Arrest Of Bleeding Research Articles

A Hybrid Approach to Direct Pulp Capping by Using Emdogain with a Capping Material

Introduction This study evaluated the formation of reparative hard tissues in baboon pulps after Emdogain (EMD) application in conjunction with 3 pulp-capping materials. Methods Thirty-two premolars in four 3-year-old baboons were randomly assigned to 1 of 3 pulp-capping materials. A split-mouth design and intra-animal side randomization were applied to 3 ex-perimental groups (calcium hydroxide, ProRoot White mineral trioxide aggregate, white Portland cement) and the control group (no pulp-capping material). In the hybrid EMD approach, a small drop of EMD was placed over the exposure site after arrest of hemorrhage. The designated pulp-capping material was placed over the EMD, followed by placement of resin-modified glass ionomer cement over the set/unset pulp-capping material. The animals were killed after 4 months. Histomorphometric analysis and micro–computed tomography were performed on the re-trieved specimens. Results All groups capped with EMD and 1 of the 3 capping materials exhibited similar reparative tissue thickness ( P > .05). Dentin tunnel defects were absent in the mineral trioxide aggregate and Portland cement groups after the use of EMD. However, only a tubular was identified from all specimens. Conclusions Mineral trioxide aggregate produces a better quality reparative hard tissue response with the adjunctive use of Emdogain, when compared with the use of calcium hydroxide.

Experience with a single dose of recombinant activated factor VII for the management of mild-to-moderate bleeds in haemophilia

Experience with a single dose of recombinant activated factor VII for the management of mild-to-moderate bleeds in haemophilia

Role of recombinant factor VIIa in the treatment of intractable bleeding in vascular surgery

Most recent publications have shown that the recombinant form of activated factor VII (rFVIIa; NovoSeven, Novo Nordisk A/S, Bagsværd, Denmark) induces excellent hemostasis in patients with severe intractable bleeding caused by trauma and major surgery. The purpose of this study was to determine the influence of rFVIIa on the treatment of intractable perioperative bleeding in vascular surgery when conventional hemostatic measures are inadequate. There were two groups of patients: the NovoSeven group (group N), 10 patients with ruptured abdominal aortic aneurysms (RAAAs) and 14 patients operated on due to thoracoabdominal aortic aneurysms (TAAAs); the control group (group C), 14 patients with RAAAs and 17 patients with TAAAs. All patients suffered intractable hemorrhage refractory to conventional hemostatic measures, while patients from group N were additionally treated with rFVIIa. Postoperative blood loss was significantly lower in group N treated with rFVII (P < .0001). Postoperative administration of packed red blood cells, fresh frozen plasma, and platelets was lower in patients from group N, (P < .0001). Successful hemorrhage arrest was reported in 21 patients (87.5%) treated with rFVIIa, and in 9 patients (29.03%) in group C (P < .001). Thirty-day mortality in these two groups significantly differed. The mortality rate was 12.5% (3 patients) in group N and 80.65% (25 patients) in group C (P < .0001). Our findings suggest that rFVIIa may play a role in controlling the intractable perioperative and postoperative bleeding in surgical patients undergoing a repair of RAAAs and TAAAs. Certainly, prospective randomized trials are necessary to further confirm the efficacy and cost-effectiveness of rFVIIa in these patients.

Co-Trafficking of Coagulation Factor VIII with Von Willebrand Factor Alters the Macromolecular Structure Inside Secretory Weibel-Palade Bodies

