Preoperative blood markers and intra-abdominal infection after colorectal cancer resection

BACKGROUND

Colorectal cancer (CRC) has one of the highest morbidity and mortality rates among digestive tract tumors. Intra-abdominal infection (IAI) is a common postoperative complication that affects the clinical outcomes of patients with CRC and hinders their rehabilitation process. However, the factors influencing abdominal infection after CRC surgery remain unclear; further, prediction models are rarely used to analyze preoperative laboratory indicators and postoperative complications.

AIM

To explore the predictive value of preoperative blood markers for IAI after radical resection of CRC.

METHODS

The data of 80 patients who underwent radical resection of CRC in the Anorectal Surgery Department of Suzhou Hospital affiliated with Anhui Medical University were analyzed. These patients were categorized into IAI (n = 15) and non-IAI groups (n = 65) based on whether IAI occurred. Influencing factors were compared; general data and laboratory indices of both groups were identified. The relationship between the indicators was assessed. Further, a nomogram prediction model was developed and evaluated; its utility and clinical applicability were assessed.

RESULTS

The risk factors for IAI after radical resection of CRC were neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), and carcinoembryonic antigen (CEA) levels. NLR was correlated with PLR and SII (r = 0.604, 0.925, and 0.305, respectively), while PLR was correlated with SII (r = 0.787). The nomogram prediction model demonstrated an area under the curve of 0.968 [95% confidence interval (CI): 0.948-0.988] in the training set (n = 60) and 0.926 (95%CI: 0.906-0.980) in the validation set (n = 20). The average absolute errors of the calibration curves for the training and validation sets were 0.032 and 0.048, respectively, indicating a good model fit. The decision curve analysis curves demonstrated high net income above the 5% threshold, indicating the clinical practicality of the model.

CONCLUSION

The nomogram model constructed using NLR, PLR, SII, and CEA levels had good accuracy and reliability in predicting IAI after radical resection of CRC, potentially aiding clinical treatment decision-making.

Preoperative lymphocyte count, neutrophil to lymphocyte and platelet to lymphocyte ratio predict the recurrence with progression and cancerization in vocal fold lesions-retrospective study

Backgrounds

This study explored the contribution of peripheral blood markers in diagnosis and prognosis estimation of different stages of laryngeal dysplasia and early glottic cancer.

Methods

Retrospective analysis of clinical, histopathological and laboratory data of 220 patients including hemoglobin, neutrophil, lymphocyte, monocyte and platelet counts, neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR).

Results

The mean hemoglobin level and platelets count showed differences between histopathological stages of lesions (p = 0.041 and 0.046, respectively). In patients with recurrent lesions mean level of lymphocyte count, NLR and PLR were significant in assessing progression and cancerization (p = 0.005, 0.028 and 0.023, respectively). The univariate analysis recognized level of PLR ≥ 141.74 as significant risk factor of the recurrence of vocal fold hypertrophic lesions (OR = 1.963).

Conclusions

The levels of blood cells and their ratios seem to be effective in predicting the recurrence of lesion and even more their potential role in indicating malignant progression.

Role of Peripheral Blood Markers for Detecting Response and Predicting Prognosis in Patients with Non-small-cell Lung Cancer Undergoing Neoadjuvant Therapy and Surgery

INTRODUCTION

To date, no validated predictors of response before neoadjuvant therapy (NAD) are currently available in locally advanced non-small-cell lung cancer (NSCLC). In this study, different peripheral blood markers were investigated before NAD (pre-NAD) and after NAD/before surgery (post-NAD) to evaluate their influence on the treatment outcomes.

METHODS

Patients affected by locally advanced NSCLC (cT1-T4/N0-2/M0) who underwent NAD followed by surgery from January 1996 to December 2019 were considered for this retrospective analysis. The impact of peripheral blood markers on downstaging post-NAD and on overall survival (OS) was evaluated using multivariate logistic and Cox regression models. Time to event analysis was performed by means of Kaplan-Meier survival curves and Log Rank tests at 5 years from surgery.

