Mean Volume (mean + volume)

Distribution by Scientific Domains


Selected Abstracts


Intra-amniotic endotoxin accelerates lung maturation in fetal rabbits

ACTA PAEDIATRICA, Issue 1 2001
Kristina Bry
The hypothesis that endotoxin in amniotic fluid accelerates fetal lung maturation was tested. On day 25 of gestation, LPS (5 ,g/fetus) was injected intra-amniotically into one uterine horn of eight New Zealand white rabbits, whereas the contralateral amniotic sacs were injected with saline vehicle. The fetuses were delivered 48 h after LPS administration and their lungs were studied. One dam went into premature labor prior to the 48 h time point and was excluded from the study. Mean white cell counts in amniotic fluid and bronchoalveolar lavage fluid from LPS-treated fetuses were increased 3.2-fold (p= 0.04) and 9.9-fold (p= 0.04), respectively. Fetal weights and lung weights were not affected by LPS. Surfactant protein SP-A and SP-B mRNA expressions in LPS-treated fetuses were increased 2.3-fold (p= 0.03) and 1.4-fold (p= 0.04), respectively. Static lung compliance was increased in animals treated with LPS (p= 0.001). Lungs from LPS-treated animals had better aeration than those of controls. Mean volume of inflation-fixed lungs of LPS-treated fetuses was 1.7 times greater than that of controls (p= 0.03). Conclusion: Intra-uterine exposure to LPS increases surfactant protein expression and improves lung stability and aeration in preterm animals. [source]


Changes in adipocytes and dendritic cells in lymph node containing adipose depots during and after many weeks of mild inflammation

JOURNAL OF ANATOMY, Issue 6 2005
Dawn Sadler
Abstract The time course and cellular basis for inflammation-induced hypertrophy of adipose tissue were investigated over 20 weeks in mature male rats. Mild inflammation was induced by subcutaneous injection of 20 µg lipopolysaccharide into one hind-leg three times/week for 4 or 8 weeks, followed by up to 12 weeks ,rest' without intervention. Mean volume and frequency of apoptosis (TUNEL assay) were measured in adipocytes isolated from sites defined by their anatomical relations to lymph nodes, plus numbers of CCL21-stimulated lymph node-derived and adipose tissue-derived dendritic cells. Experimental inflammation increased dendritic cells and adipocyte apoptosis in the locally stimulated popliteal depot and the lymphoid tissue-associated regions of the contralateral popliteal and mesentery and omentum. Responses declined slowly after inflammation ended, but all measurements from the locally stimulated popliteal depot, and the omentum, were still significantly different from controls after 12 weeks rest. The locally stimulated popliteal adipose tissue enlarged by 5% within 4 weeks and remained larger than the control. We conclude that prolonged inflammation induces permanent enlargement, greater adipocyte turnover and increased dendritic cell surveillance in the adjacent adipose tissue and the omentum. The experiment suggests a mechanism for selective hypertrophy of lymphoid tissue-associated adipose tissue in chronic stress and inflammatory disorders, including impaired lymph drainage, Crohn's disease and HIV-associated lipodystrophy, and a link between evolutionary fitness, sexual selection and aesthetically pleasing body symmetry. It would be useful for further study of molecular mechanisms in inflammation-induced local hypertrophy of adipose tissue and development of specific therapies that avoid interference with whole-body lipid metabolism. [source]


Intratesticular arterial resistance and testicular volume in infertile men with subclinical varicocele

