Interpretation of the effects of rumen acidosis on the gut microbiota and serum metabolites in calves based on 16S rDNA sequencing and non-target metabolomics.

Introduction: Rumen acidosis is one of the most common diseases in beef cattle. It severely affects the normal development of calves and poses a significant threat to the farming industry. However, the influence of rumen acidosis on the gut microbiota and serum metabolites of calves is currently unclear. Objective: The aim of this study is to investigate the changes in the gut microbiota and serum metabolites in calves after rumen acidosis and analyse the correlation. Methods: Eight calves were selected as the rumen acidosis group, and eight health calves were selected as the healthy group. The faecal gut microbiota and serum metabolites of calves were detected respectively using 16S rDNA high-throughput sequencing and non-target metabolomics. The correlation between gut microbiota and serum metabolites was analyzed by Spearman correlation analysis. Results: Differential analysis of the diversity and composition of gut microbiota between eight male healthy (Health) and eight male rumen acidosis (Disease) calves revealed that rumen acidosis increased the abundance of the gut microbiota in calves. At the phylum level, compared to the Healthy group, the relative abundance of Proteobacteria in the Disease group significantly decreased (P<0.05), while the relative abundance of Desulfobacterota significantly increased in the Disease group (P<0.05). At the genus level, compared to the Disease group, the relative abundance of Alloprevotella, Muribaculaceae, Succinivibrio, Prevotella, Agathobacter and Parabacteroides significantly increased in the Healthy group (P<0.05), while the relative abundance of Christensenellaceae_R-7 and Monoglobus significantly decreased in the Healthy group (P<0.05). Differential analysis results showed the Healthy group had 23 genera with higher abundance, while the Disease group had 47 genera with higher abundance. Serum metabolomics results revealed the differential metabolites associated with rumen acidosis, including nicotinamide, niacin, L-glutamic acid and carnosine, were mainly enriched in the nicotinate and nicotinamide pathway and the histidine pathway. Conclusion: The occurrence of rumen acidosis can induce changes in the gut microbiota of calves, with a significant increase of the Christensenellaceae_R-7 genus and a significant decrease of Prevotella and Succinivibrio genera. In addition, the occurrence of rumen acidosis can also induce changes in serum metabolites including niacin, niacinamide, L-glutamine, and carnosine, which may serve as the diagnostic biomarkers of rumen acidosis of calves.

Fat overload syndrome following intravenous lipid emulsion administration as antidote in suspected anesthetic intoxication: insights from a clinical and forensic case experience.

Abstract: Medication errors pose significant risks to patients' health, representing a relevant social and economic issue for the healthcare system. This study focuses on the life-threatening consequences of an overdose of intravenous lipid emulsion (ILE), used as an antidote for suspected bupivacaine intoxication in a young woman undergoing hip surgery. Shortly after administration of the local anesthetic, the woman experienced cardiac arrest and was admitted to the intensive care unit with severe respiratory failure, metabolic acidosis and deep coma. Despite medical intervention, her condition worsened, leading the medical team to administer ILE for suspected bupivacaine intoxication. The patient's condition did not improve and ultimately resulted in death. The autopsy highlighted a widespread presence of oily material in the vascular system, compatible with an overdose of ILE. At a checking, medical records reported a dose of ILE that was 4-fold higher than the recommended dose in this off-label indication. This case report highlights the important need for healthcare professionals to understand the risks of using ILE as an antidote. Adequate monitoring of these "sentinel events" and their critical evaluation can lead to the implementation of specific clinical risk management protocols to reduce the risk for the patient and contain healthcare costs.

Not only Van Gogh: a case of BRASH syndrome with concomitant digoxin toxicity.

