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The delivery to and utilization of oxygenated hemoglobin to the forearm muscles are key determinants of rock-climbing performance. Anthocyanin-rich New Zealand blackcurrant (NZBC) has been suggested to improve blood flow and may enhance forearm endurance performance. As such, a double-blind, randomized crossover design study with 12 participants performed submaximal intermittent contractions (at 40% maximal voluntary contraction) to failure after a 7-day intake of 600 mg/day NZBC extract or placebo. Minimum tissue saturation index (TSI%) was assessed during the contractions. During recovery, time to half recovery of TSI% and brachial artery blood flow were assessed. There was no difference in time to exhaustion between NZBC and placebo. Minimum TSI% was lower with NZBC extract (43 ± 8 vs. 50 ± 11 TSI%; p = .007; Cohen's d = 1.01). During recovery, there was no effect on brachial artery blood flow. However, time to half recovery was faster with NZBC (26 ± 17 vs. 42 ± 26 s; p = .001; Cohen's d = 1.3) following exhaustive contractions. Seven days of NZBC extract appears to improvemuscle oxygenation during and following contractions with no change in either arterial blood flow or forearm endurance performance. [ABSTRACT FROM AUTHOR]

Background: To observe the effect and mechanism of alpha-adrenergic receptor inhibitor phentolamine (PTL) in a rabbit model of acute pulmonary embolism (APE) combined with shock. Methods: Twenty-four New Zealand rabbits were randomly divided into sham operation group (S group, n = 8), model group (M group, n = 8) and PTL group (n = 8), the model of APE combined with shock was established. Mean pulmonary arterial pressure (MPAP), peripheral mean arterial pressure (MAP) and pulmonary circulation time were evaluated. The expression levels of α1 receptor, α2 receptor and their downstream molecules in pulmonary embolism (PE) and non-pulmonary embolism (non-PE) regions lung tissues were detected and compared, respectively. Results: In M group, α receptor-related signaling pathways were significantly activated in both PE and non-PE areas as expressed by up-regulated α1, α2 receptor and phospholipase C (PLC); the expression level of phosphorylated protein kinase A (p-PKA) was significantly down-regulated; myosin light chain kinase (MLCK) and α-smooth muscle actin (α-SMA) levels were up-regulated. PTL treatment significantly improved pulmonary as well as systemic circulation failure: decreased MPAP, restored blood flow in non-PE area, shortened pulmonary circulation time, increased MAP, and restored the circulation failure. PTL induced significantly down-regulated expression of α1 receptor and its downstream molecule PLC in both PE and non-PE area, the expression level of α2 receptor was also down-regulated, the expression level of p-PKA was significantly up-regulated. PTL treatment can inhibit both α1 and α2 receptor-related signaling pathways in whole lung tissues, and inhibit Ca2+ signaling pathways. The expression level of MLCK and α-SMA were significantly down-regulated. Compared with PE area, the changes of expression levels of α receptor and its downstream molecules were more significant in the non-PE region. Conclusion: In this model of APE combined with shock, the sympathetic nerve activity was enhanced in the whole lung, α1 and α2 receptor and their downstream signaling activation might mediate blood flow failure in the whole lung. PTL treatment can effectively restore pulmonary blood flow in non-PE area and improve pulmonary as well as systemic circulation failure possibly through down-regulating α1 and α2 receptor and their downstream signaling pathways. [ABSTRACT FROM AUTHOR]

