Serum L-lactate Research Articles

353 Zinc supplementation prior to transit and transit duration effects on feedlot performance and muscle fatigue of beef steers: Part I – Performance and Muscle Fatigue

Abstract This study investigated zinc (Zn) as a mitigation strategy for transit-induced muscle fatigue. Recently weaned Angus-cross steers (n = 80) were stratified by body weight (BW = 265 ± 18.0 kg) to a 2×2 factorial. Dietary (DIET) treatments of no supplemental Zn (Zn0) or 100 mg supplemental Zn/kg DM (Zn100; Zn as ZnSO4), were fed for 42 d before transit. Along with a transit duration (DUR) of 8 h (~707 km; 8H) or 18 h (~1,608 km; 18H) on d 0. Upon return, and for 56 d post-transit, all steers received Zn100. Individual feed disappearance was monitored using GrowSafe bunks (1 bunk/pen; 5 steers/pen). Body weights were collected on d -42, -41, -1, 0 (on truck), 1 (off truck), 2, 7, 28, 55, and 56. Blood samples for analysis of non-esterified fatty acid (NEFA) and serum L-lactate were collected on d -1, 1, 2, and 7. Data were analyzed via ProcMixed of SAS (experimental unit = steer; 15 to 20/treatment) as a 2 × 2 factorial, with fixed effects of DIET, DUR, and the interaction. Individual initial (d -42) BW was used as a covariate in BW analysis. Average DMI of d -11 to d -2 (pre-trucking) was used as a covariate in post-transit DMI analysis. Blood parameters were log-transformed and analyzed as repeated measures with repeated effect of day. Pre-transit (d -1) concentrations were used as a covariate. Pre-transit average daily gain (ADG) and dry matter intake (DMI) were greater (P ≤ 0.02) and feed efficiency (gain to feed; G:F) tended to be greater (P = 0.10) in Zn100 vs. Zn0. BW on d -1 and 7 (P = 0.01) was greater for Zn100 than Zn0. There was a DIET effect and DUR tendency on post-transit G:F where Zn0 was greater than Zn100 (P ≤ 0.01) and 18H tended to be greater than 8H (P = 0.05). 56-d post-transit ADG was least for Zn100-8H (DIET×DUR, P = 0.02). Post-transit DMI was greatest for Zn0-8H with Zn100-8H being the lowest and other treatments being not different (DIET × DUR, P = 0.04). Diet did not affect L- lactate or NEFA concentrations (P > 0.13). NEFA was greater for 18H vs. 8H on d 1 and 2 but less on d 7 (DUR×DAY, P < 0.01). There was a DUR×DAY effect (P ≤ 0.01) for L-Lactate where 8H tended to be greater than 18H on d 1, but by d 2 8H was lesser than 18H, and on d 7 they were not different. In conclusion, longer transit duration increases some indicators of muscle fatigue and Zn supplementation improved pre-transit performance. Receiving Zn supplementation after trucking also improved the post-transit performance of those not previously supplemented with Zn.

DIPG-02. A NOVEL STRATEGY TO RADIOSENSITISE DIFFUSE MIDLINE GLIOMAS VIA DUAL-TARGETING OF GLUCOSE METABOLISM

Abstract Diffuse Midline Gliomas (DMG) is the leading cause of brain tumor-related death in children. Currently, radiation is the only treatment that offers transient benefit but almost all DMG relapse due to radioresistance. Compared to normal brain tissue, DMG are hypo-perfused with tumor cells being exposed to hypoxia, a low oxygen microenvironment serves as a potent barrier to effective radiotherapy. Biguanides are hypoglycemic agents that can reduce the oxygen consumption rate (OCR) in mitochondria, thereby sparing more oxygen and alleviating hypoxia. Our previous study has shown that metformin significantly improves the radiosensitivity of DMG and extends survival in a patient-derived xenograft (PDX) model. In comparison with metformin, phenformin demonstrated greater efficacies in anti-proliferation, OCR and hypoxia inhibition, and radiosensitization in a panel of DMG cultures. These effects were possibly induced by phenformin through inhibition of mitochondrial complex I in DMG cells. The anti-tumor effect of phenformin was further enhanced by combining a second drug dichloroacetate that simultaneously attenuated phenformin-induced acidification. Specifically, the combination treatment induced higher levels of reactive oxygen species and DNA damage, which subsequently resulted in a much stronger effect in cell-cycle and proliferation arrest, apoptosis, and hypoxia inhibition. Metabolically, the co-treatment simultaneously targeted multiple pathways, which significantly reduced ATP production and further triggered metabolic catastrophe. RNA sequencing demonstrated significant alterations induced by the combination in cell-cycle, DNA repair, unfolded protein response and alternative energetic pathways. Furthermore, the combination treatment significantly improved the radiosensitivity of DMG cells, evidenced by higher levels of DNA damage, apoptosis, and clonogenic inhibition. Our preliminary in vivo data demonstrated a possible reduction in tumor burden following 4 weeks of combination treatment, with no elevation of serum L-lactate level in phenformin-treated groups. This therapeutic efficacy is currently being validated in multiple orthotopic DMG models with optimized treatment schedules.