RESULTS

Two hundred and seventy-two consecutive patients were included. Most of the patients had Stage III NSCLC (83.5%). N2 disease was reported in 188 (69.1%) patients. Surgical resection was performed in patients with stable disease or downstaging post-NAD. Nodal downstaging was observed in 80% of clinical N2 (cN2) patients. The median follow-up of the total series was 74 months (range 6-302). Five-year OS in the overall population and in N2 population was 74.6% and 73.5%, respectively. The pre-surgery platelets level (PLT) (p = 0.019) and the variation (pre-NAD/post-NAD) of the neutrophil/lymphocyte ratio (p = 0.024) were identified as independent prognostic factors of OS. The preoperative PLT value (p value = 0.031) was confirmed as the only predictor of NAD response.

CONCLUSIONS

The clinical role of peripheral blood markers in locally advanced NSCLC needs to be further investigated. Based on these preliminary results, these factors may be used as auxiliary markers for the prediction of response to neoadjuvant treatment and as prognostic factors for stratification in multimodal approaches.

A systematic review of multimodal clinical biomarkers in the management of thyroid eye disease

Thyroid Eye Disease (TED) is an autoimmune disease that affects the extraocular muscles and periorbital fat. It most commonly occurs with Graves' Disease (GD) as an extrathyroidal manifestation, hence, it is also sometimes used interchangeably with Graves' Ophthalmopathy (GO). Well-known autoimmune markers for GD include thyroid stimulating hormone (TSH) receptor antibodies (TSH-R-Ab) which contribute to hyperthyroidism and ocular signs. Currently, apart from radiological investigations, detection of TED is based on clinical signs and symptoms which is largely subjective, with no established biomarkers which could differentiate TED from merely GD. We evaluated a total of 28 studies on potential biomarkers for diagnosis of TED. Articles included were published in English, which investigated clinical markers in tear fluid, orbital adipose-connective tissues, orbital fibroblasts and extraocular muscles, serum, thyroid tissue, as well as imaging biomarkers. Results demonstrated that biomarkers with reported diagnostic power have high sensitivity and specificity for TED, including those using a combination of biomarkers to differentiate between TED and GD, as well as the use of magnetic resonance imaging (MRI). Other biomarkers which were upregulated include cytokines, proinflammatory markers, and acute phase reactants in subjects with TED, which are however, deemed less specific to TED. Further clinical investigations for these biomarkers, scrutinising their specificity and sensitivity on a larger sample of patients, may point towards selection of suitable biomarkers for aiding detection and prognosis of TED in the future.

Accurate prediction of acute pancreatitis severity based on genome-wide cell free DNA methylation profiles

Background

Patients with severe acute pancreatitis (SAP) have a high mortality, thus early diagnosis and interventions are critical for improving survival. However, conventional tests are limited in acute pancreatitis (AP) stratification. We aimed to assess AP severity by integrating the informative clinical measurements with cell free DNA (cfDNA) methylation markers.

Methods

One hundred and seventy-five blood samples were collected from 61 AP patients at multiple time points, plus 24 samples from healthy individuals. Genome-wide cfDNA methylation profiles of all samples were characterized with reduced representative bisulfite sequencing. Clinical blood tests covering 93 biomarkers were performed on AP patients within 24 h. SAP predication models were built based on cfDNA methylation and conventional blood biomarkers separately and in combination.

Results

We identified 565 and 59 cfDNA methylation markers informative for acute pancreatitis and its severity. These markers were used to develop prediction models for AP and SAP with area under the receiver operating characteristic of 0.92 and 0.81, respectively. Twelve blood biomarkers were systematically screened for a predictor of SAP with a sensitivity of 87.5% for SAP, and a specificity of 100% in mild acute pancreatitis, significantly higher than existing blood tests. An expanded model integrating 12 conventional blood biomarkers with 59 cfDNA methylation markers further improved the SAP prediction sensitivity to 92.2%.

Conclusions

These findings have demonstrated that accurate prediction of SAP by the integration of conventional and novel blood molecular markers, paving the way for early and effective SAP intervention through a non-invasive rapid diagnostic test.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-021-01217-z.

