Influence of blood lipids on plasma and blood viscosity

Comprehensive Audiologic Analyses After Cisplatin-Based Chemotherapy

Importance

Cisplatin is highly ototoxic but widely used. Evidence is lacking regarding cisplatin-related hearing loss (CRHL) in adult-onset cancer survivors with comprehensive audiologic assessments (eg, Words-in-Noise [WIN] tests, full-spectrum audiometry, and additional otologic measures), as well as the progression of CRHL considering comorbidities, modifiable factors associated with risk, and cumulative cisplatin dose.

Objective

To assess CRHL with comprehensive audiologic assessments, including the WIN, evaluate the longitudinal progression of CRHL, and identify factors associated with risk.

Design, Setting, and Participants

The Platinum Study is a longitudinal study of cisplatin-treated testicular cancer survivors (TCS) enrolled from 2012 to 2018 with follow-up ongoing. Longitudinal comprehensive audiologic assessments at Indiana University and Memorial Sloan Kettering Cancer Center included 100 participants without audiometrically defined profound hearing loss (HL) at baseline and at least 3.5 years from their first audiologic assessment. Data were analyzed from December 2013 to December 2022.

Exposures

Factors associated with risk included cumulative cisplatin dose, hypertension, hypercholesterolemia, diabetes, tobacco use, physical inactivity, body mass index, family history of HL, cognitive dysfunction, psychosocial symptoms, and tinnitus.

Main Outcomes and Measures

Main outcomes were audiometrically measured HL defined as combined-ears high-frequency pure-tone average (4-12 kHz) and speech-recognition in noise performance measured with WIN. Multivariable analyses evaluated factors associated with risk for WIN scores and progression of audiometrically defined HL.

Results

Median (range) age of 100 participants at evaluation was 48 (25-67) years; median (range) time since chemotherapy: 14 (4-31) years. At follow-up, 78 (78%) TCS had audiometrically defined HL; those self-reporting HL had 2-fold worse hearing than TCS without self-reported HL (48 vs 24 dB HL; P < .001). A total of 54 (54%) patients with self-reported HL showed clinically significant functional impairment on WIN testing. Poorer WIN performance was associated with hypercholesterolemia (β = 0.88; 95% CI, 0.08 to 1.69; P = .03), lower-education (F1 = 5.95; P = .004), and severity of audiometrically defined HL (β̂ = 0.07; 95% CI, 0.06 to 0.09; P < .001). CRHL progression was associated with hypercholesterolemia (β̂ = -4.38; 95% CI, -7.42 to -1.34; P = .01) and increasing age (β̂ = 0.33; 95% CI, 0.15 to 0.50; P < .001). Importantly, relative to age-matched male normative data, audiometrically defined CRHL progression significantly interacted with cumulative cisplatin dose (F1 = 5.98; P = .02); patients given 300 mg/m2 or less experienced significantly less progression, whereas greater temporal progression followed doses greater than 300 mg/m2.

Conclusions and Relevance

Follow-up of cisplatin-treated cancer survivors should include strict hypercholesterolemia control and regular audiological assessments. Risk stratification through validated instruments should include querying hearing concerns. CRHL progression relative to age-matched norms is likely associated with cumulative cisplatin dose; investigation over longer follow-up is warranted.

Mendelian randomization study of whole blood viscosity and cardiovascular diseases

AIMS

Association between whole blood viscosity (WBV) and an increased risk of cardiovascular disease (CVD) has been reported. However, the causal relationship between WBV and CVD remains not thoroughly investigated. The aim of this study was to investigate the causal relation between WBV and CVD.

METHODS

Two-sample Mendelian randomization (MR) was employed, with inverse variance weighting (IVW) as the primary method, to investigate the casual relationship between WBV and CVD. The calculated WBV and medical records of 378,210 individuals participating in the UK Biobank study were divided into halves and analyzed.

RESULTS

The means of calculated WBVs were 16.9 (standard deviation: 0.8) and 55.1 (standard deviation: 17.2) for high shear rate (HSR) and low shear rate (LSR), respectively. 37,859 (10.0%) major cardiovascular events (MACE) consisted of 23,894 (6.3%) cases of myocardial infarction (MI), 9,245 (2.4%) cases of ischemic stroke, 10,377 (2.7%) cases of revascularization, and 5,703 (1.5%) cases of coronary heart disease-related death. In the MR analysis, no evidence was found indicating a causal effect of WBV on MACE (IVW p-value for HSR = 0.81, IVW p-value for LSR = 0.47), MI (0.92, 0.83), ischemic stroke (0.52, 0.74), revascularization (0.71, 0.54), and coronary heart disease-related death (0.83, 0.70). The lack of sufficient evidence for causality persisted in other MR methods, including weighted median and MR-egger.

CONCLUSIONS

The Mendelian randomization analysis conducted in this study does not support a causal relationship between calculated WBV and CVD.

The Application of Fluorescence Anisotropy for Viscosity Measurements of Small Volume Biological Analytes

Time-resolved fluorescence anisotropy has been extensively used to detect changes in bimolecular rotation associated with viscosity levels within cells and other solutions. Physiological alterations of the viscosity of biological fluids have been associated with numerous pathological causes. This current work serves as proof of concept for a method to measure viscosity changes in small analyte volumes representative of biological fluids. The fluorophores used in this study were fluorescein disodium salt and Enhanced Green Fluorescent Protein (EGFP). To assess the ability of the method to accurately detect viscosity values in small volume samples, we conducted measurements with 12 μL and 100 μL samples. No statistically significant changes in determined viscosities were recorded as a function of sample volume for either fluorescent probe. The anisotropy of both fluorescence probes was measured in low viscosity standards ranging from 1.02 to 1.31 cP, representative of physiological fluid values, and showed increasing rotational correlation times in response to increasing viscosity. We also showed that smaller fluid volumes can be diluted to accommodate available cuvette volume requirements without a loss in the accuracy of detecting discrete viscosity variations. Moreover, the ability of this technique to detect subtle viscosity changes in complex fluids similar to physiological ones was assessed by using fetal bovine serum (FBS) containing samples. The presence of FBS in the analytes did not alter the viscosity specific rotational correlation time of EGFP, indicating that this probe does not interact with the tested analyte components and is able to accurately reflect sample viscosity. We also showed that freeze-thaw cycles, reflective of the temperature-dependent processes that biological samples of interest could undergo from the time of collection to analyses, did not impact the viscosity measurements' accuracy. Overall, our data highlight the feasibility of using time-resolved fluorescence anisotropy for precise viscosity measurements in biological samples. This finding is relevant as it could potentially expand the use of this technique for in vitro diagnostic systems.

