Decrease In Blood pH Research Articles

Impact of blood storage duration on hematologic, blood gas, biochemical, and oxidative stress variables in sheep undergoing allogeneic blood transfusions.

Hemotherapy in ruminants is limited to whole blood transfusions, sometimes with stored blood for up to 42days, but little attention has been given to the effect of blood storage times and recipient responses after transfusions. We aimed to evaluate the hematologic and serum biochemical effects after allogeneic blood transfusion with either fresh or stored blood in sheep. We also sought to examine hematologic and biochemical analyte changes in the store blood. Eighteen sheep underwent a single phlebotomy to remove 40% of their blood volume. The sheep were divided into three experimental groups, G0, G15, and G35, which included six animals, each receiving 20mL/kg of either fresh blood or blood stored in citrate, phosphate, dextrose, and adenine (CPDA-1) bags for 15 and 35days, respectively. Biochemical, hematologic, coagulation, blood gas, lipid peroxidation, and oxidative stress test evaluations were performed using the blood samples gathered at T0 (before transfusion), 30minutes (T30m), 6, 12, 24, 48, 72, and 96hours (T6h-T96h), 8days (T8d), and 16days (T16d) after transfusions. Sheep exhibited increases in packed cell volumes, red blood cell counts, and total hemoglobin concentrations at T30m (P<.05). G35 animals had greater plasma hemoglobin concentrations at T12h and decreased blood pH values at T6h, characterized by slight metabolic acidemia. Regarding oxidative stress, G35 animals had decreased catalase activities from T0 at T30m, T6h, T12h, and T24h, indicating that hemolysis had occurred, which was supported by concomitant increases in bilirubin. Sheep transfused with 35-day stored blood exhibited greater hematologic, blood gas, biochemical, and oxidative alterations; however, anemic animals without comorbidities effectively reversed those alterations.

Physiological and Hereditary Hyperbilirubinemia in Athletes: Role in Reducing Efficiency and Correction Methodology

Under high-intensity loads, the athlete's bodies take place a number of biochemical reactions and physiological processes that can lead to hyperbilirubinemia. The factors that can initiate the onset of this phenomenon include the syndrome of micro-damage muscle, violation of the integrity of erythrocyte membranes, decreased blood pH, malnutrition and increase oxygen demand of the body. Degree of expression of manifestations of physiological bilirubinemia depends on the level of adaptation of the athlete to the physical activities offered. Hyperbilirubinemia in athletes can be one of the components of the deterioration of the functional state, forming the symptoms of endogenous intoxication. The relevance of this problem in sport lies in the relatively low detection rate of hyperbilirubinemia due to the lack of regular screening studies. However, in drawing up a plan of nutritional- metabolic support for training and competitive activity and recovery measures, must not only the individual reaction of the athlete body to physical activity, but also the severity of shifts in the indicators of bilirubin metabolism and their ratio. The article describes the reasons for the increase in bilirubin levels, which can be caused by both the effect of physical activity and by the presence of pathological processes in athletes. The factors influencing the blood serum’s bilirubin content are also highlighted, which include the state of erythrocyte cell membranes and the rate of hemoglobin destruction, the functional state of the liver, the specifics of physical loads and the use of ergogenic pharmacological agents by athletes. Particular accent has been placed on the illumination of hereditary hyperbilirubinemias, which may have been detected at the stage of selection of athletes. The most common phenomenon is Gilbert's syndrome, which occurs in 2-5% of cases in the general population, is characterized in the clinic by a benign flow and is manifested by episodes of jaundice and an increase in total bilirubin content to moderate values due to indirect. The frequency of detection of hyperbilirubinemias in the population of athletes is 4.68%, among which Gilbert's disease accounts for almost half (48.7%). Conclusion. The work highlighted the pathogenesis and diagnostic algorithm of Gilbert's disease, and also emphasized that its drug prevention and correction in athletes to maintain functional and physical fitness should be carried out taking into account anti-doping rules, which requires upon diagnosis timely receipt of a therapeutic exclusion

A marine teleost, Opsanus beta, compensates acidosis in hypersaline water by H+ excretion or reduced HCO3- excretion rather than HCO3- uptake.