A novel model based on interleukin 6 and insulin-like growth factor II for detection of hepatocellular carcinoma associated with hepatitis C virus

BACKGROUND

The coexistence of cirrhosis complicates the early detection of hepatocellular carcinoma (HCC). Thus, novel biomarkers for HCC early detection are needed urgently. Traditionally, HCC detection is carried out by evaluating alpha-fetoprotein (AFP) levels combined with imaging techniques. This work aimed to assess interleukin (IL-6) and insulin-like growth factor 2 (IGF 2) as possible HCC markers in comparison to AFP in patients with and without HCC.

RESULTS

ROC analysis showed that IGF2 had the highest area under the curve (AUC) for discriminating HCC from liver cirrhosis (0.86), followed by IL6 (0.82), AFP (0.72), and platelet count (0.6). A four-marker model was developed and discriminated HCC from liver cirrhosis with an AUC of 0.97. The best cut-off was 1.28, at which sensitivity and specificity were 90% and 85%, respectively. For small tumor (< 2 cm), the model had an AUC of 0.95 compared to AFP (0.72). Also, the model achieved perfect performance with AUC of 0.93, 0.94, and 0.95 for BCLC (0-A), CLIP (0-1), and Okuda (stage I), respectively, compared to AFP (AUC of 0.71, 0.69, and 0.67, respectively).

CONCLUSIONS

The four markers may serve as a diagnostic model for HCC early stages and help overcome AFP poor sensitivity.

Associations between major psychiatric disorder polygenic risk scores and blood-based markers in UK biobank

Major depressive disorder (MDD), schizophrenia (SCZ), and bipolar disorder (BD) have both shared and discrete genetic risk factors, and are associated with peripheral abnormalities. The relationships between such genetic architectures and blood-based markers are, however, unclear. We investigated relationships between polygenic risk scores (PRS) for these disorders and peripheral markers in the UK Biobank cohort. We calculated polygenic risk scores for n = 367,329 (MDD PRS), n = 366,465 (SCZ PRS), and n = 366,383 (BD PRS) UK Biobank cohort subjects. We then examined associations between disorder PRS and 58 inflammatory/immune, hematological, bone, cardiovascular, hormone, liver, renal and diabetes-associated blood markers using two generalized linear regression models: 'minimally adjusted' controlling for variables such as age and sex, and 'fully adjusted' including additional lifestyle covariates: BMI, alcohol and smoking status, and medication intake. There were 38/58 MDD PRS, 32/58 SCZ PRS, and 20/58 BD PRS-blood marker associations detected for our minimally adjusted model. Of these, 13/38 (MDD PRS), 14/32 (SCZ PRS), and 10/20 (BD PRS) associations remained significant after controlling for lifestyle factors. Many were disorder-specific, with 8/13 unique MDD PRS associations identified. Several disorder-specific associations for MDD and SCZ were immune-related, with mostly positive and negative associations identified for MDD and SCZ PRS respectively. This study suggests that MDD, SCZ and BD have both shared and distinct peripheral markers associated with disorder-specific genetic risk. The results also implicate inflammatory dysfunction in MDD and SCZ, albeit with differences in patterns between the two conditions, and enrich our understanding of potential underlying pathophysiological mechanisms in major psychiatric disorders.

Exploring domains, clinical implications and environmental associations of a deep learning marker of biological ageing

Deep Neural Networks (DNN) have been recently developed for the estimation of Biological Age (BA), the hypothetical underlying age of an organism, which can differ from its chronological age (CA). Although promising, these population-specific algorithms warrant further characterization and validation, since their biological, clinical and environmental correlates remain largely unexplored. Here, an accurate DNN was trained to compute BA based on 36 circulating biomarkers in an Italian population (N = 23,858; age ≥ 35 years; 51.7% women). This estimate was heavily influenced by markers of metabolic, heart, kidney and liver function. The resulting Δage (BA-CA) significantly predicted mortality and hospitalization risk for all and specific causes. Slowed biological aging (Δage < 0) was associated with higher physical and mental wellbeing, healthy lifestyles (e.g. adherence to Mediterranean diet) and higher socioeconomic status (educational attainment, household income and occupational status), while accelerated aging (Δage > 0) was associated with smoking and obesity. Together, lifestyles and socioeconomic variables explained ~48% of the total variance in Δage, potentially suggesting the existence of a genetic basis. These findings validate blood-based biological aging as a marker of public health in adult Italians and provide a robust body of knowledge on its biological architecture, clinical implications and potential environmental influences.