Utility of Serum L-lactate in Identifying Ischemia in Acute Intestinal Obstruction: A Prospective Observational Study.

Introduction In cases of intestinal obstruction, increasing luminal dilatation compromises bowel wall perfusion, eventually resulting in intestinal ischemia and bowel necrosis in advanced cases. Elevated L-lactate, as a biomarker of ischemia, may indicate the presence of bowel ischemia in cases of obstruction. The objective of this study was to evaluate the value of serum L-lactate measurement in predicting the presence of intraoperatively observed intestinal ischemia in patients with acute intestinal obstruction. Methods Patients diagnosed with acute intestinal obstruction were prospectively studied over an 18-month period. Serum L-lactate values were assayed twice: at the time of presentation and following appropriate fluid resuscitation. Receiver operating characteristic (ROC) curve analysis was applied to determine the predictive value of serum L-lactate in detecting intestinal ischemia. Results One hundred forty-four cases of intestinal obstruction were included in this study, of which 91 underwent operative intervention. Intestinal ischemia was identified in 52 cases and categorized intra-operatively as reversible (n = 33) and irreversible (n = 19). ROC analysis showed a good predictive value of serum L-lactate after fluid resuscitation for irreversible intestinal ischemia (area under the curve (AUC) = 0.884, 95% confidence interval (CI), 0.812-0.956). An L-lactate cut-off of 19.1 mg/dL following fluid resuscitation was determined to have a sensitivity of 89.5%, a specificity of 72.9%, a positive predictive value of 46.6%, and a negative predictive value of 96.3% for gangrenous bowel. Conclusion Serum L-lactate is a good predictive tool for identifying intestinal ischemia during the management of intestinal obstruction. Serum L-lactate after resuscitation showed better predictive value for ischemic bowel.

Acute Mesenteric Ischemia in Critically Ill Patients. Possibilities of Laboratory Diagnostics. Systematic Literature Review and Meta-Analysis

