Platelets in inflammation and immune modulations: functions beyond hemostasis

Restraint Stress-Induced Neutrophil Inflammation Contributes to Concurrent Gastrointestinal Injury in Mice

Psychological stress increases risk of gastrointestinal tract diseases. However, the mechanism behind stress-induced gastrointestinal injury is not well understood. The objective of our study is to elucidate the putative mechanism of stress-induced gastrointestinal injury and develop an intervention strategy. To achieve this, we employed the restraint stress mouse model, a well-established method to study the pathophysiological changes associated with psychological stress in mice. By orally administering gut-nonabsorbable Evans blue dye and monitoring its plasma levels, we were able to track the progression of gastrointestinal injury in live mice. Additionally, flow cytometry was utilized to assess the viability, death, and inflammatory status of splenic leukocytes, providing insights into the stress-induced impact on the innate immune system associated with stress-induced gastrointestinal injury. Our findings reveal that neutrophils represent the primary innate immune leukocyte lineage responsible for stress-induced inflammation. Splenic neutrophils exhibited elevated expression levels of the pro-inflammatory cytokine IL-1, cellular reactive oxygen species, mitochondrial burden, and cell death following stress challenge compared to other innate immune cells such as macrophages, monocytes, and dendritic cells. Regulated cell death analysis indicated that NETosis is the predominant stress-induced cell death response among other analyzed regulated cell death pathways. NETosis culminates in the formation and release of neutrophil extracellular traps, which play a crucial role in modulating inflammation by binding to pathogens. Treatment with the NETosis inhibitor GSK484 rescued stress-induced neutrophil extracellular trap release and gastrointestinal injury, highlighting the involvement of neutrophil extracellular traps in stress-induced gastrointestinal inflammation. Our results suggest that neutrophil NETosis could serve as a promising drug target for managing psychological stress-induced gastrointestinal injuries.

The genesis of cardiovascular risk in inflammatory arthritis: insights into glycocalyx shedding, endothelial dysfunction, and atherosclerosis initiation

This narrative review provides a comprehensive examination of the complex interplay between inflammatory arthritis (IA) and cardiovascular pathology. It particularly illuminates the roles of atherosclerosis initiation, endothelial dysfunction, and glycocalyx shedding. IA not only provokes tissue-specific inflammatory responses, but also engenders a considerable degree of non-specific systemic inflammation. This review underscores the accelerating influence of the chronic inflammatory milieu of IA on cardiovascular disease (CVD) progression. A focal point of our exploration is the critical function of the endothelial glycocalyx (EG) in this acceleration process, which possibly characterizes the earliest phases of atherosclerosis. We delve into the influence of inflammatory mediators on microtubule dynamics, EG modulation, immune cell migration and activation, and lipid dysregulation. We also illuminate the impact of microparticles and microRNA on endothelial function. Further, we elucidate the role of systemic inflammation and sheddases in EG degradation, the repercussions of complement activation, and the essential role of syndecans in preserving EG integrity. Our review provides insight into the complex and dynamic interface between systemic circulation and the endothelium.

Features of the response to subchronic low-dose exposure to copper oxide nanoparticles in rats

Copper is an essential trace element for human health and, at the same time, a major industrial metal widely used both in its elemental form and in compounds. We conducted a dose-dependent assessment of the response of outbred albino male rats to subchronic low-dose exposure to copper oxide nanoparticles administered intraperitoneally at cumulative doses of 18 and 36 mg/kg during 6 weeks to exposure groups 1 and 2, respectively. We observed disorders at different levels of organization of the body in the exposed animals, from molecular to organismal. The observed decrease in the activity of succinate dehydrogenase in nucleated blood cells gave evidence of impaired bioenergetics processes. In view of the results of the metabolomics analysis, we assume mitochondrial damage and contribution of apoptotic processes to the pathology induced by copper poisoning. We also assume neurodegenerative effects based on the assessed morphological parameters of the nervous system, results of behavioral tests, and a decreased level of expression of genes encoding NMDA receptor subunits in the hippocampus. The hepatotoxic effect noted by a number of metabolomics-based, biochemical, and cytological indicators was manifested by the impaired protein-synthesizing function of the liver and enhanced degenerative processes in its cells. We also observed a nephrotoxic effect of nanosized copper oxide with a predominant lesion of proximal kidney tubules. At the same time, both doses tested demonstrated such positive health effects as a statistically significant decrease in the activity of alkaline phosphatase and the nucleated blood cell DNA fragmentation factor. Judging by the changes observed, the cumulative dose of copper oxide nanoparticles of 18 mg/kg body weight administered intraperitoneally approximates the threshold one for rats. The established markers of health impairments may serve as a starting point in the development of techniques of early diagnosis of copper poisoning.