AbstractAbstract 325The liver is generally recognized as the major site of coagulation factor (F)VIII synthesis. However, there is now increasing evidence that FVIII can also be synthesized in specific endothelial cells where it is stored with its natural carrier protein von Willebrand factor (VWF) in the Weibel-Palade bodies (WPBs). WPBs have a typical cigar-shaped appearance that most likely originates from the macromolecular organization of VWF multimers into tubules. The tubular storage of VWF is thought to be essential for orderly secretion of VWF strings during activation of endothelial cells. Recently we have shown that expression of FVIII with VWF changes the WPB morphology to spherical vesicles. This finding suggests alterations in the biochemical properties of stored VWF. We now studied in detail the effect of FVIII co-expression on the VWF molecule using a combination of innovative techniques, including correlative light-electron microscopy (CLEM), and live-cell fluorescence microscopy under flow conditions. Analysis of human blood outgrowth endothelial cells (BOECs) expressing human B-domain deleted FVIII-GFP by CLEM revealed that FVIII containing WPBs were electron-dense, spherical structures. These structures contained disorganized short VWF tubules, which was confirmed in 3D by electron tomography. Double immunogold labelling with VWF and GFP antibodies showed that the spherical FVIII containing structures were always positive for VWF. These observations imply that FVIII blocks the expansion of VWF tubules, possibly by binding to the N-terminal VWF domains. As the N-terminal domains are also implicated in the formation of multimers, we therefore investigated whether FVIII affects VWF multimer size. Indeed, multimer analysis showed that VWF secreted by FVIII-GFP transduced BOECs was multimerized to a lesser extent when compared to VWF secreted by non-transduced BOECs. The combined absence of high molecular weight (HMW) VWF multimers and long VWF tubules made us question whether these cells could still release ultra-large VWF (UL-VWF) strings. UL-VWF strings play a key role in bleeding arrest, as platelets adhere to the released VWF string which ultimately leads to the formation of a platelet plug. We examined the release of UL-VWF strings under shear stress from BOECs expressing FVIII-GFP employing live-cell confocal imaging. This technique allowed us to follow FVIII release during exocytosis of WPBs in real-time as well. When we stimulated FVIII-transduced BOECs with histamine, these cells were equally able to release VWF strings as non-transduced BOECs. Although spherical WPBs lacked long VWF tubules and did not secrete HMW multimers, released VWF strings were of similar length as strings secreted by non-transduced BOECs. Surprisingly, released VWF strings were completely covered with FVIII which remained attached to the strings throughout the whole experiment. Another remarkable observation was that platelet binding to the FVIII-covered VWF strings was almost completely absent. We hypothesize that FVIII either shields the A1 domain for platelet binding or causes a conformational change in the VWF strings that prevents platelets from binding to the strings. Our results demonstrate that FVIII co-trafficking with VWF has a major impact on properties of VWF as it reduces the degree of multimerization, shortens tubules and prevents platelets from adhering to strings. This leads us to the conclusion that the macromolecular structure of VWF is considerably altered when FVIII is present in WPBs. Disclosures:No relevant conflicts of interest to declare.

Current practice in the management of muscle haematomas in patients with severe haemophilia

Muscle haematomas (MH) represent 10-25% of all bleeds in patients with severe haemophilia. We performed a cross-sectional survey on current practice in the management of MH with participation from 22 consultants. The respondents reported 492 MH/year, corresponding an average of 25/centre, mostly associated with trauma. Iliopsoas (55%), calf (18%) and thigh (18%) bleeds were scored as most serious. Half of the respondents distinguished between contusion and strains, whereas the majority (68.2%) did not categorize bleedings as intra- or intermuscular, although 77.3% routinely used ultrasound. Half of the respondents used a standard protocol for the management of MH. Twenty of 22 (90.9%) respondents offered physiotherapy in the hospital following MH, with no clear consensus on timing and type of treatment. In a theoretical case, for a 70-kg patient with a soleus triceps haematoma, the average initial dose of factor VIII was 2730 U (range: 1750-4000) twice daily for 3-5 days. In a similar case of a patient with inhibitors, 31.8% reported first-line and only use of either recombinant factor VIIa (rFVIIa) or activated prothrombin complex concentrate (APCC), while 36.4% switched between bypassing agents. Using rFVIIa, the median dose was 100 μg/kg (range: 85-270) and with APCC, the median dose was 70 U kg(-1) (range: 50-100). The majority (68.2%) did not use antifibrinolytics. Resolution of pain (81.8% & 77.3%) was regarded as the key clinical marker of arrest of bleeding as compared with diminished swelling and improved range of motion. The survey outlines limited consensus in the management of MH in patients with haemophilia and highlights potential topics for future studies.