Background Acute mesenteric ischemia (ami) is diagnosed in 1 case per 5,000–15,000 operations associated with elective abdominal surgical intervention and in 1 case of 1,000 emergency laparotomies associated with the acute abdomen clinical features. Non-occlusive disorders account for 20-30% of all cases of ami. The absence of pathognomonic symptoms and syndromes, as well as specific laboratory markers of ami, determines significant difficulties in the early diagnosis of this disease, especially in critically ill patients.Aim of study To identify the main laboratory markers of acute mesenteric ischemia applicable in the resuscitation and intensive care unit (ricu) based on a systematic literature review.Material and methods A systematic search and selection of publications was carried out in march-april 2021 in accordance with the prisma system checklist (prisma, preferred reporting items for systematic reviews and meta-analyzes). The search used two databases: the cochrane library of systematic reviews (https://www.cochranelibrary.com) and the pubmed bibliographic database (https://pubmed.ncbi.nlm.nih.gov). Key terms in the search parameters were: acute mesenteric ischemia; bowel necrosis predictors; laboratory diagnostics of mesenteric ischemia. Search parameters were limited to the year of publication (not later than 2015). The main results of the review included patients with an established diagnosis of acute mesenteric ischemia, indicating the level of laboratory parameters (ph of mixed venous blood, lactate, d-dimer, white blood count, mpv, i-fabp, serum marker and alpha-glutathione-s-transferase, indicators of the coagulation and hemostasis). Case reports and editorial letters were excluded from the search.Results The threshold value for serum l-lactate ranged from 1.05 mmol/l to 5.6 mmol/l. The sensitivity of serum lactate for the diagnosis of ami ranged from 34.7% (95% ci: 0.82–91.64%) to 89.51% (95.4% ci: 75.12–94.28%), and the specificity ranged from 47.3% (94.7% ci: 26.54–67.98%) to 94.5% (93.2% ci: 75.44–96.85%). The threshold level of d-dimer varied from 0.58 nmol/l to 7.84 nmol/l. The sensitivity of blood d-dimer for the diagnosis of ami was 72.6% (94% ci: 56.1–92.4%) to 99.7% (94% ci: 69.15–100%); the specificity ranged from 69% (95% ci: 7.41–33.63%) to 97.89% (95% ci: 90.42–98.1%). Parameters such as transaminases (ast, alt), mpv, ldh, d-lactate, serum amylase were not included in the review due to the lack of a sufficient number of studies.Conclusion Today, there is no highly specific laboratory marker that could be considered the “gold standard” in the laboratory diagnosis of acute mesenteric ischemia. The most promising in predicting ami are serum levels of l-lactate and d-dimer.

L-lactate kinetics after abdominal aortic surgery and intestinal ischemia – An observational cohort study

BackgroundPostoperative intestinal ischemia is a severe complication in abdominal aortic surgery. Early diagnosis is needed for adequate and timely treatment. We studied the postoperative kinetics of l-lactate in vascular patients to assess its value as a marker for early postoperative intestinal ischemia detection. Material and methodsWe performed a prospective non-randomized single-center observational cohort study in eighty elective patients, fifty operated on for abdominal aortic aneurysm (AAA) and thirty for aortoiliac occlusive disease (AIOD). Serum l-lactate was measured preoperatively, intraoperatively, and postoperatively at defined timepoints up to postoperative day 7. Intestinal ischemia was detected using MRI enterocolography. We have used univariate logistic regression and receiver operating characteristics curves for the evaluation of marker accuracy. ResultsWe recorded 6 cases of postoperative intestinal ischemia (7.5%), five non-transmural and one transmural. Two patients died because of this complication (mortality 33%). The comparison of AAA and AIOD cohorts showed a significant difference in l-lactate levels at one intraoperative timepoint, which was attributable to procedure differences. The only preoperative factor associated with higher l-lactate levels at some timepoints was chronic kidney disease. Patients suffering postoperative intestinal ischemia had elevated serum l-lactate levels at multiple timepoints. The most accurate timepoint for diagnosis was 24 h after the declamping of the vascular reconstruction (DC24H), the second was 10 min after declamping. Sensitivity, specificity, positive and negative predictive values at timepoint DC24H were 100%, 82%, 32%, and 100%, respectively. ConclusionSerum l-lactate levels might help in the early detection of postoperative intestinal ischemia after aortic surgery if proper timepoints are used. Cutoff values need to be established in large-scale prospective studies.

Systemic implications of metallic foreign body syndrome in dairy cattle

This study aimed to evaluate the systemic implications of 37 cattle with traumatic reticulitis, evaluating clinical, laboratory, ultrasonographic and necroscopic changes. A clinical, laboratory and ultrasonographic examination was performed, and the animals were distributed in reticuloperitonitis (GI; n=21) and reticulopericarditis (GII; n=16) traumatic, based on necropsy findings. Blood samples were taken for haematological tests, serum total protein, albumin, globulin, gamma glutamyltransferase (GGT), aspartate aminotransferase (AST), glutamate dehydrogenase (GLDH), creatinine, urea, cortisol, creatine kinase (CK), creatine kinase-MB (CK-MB), cardiac troponin-I (cTn-I), plasma glucose and L-lactate. The abdominocentesis was productive in eight GI (n=8) and seven GII (n=7) animals, allowing the evaluation of physical, cytological and biochemical characteristics of the peritoneal fluid as a total protein, albumin, GLDH, AST, GGT, glucose and L-lactate. Changes in behavior, appetite, dehydration and temperature were observed, most expressive in GII. Hematology showed neutrophilic leukocytosis with regenerative left shift and hyperfibrinogenemia in both groups. Increased globulin, L-lactate concentration and serum GGT, GLDH, CK and CK-MB activity were observed, as well as significant elevation of cTnI (p=0.0190) in GII. In the peritoneal fluid exudate was observed in both groups and a higher concentration of L-lactate in relation to plasma. Ultrasound revealed retocular, cardiac, hepatic and splenic abnormalities. The anatomopathological lesions confirmed the ultrasound findings of both groups. The understanding of the syndrome helps in the diagnosis, as well as the adoption of preventive measures, minimizing the economic impact caused to the dairy cattle breeding.