Clinical evaluation of autologous platelet-rich plasma therapy for intrauterine adhesions: a systematic review and meta-analysis

Objective

This meta-analysis aims to evaluate the efficacy and safety of autologous platelet-rich plasma (PRP) administration in reducing adhesion recurrence and improving pregnancy outcomes in patients with intrauterine adhesion (IUA).

Methods

We conducted a comprehensive search of Pubmed, Embase, the Cochrane Library, Web of Science, Scopus, and China National Knowledge Internet (CNKI) from inception to February 10, 2023, without any language or regional restrictions. We used random-effects models to assess odds ratios (OR) and weight mean differences (WMD) with 95% confidence intervals (CI).

Results

Our meta-analysis included a total of 730 patients from 10 clinical studies (6 RCTs and 4 non-RCTs). The results showed that PRP administration significantly increased endometrial thickness (WMD = 0.79, 95% CI: 0.40-1.19; P < 0.001; I² = 0.0%), menstrual volume (WMD = 2.96, 95% CI = 2.30-3.61; P < 0.001; I² = 0.0%), and days of menstruation (WMD = 1.13, 95% CI = 0.86-1.41; P < 0.001; I² = 0.0%). Additionally, the clinical pregnancy rate was also improved (OR = 1.82, 95% CI: 1.19-2.78; P = 0.006; I² = 0.0%). However, there was insufficient evidence to reach a conclusion regarding the effects of PRP on the recurrence rate of moderate to severe IUA, changes in AFS scores, miscarriage rate, and live birth rate.

Conclusions

Our analysis confirms that autologous PRP is an effective treatment for IUA. However, the limited sample size suggests that the results should be interpreted with caution. Therefore, larger and well-designed studies are necessary in the future to confirm these findings and explore the optimal PRP dosing regimens further.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO, identifier CRD42023391115.

The Role of Activating Transcription Factor 3 in Metformin's Alleviation of Gastrointestinal Injury Induced by Restraint Stress in Mice

Metformin is one of the most commonly used drugs for type 2 diabetes mellitus. In addition to its anti-diabetic property, evidence suggests more potential applications for metformin, such as antiaging, cellular protection, and anti-inflammation. Studies have reported that metformin activates pathways with anti-inflammatory effects, enhances the integrity of gut epithelial tight junctions, and promotes a healthy gut microbiome. These actions contribute to the protective effect of metformin against gastrointestinal (GI) tract injury. However, whether metformin plays a protective role in psychological-stress-associated GI tract injury remains elusive. We aim to elucidate the potential protective effect of metformin on the GI system and develop an effective intervention strategy to counteract GI injury induced by acute psychological stress. By monitoring the levels of GI-nonabsorbable Evans blue dye in the bloodstream, we assessed the progression of GI injury in live mice. Our findings demonstrate that the administration of metformin effectively mitigated GI leakage caused by psychological stress. The GI protective effect of metformin is more potent when used on wild-type mice than on activating-transcription-factor 3 (ATF3)-deficient (ATF3^-/-) mice. As such, metformin-mediated rescue was conducted in an ATF3-dependent manner. In addition, metformin-mediated protection is associated with the induction of stress-induced GI mRNA expressions of the stress-induced genes ATF3 and AMP-activated protein kinase. Furthermore, metformin treatment-mediated protection of CD326⁺ GI epithelial cells against stress-induced apoptotic cell death was observed in wild-type but not in ATF3^-/- mice. These results suggest that metformin plays a protective role in stress-induced GI injury and that ATF3 is an essential regulator for metformin-mediated rescue of stress-induced GI tract injury.