Relationship between lipoprotein(a) and whole blood reducing viscosity: A cross-sectional study

Lipoprotein(a) [Lp(a)] has been confirmed as a causal risk factor of atherosclerotic cardiovascular disease, but its role on circulation is not completely clear and is still being explored. Therefore, this study attempts to explore the relationship between Lp(a) and whole blood reducing viscosity (WBRV), to better understand the role of Lp(a) in circulatory and cardiovascular diseases. We retrospectively analyzed the data of consecutive subjects in the physical examination center of the Affiliated Hospital of Ningbo University Medical College from January 2022 to May 2022. Pearson or spearman correlation analysis was used to test the statistical relationship between 2 continuous variables according to whether they are normal; 131 participants were retrospectively enrolled in this study. The low-density lipoprotein concentration was associated with whole blood viscosity at low-shear (R = 0.220, P = .012), middle-shear (R = 0.226, P = .01), and high-shear viscosity (R = 0.212, P = .015), as well as plasma viscosity (RS = 0.207, P = .018). Lp(a) was not associated with whole blood viscosity at low, middle, and high shear rates, but was associated with WBRV at low shear (RS = 0.204, P = .019) and middle shear rates (RS = 0.197, P = .024). Lp(a) is associated with high WBRV, which may impart more insights into the role of Lp(a) in cardiovascular disease.

The Molecular Size of Bioengineered Oxygen Carriers Determines Tissue Oxygenation in a Hypercholesterolemia Guinea Pig Model of Hemorrhagic Shock and Resuscitation

Polymerized human hemoglobin (PolyhHb) has shown promise in preclinical hemorrhagic shock settings. Different synthetic and purification schemes can control the size of PolyhHbs, yet research is lacking on the impact of polymerized hemoglobin size on tissue oxygenation following hemorrhage and resuscitation in specialized animal models that challenge their resuscitative capabilities. Pre-existing conditions that compromise the vasculature and end organs, such as the liver, may limit the effectiveness of resuscitation and exacerbate the toxicity of these molecules, which is an important but minimally explored therapeutic dimension. In this study, we compared the effective oxygen delivery of intermediate molecular weight PolyhHb (PolyhHb-B3; 500-750 kDa) to high molecular weight PolyhHb (PolyhHb-B4; 750 kDa-0.2 μm) for resuscitative effectiveness in guinea pig models subjected to hemorrhagic shock. We evaluated how the size of PolyhHb impacts hemodynamics and tissue oxygenation in normal guinea pigs and guinea pigs on an atherogenic diet. We observed that while PolyhHb-B3 and -B4 equivalently restore hemodynamic parameters of normal-dieted guinea pigs, high-fat-dieted guinea pigs resuscitated with PolyhHb-B4 have lower mean arterial pressures, impaired tissue oxygenation, and higher plasma lactate levels than those receiving PolyhHb-B3. We characterized the plasma of these animals following resuscitation and found that despite similar oxygen delivery kinetics, circulating PolyhHb-B3 and -B4 demonstrated a size-dependent increase in the plasma viscosity, consistent with impaired perfusion in the PolyhHb-B4 transfusion group. We conclude that intermediate-sized PolyhHbs (such as -B3) are ideal for further research given the effective resuscitation of hemorrhagic shock based on tissue oxygenation in hypercholesterolemic guinea pigs.

Nephrotic syndrome: pathophysiology and consequences

In patients with kidney disease, nephrotic syndrome can lead to several complications including progressive kidney dysfunction. Proteinuria may lead to the formation of cellular or fibrous crescents with reciprocal development of rapidly progressive glomerulonephritis or focal glomerulosclerosis. Proteinuria may also cause overload and dysfunction of tubular epithelial cells, eventually resulting in tubular atrophy and interstitial fibrosis. Hypoalbuminemia is usually associated with increased risk of mortality and kidney dysfunction. Dyslipidemia may increase the risk of atherosclerotic complications, cause podocyte dysfunction and contribute to vascular thrombosis. Urinary loss of anticoagulants and overproduction of coagulation factors may facilitate a hypercoagulable state. Edema, hypogammaglobulinemia, loss of complement factors, and immunosuppressive therapy can favor infection. Treatment of these complications may reduce their impact on the severity of NS. Nephrotic syndrome is a kidney disorder that can worsen the quality of life and increase the risk of kidney disease progression.

Comprehensive review on the pathogenesis of hypertriglyceridaemia-associated acute pancreatitis

It is well known, that the inflammatory process that characterizes acute pancreatitis (AP) can lead to both pancreatic damage and systemic inflammatory response syndrome (SIRS). During the last 20 years, there has been a growing incidence of episodes of acute pancreatitis associated with hypertriglyceridaemia (HTAP). This review provides an overview of triglyceride metabolism and the potential mechanisms that may contribute to developing or exacerbating HTAP. The article comprehensively discusses the various pathological roles of free fatty acid, inflammatory response mechanisms, the involvement of microcirculation, serum calcium overload, oxidative stress and the endoplasmic reticulum, genetic polymorphism, and gut microbiota, which are known to trigger or escalate this condition. Future perspectives on HTAP appear promising, with ongoing research focused on developing more specific and effective treatment strategies.

Effectiveness and Safety of Fufang Danshen Dripping Pill (Cardiotonic Pill) on Blood Viscosity and Hemorheological Factors for Cardiovascular Event Prevention in Patients with Type 2 Diabetes Mellitus: Systematic Review and Meta-Analysis

Background and Objectives: Diabetes can cause various vascular complications. The Compounded Danshen-Dripping-Pill (CDDP) is widely used in China. This study aimed to analyze the effectiveness and safety of CDDP in the blood viscosity (BV) with type 2 diabetes mellitus (T2DM). Materials and Methods: We conducted a systematic search of seven databases from their inception to July 2022 for randomized controlled trials that used CDDP to treat T2DM. To evaluate BV, we measured low shear rate (LSR), high shear rate (HSR), and plasma viscosity (PV). Homocysteine and adiponectin levels were also assessed as factors that could affect BV. Results: We included 18 studies and 1532 patients with T2DM. Meta-analysis revealed that CDDP significantly reduced LSR (mean difference [MD] -2.74, 95% confidence interval [CI] -3.77 to -1.72), HSR (MD -0.86, 95% CI -1.08 to -0.63), and PV (MD -0.37, 95% CI -0.54 to -0.19) compared to controls. CDDP also reduced homocysteine (MD -8.32, 95% CI -9.05 to -7.58), and increased plasma adiponectin (MD 2.72, 95% CI 2.13 to 3.32). Adverse events were reported less frequently in the treatment groups than in controls. Conclusions: CDDP is effective in reducing BV on T2DM. However, due to the poor design and quality of the included studies, high-quality, well-designed studies are required in the future.