Real-time fMRI neurofeedback amygdala training may influence kynurenine pathway metabolism in major depressive disorder

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rtfMRI-nf LA emotional training reduces depressive symptoms.

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rtfMRI-nf LA training increases KynA/3-HK, a neuroprotective index.

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Baseline KynA/QA is associated with the ability to upregulate the LA.

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In partial responder group LA upregulation positively correlates with KynA/QA.

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In partial responder group LA upregulation inversely correlates with MADRS.

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Modulation of the KP may drive rtfMRI-nf-induced changes in neuroplasticity.

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Non-specific effects cannot be ruled out due to the lack of a sham control.

Real-time fMRI neurofeedback (rtfMRI-nf) left amygdala (LA) training is a promising intervention for major depressive disorder (MDD). We have previously proposed that rtfMRI-nf LA training may reverse depression-associated regional impairments in neuroplasticity and restore information flow within emotion-regulating neural circuits. Inflammatory cytokines as well as the neuroactive metabolites of an immunoregulatory pathway, i.e. the kynurenine pathway (KP), have previously been implicated in neuroplasticity. Therefore, in this proof-of-principle study, we investigated the association between rtfMRI-nf LA training and circulating inflammatory mediators and KP metabolites. Based on our previous work, the primary variable of interest was the ratio of the NMDA-receptor antagonist, kynurenic acid to the NMDA receptor agonist, quinolinic acid (KynA/QA), a putative neuroprotective index. We tested two main hypotheses. i. Whether rtfMRI-nf acutely modulates KynA/QA, and ii. whether baseline KynA/QA predicts response to rtfMRI-nf.

Twenty-nine unmedicated participants who met DSM-5 criteria for MDD based on the Mini-International Neuropsychiatric Interview and had current depressive symptoms (Montgomery-Åsberg Depression Rating Scale (MADRS) score > 6) completed two rtfMRI-nf sessions to upregulate LA activity (Visit1 and 2), as well as a follow-up (Visit3) without rtfMRI-nf. All visits occurred at two-week intervals. At all three visits, the MADRS was administered to participants and serum samples for the quantification of inflammatory cytokines and KP metabolites were obtained. First, the longitudinal changes in the MADRS score and immune markers were tested by linear mixed effect model analysis. Further, utilizing a linear regression model, we investigated the relationship between rtfMRI-nf performance and immune markers. After two sessions of rtfMRI-nf, MADRS scores were significantly reduced (t[58] = −4.07, p = 0.009, d = 0.56). Thirteen participants showed a ≥ 25% reduction in the MADRS score (the partial responder group). There was a significant effect of visit (F[2,58] = 3.17, p = 0.05) for the neuroprotective index, KynA to 3-hydroxykynurenine (3-HK), that was driven by a significant increase in KynA/3-HK between Visit1 and Visit3 (t[58] = 2.50, p = 0.03, d = 0.38). A higher baseline level of KynA/QA (β = 5.23, p = 0.06; rho = 0.49, p = 0.02) was associated with greater ability to upregulate the LA. Finally, for exploratory purposes correlation analyses were performed between the partial responder and the non-responder groups as well as in the whole sample including all KP metabolites and cytokines. In the partial responder group, greater ability to upregulate the LA was correlated with an increase in KynA/QA after rtfMRI-nf (rho = 0.75, p = 0.03). The results are consistent with the possibility that rtfMRI-nf decreases metabolism down the so-called neurotoxic branch of the KP. Nevertheless, non-specific effects cannot be ruled out due to the lack of a sham control. Future, controlled studies are needed to determine whether the increase in KynA/3HK and KynA/QA is specific to rtfMRI-nf or whether it is a non-specific correlate of the resolution of depressive symptoms. Similarly, replication studies are needed to determine whether KynA/QA has clinical utility as a treatment response biomarker.