Effects of the interactions between platelets with other cells in tumor growth and progression

It has been confirmed that platelets play a key role in tumorigenesis. Tumor-activated platelets can recruit blood cells and immune cells to migrate, establish an inflammatory tumor microenvironment at the sites of primary and metastatic tumors. On the other hand, they can also promote the differentiation of mesenchymal cells, which can accelerate the proliferation, genesis and migration of blood vessels. The role of platelets in tumors has been well studied. However, a growing number of studies suggest that interactions between platelets and immune cells (e.g., dendritic cells, natural killer cells, monocytes, and red blood cells) also play an important role in tumorigenesis and tumor development. In this review, we summarize the major cells that are closely associated with platelets and discuss the essential role of the interaction between platelets with these cells in tumorigenesis and tumor development.

Role of lymphocyte-related immune-inflammatory biomarkers in detecting early progression of Guillain-Barré syndrome

OBJECTIVES

This study aimed to investigate the role of peripheral neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR), and platelet to lymphocyte ratio (PLR) in the progression and severity of the Guillain-Barré syndrome (GBS).

METHODS

47 GBS patients and 50 age and sex-matched healthy controls (HC) were retrospectively included. Demographic and clinical assessment data were reviewed and abstracted. NLR, MLR, and PLR were calculated based on the peripheral blood tests by reviewing clinical data. The relationship between the Hughes' score and NLR, MLR, PLR levels was investigated.

RESULTS

The GBS patients had higher NLR levels (P < 0.001), MLR levels (P = 0.001) and PLR levels (P < 0.001) than those in HC. And patients with severe disability score (Hughes' score ≥ 3) had significantly higher NLR (P = 0.007), MLR (P = 0.04), PLR (P = 0.013). Spearman correlation analysis indicated that NLR was positively associated with the Hughes' score (r = 0.331, P = 0.023). In the patients with acute inflammatory demyelinating polyneuropathy (AIDP), Spearman correlation analysis indicated that NLR, MLR and PLR were positively associated to the Hughes' score (r = 0.825, P = 0.001 for NLR, r = 0.727, P = 0.005 for MLR, and r = 0.723, P = 0.005 for PLR).

CONCLUSIONS

NLR, MLR, and PLR may be indicators of disease activity in patients with GBS or AIDP. These parameters may benefit the active treatment of GBS patients with a high degree of disability.

A mean platelet volume in inflammatory bowel disease: A systematic review and meta-analysis

Background

Inflammatory bowel disease (IBD) is a chronic gastrointestinal tract inflammatory state, which is affecting millions of individuals in the world. It can affect alimentary canals such as colon, rectum, ileum and other parts. In IBD, platelet parameters underwent several changes. Therefore, the aim of this review was determining the estimated pooled mean platelet volume and mean difference in inflammatory bowel disease to elucidate its potential diagnostic value.

Methods

Articles were extensively searched in bibliographic databases using Medical Subject Heading and entry phrases or terms. In addition, articles were directly searched in Google Scholar to account for the studies omission in searching bibliographic databases. Observational (cohort, cross-sectional and case-control) studies, published in English language and conducted on IBD were included. For studies meeting the eligibility criteria, the first author’s name, publication year, population, study design, study area, sample size, mean platelet volume and standard deviation were extracted and entered in to Microsoft-excel. The analysis was done by Stata version 11. In order to estimate the pooled mean platelet volume and mean difference, random effect model was done. The heterogeneity was quantified using Higgin’s I² statistics. Publication bias was determined using Egger’s test statistics and funnel plot. Sub-group analysis based on population carried to reduce heterogeneity.

Results

A total of 17 relevant articles with 2957 participants (1823 IBD cases and 1134 healthy controls) were included to this study. The pooled estimated MPV was 9.29fl; 95% CI: 9.01–9.57 and 9.50fl; 95% CI: 8.81–10.20 in IBD and control groups, respectively. The standardized pooled estimate of mean difference in mean platelet volume was -0.83fl; 95% CI: -1.15, -0.51; I²: 93.1%; P-value < 0.001. In subgroup analysis based on population, the highest estimated mean difference in MPV was observed among patients of CD; -2.30; 95% CI: -3.46, -1.14; I²: 97.8%; P-value < 0.001.

