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The article discusses several science-related research published in "Science" and other journals as of September 2022. Topics include the benefits of forestation of global drylands in reducing global warming, the penetration of plume into the stratosphere following the violent eruption of the submarine volcano Hunga Tonga-Hunga Ha'apai in January of 2022, and early detection of cancer using a method which is based on analyzing tumor-derived RNA in platelets.

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Introduction: Simple indices derived from a blood count are useful as predictors of survival in both solid and hematological tumors. However, these indices have not been studied in human immunodeficiency virus (HIV)-associated non-Hodgkin's lymphoma (NHL). The present study evaluates whether there are differences in the survival of such patients at two years according to baseline values of mean platelet volume (MPV) and neutrophil-to-lymphocyte ratio (NLR). Material and methods: A retrospective cohort of patients between 2003 and 2018 with HIV and a confirmed diagnosis of some variant of nNHL at the Hospital Universitario San Ignacio, Bogotá, Colombia, was evaluated. 2-year survival was analyzed by comparing groups according to baseline values of MPV and NLR using Kaplan-Meier curves and log rank test. Cox regression model was used to control for confounding factors. Results: 31 patients were included. The combined follow-up time was 602 months. Ten patients died during follow-up. The 2-year survival was lower for patients with MPV >7.5 fL (41.6 vs. 84.0%, p =0.01, log rank test: 0.0057) and NLR >4.35 (33.0% vs. 76.0%, p =0.04; log rank test 0.028). Mortality was higher in patients with MPV >7.5 fL (HR 6.39; confidence interval 95% 1.35-30.21, p =0.015) controlling by the effect of type of lymphoma, International Prognostic Index and functionality. Conclusion: High values of MPV and NLR at the time of diagnosis of NHL are associated with mortality in patients with HIV infection. It is necessary to evaluate the utility of including these markers in prognostic indices. [ABSTRACT FROM AUTHOR]

AIM: This study aims to investigate whether there is a relationship between attention-deficit/hyperactivity disorder (ADHD) and inflammation, using hematologic inflammatory parameters in a large sample of children and adolescents. METHOD: This retrospective study comprises 347 children and adolescents with ADHD between 6 and 17 years of age who met the inclusion criteria as well as 205 healthy children and adolescents in the control group. Serum parameters such as white blood cell (WBC), neutrophil, lymphocyte, platelet, monocyte, eosinophil and basophil counts, mean platelet volume (MPV), and platelet distribution width (PDW) were recorded from complete blood count tests at the time of admission, while neutrophil lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), and other ratios were calculated based on these counts. RESULTS: NLR, PLR, MPV, PDW, WBC and neutrophil counts were significantly higher in children and adolescents with ADHD than in the control group. In the ADHD group, NLR, WBC and neutrophil counts were significantly higher in girls than in boys. CONCLUSIONS: The results of this study support the hypothesis that inflammation plays an important role in the complex pathophysiology of ADHD. In addition, our data confirm that easily obtainable and reliable hematological parameters can be used when investigating the role of inflammation in ADHD etiology. [ABSTRACT FROM AUTHOR]

Background: To the aim of this study was to evaluate the association between mean platelet volume (MPV) and diabetic retinopathy (DR). Methods: Patients with diabetes mellitus (DM) referred to Ophthalmology Clinic of Rohani Teaching Hospital in Babol, Northern Iran were entered into this case-control study. Healthy subjects in control group included individuals without history of DM. The patients were classified into four groups including I. Control (n=79), II. Diabetic patients without DR (n=68), III. Non-proliferative DR (n=61), and IV. Proliferative DR (n=64). Blood samples were collected, and necessary laboratory tests were performed. Results: The MPV value was significantly higher in each group of II, III and IV compared to group I (p<0.001). This value was also significantly higher in each group of III and IV compared to group II. On the other hand, there was no significant difference between III and IV groups in MPV. A significant correlation was found between MPV and fasting blood sugar in groups II (r=0.349, p=0.004), III (r=0.269, p=0.036) and IV (r=0.258, p=0.040). Moreover, there was a significant correlation between MPV and hemoglobin A1c in groups II (r=0.366, p=0.002), III (r=0.312, p=0.015) and IV (r=0.278, p=0.026). Conclusion: The results of this study showed that the increased MPV value was directly associated with DR and its severity. A positive association was also found between MPV and indicators of glycemic status. Considering that measurement of MPV as a suitable parameter reflecting platelet function can be easily conducted, it can be clinically used to monitor status of DR. [ABSTRACT FROM AUTHOR]

Background: Anxiety disorders are one of the most common psychiatric disorders existing in the population. The association between stress and platelet activity has been envisaged by the researchers. Mean platelet volume (MPV) is considered as the marker and determinant of platelet function. Objective: To evaluate the MPV in anxiety disorder and to check for the association of MPV with severity of anxiety. Method: This was a hospital-based, descriptive, cross-sectional casecontrol study. One hundred and fourteen consecutive anxiety disorder patients were included in the study. Age and gender matched 70 subjects were taken as controls. The Hamilton rating scale for anxiety (HAM-A) and the Hamilton rating scale for depression (HAM-D) were assessed and complete blood count, MPV, and lipid profile were measured for all the subjects. Results: MPV values were more in anxiety disorder (9.844±1.33) than in controls (8.72±0.49) and this difference was statistically significant (p<0.001). There was negative correlation between MPV and platelet count, and there was a positive correlation between HAM-A scores and MPV. Conclusion: Increased MPV is associated with anxiety disorder. Future research should be planned to investigate the effect of MPV, anxiety disorder on cardiovascular diseases and the effect of anxiety treatment on MPV. [ABSTRACT FROM AUTHOR]

Summary: Background: Atherosclerotic cardiovascular disease is a key cause of morbidity in non‐alcoholic fatty liver disease (NAFLD) but appropriate means to predict major acute cardiovascular events (MACE) are lacking. Aim: To design a bespoke cardiovascular risk score in NAFLD. Methods: A retrospective derivation (2008‐2016, 356 patients) and a prospective validation (2016‐ 2017, 111 patients) NAFLD cohort study was performed. Clinical and biochemical data were recorded at enrolment and mean platelet volume (MPV), Qrisk2 and Framingham scores were recorded one year prior to MACE (Cardiovascular death, acute coronary syndrome, stroke and transient ischaemic attack). Results: The derivation and validation cohorts were well‐matched, with MACE prevalence 12.6% and 12%, respectively. On univariate analysis, age, diabetes, advanced fibrosis, collagen proportionate area >5%, MPV and liver stiffness were associated with MACE. After multivariate analysis, age, diabetes and MPV remained independently predictive of MACE. The "NAFLD CV‐risk score" was generated using binary logistic regression: 0.06*(Age) + 0.963*(MPV) + 0.26*(DM1) – 16.44; 1Diabetes mellitus: 1: present; 2: absent. (AUROC 0.84). A cut‐off of −3.98 gave a sensitivity 97%, specificity 27%, PPV 16%, and NPV 99%. An MPV alone of >10.05 gave a sensitivity 97%, specificity 59%, PPV 24% and NPV 97% (AUROC 0.83). Validation cohort AUROCs were comparable at 0.77 (NAFLD CV‐risk) and 0.72 (MPV). In the full cohort, the NAFLD CV‐risk score and MPV outperformed both Qrisk2 and Framingham scores. Conclusions: The NAFLD CV risk score and MPV accurately predict 1‐year risk of MACE, thereby allowing better identification of patients that require optimisation of their cardiovascular risk profile. [ABSTRACT FROM AUTHOR]