Objective: The ocular vascular system plays an important role in preserving the visual function. Alterations in either anatomy or hemodynamics of the eye may have adverse effects on vision. Thus, an imaging approach that can monitor alterations of ocular blood flow of the deep eye vasculature ranging from capillary-level vessels to large supporting vessels would be advantageous for detection of early stage retinal and optic nerve diseases. Methods: We propose a super-resolution ultrasound localization microscopy (ULM) technique that can assess both the microvessel and flow velocity of the deep eye with high resolution. Ultrafast plane wave imaging was acquired using an L22-14v linear array on a high frequency Verasonics Vantage system. A robust microbubble localization and tracking technique was applied to reconstruct ULM images. The experiment was first performed on pre-designed flow phantoms in vitro and then tested on a New Zealand white rabbit eye in vivo calibrated to various intraocular pressures (IOP) – 10 mmHg, 30 mmHg and 50 mmHg. Results: We demonstrated that retinal/choroidal vessels, central retinal artery, posterior ciliary artery, and vortex vein were all visible at high resolution. In addition, reduction of vascular density and flow velocity were observed with elevated IOPs. Conclusion: These results indicate that super-resolution ULM is able to image the deep ocular tissue while maintaining high resolution that is comparable with optical coherence tomography angiography. Significance: Capability to detect subtle changes of blood flow may be clinically important in detecting and monitoring eye diseases such as glaucoma. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy of ultrasound-guided intra-articular injection of triptolide-loaded solid lipid nanoparticle (TP-SLN) for treatment of antigen-induced arthritis (AIA) in rabbits. Material and Methods: Knee joints of 33 New Zealand rabbits with AIA were injected intra-articularly with triptolide (TP: n = 7), TP-SLN (n = 7), betamethasone (BS: n = 7) and dimethyl sulfoxide (DMSO: n = 6). The remaining six rabbits were untreated as the control group. The injection therapy in intervention groups was initiated 1 week after the last immunization in order to avoid irreversible joint damage in the later induction. The ultrasonic scores of the joints were assessed based on synovitis, synovial blood flow and bone erosion. Meanwhile, the correlations of ultrasonic scores and pathological scores were determined. The efficacy and side effects of each group were determined by combining ultrasonic scores, pathological scores, behavior, appetite, weight, joint diameter, skin temperature and biochemical examination. Results: 1) Compared with the control group, the diameters of knee joints of the TP, TP-SLN and BS groups began to reduce 1 week after intra-articular injection (p < 0.01). 2) With the exception of the DMSO group, the interventions were effective in treating synovitis compared with the control group, with TP-SLN and BS being the best. The ultrasonic and pathological scores in synovitis of the TP group were lower than that of model group (Z = -2.726 and -2.530, p < 0.05). The ultrasonic scores differed significantly between BS group and TP-SLN group (Z = −2.17 and -2.360, respectively, p < 0.05) and pathological scores (Z = −2.687 and −2.082, respectively, p < 0.05). 3) Compared with the control group, the TP, BS and TP-SLN were all effective in treating synovial blood flow and bone erosion and there were no significant differences of ultrasonic and pathological scores among them (p > 0.05). The ultrasonic scores of synovial blood flow (Z = −3.033, −2.842, −3.277, p < 0.01) were lower than in the controls. The ultrasonic scores (Z = -2.948, -3.141, -3.210, p < 0.01) and pathological scores (Z = −2.216, −2.505, −2.505, p < 0.05) of bone erosion were also lower than in the model group.4) There were significant correlations between the ultrasonic and pathological scores of synovial inflammation and bone erosion (r = 0.832 and 0.859 respectively, p < 0.001). Conclusions: The therapeutic effect of TP-SLN on arthritis is better than that of TP, but there is no difference between BS and TP-SLN. Therefore, TP-SLN may be used as an alternative to BS in the treatment of rheumatoid arthritis in the future. The ultrasonic and pathological scores showed significant correlation in synovitis and bone erosion. Ultrasound can provide a useful assessment of synovitis in early arthritis. [ABSTRACT FROM AUTHOR]

Background: It is controversial to evaluate the function of hydronephrotic kidneys by renal dynamic imaging (RDI). Our aim was to study the features of renal dynamic imaging (RDI) at different stages after unilateral ureteral obstruction (UUO) and to investigate a method that could be reasonably used to evaluate renal function and predict renal functional recoverability. Methods: We made UUO models using fifteen adult New Zealand white rabbits and systematically observed the changes in kidney morphology, blood flow, radiotracer distribution and function by RDI. We then compared the differences in terms of imaging features between different periods and analyzed the relationship between blood flow and function in obstructed kidneys. Results: 1) Obstructed kidneys gradually became larger than preoperative kidneys and contralateral kidneys (P<0.05) and reached their peak size between days 42 and 56, after which they gradually got smaller in size. 2)The correlation between the blood perfusion of the obstructed kidney and the obstruction duration (r = 0.125, P = 0.045) was very weak. In the initial period of obstruction, the perfusion of the obstructed kidney significantly decreased, followed by a sharp rebound in later days, and then the perfusion declined again. The peak in blood perfusion was on day 7. 3) The uptake rate of the obstructed kidney drastically decreased in the early stage and became lower than that of the contralateral kidney and the kidney before the operation (P<0.05), after which uptake increased gradually; the peak was on day 28. After that, uptake gradually decreased. 4) The grading of the radiotracer distribution in obstructed kidneys was positively correlated with the obstruction duration (r = 0.975, P = 0.000), and a uniform renal distribution was an early feature of obstruction. 5) The blood perfusion of the obstructed kidney and its functioning frequently increased or decreased simultaneously, but sometimes there was also a mismatch. The peak of renal blood perfusion recovery occurred prior to the peak of renal function recovery. Conclusion: In different periods of severe UUO, the imaged features of obstructed kidneys were different. These features are beneficial for determining the degree of hydronephrosis and renal function and predicting renal functional recoverability. [ABSTRACT FROM AUTHOR]