Conclusion

According to the current systematic review and meta-analysis, mean platelet volume was lower in IBD compared to control. The decreased mean platelet volume could be attributed to platelet consumption or sequestration associated with the progression of IBD. As a result, in IBD, mean platelet volume can provide diagnostic and prognostic information.

Nanodiamond-Induced Thrombocytopenia in Mice Involve P-Selectin-Dependent Nlrp3 Inflammasome-Mediated Platelet Aggregation, Pyroptosis and Apoptosis

Nanodiamond (ND) has been developed as a carrier to conduct various in vivo diagnostic and therapeutic uses. Safety is one of the major considerations, while the hemocompatibility of ND is not clearly addressed. Here we found that, compared to the other sizes of ND with relatively inert properties, treatments of 50 nm ND induced stronger platelet aggregation, platelet pyroptosis, apoptosis and thrombocytopenia in mice. Blockage treatments of soluble P-selectin, reactive oxygen species (ROS), and Nlrp3 inflammasome inhibitors markedly suppressed such adverse effects, suggesting ND-induced platelet activation and pyroptosis involves surface P-selectin-mediated enhancement of mitochondrial superoxide levels and Nlrp3 inflammasome activation. In addition, challenges of NDs induced less platelet pyroptosis and displayed less thrombocytopenia in P-selectin (Selp^-/-), Nlrp3 (Nlrp3^-/-) and caspase-1 (Casp1^-/-) mutants, as compared to the wild type mice. Blockers of P-selectin, ROS, and Nlrp3 inflammasome pathways could be considered as antidotes for ND induced platelet activation and thrombocytopenia.

Endothelial transmigration of platelets depends on soluble factors released by activated endothelial cells and monocytes

Cardiovascular diseases (CVDs) remain leading causes of death worldwide. While platelet-mediated thrombus formation following the rupture of an atherosclerotic plaque is one of the key pathophysiologic events in CVDs, the role of platelets in previous or more advanced stages of atherosclerosis is less known. Interestingly, the presence of platelets has been observed at the core of the atherosclerotic plaque.In order to study the conditions necessary for platelets to migrate toward an atherosclerotic lesion, we designed an in vitro co-culture model. Platelets were co-cultured with monocytes in Transwell inserts covered with a confluent endothelium and the number of migrating platelets and/or monocytes was determined under different conditions. Platelets were also exposed to media conditioned obtained from co-cultures prior to migration assays.Here we show that coculturing platelets and monocytes increased platelet transmigration, with a considerable number of transmigrated platelets found not associated to monocytes. Interestingly, conditioned media from platelet-monocyte co-cultures also increased platelet transmigration and aggregation, suggesting the existence of soluble factors secreted by monocytes that enhance the migratory and pro-aggregating capabilities of platelets.We conclude that platelets have the machinery to migrate through an activated endothelium, a response that requires the interaction with secreted factors produce in the context of the interaction with monocytes under atherogenic conditions.

[Reference ranges of platelet and related parameters within 24 hours after birth in preterm infants with different gestational ages]

OBJECTIVE

To study the reference ranges of platelet and related parameters within 24 hours after birth in preterm infants with different gestational ages.

METHODS

According to the inclusion and exclusion criteria, a retrospective analysis was performed for the chart review data of 1 070 preterm infants with a gestational age of 23-36⁺⁶ weeks who were admitted to the neonatal intensive care unit from January to December in 2018. The reference ranges of platelet parameters were calculated for the preterm infants within 24 hours after birth.

RESULTS

There were no significant differences in platelet count (PLT) and plateletcrit (PCT) among the preterm infants with different gestational ages (P>0.05). The late preterm infants (34-36⁺⁶ weeks; n=667) had significantly lower mean platelet volume (MPV) and platelet distribution width (PDW) than the extremely preterm infants (23-27⁺⁶ weeks; n=36) and the early preterm infants (28-33⁺⁶ weeks; n=367) (P<0.05). There were no significant differences in these platelet parameters between the preterm infants with different sexes (P>0.05). The reference ranges of platelet parameters in preterm infants were calculated based on gestational age. The reference ranges of PLT and PCT were (92-376)×10⁹/L and 0.1%-0.394% respectively, for the preterm infants with a gestational age of 23-36⁺⁶ weeks. The reference ranges of MPV and PDW were 9.208-12.172 fl and 8.390%-16.407% respectively, for the preterm infants with a gestational age of 23-36⁺⁶ weeks; the reference ranges of MPV and PDW were 9.19-11.95 fl and 9.046%-15.116% respectively, for the preterm infants with a gestational age of 34-36⁺⁶ weeks.

