Serum Ratio Research Articles

High-precision K isotopic analysis of cerebrospinal fluid and blood serum microsamples via multicollector inductively coupled plasma-mass spectrometry equipped with 1013 Ω faraday cup amplifier resistors

BackgroundPotassium isotopic analysis is increasingly performed in both geological and biological contexts as a result of the introduction of MC-ICP-MS instrumentation either equipped with a collision/reaction cell or having the capability of working at “extra-high” mass resolution in order to deal with spectral interference caused by argon hydride (ArH+) ions. Potassium plays an important role in the central nervous system, and its isotopic analysis could provide an enhanced insight into the corresponding processes, but K isotopic analysis of cerebrospinal fluid is challenging due to the small volume, a few microliter only, typically available. This work aimed at developing a method for determining the K isotopic signature of serum and cerebrospinal fluid at a final K concentration of 25 ng mL−1 using Faraday cup amplifiers equipped with a 1013 Ω resistor. ResultsPotassium isotope ratios obtained for reference materials measured at a final K concentration of 25 ng mL−1 were in excellent agreement with the corresponding reference values and the internal and external precision for the δ41K value was 0.11 ‰ (2SE, N = 50) and 0.10 ‰ (2SD, N = 6), respectively. The robustness against the presence of matrix elements and the concentration mismatch between sample and standard observed at higher K concentrations is preserved at low K concentration. Finally, K isotopic analysis of serum and cerebrospinal fluid (3–12 μL of sample) of healthy mice of both sexes was performed, revealing a trend towards an isotopically lighter signature for serum and cerebrospinal fluid from female individuals, however being significant for serum only. SignificanceThis work provides a robust method for high-precision K isotopic analysis at a concentration of 25 ng mL−1. By monitoring both K isotopes, 39K and 41K, with Faraday cups connected to amplifiers with 1013 Ω resistors, accurate K isotope ratio results are obtained with a two-fold improvement in internal and external precision compared to those obtained with the set-up with traditional 1011 Ω resistors. The difference in the K isotope ratio in CSF and serum between the sexes, is possibly indicating an influence of the sex or hormones on the fractionation effects accompanying cellular uptake/release.

An-Gong-Niu-Huang-Wan (AGNHW) regulates cerebral blood flow by improving hypoperfusion, cerebrovascular reactivity and microcirculation disturbances after stroke

BackgroundThe restoration of cerebrovascular regulation and improvement of cerebral blood flow in ischaemic regions are crucial for improving the clinical prognosis after stroke. An-Gong-Niu-Huang-Wan (AGNHW) is a famous traditional compound Chinese medicine that has been used for over 220 years to treat acute ischaemic stroke; however, its role in the regulation of cerebral blood flow is still unclear. The aim of the present study was to investigate the regulatory effect of AGNHW on cerebral blood flow and microcirculation after ischaemic stroke and to elucidate the underlying mechanisms involved.MethodsMale C57BL/6 mice were subjected to distal middle cerebral artery occlusion (dMCAO) and randomly assigned to the sham, MCAO, or AGNHW groups. AGNHW was administered intragastrically 1 h after dMCAO. The rotarod test was utilized to evaluate behavioural function; TTC was used to determine the infarct volume; and ischaemic injury was assessed by detecting brain levels of SOD, MDA and NO. Then, cortical perfusion and acetazolamide-induced cerebrovascular reactivity were assessed using laser speckle contrast imaging, and the velocity and flux of red blood cells in cortical capillaries were detected using two-photon laser scanning microscopy. In addition, we employed RNA-Seq to identify variations in gene expression profiles and assessed endothelium-dependent changes in microcirculatory dysfunction by measuring vasoactive mediator levels.ResultsAGNHW significantly increased cerebral blood flow, reduced the infarct volume, and promoted functional recovery after cerebral ischaemia. AGNHW increased the velocity and flux of red blood cells in capillaries and improved cerebrovascular reactivity in the ischaemic cortex. Furthermore, AGNHW regulated endothelium-dependent microcirculation, as evidenced by decreases in the expression of endothelins (Edn1, Edn3 and Ednrb) and the ratios of brain and serum TXB2/6-keto-PGF1α and ET-1/CGRP.ConclusionsAGNHW improved cerebral hypoperfusion, regulated cerebrovascular reactivity and attenuated microcirculatory dysfunction within the ischaemic cortex after stroke. This outstanding effect was achieved by modulating the expression of genes related to vascular endothelial cell function and regulating endothelium-dependent vasoactive mediators.

Serum NfL and EGFR/NfL ratio mRNAs as biomarkers for phenotype and disease severity of myelin oligodendrocyte glycoprotein IgG-associated disease.