Plasma neurofilament light chain and amyloid-β are associated with the kynurenine pathway metabolites in preclinical Alzheimer's disease

Background

Blood markers indicative of neurodegeneration (neurofilament light chain; NFL), Alzheimer’s disease amyloid pathology (amyloid-β; Aβ), and neuroinflammation (kynurenine pathway; KP metabolites) have been investigated independently in neurodegenerative diseases. However, the association of these markers of neurodegeneration and AD pathology with neuroinflammation has not been investigated previously. Therefore, the current study examined whether NFL and Aβ correlate with KP metabolites in elderly individuals to provide insight on the association between blood indicators of neurodegeneration and neuroinflammation.

Methods

Correlations between KP metabolites, measured using liquid chromatography and gas chromatography coupled with mass spectrometry, and plasma NFL and Aβ concentrations, measured using single molecule array (Simoa) assays, were investigated in elderly individuals aged 65–90 years, with normal global cognition (Mini-Mental State Examination Score ≥ 26) from the Kerr Anglican Retirement Village Initiative in Ageing Health cohort.

Results

A positive correlation between NFL and the kynurenine to tryptophan ratio (K/T) reflecting indoleamine 2,3-dioxygenase activity was observed (r = .451, p < .0001). Positive correlations were also observed between NFL and kynurenine (r = .364, p < .0005), kynurenic acid (r = .384, p < .0001), 3-hydroxykynurenine (r = .246, p = .014), anthranilic acid (r = .311, p = .002), and quinolinic acid (r = .296, p = .003). Further, significant associations were observed between plasma Aβ40 and the K/T (r = .375, p < .0005), kynurenine (r = .374, p < .0005), kynurenic acid (r = .352, p < .0005), anthranilic acid (r = .381, p < .0005), and quinolinic acid (r = .352, p < .0005). Significant associations were also observed between plasma Aβ42 and the K/T ratio (r = .215, p = .034), kynurenic acid (r = .214, p = .035), anthranilic acid (r = .278, p = .006), and quinolinic acid (r = .224, p = .027) in the cohort. On stratifying participants based on their neocortical Aβ load (NAL) status, NFL correlated with KP metabolites irrespective of NAL status; however, associations between plasma Aβ and KP metabolites were only pronounced in individuals with high NAL while associations in individuals with low NAL were nearly absent.

Conclusions

The current study shows that KP metabolite changes are associated with biomarker evidence of neurodegeneration. Additionally, the association between KP metabolites and plasma Aβ seems to be NAL status dependent. Finally, the current study suggests that an association between neurodegeneration and neuroinflammation manifests in the periphery, suggesting that preventing cytoskeleton cytotoxicity by KP metabolites may have therapeutic potential.

Electronic supplementary material

The online version of this article (10.1186/s12974-019-1567-4) contains supplementary material, which is available to authorized users.

The Age-Well observational study on expert meditators in the Medit-Ageing European project

INTRODUCTION

The Age-Well observational, cross-sectional study investigates the affective and cognitive mechanisms of meditation expertise with behavioral, neuroimaging, sleep, and biological measures sensitive to aging and Alzheimer's disease (AD).

METHODS

Thirty cognitively unimpaired individuals aged 65 years or older with at least 10,000 hours of practice in mindfulness meditation (MM) and loving-kindness and compassion meditation (LKCM) are selected. The outcomes are the neuroimaging brain correlates of MM and LKCM and the assessments of long-term meditation practices on behavioral, neural, and biological measures as compared to nonmeditator older controls from the Age-Well randomized controlled trial.

RESULTS

Recruitment and data collection began in late 2016 and will be completed by late 2019.

DISCUSSION

Results are expected to foster the understanding of the effects of meditation expertise on aging and of the mechanisms of action underlying the meditation intervention in the Age-Well randomized controlled trial. These finding will contribute to the design of meditation-based prevention randomized controlled trials for the aged population and to the exploration of the possible long-time developmental trajectory of meditation training.

