富血小板血浆对骨髓间充质干细胞成骨向分化的作用

目的:观察不同浓度改良富血小板血浆(PRP)对骨髓间充质干细胞(BMSCs)成骨向分化的作用效果。方法:使用健康志愿者骨髓培养的3~4代BMSCs。将由该志愿者静脉采集的静脉血制备成改良PRP作用于BMSCs,使用碱性磷酸酶(ALP)试剂盒测定矿化诱导7 d后BMSCs的ALP活性,通过茜素红染色观察矿化诱导21 d后BMSCs的矿化结节形成情况,并通过实时荧光定量PCR检测矿化诱导7 d后BMSCs中成骨相关基因Runx2表达的变化。结果:5%改良PRP明显提高了BMSCs的ALP活性,促进了其矿化结节的形成,并上调了BMSCs中Runx2基因的表达。结论:液氮冻融激活的改良PRP促进BMSCs成骨向分化具有浓度特异性。     

Thrombocyte serotonin and serum cholesterol concentration in suicidal and non-suicidal depressed patients

Introduction

Numerous studies have confirmed the connection of reduced serum cholesterol and thrombocyte serotonin concentration with suicidal behavior in psychiatric patients. The purpose of such studies was to determine the link among cholesterol and serotonin concentration, comparing depressed patients with and without attempted suicide with phenotypically healthy control group.

Materials and methods

The examinees' groups consisted of 55 depressed patients with suicide attempt and 77 depressed patients with no suicide attempt. In accordance to ICD-10, the above patients were separated in two subgroups; F32.2 and F33.2. Phenotypically healthy control group was presented by the group of healthy blood donors. The fasting serum cholesterol concentration was established using standard enzymatic method, while the thrombocyte serotonin concentration was determined by the enzymatic immune-chemical method (ELISA).

Results

The ANOVA test (N = 228, F_ratio = 8.26, p < 0.001) found significant difference of cholesterol concentration between groups, with lowest concentration in depressed patients with attempted suicide (SNK post hoc test, p < 0.05). Upon gender stratification, the significance remained for the female patients (ANOVA, N = 125, F_ratio = 6.06, p = 0.003). The serum cholesterol was shown to be statistically lower in the group of depressed patients with attempted suicide, diagnoses F32.2 (p = 0.031) and F33.2 (p = 0.011), compared to the group of depressed patients without attempted suicides. The thrombocyte serotonin was found to be significantly different in all examined groups, with the lowest thrombocyte serotonin in the group of depressed patients with no suicide attempt (SNK post hoc test, p < 0.05, N = 187, F_ratio = 37.69, p < 0.001). The same significance was found for the group of female (ANOVA, N = 103, F_ratio = 11.81, p < 0.001) and the group of male patients (ANOVA, N = 84, F_ratio = 30.40, p < 0.001). The thrombocyte serotonin was significantly lower in the group of depressed patients with no suicide attempt (F32.2), compared to the same diagnosis in the group of depressed patients with suicide attempt (MW-test, p = 0.018).

Conclusion

In the group of depressed patients with attempted suicide, statistically significant lower serum cholesterol values have been confirmed. In the group of depressed patients with no suicide attempt, statistically significant lower values of thrombocyte serotonin have been confirmed, presumably as the response to the psychopharmacological therapy.     

Effects of platelet‐rich plasma on the quality of repair of mechanically induced core lesions in equine superficial digital flexor tendons: A placebo‐controlled experimental study

Tendon injuries are notorious for their slow and functionally inferior healing. Intratendinous application of platelet‐rich plasma (PRP) has been reported to stimulate the repair process of tendon injuries, but there is little conclusive evidence for its effectiveness. A placebo‐controlled experimental trial was performed to test the hypothesis that a single intratendinous PRP treatment enhances the quality of tendon repair, as evidenced by improved biochemical, biomechanical, and histological tissue properties. In six horses, tendon lesions were created surgically in the Superficial Digital Flexor Tendons (SDFT) of both front limbs, one of which was treated with PRP and the other with saline. After 24 weeks, the tendons were harvested for biochemical, biomechanical, and histological evaluations. Collagen, glycosaminoglycan, and DNA content (cellularity) was higher in PRP‐treated tendons (p = 0.039, 0.038, and 0.034, respectively). The repair tissue in the PRP group showed a higher strength at failure (p = 0.021) and Elastic Modulus (p = 0.019). Histologically, PRP‐treated tendons featured better organization of the collagen network (p = 0.031) and signs of increased metabolic activity (p = 0.031). It was concluded that PRP increases metabolic activity and seems to advance maturation of repair tissue over nontreated experimentally induced tendon lesions, which suggests that PRP might be beneficial in the treatment of clinical tendon injuries. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:211–217, 2010     