Increases in ambient salinity demand parallel increases in intestinal base secretion for maintenance of osmoregulatory status, which is likely the cause of a transient acidosis following transfer of euryhaline fish from freshwater to seawater. It was predicted that transfer of the marine Gulf toadfish (Opsanus beta) from seawater (35 ppt) to hypersaline (60 ppt) seawater (HSW) would lead to a transient acidosis that would be compensated by increases in branchial acid excretion to offset the acid-base disturbance. Toadfish exposed to HSW showed a significant decrease in blood pH and [HCO3-] but no increase in pCO2, followed by a full recovery after 48-96h. A similar metabolic acidosis and recovery was found when fish were exposed to 60-ppt HCO3--free seawater (HEPES-buffered), which may suggest that compensation for intestinal base loss during hypersaline treatment is from gill H+ excretion rather than gill HCO3- uptake. However, we cannot rule out that reduced branchial HCO3- excretion contributed to an increase in net acid excretion. Since colchicine prevents full compensation, translocation of H+ and/or HCO3- transporters between cytosolic compartments and plasma membrane fractions might be involved in compensating for the hypersalinity-induced acidosis. Translocation of transporters rather than de novo synthesis may represent a faster and less energetically demanding response to rapidly fluctuating and high salinities encountered by toadfish in their natural environment.

The treating dogs for enteropathy with PLE

One of the most common and poorly understood diseases in dogs and cats is enteropathy with PLE. The disease occurs, according to studies, in dogs of 2-6 years old breeds: Yorkshire terrier, German shepherd, and Golden Retriever. The disease in most cases is manifested by anorexia, polydipsia, diarrhea, fever up to 39.7 °C, tachycardia (145–170 bpm), and abdominal pain. In sick dogs, leucocytosis (21.0 ± 0.50 g/l), thrombocytosis (480.0 ± 10.13 g/l), oligocythaemia (4.8 ± 0.12 T/l), oligochromemia (109.0 ± 5.06 g/l), decrease in haematocrit value (29.0 ± 1.21 % in healthy people 42.3 ± 0.65 %). In a biochemical study of blood in dogs with enteropathy with PLE, hypoproteinaemia (38.2 ± 0.65 g/l), hypoalbuminemia (9.6 ± 0.61 g/l); hyperazotemia (8.6 ± 0.37 mmol/l), hypercholesterolemia (8.0 ± 0.23 mmol/l), hyperenzymemia of LF (ALP) and ALT (alanine aminotransferase), hyponatremia, hypokalaemia, hypochloraemia, decreased blood pH values (7.26 ± 0.013), HCO3- (15.3 ± 0.71 mmol/L) and AG (2.85 ± 0.084 mmol/L, in healthy people 14.3 ± 1.17 mmol/L). The diagnosis of enteropathy with PLE was confirmed by studies in feces of α1-antitrypsin, which in sick dogs with PLE was more than 22 mg/dL (in clinically healthy dogs up to 18 mg/dL). A treatment regimen with trometamol, Xylat, Disparkol, Voluven, Reopoliglukin, Maropitant, prednisolone, α-lysine escinat, albumin, Presorb and feed additives Vivonex Ten Elemental and Royal Canin Recoveri promotes the recovery of dogs, prevents their death. Under the action of drugs, erythro- and leuсocytopoiesis, protein-synthesizing (the content of total protein and albumin increased by 34.3 and 246.9 %, respectively) and urea-forming functions of hepatocytes improves. We have developed and tested a treatment scheme that restores the acid-base balance of the body, as indicated by the physiological values of blood pH, bicarbonates, anion gap (AG), Na+, K+, Cl- and Mg+.

Impaired Neonatal Immunity and Infection Resistance Following Fetal Growth Restriction in Preterm Pigs