Tinnitus is a perception disorder of sound. In addition to otologic diseases; mood disorders, inflammatory diseases, thromboembolic pathologies may lead to tinnitus. Mean platelet volume (MPV), Platelet Distribution Width (PDW) and Neutrophil-to-Lymphocyte Ratio (NLR) were investigated as biomarkers in tinnitus patients. In this study, we aimed to find whether there is any association between these biomarkers and bilateral tinnitus patients. Fifty eight with tinnitus and 58 healthy subjects were included to the study. The distribution of age and sex in each group were equal. Hearing thresholds of tinnitus patients were obtained with pure-tone audiometry. Hematologic values were evaluated in each group and correlation between these values and audiometric data were investigated in tinnitus patients. PDW values of the tinnitus group were found statistically significantly higher than those in control group (p=0.041). NLR was found lower in tinnitus patients and it was statistically significant (p=0.001). MPV values were found similar in each group. In tinnitus group there were no correlation between hematologic values and audiometric data. In this study, we found blood marker value alterations in bilateral tinnitus patients, but there was no correlation with audiologic data. And so we need larger studies to obtain more significant results. [ABSTRACT FROM AUTHOR]

Introduction: Ex vivo cell expansion under Good Manufacturing Practice (GMP) guidelines can be performed using medium additives containing human growth factors from platelets. These products can differently affect proliferation of adipose mesenchymal stromal stem cells (ASC). Qualification of medium additive performance is required for validation under GMP regulations: assessment of growth factor concentrations is not sufficient to predict the biological activity of the product batch. Proton nuclear magnetic resonance spectrometry (1H-NMR) and matrix-assisted laser desorption/ionization time of flight mass spectroscopy (MALDI-TOF MS) provide wide molecular characterization of samples. Aims: We aimed to assess if 1H-NMR and MALDI-TOF MS techniques can be used as quality control test potentially predicting the impact of a medium additive on cell proliferation. Methods: We tested the impact on ASC growth rate (cell proliferation assessment and cell morphology analysis) of four medium additives, obtained by different methods from human platelet apheresis product. In order to classify each medium additive, we evaluated growth factor concentrations and spectra obtained by 1H-NMR and by MALDI-TOF MS. Results: Medium additive obtained by CaCl2 activation of platelet rich products induced higher proliferation rate vs additive derived from platelet depleted ones. Additives obtained by freeze-and-thaw methods weakly induced ASC proliferation. As expected, principal component analysis of growth factor concentrations did not unravel specific biochemical features characterizing medium additives in relation with their biological activity. Otherwise, while 1H-NMR showed a partial resolution capacity, analysis of MALDI-TOF MS spectra allowed unambiguous distinction between the medium additives we used to differently stimulate cell growth in vitro. Discussion: MALDI-TOF and, despite limitations, 1H-NMR are promising cost effective and reliable quality controls to classify the potential of a medium additive to promote ASC growth. This can represent, after further investigations and appropriate validation, a significant advantage for GMP compliant manufacturing of advanced cell therapy products. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the reference range of blood plasma fibrinogen, which belongs to the group of moderate acute phase protein in rabbits. The experiment followed the dynamics of blood plasma fibrinogen (Fb) during the first year of life in 12 New Zealand White rabbits, 6 males and 6 females, starting at 1 month of age until the 7th month. It was shown that fibrinogen concentrations increased with the age. There was a statistically significant difference in Fb concentrations in rabbits at 3 (P<0.05), 6 (P<0.01) and 7 months of age (P<0.001) compared to levels obtained at 1 month of age in both genders. At ages of 1, 2 and 3 months, fibrinogen values were higher in male rabbits while in 7-month-old rabbits, plasma fibrinogen levels in females were significantly higher than those in male rabbits (P<0.01). [ABSTRACT FROM AUTHOR]

Abstract: Objective: Monitoring endogenous platelets during intravital microscopy often involves two approaches: fluorescently labeled antibodies or genetic models of platelet‐specific fluorescent protein expression. Due to limited data available on platelet functional changes induced by these methods, we compared functional effects of these methods on platelets. Methods: Platelet aggregation to collagen and thrombin, and collagen matrix‐mediated platelet adhesion/aggregation under flow were tested. We assessed platelets from mice expressing EYFP on platelets (Cre(+)), littermate controls (Cre(−)), C57BL/6 mice, and platelets from vehicle control and x‐488 treatment. We utilized intravital microscopy to monitor platelets in vivo using Cre(+) mice and x‐488 treatment. Results: Both genetic and antibody‐based approaches yielded substantial platelet‐specific fluorescence. Platelets from Cre(+) and Cre(−) mice behaved similarly in aggregation and adhesion/aggregation under flow. However, they exhibited significantly enhanced aggregation and higher adhesion/aggregation as compared to platelets from C57BL/6 mice. Compared to vehicle control, x‐488 platelet labeling did not induce significant functional changes in vitro. Both methods of platelet labeling provided satisfactory platelet detectability in vivo. Conclusions: x‐488 antibody labeling of platelets induced less alteration of platelet function than genetic approaches under our experimental conditions and seems more suitable for monitoring of endogenous platelets. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to asses the platelet activation in the acute phase of ischemic stroke and transient ischemic attack (TIA) by defining p-selectin (CD62) expression by flow cytometry in vivo - without stimulation with agonists. We also studied whether antiplatelet therapy supresses the levels of baseline p-selectin expression and verified if there is a correlation between platelet CD62 expression and the type of ischemic stroke. Methods: We determined the expression of platelet surface p-selectin using whole-blood flow cytometry within the first 48-hours after onset of cerebral symptoms in patients with atherothrombotic and lacunar ischemic stroke and in healthy volunteers. We studied the realationship between antiplatelet medication and the type of ischemic stroke to baseline p-selectin expression. Results: Patients with acute cerebral ischemia have an excess of circulating platelets that express p-selectin, compared to healthy volunteers. The difference between average p-selectin expression in the group of healthy volun teers and the group of patients with stroke was statistically significant (p-value < 0,000001). Patients with stroke without antiplatelet medication showed a higher p-selectin expression than patients with antiplatelet medi - cation (ASA, CLP, or ASA and CLP), hovewer, the difference was not statistically significant. There is no relationship between CD62 expression and the type of stroke. Conclusions: We can conclude that p-selectin is a highly sensitive blood biomarker of increased platelet activation. Antiplatelet therapy suppresses baseline p-selectin expression only minimally, insignificantly according to our results. [ABSTRACT FROM AUTHOR]

Background. The quality of platelet concentrates (PCs) is affected by preparation, storage, the type of container, and pathogen reduction technology (PRT). The Mirasol® Pathogen Reduction Technology (PRT) system (Terumo BCT Inc., Lakewood, USA), which uses riboflavin and ultraviolet (UV) light, has recently been proven effective against bacteria, viruses, parasites, and leukocytes. Objectives. The aim of the study was to evaluate the effect of the Mirasol® PRT system, based on riboflavin and UV light exposure, on the most common in vitro platelet quality parameters of PCs prepared from whole blood-derived buffy coats. Material and methods. The study included 15 trials (n = 15). For each trial, 2 PCs were used: 1 for treatment with the Mirasol® PRT system (M) and 1 for a control (C). In the M group, PCs were illuminated. In the C group, saline solution was added. PCs from groups M and C were stored at 20-24°C, with agitation. Samples were collected on days 1, 3 and 5 to determine platelet concentration, total platelet count/unit, mean platelet volume (MPV), power of hydrogen (pH), glucose and beta-thromboglobulin concentration (BTG), hypotonic shock response (HSR), aggregation, CD42b and CD62P expression, pCO2, and pO2. Results. No significant differences in HSR or CD42b expression were observed between groups M and C. All pH values were stable during the whole storage period (7.1-7.5). On storage day 1, CD62P expression in group C was significantly higher than in group M. In the Mirasol® group, significantly higher glucose consumption was noted on storage days 3 and 5. On day 5, a 2-3-fold increase in BTG was observed in both groups as compared to day 1; on day 5, BTG concentration was 32% higher in group M than in group C. On all storage days, pCO2 was comparable in groups M and C; lower pO2 values were reported for group M. Conclusions. In vitro results demonstrated that pH, HSR, aggregation, CD42b antigen expression, and MPV and platelet count parameters were comparable in groups M and C. [ABSTRACT FROM AUTHOR]