Hypoxic-ischemic enterocolitis: a proposal of a new terminology for early NEC or NEC-like disease in preterm infants, a single-center prospective observational study.

We aimed to investigate the role of hypoxia-ischemia in the pathophysiology of early NEC/NEC like disease (ENEC) and classic NEC/NEC like disease (CNEC) in preterm infants. In this pilot study, preterm infants who developed the clinical symptoms and signs of NEC/NEC like disease were divided into two groups as early (≤ 7 days, ENEC) or late (> 7 days, CNEC) groups. Beside clinical variables, serum L-lactate, endothelin-1 (ET-1), platelet activating factor (PAF), and intestinal fatty acid binding protein (I-FABP) levels were measured from umbilical/peripheric venous blood in the first hour of life and during the clinical presentation in all groups. A total of 86 preterm infants were enrolled in the study. In the ENEC group, the incidences of fetal umbilical artery Doppler velocimetry abnormalities, IUGR, and delayed passage of first meconium were higher. In addition, mean levels of L-lactate, ET-1, PAF, and I-FABP were higher in the first hour of life.Conclusion: Our study firstly showed that the dominant pathophysiological factor of ENEC is prenatal hypoxic-ischemic event where intestinal injury and inflammation begin in-utero and become clinically apparent in the first week of life. Therefore, we propose a new term "Hypoxic-Ischemic Enterocolitis (HIEnt)" for the definition of ENEC in preterm infants with prenatal hemodynamic disturbances and IUGR. This new sight can provide individualized preventive and therapeutic strategies for preterm infants.What is Known:• The pathophysiology of early necrotizing enterocolitis (NEC) or NEC-like disease which is seen in the first week of life seems different than classic necrotizing enterocolitis (CNEC) which is always seen after the first week of life.What is New:• This study suggests that perinatal hypoxic-ischemic process with inflammation is the point of origin of fetal intestinal injury leading to ENEC.• We propose a new term "Hypoxic-Ischemic Enterocolitis (HIEnt)" for the definition and differentiation of this unique clinical entity.

Serum d- and l-lactate, pyruvate and glucose levels in individuals with at-risk mental state and correlations with clinical symptoms.

Little information exists on the peripheral metabolite levels in individuals with at-risk mental state who meet the criteria for a high-risk state of psychosis. Here, we aimed to investigate serum levels of glucose, pyruvate and d- and l-lactate, which may act as a signalling molecule for learning and memory in neuronal cells. High performance liquid chromatography or commercial kits were used to assess serum metabolites in individuals with attenuated psychosis symptoms of at-risk mental state (n = 24, men = 12) who were not receiving antipsychotics. The metabolite levels of these individuals were compared with those of age- and sex-matched healthy individuals (controls, n = 23, men = 11). Correlations between the metabolites and clinical symptoms of at-risk mental state were also examined. Individuals with at-risk mental state had higher serum glucose levels than did controls (P = 2.18 × 10-3 ), while no significant difference in pyruvate levels were observed between the groups. Individuals with at-risk mental state had significantly lower serum l-lactate levels than did controls (P = 6.31 × 10-5 ), while no differences in d-lactate levels were observed. Furthermore, a negative correlation was identified between serum l-lactate levels and Positive and Negative Syndrome Scale negative symptoms scores (r = -0.5651, P = 4.01 × 10-3 ) in individuals with at-risk mental state. We found that, compared with controls, individuals with at-risk mental state have reduced serum l-lactate levels, which may predate psychosis onset, and may be involved in the related negative symptoms.