Mice with deleted multimerin 1 and α-synuclein genes have impaired platelet adhesion and impaired thrombus formation that is corrected by multimerin 1

Background

Multimerin 1 is a stored platelet and endothelial cell adhesive protein that shows significant conservation. In vitro, multimerin 1 supports platelet adhesion and it also binds to collagen and enhances von Willebrand factor-dependent platelet adhesion to collagen. As selective, multimerin 1 deficient mice have not been generated, we investigated multimerin 1 effects on platelet adhesion using a subpopulation of C57BL/6J mice with tandem deletion of the genes for multimerin 1 and α-synuclein, a protein that inhibits α-granule release in vitro. We postulated that multimerin 1/α-synuclein deficient mice might show impaired platelet adhesive function from multimerin 1 deficiency and increased α-granule release from α-synuclein deficiency.

Methods

Platelet function was assessed by intravital microscopy, after ferric chloride injury, using untreated and human multimerin 1-transfused multimerin 1/α-synuclein deficient mice, and by in vitro assays of adhesion, aggregation and thrombin-induced P-selectin release.

Results

Multimerin 1/α-synuclein deficient mice showed impaired platelet adhesion and their defective thrombus formation at sites of vessel injury improved with multimerin 1 transfusion. Although multimerin 1/α-synuclein deficient platelets showed increased P-selectin release at low thrombin concentrations, they also showed impaired adhesion to collagen, and attenuated aggregation with thrombin, that improved with added multimerin 1.

Conclusions

Our data suggest that multimerin 1 supports platelet adhesive functions and thrombus formation, which will be important to verify by generating and testing selective multimerin 1 deficient mice.     

Mechanism of collagen-induced release of 5-HT, PDGF-AB and sCD40L from human platelets: Role of HSP27 phosphorylation via p44/p42 MAPK

Collagen plays a crucial role in hemostasis and thrombosis by activating platelets and reportedly induces the phosphorylation of heat shock protein (HSP) 27 in human platelets. However, the exact role of HSP27 phosphorylation in human platelets has not yet been clarified. In the present study, we investigated the mechanism of collagen-induced HSP27 phosphorylation and the role in human platelets. The collagen-effect on the phospholylation of HSP27 was dose-dependent in the range between 0.03 and 1.0 μg/ml. The phosphorylation of p44/p42 mitogen-activated protein kinase (MAPK) was also stimulated by collagen. PD98059, a specific inhibitor of MAPK kinase (MEK1/2), reduced collagen-induced HSP27 phosphorylation as well as p44/p42 MAPK phosphorylation. PD98059 significantly suppressed collagen-induced releases of serotonin (5-HT), platelet-derived growth factor (PDGF)-AB and soluble CD40 ligand (sCD40L) while it had little effect on the platelet aggregation. These results strongly suggest that the collagen-induced phosphorylation of HSP27 via p44/p42 MAPK is sufficient for releases of 5-HT, PDGF-AB and sCD40L from human platelets.     

PGE2 decreases reactivity of human platelets by activating EP2 and EP4

Introduction

Platelet hyperreactivity associates with cardiovascular events in humans. Studies in mice and humans suggest that prostaglandin E₂ (PGE₂) regulates platelet activation. In mice, activation of the PGE₂ receptor subtype 3 (EP3) promotes thrombosis, but the significance of EP3 in humans is less well understood.

Objectives

To characterize the regulation of thromboxane-dependent human platelet activation by PGE₂.

Patients/Methods

Platelets collected from nineteen healthy adults were studied using an agonist of the thromboxane receptor (U46,619), PGE₂, and selective agonists and/or antagonists of the EP receptor subtypes. Platelet activation was assayed by (1) optical aggregometry, (2) measurement of dense granule release, and (3) single-platelet counting.

Results

Healthy volunteers demonstrated significant interindividual variation in platelet response to PGE₂. PGE₂ completely inhibited U46,619-induced platelet aggregation and ATP release in 26% of subjects; the remaining 74% had partial or no response to PGE₂. Antagonism of EP4 abolished the inhibitory effect of PGE₂. In all volunteers, a selective EP2 agonist inhibited U46,619-induced aggregation. Furthermore, the selective EP3 antagonist DG-041 converted all PGE₂ nonresponders to full responders.

Conclusions

There is significant interindividual variation of platelet response to PGE₂ in humans. The balance between EP2, EP3, and EP4 activation determines its net effect. PGE₂ can prevent thromboxane-induced platelet aggregation in an EP4-dependent manner. EP3 antagonism converts platelets of nonresponders to a PGE₂-responsive phenotype. These data suggest that therapeutic targeting of EP pathways may have cardiovascular benefit by decreasing platelet reactivity.     