Risk Factors for Primary Angle-closure Glaucoma: A Systematic Review and Meta-analysis of 45 Studies

SIGNIFICANCE

This study summarized primary angle-closure glaucoma (PACG)-related factors across different dimensions.

OBJECTIVES

This review aimed at systematically summarizing the associated factors of PACG in published literatures.

METHODS

A systematic review and meta-analysis were conducted by searching the electronic databases including PubMed, EMBASE, and Web of Science from their inception to November 2021. The pooled risk estimates of continuous and categorical variables were calculated using weighted mean difference (WMD) and odds ratio (OR; 95% confidence intervals [CIs]), respectively.

RESULTS

We included 45 studies in this review. In the meta-analysis, intraocular pressure (WMD, 3.13; 95% CI, 2.37 to 3.89), anterior chamber depth (WMD, -0.52; 95% CI, -0.70 to -0.34), axial length (WMD, -0.77; 95% CI, -1.26 to -0.28), retinal nerve fiber layer (WMD, -21.23; 95% CI, -30.21 to -12.25), and spherical equivalent (WMD, 1.02; 95% CI, 0.66 to 1.38) were the most common ophthalmic anatomic factors, and lower body weight (WMD, -3.65; 95% CI, -6.48 to -0.82) was the most significant general morphological indicators. The presence of cataract (OR, 3.77; 95% CI, 3.46 to 4.11) and hyperlipidemia (OR, 1.10; 95% CI, 1.02 to 1.20) were significantly associated with PACG. Increased level of triglyceride (WMD, 0.17; 95% CI, 0.06 to 0.27) was associated with PACG. In addition, an association between short-term antidepressant exposure (OR, 1.36; 95% CI, 1.08 to 1.70) and acute angle-closure glaucoma was observed.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

This review identified a few consistent factors related to PACG, providing important information for primary care physicians, general ophthalmologists, and public health professionals to counsel their patients on PACG risks.

Can Assessment of Rheological Properties of Whole Blood and Plasma Be Useful in the Diagnosis of Tinnitus? A Pilot Study

Tinnitus is a sensation of ringing in the ears in the absence of any physical source in the environment. Between 9-35% of adults experience some form of tinnitus. Common causes of tinnitus include noise, head injury, ototoxic substances, as well as disorders of blood and blood vessels. Vascular causes include: head-neck tumours, turbulent blood flow, problems with blood supply and inner ear cell damage. The aspect of rheology in terms of tinnitus has not been described yet. In the present study, which comprised 12 patients aged 30 to 74 years presenting with tinnitus, rheological properties of whole blood and plasma were assessed. All the subjects underwent audiological and neurological evaluation. The Quemada model was used to describe the variability of red blood cell shape, as well as their tendency to form aggregates. On the basis of the experimental study, statistically different results of haemorheological measurements were observed in the evaluated group in comparison to a reference group.

Effects of sarpogrelate on blood viscosity

The objective of the present study was to evaluate the effects and safety of sarpogrelate hydrochloride (sarpogrelate) in patients with elevated blood viscosity (BV), after 12 and 24 weeks of twice (BID) or thrice (TID) daily administrations of sarpogrelate (100 mg). The participants received oral sarpogrelate administration for 24 weeks and visited the hospital every 12 ± 2 week for blood viscosity measurements at shear rates of 5 and 300 s^-1. The BV measured at shear rate of 5 s^-1 in male patients decreased significantly from 18.91 cP at the baseline to 16.3 cP after 24 weeks of sarpogrelate administration (13.6 % drop, p < 0.001). The BV measured at 5 s^-1 in female decreased more significantly from 17.5 cP at the baseline to 13.4 cP after 24 weeks of sarpogrelate administration (23.0 % drop, p < 0.001). In summary, sarpogrelate may be considered as a possible therapeutic option for improving BV in patients with elevated blood viscosity. In particular, the reduction of the low-shear BV with the help of a viscosity-reducing drug such as sarpogrelate may be considered as a potentially new pharmacological tool for microvascular disease.

Design of Smart Aggregates: Toward Rapid Clinical Diagnosis of Hyperlipidemia in Human Blood

Molecular aggregates with environmental responsive properties are desired for their wide practical applications such as bioprobes. Here, a series of smart near-infrared (NIR) luminogens for hyperlipidemia (HLP) diagnosis is reported. The aggregates of these molecules exhibit a twisted intramolecular charge-transfer effect in aqueous media, but aggregation-induced emission in highly viscous media due to the restriction of the intramolecular motion. These aggregates, which can autonomously respond to different environments via switching the aggregation state without changing their chemical structures are described, as "smart aggregates". Intriguingly, these luminogens demonstrate NIR-II and NIR-III luminescence with ultralarge Stokes shifts (>950 nm). Both in vitro detection and in vivo imaging of HLP can be realized in a mouse model. Linear relationships exist between the emission intensity and multiple pathological parameters in blood samples of HLP patients. Thus, the design of smart aggregate facilitates rapid and accurate detection of HLP and provides a promising attempt in aggregate science.

Analysis of diastolic left ventricular wall shear stress in normal people of different age groups

Background

Diastolic wall shear stress (WSS), assessed by using vector flow mapping (VFM), is the result of the interaction between the blood flow and the ventricular wall. This study aimed to evaluate the trend of left ventricular (LV) WSS in normal subjects.