Myelin oligodendrocyte glycoprotein (MOG) IgG is frequently elevated in pediatric patients with acquired demyelinating syndrome (ADS). However, no specific biomarkers exist for phenotype classification, symptom severity, prognosis, and treatment guidance of MOG-IgG-associated disease (MOGAD). This study evaluated neurofilament light chain (NfL) and endothelial growth factor receptor (EGFR) mRNA expression levels in serum and cerebrospinal fluid (CSF) as potential biomarkers for MOGAD in Chinese children. This was a cross-sectional and single-center study. We enrolled 22 consecutive pediatric patients hospitalized with MOGAD and 20 control pediatric patients hospitalized for noninflammatory neurological diseases in Hebei Children's Hospital. Serum and CSF were collected from MOGAD patients within 3 days before immunotherapy. The mRNA levels of NfL and EGFR in serum and CSF were measured by real-time polymerase chain reaction (qPCR), and the EGFR/NfL ratio mRNA was calculated. These measurement values were then compared between disease groups and among MOGAD phenotypes. In addition, the correlations between the mRNAs of three markers (NfL, EGFR, EGFR/NfL ratio), extended disability status scale (EDSS) scores, and clinical phenotypes were analyzed. Serum and CSF NfL mRNA levels were significantly higher of acute-stage MOGAD patients than those of control patients (p< 0.05 and p< 0.01, respectively), while the mRNA levels of serum EGFR and EGFR/NfL ratio were significantly lower of MOGAD patients than those of controls (p < 0.05, p < 0.0001). Serum NfL mRNA was significantly correlated with mRNA of serum EGFR (r =0.480, p < 0.05). Serum and CSF NfL mRNA levels in MOGAD patients with the ADEM-like phenotype were also significantly higher than those in control patients (p < 0.01, p < 0.01) and optic neuritis (ON) phenotype (p < 0.05, p < 0.05). Both mRNAs of NfL in CSF and EGFR/NfL ratio in serum were correlated with EDSS scores (p < 0.05, r = 0.424; p < 0.05, r= -0.521). The mRNA levels of elevated NfL in serum and CSF as well as lower EGFR and EGFR/NfL ratio in serum could help distinguish acute-phase MOGAD. Higher mRNA levels of NfL in serum and CSF of MOGAD patients help distinguish ADEM-like phenotype. In addition, serum EGFR/NfL mRNA ratio is indicative ofdisease severity in pediatric patients with MOGAD. Further investigations arewarranted to elucidate the pathological mechanisms underlying these associations.

Association of circulation very long chain saturated fatty acids with depression in NHANES 2011–2014

BackgroundRecent studies have shown that elevated levels of medium and long chain saturated fatty acids are associated with an increased risk of depression. However, little is known about the effect of very long chain saturated fatty acids (VLSFAs) on depression. Therefore, our study aimed to examine the association between VLSFAs and depression in the US adult population. MethodsA total of 2706 participants with serum VLSFAs detection from NHANES 2011–2014 were included in the study. Logistic regression models were used to evaluate the association between quartile levels of serum VLSFAs (20:0, 22:0, 23:0, 24:0, and total VLSFA) and depression. ResultsAfter adjusting for multiple variables, we found that increased circulating levels of 22:0, 23:0, 24:0 and total VLSFA were linearly associated with a reduced risk of depression (model 3, Q4 OR: 0.658, 95 % CI: 0.438–0.989, P-trend = 0.023; OR: 0.515, 95 % CI: 0.339–0.782, P-trend<0.001; OR: 0.556, 95 % CI: 0.370–0.835, P-trend = 0.003; OR: 0.652, 95 % CI: 0.435–0.976, P-trend = 0.021, respectively). Additionally, individuals with the highest serum ratios of 22:0/16:0, 23:0/16:0, 24:0/16:0 and total VLSFA/16:0 also had a lower risk of depression after adjusting for multiple variables compared to the group with the lowest serum VLSFAs/16:0 (P-trend = 0.001, <0.001, 0.001 and 0.004, respectively). Moreover, the decreasing trend of depression associated with increased VLSFAs/18:0 remained significant. ConclusionIn conclusion, our findings suggest that increased circulating levels of 22:0, 23:0, 24:0 and total VLSFA may have a protective effect against the risk of depression.

Blood Urea Nitrogen-Serum Albumin Ratio As a Predictor of Clinical Outcome in Acute Ischemic Stroke

Stroke is a global health issue with high morbidity and fatality rates. Treatment decisions for ischemic stroke rely on clinical outcome prediction. The NIHSS score is commonly used to predict the AIS's clinical outcomes. However, its use is hindered by its complexity, which requires the assessment of many variables. Therefore, there is an urgent need to develop a simpler yet still effective evaluation tool in assessing the AIS’s clinical outcome. The study aimed to predict AIS outcomes using the blood urea nitrogen to albumin serum ratio (RBA). This study was a prospective cohort study design, with subjects being first-time AIS patients hospitalized at RSUP Dr. Wahidin Sudirohusodo and several hospitals in Makassar from December 2022–April 2023. Demographic and clinical data were collected, assessing RBA and comparing it according to the good (mRS 0-2) and poor (mRS 3-6) outcome groups. RBA performance was assessed by receiver operating characteristic curve (ROC) analysis to assess the AIS's clinical outcome. The study's findings on 62 participants meeting the criteria revealed a significant association between RBA and the AIS's clinical outcome (p-value=0,0004). The mean RBA differed significantly between the good and poor AIS outcome groups (p-value =0,006). In the ROC analysis, the area under the curve (AUC) was 0,75 with an optimal cut-off value was 2,05, yielding a sensitivity of 41,67%, a specificity of 98%, and a likelihood ratio of 20,83 (p-value=0,007). In conclusion, RBA can be used as a simple and objective tool to determine the clinical outcome predictors of AIS.