Emerging evidence from human intervention trials indicates health benefits of consuming blackcurrant fruit, including improvements to cognitive performance, modulation of blood flow, regulation of blood glucose and inhibition of enzymes underpinning normal cognitive function. Of particular relevance is our previous demonstration of monoamine oxidase (MAO)-A and B inhibition after the consumption of a New Zealand "Blackadder" blackcurrant juice in humans. The current study uses a double-blind, placebo-controlled, randomised cross- over design to assess the pharmacodynamics of the effects on platelet MAO-B inhibition and associated substrates, plasma prolactin levels and blood glucose levels after consumption of a single serve of "Blackadder" blackcurrant juice standardised to 500 mg polyphenols. Eight healthy male (20-–35 years) participants completed the trial. Measurements were obtained at baseline 15, 30, 45, 60, 100, 120, 150, 180, 240 mins and 24 h post dose. A fast, absolute and reversible inhibition of blood platelet MAO-B (P < 0.001) and a significant but delayed reduction in plasma prolactin (P < 0.001) were observed following the consumption of "Blackadder" blackcurrant juice when compared to a placebo control. No interpretable changes in substrates of MAO or associated metabolites were seen. These data provide a clear time course of the reversible inhibition of MAO-B after the single consumption of a of New Zealand "Blackadder" blackcurrant juice standardised at 500 mg of polyphenols and, therefore, provide a therapeutic window on which to base future nutritional interventions. [ABSTRACT FROM AUTHOR]

Purpose: Blood flow to skeletal muscles and removal of metabolic by-products during a sport climb are essential to optimise performance and recovery. New Zealand blackcurrant (NZBC) extract has enhanced blood flow and performance in other exercise modalities. We examined the effect of NZBC extract on sport climbing performance and recovery.Methods: The study employed a double-blind, randomised, crossover design. Male sport climbers (n = 18, age 24 ± 6 years, height 179 ± 6 cm, mass 71.4 ± 7.8 kg, French grade 6a-8b) undertook 7 days supplementation of NZBC extract (600 mg day-1 CurraNZ™ containing 210 mg anthocyanins) or a placebo (PL). Climbing ability was assessed through hang time (HT), pull-ups and total climbing time (TCT) in 3 intermittent climbing bouts on a Treadwall M6 rotating climbing wall to exhaustion with 20 min recovery between climbs. Heart rate (HR), blood lactate (BL), forearm girth (FG) and hand grip strength (HGS) were recorded.Results: NZBC extract had no effect on pull-ups but provided a trend for higher HT and significantly improved TCT (+23%) compared to PL (-11%) over three climbs. HR, BL, FG and HGS all indicated that 20 min was insufficient for physiological recovery between the three climbing bouts indicating accumulative fatigue regardless of supplement condition.Conclusion: Despite indices of progressive fatigue across three bouts of climbing, NZBC extract facilitated not only a maintenance of TCT but an improved climbing endurance as compared with the PL condition. Blackcurrant anthocyanin-derived metabolites seem to affect physiological responses that facilitate sport climbing performance. [ABSTRACT FROM AUTHOR]

