Structure and Endogenous Oxygen Uptake of Embryonic Cells

One of the classic limitations of light microscopy has been the fact that three dimensional biological events could only be visualized in two dimensions. Recently, this shortcoming has been overcome by combining the technologies of laser scanning confocal microscopy (LSCM) and computer processing of microscopical data by volume rendering methods. We have employed these techniques to examine morphogenetic events characterizing early development of sea urchin embryos. Specifically, the fourth cleavage division was examined because it is at this point that the first morphological signs of cell differentiation appear, manifested in the production of macromeres and micromeres by unequally dividing vegetal blastomeres.The mitotic spindle within vegetal blastomeres undergoing unequal cleavage are highly polarized and develop specialized, flattened asters toward the micromere pole. In order to reconstruct the three-dimensional features of these spindles, both isolated spindles and intact, extracted embryos were fluorescently labeled with antibodies directed against either centrosomes or tubulin.

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The biochemistry of drugs and doping methods used to enhance aerobic sport performance

Essays in Biochemistry ◽

10.1042/bse0440063 ◽

2008 ◽

Vol 44 ◽

pp. 63-84 ◽

Cited By ~ 7

Author(s):

Chris E. Cooper

Keyword(s):

Oxygen Uptake ◽

Oxygen Content ◽

Oxygen Delivery ◽

Sport Performance ◽

Blood Substitutes ◽

Altitude Training ◽

Blood Oxygen ◽

Oxygen Carriers ◽

Sports Performance ◽

Blood Doping

Optimum performance in aerobic sports performance requires an efficient delivery to, and consumption of, oxygen by the exercising muscle. It is probable that maximal oxygen uptake in the athlete is multifactorial, being shared between cardiac output, blood oxygen content, muscle blood flow, oxygen diffusion from the blood to the cell and mitochondrial content. Of these, raising the blood oxygen content by raising the haematocrit is the simplest acute method to increase oxygen delivery and improve sport performance. Legal means of raising haematocrit include altitude training and hypoxic tents. Illegal means include blood doping and the administration of EPO (erythropoietin). The ability to make EPO by genetic means has resulted in an increase in its availability and use, although it is probable that recent testing methods may have had some impact. Less widely used illegal methods include the use of artificial blood oxygen carriers (the so-called ‘blood substitutes’). In principle these molecules could enhance aerobic sports performance; however, they would be readily detectable in urine and blood tests. An alternative to increasing the blood oxygen content is to increase the amount of oxygen that haemoglobin can deliver. It is possible to do this by using compounds that right-shift the haemoglobin dissociation curve (e.g. RSR13). There is a compromise between improving oxygen delivery at the muscle and losing oxygen uptake at the lung and it is unclear whether these reagents would enhance the performance of elite athletes. However, given the proven success of blood doping and EPO, attempts to manipulate these pathways are likely to lead to an ongoing battle between the athlete and the drug testers.

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Can normalization for peak oxygen uptake of ventilatory response increase prognostic power of cardiopulmonary exercise test in patients with chronic heart failure?

European Journal of Heart Failure Supplements ◽

10.1016/s1567-4215(08)60201-5 ◽

2008 ◽

Vol 7 ◽

pp. 73-74

Author(s):

A TOSTE ◽

R SOARES ◽

J FELICIANO ◽

R RAMOS ◽

S SILVA ◽

...

Keyword(s):

Heart Failure ◽

Chronic Heart Failure ◽

Oxygen Uptake ◽

Exercise Test ◽

Ventilatory Response ◽

Peak Oxygen Uptake ◽

Cardiopulmonary Exercise Test ◽

Cardiopulmonary Exercise ◽

Response Increase ◽

Prognostic Power

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Sodium bicarbonate ingestion does not alter the slow component of oxygen uptake kinetics in professional cyclists

Journal of Sports Sciences ◽

10.1080/0264041031000070949 ◽

2003 ◽

Vol 21 (1) ◽

pp. 39-47 ◽

Cited By ~ 17

Author(s):

ALFREDO SANTALLA ◽

MARGARITA PÉREZ ◽

MANUEL MONTILLA ◽

LÁZARO VICENTE ◽

RICHARD DAVISON ◽

...

Keyword(s):

Oxygen Uptake ◽

Sodium Bicarbonate ◽

Slow Component ◽

Oxygen Uptake Kinetics ◽

Uptake Kinetics

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Ventilatory threshold is related to walking tolerance in patients with intermittent claudication

VASA ◽

10.1024/0301-1526/a000203 ◽

2012 ◽

Vol 41 (4) ◽

pp. 275-281 ◽

Cited By ~ 3

Author(s):

da Rocha Chehuen ◽

G. Cucato ◽

P. dos Anjos Souza Barbosa ◽

A. R. Costa ◽

M. Ritti-Dias ◽

...

Keyword(s):

Blood Flow ◽

Oxygen Uptake ◽

Intermittent Claudication ◽

Lower Limb ◽

Ventilatory Threshold ◽

Reactive Hyperemia ◽

Ankle Brachial Index ◽

Metabolic Parameters ◽

Walking Distance ◽

The Relationship

Background: This study assessed the relationship between lower limb hemodynamics and metabolic parameters with walking tolerance in patients with intermittent claudication (IC). Patients and methods: Resting ankle-brachial index (ABI), baseline blood flow (BF), BF response to reactive hyperemia (BFRH), oxygen uptake (VO2), initial claudication distance (ICD) and total walking distance (TWD) were measured in 28 IC patients. Pearson and Spearman correlations were calculated. Results: ABI, baseline BF and BF response to RH did not correlate with ICD or TWD. VO2 at first ventilatory threshold and VO2peak were significantly and positively correlated with ICD (r = 0.41 and 0.54, respectively) and TWD (r = 0.65 and 0.71, respectively). Conclusions: VO2peak and VO2 at first ventilatory threshold, but not ABI, baseline BF and BFHR were associated with walking tolerance in IC patients. These results suggest that VO2 at first ventilatory threshold may be useful to evaluate walking tolerance and improvements in IC patients.

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