Can serum L-lactate, D-lactate, creatine kinase and I-FABP be used as diagnostic markers in critically ill patients suspected for bowel ischemia

BackgroundThe prognostic value of biochemical tests in critically ill patients with multiple organ failure and suspected bowel ischemia is unknown.MethodsIn a prospective observational cohort study intensive care patients were included when the attending intensivist considered intestinal ischemia in the diagnostic workup at any time during intensive care stay. Patients were only included once. When enrolment was ended each patient was classified as ‘proven intestinal ischemia’, ‘ischemia likely’, ‘ischemia unlikely’ or ‘no intestinal ischemia’. Proven intestinal ischemia was defined as the gross disturbance of blood flow in the bowel, regardless of extent and grade. Classification was based on reports from the operating surgeon, pathology department, endoscopy reports and CT-scan. Lactate dehydrogenase (LDH), creatine kinase (CK), alanine aminotransferase (ALAT), L-lactate were available for the attending physician. D-lactate and intestinal fatty acid binding protein (I-FABP) were analysed later in a batch. I-FABP was only measured in patients with proven ischemia or no ischemia.ResultsFor 44 of the 120 included patients definite diagnostic studies were available. 23/44 patients (52%) had proven intestinal ischemia as confirmed by surgery, colonoscopy, autopsy and/or histopathological findings. LDH in these patients was 285 U/l (217–785) vs 287 U/l (189–836) in no-ischemia; p = 0.72. CK was 226 U/l in patients with proven ischemia (126–2145) vs 347 U/l (50–1427), p = 0.88. ALAT was 53 U/l (18–300) vs 34 U/l (14–34), p-0,56. D-lactate 0.41 mmol/l (0.11-0.75) vs 0.56 mmol/l (0.27-0.77), p = 0.46. L-lactate 3.5 mmol/l (2.2-8.4) vs 2.6 mmol/l (1.7-3.9), p = 0.09. I-FABP 2872 pg/ml (229–4340) vs 1020 pg/ml (239–5324), p = 0.98. Patient groups proven and likely ischemia together compared to unlikely and no-ischemia together showed significant higher L-lactate (p = 0.001) and higher D-lactate (p = 0.003).ConclusionsMeasurement of LDH, CK, and ALAT did not discriminate critically ill patients with proven intestinal ischemia from those with definite diagnosis no-ischemia. However, L-lactate and D-lactate levels were higher in patients with proven or likely ischemia and need further study just as I-FABP.

Blood concentrations of D- and L-lactate in healthy rabbits.

To determine whole blood and serum concentrations of l-lactate and serum concentrations of d-lactate in healthy rabbits and compare three methods of analysis for l-lactate measurement. Prospective study using 25 rabbits. Concentrations of whole blood l-lactate were measured using a portable analyser and a blood gas analyser. The remainder of the sample was allowed to clot for centrifugation. Serum was stored at -20°C for determination of l- and d- lactate by high-performance liquid chromatography. d-lactate values by high-performance liquid chromatography were 0 · 17 ± 0 · 08 mmol/L. l-lactate values were 5 · 1 (±2 · 1) mmol/L by high-performance liquid chromatography, 6 · 9 (±2 · 7) mmol/L with the portable analyser and 7 · 1 (±1 · 6) mmol/L with the blood gas analyser. No significant difference (P > 0 · 05) was found between the two analysers. Significant difference existed between serum l-lactate values obtained by high-performance liquid chromatography and the whole blood values obtained with the blood gas analyser (P < 0 · 01) and portable analyser (P < 0 · 05). Serum concentrations of d-lactate in healthy rabbits are in the range of those of other mammals. l-lactate values in healthy rabbits are higher compared with other mammals. Good correlation was found between the portable and blood gas analysers for whole blood l-lactate measurement in healthy rabbits.