CONCLUSIONS

The MPV and PDW of preterm infants with different gestational age are different within 24 hours after birth, and it is more helpful for clinical practice to formulate the reference range of MPV and PDW according to gestational age.

Platelet Function and Therapeutic Applications in Dogs: Current Status and Future Prospects

Significant progress has been made in the functional characterization of canine platelets in the last two decades. The role of canine platelets in hemostasis includes their adhesion to the subendothelium, activation, and aggregation, leading to primary clot formation at the site of injury. Studies on canine platelet function and advancements in laboratory testing have improved the diagnosis and understanding of platelet-related disorders as well as the knowledge of the mechanisms behind these diseases. This review focuses on the most recent discoveries in canine platelet structure, function, and disorders; and discusses the efficacy of various tests in the diagnosis of platelet-related disorders. With the relatively recent discovery of angiogenetic and reparative effects of growth factors found in platelets, this review also summarizes the use of canine platelet-rich plasma (PRP) alone or in association with stem cells in regenerative therapy. The characterization of proteomic and lipidomic profiles and development of platelet gene therapy in veterinary species are areas of future study with potential for major therapeutic benefits.

Platelets can reflect the severity of Crohn's disease without the effect of anemia

OBJECTIVES

Anemia and changes in platelets (PLT) are common in inflammatory bowel disease (IBD). In our study, we aimed to verify whether PLT count can independently reflect the severity of IBD.

METHODS

In our hospital, 137 Crohn's Disease (CD), 69 Ulcerative colitis (UC) patients, and 412 healthy controls were included to compare the differences in PLT count. In addition, the effect of anemia, C-reactive protein (CRP), age, CD activity index (CDAI) or Mayo on PLTs was also analyzed. If PLTs independently affected CD or UC, we used the receiver operating characteristic (ROC) curve to verify the diagnostic value and obtain the cut-off value of PLT.

RESULTS

CD and UC patients had higher PLT than controls (p<0.001, p<0.001; respectively). In CD patients, the results showed that patients with anemia (P<0.01), Iron Deficiency Anemia (IDA) (p<0.001), CRP≥8 mg/L (p=0.046), and CDAI≥150 (p<0.001) had higher PLT, while in UC patients, those with anemia (p=0.018), CRP≥8 mg/L (p=0.045), and Mayo≥3 (p=0.029) had higher PLT. Univariate analysis showed that CDAI was positively correlated with PLT count (p<0.001), while hemoglobin (p=0.001) and age (p<0.001) were negatively correlated with PLT in CD. In UC patients, Mayo (p=0.001) and CRP (p<0.001) were positively correlated with PLT, while hemoglobin (p=0.002) was negatively correlated. Finally, by linear stepwise multivariate analysis, we clarified the positive relationship between PLT and CD (p<0.001) by eliminating the interference of hemoglobin, and determined the cut-off value of PLT as 298×109/L. For UC, we did not obtain similar results.

CONCLUSIONS

PLT can be an indicator of disease severity in CD, while there is a lack of evidence regarding this finding in UC.

Evaluation of the in vitro effects of commercial herbal preparations significant in African traditional medicine on platelets

BACKGROUND

Commercial herbal medicines (CHMs) marketed as immune boosters are gaining wide popularity in South Africa, in the absence of control and regulatory guidelines. These commercially packaged and labelled herbal preparations, acquired in various retail outlets, are used without consulting either a conventional health provider or a traditional health practitioner. Although they are indicated for immune-boosting purposes, they might exert many other beneficial and unwanted effects on physiological systems. Platelets are crucial in haemostasis and important for the immunological system. The aim was to investigate the effect of the CHMs used to strengthen the immune system on the activity of human platelets.