Portal hypertension secondary to liver cirrhosis may cause a number of life-threatening complications. The rupture of gastroesophageal varices is associated with a high mortality rate of 15‑30%. Hepatic venous pressure gradient (HVPG) is an accurate reflection of disease severity, however this can only be assessed via an invasive interventional procedure. The aim of the present study was to explore a non-invasive method based on 3D computed tomography (CT) volume rendering technology to accurately predict HVPG. A total of 77 patients diagnosed with liver cirrhosis underwent HVPG examination in the present study and the appropriate clinical and radiological data were retrospectively reviewed. A 3D liver and spleen volume rendering was constructed for volume measurements. All non-invasive parameters were tested using univariate analysis and the resulting variables that were statistically significant (P<0.20) were used in the multivariate linear regression model. The HVPG predictive model was as follows: HVPG = 18.726 ‑ 0.324 (albumin) + 1.57 (amino­transferase-to-platelet ratio index) + 0.004 (liver volume) (multivariate regression analysis, P=0.006). The corresponding area under receiver operating characteristic curve to identify clinically significant portal hypertension defined as HVPG ≥10 mmHg was 0.810 (95% confidence interval; 0.705‑0.891), with an optimal cut‑off value of 12.84, yielding a sensitivity of 80.36% a specificity of 76.19%. The results of the present study indicate that 3D CT volume rendering technology may have the potential to be used for non-invasive prediction of HVPG. [ABSTRACT FROM AUTHOR]

The primary biological function of platelets is to form hemostatic thrombi that prevent blood loss and maintain vascular integrity. These multi-responding cells are activated by different endogenous, physiological agonists due to the vast number of receptors present on the surface of the platelets. Collagen represents up to 40% of the total protein presented in the vessel wall and is the major activator of the platelets’ response after tissue injury, and is the only matrix protein which supports both platelet adhesion and complete activation. The aim of our study was to determine the effects of three major flavonolignans (silybin, silychristin and silydianin) on collagen-induced blood platelets’ activation, adhesion, aggregation and secretion of PF-4. We observed that depending on the dose, silychristin and silybin have anti-platelet properties observed as inhibition of collagen-induced activation (formation of blood platelet aggregates and microparticles, as well as decreased expression of P-selectin and activation of integrin α IIb β 3 ), aggregation, adhesion and secretion of PF-4. These effects highlight the potential of silybin and silychristin as supplementation to prevent primary and secondary thrombotic events wherein excessive blood platelet response to a physiological agonist is observed. [ABSTRACT FROM AUTHOR]

Background The platelet to lymphocyte ratio (PLR) has been found to predict clinical outcomes in multiple malignancies. The aim of this study was to assess the prognostic value of pretreatment PLR in biliary tract cancer (BTC). Methods We searched the MEDLINE, EMBASE, and Cochrane databases to identify studies evaluating the prognostic significance of pretreatment PLR in BTC. The end points were overall survival (OS), recurrence-free survival (RFS). Pooled hazard ratios (HRs) or odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using fixed-effects/random-effects models. Results A total of eleven studies comprising 2392 patients were included in the study. Pooled results showed that elevated PLR was significantly associated with decreased overall survival (HR: 1.59, 95% confidence interval [CI]: 1.42–1.78, p < 0.001) and recurrence-free survival (HR: 1.53, 95% CI: 1.16–2.00, p = 0.002). Subgroup analyses suggested that a high PLR predicted decreased OS in patient with BTC, regardless of sample size (< 200 or ≥ 200), treatment methods (surgery, mixed, or chemotherapy), tumor stage (mixed or metastatic), analysis methods (univariate or multivariate), cut-off values (< 150 or ≥ 150), and NOS score (< 7 or ≥ 7). Conclusions Elevated pretreatment PLR may be an unfavorable prognostic factor for clinical outcomes in patients with biliary tract cancer. [ABSTRACT FROM AUTHOR]

Background Febrile non-hemolytic transfusion reaction (FNHTR) is the most common type of transfusion reactions, and it could be reduced by transfusing patients with leukocyte-poor blood products. However, FNHTR still occur in certain patients transfused with leukocyte-poor red blood cell (LPR) products. It is examined whether human platelet antigen (HPA) could be a potential membrane antigen that plays a role in FNHTR. Methods A total of 120 inpatient subjects who transfused with LPR (60 in FNHTR group, 60 in control group) were typed for HPA-2, HPA-3, and HPA-15 using sequence specific primer-polymerase chain reaction (SSP-PCR) and electrophoresis. Results HPA-2 unmatched rate between donors and patients in FNHTR group was 18%, and only 3% unmatched rate was observed in control group ( p = 0.0082). FNHTR group was further classified according to the imputability. There was a significant difference ( p = 0.0041) between FNHTR (probable imputability, infection) group and control group, and more significant difference ( p = 0.0008) was seen between FNHTR (probable imputability, febrile neutropenia) group and control group. Conclusions Those results indicated that HPA-2 might play roles on inducing FNHTR in patients suffering from infectious diseases and febrile neutropenia. HPA-2 genotyping between donors and recipients might be worth integrating in pre-transfusion testing to increase transfusion safety. [ABSTRACT FROM AUTHOR]

Aims: Despite the involvement of the brain-derived neurotrophic factor (BDNF) in the physiopathology of major depressive disorder (MDD), the coherence between the components of the BDNF pathway and their link with the clinical features of MDD are insufficiently studied. We aimed to assess in Caucasian depressed patients the impact of the BDNF Val66Met polymorphism on plasma BDNF levels taking into account the clinical characteristics of MDD. Methods: A total of 328 Caucasian adult MDD patients with a current major depressive episode (MDE) were assessed for the BDNF Val- 66Met polymorphism, plasma BDNF levels and clinical characteristics of the MDD. Results: Plasma BDNF levels were linearly associated with the BDNF Val66Met genotypes (ValVal: 1,525.9 ± 1,183.3 pg/mL vs. ValMet: 1,248.7 ± 1,081.8 vs. MetMet: 1,004.9 ± 952.8; p = 0.04), Met carriers having lower BDNF levels than ValVal ones. Significant interactions between the Val66Met polymorphism and 3 clinical characteristics - age at onset (p = 0.03), MDD duration (p = 0.04), and number of previous MDE (p = 0.04) - were evidenced for plasma BDNF levels. Indeed, in Met carriers, but not in ValVal ones, plasma BDNF levels were negatively correlated with age at onset and positively correlated with MDD duration and number of previous MDE. Conclusion: Our results show a measurable, coherent, and functional BDNF pathway based on the BDNF Val66Met polymorphism and plasma BDNF levels in patients with a current MDE. This pathway is related to the clinical course of major depression, plasma BDNF levels being associated with the long-term history of MDD in Met carriers. Further studies assessing central BDNF are needed to understand the underlying mechanisms of this association. [ABSTRACT FROM AUTHOR]