Inherited disorders of platelet function and challenges to diagnosis of mucocutaneous bleeding

Platelets play a pivotal role in the arrest of bleeding at sites of vascular injury. Following endothelial damage, they respond rapidly by adhesion to subendothelial matrix proteins resulting in platelet activation, spreading, aggregation, secretion and recruitment of additional platelets to form the primary haemostatic plug. This mass provides a surface for thrombin generation and fibrin mesh formation that stabilizes the clot. Careful study of patients with inherited platelet disorders and, subsequently, of informative animal models, has identified structural platelet abnormalities that have enhanced our understanding of platelet function. The investigations of rare, but severe, inherited platelet disorders have led us to the discovery of causative molecular defects. One of the most informative is the rare autosomal recessive disorder Glanzmann thrombasthenia, caused by defect or deficiency in the platelet integrin alphaIIbbeta3, resulting in absent platelet aggregation and a significant clinical bleeding diathesis. Our new challenge is to understand the mechanisms underlying more common, but less well-defined, mucocutaneous bleeding (MCB) disorders. Present diagnostic testing for platelet function disorders and von Willebrand's Disease often fails to identify the cause of bleeding in individuals with inherited MCB.

Angiodysplasie colique et hémodialyse chronique. Traitement par coagulation au plasma argon. À propos d’un cas

Introduction Gastrointestinal angiodysplasia is a very common cause of digestive haemorrhage among patients with chronic renal insufficiency. It is well known that bleeding from angiodysplasias can be a difficult therapeutic problem since therapeutic possibilities are scarce and surgery is scolded with high mortality rate. Endoscopic argon plasma ablation therapy is a new, effective and safe treatment in the management of gastrointestinal angiodysplasia. Case report We reported a case of a female haemodialysis patient aged 40 years. She was haemodialysed since 6 years in our center from unknown nephropathy. In March 2006, she complained of black stools and melena, and developed severe anaemia (Haemoglobin at 4 g/dL). Exploratory endoscope examination of the digestive tract showed the presence of bleeding from angiodysplastic lesions of the right colon. The patient had severe clinical picture extension of angiodysplastic lesions and frequent bleeding episodes. Bleeding arrest was observed after argon plasma coagulation, with a significant decrease of blood transfusions and improvement of anaemia. Conclusion Gastrointestinal angiodysplasia was reported to be an important complication in dialysis patients and was recognized as an important cause of erythropoietin-resistant anaemia. It can worsen vital prognosis. Argon plasma coagulation is an effective treatment in these patients.

Use of the novel hemostatic textile Stasilon® to arrest refractory retroperitoneal hemorrhage: a case report

IntroductionStasilon® is a novel hemostatic woven textile composed of allergen-free fibers of continuous filament fiberglass and bamboo yarn. The development of this product resulted from controlled in vitro thrombogenic analysis of an array of potentially hemostatic textile materials and it has been cleared for both external and internal use by the United States Food and Drug Administration for the arrest of hemorrhage. The goal of the study was to assess the hemostatic and adhesive properties of Stasilon® in the setting of life-threatening refractory hemorrhage.Case presentationA 39-year-old Caucasian man presented with severe necrotic pancreatitis that failed multiple aggressive attempts to control associated bleeding with electrocautery, suture ligation, and sequential anatomic packing with cotton-based sponges. Subsequent retroperitoneal packing with Stasilon® produced a non-adherent wound-dressing interface and resulted in the achievement of persistent hemostasis in the operative field.ConclusionIn our patient, Stasilon® was demonstrated to be effective in the arrest of refractory hemorrhage.

