1.1 Os níveis séricos de cálcio (Ca), fósforo (P), fosfatase alcalina (FA), paratormônio-intacto (PTH), pH e bicarbonato sérico (HCO3) ou reserva alcalina (CO2 total) devem ser determinados em todas as crianças e adolescentes nos estágios II a V da doença renal crônica (DRC). A frequência dessas determinações deve ser baseada na presença e na magnitude das alterações e na velocidade de progress...

When Bufo marinus burrows, the skin becomes intimately surrounded by substrate but the nares always remain exposed to the surface air. Upon entering into a state of dormancy the animal hypoventilates and this together with the loss of the skin as a respiratory site results in a rise in arterial blood PCO2 despite a probable decline in metabolism. Even though lung ventilation falls, the toad reg...

The processes of CO2 acquisition were characterized for the acid-tolerant, free-living chlorophyte alga, CPCC 508. rDNA data indicate an affiliation to the genus Coccomyxa, but distinct from other known members of the genus. The alga grows over a wide range of pH from 3.0 to 9.0. External carbonic anhydrase (CA) was detected in cells grown above pH 5, with the activity increasing marginally fro...

OBJECTIVE To investigate respiratory and metabolic components of gestational age-dependent umbilical cord blood gas changes. STUDY DESIGN Cord blood gases were determined in 1336 vigorous singletons with uncomplicated cephalic vaginal delivery at 37-43 weeks. Linear regression analysis and non-parametric statistics were used with a P < 0.05 being significant. RESULTS Gestational age correla...

absorption in rabbit outer medullary collecting duct: role of luminal carbonic anhydrase. Am. J. Physiol. 274 (Renal Physiol. 43): F139–F147, 1998.—Membrane-bound luminal carbonic anhydrase (CA) IV, by catalyzing the dehydration of carbonic acid into CO2 plus water, facilitates H1 secretion in the renal outer medullary collecting duct from the inner stripe (OMCDi). To examine the role of CA IV ...

Reptiles habitually ingest large meals at infrequent intervals, leading to changes in acid-base status as the net secretion of acid to the stomach causes a metabolic alkalosis (the alkaline tide). In chronically cannulated and undisturbed amphibians and reptiles, the pH changes in arterial blood are, nevertheless, reduced by a concomitant respiratory acidosis (increased P(CO2) caused by a relat...

When mixed venous blood is oxygenated in alveolar air with higher PCO2, the PCO2 within the red cell is though to exceed the alveolar PCO2 due to the Haldane effect and to block the inward CO2 diffusion. If the direction of the CO2 diffusion is not reversed during the contact time, the HCO2-gain in the plasma will not exceed the amount estimated from venoalveolar PCO2 difference by using a CO2 ...

BACKGROUND: CO2-pneumoperitoneum used in endoscopic surgery induces system effects by CO2 absorption. This study investigated the effect of the addition of O2 to CO2-pneumoperitoneum, upon CO2 absorption. METHODS: The effect of a pneumoperitoneum using 100% CO2 or 94% CO2 6% O2 upon arterial blood gases, acid base and O2 homeostasis was evaluated. In series A suboptimal ventilation and a pneumo...

The gas carbon dioxide (CO2) plays a critical role in microbial and mammalian respiration, photosynthesis in algae and plants, chemoreception in insects, and even global warming . However, how CO2 is transported, sensed, and metabolized by microorganisms is largely not understood. For instance, CO2 is known to induce production of polysaccharide capsule virulence determinants in pathogenic bact...

The Lake Magadi tilapia, Oreochromis alcalicus grahami, thrives in highly alkaline geothermal springs and pools surrounding Lake Magadi, Kenya (control pH=9.9, CCO2=173 mmol l-1), has a functional hepatic ornithine&shy;urea cycle (OUC) and excretes all nitrogenous waste as urea-N at variable rates (JUrea) related to O2 consumption (M&middot;O2). The mean value of JUrea/M&middot;O2 (N/O2=0.183) ...