Methods and results

A total of 371 healthy volunteers were recruited and divided into four age groups (group I: 18–30 years; group II: 31–43 years; group III: 44–56 years; group IV: 57–70 years). LV WSS of different age groups was measured at each diastolic phase (P1: isovolumic diastolic period, P2: rapid filling period, P3: slow filling period, and P4:atrial contraction period) to evaluate the change trend of LV WSS. In each age group, LV WSS coincided with a trend of increasing-decreasing-increasing during P1–P4 (P < 0.05). Besides, among groups I, II, III, and IV, WSS of anterolateral, inferoseptal, and anteroseptal in P1 and WSS of inferolateral, inferoseptal, and anteroseptal in P4 all showed an increasing trend with age (P < 0.05). Regarding sex differences, women had greater diastolic WSS compared to men (P < 0.05).

Conclusion

LV WSS showed a regular variation and had specific age- and sex-related patterns in different diastolic phases.

Edible Bird’s Nest Regulates Hepatic Cholesterol Metabolism through Transcriptional Regulation of Cholesterol Related Genes

Objective. Hypercholesterolemia is a strong risk factor for cardiovascular diseases. Side effects associated with the use of pharmaceutical agents can cancel out their benefits. Dietary management of hypercholesterolemia is, therefore, receiving much attention due to fewer side effects. In this study, we explored the effectiveness of edible bird’s nest (EBN) in the prevention of hypercholesterolemia in rats. Methods. High-cholesterol diet (HCD) (4.5% cholesterol and 0.5% cholic acid) with or without EBN (low (2.5%) or high dose (20%)) was given to rats for 12 weeks, and their weights were observed. Simvastatin (10 mg/kg/day) was administered for the same period as a control drug. Serum and tissue samples were collected at the end of the study, from which biochemical parameters (lipid profiles, oxLDL, liver enzymes, urea, creatinine, uric acid, and lipase activity) and hepatic mRNA levels were measured. Results. The HCD group had higher levels of serum lipids, liver enzymes, uric acid, urea, and lipase activity compared with those of the other groups. The hepatic mRNA levels of cholesterol metabolism genes (APOB, PCSK9, HMGCR, LDLR, and CYP7A1) in the HCD group also tended toward increased cholesterol production and reduced cholesterol clearance. EBN, especially the highest dose, attenuated the HCD-induced changes, partly through improving the transcriptional regulation of hepatic cholesterol metabolism genes with fold changes of 0.7, 0.6, 0.5, 1.7, and 2.7, respectively, in comparison to the HCD group. In fact, EBN produced better results than simvastatin. Conclusion. Thus, the results suggest that EBN can regulate cholesterol metabolism and, therefore, be a source of functional ingredients for the management of hypercholesterolemia.

Prediction of Blood Viscosity Based on Usual Hematological Parameters in a Clinically Healthy Population Living in a High-Altitude City

Huamaní, Charles, William Sarmiento, Golda Córdova-Heredia, Luz Cruz-Huanca, Paulina Damián-Saavedra, and Dario Antonio. Prediction of blood viscosity based on usual hematological parameters in a clinically healthy population living in a high-altitude city. High Alt Med Biol. 23:78-84, 2022. Background and Aims: Variations in blood viscosity are mainly determined by the hematocrit level, but in residents of high-altitude cities, the hemoglobin levels and blood viscosity values are often high. We aimed to determine the blood viscosity values in clinically healthy chronic hypoxia-acclimatized individuals and establish a predictive model based on the hematocrit level and other common hematological parameters. Methods: A prospective observational study was conducted in asymptomatic young adults living in Cusco (a city located at 3,399 m). Venous blood samples were collected to determine the hemoglobin, hematocrit, and albumin and serum protein levels and blood viscosity values. Results: Altogether, 253 volunteers were included, of whom 147 (58.1%) were women. The hematological values were mean values of hemoglobin, 16.32 ± 2.0 g/dl; hematocrit, 48.12% ± 5.24%; triglycerides, 130.68 ± 90.64 mg/dl; globulin, 3.07 ± 0.36 g/dl; and mean blood viscosity, 6.17 ± 0.94 centipoises. The prediction model with the highest explained variance (R² = 68.07%) and parsimony conservation comprised hematocrit, globulin, and triglycerides [blood viscosity = hematocrit × (0.176) + globulin × (0.595) + triglycerides × (1.77/1,000) - 4.13]. Conclusions: In a population living at high altitude, the blood viscosity level is extremely high and mainly determined by the hematocrit level. This population has chronic high blood viscosity levels, which can be predicted using other blood elements.

Blood Viscosity in Subjects With Type 2 Diabetes Mellitus: Roles of Hyperglycemia and Elevated Plasma Fibrinogen

The viscosity of blood is an indicator in the understanding and treatment of disease. An elevated blood viscosity has been demonstrated in patients with Type 2 Diabetes Mellitus (T2DM), which might represent a risk factor for cardiovascular complications. However, the roles of glycated hemoglobin (HbA_1c) and plasma fibrinogen levels on the elevated blood viscosity in subjects with T2DM at different chronic glycemic conditions are still not clear. Here, we evaluate the relationship between the blood viscosity and HbA_1c as well as plasma fibrinogen levels in patients with T2DM. The experimental data show that the mean values of the T2DM blood viscosity are higher in groups with higher HbA_1c levels, but the correlation between the T2DM blood viscosity and the HbA_1c level is not obvious. Instead, when we investigate the influence of plasma fibrinogen level on the blood viscosity in T2DM subjects, we find that the T2DM blood viscosity is significantly and positively correlated with the plasma fibrinogen level. Further, to probe the combined effects of multiple factors (including the HbA_1c and plasma fibrinogen levels) on the altered blood viscosity in T2DM, we regroup the experimental data based on the T2DM blood viscosity values at both the low and high shear rates, and our results suggest that the influence of the elevated HbA_1c level on blood viscosity is quite limited, although it is an important indicator of glycemic control in T2DM patients. Instead, the elevated blood hematocrit, the enhanced red blood cell (RBC) aggregation induced by the increased plasma fibrinogen level, and the reduced RBC deformation play key roles in the determination of blood viscosity in T2DM. Together, these experimental results are helpful in identifying the key determinants for the altered T2DM blood viscosity, which can be used in future studies of the hemorheological disturbances of T2DM patients.