Loss of matrix metalloproteinase 2 in platelets reduces arterial thrombosis in vivo

Platelet activation at a site of vascular injury is essential for the arrest of bleeding; however, excessive platelet activation at a site of arterial damage can result in the unwarranted formation of arterial thrombi, precipitating acute myocardial infarction, or ischemic stroke. Activation of platelets beyond the purpose of hemostasis may occur when substances facilitating thrombus growth and stability accumulate. Human platelets contain matrix metalloproteinase 2 (MMP-2) and release it upon activation. Active MMP-2 amplifies the platelet aggregation response to several agonists by potentiating phosphatidylinositol 3-kinase activation. Using several in vivo thrombosis models, we show that the inactivation of the MMP-2 gene prevented thrombosis induced by weak, but not strong, stimuli in mice but produced only a moderate prolongation of the bleeding time. Moreover, using cross-transfusion experiments and wild-type/MMP-2−/− chimeric mice, we show that it is platelet-derived MMP-2 that facilitates thrombus formation. Finally, we show that platelets activated by a mild vascular damage induce thrombus formation at a downstream arterial injury site by releasing MMP-2. Thus, platelet-derived MMP-2 plays a crucial role in thrombus formation by amplifying the response of platelets to weak activating stimuli. These findings open new possibilities for the prevention of thrombosis by the development of MMP-2 inhibitors.

Development and validation of the revised injury severity classification score for severely injured patients.

Trauma scores are often used for prognostication and the adjustment of mortality data. The appropriate consideration of identified prognostic factors is mandatory for a valid score with good outcome prediction properties. The Trauma Registry of the German Society for Trauma Surgery (TR-DGU) initially used the Trauma and Injury Severity Score (TRISS) but various reasons led to the development of a new scoring system, the Revised Injury Severity Classification (RISC). A total of 2,008 severely injured patients with complete data documented in the TR-DGU during the period 1993-2000 were used to develop a new score. Patients were split into a development sample (n = 1,206) and a validation sample (n = 802). Multivariate logistic regression analysis was applied, and the results were compared with existing score systems. The quality of prediction was determined regarding discrimination (disparity, sensitivity, specificity, receiver operating characteristic [ROC] curve), precision (predicted versus observed mortality), and calibration (Hosmer-Lemeshow goodness-of-fit). Existing score systems (ISS, NISS, RTS, ASCOT, TRISS, Rixen) revealed areas under the ROC curve ranging from 0.767 to 0.877. The RISC combines 11 different components: age, NISS, head injury, severe pelvic injury, Glasgow Coma Scale, partial thromboplastin time (PTT), base excess, cardiac arrest, and indirect signs of bleeding (shock, mass transfusion, and low hemoglobin). The new RISC score reached significantly higher values of above 0.90 for the area under the ROC curve in both development and validation samples. Application to data from 2001 confirmed these results. Outcome prediction including initial laboratory values was able to significantly improve the ability to discriminate between survivors and nonsurvivors. The adjustment of mortality rates should be based on the best available prediction model.

Lifesaving Embolization of Coronary Artery Perforation

Coronary artery perforation remains one of the most fearsome complications during cardiac catheterization procedures. Although emergent bypass surgery is the preferred treatment for cases with uncontrollable perforation, endovascular vessel sealing and arrest of bleeding with a combination of balloons, covered stents, or embolic materials have also been proposed. The authors describe a case of emergent lifesaving microcoil embolization of the distal right coronary artery in a patient with uncontrollable grade III guidewire perforation resulting in cardiac tamponade. The relevant literature is reviewed and the merits and limitations of the endovascular approach are highlighted.