Background: Infants born preterm or small for gestational age (SGA, due to fetal growth restriction) both show an increased risk of neonatal infection. However, it remains unclear how the co-occurrence of preterm birth and SGA may affect neonatal immunity and infection risk. We hypothesized that fetal growth restricted (FGR) preterm newborns possess impaired immune competence and increased susceptibility to systemic infection and sepsis, relative to corresponding normal birth weight (NBW) newborns.Methods: Using preterm pigs as a model for preterm infants, gene expression in lipopolysaccharide (LPS) stimulated cord blood was compared between NBW and FGR (lowest 25% birth weight percentile) preterm pigs. Next, clinical responses to a systemic Staphylococcus epidermidis (SE) challenge were investigated in newborn FGR and NBW preterm pigs. Finally, occurrence of spontaneous infections were investigated in 9 d-old FGR and NBW preterm pigs, with or without neonatal antibiotics treatment.Results: At birth, preterm FGR piglets showed diminished ex vivo cord blood responses to LPS for genes related to both innate and adaptive immunity, and also more severe septic responses following SE infection (e.g., higher blood lactate, decreased blood pH, neutrophil and platelet counts, relative to NBW pigs). After 9 d, FGR pigs had higher incidence and severity of spontaneous infections (e.g., higher bacterial densities in the bone marrow), increased regulatory T cell numbers, reduced neutrophil phagocytosis capacity, and impaired ex vivo blood gene responses to LPS, especially when receiving neonatal antibiotics.Conclusion: FGR at preterm birth is associated with poor immune competence, impaired infection resistance, and greater sepsis susceptibility in the immediate postnatal period. Our results may explain the increased morbidity and mortality of SGA preterm infants and highlight the need for clinical vigilance for this highly sensitive subgroup of preterm neonates.

Bicarbonate Unlocks the Ergogenic Action of Ketone Monoester Intake in Endurance Exercise.

ABSTRACTPurposeWe recently reported that oral ketone ester (KE) intake before and during the initial 30 min of a 3 h 15 min simulated cycling race (RACE) transiently decreased blood pH and bicarbonate without affecting maximal performance in the final quarter of the event. We hypothesized that acid–base disturbances due to KE overrules the ergogenic potential of exogenous ketosis in endurance exercise.MethodsNine well-trained male cyclists participated in a similar RACE consisting of 3 h submaximal intermittent cycling (IMT180′) followed by a 15-min time trial (TT15′) preceding an all-out sprint at 175% of lactate threshold (SPRINT). In a randomized crossover design, participants received (i) 65 g KE, (ii) 300 mg·kg−1 body weight NaHCO3 (BIC), (iii) KE + BIC, or (iv) a control drink (CON), together with consistent 60 g·h−1 carbohydrate intake.ResultsKE ingestion transiently elevated blood D-ß-hydroxybutyrate to ~2–3 mM during the initial 2 h of RACE (P < 0.001 vs CON). In KE, blood pH concomitantly dropped from 7.43 to 7.36 whereas bicarbonate decreased from 25.5 to 20.5 mM (both P < 0.001 vs CON). Additional BIC resulted in 0.5 to 0.8 mM higher blood D-ß-hydroxybutyrate during the first half of IMT180′ (P < 0.05 vs KE) and increased blood bicarbonate to 31.1 ± 1.8 mM and blood pH to 7.51 ± 0.03 by the end of IMT180′ (P < 0.001 vs KE). Mean power output during TT15′ was similar between KE, BIC, and CON at ~255 W but was 5% higher in KE + BIC (P = 0.02 vs CON). Time to exhaustion in the sprint was similar between all conditions at ~60 s (P = 0.88). Gastrointestinal symptoms were similar between groups.DiscussionThe coingestion of oral bicarbonate and KE enhances high-intensity performance at the end of an endurance exercise event without causing gastrointestinal distress.

Predictors of Delayed Neurological Sequelae after Acute Carbon Monoxide Poisoning at Zagazig University Hospitals

Background: Carbon monoxide (CO) is an odorless, tasteless and colorless gas that causes a potentially fatal illness with a tremendous burden due to significant mortality and morbidity. Carbon monoxide poisoning leads to the development of delayed neurological sequelae (DNS). Aim: To assess the possible risk factors that can predict the development of DNS after acute CO poisoning. Subjects and methods: The patients were recruited between January 2018 and December 2018. The study included 37 cases with acute CO poisoning. The medical history was taken thoroughly. Patients underwent general and neurological clinical assessments with laboratory investigations, including arterial blood gases (ABG), carboxyhemoglobin (COHb), cardiac enzymes, and serum lactate. At the time of admission, all patients were subjected to an electrocardiogram (ECG) and brain imaging (CT or MRI) of the brain. They were followed up three and six months after discharge for complete neurological examination and cognitive functions assessment using the Mini-Mental State Examination (MMSE). Results: Two patients died, both presenting with coma and hemodynamic instability. Five cases were excluded due to a lack of comprehension and refusal to follow-up. Out of the 30 patients who completed the follow-up, 67% survived with no complication, while DNS developed in 33% of the patients. Several predictors for development of DNS were identified. They included lower Glasgow coma score, duration of CO exposure, high COHb level, decrease in blood pH, elevated serum levels of creatine kinase and lactate, and abnormalities in brain structure. The time of DNS development extended to six months post-exposure. Conclusion: We conclude that several clinical and laboratory parameters can predict DNS. Recommendations: proper and accurate clinical and laboratory evaluation of any suspected case of acute CO poisoning should be performed especially those parameters proved to be predictors for DNS. The follow-up of cases should continue at least for six months post-exposure.