Association between Statin Use and Sensorineural Hearing Loss in Type 2 Diabetic Patients: A Hospital-Based Study

Statins have emerged as protective agents against sensorineural hearing loss (SNHL) associated with dyslipidemia, but the effects of statins on SNHL are not consistent. The purpose of this study was to investigate the association between statin use and the risk of SNHL using a hospital cohort. This nested case-control study included type 2 diabetic patients over the age of 18 years without a history of hearing loss. Of these, 1379 patients newly diagnosed with SNHL or tinnitus were classified as cases, and 5512 patients matched to the cases based on age, sex, and index year were classified as controls. Chi-squared tests were used to compare categorical variables between the two groups. Odds ratios (ORs) and adjusted odds ratios (AOR) were calculated from univariate and multivariable unconditional logistic regression analyses, respectively. There was a significant difference in the prevalence of statin use between the cases and controls (53.7% vs. 61.2%, respectively; p < 0.001). The use of statins in type 2 diabetic patients significantly reduced the risk of SNHL or tinnitus by 24.8% (95% CI 14.2–34.1%, p < 0.001) after controlling for confounders. Similar results were found for the association between statin use and SNHL (AOR = 0.706; 95% CI 0.616–0.811, p < 0.001). The protective effects of statins against SNHL were consistent regardless of age and sex. The use of statins for type 2 diabetic patients was significantly associated with a reduced risk of SNHL, regardless of age and sex. Further studies are needed, especially large cohort studies, to evaluate the long-term protective effects of statins.

Association of blood viscosity with first-pass reperfusion in mechanical thrombectomy for acute ischemic stroke

BACKGROUND

Elevated blood viscosity has been reported as a risk factor for cerebrovascular disease.

OBJECTIVE

The relationship between blood viscosity and outcomes of mechanical thrombectomy (MT) for large artery occlusion (LAO) were investigated in the present study.

METHODS

A total of 238 patients were enrolled and systolic blood viscosity (SBV) and diastolic blood viscosity (DBV) were measured using the scanning capillary tube viscometer. Receiver operating characteristic (ROC) analysis was performed to specify the association of viscosity with the first-pass reperfusion (FPR). Multivariable and regression analyses were performed to evaluate the relationship of viscosity with FPR and various variables.

RESULTS

Based on ROC analysis, the best DBV cutoff value was 10.55 (cP). In multivariable analysis, high DBV was associated with FPR failure (odds ratio 2.82, 95% confidence interval 1.64-4.22; p = 0.001). Increased DVB could be associated with elevated SBV, hematocrit level, and blood urea nitrogen/creatinine ratio (p = <0.001, 0.004, and 0.002, respectively).

CONCLUSIONS

Elevated DBV was associated with FPR failure. Patients with high DBV had longer thrombus length and required more stent passages than patients with low DBV.

Yanyu Decoction for Aged Patients with Stable Coronary Artery Disease: A Systematic Review and Meta-Analysis

Background

There was limited evidence of treatments aiming at aged coronary artery disease (CAD) patients. Yanyu decoction (YD) has been used as adjuvant therapy in aged patients with stable CAD and might be a new treatment worthy of recommendation for CAD patients. This study was to evaluate the combined effects of YD plus conventional pharmaceutical treatment (CPT) on senile patients with stable CAD.

Methods

This review was designed according to the PRISMA (Preferred Reported Items for Systematic Reviews and Meta-Analysis) recommendations. A literature search was conducted in seven electronic databases from their inception until August 2020. Primary outcomes of interest were adverse cardiovascular events, including cardiac mortality, acute myocardial infarction (AMI), and unstable angina (UA). The secondary outcomes were blood lipids and hemorheology. Studies were pooled to calculate the risk ratio or weighted mean difference and corresponding 95% confidence interval.

Results

Five studies recruiting 848 aged patients with stable CAD were included. Patients receiving YD as an adjuvant have fewer adverse cardiovascular events, including cardiac mortality, AMI, and UA. Besides, YD plus CPT has a better effect on reducing triglycerides, low-density lipoprotein cholesterol, and improving high-density lipoprotein cholesterol. Moreover, significant effects of YD plus CPT for reducing blood viscosity, plasma viscosity, and platelet aggregation rate were found compared with CPT alone.

Conclusion

YD plus CPT showed better efficacy than CPT on reducing adverse cardiovascular events and improving hemorheology and blood lipids for aged patients with stable CAD. Our findings may suggest YD as an adjuvant natural-based treatment for CAD. However, more rigorous and larger trials are essential to validate our results, and further consideration of CAD studies specific to aged patients is needed.

An assessment of the hemorheological profile in patients with subclinical carotid atherosclerosis divided in relation to the number of cardiovascular risk factors and different degrees of insulin resistance

We present a cohort of 100 subjects [43 men and 57 women; median age 66.00(25)] who were tested using carotid ultrasound to identify subclinical carotid atherosclerosis (SCA). We have evaluated the behaviour of whole blood viscosity (WBV) at high (450 s-1) and low (0.51 s-1) shear rates, plasma viscosity (450-1), hematocrit and mean erythrocyte aggregation. When compared to normal control subjects, using the Mann-Whitney test, we observed in SCA patients a significant increase in WBV only. The results were substantial after having divided the SCA subjects according to the cardiovascular risk factors (CRFs) and the degree of insulin resistance; the research was performed using two surrogate indexes such as TG/HDL-C and TyG. With the division carried out according to CRFs, employing the Kruskal-Wallis test, results show a significant increase in WBV (at high and low shear rates), in plasma viscosity, in erythrocyte aggregation and plasma fibrinogen level. Whereas by dividing them into the median of TG/HDL-C and TyG, we noticed a significant increase in WBV (at high and low shear rates) and in erythrocyte aggregation in the two groups with high TG/HDL-C ratio and with high TyG; having found an increased level of plasma fibrinogen in the latter. The data underlines the role of the main hemorheologic aspects in subclinical carotid atherosclerosis being closely correlated to the CRFs and different degrees of insulin resistance.

Effect of transport parameters on atherosclerotic lesion growth: A parameter sensitivity analysis

BACKGROUND

Atherosclerosis is a degenerative disease of the arterial wall. It results in the formation of progressively growing plaque lesions that can harden and narrow their host arteries. Current computational models of the inflammatory process that govern atherosclerosis growth are reliant on a number of parameters that can freely vary and whose precise values are not well known.

METHODS

To identify the significance of variation in such parameters, a parametric sensitivity study had been conducted on the blood density, blood viscosity, plasma viscosity and bulk flow low density lipoprotein (LDL) concentration. Using computational modeling, the significance of variation in these parameters was assessed on the transport of LDL. The simulation was performed via the 2^k factorial experimental design, which was conducted to identify the significance of the select parameters on the intima LDL concentration and endothelial LDL coverage area.