BACKGROUND: Bradycardia, renal failure, atrioventricular (AV) node blocking, shock, and hyperkalemia syndrome is a potentially life-threatening clinical condition characterized by bradycardia, renal failure, atrioventricular (AV) node blocking, shock, and hyperkalemia. It constitutes a vicious circle in which the accumulation of pharmacologically active compounds and hyperkalemia lead to hemodynamic instability and heart failure. CASE PRESENTATION: A 66-year-old Caucasian female patient was admitted to the emergency department presenting with fatigue and bradycardia. Upon examination, the patient was found to be anuric and hypotensive. Laboratory investigations revealed metabolic acidosis and hyperkalemia. Clinical evaluation suggested signs of digoxin toxicity, with serum digoxin concentrations persistently elevated over several days. Despite the implementation of antikalemic measures, the patient's condition remained refractory, necessitating renal dialysis and administration of digoxin immune fab. CONCLUSION: Bradycardia, renal failure, atrioventricular (AV) node blocking, shock, and hyperkalemia syndrome is a life-threatening condition that requires prompt management. It is important to also consider potential coexisting clinical manifestations indicative of intoxication from other pharmacological agents. Specifically, symptoms associated with the accumulation of drugs eliminated via the kidneys, such as digoxin. These manifestations may warrant targeted therapeutic measures.

Association between decision-to-delivery time and neonatal outcomes: a systematic review and meta-analysis.

BACKGROUND: Decision-to-delivery time (DDT), a crucial factor during the emergency caesarean section, may potentially impact neonatal outcomes. This study aims to assess the association between DDT and various neonatal outcomes. METHODS: A comprehensive search of PubMed, Scopus, Cochrane Library, and Google Scholar databases was conducted. A total of 32 eligible studies that reported on various neonatal outcomes, such as Apgar score, acidosis, neonatal intensive unit (NICU) admissions and mortality were included in the review. Studies were selected based on predefined eligibility criteria, and a random-effects inverse-variance model with DerSimonian-Laird estimate of tau² was used for meta-analysis. Heterogeneity and publication bias were assessed using I² statistics and Egger's test, respectively. RESULTS: The meta-analysis revealed a significant association between DDT < 30 min and increased risk of Apgar score < 7 (OR 1.803, 95% CI: 1.284-2.533) and umbilical cord pH < 7.1 (OR 4.322, 95% CI: 2.302-8.115), with substantial heterogeneity. No significant association was found between DDT and NICU admission (OR 0.982, 95% CI: 0.767-1.258) or neonatal mortality (OR 0.983, 95% CI: 0.565-1.708), with negligible heterogeneity. Publication bias was not detected for any outcomes. CONCLUSIONS: This study underscores the association between shorter DDT and increased odds of adverse neonatal outcomes such as low Apgar scores and acidosis, while no significant association was found in terms of NICU admissions or neonatal mortality. Our findings highlight the complexity of DDT's impact, suggesting the need for nuanced clinical decision-making in cases of emergency caesarean sections.

Demystifying normal-anion-gap metabolic acidosis: pathophysiology, aetiology, evaluation and diagnosis.

Normal-anion-gap metabolic acidosis (NAGMA) is a common but often under-recognised and poorly understood condition, especially by less-experienced clinicians. In adults, NAGMA might be an initial clue to a more significant underlying pathology, such as autoimmune diseases, hypergammaglobulinemia or drug toxicities. However, identifying the aetiology can be challenging due to the diverse processes involved in the development of acidosis. A better understanding of the pathophysiology of NAGMA can help treating physicians suspect and evaluate the condition early and reach the correct diagnosis. This article provides an overview of renal acid-base regulation, discusses the pathophysiological processes involved in developing NAGMA and provides a framework for evaluation to reach an accurate diagnosis.

Base excess (BE): reloaded.

The base excess value (BE, mmol/L), not standard base excess (SBE), correctly calculated including pH, pCO2 (mmHg), sO2 (%) and cHb (g/dl) is a diagnostic tool for several in vivo events, e.g., mortality after multiple trauma or shock, acidosis, bleeding, clotting, artificial ventilation. In everyday clinical practice a few microlitres of blood (arterial, mixed venous or venous) are sufficient for optimal diagnostics of any metabolic acidosis or alkalosis.The same applies to a therapeutic tool-then referred to as potential base excess (BEpot)-for several in vitro assessments, e.g., solutions for infusion, sodium bicarbonate, blood products, packed red blood cells, plasma. Thus, BE or BEpot has been a parameter with exceptional clinical significance since 2007.