Ligature des artères iliaques internes face aux hémorragies obstétricales graves en milieu africain

Objectives Assess the efficiency of internal iliac arteries ligation in intractable obstetrical hemorrhage and ascertain success or failure factors. Patients and methods It was a retrospective study which concerned 159 patients who underwent internal iliac arteries ligation for persistent and severe obstetrical hemorrhage from March 1992 to February 2007. Arrest of hemorrhage after ligation with survival of the patient was considered as successful; was considered as failure, persistence of hemorrhage in spite of the ligation or patient death. Results Internal iliac arteries ligation allowed hemorrhage control in 84,3% of cases. Main etiology of hemorrhage were: uterine atony (42,8%), abruptio placentae (31,4%). Coagulation disorders and hypovolemic shock, consequences of long delay of management were identified as bad prognosis factors. Blood transfusion was also singled out as a factor likely to ameliorate prognosis, especially in hemodynamic precarious situations. Surgical complications incidence was 1,89%, represented by two internal iliac vein lesions and one ureteral section successfully repaired. Discussion and conclusion Internal iliac arteries ligation is a prerequisite treatment of severe postpartum hemorrhage. The outcome is better when it is performed precociously ( p = 0,0000003) before the happening of disseminated intra vascular coagulation ( p = 0,006), hemodynamic troubles ( p = 0,0099) and acute severe anemia ( p = 0,02). It is a good alternative to arterial embolization in Africa.

Impaired Platelet Procoagulant Mechanisms in Patients with Bleeding Disorders

Activated platelets contribute to the arrest of bleeding by forming aggregates at sites of vascular injury and by providing a surface for assembling enzyme complexes involved in fibrin formation (platelet procoagulant activity; PCA). Impairment in the latter property of platelets has been observed in some disorders of hemostasis. In Scott syndrome, there is a defect in membrane vesiculation and in the surface expression of phosphatidylserine (PS), the phospholipid that is necessary for assembling the factor VIIIa/IXa (tenase) and factor Va/Xa (prothrombinase) complexes involved in thrombin formation. A family with an isolated defect in vesiculation, but normal prothrombinase activity, has also been reported. In the Quebec platelet disorder, overexpression of the fibrinolytic enzyme urokinase-type plasminogen activator results in the degradation of alpha-granule proteins, including factor V, and a specific abnormality in platelet factor V is the basis for the prothrombinase defect in platelet factor V-New York. The impaired prothrombinase activity in patients with delta-storage pool deficiency may be due to a failure to provide sufficient amounts of secreted adenine nucleotides which, when bound to P2 purinergic receptors, are necessary to maintain the intracellular Ca (2+) levels that are required for the surface expression of PS. Platelet prothrombinase activity and thrombin potential in patients with Glanzmann thrombasthenia (GPIIb-IIIa deficiency) may be decreased, normal, or increased, depending on the experimental conditions, for reasons that are not currently clear. The most consistent platelet PCA abnormality in the Bernard-Soulier syndrome (GPIb-complex deficiency) is an abnormally short serum prothrombin time, associated with a defect in the process by which an interaction between fibrin, von Willebrand factor, and GPIb promotes PCA.

Probing Exocytosis In Blood Platelets

Exocytosis, a fundamental process for information exchange among cells including neurons, has been extensively studied based on its critical role in many physiological processes. The recent application of techniques such as microelectrochemistry has enabled measurement of individual secretion events, facilitating a mechanistic understanding of the secretion process and chemical messenger storage. In the work presented herein, microelectrochemistry methods are used to study the exocytosis process in blood platelets for the first time. Exocytosis is utilized by platelets as a signaling pathway to accomplish their role in primary hemostasis, the arrest of bleeding. Because platelet exocytosis is similar in many ways to exocytosis in neurons, platelets have been historically treated as an easily obtainable neuronal model. Our work gives the first experimental evidence of quantal secretion from platelets, resulting from exocytosis of one type of specialized granule from platelets, dense-body granules, by employing fast-scan cyclic voltammetry and amperometry at carbon-fiber microelectrodes. While cyclic voltammograms confirm that the released molecules are serotonin, amperometry provides not only the first evidence of quantal secretion of serotonin from platelets, but also a real-time record of the secretion events. Individual platelets secrete an average of ∼15 serotonin-containing granules, each with a serotonin concentration of ∼0.6M and a secretion time course of ∼7 ms. By combining experimental data with simulation results, we conclude that serotonin, along with other small molecules, is stored in the dense-body granules as a protein-free macromolecular complex rather than in a free solution state. This finding is in stark contrast to storage mechanisms proposed for other cell types where a proteinacious matrix is usually present. This work also examines the effects of variations in physiologically relevant extracellular conditions such as osmolarity, pH, temperature and cholesterol concentrationl, on serotonin secretion.This study is supported by the Searle Scholars Program.