The effect of adding lactic acid to canine whole blood on platelet aggregation as measured by impedance aggregometry.

Acidemia in sick dogs often results from the accumulation of lactic acid. The resulting decrease in blood pH can have many physiologic effects, including alteration of platelet function. We aimed to evaluate the effect of hyperlactatemia and subsequent acidemia on platelet aggregation in canine blood using impedance aggregometry. Platelet aggregation was measured in blood from 27 healthy dogs using the Multiplate analyzer at baseline and after in vitro addition of two different volumes of lactic acid to adjust the pH. The area under the curve (AUC), reported by the Multiplate analyzer, was used to assess the extent of platelet aggregation in each sample. A linear mixed effects model was used to test for the association between platelet aggregation and pH. The association of baseline platelet aggregation with HCTs, platelet counts, and WBC counts was assessed using Pearson's correlations. Acidemia was associated with a significant decrease in platelet aggregation. No significant correlations were detected between platelet aggregation and HCT, platelet count, or WBC count. Platelet aggregation measured using the Multiplate analyzer showed substantial individual variation. Worsening acidemia due to the addition of lactic acid caused a mild but significant decrease in platelet aggregation in canine blood. The clinical significance of this change is uncertain but could be important when combined with other abnormalities of hemostasis associated with illness.

Destroyed thyroid by acidic blood during subarachnoid hemorrhage: Experimental study

Aim: Metabolic acidosis can negatively affect thyroid functions. The aim of this study is to show the damage in the thyroid gland caused by acidosis following subarachnoid hemorrhage (SAH). Methods: Twenty rabbits were chosen from our recent SAH studies. Five healthy rabbits were included in the control group, five were included in the SHAM group, which received 1 ml of saline, and ten rabbits, chosen from SAH-induced animals with decreased blood pH, constituted the study group. TSH, T3, T4 and blood pH values were recorded before, during and after the experimental procedures. Densities of the normal and degenerated epithelial cell of thyroid glands were estimated using stereological methods. The relationship between blood pH and thyroid hormone values, and degenerated epithelial cell densities were analyzed statistically.Results: pH values of blood were measured as 7.35 (0.037), 7.32 (0.05), and 7.21 (0.012) in the control, SHAM and SAH groups, respectively. The estimation of normal and degenerated epithelial cells per square milimeter of follicles was calculated as wall surface/cell surface. The mean normal epithelial cell count was 5,000 (750) in normal thyroid follicles. Mean degenerated epithelial cells counts were 50 (9) in the normal group, 154 (30) in the SHAM group and 460 (80) in the study group. For all results there was statistically significant difference between the control, SHAM and SAH groups (P&lt;0.001).Conclusions: Acidosis, one of the most fatal complications of SAH, may damage the thyroid gland with neurovascular network degeneration.