JOURNAL OF CLINICAL ULTRASOUND, Issue 8 2004
Nevbahar Akcar MD
Abstract Purpose The aim of this study was to evaluate whether intratesticular arterial resistance and testicular volume differed between infertile men with subclinical varicoceles and infertile men without varicoceles. Materials and Methods Fifty-eight infertile men were examined by gray-scale and color Doppler sonography for presence of varicocele, testicular volume, and arterial resistance. For men in the study group, mean testicular volume and resistance index (RI) in testes with varicoceles were compared with those in the contralateral testis by the paired t-test; statistical analyses between the study and control groups were performed by independent t-tests. Results Twenty-seven men had left-sided varicoceles (96% of which were subclinical), and 31 infertile men without varicoceles served as controls. Mean volumes of the right and left testes of study subjects were 14.8 ml and 14.6 ml, respectively, and in controls were 14.2 ml and 13.6 ml, respectively. Mean RI values for the right and left testes of study subjects were 0.61 and 0.58, respectively, and in controls were 0.61 and 0.58, respectively. There were no statistically significant differences in volume or RI, either between the right and left testes within patient groups or between the control and study groups' combined mean values. While the mean intertesticular volume differences for the study and control groups were 2.2 ml and 3.4 ml, respectively, the mean intertesticular RI differences were 0.04 and 0.07, respectively. These values also did not differ significantly between the 2 groups. Conclusions Subclinical varicocele is not associated with ipsilateral testicular atrophy, and does not affect the intratesticular arterial RI. © 2004 Wiley Periodicals, Inc. J Clin Ultrasound 32:389,393, 2004 [source]


Variability in the spawning habitat of Pacific sardine (Sardinops sagax) off southern and central California

FISHERIES OCEANOGRAPHY, Issue 6 2003
Ronald J. Lynn
Abstract The spatial pattern of sardine spawning as revealed by the presence of sardine eggs is examined in relation to sea surface temperature (SST) and mean volume backscatter strength (MVBS) measured by a 150 kHz acoustic Doppler current profiler (ADCP) during four spring surveys off central and southern California in 1996,99. Studies in other regions have shown that MVBS provides an excellent measure of zooplankton distribution and density. Zooplankton biomass as measured by survey net tows correlates well with concurrently measured MVBS. The high along-track resolution of egg counts provided by the Continuous Underway Fish Egg Sampler (CUFES) is a good match to the ADCP-based data. Large interannual differences in the pattern and density of sardine eggs are clearly related to the concurrently observed patterns of surface temperature and MVBS. The strong spatial relationship between sardine eggs and MVBS is particularly evident because of the large contrast in zooplankton biomass between the 1998 El Niño and 1999 La Niña. The inshore distribution of sardine spawning appears to be limited by the low temperatures of freshly upwelled waters, although the value of the limiting temperature varies between years. Often there is an abrupt offshore decrease in MVBS that is coincident with the offshore boundary of sardine eggs. Possible reasons for this association of sardine eggs and high zooplankton biomass include an evolved strategy that promotes improved opportunity of an adequate food supply for subsequent larval development, and/or adult nutrient requirements for serial spawning. Hence, the distribution of these parameters can be used as an aid for delineating the boundaries of sardine spawning habitat. [source]


Estimation of number of follicles, volume of colloid and inner follicular surface area in the thyroid gland of rats

JOURNAL OF ANATOMY, Issue 2 2005
M. L. Hartoft-Nielsen
Abstract Volume is an important variable in assessing the growth and involution of the thyroid gland. The functional unit in the thyroid is the follicle, which consists of thyrocytes surrounding colloid. The size of a follicle depends on the number of cells and the amount of colloid. These are interchangeable and vary according to biological activity. Direct measurements of these variables provide information on structures involved in thyroid hormone synthesis, storage and secretion, and also on changes at the morphological and functional levels. Stereological methods are developed to obtain information on three-dimensional structures from two-dimensional sections and to achieve information on an entire organ by examining a minor part of it. Full-grown male Sprague,Dawley rats were used to develop a set of methods relying on unbiased stereological principles to determine the number of follicles, the total volume of colloid and the inner follicular surface area in the thyroid gland. The total volume of colloid was positively correlated (P < 0.021) with the number of follicles and the inner follicular surface area (P < 0.002) but not to the mean volume of colloid in each follicle. Thus under physiological conditions an increase in the total volume of colloid is associated with an increased number of follicles with a constant size distribution rather than a larger volume of colloid in each follicle. This implies that under physiological conditions there is equilibrium in the size distribution of the volume of colloid in each follicle. [source]