The Effect of an Elevated Dietary Copper Level on the Vascular Contractility and Oxidative Stress in Middle-Aged Rats.

Copper (Cu), being an essential mineral, plays a crucial role in maintaining physiological homeostasis across multiple bodily systems, notably the cardiovascular system. However, an increased Cu level in the body may cause blood vessel dysfunction and oxidative stress, which is unfavorable for the cardiovascular system. Middle-aged (7-8 months old) male Wistar rats (n/group = 12) received a diet supplemented with 6.45 mg Cu/kg (100% of the recommended daily dietary quantity of copper) for 8 weeks (Group A). The experimental group received 12.9 mg Cu/kg of diet (200%-Group B). An ex vivo study revealed that supplementation with 200% Cu decreased the contraction of isolated aortic rings to noradrenaline (0.7-fold) through FP receptor modulation. Vasodilation to sodium nitroprusside (1.10-fold) and acetylcholine (1.13-fold) was potentiated due to the increased net effect of prostacyclin derived from cyclooxygenase-1. Nitric oxide (NO, 2.08-fold), superoxide anion (O2•-, 1.5-fold), and hydrogen peroxide (H2O2, 2.33-fold) measured in the aortic rings increased. Blood serum antioxidant status (TAS, 1.6-fold), Cu (1.2-fold), Zn (1.1-fold), and the Cu/Zn ratio (1.4-fold) increased. An increase in Cu (1.12-fold) and the Cu/Zn ratio (1.09-fold) was also seen in the rats' livers. Meanwhile, cyclooxygenase-1 (0.7-fold), cyclooxygenase-2 (0.4-fold) and glyceraldehyde 3-phosphate dehydrogenase (0.5-fold) decreased. Moreover, a negative correlation between Cu and Zn was found (r = -0.80) in rat serum. Supplementation with 200% Cu did not modify the isolated heart functioning. No significant difference was found in the body weight, fat/lean body ratio, and organ weight for either the heart or liver, spleen, kidney, and brain. Neither Fe nor Se, the Cu/Se ratio, the Se/Zn ratio (in serum and liver), heme oxygenase-1 (HO-1), endothelial nitric oxide synthase (eNOS), or intercellular adhesion molecule-1 (iCAM-1) (in serum) were modified. Supplementation with 200% of Cu potentiated pro-oxidant status and modified vascular contractility in middle-aged rats.

Comparison of serum and salivary creatinine levels in preterm neonates

&lt;b&gt;Introduction:&lt;/b&gt; In recent years, saliva has been frequently tested as an alternative biological sample for diagnosing various diseases. Various substances reach the saliva through endogenous synthesis in acinar cells or from plasma. Passive diffusion, transudation, diffusion, or selective transport are how these substances cross from plasma to saliva. There are a small number of studies in children and adults that have examined renal function and the ratio of serum and salivary creatinine. To date, no study has been conducted that examined the existence of this correlation in neonates. Our study aimed to examine whether there is a correlation between serum and salivary creatinine values in preterm infants.&lt;br /&gt; &lt;b&gt;Methods:&lt;/b&gt; We conducted a prospective study that included 30 neonates, in whom serum and salivary creatinine levels were measured simultaneously in two-time spots.&lt;br /&gt; &lt;b&gt;Results:&lt;/b&gt; The mean value of salivary to serum creatinine (sCr) ratio was 0.700. Salivary to sCr ratio was statistically significantly higher in newborns of gestational age (GA)&amp;lt;28 gestational weeks (mean value 0.825), compared to children with GA≥28 gestational weeks (mean value 0.566), student t-test; p=0.003. Logistic regression showed that the correlation between serum and salivary creatinine levels was more coherent in newborns with GA&amp;lt;28 weeks.&lt;br /&gt; &lt;b&gt;Conclusions:&lt;/b&gt; In this study, it was examined for the first time whether there is a correlation between the values of serum and salivary creatinine in preterm infants. We found that the correlation between serum and salivary creatinine levels is strong in newborns with GA&amp;lt;28 weeks.