Distinct patterns of neuronal inputs and outputs of the juxtaparaventricular and suprafornical regions of the lateral hypothalamic area in the male rat

We have analyzed at high resolution the neuroanatomical connections of the juxtaparaventricular region of the lateral hypothalamic area (LHAjp); as a control and in comparison to this, we also performed a preliminary analysis of a nearby LHA region that is dorsal to the fornix, namely the LHA suprafornical region (LHAs). The connections of these LHA regions were revealed with a coinjection tract-tracing technique involving a retrograde (cholera toxin B subunit) and anterograde (Phaseolus vulgaris leucoagglutinin) tracer. The LHAjp and LHAs together connect with almost every major division of the cerebrum and cerebrospinal trunk, but their connection profiles are markedly different and distinct. In simple terms, the connections of the LHAjp indicate a possible primary role in the modulation of defensive behavior; for the LHAs, a role in the modulation of ingestive behavior is suggested. However, the relation of the LHAjp and LHAs to potential modulation of these behaviors, as indicated by their neuroanatomical connections, appears to be highly integrative as it includes each of the major functional divisions of the nervous system that together determine behavior, i.e., cognitive, state, sensory, and motor. Furthermore, although a primary role is indicated for each region with respect to a particular mode of behavior, intermode modulation of behavior is also indicated. In summary, the extrinsic connections of the LHAjp and LHAs (so far as we have described them) suggest that these regions have a profoundly integrative role in which they may participate in the orchestrated modulation of elaborate behavioral repertoires.     

Serologic testing to verify the immune status of internationally adopted children against vaccine preventable diseases

Definitive immunization guidelines for internationally adopted children are lacking. We examined whether these children had serologic evidence of protection against vaccine-preventable diseases. For children with ≥3 vaccine doses, overall protection was high for diphtheria (85%), tetanus (95%), polio (93%), hepatitis B (77%), and Hib (67%). For children ≥12 months of age with ≥1 dose of measles, mumps, or rubella vaccines, 95%, 72%, and 94% were immune, respectively. Children without immunization documentation had lower immunity. Serologic testing was useful in verifying the immunization status in internationally adopted children with and without documentation of immunizations.     

Clinical efficacy of platelet rich plasma in combination with methotrexate in chronic plaque psoriatic patients

Psoriasis affects up to 3% of the world's population or more than 125 million people. There is an urgent need for new treatment strategy, as up to 50% of patients are not satisfied with current therapies. We evaluated the combined efficiency of platelet rich plasma (PRP) and methotrexate (MTX) in the management of patients with plaque psoriasis. Twenty‐one patients with chronic plaque psoriasis were recruited in the study. Sixteen patients were assigned into combinational treatment group (PRP + MTX) and monotherapy group (MTX alone) consisted of five patients. All patients in combinational therapy received autologous PRP in their first sitting and subsequently followed with folitrax‐15 for 4 weeks, while patients in monotherapy group received only folitrax‐15, all patients received intra‐lesional injections. Digital photograph, Psoriasis Area Severity Index (PASI) score and adverse events were recorded at weeks 0, 4, 8, 12 and 16 and were evaluated by three investigators independently. Patients treated with PRP/MTX showed substantial improvement in term of reduction in erythema, induration and desquamation at each visit and was effectively cleared off psoriasis at week 16. Combination treatment of PRP with MTX was well tolerated by all patients without any serious adverse events.     

富血小板血浆联合骨髓间充质干细胞不同 配比浓度对兔软骨缺损的影响

目的: 研究富血小板血浆(PRP)与骨髓间充质干细胞(BMSCs)不同的配比浓度对兔软骨缺损的治疗效果。方法: 随机将60只新西兰兔随机分为模型对照组、PRP组(3%)、BMSCs组(1×10⁶/mL)、不同配比浓度的PRP+BMSCs联合组(1:5,2:5,3:5)。建立兔软骨损伤模型,术后第2周靶侧肌肉注射不同配比浓度的PRP与BMSCs,每周1次,连续给药4周。采用Masson's三色染色法,观察关节软骨缺损情况;采用Pineada法进行关节软骨组织学半定量计分,并通过观察患兔术膝切口,了解术后愈合情况。结果: 与模型对照组比较,不同配比浓度的PRP与BMSCs联合组中的关节软骨半定量分值均减少(P<0.05)。不同配比浓度的PRP与BMSCs联合组中,关节软骨半定量分值随PRP浓度的增加而减少,关节软骨半定量分值与PRP值呈现线性关系,其中PRP与BMSCs配比浓度为3:5的效果最为明显,差异有显著性意义(P<0.05)。结论: PRP,BMSCs在一定程度上可促进骨组织恢复;关节软骨缺损恢复程度与PRP浓度表现出一定的量效关系。