Commentary: Is Polyethylene Glycol Toxicity From Intravenous Methocarbamol Fact or Fiction?

Methocarbamol is an antispasmodic muscle relaxant and was the fourth most-prescribed muscle relaxant by volume in the United States in 2021. Intravenous (IV) methocarbamol contains the excipient, polyethylene glycol (PEG), which has been implicated in metabolic acidosis and nephrotoxicity. Intravenous methocarbamol was first approved by the US Food and Drug Administration in 1959 and at that time the IV methocarbamol prescribing information warned of PEG-associated adverse drug events in patients living with renal impairment; however, the manufacturer acknowledged data were lacking to objectively support this claim. Clinicians prescribing and dispensing IV methocarbamol may encounter the warning for PEG-associated metabolic acidosis and nephrotoxicity without knowing the potential risks, or lack thereof, supporting or disavowing this phenomenon. This commentary debates the merits supporting and arguments refuting PEG-associated metabolic acidosis and nephrotoxicity in patients treated with IV methocarbamol.

Autoimmune polyglandular syndrome with shock and high anion gap metabolic acidosis.

Autoimmune polyglandular syndrome (APS) is a rare group of immune-mediated disorders, which are typically, but not exclusively, related to the presence of endocrine abnormalities. APS type 2 is the most common subtype of the syndrome, more often observed in adulthood, with a characteristic clinical triad, which includes adrenal insufficiency, autoimmune thyroiditis and diabetes mellitus type 1. Adrenal insufficiency is an essential and necessary clinical manifestation of the syndrome, as it is observed in 100 % of the cases, while it can be accompanied by hyperchloremic metabolic acidosis. Herein, we present a 23 years-old patient with adrenal insufficiency in the context of autoimmune polyglandular syndrome type 2 with coexisting autoimmune thyroiditis and metabolic acidosis with an increased anion gap attributed to prolonged malnutrition. Additionally, we analyze the main clinical features of adrenal insufficiency, which is a central component of autoimmune polyglandular syndrome; highlight characteristics that differentiate the major APS subtypes.

Association between Doppler assessment and secondary cesarean delivery for intrapartum fetal compromise in small-for-gestational-age fetuses.

PURPOSE: To elucidate the association between arterial and venous Doppler ultrasound parameters and the risk of secondary cesarean delivery for intrapartum fetal compromise (IFC) and neonatal acidosis in small-for-gestational-age (SGA) fetuses. METHODS: This single-center, prospective, blinded, cohort study included singleton pregnancies with an estimated fetal weight (EFW) < 10th centile above 36 gestational weeks. Upon study inclusion, all women underwent Doppler ultrasound, including umbilical artery (UA) pulsatility index (PI), middle cerebral artery (MCA) PI, fetal aortic isthmus (AoI) PI, umbilical vein blood flow (UVBF), and modified myocardial performance index (mod-MPI). Primary outcome was defined as secondary cesarean section due to IFC. RESULTS: In total, 87 SGA pregnancies were included, 16% of which required a cesarean section for IFC. Those fetuses revealed lower UVBF corrected for abdominal circumference (AC) (5.2 (4.5-6.3) vs 7.2 (5.5-8.3), p = 0.001). There was no difference when comparing AoI PI, UA PI, ACM PI, or mod-MPI. No association was found for neonatal acidosis. After multivariate logistic regression, UVBF/AC remained independently associated with cesarean section due to IFC (aOR 0.61 [0.37; 0.91], p = 0.03) and yielded an area under the curve (AUC) of 0.78 (95% CI, 0.67-0.89). A cut-off value set at the 50th centile of UVBF/AC reached a sensitivity of 86% and specificity of 58% for the occurrence of cesarean section due to IFC (OR 8.1; 95% CI, 1.7-37.8, p = 0.003). CONCLUSION: Low levels of umbilical vein blood flow (UVBF/AC) were associated with an increased risk among SGA fetuses to be delivered by cesarean section for IFC.

