinical isolates of Haemophilus ducreyi from several geographic sources (North America, Africa, Asia, and Europe) were examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The protein profiles were reproducible and unaffected by repeated subculturing or age of culture. At least seven different subtypes were determined by proteins in the molecular weight range of 24,000-50,000. These proteins are located in the outer membrane of the cell, as determined by SDS-PAGE of the sarcosinate-insoluble membrane preparations of these strains. Thirteen isolates from a Winnipeg, Manitoba, Canada, outbreak of chancroid had identical patterns, suggesting a common origin. Although H ducreyi shares a number of proteins in common with other Haemophilus species, the protein profiles appear to be species specific. Heterogeneity in the protein composition of H ducreyi has provided a basis for subtyping, which could be of value in future epidemiologic studies.

Bacterial Proteins↗

PubMed1986

Pulmonary and systemic hemodynamic effects of nitrous oxide in infants with normal and elevated pulmonary vascular resistance.

The hemodynamic response to 50% nitrous oxide was studied in 12 sedated but responsive infants in the intensive care unit following repair of their congenital heart disease. One-half of the infants studied had an elevated pulmonary vascular resistance index (PVRI greater than 3.5 Wood units). During mechanical ventilation with a fractional inspired O2 concentration (FIO2) of 0.5, hemodynamic parameters were measured after equilibration with 50% nitrogen and then after 50% nitrous oxide. The sequence was repeated once to assure reproducibility of the responses. Average heart rate decreased by 9%, mean arterial blood pressure decreased by 12%, and cardiac index decreased by 13% in both the elevated and normal PVRI groups each time nitrous oxide was given. Although statistically significant, these changes would not generally be clinically important except in infants with severely compromised cardiovascular reserve. In contrast, pulmonary artery pressure and PVRI were not significantly changed by administration of 50% nitrous oxide in either the group with normal PVRI or the group with preexisting elevated PVRI. We conclude that while these mild depressant effects of nitrous oxide on systemic hemodynamics in infants are similar to those previously reported in adults, in infants nitrous oxide does not produce the elevations in pulmonary artery pressure and pulmonary vascular resistance seen in adults.

Age Factors↗

PubMed1991

Biochemical and electrophysiologic evidence that propofol enhances GABAergic transmission in the rat brain.

The influence of propofol, a new intravenous anesthetic agent, on brain gamma-aminobutyric acid (GABA)-ergic transmission has been investigated both in vitro and in vivo. In vitro, propofol, like benzodiazepines, 1) markedly enhanced 3H-GABA binding in cortical membrane preparations; 2) potentiated muscimol-induced stimulation of 36Cl- uptake in membrane vesicle preparations (the propofol potentiating effect was antagonized by bicuculline); and 3) inhibited 35S-TBPS binding to unwashed membrane preparations from rat cerebral cortex. Finally, propofol failed to displace 3H-flunitrazepam from its binding site, indicating that its site of action in brain is different from that of benzodiazepines. In vivo, the effect of propofol was studied using single-unit recording of the electrical activity of both nondopaminergic neurons in the pars reticulata of the substantia nigra (PR neurons) and of dopaminergic neurons in the pars compacta of the substantia nigra (DA neurons). PR neurons are known to be inhibited by GABA-mimetic drugs and benzodiazepines, whereas DA neurons are tonically inhibited by PR neurons. The intravenous administration of propofol, in a fat emulsion formulation, produced a brief dose-dependent inhibition of the firing rate of PR neurons. The dose producing 50% inhibition of the firing rate was calculated to be 1.2 +/- 0.1 mg/kg. The inhibitory effect lasted less than 5 min. Repeated injections of propofol reproduced the same inhibitory response, whereas continuous infusion (0.5 mg.kg-1.min-1) produced a persistent inhibition of neuronal firing. The inhibitory effect of propofol on PR neurons was potentiated by diazepam and reversed by picrotoxin and bicuculline but was not influenced by the benzodiazepine antagonist Ro 15-1788. These findings suggest that propofol exerts a GABA-mimetic action on PR neurons by acting on a site distinct from the benzodiazepine recognition site. Unlike benzodiazepines, propofol inhibited the firing rate of DA neurons with a potency proportional to its inhibitory effect on PR neurons. The inhibition of DA neurons was reversed by bicuculline and picrotoxin. The results suggest that propofol enhances the inhibitory control over DA neurons by strionigral GABAergic neurons.

Animals↗

PubMedDate not supplied

Assessment of circulating blood volume in calves with a total artificial heart.

Measurement of the circulating blood volume (CBV) is essential to a proper understanding of the hemodynamic performance of total artificial hearts (TAHs). Recently, the authors employed CBV measurements using indocyanine green dye in calves with a TAH. The advantages of this method over previous methods using radionuclides include simplicity, low cost, and the capability of repeated and frequent measurements. Reproducibility of the measurements was demonstrated in three normal calves with a relative standard deviation of 3.9 +/- 2.4%. CBV was measured in eight calves with the Cleveland Clinic-Nimbus TAH and compared with that of seven calves that underwent mitral valve replacement. Small standard deviations in pre operative values in both TAH and mitral valve replacement groups demonstrated the precision of CBV measurements. Although there was no change in CBV in the mitral valve replacement group, CBV in the TAH group increased to more than twice the pre operative value after 2 weeks. Although the right atrial pressure increased similarly after TAH implantation, there was no correlation (r = 0.08) between the right atrial pressure and CBV, which suggested a possible inaccuracy in estimating CBV from the right atrial pressure. A negative correlation between the hematocrit value and CBV suggested that hemodilution might be one of the causes of anemia observed in our TAH animals.

Animals↗