Prevalence of latent acidotic stress in dairy cows in the Şanliurfa region

This study aimed to determine the incidence of latent acidotic stress (LAS), which is an important problem in dairy cow breeding in Turkey, to investigate net acid-base excretion in urine, and to provide veterinary doctors with information about the early diagnosis and treatment of LAS. Two study groups were formed according to the rumen fluid pH values: LAS group (19 cows) with 5.2 &lt; pH &lt; 6.0 (19 cows) and healthy group (81 cows) with 6.0 &lt; pH &lt; 7.2. Blood, urine and ruminal fluid samples were taken after a general clinical examination of the animals. The physical properties of the rumen fluid, methylene blue reduction time, total infusoria number, and volatile fatty acid (VFA) amounts were determined. In addition, examinations of blood gases, urine pH, and net acid-base excretion (NABE) were performed. The general physical examination did not reaveal any statistically significant difference in the body temperature between the LAS group (n = 19) and the control group (n = 81) (p = 0.614), but a significant increase in the heartbeat, respiratory frequency, and the number of rumen movements was observed in the LAS group (p = 0.001). The following findings were observed in the rumen fluid from cows of the LAS group: decreased methylene blue reduction time (p = 0.001), decreased pH (p = 0.001) and infusoria density (p = 0.001), increased sedimentation time (p = 0.001) and total VFA amount (p = 0.001), no flotation. Compared with the healthy cows, the LAS group showed decreased blood pH (p = 0.001) and oxygen pressure (pO2) (p = 0.001), increased carbon dioxide pressure (pCO2), base excess (BE) and bicarbonate (HCO3) values (p = 0.001), and decreased urine pH (p = 0.001) and net acid-base excretion (p = 0.001) values. The incidence of latent acidotic stress in dairy cows in the Sanliurfa region was determined as 19%. In addition, it was concluded that net acid-base excretion values in urine can be used as an auxiliary parameter in the diagnosis of LAS and can be easily applied in the field.

Determination of renal blood flow with Doppler ultrasound and the hypertension prevalence and acid-base level in dogs with chronic renal failure

Chronic renal failure (CRF) is an important cause of morbidity and mortality in dogs. The aim of this study is to investigate the renal Doppler measurements, blood hypertension and acid-base levels in dogs with chronic renal failure. Twenty-six dogs previously diagnosed with chronic renal failure were compared with twenty healthy dogs. A complete blood cell, biochemical profile, urinalysis, blood gasses, blood pressure were analyzed and changes in renal blood flow were measured by renal Doppler ultrasonography. The dogs with CRF had significantly higher serum blood urea nitrogen, creatinine and phosphorus concentration, significantly lower packed cell volume, and urine specific gravity than control dogs. Positive correlation was determined between serum creatinine levels and renal Doppler indices. There were significant decreases in blood pH and bicarbonate. Indirect blood pressure measurements were slightly increased in CRF dogs. Renal Doppler measurement was observed as a helpful tool in diagnosing the CRF in dogs. Identification of acidosis and hypertension may help in developing treatments that slow the rate of progression of chronic renal failure.

Effects of light-sources and photoperiod on hemato-physiological indices of broilers grown to heavy weights

We evaluated the influence of light sources and photoperiod on blood physiological variables in four trials. In each trial, 720 1-d-old Ross × Ross 708 chicks were randomly distributed into 12 environmentally controlled rooms (30 males/30 females/room). The experimental design was a 4 × 3 factorial treatments consisting of four light sources [incandescent (ICD, standard), compact fluorescent, neutral light emitting diode, and cool poultry-specific-filtered LED] and three photoperiods [long/continuous (23L:1D), regular/intermittent (2L:2D), and short/non-intermittent (8L:16D)] from d8-d56 at 50% relative humidity. Birds were fed the same diet, while feed and water were provided ad libitum. Blood samples were collected from the brachial wing vein on d 14, 28, 42, and 56 of age and analyzed immediately. Light sources had significant (P ≤ 0.05) effects on body weight (BW), and some of the selected blood physiological indices except Hb, Hct, Ca2+ angap, glucose, and corticosterone. Also, the photoperiods had significant (P ≤ 0.05) effects on BW and most of the selected blood physiological indices except HCO3-, angap, glucose, corticosterone, and T4. However, all these changes were still within the normal acid-base homeostasis and physiological ranges of this species. Acid-base regulation during the short photoperiod exposure had not deteriorated despite higher pCO2 that consequently decreased blood pH, due to a respiratory acidosis. Plasma corticosterone and glucose concentrations were not affected by treatments, suggesting an absence of physiological stress. It was concluded that the three LED light bulbs evaluated could be suitable for replacement of ICD along with the regular/intermittent photoperiod. Commercial poultry facilities can thereby reduce energy costs and optimize production efficiency without compromising the welfare of broilers grown to heavy weights (>3kg).