Abstract New Zealand Chinook salmon (Oncorhynchus tshawytscha) industry has great potential for growth and expansion. While production is relatively free of health problems, there is limited literature on haematology, and immunological tools to safeguard against possible future health threats. The current study aim was to characterise New Zealand farmed O. tshawytscha peripheral blood cellular composition, develop a micro-volume method to isolate peripheral blood mononuclear cells (PBMCs) and validate a microcapillary flow cytometry assay kit for PBMC cell count and viability assessment. We used light microscopy to characterise peripheral blood and PBMC cellular composition in combination with a flow cytometer Sysmex XT 2000i Haematology Analyser. ImageJ version 1.52 was used for cell size characterisation of freshly stained blood. The stability of PBMCs stained with the Muse® Cell Count and Viability Assay Kit and the Trypan blue assay stains were studied at 4 °C and 21 °C for 60 min; while the Muse® Cell Count and Viability Assay Kit was validated against the Trypan blue assay haemocytometer chamber to assess PBMC count and viability. Findings showed that O. tshawytscha smolt yearlings had total blood cell counts in the range of 1.9–2.7 × 106 μL−1. Differential cell counts revealed five cell types, comprising 97.18% erythrocytes, 2.03% lymphocytes, 0.67% thrombocytes, 0.09% monocytes, and unquantifiable neutrophils. Using micro-volumes of blood and Lymphoprep™, we successfully isolated fish PBMCs. Significantly, stained PBMCs remained stable for up to 45 min at 4 °C and 21 °C; while validation of the Muse® protocol showed that this microfluidic instrument delivered more accurate and precise viability results than the haemocytometer. The Muse® protocol is rapid, easy to use, has quick calibration steps, and is suitable for field use to facilitate onsite sample processing. These findings pave the way for future assessments of fish health and in vitro immunological studies in O. tshawytscha. Graphical abstract Image 1 Highlights • Salmon smolts peripheral blood total cell count was estimated at 2.3 × 106 μL−1. • Differential cell counts revealed five cell types dominated by 97.18% erythrocytes. • Fish PBMCs successfully isolated from a micro blood volume (<300 μL). • Isolated PBMCs were majorly composed of lymphocytes and monocytes. • Muse® Cell Analyser delivered accurate and precise results as the haemocytometer. [ABSTRACT FROM AUTHOR]

We examined effects of intake duration of New Zealand blackcurrant (NZBC) extract on cardiovascular responses during supine rest and moderate-intensity walking. Recreationally active men ( n  = 15, age: 24 ± 6 yr, BMI: 24.7 ± 4.3 kg·m -2 ) volunteered in a randomized, cross-over design. One metabolic equivalent (1-MET) was measured (3.97 ± 0.66 mL·kg -1 ·min -1 ) and an incremental walking test was performed to individualize speed at 4 ( n  = 3) or 5 ( n  = 12) METs for the 30-min walk (5.7 ± 0.7 km·hr -1 ). NZBC extract (210 mg of anthocyanins) was taken with breakfast for 7 and 14 days, with a 14-days washout. The final dose was ingested 2-hr before recording of the cardiovascular responses (Portapres Model-2). At rest, %changes at 7- and 14-days intake were observed for stroke volume (+6.8% (trend), p  = 0.065; +8.5%, p  = 0.012), cardiac output (+10.1%, p  = 0.007; +8.5%, p  = 0.013), total peripheral resistance (-12.0%, p  = 0.004; -13.1%, p  = 0.011), diastolic (-5.7%, p  = 0.045; -9.7%, p  = 0.015) and mean arterial pressure (-4.4%, p  = 0.040; -7.2%, p  = 0.029), but without intake duration effect. During walking, %changes at 7- and 14-days intake were observed for stroke volume (+7.7% (trend), p =  0.063; +9.9%, p =  0.006), cardiac output (+8.7%, p =  0.037; +10.1%, p  = 0.007), diastolic blood pressure (-6.2%, p =  0.042; -10.6%, p  = 0.001), and total peripheral resistance (-9.6%, p =  0.042; -13.5%, p  = 0.005) but without intake duration effect. During walking, %changes at 14-days were observed only for mean arterial pressure (-6.4%, p  = 0.018) and arterio-venous oxygen difference (-7.9%, p  = 0.019). NZBC extract affects cardiovascular responses at rest and during moderate-intensity exercise with 7- and 14-day intake. Only during moderate-intensity exercise, a longer intake of NZBC extract was required for an effect on some cardiovascular responses.