Changes in immunological and virological parameters in HIV-1 infected subjects following leukapheresis

JOURNAL OF CLINICAL APHERESIS, Issue 2 2003
M.R. Boulassel
Abstract In order to assess immune responses during HIV-1 therapeutic immunization, a large number of blood mononuclear cells (PBMC) are needed. Clinical tolerance and safety, as well as changes in immunological and virological parameters, were assessed, following leukapheresis in HIV-1 infected subjects with CD4+ cell count >200 × 106/l. PBMC were collected using a Fenwal CS3000 cell separator in 29 subjects with mean CD4+ cell counts of 503 × 106/l (range 172,1,119) and viral load of 2.5 log10 copies/ml (range <1.7,5.4). Twenty-four (83%) subjects were on antiretroviral therapy while 5 (17%) were untreated. The blood volume processed was 7 L over a period of 3 hours. A mean value (± standard error) of 82 ± 26 × 109/l lymphocytes was collected by a single apheresis in a mean volume of 200 ± 1.8 ml, containing 9.0 ± 1.3 × 109/l CD4+ and 10.2 ± 1.3 × 109/l CD8+ cells. The leukapheresis procedures were well tolerated and no immediate or delayed side effects were observed within 90 days of follow-up. No changes from blood pre-leukapheresis values were detected for white blood cells, lymphocytes, monocytes, CD8+, CD34+, naive and memory CD4+ cell counts immediately after, 1 h, 7 days, or within 90 days after leukapheresis. However, absolute CD4+ cell counts and percentage significantly increased from pre-leukapheresis values after 1 h (530 ± 43 vs. 700 ± 75 cell × 106/l; 32.6 ± 1.6 vs. 36.9 ± 1.9%; P < 0.001 for both paired t -tests) before returning to pre-leukapheresis levels on day 7. No significant changes in viral load from pre-leukapheresis levels in treated or untreated subjects were detected at any time points. We conclude that leukapheresis in HIV-1 infected subjects with CD4+ cell counts >200 × 106/l is safe and induces a transient increase in the absolute and percentage of CD4+ cell count without enhancing viral replication. J. Clin. Apheresis 18:55,60, 2003. © 2003 Wiley-Liss, Inc. [source]


Invertebrate prey and predatory behaviour of the omnivorous African tortoise Kinixys spekii

AFRICAN JOURNAL OF ECOLOGY, Issue 1 2001
Adrian Hailey
Abstract Invertebrates form an important part of the diet in the omnivorous African tortoises of the genus Kinixys. Millipede prey of Kinixys spekii in Zimbabwe had a mean volume of 0.9 ml, and made up 64.7% of invertebrate food by volume; beetles made up most of the remainder and had a mean volume of 1.4 ml. The mean mass of invertebrate prey was 0.19% of tortoise mass, a similar value of relative prey mass to many insectivorous lizards. Tortoises preferentially attacked moving millipedes at or just behind the head, but predatory behaviour was otherwise unspecialized, with tortoises killing millipedes by ingesting them in pieces. Handling times of millipede prey varied significantly with relative prey mass, defensive behaviour, and direction of ingestion. The profitability (mass intake/handling time) of millipedes was maximal at a relative prey mass of 0.2%; the basis on which prey are selected is discussed. Résumé Les invertébrés constituent une grande part du régime alimentaire des tortues africaines omnivores du genre Kinixis. Les mille-pattes qui sont les proies de Kinixis spekii au Zimbabwe ont un volume moyen de 0,9 ml, et constituent 64,7% du volume des invertébrés qu'elles consomment; les coléoptères représentent à peu près le reste du volume, et ont un volume moyen de 1,4 ml. La masse moyenne des proies invertébrées était de 0,19% de la masse des tortues, une valeur semblable à la masse relative des proies de nombreux lézards insectivores. Les tortues attaquaient de préférence les mille-pattes en mouvement juste derrière la tête ou à la tête, mais à part cela, leur comportement de prédateur n'était pas spécialisé, les tortues tuant les mille-pattes et les mangeant par morceaux. Le temps de manipulation de la proie variait significativement en fonction de la taille relative du mille-pattes, de son comportement défensif et du sens de l'ingestion. La profitabilité (masse ingérée/temps de manipulation) des mille-pattes était maximale lorsque la masse relative de la proie était de 0,2%; on discute la base sur laquelle les proies sont choisies. [source]