Blood chloride abnormalities in diarrheic neonatal calves with metabolic acidosis.

The present study investigated the prevalence of blood chloride (Cl) abnormalities in diarrheic neonatal calves with metabolic acidosis and attempted to identify the most relevant electrolyte abnormality to these abnormalities. A retrospective analysis was conducted on the medical records of 157 diarrheic neonatal calves aged 10.3 ± 4.2 days old with metabolic acidosis. Hypochloremia, normochloremia, and hyperchloremia were observed in 8.9% (14/157), 43.3% (68/157), and 47.8% (68/157), respectively, of diarrheic calves with metabolic acidosis. This distribution remained similar regardless of age (under 8 days or 8 days and older). Furthermore, a multiple logistic regression analysis showed that variations in values for blood sodium [Na (regression coefficients 0.877; 95% confidence interval (CI) 13.977-134.195; P<0.01)], pH (regression coefficients -10.719; 95% CI -19.076- -2.362; P<0.05), and bicarbonate [HCO3- (regression coefficients -0.555; 95% CI -0.820- -0.290; P<0.01)] were associated with blood Cl abnormalities. The present results revealed that blood Na concentrations were more strongly associated with blood Cl concentrations than blood pH and HCO3- values. In the present study, diarrheic calves with hyperchloremia were characterized by normonatremia and extremely severe metabolic acidosis.

Metabolic Acidosis in CKD: Pathogenesis, Adverse Effects, and Treatment Effects.

Metabolic acidosis is a frequent complication of chronic kidney disease and is associated with a number of adverse outcomes, including worsening kidney function, poor musculoskeletal health, cardiovascular events, and death. Mechanisms that prevent metabolic acidosis detrimentally promote further kidney damage, creating a cycle between acid accumulation and acid-mediated kidney injury. Disrupting this cycle through the provision of alkali, most commonly using sodium bicarbonate, is hypothesized to preserve kidney function while also mitigating adverse effects of excess acid on bone and muscle. However, results from clinical trials have been conflicting. There is also significant interest to determine whether sodium bicarbonate might improve patient outcomes for those who do not have overt metabolic acidosis. Such individuals are hypothesized to be experiencing acid-mediated organ damage despite having a normal serum bicarbonate concentration, a state often referred to as subclinical metabolic acidosis. Results from small- to medium-sized trials in individuals with subclinical metabolic acidosis have also been inconclusive. Well-powered clinical trials to determine the efficacy and safety of sodium bicarbonate are necessary to determine if this intervention improves patient outcomes.

Lyophilized rumen fluid as a ruminal fermentation modifier in high grain-fed acidotic goats.

Rumen cud transfaunation re-establishes rumen micro environment and improves fermentation in recipient animals affected with digestive disorders. Preserving rumen cud or fluid will increase its availability for the treatment of rumen fermentation disorders, without having to maintain donor animals. Rumen fluid collected from healthy goats, fed standard ration having roughage 70% and concentrate 30%, was lyophilized (prefreezing -80 °C, 48 h; lyophilization -45 °C, 32 h) using 5% glycerol as cryoprotectant. The 16 S metagenome analysis of the lyophilized rumen fluid (LRF) revealed an abundance of Prevotella (33.2%). Selenomonas ruminantium (1.87%) and Megasphaera elsdenii (0.23%) were also present. Twenty-four goats having history of high grain feeding and exhibiting clinical symptoms of rumen fermentation disorders were randomly distributed into either one of the two treatment groups viz., T1 = oral administration of LRF 31 g/animal/day and T2 = oral administration of sodium bicarbonate (SB) 15 g/animal/day. Post intervention LRF and SB, improved animal body condition, feed intake, fecal consistency, elevated the ruminal pH at 48 h, reduced propionate and lactate at 48 h, reduced total volatile fatty acids (TVFA) and ammonia nitrogen at 24 h. Significant reduction in serum blood urea nitrogen (BUN) and urea levels were observed even from 24 h post intervention irrespective of the treatments. LRF significantly improved acetate and decreased propionate production compared to SB. LRF at 7.5% (v/v) can thus be used to counteract ruminal fermentation disorders in goats sequel to high grain ration.