Seven-day intake of anthocyanins from New Zealand blackcurrant (NZBC) extract increased cardiac output and femoral artery diameter during a sustained submaximal isometric contraction. It is not known if there are intake duration effects by NZBC extract on the isometric contraction-induced cardiovascular responses. In a repeated measures design, male participants ( n  = 19, age: 26 ± 4 years) performed a 120-second submaximal (30%) isometric contraction of the knee extensors at baseline and following 1, 4 and 7-days intake of 600 mg·day -1 NZBC extract. During the 120-second submaximal isometric contraction, femoral artery diameter and cardiovascular responses were measured with ultrasound and beat-to-beat hemodynamic monitoring. Femoral artery was larger following 4-days (mean difference = 0.046 cm, 95% CI [0.012, 0.080], p  = 0.005) and 7-days (mean difference = 0.078 cm, 95% CI [0.034, 0.123], p  < 0.001) in comparison to baseline with no increase with 1-day intake. Systolic and diastolic blood pressure, heart rate and total peripheral resistance were not changed by NZBC extract at 1, 4 and 7-days intake. However, mean arterial pressure, stroke volume, cardiac output and total peripheral resistance were changed at time points during the isometric contraction following 7-days intake in comparison to 1-day intake of NZBC extract ( p  < 0.05). Alterations in femoral artery diameter and some cardiovascular responses during a submaximal sustained isometric contraction of the knee extensors are affected by the intake duration of New Zealand blackcurrant extract, with no effects by 1-day intake. Our observations suggest that the bioavailability of blackcurrant anthocyanins and anthocyanin-derived metabolites is required for days to alter the mechanisms for isometric-contraction induced cardiovascular responses.

Abstract: The aim of this proof-of-principle study was to assess an intraluminal expandable stent design using an existing cardiac stent. Intraluminal stents minimise the amount of suturing necessary when performing an end-to-end anastomosis. The stent is passed halfway through the lumen on each end of the vessel to be anastomosed and is expanded using a retrievable balloon. An adequately expanded stent holds the blood vessel ends in contact without the need for sutures. This method was tested on an end-to-end anastomosis performed on the carotid vessels of two New Zealand male rabbits. The vessels were patent with good blood flow at the end of 16 days. This method has a potential use in vascular, microvascular and luminal anastomoses within various sub-specialities of surgery. [Copyright &y& Elsevier]

(R,R)ZX-5 is a NO regulatory compound, which could significantly increase choroidal blood flow in New Zealand rabbit. The aim of this paper is to investigate the molecular mechanism of (R,R)ZX-5 promoting NO production. Besides this, we also investigated the antiangiogenic activity of (R,R)ZX-5. Analysis of Western blot showed that (R,R)ZX-5 up-regulated the expression of Akt, p-Akt (Thr473), eNOS and p-eNOS (Ser1177), down-regulated the expression of Cyclin D1 in human retinal endothelial cells and escalated the intracellular free Ca2+ concentration. Additionally, (R,R)ZX-5 inhibited the growth of blood vessels in the chick chorioallantoic membrane model. It is concluded that (R,R)ZX-5 promotes choroidal blood flow through PI3K/Akt-eNOS and Akt-Ca2+-eNOS pathways. Additionally, (R,R)ZX-5 can inhibit angiogenesis. [ABSTRACT FROM AUTHOR]

The article presents the results of a study which investigated the benefits of wearing a lower body compression garment for cycling time performance. An overview of related previous research is provided, detailing how the use of compression garments during recovery significantly increased subsequent force production. Details of the experiment protocol are also presented, including use of a single-blind crossover experiment.

The article discusses a study which investigated whether partial expander deflation exacerbates the adverse effects of radiotherapy in two-stage breast reconstruction. As part of the study, 18 New Zealand rabbits were divided into three groups, and metallic port integrated anatomic breast expanders of 250 cc were implanted on the back of each animal and controlled expansion was performed. The study concluded that expander deflation immediately prior to radiotherapy, may augment the adverse effects, especially in the lower expander pole.