Evaluation of Artemisia dubia folium extract-mediated immune efficacy through developing a murine model for acute and chronic stages of atopic dermatitis

BackgroundAtopic dermatitis (AD) is a biphasic type of skin inflammation characterized by a predominance of type-2 (TH2) and type-1 (TH1) helper T cell-biased immune responses at the acute and persistent chronic phases, respectively. The present study was aimed to evaluate the efficacy of Artemisia dubia folium extract (ADFE) on AD-like skin lesions through developing a murine model for acute and chronic stages of AD. To induce acute phase AD, the dorsal skin of BALB/c mice was sensitized twice a week with 1% 2, 4-dinitrochlorobenzene (DNCB), followed by challenge (twice) in the following week with 0.2% DNCB. To induce persistent chronic AD, some mice were challenged twice a week for 4 more weeks. After the second challenge, the dorsal skin was exposed to 3% ADFE (five times per week) for 2 weeks (acute phase) or 4 weeks (persistent chronic phase).ResultsThe paradigm of TH2 or TH1 predominance at the acute and chronic phase, respectively, was observed in this mouse model. During the acute phase, we observed an increased IL-4/IFN-γ ratio in splenic culture supernatants, an increased IgG1/IgG2a ratio in serum, and elevated serum IgE levels; however, the skew toward TH2 responses was diminished during the chronic stage. Compared with vehicle controls, ADFE reduced the IL-4/IFN-γ and IgG1/IgG2a ratios in acute AD, but both ratios increased during the chronic stage.ConclusionsOur results suggest that ADFE concomitantly suppresses the TH2 predominant response in acute AD, as well as the TH1 predominant response in chronic AD. Thus, ADFE is a candidate therapeutic for AD.

Development rat models of nephrotoxic: A pre-clinical test model to discover nephroprotective agents

Background: The use of drugs, including aminoglycoside drugs and anticancer drugs, is one of the things that can cause toxicity to the kidneys. Therefore, the development of agents that function as nephroprotectors continues to be researched. Objective: This study aims to obtain a nephrotoxic experimental animal model for testing nephroprotective agents. Method: The treatment was normal group, groups given a single dose of Cisplatin 7 mg/kgBW i.p (Cis), Doxorubicin single dose 25 mg/kgBW i.p (Dox-25), Doxorubicin repeated dose 4 mg/kgBW i.p twice/week for two weeks (Dox-4 repeated dose), and Gentamicin single dose 112 mg/kgBW i.p (Gen). The nephrotoxic effect was assessed by the parameters of kidney weight ratio, Ureum, Creatinine and Albumin levels in rat serum. Result: The nephrotoxic effect was indicated by an increase in the renal weight ratio of the Cisplatin; Dox-25, Dox-4 repeated, and Gen groups than normal, respectively. There was an increase in serum BUN levels, an increase in serum creatinine, and a decrease in serum albumin levels compared to the normal group. Conclusion: Cisplatin, Doxorubicin and Gentamicin have nephrotoxic effects. The administration of a single dose of cisplatin at 7 mg/kg BW gave the strongest nephrotoxic effect, making it appropriate as a model of acute nephrotoxicity in rats.

Диагностическое значение определения IgG4 сыворотки в дифференциальной диагностике склерозирующих холангитов

The aim: to determine the cut-off levels of serum IgG. IgG4 and IgG4/IgG ratio for the differential diagnosis of IgG4-sclerosing cholangitis and primary sclerosing cholangitis. Material and methods. We conducted a single-center study of 32 and 67 patients with IgG4-sclerosing cholangitis and primary sclerosing cholangitis. which were verified according to HISORt and EASL criteria. respectively. Patients underwent determination of total IgG and IgG4 in serum by enzyme immunoassay. and the IgG4/IgG ratio was calculated before the initiation of glucocorticoid therapy. The reference values for IgG were 7–16 g/L and for IgG4 ≤ 1.35 g/L. ROC-analysis was used to determine the cut-off values of serum IgG. IgG4. IgG4/IgG ratio for differential diagnosis between primary sclerosing cholangitis and IgG4-sclerosing cholangitis. Results. The mean age at diagnosis of IgG4-sclerosing cholangitis was 59 ± 13 years and primary sclerosing cholangitis was 41 ± 20 years (p &lt; 0.001). IgG4-sclerosing cholangitis was initially misdiagnosed as primary sclerosing cholangitis in 41.2% of patients (95% CI 24.6–59.3). The median time before diagnosis of IgG4-sclerosing cholangitis was 10.5 months. The median serum IgG4 level was 2.7 g/L [1.92; 6.48] in patients with IgG4-sclerosing cholangitis and 0.6 g/L [0.60; 1.45] in patients with primary sclerosing cholangitis. 33% of patients with primary sclerosing cholangitis had blood IgG4 levels exceeded 1.35 g/L. Whereas among patients with IgG4-sclerosing cholangitis. 19.4% had normal values of this parameter. The cut-off values of serum IgG and IgG4 and IgG4/IgG ratios for distinguishing primary sclerosing cholangitis from IgG4-sclerosing cholangitis were 17.1 g/L (sensitivity 75.0% and specificity 72.4%). 1.99 g/L (sensitivity 92.3% and specificity 74.2%). and 0.11 (sensitivity 84.2% and specificity 64.3%). respectively. Conclusions. The cut-off values of IgG. IgG4 concentration and IgG4/IgG ratio in serum can be used for differential diagnosis of primary sclerosing cholangitis and IgG4-sclerosing cholangitis.