The effects of endurance exercise in hypoxia on acid-base balance and potassium kinetics: a randomized crossover design in male endurance athletes

BackgroundExercise-induced disturbance of acid-base balance and accumulation of extracellular potassium (K+) are suggested to elicit fatigue. Exercise under hypoxic conditions may augment exercise-induced alterations of these two factors compared with exercise under normoxia. In the present study, we investigated acid-base balance and potassium kinetics in response to exercise under moderate hypoxic conditions in endurance athletes.MethodsNine trained middle-to-long distance athletes [maximal oxygen uptake (VO2max) 57.2 ± 1.0 mL/kg/min] completed two different trials on different days, consisting of exercise in moderate hypoxia [fraction of inspired oxygen (FiO2) = 14.5%, H trial] and exercise in normoxia (FiO2 = 20.9%, N trial). They performed interval endurance exercise (8 × 4 min pedaling at 80% of VO2max alternated with 2-min intervals of active rest at 40% of VO2max) under hypoxic or normoxic conditions. Venous blood samples were obtained to determine blood lactate, pH, bicarbonate ion, and K+ concentrations before exercise, during exercise, and after exercise.ResultsThe blood lactate concentrations increased significantly with exercise in both trials. Exercise-induced blood lactate elevations were significantly greater in the N trial than in the H trial at all time points (P = 0.012). Bicarbonate ion concentrations (P = 0.001) and blood pH (P = 0.019) during exercise and post-exercise periods were significantly lower in the N trial than in the H trial. A significantly greater exercise-induced elevation in blood K+ concentration was produced in the N trial than in the H trial during exercise and immediately after exercise (P = 0.03).ConclusionsHigh-intensity interval exercise on a cycle ergometer under moderate hypoxic conditions did not elicit a decrease in blood pH or elevation in K+ levels compared with an equivalent level of exercise under normoxic conditions.

Main effects of light sources, photoperiods, and genetic strains on blood physiological variables of broilers grown to heavy weights.

Effects of light sources, photoperiods, and genetic strains on blood physiological variables of broilers grown to heavy weights were investigated in 2 trials. The experimental design was a 4 × 2 × 2 factorial consisting of 4 light sources [incandescent (ICD, standard), compact fluorescent (CFL), neutral light emitting diode (Neutral‐LED), and cool poultry specific filtered LED (Cool‐PSF‐LED)], 2 photoperiods (Regular/intermittent [2L:2D], and Short [8L:16D], and 2 genetic strains (Ross × Ross 708, Cobb 700). In each trial, 480 (240 males/240 females) 1‐d‐old chicks of each strain from different commercial hatcheries were equally and randomly distributed into 16 environmental control rooms (30 males + 30 females/room) at 50% RH. Each room was randomly assigned one of 16 treatments from d 1 to 56 d of age. Birds were provided similar diets. Feed and water were provided ad libitum. Venous blood samples were collected on d 14, 28, 42, and d 56 of age and analyzed immediately. Cool‐PSF‐LED light sources had significant (P ≤ 0.05) effects on BW, Hb, Hct, electrolytes, angap, and mOsm in comparison with birds reared under ICD, but all these changes were still within the normal acid‐base homeostasis and physiological ranges. Also, the short photoperiod significantly (P ≤ 0.05) reduced BW, pH level, pO2, sO2, and Ca2+, with significantly (P ≤ 0.05) elevated pCO2, Hct, Hb, and McHc concentrations. Acid‐base regulation during short photoperiod exposure had not deteriorated despite higher pCO2 that consequently decreased blood pH due to a respiratory acidosis. In addition, Cobb 700 had significantly (P ≤ 0.05) increased BW, pCO2, Hct, Hb, Ca2+, Cl−, McHc, and angap along with significantly (P ≤ 0.05) reduced pH level, pO2, HCO3−, and glucose in comparison with Ross × Ross 708. Plasma corticosterone was not affected by light sources, photoperiod, genetic strain or their interaction, indicating that exposure of broiler chickens to the short photoperiod markedly affects some physiological blood variables without inducing stress in modern broilers grown to heavy weights. It was concluded that the 3 LED light bulbs evaluated may be suitable for replacement of ICD along with the regular/intermittent photoperiod for commercial poultry facilities to reduce energy costs and optimize production efficiency without compromising the welfare of broilers grown to heavy weights.Support or Funding InformationNoneThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

On the Metabolism of Exogenous Ketones in Humans.