Background: This study examines the clinical utility of the level of increased platelet distribution width (PDW) as a predictor of outcome in patients with traumatic brain injury. Methods: In this retrospective study, 120 patients with traumatic brain injury (TBI) were recruited. Age, gender, PDW, and Glasgow Coma Scale (GCS) scores were measured. These patients were divided into two groups based on their 30-day outcomes. Receiver operating curves (ROCs) were generated to identify predictors of 30-day mortality. Results: One hundred twenty patients with traumatic brain injury were enrolled in this study, 89 males (74.2%) and 31 females (25.8%) with a median age of 49.5 (19 - 89) years. The in-hospital mortality rate was 10.8% (n = 13). PDW levels in non-surviving patients were higher than in surviving patients. The higher the PDW, the lower the GSC score. The area under the curve (AUC) for PDW levels with regard to predicting 30-day mortality was 0.88 (95% confidence interval (CI), 0.78 to 0.97; p < 0.001). There was correlation between PDW level and GCS score (r = -0.30, 95% confidence interval (CI), - 0.46 to - 0.13; p < 0.001). Conclusions: PDW levels were associated with injury severity and mortality in patients with severe TBI. [ABSTRACT FROM AUTHOR]

Background Centrifugation of blood samples is an essential preanalytical step in the clinical biochemistry laboratory. Centrifugation settings are often altered to optimize sample flow and turnaround time. Few studies have addressed the effect of altering centrifugation settings on analytical quality, and almost all studies have been done using collection tubes with gel separator. Methods In this study, we compared a centrifugation time of 5 min at 3000 ×  g to a standard protocol of 10 min at 2200 ×  g. Nine selected general chemistry and immunochemistry analytes and interference indices were studied in lithium heparin plasma tubes and serum tubes without gel separator. Results were evaluated using mean bias, difference plots and coefficient of variation, compared with maximum allowable bias and coefficient of variation used in laboratory routine quality control. Results For all analytes except lactate dehydrogenase, the results were within the predefined acceptance criteria, indicating that the analytical quality was not compromised. Lactate dehydrogenase showed higher values after centrifugation for 5 min at 3000 ×  g, mean bias was 6.3 ± 2.2% and the coefficient of variation was 5%. Conclusions We found that a centrifugation protocol of 5 min at 3000 ×  g can be used for the general chemistry and immunochemistry analytes studied, with the possible exception of lactate dehydrogenase, which requires further assessment. [ABSTRACT FROM AUTHOR]

Rituximab is an effective therapy resulting in a platelet count improvement in 60% of patients with immune thrombocytopenia ( ITP). Rituximab depletes B cells; thus, a reduction in platelet autoantibody levels would be anticipated in patients who achieve a clinical response to this treatment. The objectives of this study were to determine whether rituximab was associated with a reduction in platelet autoantibody levels, and to correlate the loss of autoantibodies with the achievement of a treatment response. We performed a case-control study nested within a previous randomized controlled trial of standard therapy plus adjuvant rituximab or placebo. We measured platelet-bound anti-glycoprotein ( GP) IIb IIIa and anti- GPIb IX using the antigen capture test. Of 55 evaluable patients, 25 (45%) had a detectable platelet autoantibody at baseline. Rituximab was associated with a significant reduction in anti- GPIIb IIIa levels ( P = 0·02) but not anti- GPIb IX levels ( P = 0·51) compared with placebo. Neither the presence of an autoantibody at baseline nor the loss of the autoantibody after treatment was associated with a response to rituximab. The subset of patients with persistent autoantibodies after treatment failed to achieve a platelet count response, suggesting that persistence of platelet autoantibodies can be a marker of disease severity. [ABSTRACT FROM AUTHOR]

Background Mean platelet volume ( MPV) was proved to be a reliable prognostic factor in cardiac patients. However, platelet distribution width ( PDW) was disclosed to be more specific marker of platelet reactivity. The aim of study was to evaluate whether baseline PDW value can predict the outcome in patients undergoing percutaneous coronary interventions ( PCI) with drug-eluting stent implantation within coronary bifurcation lesions. Materials and methods It was a two-centre observational study, which included patients who underwent PCI within bifurcation lesions between January 2014 and December 2014. Thrombocytopenia below 100 000/μL and STEMI were the exclusion criteria. Analysed data came entirely from in-hospital records and information obtained from the 12-month telephone follow-up. Results We included 269 patients. Mean PDW value was 13·4 ± 2·5 fL, whereas median was 13 (Q1 < 11·6 fL, Q2 11·6-13 fL, Q3 13-14·8 fL and Q4 > 14·8 fL). We found strong correlation between PDW and MPV ( r = 0·96, P < 0·001), but no correlation was revealed between red blood cell distribution width ( RDW) and PDW ( r = 0·003, P = 0·95) as well as RDW and MPV ( r = 0·0018, P = 0·98). Receiver operating characteristics ( ROC) curve showed that PDW for cutoff 15·8% can predict MACE rate with sensitivity of 79% and specificity of 47% (area under curve - AUC 0·654; P = 0·01). A ROC curve for PDW categorized by 1-year TLR rate was described by optimal cutoff 16·3%, with sensitivity 69% and specificity 54% ( AUC 0·697; P = 0·0015). Conclusions PDW is an affordable and reliable predictor of 1-year MACE and TLR rate after PCI within coronary bifurcation lesions. [ABSTRACT FROM AUTHOR]

Background This study was aimed to define the short- and medium-term biological variation (BV) estimates, the index of individuality and the reference change value (RCV) of platelet count, platelet distribution width, mean platelet volume, platelet larger cell ratio, plateletcrit and immature platelet fraction. Methods The study population consisted of 43 health subjects, who participated to the assessment of medium-term (21 subjects; blood sampling once a week for 5 consecutive weeks) and short-term (22 subjects; blood sampling once a day for 5 consecutive days) BV study, using Sysmex XN-module. Eight subjects were also scheduled to participate to both phases. The data were subject to outlier analysis prior to CV-ANOVA, to determine the BV estimates with the relative confidence intervals. Results The medium-term and short-term within-subject BV (CV I ) was comprised between 2.3 and 7.0% and 1.1–8.6%, whereas the medium-term and short-term between-subjects BV (CV G ) was comprised between 7.1 and 20.7% and 6.8–48.6%. The index of individuality and index of heterogeneity were always respectively < 0.6 and > 0.63 for all the parameters, in both arms of the study. The RCVs were similar for all parameters, in both arms of the study. Conclusion This study allowed to define the BV estimates of many platelet parameters, some of them unavailable in literature. The kinetics of platelet turnover suggests the use of short-term BV data for calculating analytical goals and RCV. The correct clinical interpretation of platelet parameters also necessitates that each laboratory estimates local RCV values. [ABSTRACT FROM AUTHOR]