Angiogenic imbalance in pregnancies with preterm prelabor rupture of membranes between 34 and 37 weeks of gestation.

This study aimed to identify whether microbial invasion of the amniotic cavity and/or intra-amniotic inflammation in women with late preterm prelabor rupture of membranes (PPROM) was associated with changes in concentrations of soluble fms-like tyrosine kinase-1 (sFlt-1), placental growth factor (PlGF) and its ratio in maternal serum, and whether placental features consistent with maternal vascular malperfusion further affect their concentrations. This historical study included 154 women with singleton pregnancies complicated by PPROM between gestational ages 34+0 and 36+6 weeks. Transabdominal amniocentesis was performed as part of standard clinical management to evaluate the intra-amniotic environment. Women were categorized into two subgroups based on the presence of microorganisms and/or their nucleic acids in amniotic fluid (determined by culturing and molecular biology method) and intra-amniotic inflammation (by amniotic fluid interleukin-6 concentration evaluation): (1) those with the presence of microorganisms and/or inflammation (at least one present) and (2) those with negative amniotic fluid for infection/inflammation (absence of both). Concentrations of sFlt-1 and PlGF were assessed using the Elecsys® sFlt-1 and Elecsys® PlGF immunoassays and converted into multiples of medians. Women with the presence of microorganisms and/or inflammation in amniotic fluid had lower serum concentrations of sFlt-1 and sFlt-1/PlGF ratios and higher concentrations of PlGF compared with those with negative amniotic fluid. (sFlt-1: presence: median 1.0 multiples of the median (MoM), vs negative: median: 1.5 MoM, P = 0.003; PlGF: presence: median 0.7 MoM, vs negative: median 0.4 MoM, P = 0.02; sFlt-1/PlGF: presence: median 8.9 vs negative 25.0, P = 0.001). Higher serum concentrations of sFlt-1 and sFlt-1/PlGF ratios as well as lower concentrations of PlGF were found in the subsets of women with maternal vascular malperfusion than in those without maternal vascular malperfusion. Among women experiencing late PPROM, angiogenic imbalance in maternal serum is primarily observed in those without both microbial invasion of the amniotic cavity and intra-amniotic inflammation. Additionally, there is an association between angiogenic imbalance and the presence of maternal vascular malperfusion.

Potential Mechanisms of Casein Hexapeptide YPVEPF on Stress-Induced Anxiety and Insomnia Mice and Its Molecular Effects and Key Active Structure.

The hexapeptide YPVEPF with strong sleep-enhancing effects could be detected in rat brain after a single oral administration as we previously proved. In this study, the mechanism and molecular effects of YPVEPF in the targeted stress-induced anxiety mice were first investigated, and its key active structure was further explored. The results showed that YPVEPF could significantly prolong sleep duration and improve the anxiety indexes, including prolonging the time spent in the open arms and in the center. Meanwhile, YPVEPF showed strong sleep-enhancing effects by significantly increasing the level of the GABA/Glu ratio, 5-HT, and dopamine in brain and serum and regulating the anabolism of multiple targets, but the effects could be blocked by bicuculline and WAY100135. Moreover, the molecular simulation results showed that YPVEPF could stably bind to the vital GABAA and 5-HT1A receptors due to the vital structure of Tyr-Pro-Xaa-Xaa-Pro-, and the electrostatic and van der Waals energy played dominant roles in stabilizing the conformation. Therefore, YPVEPF displayed sleep-enhancing and anxiolytic effects by regulating the GABA-Glu metabolic pathway and serotoninergic system depending on distinctive self-folding structures with Tyr and two Pro repeats.

Evaluating serum CXCL12, sCD22, Lp-PLA2 levels and ratios as biomarkers for diagnosis of Alzheimer's disease.