METHODS

Six CHMs commonly used as African traditional medicines in Pretoria, South Africa, were tested for their effects on healthy, isolated human platelets, using a bioluminescence method. The tested herbal medicines were Intlamba Zifo™, Maphilisa™ Herbal medicine, Matla™ African medicine for all diseases, Ngoma™ Herbal Tonic Immune Booster, Stametta™ Body Healing Liquid, and Vuka Uphile™ Immune Booster and serial-diluted standards of each from 10 to 10,000 times. The luminol-enhanced luminescence activity of the platelets was measured after incubation with the herbal medicines and activation with phorbol myristate acetate (PMA) or N-formyl-methionyl-leucyl-phenylalanine (fMLP).

RESULTS

Five herbal medicines, namely Intlamba Zifo™, Maphilisa™ Herbal medicine, Matla™ African medicine for all diseases, Stametta™ Body Healing Liquid, and Vuka Uphile™ Immune Booster exerted comparable weak inhibitory effects on both PMA and fMLP-induced platelets, which were concentration dependent at high doses, and inversely related to concentration at low doses. Intlamba Zifo™, Matla™ African medicine for all diseases, Stametta™ Body Healing Liquid, and Vuka Uphile™ exhibited weak, but non-systematic stimulatory effects at low doses, which were not statistically significant. Ngoma™ Herbal Tonic Immune Booster had weak, inhibitory effects at high doses and weak stimulatory effects that were inversely related to concentration at low doses.

CONCLUSION

The findings suggest a potential beneficial role of the CHMs in the suppression of platelets' reactivity and in enhancing the immune system. Caution, however, should be exercised as platelet inhibition and stimulation predispose to the risk of bleeding and thrombosis, respectively.

Metabolic signature associated with parameters of the complete blood count in apparently healthy individuals

Metabolomics studies now approach large sample sizes and the health characterization of the study population often include complete blood count (CBC) results. Upon careful interpretation the CBC aids diagnosis and provides insight into the health status of the patient within a clinical setting. Uncovering metabolic signatures associated with parameters of the CBC in apparently healthy individuals may facilitate interpretation of metabolomics studies in general and related to diseases. For this purpose 879 subjects from the population‐based Study of Health in Pomerania (SHIP)‐TREND were included. Using metabolomics data resulting from mass‐spectrometry based measurements in plasma samples associations of specific CBC parameters with metabolites were determined by linear regression models. In total, 118 metabolites significantly associated with at least one of the CBC parameters. Strongest associations were observed with metabolites of heme degradation and energy production/consumption. Inverse association seen with mean corpuscular volume and mean corpuscular haemoglobin comprised metabolites potentially related to kidney function. The presently identified metabolic signatures are likely derived from the general function and formation/elimination of blood cells. The wealth of associated metabolites strongly argues to consider CBC in the interpretation of metabolomics studies, in particular if mutual effects on those parameters by the disease of interest are known.

Is high platelet distribution width in the first hours of life can predict hemodynamically significant patent ductus arteriosus in preterm newborns?

Aim: To determine whether there is any association between platelet indices within the first hours of life and hemodynamically significant patent ductus arteriosus (hsPDA) in preterm newborns.Patient and methods: A total of 100 preterm infants, gestational age <32 weeks and birth weight <1500 g were analyzed in the study. Complete blood counts obtained within the first 6 hours of life were evaluated for platelet parameters and compared for patent ductus arteriosus (PDA) status.Results: We included 50 infants with hsPDA and 50 controls. Mean gestational week of patients were 28.8 ± 2.4 weeks and mean birth weight of the patients were 1237.5 ± 406 g. Platelet distribution width (PDW) is higher in PDA group compared with the control group (p = .023). The cutoff value of PDW is 11.45 fL for hsPDA with 65% sensitivity and 66% specificity. The other blood parameters including platelet count, platelet mass, and mean platelet volume (MPV) were no statistically different between the two groups. Also, there was no association with the platelet count and the response to the medical therapy.Conclusions: There is no association between hsPDA and the platelet count, platelet mass or MPV in the first day of life. We determined that hsPDA patency was significantly associated with a higher first day PDW level, which is a more specific indicator of platelet activation than other platelet parameters.