The Age-Well randomized controlled trial of the Medit-Ageing European project: Effect of meditation or foreign language training on brain and mental health in older adults

Introduction

The Age-Well clinical trial is an ongoing monocentric, randomized, controlled trial aiming to assess an 18-month preventive meditation-based intervention directly targeting the attentional and emotional dimensions of aging to promote mental health and well-being in elderly people.

Methods

One hundred thirty-seven cognitively unimpaired older adults are randomized to either an 18-month meditation-based intervention, a structurally matched foreign language training, or a passive control arm. The impact of the intervention and underlying mechanisms are assessed with detailed cognitive, behavioral, biological, neuroimaging and sleep examinations.

Results

Recruitment began in late 2016 and ended in May 2018. The interventions are ongoing and will be completed by early 2020.

Discussion

This is the first trial addressing the emotional and cognitive dimension of aging with a long-term nonpharmacological approach and using comprehensive assessments to investigate the mechanisms. Results are expected to foster the development of preventive strategies reducing the negative impact of mental conditions and disorders.

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Meditation or language training could improve mental health and well-being in aging.

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Age-Well is a randomized controlled trial targeting mental health in aging.

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Age-Well includes 18-month meditation and foreign language training in 137 elderly.

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Age-Well interventions are expected to positively impact brain structure and function.

Upgraded Methodology for the Development of Early Diagnosis of Parkinson's Disease Based on Searching Blood Markers in Patients and Experimental Models

Numerous attempts to develop an early diagnosis of Parkinson's disease (PD) by searching biomarkers in biological fluids were unsuccessful. The drawback of this methodology is searching markers in patients at the clinical stage without guarantee that they are also characteristic of either preclinical stage or prodromal stage (preclinical-prodromal stage). We attempted to upgrade this methodology by selecting only markers that are found both in patients and in PD animal models. HPLC and RT-PCR were used to estimate the concentration of amino acids, catecholamines/metabolites in plasma and gene expression in lymphocytes in 36 untreated early-stage PD patients and 52 controls, and in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice at modeling the clinical ("symptomatic") stage and preclinical-prodromal ("presymptomatic") stage of PD. It was shown that among 13 blood markers found in patients, 7 markers are characteristic of parkinsonian symptomatic mice and 3 markers of both symptomatic and presymptomatic mice. According to our suggestion, the detection of the same marker in patients and symptomatic animals indicates adequate reproduction of pathogenesis along the corresponding metabolic pathway, whereas the detection of the same marker in presymptomatic animals indicates its specificity for preclinical-prodromal stage. This means that the minority of markers found in patients-decreased concentration of L-3,4-dihydroxyphenylalanine (L-DOPA) and dihydroxyphenylacetic acid (DOPAC) and increased dopamine D3 receptor gene expression-are specific for preclinical-prodromal stage and are suitable for early diagnosis of PD. Thus, we upgraded a current methodology for development of early diagnosis of PD by searching blood markers not only in patients but also in parkinsonian animals.

The noninvasive diagnosis of esophageal varices and its application in clinical practice

Here, we review recent improvements made to different noninvasive tests used for the diagnosis of esophageal varices (EV) in the light of the recent Baveno VI recommendation and with an emphasis on clinical application. Like for fibrosis tests, these noninvasive EV tests can be classified as direct markers when they provide a visualization of EV (including all imaging procedures like endoscopy or radiology) and as indirect markers when they do not (blood markers or elastometry). Clinical descriptors expressed as percentages, especially the spared endoscopy rate and the missed high-risk esophageal varices (HREV) rate, are more eloquent in this setting than classical statistical descriptors like accuracy. Single biomarkers are insufficient, generally due to a missed HREV rate exceeding the acceptable limit of 5% indicated in the Baveno VI consensus. Thus, biomarker combinations are currently garnering the most interest. The Baveno VI recommendation states that in alcoholic and viral cirrhoses, screening endoscopy can be safely set aside for patients with liver stiffness<20kPa and platelets>150G/L. The Baveno rule's mean missed HREV rate is<5% but its spared endoscopy rate is<20%. New combinations or stepwise algorithms show promise but must be validated. Going forward, the Baveno rule provides a simple noninvasive method to rule out HREV in clinical practice but the need for further research continues. The noninvasive diagnosis of HREV will be significantly improved by new, simple and affordable combinations.