Trans‐10,cis‐12 Conjugated Linoleic Acid Enhances Endurance Capacity by Increasing Fatty Acid Oxidation and Reducing Glycogen Utilization in Mice

The supplementation of conjugated linoleic acid (CLA) has been shown to improve endurance by enhancing fat oxidation during exercise in rodents and humans. This study was designed to investigate the isomer-specific effects of CLA on endurance capacity and energy metabolism in mice during exercise. Male 129Sv/J mice were divided into three dietary groups and fed treatment diet for 6 weeks; control, 0.5 % cis-9,trans-11 (c9,t11) CLA, or 0.5 % trans-10,cis-12 (t10,c12) CLA. Dietary t10,c12 CLA induced a significant increase in maximum running time and distance until exhaustion with a dramatic reduction of total adipose depots compared to a control group, but there were no significant changes in endurance with the c9,t11 CLA treatment. Serum triacylglycerol and non-esterified fatty acid concentrations were significantly lower in the t10,c12 fed mice after exercise compared to control and the c9,t11 CLA fed-animals. Glycogen contents in livers of the t10,c12 fed-mice were higher than those in control mice, concomitant with reduction of serum L-lactate level. There were no differences in non-exercise physical activity among all treatment groups. In addition, the mRNA expression levels of carnitine palmitoyl transferase 1β, uncoupling protein 2 and peroxisome proliferator-activated receptor δ (PPARδ) in skeletal muscle during exercise were significantly up-regulated by the t10,c12 CLA but not the c9,t11 CLA. These results suggest that the t10,c12 CLA is responsible for improving endurance exercise capacity by promoting fat oxidation with a reduction of the consumption of stored liver glycogen, potentially mediated via PPARδ dependent mechanisms.

Does lactate measurement performed on admission predict clinical outcome on the intensive care unit? A concise systematic review

There is a need for practical, efficient and effective prognostic markers for patients admitted to the intensive care unit (ICU) with sepsis, to identify patients at highest risk and guide and monitor treatment. Although many biomarkers and scoring systems have been advocated, none have yet achieved this elusive combination. Most ICUs already use blood lactate concentrations to monitor patients but the evidence base for this application is unclear. A systematic review of the last five years of evidence of effectiveness of lactate measurement in prediction of outcome in ICUs was performed. It was found that there is a lack of high-quality evidence, and no specific studies of prognostic accuracy. D- or L-Lactate concentrations measured in plasma, serum, whole blood or colonic washings were raised at admission in almost all patient groups, and were higher in patient groups who had the worst outcomes (in-hospital mortality, sequential organ failure). However, there was significant overlap in individual concentrations measured in those who died within 28 days of admission, or who developed multiple organ failure, and those who did not. For serum L-lactate concentrations, no specific cut-off value capable of predicting in-hospital mortality or sequential organ failure could be recommended. The evidence reviewed suggested that whole blood, plasma or serum lactate measurement could not provide specific prognostic information for individual patients. There may be a role for monitoring for normalization of serum D- or L-lactate concentrations during goal-directed therapy in the ICU but further good-quality studies are needed. Measurement of the D-lactate stereoisomer shows promise, such that further studies are warranted.

Influence of grain processing in regard to serum metabolites and enzymes for finishing bull calves

This study compared two grain processing methods that are widely used for beef cattle, grinding and steam pelleting, with respect to serum metabolic parameters: glucose, non-esterified fatty acids (NEFA), serum urea nitrogen (SUN), total serum protein (TSP), albumin, L-lactate, aspartate aminotransferase (AST), y-glutamyltransferase (GGT) and amylase. Ten Belgian Blue bull calves were allotted randomly to each of two experimental groups: PF, fed pelleted concentrate, and GF, fed ground concentrate. During the 77-day study most parameters underwent significant variation in time, increasing only numerically serum values of total protein, albumin, AST and amylase, while serum glucose, NEFA and GGT decreased numerically. Statistically significant differences were found only between groups PF and GF for creatinine (higher in group PF, in relation with its greater average body weight) and urea nitrogen, which for unknown causes fluctuated in opposite directions in the two groups throughout most of the study and attributable to changes in ruminai protein digestion. Neither serum glucose nor L-lactate were affected by treatment of grains.