Introduction: Diabetes mellitus (DM) is a metabolic disorder associated with both microvascular and macrovascular complications. Mean platelet volume (MPV) is a marker of platelet activity, which plays a major role in the development of vascular complications of DM. The aim of this study is to compare the MPV levels before and after the decrease of glycated hemoglobin (HbA1c) levels in a large diabetic population.Material and Methods: This was a retrospective study conducted on type 2 diabetic patients from the outpatient clinic for 1 year between 2014 and 2015 with the participation of 595 diabetic patients.Results: When we compared the basal and post-treatment values, a significant decrease of MPV and HbA1c levels was found (HbA1c: 9.41 ±1.98% vs. 7.43 ±1.29%, p < 0.001; MPV: 9.11 ±1.42 vs. 8.17 ±1.04, p < 0.001). There was also a positive correlation between the mean changes of MPV and HbA1c levels after the treatment (ΔMPV: 0.93 ±0.96 vs. ΔHbA1c: 1.96 ±1.43; p = 0.005, r = 0.115). When the participants were divided into two groups according to their basal HbA1c levels (group A: HbA1c ≤ 6.5% and group B: HbA1c > 6.5%), it was clearly seen that improvement of glucose levels led to a significant decrease in MPV levels in both groups.Conclusions: The results of this study show that better glycemic control is associated with a significant decrease of MPV levels, regardless of whether the treatment modality is insulin or oral antidiabetic. [ABSTRACT FROM AUTHOR]

Background Diverse variables are involved in apheresis platelet collection, processing and storage. This survey shows how these are realized in Spain. Method An analysis of collected data was performed in a questionnaire completed by ten Transfusion Centers (TC) which perform between 50 and 520 apheresis procedures per month. This information comprises the procedures used to collect, inspect and store apheresis platelet concentrates (PC), and quality control data. Results Macroscopic inspection of PC is performed in all TC, especially during the first few hours post-collection and before distribution. The type of processor, duration of post-collection resting periods and temperature from the time of collection until distribution are similar in all TC. In 80% of TC, PC with small and scarce aggregates are distributed to transfusion services. The presence of clumps is influenced by type of processor, female donor, cold ambient temperature and collection of hyperconcentrated platelets, and is often recurrent in the same donor, although some TC have not found any influential variables. Overall, no objective inspection methods are followed, although there are exceptions. The degree of compliance with quality control parameters, such as the number of units studied, mean platelet yield, residual leukocyte counts and pH at expiry date, is acceptable in all TC. Compliance in terms of number of microbiological culture samples is variable. Discussion The usual practice in Spanish TC with respect to the collection, post-collection handling and storage of apheresis PC can be considered uniform, although some specific aspects of analyses should follow more objective methods. [ABSTRACT FROM AUTHOR]

A new RP-HPLC method for the quantitative determination of tinidazole in albino rat plasma was developed and validated as per US-FDA guidelines. The drug was spiked in the albino rat plasma and extracted with mobile phase by precipitation method. The extracted analyte was injected into Hypersil ODS C18 (4.6 × 150 mm; 5 μm) or equivalent, maintained at 25°C temperature and effluent monitored at 310 nm. The mobile phase consisted of potassium dihydrogen phosphate [pH 3.0]: acetonitrile [HPLC Grade] (40:60 v/v). The flow rate was maintained at 1.0 mL/min. The developed method shows high specificity for tinidazole. The calibration curve for tinidazole was linear from 1.0 to 40.0 ng/0.5mL plasma (r2= 1). The inter-day and intra-day precision was found to be within limits. The average % recovery for the drug tinidazole was found to be 99.53-100.21 % and the reproducibility was found to be satisfactory. The proposed method was adequate, sensitivity, reproducibility, and specificity for the determination of tinidazole in albino rat plasma. [ABSTRACT FROM AUTHOR]

The author reflects on the research report titled "Bacterial screening of platelet components by National Health Service Blood and Transplant, an effective risk reduction measure?," by C. McDonald and colleagues. Topics include the reduction of risk of septic transfusion reaction from platelets (PLTs), contamination of apheresis platelets (APs), and clinical impact of large-volume culture procedure to make PLTs.

BACKGROUND: Mean platelet volume (MPV), platelet distribution width (PDW) and P-LCR (platelet large cell ratio) are known platelet volume indices (PVI). Currently, the platelet volume indices (PVI) have emerged to determine its value as biomarker of liver fibrosis. OBJECTIVES: The present study determined the Platelet volume indices (PVI) as non invasive physiological marker of liver fibrosis in chronic hepatitis C patients. STUDY DESIGN: Case control study. STUDY SETTINGS: Department of Gastroenterology, ISRA University Hospital and Asian Institute of Medical Sciences (AIMS) Hyderabad from May-December 2014. SUBJECTS AND METHODS: A sample of 64 patients; 32 controls and 32 chronic hepatitis C cases were studied. Subjects were selected by non-probability (purposive) sampling as per inclusion and exclusion criteria. Roche Hitachi Hematolyzer was used for platelet count and platelet volume indices. Liver fibrosis was determined from liver biopsies by METAVIR Score. Data was analysed on Statistix 10.0 (USA) at 95% confidence interval (P<0.05). RESULTS: The PVI (MPV, PDW and P-LCR) and platelet count were raised in cases compared to controls (p<0.05). PVI showed major differences for METAVIR SCORE F0 -F4 of liver fibrosis (p<0.05). MPV, PDW and P-LCR showed positive correlation (r= 0.93, r= 0.80 and r= 0.75) with METAVIR (p <0.0001) respectively. CONCLUSION: The Platelet volume indices may be used as non-invasive physiological markers for liver fibrosis in chronic hepatitis C patients instead of invasive technique of liver biopsy. [ABSTRACT FROM AUTHOR]

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Background: Abdominal obesity is strongly correlated with cardiovascular risk and associated with platelet hyperactivity. This hyperactivity is associated with an increase in mean platelet volume (MPV). Few data are available about changes in platelet counts and MPV in obese patients after bariatric surgery (BS). The purpose of this study was to describe quantitative and qualitative changes in the platelet lineage after BS. Methods: One hundred twenty-eight consecutive patients were included. The mean age was 43 ± 12 years, 77 % of patients were female, and the mean preoperative BMI was 44 ± 6 kg/m. Ninety patients (71 %) had a Roux-en-Y gastric bypass (RYGBP), and 38 (29 %) had a sleeve gastrectomy (SG). Patients were evaluated preoperatively, and postoperative follow-up was performed at 3, 6, and 12 months. The postoperative evaluation included blood samples for full blood count (FBC), including measure of mean platelet volume (MPV). Results: At the 12-month follow-up, the reduction in preoperative weight was 29 ± 9 %. We showed a significant decrease in platelet count (245 ± 62 vs. 234 ± 54 G/L; p = 0.0015) found in parallel with a non-significant decrease in MPV (9.27 ± 1.1 vs. 9.22 ± 1.05; p = 0.34). With regard to the intervention type, SG caused a more significant decrease in platelet count than RYGBP ( p = 0.02). There was no significant difference in MPV variations between the two groups ( p = 0.08). Conclusions: Our results suggest that BS has a positive impact on platelet metabolism, possibly mediated by weight loss. These data need to be confirmed to understand the multifactorial benefits of BS on cardiovascular risk in obese patients. [ABSTRACT FROM AUTHOR]