Effects of matrix grain size on the kinetics of intergranular diffusion

JOURNAL OF METAMORPHIC GEOLOGY, Issue 8 2004
W. D. Carlson
Abstract A linear relationship exists between the mean volume of garnet porphyroblasts and the squared inverse of mean matrix grain diameter for six samples of garnetiferous mica quartzite with identical thermal histories and similar mineralogy and modes. This relationship accords with theoretical predictions of the dependence of intergranular diffusive fluxes on the volume fraction of grain edges that function as diffusional pathways during porphyroblast growth. The impact of matrix grain size is large: compared to a rock with a 1-mm matrix, a rock with a 10- ,m matrix would experience rates of diffusion-controlled porphyroblast growth that are 10 000 times faster, and characteristic length scales for chemical equilibration that are 100 times larger. Precursor grain sizes may therefore exert a major influence on crystallization kinetics. If matrix coarsening occurs during prograde reaction, a decrease in the volume fraction of diffusional pathways will tend to counteract the exponential thermal increase in diffusive fluxes. The impact of such matrix grain growth, although difficult to assess without firm knowledge of coarsening rates in polymineralic aggregates, might be significant for matrices finer than c. 100 ,m at temperatures above c. 500,600 °C, but is likely negligible for coarser grain sizes and lower temperatures. [source]


EFFECTS OF BITE SIZE ON THE SENSORY PROPERTIES OF VANILLA CUSTARD DESSERTS

JOURNAL OF SENSORY STUDIES, Issue 3 2007
JON F. PRINZ
ABSTRACT A trained panel of 19 subjects were asked to rate a number of sensory attributes of commercially available vanilla custard desserts. Stimuli were placed in plastic cups and were sampled using 11-mm-diameter straws. In total, 304 samples were weighed before and after sampling and the volume ingested was calculated. The subjects were categorized into two groups on the basis of the mean volume ingested per sample (< and >10.6 mL). There were significant differences in the ratings between the two groups for temperature, creamy, astringent, melting and airy mouthfeels and rough and fatty after-feel. We suggest that in sensory testing, it is important to either control or measure bite size to reduce intersubject variability. Manufacturers and caterers may also be able to modify the perception of their products by providing cues to the appropriate bite size by controlling the size of the spoon or container provided. [source]


DUSKY DOLPHIN (LAGENORHYNCHUS OBSCURUS) FORAGING IN TWO DIFFERENT HABITATS: ACTIVE ACOUSTIC DETECTION OF DOLPHINS AND THEIR PREY

MARINE MAMMAL SCIENCE, Issue 2 2004
Kelly J. Benoit-Bird
Abstract Active-acoustic surveys were used to determine the distribution of dusky dolphins and potential prey in two different New Zealand locations. During seven survey days off Kaikoura Canyon, dusky dolphins were found within the DeepScattering Layer (DSL) at 2000 when it rose to within 125 m of the surface. As the DSL rose to 30 m at 0100, the observed depth of dolphins decreased, presumably as the dolphins followed the vertical migration of their prey. Acoustically identified subgroups of coordinated animals ranged from one to five dolphins. Time, depth of layer, and layer variance contributed significantly to predicting foraging dusky dolphin subgroup size. In the much shallower and more enclosed Admiralty Bay, dolphins noted at the surface as foraging were always detected with the sonar, but were never observed in coordinated subgroups during the brief (two-day) study there. In Admiralty Bay dolphin abundance was correlated with mean volume scattering from potential prey in the water column; and when volume scattering, an index of prey density, was low, dolphins were rarely present. Ecological differences between the deep waters of Kaikoura Canyon and the shallow nearshore waters of Admiralty Bay may result in differences in how, when, and in what social groupings dusky dolphins forage. [source]


