Search

We aimed to investigate the resuscitative efficacy of hemoglobin vesicles (HbVs) as a red blood cell (RBC) substitute for the initial treatment of severe postpartum hemorrhage (PPH). Twenty-five pregnant rabbits underwent cesarean section; uncontrolled hemorrhage was induced by transecting the right uterine artery to establish a severe PPH model. During the first 30 min, all rabbits were administered 6% hydroxyethyl starch (HES) of an equivalent volume to the hemorrhage every 5 min. Thereafter, they received any of the following three isovolemic fluids for resuscitation every 5 min: RBCs with platelet-poor plasma (RBC/PPP) (n = 8), 6% HES (n = 7), or HbVs with 25% human serum albumin (n = 10). After surgical hemostasis at 60 min, survival was monitored until 12 h. No rabbits receiving only HES infusion survived beyond 6 h, whereas all rabbits receiving RBC/PPP transfusion survived. The rabbits receiving HbV infusion showed significantly higher mean arterial pressure and hemoglobin levels than the HES-receiving rabbits, and 8 of 10 rabbits survived for 6 h. The HbV group showed significantly higher survival than the HES group but worse survival than the RBC/PPP group. In conclusion, HbV infusion for severe PPH effectively prevents lethal hemorrhagic shock in a pregnant rabbit model.

Backgrounds Intravenous transfusion sometimes encounters difficulty under prehospital conditions when peripheral vessels are collapsed and inaccessible. We investigated whether the cellular type hemoglobin-based oxygen carriers (Hemoglobin Vesicles: HbVs) allow intraosseous administration into blood circulation for the resuscitation of rabbits with severe hemorrhagic shock. Study design and methods New Zealand white rabbits (2.5 kg average) were set in severe hemorrhagic shock [mean arterial pressure (MAP): 21 ± 2 mm Hg, Hb 5.1 ± 0.8 g/dL]. Immediately thereafter, 12 mL/kg of HbVs, 5% human serum albumin (HSA), autologous whole blood (WB), stored red blood cells (RBCs) or 36 mL/kg of Lactated Ringer's (LR) were intraosseously transfused, followed by an additional intraosseous transfusion with 8 mL/kg of HSA (following HbV, HSA or stored RBC transfusion), or WB or 24 mL/kg of LR (following LR transfusion), respectively. Results Intraosseous transfusion of HbVs increased MAP (48 ± 9 mm Hg) and improved hypohemoglobinemia (7.1 ± 0.6 g/dL) as well as WB or RBC transfusion. In contrast, neither HSA nor LR improved hemodynamics or Hb levels. Seven out of 10 rabbits receiving HbVs survived for 24 hours, while only one out of 10 rabbits receiving LR survived (WB and RBC; 100% survivals, HSA; 30% survival). Conclusions Intraosseous infusion of HbVs might be an effective initial treatment to maintain hemodynamics during acute hemorrhagic shock. This approach could be used in emergency situations in which access to peripheral vessels is difficult.

Although an enormous number of animal studies on blast-induced traumatic brain injury (bTBI) have been conducted, there still remain many uncertain issues in its neuropathology and mechanisms. This is partially due to the complex and hence difficult experimental environment settings, e.g., to minimize the effects of blast winds (tertiary mechanism) and to separate the effects of brain exposure and torso exposure. Since a laser-induced shock wave (LISW) is free from dynamic pressure and its energy is spatially well confined, the effects of pure shock wave exposure (primary mechanism) solely on the brain can be examined by using an LISW. In this study, we applied a set of four LISWs in the impulse range of 15–71 Pa·s to the rat brain through the intact scalp and skull; the interval between each exposure was ~5 s. For the rats, we conducted locomotor activity, elevated plus maze and forced swimming tests. Axonal injury in the brain was also examined by histological analysis using Bodian silver staining. Only the rats with exposure at higher impulses of 54 and 71 Pa·s showed significantly lower spontaneous movements at 1 and 2 days post-exposure by the locomotor activity test, but after 3 days post-exposure, they had recovered. At 7 days post-exposure, however, these rats (54 and 71 Pa·s) showed significantly higher levels of anxiety-related and depression-like behaviors by the elevated plus maze test and forced swimming test, respectively. To the best of the authors' knowledge, there have been few studies in which a rat model showed both anxiety-related and depression-like behaviors caused by blast or shock wave exposure. At that time point (7 days post-exposure), histological analysis showed significant decreases in axonal density in the cingulum bundle and corpus callosum in impulse-dependent manners; axons in the cingulum bundle were found to be more affected by a shock wave. Correlation analysis showed a statistically significant correlation between the depression like-behavior and axonal density reduction in the cingulum bundle. The results demonstrated the dependence of behavior deficits and axonal injury on the shock wave impulse loaded on the brain.