Objective To evaluate the effects of a 6% hydroxyethyl starch (130/0.42) solution in either a buffered, electrolyte-balanced (HES-BAL), or a saline (HES-SAL) carrier solution on canine platelet function and whole blood coagulation. Design Prospective, randomized study. Setting University teaching hospital. Animals Thirty-seven client-owned dogs undergoing general anesthesia for arthroscopy or imaging studies. Interventions Dogs received a 15 mL/kg intravenous bolus of HES-SAL ( n = 13), HES-BAL ( n = 14), or a modified Ringer's solution ( n = 10) over 30-40 minutes. Coagulation was analyzed using a Platelet Function Analyzer-100 (closure time [CtPFA]), and whole blood thromboelastometry (ROTEM) with extrinsically (ex-tem and fib-tem) and intrinsically (in-tem) activated assays, which assessed clotting time (CT), clot formation time (CFT), maximal clot firmness (MCF), and lysis index (LI). Coagulation samples were assayed prior to fluid administration (T0), and 5 minutes (T1), and 3 hours (T2) following fluid bolus administration, respectively. Results Both HES solutions resulted in impaired platelet function as indicated by a significant prolongation of CtPFA at T1 as compared to T0, but which resolved by T2. An IV bolus of Ringer's solution did not alter platelet function. In both HES groups, whole blood coagulation was significantly impaired at T1 as indicated by a significant increase in in-tem CFT, and a significant decrease in ex-tem, in-tem, and fib-tem MCF compared to T0. Furthermore, a significant increase in ex-tem CFT at T1 compared to T0 was found in the HES-SAL group. With the exception of in-tem MCF after HES-BAL, these effects were not present at T2. No significant differences were found in CtPFA or any ROTEM variable at any time point between HES-SAL and HES-BAL. Conclusion Administration of a single bolus of 15 mL/kg 6% HES 130/0.42 results in significant but short-lived impairment of canine platelet function and whole blood coagulation, regardless of carrier solution. [ABSTRACT FROM AUTHOR]

Objective: To determine the frequency of Von Willebrand disease (vWD) in patients of heavy menstrual bleeding (HMB). Study Design: Hospital based cross sectional study. Place and Duration of Study: Study was conducted at the Gynecology and Obstetrics department, Military Hospital, Rawalpindi in collaboration with Haematology Department of Armed Forces Institute of Pathology (AFIP) Rawalpindi, from Jul to Dec 2015. Material and Methods: Women presenting with HMB were enrolled in the study after informed consent. HMB was defined as cyclical bleeding at normal intervals but patient is using more than 5 pads per day or increase in duration 8/28 or more for at least last 06 months. Venous blood samples were taken and screened for the hemoglobin level (Hb), platelet count, prothrombin time (PT), activated partial thromboplastin time (aPTT) and Von Willebrand antigen (vWF:Ag) in addition to bleeding time (BT) at the Armed Forces Institute of Pathology (AFIP). The demographic details (age, age at menarche), clinical features (menstrual history, quantity of bleeding) and laboratory findings were recorded on the study proforma. Results: A total of 200 patients were enrolled in this study with mean age of 32.3 ± 8.5 years. Mean flow of menstrual blood was 9.8 ± 2.5 pads / day. Mean Hb% was 8.1 ± 1.4 g/dl. Twenty nine (14.5%) patients were having low level of vWF:Ag. Conclusion: There is high frequency of von Willebrand disease among females presenting with heavy menstrual bleeding in our set up. Therefore all patients with heavy menstrual bleeding except those with obvious causes like multiple fibroid should be screened for von Willebrand disease. [ABSTRACT FROM AUTHOR]

Fatty acids, which are well-known for their influence on human metabolism and signal transduction, are also a substantial component of cellular membranes and regulate the basic properties and functions of membranes. Owing to their multiple functions, fatty acid profiles of cell membranes are of great interest to those who are studying the relationship between membrane biochemical compositions and functions. A HCl-catalyzed derivation method and a gas chromatography with mass spectrometry analysis method were developed to accurately profile the fatty acids in cell membranes of erythrocytes, leukocytes, and platelets. The detection limits of all 35 fatty acids ranged from 0.58 to 22 ng/mL and the limits of quantitation were between 2.1 and 72 ng/mL. Finally, the established method was used to profile the membrane fatty acids of 44 healthy volunteers from the north and south of China. Results revealed significant differences in the fatty acid profiles from the two regions, particularly those of the erythrocytes. This technique may be applied to cell membrane studies to generate new biological hypotheses concerning fatty acid composition and membrane functions as well as to construct related disease profiles. [ABSTRACT FROM AUTHOR]

Background: Bacterial contamination of platelet concentrates (PCs) remains a serious problem in transfusion. We have been conducting sterility tests on all PCs rejected by blood centers or hospitals due to abnormal appearances. We recently experienced a case in which discrepant results were obtained between the methods used to identify a bacterial species isolated from a PC, requiring further analyses.Study Design and Methods: Bacteria were isolated from a PC using the BacT/ALERT system and plate culture. The species was identified using biochemical tests and molecular analysis. Phylogenetic trees were constructed using sequences of the 16S ribosomal RNA (rRNA) and superoxide dismutase (sodA) genes from the bacterial isolate and related species. In addition, the isolate was cultured at temperatures of 10°C and below to determine its growth activity at low temperatures.Results: Biochemical tests determined that the isolate was Streptococcus alactolyticus, whereas molecular analysis determined that it was Lactococcus garvieae. These two species belonged to different clusters on the phylogenetic tree. Similar to L. garvieae, the isolate could grow at 10°C.Conclusions: We conclude that the isolate was L. garvieae according to molecular identification and its growth characteristic at 10°C. Molecular analysis enabled the identification of this species, which was difficult to classify by biochemical tests. Blood facilities need to be prepared with multiple techniques, including genetic analysis techniques, for identifying contaminating bacterial species. L. garvieae can grow at 10°C and can contaminate both red blood cell concentrates and PCs; thus, this species should be listed as a cryophilic bacterium that could threaten blood safety. [ABSTRACT FROM AUTHOR]

The article discusses the findings on the cellular development of blood patelets. It mentions the role of microarray technology in gene-expression research, hematopoietic stem, progenitor, and mature cell populations. It also mentions the information on megakaryocyte development along with the use of bioinformatics in the research.

Platelets are small corpuscular elements, which play an essential role in hemostasis and thrombosis. As active players in the thrombotic process, hyperactive platelets are involved in the pathogenesis of cardiovascular disorders. Nevertheless, the role of platelet size, as a biologicalmarker of platelet activation, remains debated in the setting of venous thrombosis. Therefore, we conducted a retrospective case-control study to clarify the potential association between mean platelet volume (MPV) and newly diagnosed venous thromboembolism (VTE) by reviewing data of all consecutive patients receiving a diagnosis of VTE at the emergency department (ED) of the University Hospital of Parma (Italy) between January and December, 2014. The control population was represented by outpatients undergoing routine laboratory testing for health checkup at the phlebotomy center of the same University Hospital during the same period. MPV was found to be comparatively decreased in the entire cohort of patients with VTE compared with the outpatient population, as well as in those with isolated deep vein thrombosis (DVT) or pulmonary embolism (PE). A decreased MPV value (i.e., < 10.8 fL) was found to be associated with an increased risk of diagnosing VTE (relative risk, 1.18; 95% CI, 1.09-1.28; p < 0.001), as well as of diagnosing isolated DVT (relative risk, 1.19; 95% CI, 1.07-1.31; p = 0.001) and isolated PE (relative risk, 1.17; 95% CI, 1.04-1.30; p = 0.007). A decreased MPV value in active cancer patients was associated with the highest risk of diagnosing thrombosis (relative risk, 1.29; 95% CI, 1.10-1.51; p = 0.002). These results support an inverse association between MPV and the risk of venous thrombosis at diagnosis. [ABSTRACT FROM AUTHOR]

Size of membrane microparticles (MPs) from blood plasma and MPs produced in vitro by activated endothelial cells (ECs), monocytes, THP-1 monocytic cells, granulocytes, and platelets was evaluated by dynamic light scattering. MPs were sedimented from the culture media, cell supernatants, and plasma at 20 000 g for 30 min. Average diameters of all types of MPs ranged from 300 to 600 nm. Plasma MPs had the smallest size. Close sizes were registered for MPs from platelets and THP-1 cells. MPs from monocytes were larger, and MPs from granulocytes and ECs were the largest ones. The data obtained indicate that the size of membrane MPs depends on the type of their cell-producers. [ABSTRACT FROM AUTHOR]