Background and aims: Currently there is considerable interest in ketone metabolism owing to recently reported benefits of ketosis for human health. Traditionally, ketosis has been achieved by following a high-fat, low-carbohydrate “ketogenic” diet, but adherence to such diets can be difficult. An alternative way to increase blood D-β-hydroxybutyrate (D-βHB) concentrations is ketone drinks, but the metabolic effects of exogenous ketones are relatively unknown. Here, healthy human volunteers took part in three randomized metabolic studies of drinks containing a ketone ester (KE); (R)-3-hydroxybutyl (R)-3-hydroxybutyrate, or ketone salts (KS); sodium plus potassium βHB.Methods and Results: In the first study, 15 participants consumed KE or KS drinks that delivered ~12 or ~24 g of βHB. Both drinks elevated blood D-βHB concentrations (D-βHB Cmax: KE 2.8 mM, KS 1.0 mM, P < 0.001), which returned to baseline within 3–4 h. KS drinks were found to contain 50% of the L-βHB isoform, which remained elevated in blood for over 8 h, but was not detectable after 24 h. Urinary excretion of both D-βHB and L-βHB was <1.5% of the total βHB ingested and was in proportion to the blood AUC. D-βHB, but not L-βHB, was slowly converted to breath acetone. The KE drink decreased blood pH by 0.10 and the KS drink increased urinary pH from 5.7 to 8.5. In the second study, the effect of a meal before a KE drink on blood D-βHB concentrations was determined in 16 participants. Food lowered blood D-βHB Cmax by 33% (Fed 2.2 mM, Fasted 3.3 mM, P < 0.001), but did not alter acetoacetate or breath acetone concentrations. All ketone drinks lowered blood glucose, free fatty acid and triglyceride concentrations, and had similar effects on blood electrolytes, which remained normal. In the final study, participants were given KE over 9 h as three drinks (n = 12) or a continuous nasogastric infusion (n = 4) to maintain blood D-βHB concentrations greater than 1 mM. Both drinks and infusions gave identical D-βHB AUC of 1.3–1.4 moles.min.Conclusion: We conclude that exogenous ketone drinks are a practical, efficacious way to achieve ketosis.

Numerical Modeling of Fish Mortality at High CO2 Concentrations Representing Acclimation

A mortality model was developed to predict the impact of high CO2 concentrations on marine fish. To allow for acclimation to a gradual increase of PCO2, the model includes acid–base regulation processes, such as respiration and ion-exchange at the gills. Because the physiological mechanism connecting a decrease in blood pH and mortality is not known, a statistical model was adopted. The mortality calculated for Japanese sillago experiencing a transient change of PCO2 compares moderately well with observations.

Diet-Induced Low-Grade Metabolic Acidosis and Clinical Outcomes: A Review.

Low-grade metabolic acidosis is a condition characterized by a slight decrease in blood pH, within the range considered normal, and feeding is one of the main factors that may influence the occurrence of such a condition. The excessive consumption of acid precursor foods (sources of phosphorus and proteins), to the detriment of those precursors of bases (sources of potassium, calcium, and magnesium), leads to acid-base balance volubility. If this condition occurs in a prolonged, chronic way, low-grade metabolic acidosis can become significant and predispose to metabolic imbalances such as kidney stone formation, increased bone resorption, reduced bone mineral density, and the loss of muscle mass, as well as the increased risk of chronic diseases such as type 2 diabetes mellitus, hypertension, and non-alcoholic hepatic steatosis. Considering the increase in the number of studies investigating the influence of diet-induced metabolic acidosis on clinical outcomes, this review gathers the available evidence evaluating the association of this disturbance and metabolic imbalances, as well as related mechanisms. It is necessary to look at the western dietary pattern of most countries and the increasing incidence of non-comunicable diseases for the balance between fruit and vegetable intake and the appropriate supply of protein, mainly from animal sources, so that it does not exceed the daily recommendations.

Effects of acute and chronic hypoxia on acid-base regulation, hematology, ion, and osmoregulation of juvenile American paddlefish.