Aim: Hyperhomocysteinemia was induced in rabbits using methionine. Ocular blood flow changes were examined by color Doppler ultrasonography (CDU). Materials and methods: Fifty New Zealand rabbits were divided into 5 groups. Groups 1-4 received one of the following chemicals: methionine only, methionine plus vitamin B6, methionine plus vitamin B12, or methionine plus folic acid. Controls received no chemicals. Serum homocysteine levels were measured on treatment days 1 and 60. Orbital vessels were examined by CDU on day 60. Results: In the 4 study groups, homocysteine levels were significantly elevated on day 60 compared to the levels on day 1 (P < 0.05). Elevations of homocysteine levels in group 1 were greater than those of groups 2 and 4 on day 60 (P < 0.05). When results of ocular blood flow changes were compared, no statistically significant difference was found based on flow velocities in the ophthalmic artery. Measurements from the ciliary artery revealed a statistically significant decrease in flow velocity in the study groups (P < 0.05). Conclusion: Using CDU, we found that flow velocities in the ciliary artery were decreased. This condition is attributed to atherosclerotic and thromboembolic alterations of the ocular vessels due to hyperhomocysteinemia. [ABSTRACT FROM AUTHOR]

The article discusses two experimental studies that were conducted to determine whether blood flow rate changes and/or red blood cell damage happens during red cell transfusion via a single blood filter. Measurements of flow rates of each red cell unit and saline were taken. Red blood cells were analyzed for hemoglobin, hematocrit, lactate dehydrogenase, potassium, hemolysis levels and red cell morphology. Findings show a decrease in hemolysis and lactate dehydrogenase levels but no evidence that red blood cell damage increases during transfusion.

The article discusses a study on the effects of ranolazine, an inhibitor of the late sodium current in myocytes, on myocardial infarct size and blood flow in ischemia/reperfusion in rabbits. According to the study which made use of male New Zealand white rabbits, ranolazine has no effect on regional blood flow. On the other hand, it found that size of myocardial infarct was reduced.

Purpose: The aim of this study was to investigate sympathetic influences on blood-flow velocity and resistance in the rabbit ophthalmic artery during the transition period from the light to the dark phase. Methods: Eight (8) New Zealand albino rabbits were entrained to a daily 12-h light and 12-h dark cycle. Blood-flow velocities in the ophthalmic artery were determined at −2 (baseline), 0, 2, and 4 h after the onset of darkness. Pulsed and color Doppler images of the ophthalmic artery were recorded using a 12-MHz linear ultrasound transducer. Resistive index of blood flow was calculated using the peak systolic velocity and the end diastolic velocity. Measurements of intraocular pressure (IOP) were taken, using a pneumatonometer at the same time points. Blood-flow velocity, resistive index, and IOP were also determined in the same rabbits after surgical decentralization of the ocular sympathetic nerves. Results: Compared with the baseline at −2 h, a significant increase in the resistive index of blood flow in the ophthalmic artery occurred at 2 and 4 h after the onset of darkness. Parallel elevations of IOP were observed. After the sympathetic decentralization, peak systolic and end diastolic velocities decreased and resistive indexes increased from the presurgical values in the ophthalmic artery. In the postsurgical rabbits, elevation of IOP was absent during the light-dark transition period. There was also no time-dependent increase of resistive index in the ophthalmic artery. Conclusions: During the light-dark transition period, resistance to blood flow in the rabbit ophthalmic artery increases in parallel to IOP elevation. The removal of sympathetic activities decreases blood-flow velocity, but increases blood-flow resistance. Like the endogenous elevation of IOP, the time-dependent increase of resistance to blood flow in the rabbit ophthalmic artery during the light-dark transition period depends upon, at least partially, ocular sympathetic activities. [ABSTRACT FROM AUTHOR]