Association of Neutrophil/Lymphocyte Ratio With Intravenous Immunoglobulin Treatment in Children With Guillain-Barré Syndrome

Guillain-Barré syndrome (GBS) is an acute immune-mediated inflammatory polyneuropathy of the peripheral nervous system. The authors aimed to investigate whether the neutrophil/lymphocyte (N/L) and platelet/lymphocyte (P/L) ratios are the parameters that associated with the drug treatment or severity of GBS. Twenty-seven children with GBS were retrospectively analyzed from the medical records of patients who attended to the Pediatric Neurology Department of the Gaziantep University Hospital. Biochemical and hematologic parameters were measured. Leukocytes, neutrophils counts and N/L ratio were significantly higher before the intravenous immunoglobulin treatment ( P < .001). However, there were no marked differences in platelet count and P/L ratio. In addition, marked correlation was observed between the N/L ratio after treatment and duration of weakness. The results of the study showed that N/L ratio is significantly higher in GBS patients, and reduces following with intravenous immunoglobulin treatment.

Is there a relationship between platelet parameters and patency of ductus arteriosus in preterm infants?

Postnatal closure of the ductus arteriosus is a complicated two-phase process involving functional and structural changes. So far, the precise mechanisms regulating this process are not fully understood. A growing body of evidence from recent studies suggests that platelets play a key role in inflammatory processes including ductal closure via interaction with endothelial cells. The aim of this study is to assess whether a relationship exists between the occurrence and/or closure of hemodynamically significant ductus arteriosus (HSDA) and platelet parameters (platelet count, circulating platelet mass, mean platelet volume, platelet distribution width) in preterm newborns. This single-center, retrospective study included 824 premature infants between 24 and 34 gestational weeks, evaluated by echocardiography at postnatal 72-96 h. Infants with and without HSDA (n = 208 vs. n = 616) were compared in terms of platelet parameters recorded within the first 3 days of life. Oral or intravenous ibuprofen was commenced for medical treatment, and echocardiography was repeated 24 h thereafter to determine ductal closure. No statistically significant difference could be demonstrated between the groups in terms of baseline platelet parameters. HSDA was independently associated with early-onset neonatal sepsis. Thrombocytopenia, low circulating platelet mass, high platelet distribution width, or high mean platelet volume could not be demonstrated as a risk factor for HSDA. None of the platelet parameters had an influence on ductal closure after medical treatment. Unlike most reports in the literature, presence of HSDA was not associated with any platelet parameter in our study. We could not demonstrate an association between any platelet parameter and either persistence or closure after medical treatment.

Changes in platelet parameters in leukocytosis

Introduction

In recent years, platelets are known to have a large variety of functions in many pathophysiological processes and their interaction with endothelial cells and leukocytes is known to play an important role in the pathophysiology of vascular inflammation. The aim of this study was to investigate the relationship between white blood cell count in conditions resulting in leukocytosis and platelet count and platelet parameters including mean platelet volume, platelet distribution width, and plateletcrit.

Methods

White blood cell counts count and all platelet parameters were evaluated in 341 results of normal complete blood count (of which the white blood cell counts were within reference range, group 1) and 327 results of elevated white blood cell counts count (group 2).

Results

There was a significant difference between these two groups in PLT counts and PCT values, being higher in Group 2. However, there was no statistically significant difference between two groups in MPV and PDW values. On the other hand, there were statistically significant, but weak, correlations between the WBC and platelet counts in both groups (p<0.01, r=0.235 for group 1, p<0.05, r=0.116 for group 2).

Conclusion

As a conclusion PLT count and PCT values increase in infectious conditions. This study and previous studies show that PLTs are employed in infectious conditions but the exact mechanism and the exact clinical importance of this response remains to be cleared by further studies.