Grasping the underlying mechanisms of Alzheimer's disease (AD) is still a work in progress, and existing diagnostic techniques encounter various obstacles. Therefore, the discovery of dependable biomarkers is essential for early detection, tracking the disease's advancement, and steering treatment strategies. To explore the diagnostic potential of serum CXCL12, sCD22, Lp-PLA2, and their ratios in AD, aiming to enhance early detection and inform targeted treatment strategies. The study was conducted in Dongying people's Hospital from January 2021 to December 2022. Participants included 60 AD patients (AD group) and 60 healthy people (control group). Using a prospective case-control design, the levels of CXCL12, sCD22 and Lp-PLA2 and their ratios were detected by enzyme-linked immunosorbent assay kit in the diagnosis of AD. The differences between the two groups were analyzed by statistical methods, and the corresponding ratio was constructed to improve the specificity and sensitivity of diagnosis. Serum CXCL12 levels were higher in the AD group (47.2 ± 8.5 ng/mL) than the control group (32.8 ± 5.7 ng/mL, P < 0.001), while sCD22 levels were lower (14.3 ± 2.1 ng/mL vs 18.9 ± 3.4 ng/mL, P < 0.01). Lp-PLA2 levels were also higher in the AD group (112.5 ± 20.6 ng/mL vs 89.7 ± 15.2 ng/mL, P < 0.05). Significant differences were noted in CXCL12/sCD22 (3.3 vs 1.7, P < 0.001) and Lp-PLA2/sCD22 ratios (8.0 vs 5.2, P < 0.05) between the groups. Receiver operating characteristic analysis confirmed high sensitivity and specificity of these markers and their ratios in distinguishing AD, with area under the curves ranging from 0.568 to 0.787. Serum CXCL12 and Lp-PLA2 levels were significantly increased, while sCD22 were significantly decreased, as well as increases in the ratios of CXCL12/sCD22 and Lp-PLA2/sCD22, are closely related to the onset of AD. These biomarkers and their ratios can be used as potential diagnostic indicators for AD, providing an important clinical reference for early intervention and treatment.

Mitochondrial DNA deletions in the cerebrospinal fluid of patients with idiopathic REM sleep behaviour disorder

Idiopathic rapid eye movement (REM) sleep behaviour disorder (IRBD) represents the prodromal stage of Lewy body disorders (Parkinson's disease (PD) and dementia with Lewy bodies (DLB)) which are linked to variations in circulating cell-free mitochondrial DNA (cf-mtDNA). Here, we assessed whether altered cf-mtDNA release and integrity are already present in IRBD. We used multiplex digital PCR (dPCR) to quantify cf-mtDNA copies and deletion ratio in cerebrospinal fluid (CSF) and serum in a cohort of 71 participants, including 1) 17 patients with IRBD who remained disease-free (non-converters), 2) 34 patients initially diagnosed with IRBD who later developed either PD or DLB (converters), and 3) 20 age-matched controls without IRBD or Parkinsonism. In addition, we investigated whether CD9-positive extracellular vesicles (CD9-EVs) from CSF and serum samples contained cf-mtDNA. Patients with IRBD, both converters and non-converters, exhibited more cf-mtDNA with deletions in the CSF than controls. This finding was confirmed in CD9-EVs. The high levels of deleted cf-mtDNA in CSF corresponded to a significant decrease in cf-mtDNA copies in CD9-EVs in both IRBD non-converters and converters. Conversely, a significant increase in cf-mtDNA copies was found in serum and CD9-EVs from the serum of patients with IRBD who later converted to a Lewy body disorder. Alterations in cf-mtDNA copy number and deletion ratio known to occur in Lewy body disorders are already present in IRBD and are not a consequence of Lewy body disease conversion. This suggests that mtDNA dysfunction is a primary molecular mechanism of the pathophysiological cascade that precedes the full clinical motor and cognitive manifestation of Lewy body disorders. Funded by Michael J. Fox Foundation research grant MJFF-001111. Funded by MICIU/AEI/10.13039/501100011033 "ERDF A way of making Europe", grants PID2020-115091RB-I00 (RT) and PID2022-143279OB-I00 (ACo). Funded by Instituto de Salud Carlos III and European Union NextGenerationEU/PRTR, grant PMP22/00100 (RT and ACo). Funded by AGAUR/Generalitat de Catalunya, grant SGR00490 (RT and ACo). MP has an FPI fellowship, PRE2018-083297, funded by MICIU/AEI/10.13039/501100011033 "ESF Investing in your future".

Therapeutic potential of caffeic acid and coumarin in modifying aluminum-induced hepatic injury in Wistar rats

Antioxidants and phenolic compounds have always been tested as chemoprotective agents to regulate disease progression related to oxidative stress. Through this study, we investigate the possible corrective effects of caffeic acid and coumarin against aluminum- (Al-) induced stress response and liver damage in rats. Male Wistar rats were divided into four groups (10 rats per group), cotreated with caffeic acid (30 mg kg-1) and coumarin (5 mg kg-1) and exposed to aluminum (60 mg kg-1) for 45 days. Al induced significant alterations in body and liver weight over time. It also led to a marked increase in plasma levels of transaminases (aspartate aminotransferase and alanine aminotransferase), alkaline phosphatase, and lactate dehydrogenase. Additionally, there was a substantial change in the lipid profile, characterized by elevated levels of triglycerides and total cholesterol in both serum and liver. Furthermore, the LDL-c level and the HDL-c/total cholesterol ratio in serum were also affected. In contrast, the levels of HDL-c in serum and phospholipids in liver tissues were reduced. The results of this study also showed increased levels of TBARS, protein carbonyls, nitrates/nitrites, and TNF-α. Conversely, the activity of antioxidant enzymes (catalase, GP-x, and SOD) was reduced. These altered parameters were restored after treating rats with caffeic acid and coumarin. Our study strongly suggests that caffeic acid and coumarin possess antioxidant properties and hepatoprotective capacity by attenuating aluminum toxicity-induced liver damage.