Objectives: It has been shown that a hydroxyethylstarch solution significantly increases the aortic distensibility coefficient (ADC) as compared to other non-hydroxyethylstarch colloid solutions. In order to investigate whether the effect of hydroxyethylstarch on ADC is class-specific, we investigated the effect of two hydroxyethylstarch solutions (HES 200: Elohes® and HES 240: Hesteril®) on the ADC and compared them with two other colloid solutions: 5% albumin and fluid gelatin (Gelofusin®) in a rabbit model of acute isovolumic hemodilution. Methods: Twenty-eight male New Zealand white rabbits were anesthetized and randomly allocated to receive (n=7, each): albumin, hydroxyethylstarch-200, hydroxyethylstarch-240 and gelatin for acute isovolumic hemodilution by exchanging 13 ml.kg-1 body weight of blood with an identical volume of the test solution. Blood viscosity, mean arterial pressure, aortic blood flow and heart rate were measured and ADC was calculated. Results: All groups were comparable with respect to arterial pressure, heart rate and aortic blood flow velocity before and after isovolumic hemodilution. After hemodilution, ADC coefficient remained unchanged as compared with pre-hemodilution values with albumin, hydroxyethylstarch-240 and gelatin, whereas a sustained 3 fold increase was observed with hydroxyethylstarch-200. Conclusion: These results demonstrate that minor physicochemical differences between two hydroxyethylstarch solutions result in measurable differences in ADC and suggest that the clinical effects of colloids should probably be analyzed for each type of colloid and not for classes of colloids (e.g. hydroxyethylstarch or fluid gelatins). [ABSTRACT FROM AUTHOR]

We have assessed the effects of antigenic stimulation on the regional blood flow of the lymph node. In seventeen New Zealand white rabbits, the regional blood flow to the popliteal lymph nodes was determined using 9 and 15 μm microspheres at 16, 40, and 144 h following antigen administration. The regional blood flow in the resting lymph node measured with 15 μm spheres was 0.46±0.07 ml g-1 mm -1, with 9 μm spheres 0.26±0.03 ml g-1 min-1. There was a significant 'differential flow' (the difference in blood flow between the experimental and control nodes) measured with 15 μm spheres (P<005). This increase in blood flow was larger early (16 h) than late (144 h) following antigen administration (P < 0.01). There was significant (P < 0.05) 'shunt flow' (the difference in blood flow measured with 15 μm and 9 μm spheres) in the lymph node, with more shunting early (16 h) than late (144 h) following antigen administration. No significant shunting was seen in the kidney or thigh muscle. Thus, we have established: (1) a significant increase in blood flow following antigenic stimulus; (2) shunting of 9 μm microspheres in the resting popliteal lymph node; (3) increased shunting following antigenic stimulus; and (4) that the increase in nodal blood flow was, to a large extent, secondary to increased shunt flow. Both the increased blood flow and the shunting shortly after antigenic stimulus may be important in the evolution of the immune response. [ABSTRACT FROM AUTHOR]

Introduction: Aortopulmonary collateral (APC) flow is a common finding in the Fontan circulation. It has been suggested that these collaterals should be routinely embolised to reduce volume loading of the single ventricle. We aimed to assess the role of APC flow on the exercise capacity of patients with a Fontan circulation. Methods: As part of a Cross Sectional Study evaluating the Functional Outcomes of Fontan patients of Australia and New Zealand, patients with an extracardiac conduit or lateral tunnel Fontans were recruited. Patients with severe valve regurgitation or arch obstruction were excluded. Exercise capacity was measured by cardiopulmonary exercise testing. Each participant underwent a Cardiac MRI (Siemens 1.5T Aera) at rest and with supine exercise (Lode bicycle ergometer). Using standard MRI cine and flow assessment techniques ventricular volumes and flows were assessed. Cycling was briefly stopped (<30 seconds) for acquisition of data with breathhold during exercise stress. Collateral flow was derived from the difference between the ascending aortic and (total descending aorta and SVC flow). (AoA flow-(AoD+SVC flow). Results: Good quality data was obtained from 27 participants. Cardiac index increased from 3L/min/m2 on average at rest (+/-SD 0.81) to 4.4 L/min/m2(+/-SD 0.79; p=<0.001) at peak exercise and APC flow increased by 13% (+/-SD 47; p=0.06). APC during exercise flow corresponded to 13.3% of the ascending aortic flow on average (+/-SD 12.1). There was a nonsignificant positive correlation between APC flow at rest and % predicted VO2max (r=0.13; p=0.53). APC flow measured at peak exercise was associated with better exercise capacity (r=0.81, p=0.0016). There was no significant relationship between APC flow and ventricular volumes or cardiac index. Conclusion: Increased aortopulmonary collateral flow with exercise has a positive impact on the exercise capacity of patients with a Fontan circulation through augmentation of pulmonary blood flow and hence improved ventricular preload. [ABSTRACT FROM AUTHOR]