RESULTS

Results identified the blood viscosity and bulk flow LDL concentration are the dominant parameters for the atherosclerotic lesion growth. The coverage of LDL on the arterial wall surface was strongly dependent on the blood viscosity. The significance of these findings was discussed.

CONCLUSION

This statistical study identifies two dominating blood factors, LDL concentration and blood viscosity, and how they influence atherosclerosis which will serves as a guideline for further investigation on the atherosclerosis topic.

Successful treatment of cholesterol crystal embolism with anti-proprotein convertase subtilisin/kexin type 9 (PCSK9) antibody: a case report

Background

We report a unique case of renal cholesterol crystal embolism (CCE) induced by carotid artery stenting that was successfully treated with evolocumab, a fully human monoclonal antibody against proprotein convertase subtilisin kexin type 9 (PCSK9).

Case presentation

A 77-year-old man with hypertension, hyperlipidemia, and chronic kidney disease was referred to our department for decreased estimated glomerular filtration rate (eGFR)—from 32.0 to 13.9 mL/min/1.73 m²—5 weeks after carotid artery stenting. Further examination revealed livedo reticularis in the bilateral toes and eosinophilia (723/μL). Skin biopsy from livedo reticularis tissue in the bilateral toes showed cholesterol clefts in the small arteries. The patient was therefore diagnosed with CCE. After 25 weeks’ administration of evolocumab at a dose of 140 mg subcutaneously administered every 2 weeks, his eGFR had improved from 10.7 to 18.1 mL/min/1.73 m².

Conclusion

Evolocumab may have a beneficial effect on renal involvement in patients with CCE.

An Algorithm for the Noninvasive and Personalized Measurement of Microvascular Blood Viscosity Using Physiological Parameters

Blood viscosity is one of the important parameters to characterize hemorheological properties of the human body. Its real-time and dynamic measurement has important physiological significance for studying the development and prevention of chronic diseases. This study researched noninvasive and personalized measurement of microvascular blood viscosity. In the microcirculation capillary network blood flow model, combined with pulse wave parameters, multiple regression analysis was used to fit the simulated radius of personalized physiological blood vessels to calculate the microvascular blood viscosity. The fitted value related to the simulated radius of the physiological blood vessel had a high correlation with the corresponding theoretically derived value (correlation coefficient: 0.904, P ≤ 0.001). The calculated value of the microvascular blood viscosity had a certain correlation with the clinical whole blood viscosity at a low shear rate (correlation coefficient: 0.443, P < 0.05). This algorithm could provide effective means for noninvasive and long-term individual monitoring and family health care.

Benefits of physical exercise on cognition and glial white matter pathology in a mouse model of vascular cognitive impairment and dementia

White matter (WM) pathology is a clinically predictive feature of vascular cognitive impairment and dementia (VCID). Mice overexpressing transforming growth factor-β1 (TGF) with an underlying cerebrovascular pathology when fed a high cholesterol diet (HCD) develop cognitive deficits (VCID mice) that we recently found could be prevented by physical exercise (EX). Here, we further investigated cognitive and WM pathology in VCID mice and examined the cellular substrates of the protective effects of moderate aerobic EX focusing on WM alterations. Six groups were studied: Wild-type (WT) and TGF mice (n = 20-24/group) fed standard lab chow or a 2% HCD, with two HCD-fed groups given concurrent access to running wheels. HCD had a significant negative effect in TGF mice that was prevented by EX on working and object recognition memory, the latter also altered in WT HCD mice. Whisker-evoked increases in cerebral blood flow (CBF) were reduced in HCD-fed mice, deficits that were countered by EX, and baseline WM CBF was similarly affected. VCID mice displayed WM functional deficits characterized by lower compound action potential amplitude not found in EX groups. Moreover, there was an increased number of collapsing capillaries, galectin-3-expressing microglial cells, as well as a reduced number of oligodendrocytes in the WM of VCID mice; all of which were prevented by EX. Our findings indicate that a compromised cerebral circulation precedes reduced WM vascularization, enhanced WM inflammation and impaired oligodendrogenesis that all likely account for the increased susceptibility to memory impairments in VCID mice, which can be prevented by EX. MAIN POINTS: A compromised cerebral circulation increases susceptibility to anatomical and functional white matter changes that develop alongside cognitive deficits when challenged with a high cholesterol diet; preventable by a translational regimen of exercise.

The efficacy of statins as otoprotective agents: A systematic review

OBJECTIVE

This systematic review examined current literature, summarised research findings and identified research gaps regarding the efficacy of statins on audiological outcomes.

METHODS

Systematic search of electronic databases and grey literature was performed. Eligibility criteria were the study of a statin drug with report of audiological outcomes such as hearing, tinnitus or balance in either human or animal studies. Data extraction and quality assessment were performed by two independently researchers. The characteristics of the study and research findings were collated and summarised. A narrative synthesis was conducted. Meta-analysis was not possible due to heterogeneity of the included studies.

RESULTS

Analysis of searches yielded 17 studies meeting the criteria. Included studies had variable drug type and dosage, outcome measures and associated inner ear conditions. Most animal experiments showed promising audiological outcomes after statin treatment, demonstrated by the results of auditory brainstem response, distortion product otoacoustic emissions and inner ear histology. However, no clear effect can be discerned in human trials due to the mixed results, and heterogeneity in research methodology and quality. Audiological outcomes were not always correlated with cholesterol levels.

CONCLUSIONS

Statins remain a potential candidate as otoprotective agents which warrant further investigation.

Pulse-Wave-Pattern Classification with a Convolutional Neural Network

Owing to the diversity of pulse-wave morphology, pulse-based diagnosis is difficult, especially pulse-wave-pattern classification (PWPC). A powerful method for PWPC is a convolutional neural network (CNN). It outperforms conventional methods in pattern classification due to extracting informative abstraction and features. For previous PWPC criteria, the relationship between pulse and disease types is not clear. In order to improve the clinical practicability, there is a need for a CNN model to find the one-to-one correspondence between pulse pattern and disease categories. In this study, five cardiovascular diseases (CVD) and complications were extracted from medical records as classification criteria to build pulse data set 1. Four physiological parameters closely related to the selected diseases were also extracted as classification criteria to build data set 2. An optimized CNN model with stronger feature extraction capability for pulse signals was proposed, which achieved PWPC with 95% accuracy in data set 1 and 89% accuracy in data set 2. It demonstrated that pulse waves are the result of multiple physiological parameters. There are limitations when using a single physiological parameter to characterise the overall pulse pattern. The proposed CNN model can achieve high accuracy of PWPC while using CVD and complication categories as classification criteria.