44. New developments in lyophilized platelets for arrest of bleeding in transfusion medicine

44. New developments in lyophilized platelets for arrest of bleeding in transfusion medicine

ADAMTS-13 Has a Disulfide Bond Reduction Activity on Von Willebrand Factor

Von Willebrand factor (VWF) multimers tether platelets to subendothelium exposed at the site of vessel injury to initiate the bleeding arrest. Upon synthesized, VWF multimers are either constitutively secreted or packed into the storage granules, where they are enriched in ultra-large (UL) multimers that are active in forming spontaneous high strength bonds with the GP Ib-IX-V complex on platelets. This hyper-reactivity of ULVWF multimers is in contrast to VWF multimers circulating in plasma (pVWF) that need to be activated by modulators or high fluid shear stress to aggregate platelets. The biochemical and structural bases for the functional difference between ULVWF and pVWF multimers are not known. We have recently shown that a portion of pVWF, but not ULVWF multimers contain surface exposed free thiols in the D3 and C domains. High fluid shear stress promotes the formation of new disulfide bonds utilizing the thiols to enhance VWF binding to platelets, suggesting that the shear-induced thiol-disulfide exchange may serve as a mechanism for the shear-induced activation of pVWF multimers. ULVWF freshly secreted from endothelial cells forms string-like structures that can be elongated by pVWF multimers through a covalent means. The different thiol distribution between ULVWF and its plasma counterpart may be caused by the former being cleaved by the zinc metalloprotease ADAMTS-13 at a single peptide bond of Y1065-M1606 in the A2 domain. Here, we provide several lines of evidence to demonstrate that ADAMTS-13 also contains a reductase-like activity that plays a role in cleaving ULVWF strings under flow conditions and maintaining circulating VWF multimers in an inactive (thiol) state. First, more than 90% of pVWF non-specifically adhered to the surface of a cone-plate viscometer when pVWF was exposed to a pathological high shear stress of 100 dyn/cm2 for 3 min at 37°C. The adhesion was prevented by recombinant (r) ADAMTS-13 or a truncation mutant that lacked the catalytic domain. Second, rADAMTS-13 prevented the shear-induced thiol-disulfide exchange so that free thiols remained in pVWF after shear exposure. This activity was not blocked by 5 mM of EDTA and was detectable with the N-terminal truncated mutant, suggesting that it is independent of the VWF-cleaving activity. We further found that rADAMTS-13 was able to reduce disulfide bonds, converting the disulfide forms of sheared pVWF to the thiol forms, suggesting that ADAMTS-13 prevents the thiol-disulfide exchange by disulfide bond reduction, not a steric hindered effect. Third, ADAMTS-13 contains the surface exposed thiol(s) that is necessary for the metalloprotease to attack and break a disulfide bond. Unlike VWF multimers, these thiols remained after the metalloprotease was exposed to a pathological high shear stress of 100 dyn/cm2. Fourth, using a series of N- and C-terminal truncation mutants, we located the thiol(s) potentially involved in VWF reduction to the 2nd to 8th TSP-1 motifs and CUB-1 domain of ADAMTS-13. Finally, ethylmaleimide (NEM), which blocks free thiols, did not inhibit rADAMTS-13 to cleave pVWF multimers under static conditions and in the presence of urea and barium. NEM-treated rADAMTS-13 retained only 27.5±4.9% activity in cleaving ULVWF strings under flow conditions as compared to untreated enzyme. These data characterizes a novel mechanism that plays a regulatory role in cleaving ULVWF strings and maintaining the circulating pVWF multimers in inactive forms.