The safety and efficacy of balanced crystalloid vs. normal saline in non-cardiac surgeries - A systematic review and meta-analysis.

OBJECTIVE: Balanced crystalloid and normal saline are routinely used in clinical anesthesia, but their safety and efficacy in non-cardiac surgeries are still unclear. MATERIALS AND METHODS: PubMed, Embase, Web of Science, Cochrane Library, Wanfang, and CNKI, from January 1980 to March 2023, were searched. Studies comparing balanced crystalloid (BC) with normal saline (NS) during non-cardiac surgeries were included. The primary outcomes were clinical outcomes (acidosis, renal insufficiency, and mortality), and the secondary outcomes were pH value, Na+, Cl- and creatinine levels, and vasopressor requirement. RESULTS: Forty-three RCTs were included in this meta-analysis. Low evidence revealed that the development of acidosis was lower in the BC group than in the NS group (OR: 0.05, 95% CI: 0.01-0.43, I2=80.8%, p=0.00), and no between-group difference exists in renal insufficiency and mortality. At the end of surgery and on postoperative day 1 (POD 1), the pH value was higher, and the levels of Na+ and Cl- were lower in the BC group. No between-group difference exists in creatinine level and vasopressor requirement. CONCLUSIONS: Perioperative balanced crystalloids can maintain the stability of acid-base and electrolyte balance and reduce acidosis compared with saline, but they cannot reduce postoperative renal insufficiency and mortality.

Heterogeneous Sensor-Carrier Microswarms for Collaborative Precise Drug Delivery toward Unknown Targets with Localized Acidosis.

Micro/nanorobots hold the potential to revolutionize biomedicine by executing diverse tasks in hard-to-reach biological environments. Nevertheless, achieving precise drug delivery to unknown disease sites using swarming micro/nanorobots remains a significant challenge. Here we develop a heterogeneous swarm comprising sensing microrobots (sensor-bots) and drug-carrying microrobots (carrier-bots) with collaborative tasking capabilities for precise drug delivery toward unknown sites. Leveraging robust interspecific hydrodynamic interactions, the sensor-bots and carrier-bots spontaneously synchronize and self-organize into stable heterogeneous microswarms. Given that the sensor-bots can create real-time pH maps employing pH-responsive structural-color changes and the doxorubicin-loaded carrier-bots exhibit selective adhesion to acidic targets via pH-responsive charge reversal, the sensor-carrier microswarm, when exploring unknown environments, can detect and localize uncharted acidic targets, guide itself to cover the area, and finally deploy therapeutic carrier-bots precisely there. This versatile platform holds promise for treating diseases with localized acidosis and inspires future theranostic microsystems with expandability, task flexibility, and high efficiency.

Association Between Maternal Body Mass Index and Fetal Acidosis in Term Twin Pregnancies: A Retrospective Cohort Study.

OBJECTIVES: Given the increased risk of fetal acidosis in singleton neonates born to pregnant people with an elevated BMI, our objective was to evaluate the association between pre-pregnancy/first-trimester BMI and fetal acidosis among term twin pregnancies. METHODS: Retrospective study of pregnant people with twin gestation and their term infants admitted to our centre between 2014 and 2019. Using a generalized estimating equation, the association between maternal BMI and fetal acidosis was determined using odds ratios (ORs) with 95% CIs. A two-sided P < 0.05 was considered significant. RESULTS: A total of 275 pregnant people and 550 infants were analyzed. The number (%) of pregnancies in each BMI class were 10 (4%) underweight, 155 (56%) normal weight, 66 (24%) overweight, 22 (8%) class I, 9 (3%) class II, and 13 (5%) class III. The prevalence of maternal diabetes and hypertension was highest in class III (31%) and class II (44%), respectively. Fetal acidosis was diagnosed in 35 (6%) infants. After adjusting for confounders (maternal age, diabetes, and hypertension), infants born to those with elevated BMI did not have increased odds of fetal acidosis compared to those born to underweight and normal weight group (OR 1.29; 95% CI 0.38-4.41 for class I, P = 0.67 and OR 2.80; 95% CI 0.62-12.62 for the combined classes II and III, P = 0.18). CONCLUSIONS: Maternal BMI was not associated with fetal acidosis in term twin pregnancies. Further research is required to corroborate study findings due to small sample size.