Maturation of arteriovenous fistula: Analysis of key factors

The growing proportion of individuals suffering from chronic kidney disease has considerable repercussions for both kidney specialists and primary care. Progressive and permanent renal failure is most frequently treated with hemodialysis. The efficiency of hemodialysis treatment relies on the functional status of vascular access. Determining the type of vascular access has prime significance for maximizing successful maturation of a fistula and avoiding surgical revision. Despite the frequency of arteriovenous fistula procedures, there are no consistent criteria applied before creation of arteriovenous fistulae. Increased prevalence and use of arteriovenous fistulae would result if there were reliable criteria to assess which arteriovenous fistulae are more likely to reach maturity without additional procedures. Published studies assessing the predictive markers of fistula maturation vary to a great extent with regard to definitions, design, study size, patient sample, and clinical factors. As a result, surgeons and specialists must decide which possible risk factors are most likely to occur, as well as which parameters to employ when evaluating the success rate of fistula development in patients awaiting the creation of permanent access. The purpose of this literature review is to discuss the role of patient factors and blood markers in the development of arteriovenous fistulae.

Associations between measures of vascular structure and function and systemic circulating blood markers in humans

Examination of relationships between systemic markers and functional measures of arterial structure and function may assist in determining alternative indices of vascular regulation and designing and evaluating interventions to improve arterial structure and function. Twenty young healthy individuals, 20 older healthy men, and 26 individuals with coronary artery disease (CAD), comprising a spectrum of vascular health, participated. Systemic markers of vascular structure and function included: pro‐collagen type I C‐peptide (PIP) – marker of collagen synthesis, C‐telopeptide of type I collagen (CTX) – marker of collagen degradation, endothelin‐1 (ET‐1) ‐ vasoconstrictor, and interleukin‐6 (IL‐6) – inflammatory marker. Functional measures of arterial structure and function included carotid artery distensibility and brachial artery flow‐mediated dilation (FMD). Moderate positive relationships were observed between carotid distensibility and CTX and PIP (r = 0.57, P < 0.0001 and r = 0.47, P < 0.0001). A negative correlation exists between ET‐1 and FMD (r = −0.44, P = 0.0004); however, no relationship was observed between IL‐6 and FMD (P = 0.25). Over a broad range of vascular health, relationships were observed between markers of type I collagen turnover and arterial stiffness and between a marker of vasoconstriction and endothelial function. These results indicate that regulatory links, between the indices examined, exist. Therefore, monitoring systemic markers rather than functional vascular measures, may provide sufficient information about vascular health and should be considered in the design and evaluation of vascular interventions.

Multianalyte markers of schizophrenia and bipolar disorder: A preliminary study

Previous studies have identified altered molecular profiles in blood samples from individuals with schizophrenia and with bipolar disorder using multianalyte immunoassay platforms but there has been little comparison of the two groups in the same investigation. A total of 337 participants including 146 with schizophrenia, 79 with bipolar disorder, and 112 non-psychiatric controls had a blood sample drawn from which 166 analytes were measured. The initial dataset was split; classification models were developed in a training dataset and their performance evaluated in a test dataset. Principal component analysis was used to generate factor scores that were then compared between the groups. In a training set, a total of 7 independent factors were generated using 29 markers that were both normally distributed and significantly associated with diagnosis. Many of these analytes are components of the immune system and involved in the inflammatory response to infectious agents and foreign antigens. Two of the seven principal component scores discriminated between individuals with schizophrenia and with bipolar disorder; additional factors distinguished individuals with either schizophrenia or bipolar disorder from control individuals, while two factors were not significantly different between any of the diagnostic groups. In a test dataset, the schizophrenia vs. control Receiver Operating Curve (ROC) analysis shows an overall accuracy of 77% for schizophrenia vs. bipolar disorder, 84% for schizophrenia vs. controls, and 72% for bipolar disorder vs.