Abdominal Compartment Syndrome Complicating Paediatric Extracorporeal Life Support: Diagnostic and Therapeutic Challenges

We report three paediatric cases, and summarise the reported experience in two others, with cardiorespiratory failure requiring extracorporeal life support for which supportive pump flows could not be maintained due to abdominal compartment syndrome. In two of our patients, the mechanism of abdominal compartment syndrome was massive intra-abdominal fluid extravasation secondary to sepsis, while in the third, the mechanism was post-traumatic intra-abdominal haemorrhage. Although all three children eventually died, decompressive laparotomy and arrest of haemorrhage in the trauma patient restored venous return and enabled technically adequate extracorporeal life support. In two previously reported cases of sepsis with massive fluid resuscitation resulting in abdominal compartment syndrome, one patient died without attempted decompression, while the other patient survived after peritoneal catheter placement restored venous return. Once correctable causes of inadequate venous cannula drainage have been excluded, abdominal compartment syndrome should be considered in any patient on extracorporeal life support with a taut abdomen and reduced venous return. If abdominal compartment syndrome can be proven or is strongly suspected, there may be a role for selective decompressive laparotomy.

How Intracranial Aneurysm Rupture Damages the Brain

Intracranial aneurysm rupture causes arterial bleeding into the subarachnoid space (SAH). In the acute stage lasting around 5 minutes intracranial pressure (ICP) rises rapidly up to the level between systolic and diastolic blood pressures, which slows down the outflow of blood, facilitates clot formation in the site of rupture and leads to arrest of bleeding. Increased ICP lowers cerebral perfusion pressure, causing brain ischemia, which is unevenly distributed throughout the brain as a result of interhemispheric pressure gradients, arterial spasms and other factors. No-reflow phenomenon in the capillaries following temporary arrest or considerable slowing of circulation produces areas of hypoperfusion and reduced capacity of blood flow autoregulation scattered irregularly in the brain in the subacute stage up to 30 minutes following haemorrhage. Disturbed regional cerebral blood flow is accompanied by spots of damaged blood brain barrier resulting in brain oedema. After SAH the brain remains vulnerable to reduction of blood flow and hypoxaemia, which explains greater brain damage after secondary haemorrhage, and in some cases persistent neurological deficits or global brain dysfunction.

Anti-inflamatory effect of Bletilla striata through the inhibition of inflammatory mediators expression in Raw 264.7 cells

Bletilla striata (BS) is a Korean traditional medicinal herb for the treatment of duodenal and gastric ulcer. Also BS has an effect on arrest of bleeding. But no detailed anti-inflammatory study has been reported. In the present study, we investigated nitric oxide (NO) and prostaglandin E2 (PGE2) production by ELISA as well as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression level by western blotting in LPS-induced Raw 264.7 cells. The expression level of proinflammatory cytokines such as TNF-α, IL-1β, IL-6 and IFN-γ were detected by cytokine array. BS extract and its fractions inhibited significantly proinflammatory cytokines expression level. Also BS chloroform and ethyl acetate fractions inhibited production of NO and PGE2 as well as expression level of iNOS, COX-2 and proinflammatory cytokines in LPS-induced Raw 264.7 cells. These results suggest that BS extract and its fractions have anti-inflammatory effect through the inhibition of iNOS, COX-2 and pro-inflammatory cytokines such as TNF-α, IL-1β, IL-6 and IFN-γ.

Advances in minor oral surgery in patients with congenital bleeding disorders

Advances in minor oral surgery in patients with congenital bleeding disorders