1,25(OH)2D3 improves blood lipid metabolism, liver function, and atherosclerosis by constraining the TGF-β/Smad signaling pathway in rats with hyperlipidemia

1,25(OH)₂D₃ has already been reported to function in some diseases. However, its role in hyperlipidemia (HLP) remains unknown. This study aims to investigate the effect of 1,25(OH)₂D₃ on HLP rats. Rat models were established by high-fat diet feeding, perfusion of different doses of 1,25-(OH)₂D₃ and injection of TGF-β1 siRNA. Whole blood viscosity, plasma viscosity, hematocrit, and erythrocyte aggregation index were detected, together with levels of biochemical indexes, 6-keto-PGF1α, and TXB2 in serum. Levels of oxidative stress indexes and inflammatory factors in serum and liver tissues were determined. TGF-β1 and Smad3 expression in serum, liver tissues, and aorta was detected. 1,25(OH)₂D₃ lowered HLP-induced rise of whole blood viscosity, red blood cell aggregation index, plasma viscosity, and hematocrit, TC, TG, LDL-C, apoB, ALT, AST, TXB2, MDA, IL-1β, TNF-α, and increased HLP-induced decrease of HDL-C, apoAI, 6-keto-PGF1α, SOD, GSH-Px, CAT, and T-AOC. TGF-β1 and Smad3 expression in serum, liver tissue, and aorta of 1,25(OH)₂D₃-treated rats reduced. High 1,25(OH)₂D₃ dose and inhibited TGF-β/Smad signaling pathway alleviated lipid metabolism, liver function, and atherosclerotic injury in HLP rats. Our study found that 1,25(OH)₂D₃ improves blood lipid metabolism, liver function, and atherosclerosis injury by constraining the TGF-β/Smad signaling pathway in rats with HLP.

Fibrinogen and LDL Influence on Blood Viscosity and Outcome of Acute Ischemic Stroke Patients in Indonesia

BACKGROUND

To assess the role of risk factors of metabolic syndrome on blood viscosity and the prognosis of acute ischemic stroke in Indonesia based on the National Institute of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS).

METHODS

This study included 135 patients with acute ischemic stroke. Patients underwent measurements of viscosity and risk factor assessment. Analysis was performed to assess the role of these risk factors for blood viscosity and outcomes of acute ischemic stroke with NIHSS and mRS as indicators. NIHSS was assessed at <3 days after onset and 7 days after onset, while mRS was assessed 1 month post treatment. Bivariate analysis was performed using chi-square test, and variables with p < 0.25 were further analyzed in multivariate analysis using logistic regression.

RESULTS

Factors affecting blood viscosity are fibrinogen, low-density lipoprotein (LDL), and hematocrit. Factors affecting NIHSS and mRS are fibrinogen and LDL.

CONCLUSION

Fibrinogen and LDL affect the viscosity of blood and outcomes in acute ischemic stroke patients, so it is necessary to treat in the primary and secondary prevention of ischemic stroke.

Investigations on Multisensor-Based Noninvasive Blood Glucose Measurement System

Noninvasive blood glucose (NIBG) measurement technique has been explored for the last three decades to facilitate diabetes management. Photoplethysmogram (PPG) signal may be used to measure the variations in blood glucose concentration. However, the literature reveals that physiological perturbations such as temperature, skin moisture, and sweat lead to less accurate NIBG measurements. The task of minimizing the effect of these perturbations for accurate measurements is an important research area. Therefore, in the present work, galvanic skin response (GSR) and temperature measurements along with PPG were used to measure blood glucose noninvasively. The data extracted from the sensors were used to estimate blood glucose concentration with the help of two machine learning (ML) techniques, i.e., multiple linear regression (MLR) and artificial neural network (ANN). The accuracy of proposed multisensor system was evaluated by pairing and comparing noninvasive measurements with invasively measured readings. The study was performed on 50 nondiabetic subjects with body mass index (BMI) 27.3 ± 3 kg/m2. The results revealed that multisensor NIBG measurement system significantly improves mean absolute prediction error and correlation coefficient in comparison to the techniques reported in the literature.

Effects of Shenlian extract on experimental atherosclerosis in ApoE-deficient mice based on ultrasound biomicroscopy

Background

This study directly and dynamically investigated the effects of SL extract (i.e., a combination of Radix Salviae miltiorrhizae and Andrographis paniculata extract) on plaque progression in vivo by high resolution ultrasound biomicroscopy (UBM).

Methods

An atherosclerosis model was established by placing a perivascular collar on the right common carotid artery in apolipoprotein E-deficient (ApoE^-/-) mice. Thickness, plaque area and local blood flow were observed by UBM, pathological changes were observed by histochemical staining, and lipid levels were measured by respective commercially available kits.

Results

Compared with the model group, the SL extract groups showed reduced wall thickness of the aortic arch (GC: P = 0.001, P = 0.002, and P < 0.001; LC: P < 0.001, P < 0.001, and P < 0.001; BC: P = 0.027, P = 0.017, and P = 0.003; respectively), which presented with retarded plaque progression of the cartoid artery with concordantly increased blood flow (P = 0.002 and P < 0.001) as visualized in vivo by UBM. Histological analysis confirmed the reduction of carotid atherosclerosis.

Conclusions

The SL extract inhibited the formation of atherosclerotic plaques in an ApoE^-/- mice model by UBM analysis, and did so by effects that ameliorated local blood flow and improved blood lipid levels.