Effects of supplementation with plant extract product containing carvacrol, cinnamaldehyde and capsaicin on serum metabolites and enzymes during the finishing phase of feedlot-fed bull calves

This study investigated the in vivo effects of a commercial blend of plant extracts (carvacrol, cinnamaldehyde and capsaicin) on serum metabolic parameters closely connected with energy and protein metabolism (glucose; l-lactate; non-esterified fatty acids, NEFA; urea nitrogen, SUN; creatinine; total protein, TSP) and enzymes associated with hepatic function (aspartate-aminotransferase, AST and gamma-glutamyl transferase, GGT) in finishing-stage Belgian Blue bull calves maintained in a commercial feedlot. Monitoring was performed over 86 days in 24 animals randomly allotted to two groups: (1) a control group (CTR, no supplementation; n=10), and (2) a group receiving dietary supplementation with a commercial blend of plant extracts (PEX, 100mg/kg DM of concentrate; n=14). Under the conditions of our study, supplementation with the commercial blend did not give detrimental effects, but the opposite: the decrease in serum l-lactate, NEFA and creatinine levels and the increase in SUN concentrations; suggests an improvement in the energy status and protein turnover of the supplemented animals.

The Serum Metabolite Response to Diet Intervention with Probiotic Acidified Milk in Irritable Bowel Syndrome Patients Is Indistinguishable from that of Non-Probiotic Acidified Milk by 1H NMR-Based Metabonomic Analysis

The effects of a probiotic acidified milk product on the blood serum metabolite profile of patients suffering from Irritable Bowel Syndrome (IBS) compared to a non-probiotic acidified milk product was investigated using 1H NMR metabonomics. For eight weeks, IBS patients consumed 0.4 L per day of a probiotic fermented milk product or non-probiotic acidified milk. Both diets resulted in elevated levels of blood serum L-lactate and 3-hydroxybutyrate. Our results showed identical effects of acidified milk consumption independent of probiotic addition. A similar result was previously obtained in a questionnaire-based evaluation of symptom relief. A specific probiotic effect is thus absent both in the patient subjective symptom evaluations and at the blood serum metabolite level. However, there was no correspondence between symptom relief and metabolite response on the patient level.

The influence of chemical form on the effects of supplementary malate on serum metabolites and enzymes in finishing bull calves

This study investigated the effects of free malic acid and a commercial malate salt on serum metabolic parameters in finishing-stage Belgian Blue bull calves maintained in a commercial feedlot. Serum levels of glucose, non-esterified fatty acids (NEFA), β-Hydroxibutirate (BHBT) urea nitrogen (SUN), creatinine, total protein (TSP), L-lactate, aspartate aminotransferase (AST) and gamma glutamyl transferase (GGT) were monitored over 86days in 38 animals randomly allotted to three groups: MA (supplementation of feed with 4-g DL-malic acid per kg on a dry mass (DM) basis; 14 animals), MS (supplementation of feed with 4g of a commercial disodium/calcium DL-malic acid salt per kg DM; 14 animals), and C (controls with no malate supplement; 10 animals). All the parameters considered except SUN lay within the physiological ranges for intensively reared beef, possibly due to the high crude protein (CP) content of the diet and the forage fiber source (barley straw). However, animals fed either form of malate had lower serum L-lactate and creatinine levels than those that did not receive this supplement, and their NEFA levels fell over time instead of rising. The only parameters differing between the free acid and salt groups were SUN and BHBT, which for unknown reasons, were higher in group MA than in either controls or group MS. That SUN was higher in group MA than in group C is attributed to its favoring CP-degrading ruminal flora. That BHBT was higher in group MA than in groups MS and C could be due to that the acid form can promote butyrate synthesis in rumen.

Hunting down a double gap metabolic acidosis

Double gap metabolic acidosis occurs in the setting of unmeasured active osmoles in the serum (osmolal gap) and anion gap (AG) metabolic acidosis. We describe a 67-year-old woman with acute respiratory failure on mechanical ventilator from pneumonia and anuric acute on chronic renal failure (urea nitrogen 21.4 mmol/L, creatinine 530.4 micromol/L) requiring haemodialysis (HD). On hospital day 5, she was found to have progressive metabolic acidosis (serum pH 7.16, PCO(2) 4.38 kPa, HCO(3)(-) 12.1 mmol/L and AG 21 mmol/L). There was no evidence of hypoxaemia, hypoperfusion or haemodynamic instability. Normal serum ketone and L-lactate but high serum osmolal gap (89.4 mmol/kg) was detected. A search for toxic alcohols revealed a high serum propylene glycol (PG 32.9 mmol/L), a stabilizing solvent for intravenous formulations of lorazepam, which was being used as sedation for mechanical ventilation. Unexpectedly, serum L- and D-lactate as metabolites of PG were not elevated. Although extended HD for eight hours completely removed serum PG and the osmolal gap, the predialysis high AG metabolic acidosis persisted, potentially related to hypercatabolism and anuric renal failure. PG should be in the differential diagnosis of the disorders with high osmolar gap and may not always be associated with L- or D-lactic acidosis.