CONTROLS

An increased understanding of the role of altered pathways in serious psychiatric disorders may lead to novel methods for disease diagnosis and therapy.

Principal Component Analysis of Conformation and Blood Marker Traits at Pre- and Post-Weaning Stages of Growth in F2 Crossbred Nigerian Indigenous X Landrace Pigs

Linear body measurements and blood hematology and biochemistry parameters were taken on 92 and 15 grower pigs, respectively, chosen randomly from a crossbred F2 population of Nigerian Indigenous (NI) x Landrace pigs to evaluate body conformation and blood marker traits using a multivariate approach. For linear body measurements at pre-weaning stage (4 weeks old), two principal components accounted for 91.63% of the total variation in body conformation traits, while at post weaning stage (12 weeks old), one principal component accounted for 73.63% of the total variations in body conformation traits. The first factor (principal component) accounted for 72.34% of the total variance (body weight) while the second factor accounted for 19.29% (ear length) at pre-weaning stage. While at post-weaning stage only one factor contributed to the total variability of the original six traits tested, with 73.63% (body length). For blood parameters, three principal components accounted for 81.85% of the total variation at pre-weaning stage while 89.44% of the total variation at post-weaning stage was accounted for by four principal components. The first factor (principal component) accounted for 38.048% (Packed cell volume), the second accounted for 24.72% (hemoglobin) and the third accounted for 19.08% (aspartate transaminase). While at the post-weaning stage, the first factor was influenced by red blood corpuscles (37.17%), the second factor had its loading for hemoglobin (25.80%), the third factor had loading for white blood corpuscles (13.67%), while the fourth factor had loading for alkaline phosphatase only (12.80%). Using communality extraction factors, ear length best described body conformation at the pre-weaning stage; whereas, at post-weaning stage, body length was the best descriptor. In blood parameters, packed cell volume best described blood marker traits at the pre-weaning stage; whereas, at the post-weaning stage, red blood corpuscles best described it. Hence, the two extracted factors in linear body measurements and in blood parameters could be considered in breeding programs to improve and predict body conformation in crossbred pigs, as well as predict blood marker traits.

Identification of high responders for interleukin-6 and creatine kinase following acute eccentric resistance exercise in elderly obese women

OBJECTIVES

Resistance exercise is used as a non-pharmacological tool to elicit both gains in and maintenance of physical function in the elderly. Thus, the present study examined the acute response of creatine kinase and interleukin-6 following an eccentric resistance exercise session in elderly obese women classified as high responders or normal responders.

DESIGN

Cross-sectional field study.

METHODS

Ninety elderly obese women (69.4 ± 6.01 years) were tested for a 10 repetition maximum on the leg extension exercise and then completed an acute eccentric resistance exercise session consisting of seven sets of 10 repetitions at 110% of 10 repetition maximum with a rest of 3 min between sets. Subjects were divided into normal response or high response on the basis of the peak serum interleukin-6 (NR = 59 and HR = 7) and creatine kinase (NR = 81 and HR = 9) concentration being greater than (HR) or less than (NR) the 90th percentile.

RESULTS

Creatine kinase was higher at 0 h, 3h, 24h and 48 h following the ERE for the HR group. The peak creatine kinase was significantly higher in HR group versus the normal response group. The average increase in the serum interleukin-6 Δ for the HR group (∼ 850%) was significantly higher versus the normal response group (∼ 55%). Serum interleukin-6 was significantly higher at 0 h and 24h following eccentric resistance exercise only for the high response group, while peak levels were significantly higher in high response group versus the normal response group (p ≤ 0.005). Only one subject met the criteria to be classified as high response for both creatine kinase and interleukin-6 responsiveness.

CONCLUSIONS

Elderly individuals classified as high response experienced greater creatine kinase and interleukin-6 responses to ERE. Thus, a prudent approach for eccentric resistance exercise prescription might be programming additional recovery days and/or lower intensity training, especially in the beginning stages of a program.