Effects of pellet starch levels in automatic milking systems on rumen fermentation, plasma metabolites, and milk production in mid-lactation cows.

The aim of this study was to evaluate whether the starch levels in pellets fed to cows in automatic milking systems (AMS) affect subacute ruminal acidosis (SARA) occurrence and metabolite parameters. Twenty-four lactating cows (124.4 ± 49.9 days in milk) were studied in a crossover design with two periods of 21 days each and two treatment groups-a control group fed AMS pellets containing 30.0% of starch dry matter (DM) and an experimental group fed AMS pellets containing 23.5% of starch DM. All cows received the same partial mixed ration (PMR). The 1-hr mean ruminal pH in both groups decreased over 4 hr after feeding on PMR but recovered by the next morning. The ruminal pH was unaffected by either treatment, and both groups developed SARA. The groups had no significant differences in the concentrations of ruminal volatile fatty acids, lipopolysaccharides, plasma acute-phase proteins, other metabolites, and hormones. The milk yield and composition were not different in both groups. Feeding low-starch pellets in the AMS did not contribute to the risk of SARA occurrence in cows and had no additive effects on rumen fermentation, plasma metabolites, or milk production.

Analgesia to acidosis: metabolic acidosis due to chronic acetaminophen (paracetamol) use.

This case describes a rare occurrence of high anion gap metabolic acidosis due to chronic acetaminophen (paracetamol) usage, which can be confirmed by measuring 5-oxoproline (pyroglutamate), an organic acid metabolite. As acetaminophen is an extremely common drug prescribed in both inpatient and outpatient settings, a high degree of clinical suspicion is required to isolate it as the aetiology for metabolic acidosis. Management includes discontinuation of acetaminophen use and at times the supplementation of oral bicarbonate. Metabolic acidosis due to a high anion gap is commonly described by the mnemonic 'MUDPILES' in daily practice. A newer mnemonic, 'GOLD MARK' is proposed to be a more inclusive tool to assist in determining the cause of high anion gap metabolic acidosis, especially with such cases being reported.

Cullin-3 proteins be a novel biomarkers and therapeutic targets for hyperchloremia induced by oral poisoning.

Oral poisoning can trigger diverse physiological reactions, determined by the toxic substance involved. One such consequence is hyperchloremia, characterized by an elevated level of chloride in the blood and leads to kidney damage and impairing chloride ion regulation. Here, we conducted a comprehensive genome-wide analysis to investigate genes or proteins linked to hyperchloremia. Our analysis included functional enrichment, protein-protein interactions, gene expression, exploration of molecular pathways, and the identification of potential shared genetic factors contributing to the development of hyperchloremia. Functional enrichment analysis revealed that oral poisoning owing hyperchloremia is associated with 4 proteins e.g. Kelch-like protein 3, Serine/threonine-protein kinase WNK4, Serine/threonine-protein kinase WNK1 and Cullin-3. The protein-protein interaction network revealed Cullin-3 as an exceptional protein, displaying a maximum connection of 18 nodes. Insufficient data from transcriptomic analysis indicates that there are lack of information having direct associations between these proteins and human-related functions to oral poisoning, hyperchloremia, or metabolic acidosis. The metabolic pathway of Cullin-3 protein revealed that the derivative is Sulfonamide which play role in, increasing urine output, and metabolic acidosis resulted in hypertension. Based on molecular docking results analysis it found that Cullin-3 proteins has the lowest binding energies score and being suitable proteins. Moreover, no major variations were observed in unbound Cullin-3 and all three peptide bound complexes shows that all systems remain compact during 50 ns simulations. The results of our study revealed Cullin-3 proteins be a strong foundation for the development of potential drug targets or biomarker for future studies.