Effect of diabetic duration on hemorheological properties and platelet aggregation in streptozotocin-induced diabetic rats

Diabetes mellitus with abnormal glucose concentration is associated with changes in hemorheological properties, endothelial function, and platelets hyperactivity. Disturbances may significantly be responsible for diabetes-related vascular complications. In this study, hemorheological and hemodynamic properties were measured according to diabetic duration after streptozotocin treatment in rats. For ex vivo measurements, an extracorporeal model was adopted. Flow rate and blood viscosity were measured using a microfluidic device. Erythrocyte aggregation and morphological parameters of erythrocytes were measured by modified erythrocyte sedimentation rate and the phase-contrast holography under in vitro conditions. The platelet aggregation and mean pressure in the femoral artery were estimated under ex vivo conditions. Hemorheological properties including blood viscosity, erythrocyte aggregation and shape parameters for the control group are significantly different with those for diabetic groups. The changes with respect to diabetic duration were relatively unnoticeable. However, the platelet aggregation is strongly dependent on the diabetic duration. Based on these results, hyperglycemia exposure may induce hemorheological variations in early stages of diabetes mellitus. High platelet aggregation may become more pronounced according to the diabetic duration caused by variations in hemorheological properties resulting in endothelial dysfunction. This study would be helpful in understanding the effects of diabetic duration on biophysical properties.

The effects of weight loss surgery on blood rheology in severely obese patients

BACKGROUND

The effects of dieting on blood rheology in obese individuals suggest that improving the rheologic profiles depends on the amount of weight lost and its long-term maintenance. The aim of this study was to evaluate the effects of weight loss after surgery on blood rheology at 12-month follow-up.

METHODS

We studied 38 obese patients who underwent laparoscopic weight loss surgery, 22 of whom had sleeve gastrectomy (SG) and 16 of whom had gastric banding (LAGB). We evaluated rheologic parameters such as blood viscosity, plasma viscosity, and erythrocyte deformability (as measured by elongation index [EI]) preoperatively and 12 months after surgery.

RESULTS

Whole blood viscosity at 150 s(-1) shear rate (P<.01) and 300 s(-1) shear rate (P<.05), blood viscosity corrected to a standard hematocrit at both shear rates (P<.0005 and P<.005, respectively), and plasma viscosity (P<.005) were significantly reduced after surgery. EI evaluated at different shear stresses (18.49-60.03 Pa) decreased (P<.005) 12 months after surgery. There were significantly decreased EI and blood viscosity corrected to a standard hematocrit after SG (P<.005 and P<.05) and LAGB (P = .0621 and P<.05), but plasma viscosity significantly decreased only after SG (P<.005). Blood viscosity at both shear rates correlated with plasma viscosity (r = .51, P<.005 and r = .5, P<.005). Plasma viscosity correlated positively with body mass index (r = .57; P<.0005) and negatively with percentage of excess weight lost (r = -.56; P< .005).

CONCLUSIONS

This study found that weight loss after bariatric surgery induced improvement in blood rheology in obese patients at 12 months after surgery. The increased red blood cell rigidity after surgery requires further study because the physiologic importance of this change has not yet been established.

Acute carbon monoxide poisoning alters hemorheological parameters in human

Acute carbon monoxide (CO) poisoning seriously hinders oxygen delivery to tissues. This harmful effect of CO may be aggravated by accompanying changes in the viscosity of blood. We had previously reported increased plasma viscosity in people chronically exposed to CO. This study was planned to test our hypothesis that acute CO poisoning increases blood viscosity. For this purpose four main parameters contributing to blood viscosity - hematocrit, erythrocyte deformability, erythrocyte aggregation and plasma viscosity - were determined in patients with acute CO poisoning and compared with healthy controls. Plasma viscosity and erythrocyte aggregation tendency were lower in the CO group (p <  0.05). Erythrocyte deformability was also lower in CO group (p <  0.05). Our results indicate that acute CO poisoning has diverse effects on hemorheological parameters such as attenuating hematocrit value, plasma viscosity, erythrocyte aggregation tendency and erythrocyte deformability.

Complete blood count alterations after six months of continuous positive airway pressure treatment in patients with severe obstructive sleep apnea

STUDY OBJECTIVES

The cardiovascular complications caused by obstructive sleep apnea (OSA) decrease after continuous positive airway pressure treatment (CPAP). Mean platelet volume (MPV), platelet distribution width (PDW), and red cell distribution width (RDW) are newly recognized tools for assessing cardiovascular risk.

METHODS

From a selection of patients with symptoms of nocturnal snoring and/or excessive daytime sleepiness, 36 males with an apnea-hypopnea index (AHI) > 30/h and 22 age-matched normal male controls with AHI < 5/h were included. Patients with OSA underwent another night of CPAP titration, and 11 patients were excluded at the 6-month evaluation due to poor compliance with the home CPAP therapy. Complete blood count parameters of compliant patients and the control group were evaluated.

RESULTS

Compared to controls, MPV values were significantly higher (p = 0.025) in OSA patients, but no significant differences in PDW or RDW were found (p > 0.05). Six months of CPAP therapy resulted in significantly lower MPV values but increased values of PDW and RDW in patients with severe OSA (p = 0.001, p = 0.007, p = 0.001, respectively).

CONCLUSION

Our data suggest that complete blood count parameters in OSA patients such as MPV, PDW and RDW change significantly after CPAP therapy.

Increased levels of small dense low-density lipoprotein cholesterol associated with hemorheological abnormalities in untreated, early-stage essential hypertensives

Among subfractions of low-density lipoprotein cholesterol (LDL-C), small dense LDL-C (SdLDL-C) has been highlighted as the most atherogenic lipoprotein cholesterol. The present study aimed to compare the relationship of SdLDL-C with blood viscosity, a surrogate marker for cardiovascular disease, with that of other lipid fractions with blood viscosity in essential hypertensives (EHTs). In 128 untreated, early-stage EHTs, blood viscosity was measured with a falling-ball microviscometer, and serum levels of lipid fractions were determined. Blood and plasma viscosity was significantly higher in 49 patients with dyslipidemia (fasting serum level of LDL-C > 140 mg dl(-1), triglyceride > 150 mg dl(-1) or high-density lipoprotein cholesterol (HDL-C) < 40 mg dl(-1)) compared with 79 patients without dyslipidemia, although hematocrit and RBC rigidity index 'k' did not differ between the two groups. Together, SdLDL-C, LDL-C, triglyceride and large LDL-C were positively correlated with blood viscosity, but for HDL-C, the correlation was negative. After adjusting for non-lipid variables that correlated with blood viscosity (that is, the age, body mass index, resting diastolic blood pressure, sex, hematocrit, plasma viscosity and homeostasis model of assessment of insulin resistance), SdLDL-C was most strongly associated with blood viscosity among the lipid fractions. These data suggest that SdLDL-C could strongly increase blood viscosity in EHTs.