Platelets at the interface of thrombosis, inflammation, and cancer

Although once primarily recognized for its roles in hemostasis and thrombosis, the platelet has been increasingly recognized as a multipurpose cell. Indeed, circulating platelets have the ability to influence a wide range of seemingly unrelated pathophysiologic events. Here, we highlight some of the notable observations that link platelets to inflammation, reinforcing the platelet's origin from a lower vertebrate cell type with both hemostatic and immunologic roles. In addition, we consider the relevance of platelets in cancer biology by focusing on the hallmarks of cancer and the ways platelets can influence multistep development of tumors. Beyond its traditional role in hemostasis and thrombosis, the platelet's involvement in the interplay between hemostasis, thrombosis, inflammation, and cancer is likely complex, yet extremely important in each disease process. The existence of animal models of platelet dysfunction and currently used antiplatelet therapies provide a framework for understanding mechanistic insights into a wide range of pathophysiologic events. Thus, the basic scientist studying platelet function can think beyond the traditional hemostasis and thrombosis paradigms, while the practicing hematologist must appreciate platelet relevance in a wide range of disease processes.

Multipotent role of platelets in inflammatory bowel diseases: A clinical approach

There is evidence that inflammatory bowel diseases (IBD) combine both inflammation and coagulation in their pathogenesis and clinical manifestations. Although platelets (PLT) are well known for their role in hemostasis, there are a rising number of studies supporting their considerable role as inflammatory amplifiers in chronic inflammatory conditions. IBD are associated with several alterations of PLT, including number, shape, and function, and these abnormalities are mainly attributed to the highly activated state of circulating PLT in IBD patients. When PLT activate, they increase in size, release a great variety of bio-active inflammatory and procoagulant molecules/particles, and express a variety of inflammatory receptors. These inflammatory products may represent a part of the missing link between coagulation and inflammation, and can be considered as possible IBD pathogenesis instigators. In clinical practice, thrombocytosis is associated both with disease activity and iron deficiency anemia. Controlling inflammation and iron replacement in anemic patients usually leads to a normalization of PLT count. The aim of this review is to update the role of PLT in IBD and present recent data revealing the possible therapeutic implications of anti-PLT agents in future IBD remedies.

Bioprosthetic heart valves of the future

Glutaraldehyde-fixed bioprosthetic heart valves (GBHVs), derived from pigs or cows, undergo structural valve deterioration (SVD) over time, with calcification and eventual failure. It is generally accepted that SVD is due to chemical processes between glutaraldehyde and free calcium ions in the blood. Valve companies have made significant progress in decreasing SVD from calcification through various valve chemical treatments. However, there are still groups of patients (e.g., children and young adults) that have accelerated SVD of GBHV. Unfortunately, these patients are not ideal patients for valve replacement with mechanical heart valve prostheses as they are at high long-term risk from complications of the mandatory anticoagulation that is required. Thus, there is no "ideal" heart valve replacement for children and young adults. GBHVs represent a form of xenotransplantation, and there is increasing evidence that SVD seen in these valves is at least in part associated with xenograft rejection. We review the evidence that suggests that xenograft rejection of GBHVs is occurring, and that calcification of the valve may be related to this rejection. Furthermore, we review recent research into the transplantation of live porcine organs in non-human primates that may be applicable to GBHVs and consider the potential use of genetically modified pigs as sources of bioprosthetic heart valves.

Platelet function beyond hemostasis and thrombosis

PURPOSE OF REVIEW

The platelet paradigm that is well established in hemostasis and thrombosis can be extended to other disease states. A consideration for some major health issues, such as inflammation, cancer, infection, and neuroscience, and how platelet function impacts the pathophysiology of each clinical situation is provided.

RECENT FINDINGS

Decades of research and knowledge of platelet function exist and the same is true for inflammation and cancer. The literature is full of platelet biology overlapping into other, nonthrombotic disease states. However, major gaps exist that prevent a complete mechanistic understanding of platelet function in these other diseases. Although much of the overlap provides antidotal relationships, future studies will likely uncover novel pathophysiological pathways that are highly relevant to human diseases.

SUMMARY

Recent findings in four major disease areas, inflammation, cancer, infection, and neuroscience, are described, with current literature linking the disease to platelet function. The availability of antiplatelet therapies, such as aspirin, exists and future consideration can be given as to whether antiplatelet therapy is potentially beneficial or harmful as the mechanisms of platelet involvement are better defined.