Face resurfacing using a cervicothoracic skin flap prefabricated by lateral thigh fascial flap and tissue expander

MICROSURGERY, Issue 7 2009
Ph.D., Qingfeng Li M.D.
Background: Resurfacing of facial massive soft tissue defect is a formidable challenge because of the unique character of the region and the limitation of well-matched donor site. In this report, we introduce a technique for using the prefabricated cervicothoracic skin flap for facial resurfacing, in an attempt to meet the principle of flap selection in face reconstructive surgery for matching the color and texture, large dimension, and thinner thickness (MLT) of the recipient. Materials: Eleven patients with massive facial scars underwent resurfacing procedures with prefabricated cervicothoracic flaps. The vasculature of the lateral thigh fascial flap, including the descending branch of the lateral femoral circumflex vessels and the surrounding muscle fascia, was used as the vascular carrier, and the pedicles of the fascial flap were anastomosed to either the superior thyroid or facial vessels in flap prefabrication. A tissue expander was placed beneath the fascial flap to enlarge the size and reduce the thickness of the flap. Results: The average size of the harvested fascia flap was 6.5 × 11.7 cm. After a mean interval of 21.5 weeks, the expanders were filled to a mean volume of 1,685 ml. The sizes of the prefabricated skin flaps ranged from 12 × 15 cm to 15 × 32 cm. The prefabricated skin flaps were then transferred to the recipient site as pedicled flaps for facial resurfacing. All facial soft tissue defects were successfully covered by the flaps. The donor sites were primarily closed and healed without complications. Although varied degrees of venous congestion were developed after flap transfers, the marginal necrosis only occurred in two cases. The results in follow-up showed most resurfaced faces restored natural contour and regained emotional expression. Conclusion: MLT is the principle for flap selection in resurfacing of the massive facial soft tissue defect. Our experience in this series of patients demonstrated that the prefabricated cervicothoracic skin flap could be a reliable alternative tool for resurfacing of massive facial soft tissue defects. © 2009 Wiley-Liss, Inc. Microsurgery, 2009. [source]


Therapeutic efficacy of 5-fluorouracil-loaded microspheres on rat glioma: a magnetic resonance imaging study

NMR IN BIOMEDICINE, Issue 6 2001
L. Lemaire
Abstract The aim of this work was to assess the therapeutic efficacy of an intratumoral bolus injection of 5-fluorouracil (FU) compared to that of drug loaded in biodegradable microspheres, for the treatment of brain tumour. Experiments were carried out using a fast-growing C6-glioma rat model. The therapeutic protocols were performed 12 days after the injection of glioma cells. At this stage, the tumours were installed and the mean volume was 13,±,2,µl as measured by proton magnetic resonance (MR) imaging. This technique was used for the follow-up of the tumour volume with respect to time and therapy. In terms of rat survival, both therapies induced a significant 50% increase in animal life span (p,<,0.05) compared to animals receiving no drug or unloaded microspheres. Whilst no cure was observed, analysis of the MR images showed that the local and sustained delivery of FU slowed the tumour development in the vicinity of the microspheres by a factor of 3, compared with the bolus intratumoral injection. Copyright © 2001 John Wiley & Sons, Ltd. [source]


Stereological study of postnatal development in the mouse utricular macula

THE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 2 2005
Mette Kirkegaard
Abstract This study describes the morphometric changes taking place in the utricular macula of mice with ages in geometric progression from 1 to 512 days after birth. By using design-based stereological methods, the total volume and surface area of the sensory epithelium as well the total number of the hair cells and supporting cells were estimated. Finally, the numerical density, volume density, and mean volume of the individual cell types were determined. The major changes were found in the number of the individual cell types during the first couple of weeks, and a mature composition of cell types was not attained until 16 days after birth. There was no change in the total number of cells and no decline in the number of hair cells within the time period studied. J. Comp. Neurol. 492:132,144, 2005. © 2005 Wiley-Liss, Inc. [source]