Background Pseudothrombocytopenia secondary to platelet clumping is a common cause of preanalytic error for platelet counts in dogs, cats, and horses. In human beings, it is suggested that prewarming blood samples to 37°C prior to hematology analysis will reduce platelet clumping. Objectives The purpose of the study was to evaluate the effect of prewarming EDTA blood samples to 37°C on measured platelet counts and other hematologic variables. Methods The EDTA blood samples from dogs, cats and horses submitted to the clinical pathology laboratory at the University of Cambridge were included. Complete blood cell counts performed using a Sysmex XT-2000iV hematology analyzer were done on samples at room temperature (approximately 22°C) and following warming of the samples to 37°C in a water bath. The Wilcoxon signed rank test was used to compare hematologic variables, including platelet count, before and after sample warming to 37°C. Data are presented as median (25th, 75th percentile) increase. Results Blood samples from 39 dogs, 19 cats, and 10 horses were included. Sample warming to 37°C resulted in a statistically significant increase in platelet counts in dogs (11 [−2, 30] ×109/L), cats (36 [14, 84] ×109/L), and horses (42 [31, 79] ×109/L). Sample warming did not significantly affect other hematologic variables. Conclusions Prewarming EDTA blood samples to 37°C prior to hematologic analysis increased platelet counts overall in canine, feline, and equine blood, but did not abrogate platelet clumping and pseudothrombocytopenia fully in some cases. Furthermore, true pseudothrombocytopenia was not confirmed in these animals. [ABSTRACT FROM AUTHOR]

Background and objectives Extent of shape change ( ESC), hypotonic shock response ( HSR), the adhesive glycoprotein CD62P and lactate have been widely used as in vitro quality makers of platelet concentrates. Our aim was to evaluate soluble glycoprotein V ( sGPV) as a platelet in vitro activation marker for platelet concentrates. Data were obtained from different validations during a twelve-year period. Materials and methods Platelet concentrates stored in PAS B, PAS E with 20-35% plasma carry-over or in plasma were prepared either from buffy coats or collected by apheresis. The samples were analysed up to day seven using sGPV, ESC, HSR, CD62P and lactate in addition to normal quality control assays. Results sGPV correlated statistically significantly with ESC, HSR, CD62P and lactate in platelet concentrates stored in PASs. Conclusion We propose that quantitative sGPV which is calculated per platelet number could be used as the first choice in vitro platelet activation marker in validations and monitoring platelet production processes. sGPV could also be a promising alternative to platelet activation assays used in interlaboratory comparisons of the quality of platelet concentrates. Quantitative lactate and lactate production rate can be used to evaluate the quality of platelets concentrates during storage. However, the formation of lactate depends on the platelet count and the amount of glucose in the product making the comparison more difficult. [ABSTRACT FROM AUTHOR]

Background: Bone marrow examination may be required to discriminate causes of thrombocytopenia as hypoproductive or hyperdestructive. However, this procedure is invasive and time consuming. This study assessed the diagnostic value of Mean Platelet Volume (MPV), Platelet Distribution Width (PDW) and Platelet Large Cell-Ratio (P-LCR) in discriminating causes of thrombocytopenia as hypoproductive or hyperdestructive (Immune thrombocytopenia purpura). Method: A prospective cross-sectional study was conducted on 83 thrombocytopenic patients (Plt < 150 × 109/L). From these, 50 patients had hypoproductive and the rest 33 Immune Thrombocytopenia Purpura (ITP). Age and sex matched 42 healthy controls were included as a comparative group. Hematological analysis was carried out using Sysmex XT 2000i 5 part diff analyzer. SPSS Version16 was used for data analysis. A two by two table and receiver operating characteristic (ROC) curve was used to calculate sensitivity, specificity, positive and negative predictive values, for a given platelet indices (MPV, PDW and P-LCR). Student t test and Mann Whitney U test were used to compare means and medians, respectively. Correlation test was used to determine associations between continuous variables. Results: All Platelet indices were significantly higher in ITP patients (n = 33) than in hypoproductive thrombocytopenic patients (n = 50) (p < 0.0001). In particular MPV and P-LCR have larger area under ROC curve (0.876 and 0.816, respectively), indicating a better predictive capacity, sensitivity and specificity in discriminating the two causes of thrombocytopenia. The indices were still significantly higher in ITP patients compared to 42 healthy controls (p < 0.0001). A significant negative correlation was observed between platelet count and platelet indices in ITP patients, (p < 0.001). Conclusion: MPV, PDW and P-LCR help in predicting thrombocytopenic patients as having ITP or hypoproductive thrombocytopenia. If these indices are used in line with other laboratory and clinical information, they may help in delaying/ avoiding unnecessary bone marrow aspiration in ITP patients or supplement a request for bone morrow aspiration or biopsy in hypoproductive thrombocytopenic patients. [ABSTRACT FROM AUTHOR]

Platelet indices (PI) - plateletcrit, mean platelet volume (MPV) and platelet distribution width (PDW) - are a group of derived platelet parameters obtained as a part of the automatic complete blood count. Emerging evidence suggests that PIs may have diagnostic and prognostic value in certain diseases. This study aimed to summarize the current scientific knowledge on the potential role of PIs as a diagnostic and prognostic marker in patients having emergency, non-traumatic abdominal surgery. In December 2015, we searched Medline/PubMed, Scopus and Google Scholar to identify all articles on PIs. Overall, considerable evidence suggests that PIs are altered with acute appendicitis. Although the role of PI in the differential diagnosis of acute abdomen remains uncertain, low MPV might be useful in acute appendicitis and acute mesenteric ischemia, with high MPV predicting poor prognosis in acute mesenteric ischemia. The current lack of consistency and technical standards in studies involving PIs should be regarded as a serious limitation to comparing these studies. Further large, multicentre prospective studies concurrently collecting data from different ethnicities and genders are needed before they can be used in routine clinical practice. [ABSTRACT FROM AUTHOR]

In recent years autologous platelet concentrates (APCs) have become popular in several medicine fields, representing a valuable adjunct to regenerative surgical procedures. Beneficial effects in the control of postsurgical discomfort and infection have also been frequently reported, suggesting that APC may possess anti-inflammatory and antimicrobial properties. The aim of the present review was to summarize the current evidence regarding the antimicrobial effects of platelet concentrates, investigated byin vitroand animal studies. This review was conducted following a systematic approach. An electronic search was performed on MEDLINE, EMBASE and Scopus databases using appropriate search terms, without language or time restrictions. Preclinical studies assessing the antimicrobial activity of APC were included and divided according to the experimental design. Twentyin vitrostudies and four animal studies, investigating APC effects on a broad range of microorganisms, were included. Inin vitrostudies APC reduced the growth of microorganisms during the first hours of incubation, while they could not completely break down the microbial load. In fact, over time a recovery of bacterial growth was always observed, suggesting that APCs display a bacteriostatic rather than a microbicidal activity. All animal studies showed that APC administered by local injections were able to reduce the infection caused by different microorganisms, although to a lesser extent compared to antibiotics. In conclusion, although the exact action mechanisms of interaction with microbial pathogens need further investigation, platelet concentrates proved to have antimicrobial properties, and therefore could represent a useful natural substance for controlling postoperative infections at surgical sites. [ABSTRACT FROM AUTHOR]