Red Blood Cell Adenylate Energetics Is Related to Endothelial and Microvascular Function in Long COVID.

Adenine nucleotides play a critical role in maintaining essential functions of red blood cells (RBCs), including energy metabolism, redox status, shape fluctuations and RBC-dependent endothelial and microvascular functions. Recently, it has been shown that infection with the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) might lead to morphological and metabolic alterations in erythrocytes in both mild and severe cases of coronavirus disease (COVID-19). However, little is known about the effects of COVID-19 on the nucleotide energetics of RBCs nor about the potential contribution of nucleotide metabolism to the long COVID syndrome. This study aimed to analyze the levels of adenine nucleotides in RBCs isolated from patients 12 weeks after mild SARS-CoV-2 infection who suffered from long COVID symptoms and to relate them with the endothelial and microvascular function parameters as well as the rate of peripheral tissue oxygen supply. Although the absolute quantities of adenine nucleotides in RBCs were rather slightly changed in long COVID individuals, many parameters related to the endothelial and microcirculatory function showed significant correlations with RBC adenosine triphosphate (ATP) and total adenine nucleotide (TAN) concentration. A particularly strong relationship was observed between ATP in RBCs and the serum ratio of arginine to asymmetric dimethylarginine-an indicator of endothelial function. Consistently, a positive correlation was also observed between the ATP/ADP ratio and diminished reactive hyperemic response in long COVID patients, assessed by the flow-mediated skin fluorescence (FMSF) technique, which reflected decreased vascular nitric oxide bioavailability. In addition, we have shown that patients after COVID-19 have significantly impaired ischemic response parameters (IR max and IR index), examined by FMSF, which revealed diminished residual bioavailability of oxygen in epidermal keratinocytes after brachial artery occlusion. These ischemic response parameters revealed a strong positive correlation with the RBC ATP/ADP ratio, confirming a key role of RBC bioenergetics in peripheral tissue oxygen supply. Taken together, the outcomes of this study indicate that dysregulation of metabolic processes in erythrocytes with the co-occurring endothelial and microvascular dysfunction is associated with diminished intracellular oxygen delivery, which may partly explain long COVID-specific symptoms such as physical impairment and fatigue.

Pteridine and tryptophan pathways in children with type 1 diabetes: Isoxanthopterin as an indicator of endothelial dysfunction

AimType 1 diabetes (T1D) and its complications are known to be associated with oxidative stress. Pteridine derivatives and indoleamine 2,3-dioxygenase (IDO) activity can be used as biomarkers in the evaluation of oxidative stress. In this study, our aim is to compare the concentrations of serum and urinary pteridine derivatives, as well as serum IDO activity, in children and adolescents diagnosed with T1D and those in a healthy control group. MethodA cross-sectional study was performed and included 93 patients with T1D and 71 healthy children. Serum and urine biopterin, neopterin, monapterin, pterin, isoxanthopterin, and pterin-6-carboxylic acid (6PTC) and serum tryptophan and kynurenine levels were analyzed and compared with healthy controls. High-performance liquid chromatography was used for the analysis of pteridine derivatives, tryptophan, and kynurenine. Xanthine oxidase (XO) activity, a marker of oxidative stress, was defined by measurement of serum and urine isoxanthopterin. As an indicator of indolamine 2,3-dioxygenase (IDO) activity, the ratio of serum kynurenine/tryptophan was used. ResultsSerum isoxanthopterin and tryptophan concentrations were increased, and serum 6PTC concentration was decreased in children with T1D (p=0.01, p=0.021, p<0.001, respectively). In children with T1D, IDO activity was not different from healthy controls (p>0.05). Serum neopterin level and duration of diabetes were weakly correlated (p=0.045, r=0.209); urine neopterin/creatinine and isoxanthopterin/creatinine levels were weakly correlated with HbA1c levels (p=0.005, r=0.305; p=0.021, r=0.249, respectively). Urine pterin/creatinine level negatively correlated with body mass index-SDS. (p=0.015, r=-0.208). ConclusionWe found for the first time that isoxanthopterin levels increased and 6PTC levels decreased in children and adolescents with T1D. Elevated isoxanthopterin levels suggest that the XO activity is increased in TID. Increased XO activity may be an indicator of vascular complications reflecting T1D-related endothelial dysfunction.

Distribution of quetiapine between serum and whole blood in therapeutic drug-monitoring specimens.