Case 5—2009 Severe Lactic Acidosis During Cardiac Surgery

LACTIC ACIDOSIS IS A metabolic acidosis that occurs as a result of elevated serum L-lactate levels. It is classified according to the presence or absence of associated tissue hypoxia. In type-A lactic acidosis, impaired tissue oxygenation leads to increased anaerobic metabolism and an excessive production of pyruvate (which is then converted to lactate). Shock, hypoxia, heart failure, and/or hypovolemia are common causes of type-A lactic acidosis. Type-B lactic acidosis is characterized by an absence of overt tissue hypoxia; causes include toxin-induced impairment of cellular metabolism (cyanide, metformin, anti-HIV medications), thiamine deficiency, malignancy, alcoholism, and liver failure.

Supplementation with plant extracts (carvacrol, cinnamaldehyde and capsaicin): Its effects on acid-base status and productive performance in growing/finishing bull calves

This study investigated the in vivo effects of a commercial blend of plant extracts (carvacrol, cinnamaldehyde and capsaicin) on blood acid-base balance and serum lactate levels in a 148-day feedlot experimentwith 24 double-muscled Belgian Blue bull calves. Animals were allotted randomly to one of two experimental groups: 1) a control group (C, no supplementation; n = 10), and 2) a group receiving dietary supplementation with a combination of plant extracts (PE, 100 mg per kg DM of concentrate; n = 14). All animals received a high-grain ration, typical of diets fed commercially to feedlot cattle in Spain, consisting mainly of barley plus other components in proportions depending on the production phase. Production data (weight, DMI, ADG and feed-to-gain ratio) were recorded, and venous blood pH, pCO2, HCO3(-), Base Excess -BE- and serum L-lactate were determined. Apparently, beneficial effects of supplementation on production parameters were observed in both growing and finishing periods, though statistically significant effects were only observed in the finishing period. As regards blood parameters, no significant effects of supplementation (or the supplementation x time interaction) were observed, except for an effect on blood pH in the growing period, when supplemented animals showed significantly higher values than controls. A beneficial supplementation x time interactive effect was observed on serum L-lactate levels: from the first week of the study until the end, supplemented animals showed significantly lower levels than controls. These in vivo results support the utility of this dietary supplement in feedlot cattle receiving a barley-based high-grain diet.

생쥐에서 가정분진 입자로 인한 항원관련 호산구성 기도 염증과 기도 과민성의 증대

The number of patient with allergic asthma and atopy have increased in the cities of Korea steadily. In order to elucidate the primary factor, we investigated whether the house dust particles collected from an apartment of the middle classes has promoting effects of allergen-related airway inflammation and airway hyperresponsiveness. Mice were treated with 0.1 mL of 1 mg/mL of house dust particles suspension by intratracheal instillation once weekly for 10 weeks combined with ovalalbumin (OVA) sensitization. Intratracheal instillation of house dust particles and OVA sensitization caused an increase in the level of serum L-lactate dehydrogenase (LDH), immunoglobulun-E (IgE) and histamine, and an elevation in respiratory resistance. It also enhanced infiltration of eosinophils in the bronchoalveolar lavage fluid (BALF) of mice, IgE and eotaxin expression in blood, and T helper type 2 cell derived cytokine levels such as of interleukin (IL)-4, IL-13 and IL-5 in the BALF. However, it did not influence T helper type 1 cytokine such as interferon-gamma in the BALF. These results indicate that house dust particles elevate allergen-related airway inflammation and airway hyperresponsiveness in mice and may play an important role in the aggravation of asthma and atopy in Korea.