It has been demonstrated recently in several solid tumors that thrombocytosis at diagnosis may correlate with tumor invasion, metastatic progression and worse outcome. Several details of the pathomechanism of the relationship of thrombocytosis and cancer have been elucidated; however, the complete process is not clearly understood. Several hypotheses have been proposed. Recently, it was suggested that in ovarian cancer elevated IL-6 production by the tumor may induce increased megakaryopoiesis via hepatic thrombopoietin production leading to thrombocytosis. The importance of the prognostic power of elevated platelet count is still debated in gastrointestinal cancer. The aims of this review were to evaluate the prognostic significance of thrombocytosis in gastrointestinal tumors, to see whether clinical practice confirmed the hypotheses and to reveal the causes of the inconsistent findings. [ABSTRACT FROM AUTHOR]

Stromal cell-derived factor-1 (SDF-1), signaling through CXCR4, is implicated in megakaryopoiesis and platelet production. SDF-1 rs2297630 is a functional polymorphism in linkage disequilibrium with other functional variants in SDF-1. This study aimed to investigate the role of SDF-1 rs2297630 in chronic ITP. The genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism and confirmed by direct sequencing. Immature platelet fraction (IPF) was performed using Sysmex XE-2100. Anti-platelet autoantibodies were assayed by enzyme-linked immunosorbent assay. The main characteristics at diagnosis and the outcome of chronic ITP in 201 Chinese patients were retrospectively reviewed. There was no significant difference in either genotype or allelic distribution between ITP patients and the controls (p= 0.114;p= 0.787). However, both heterozygote (GA) and homozygote minor allele (AA) patients had significantly increased megakaryocyte quantity compared to homozygote genotype (GG) patients at diagnosis (p =0.011). The mean IPF values of GA and AA genotype patients were higher than those observed in the GG genotype patients when platelet counts ≤50 × 109/L at diagnosis (p= 0.007). Patients with GA and AA genotype showed a higher response rate to standard treatments than patients with GG genotype (p< 0.001). In particular, GA and AA genotype patients had a significantly increased chance of responding to steroids, intravenous immunoglobulin (IVIG), and thrombopoietin analogs (p= 0.007;p= 0.029;p= 0.034, respectively). No significant difference was found between anti-platelet antibodies and genotypes (p= 0.296). In summary, the SDF-1 rs2297630 was associated with platelet production and treatment response in Chinese patients with chronic ITP. [ABSTRACT FROM AUTHOR]

Background: Imbalance in hemostatic mechanisms can occur during pregnancy with a tendency for hypercoagulability and increased thrombosis risk. Pregnant women with hypertensive disorder, especially preeclampsia, show alterations in platelet indexes. Immature platelet fraction (IPF) has been suggested as a sensitive index for monitoring changes in platelet production and destruction.Objectives: To evaluate the IPF in patients diagnosed with a gestational hypertensive disorder (GHD).Patients and methods: A cross-sectional study was conducted at an University Hospital to estimate maternal blood IPF index in 99 pregnant women, divided into three groups: normotensive pregnancy (NP), preeclampsia syndrome (PES), and non-proteinuric hypertensive pregnancy (nPHP). Following ethical approval and written informed consent, samples were collected from 33 NP, 34 PES, and 32 nPHP women. Platelet indexes were measured by fluorescent flow cytometry.Results: IPF and mean platelet volume (MPV) counts in GHD were significantly higher than in NP (IPF: 3.8, 2.4–5.1%; 8.6, 5.8–10.6%; 7.3, 4.2–10.2%;p< 0.001 and MPV: 10.6 ± 0.9 fL; 12.1 ± 1.0 fL; 11.6 ± 1.0 fL;p< 0.001 for NP, PES, and nPHP, respectively). No difference was detected between PES and nPHP groups. The distribution of patients with an IPF above 6.1%for NP, PES, and nPHP was 9%, 65%, and 43.8%, respectively (p< 0.001). IPF as a test to differentiate GHD from the controls achieved an area under the curve of 0.83 on a receiver operating characteristics curve.Conclusion: A distinct profile in platelet indexes was detected in hypertensive pregnancies. It suggests that these markers could be used in daily routine as an additional tool in the management of pregnant women. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate whether rare missense genetic variants in several genes related to platelet functions and acetylsalicylic acid (ASA) response are associated with the platelet reactivity in patients with diabetes type 2 (T2D) on ASA therapy. Fifty eight exons and corresponding introns of eight selected genes, including PTGS1, PTGS2, TXBAS1, PTGIS, ADRA2A, ADRA2B, TXBA2R, and P2RY1 were re-sequenced in 230 DNA samples from T2D patients by using a pooled PCR amplification and next-generation sequencing by Illumina HiSeq2000. The observed non-synonymous variants were confirmed by individual genotyping of 384 DNA samples comprising of the individuals from the original discovery pools and additional verification cohort of 154 ASA-treated T2DM patients. The association between investigated phenotypes (ASA induced changes in platelets reactivity by PFA-100, VerifyNow and serum thromboxane B2 level [sTxB2]), and accumulation of rare missense variants (genetic burden) in investigated genes was tested using statistical collapsing tests. We identified a total of 35 exonic variants, including 3 common missense variants, 15 rare missense variants, and 17 synonymous variants in 8 investigated genes. The rare missense variants exhibited statistically significant difference in the accumulation pattern between a group of patients with increased and normal platelet reactivity based on PFA-100 assay. Our study suggests that genetic burden of the rare functional variants in eight genes may contribute to differences in the platelet reactivity measured with the PFA-100 assay in the T2DM patients treated with ASA. [ABSTRACT FROM AUTHOR]

Considerable evidence has been accumulated concerning the roles of platelets in immune responses. In the present study, we examined the functional modulation of macrophages by platelets. When mouse bone marrow-derived macrophages (BMDMs) were co-cultured with platelets, BMDMs produced lower levels of nitric oxide (NO), tumor necrosis factor-α (TNF)-α, and interleukin (IL)-6 in response to a bacterial endotoxin (LPS) and zymosan. The attenuation in the macrophage susceptibility to LPS appeared to be mediated by soluble factors secreted from platelets. The mRNA levels of NOS2 (iNOS), TNF-α, and IL-6 in LPS-stimulated BMDMs that had been cultured with a conditioned medium of platelets were also decreased as analyzed by RT-qPCR. The ability of the platelet-conditioned medium to suppress macrophage NO production was recovered in a high-molecular-weight fraction (>670 kDa) after gel-filtration chromatography on a Superose 6 column. These results suggest that platelets control the susceptibility of macrophages to prevent excessive responses to LPS and provide mechanistic insight into a previous report that experimental thrombocytopenia aggravated organ failure in LPS-induced endotoxemia. [ABSTRACT FROM AUTHOR]

Platelets are critical for maintaining vascular hemostasis, but also play a major role in the formation of occlusive cardiovascular and cerebrovascular thrombi under disease conditions. Secretion of platelet alpha and dense granules is a requirement for efficient thrombus formation. Understanding and targeting the mechanisms of secretion is important to aid the development of effective antithrombotics. SNAP29 is a tSNARE found in platelets, but whose role has not been defined. Using a platelet-specific SNAP29 knockout mouse model, we assessed the role of SNAP29 in platelet secretion and function under standardized conditions and also inin vitroandin vivothrombosis. The data showed no major defects in SNAP29-null platelets, but revealed a minor defect in α-granule secretion and a significant increase in embolization rate of thrombiin vivo. These data suggest that SNAP29 contributes to the regulation of platelet α-granule secretion and thrombus stability, possibly partially masked by functional redundancy with other tSNAREs, such as SNAP23. [ABSTRACT FROM AUTHOR]