Quetiapine use is on the rise, leading to a corresponding increase in acute intoxications, some of which have fatal outcomes. When assessing whole-blood quetiapine concentrations during forensic autopsies, interpretations are primarily based on toxicity data from studies of serum concentrations. To our knowledge, there are only two previous studies that have attempted to establish the ratio between whole blood and serum quetiapine concentrations with limited populations and high variability of results. Paired specimens of whole blood and serum from 16 quetiapine users recruited from the Psychiatric Clinic, St. Olav University Hospital were analyzed using LC-MS-MS. Quetiapine concentrations in both matrices were determined and compared. The mean blood:serum ratio of quetiapine was 0.74 (standard deviation (SD) = 0.05, 95% confidence interval (CI) 0.71-0.76, P < 0.001), range 0.66-0.85. Simple linear regression showed strong linear correlation between quetiapine concentrations in the two matrices (B = 0.774, P > 0.001, r = 0.999). Our results imply that quetiapine occurs at lower concentrations within erythrocytes than in plasma. This is most likely due to a high degree of plasma protein binding. Other factors which may influence the distribution of quetiapine between these compartments are solubility, metabolism and passive or active efflux mechanisms. We did not observe any covariation between blood:serum ratios and serum concentrations. Quetiapine was consistently present at lower concentrations in whole blood than in serum. If so inclined to, a conversion factor of ∼0.7 may be considered for extrapolation of concentrations from serum to whole blood, at least in cases with therapeutic quetiapine concentration levels.

Parameters of oxidative, nitrasive and anti-oxidative status in men with erectile dys-function due to combat trauma

The development of oxidative and nitrative stress and the processes of free radical oxidation are associated with many pathological processes. Damage of any origin leads to the activation of free radical processes not only in the place of damage, but also in the whole organism. The aim of the study is to assess the state of lipid peroxidation, content of GSH and GSSG and the activity of NO-synthase and arginase in lymphocytes and peripheral blood serum in men with erectile dysfunction due to combat trauma. The research was conducted on peripheral blood lymphocytes of men injured as a result of combat operations (shrapnel and bullet wounds) in the Russian-Ukrainian war, and who were treated at the Military Medical Clinical Center of the Western Region (Lviv, Ukraine). The research group of men with combat injuries was divided into two age groups: men aged 20–39 years and men aged 40–53 years. The MDA content in the blood serum of patients of both age groups was 1.35 times higher than in the control group. In peripheral blood lymphocytes, the MDA content in patients of the young age group was 1.27, and in patients of the middle age group in 1.39 times higher than in the control group. Simultaneously, no significant changes in the concentration of oxidized glutathione in blood serum and blood lymphocytes were found between men with erectile dysfunction due to combat trauma and healthy men. GSH content in blood serum in patients of both age groups was significantly lower than in the control group. The arginase/NOS ratio in blood serum was 9.75 times lower in the young age group and in 20.45 times lower in the middle age group compared to healthy men. It was established that in the blood serum and blood lymphocytes of men with erectile dysfunction due to combat trauma, processes of lipid peroxidation were intensified and the GSH level was reduced. The GSH/GSSG ratio was reduced only in blood serum. It was found that the oxidative stress is associated with development of nitrative stress. The arginase/NOS ratio was shifted towards increased NOS activity. Activation of iNOS was accompanied by significant inhibition of cNOS. Further study of biochemical mechanisms is important to understand the triggers of erectile dysfunction due to combat trauma.

High Bile Titer and High Bile to Serum Ratio of CYFRA 21 - 1 Reliably Discriminate Malignant Biliary Obstruction Caused by Cholangiocarcinoma.

Previously we demonstrated that elevated serum CYFRA 21 - 1 is a reliable diagnostic and prognostic biomarker for biliary tract cancers. This study aims to explore the diagnostic performance of bile CYFRA 21 - 1 (bCYFRA 21 - 1) in discriminating malignant biliary obstruction (MBO) caused by cholangiocarcinoma (CCA). 77 CCA patients ((17 intrahepatic CCA (iCCA), 49 perihilar CCA (pCCA) and 11 distal CCA (dCCA)) and 43 benign patients with biliary obstruction were enrolled. Serum and bile levels of CYFRA 21 - 1, carcinoembryonic antigen (CEA) and carbohydrate antigen 19 - 9 (CA19-9) were quantified. Diagnostic performances of these biomarkers were estimated by receiver operator characteristic curves. Subgroups analysis of these tumor markers among CCA subtypes was performed. High bCYFRA 21 - 1 (cut-off value of 59.25 ng/mL with sensitivity of 0.889 and specificity of 0.750) and high bile to serum ratio of CYFRA 21 - 1 (b/sCYFRA 21 - 1, cut-off value of 31.55 with sensitivity of 0.741 and specificity of 0.778) achieved better diagnostic performance than any other biomarker in discriminating MBO. Subgroup analysis revealed that bCYFRA 21 - 1 was significantly elevated in all CCA subtypes; moreover b/sCYFRA 21 - 1 was upregulated in pCCA and dCCA (the mean b/sCYFRA 21 - 1 of pCCA was highest among CCA subtypes: 57.90, IQR 29.82-112.27). Both high biliary CYFRA 21 - 1 and high bile to serum ratio of CYFRA 21 - 1 were reliable diagnostic biomarkers for MBO caused by CCA.