Despite the increasing prevalence of hypoxia in natural habitats occupied by the American paddlefish, basal bony fish, and ram ventilator, information about its response to hypoxia is scarce. To understand the physiological and biochemical responses of juvenile paddlefish (~150g) to acute (<24h) and chronic hypoxia (≥24h), blood oxygen transport, blood acid-base balance, and metabolic stress were evaluated under four different partial pressures of oxygen [pO2; normoxia (148mmHg), mild hypoxia (89mmHg), moderate hypoxia (59mmHg), and extreme hypoxia (36mmHg)], all at 21 °C. Arterial blood samples were collected from paddlefish after they had been exposed to treatments for 0.25, 2, 6, 24, and 72h, and analyzed for hematocrit, pO2, total oxygen content, oxygen saturation, pCO2, pH, hemoglobin, Na+, K+, Ca2+, Cl-, glucose, and lactate. Mild hypoxia only caused a reduction in blood pO2 and oxygen saturation. Both acute and chronic moderate and extreme hypoxia caused a decrease in blood pH, pO2, total oxygen content, plasma Na+, and Cl- at all time points. Acute moderate and extreme hypoxia resulted in an increase in blood pCO2, plasma glucose, lactate, and hematocrit. Chronic exposure to moderate hypoxia resulted in an increase in plasma lactate, red blood cell count, and hemoglobin. This study shows that paddlefish are able to physiologically compensate for mild hypoxia, but exhibit secondary stress responses and are unable to return to homeostasis when exposed to both acute and chronic moderate hypoxia, and die after 3-8h of extreme hypoxia.

Effects of betaine on biological functions in meat-type ducks exposed to heat stress

Heat stress in hot seasons is a major problem in poultry production, particularly in humid areas. The aim of this study was to determine the pharmacodynamics of betaine on the blood and cecal short chain fatty acid profile in meat-type ducks exposed to heat stress. Three-hundred-sixty meat-type ducks (Anas platyrhynchos domesticus) were randomly allocated into 4 treatments: C (heat stress control without betaine), T1 (700 ppm betaine), T2 (1,000 ppm betaine), and T3 (1,300 ppm betaine). Each treatment had 6 replicated pens with 15 meat-type ducks per pen. The study was conducted for 42 days. Our findings revealed that the betaine group had higher body weight gain compared to the control group under heat stress (P < 0.05). Betaine supplementation resulted in more significant improvement in hematological indicators such as RBCs and platelet counts than the heat stress control group (P < 0.05). Under the heat-wave environment, supplementation of betaine manifested a significant decrease in blood pH (P < 0.05) but not in electrolytes (Na+, K+ and Cl−) and gas concentration. The concentration of short chain fatty acids (SCFA) in the cecum was higher than the control under heat stress conditions. The total SCFA, acetic acid, and propionic acid production was higher in the betaine supplemented groups compared to the heat stress control group (P < 0.05). Results showed that betaine supplementation has beneficial effects in meat-type ducks under heat stress on short chain fatty acid levels, blood biochemical parameters, and body weight.

Effects of enzymatically treated Artemisia annua L. on growth performance and some blood parameters of broilers exposed to heat stress.

To evaluate the effects of enzymatically treated Artemisia annua L. (EA) on growth performance and some blood parameters of broilers exposed to heat stress (HS), 320 22-day-old Arbor Acres male broilers were randomly allotted into five groups with eight replicates of eight birds each. Broilers in the control group were housed at 22±1°C and fed the basal diet. Broilers in the HS, HS-EA0.75 , HS-EA1.00 and HS-EA1.25 groups were reared under HS (34±1°C for 8h/day and 22±1°C for 16h/day), and fed basal diet with 0, 0.75, 1.00 and 1.25g/kg EA, respectively. The experiment ended at 42 days. Dietary 1.00 and 1.25g/kg EA decreased blood pH and elevated body weight gain, feed intake and carcass yield compared to the HS group. Broilers fed EA diets had lower serum concentrations of malondialdehyde and corticosterone and activities of alanine aminotransferase and aspartate aminotransferase, and higher serum total superoxide dismutase activity, tri-iodothyronine concentration and tri-iodothyronine/thyroxine than the HS group. Serum catalase activity in HS-EA1.00 and HS-EA1.25 groups and activity to inhibit hydroxyl in the HS-EA1.00 group were higher than the HS group. In conclusion, dietary 0.75-1.25g/kg EA addition alleviated HS induced impairments in broilers.