Damage control resuscitation improves patient outcomes after severe hemorrhage and coagulopathy. However, effective hemostasis methods for these critical situations are lacking.We evaluated the hemostatic efficacy of fibrinogen γ-chain (HHLGGAKQAGDV, H12)-coated, adenosine-diphosphate (ADP)-encapsulated liposomes (H12-[ADP]-liposomes) in thrombocytopenic rabbits with hemorrhagic shock.Acute thrombocytopenia (80%) was induced in rabbits that also received mesenteric vessel injury, leading to hemorrhagic shock. Five minutes after injury, subjects received intravenous bolus injection with H12-(ADP)-liposomes (20 mg/kg), followed by isovolemic transfusion with stored red blood cells (RBCs)/platelet poor plasma (PPP) (RBC:PPP = 1:1 [vol/vol]), or lactated Ringer solution every 5 min to compensate blood loss. One group received H12-(phosphate buffered saline [PBS]) liposomes followed by RBC/PPP. Additional groups were received isovolemic transfusion with RBC/platelet rich plasma (PRP) (RBC:PRP = 1:1 [vol/vol]), RBC/PPP, PPP alone, or lactated Ringer solution.Treatment with H12-(ADP)-liposomes followed by RBC/PPP transfusion and RBC/PRP transfusion effectively stopped bleeding in all thrombocytopenic rabbits. In contrast, three of 10 rabbits treated with RBC/PPP failed hemostasis, and no rabbits receiving lactated Ringer solution stopped bleeding or survived. Twenty-four hours after hemorrhage, 80% of rabbits receiving H12-(ADP)-liposome followed by RBC/PPP transfusion survived and 70% of rabbits receiving RBC/PRP transfusion also survived, although RBC/PPP-transfused rabbits showed 40% survival. Rabbits receiving H12-(ADP)-liposomes followed by lactated Ringer solution showed a transient hemostatic potential but failed to survive. H12-(PBS)-liposomes showed no beneficial effect on hemostasis. Neither the PPP group nor the lactated Ringer group survived.H12-(ADP)-liposome treatment followed by RBC/PPP may be effective in lethal hemorrhage after mesenteric vessel injury in coagulopathic rabbits.

Background: Recently, 5-aminolevulinic acid (ALA) has been reported to modulate inflammatory development via an antioxidant effect. Hence, the aim of this study was to determine the anti-atherosclerotic effect of ALA. Methods and Results: Low-density lipoprotein (LDL) receptor knockout mice were fed the following diets for 24 weeks: normal diet (n=6); 1.25% cholesterol diet (high-cholesterol diet, HCD; n=7); HCD+ALA (46 mg/kg/day; n=10); and HCD+ezetimibe (5 mg/kg/day; n=10). At 40 weeks, HCD+ALA had reduced LDL cholesterol (320±68 vs. 379±49 mg/dL), triglyceride (141±44 vs. 195±49 mg/dL) and oxidized LDL (380±40 vs. 422±64 pg/mL) compared with HCD only. En face lesion area for the entire aortic surface was significantly smaller in mice that received HCD+ALA than in mice that received only HCD (32±5% vs. 39±4%, P

Objective. To investigate the resuscitative efficacy of haemoglobin vesicles (HbVs) for severe postpartum haemorrhage (PPH) using pregnant rabbits. Design: Animal research study Setting: Animal laboratory, National Defense Medical College, Japan Population: Twenty-five female New Zealand white rabbits at late gestation Methods. Pregnant rabbits underwent caesarean section; uncontrolled haemorrhage was induced by transecting the uterine artery to establish a severe PPH model. During the first 30 min (or until the bleeding volume reached 100 mL), all rabbits received 6% hydroxyethyl starch (HES) infusion. Thereafter, rabbits received any of the three isovolemic fluid resuscitations every 5 min: red blood cells (RBCs) with platelet-poor plasma (RBC/PPP) (vol/vol=1:1, n=8), 6% HES (n=7), or HbVs with 25% human serum albumin (vol/vol=4:1, n=10). After 60 min (or when the bleeding volume reached 200 mL), we performed surgical haemostasis and monitored the rabbit survival for 12 hours. Main Outcome Measures: Survival time for severe postpartum haemorrhage Results. During the first 30 min, all rabbits showed severe anaemia (Hb

Background Hemoglobin vesicles have been developed as artificial oxygen carriers, and they have the potential to serve as a substitute for red blood cell transfusion. Objective To evaluate the efficacy of hemoglobin vesicle infusion for initial treatment instead of red blood cell transfusion in rabbits with massive obstetric hemorrhage. Materials and Methods Pregnant New Zealand white rabbits (28th day of pregnancy; normal gestation period 29-35 days) underwent uncontrolled hemorrhage to induce shock by transecting the right mid-artery and concomitant vein in the myometrium. Subsequently, rabbits received isovolemic fluid resuscitation through the femoral vein with an equivalent volume of hemorrhage every 5 min. Resuscitative infusion regimens included 5% human serum albumin (n=6), stored washed red blood cells with plasma (vol/vol = 1:1, n=5), and hemoglobin vesicle with 5% human serum albumin (vol/vol = 4:1, n=5). Sixty minutes after the start of bleeding, rabbits received surgical hemostasis by ligation of the bleeding vessels and then were monitored for survival until 24 h. Results During fluid resuscitation, hemoglobin vesicle infusion as well as red blood cell transfusion maintained mean arterial pressure > 50 mmHg, Hb concentration > 9 g/dL, and prevented the elevation of plasma lactate. In contrast, resuscitation with 5% human serum albumin alone could not prevent hemorrhagic shock as evidenced by a low mean arterial pressure (40 mmHg), low Hb concentration (2 g/dL), and a marked elevation of plasma lactate. All animals in the red blood cell group and the hemoglobin vesicle group survived more than 8 h, whereas all animals in the 5% human serum albumin group died within 8 h. Conclusions HbV infusion may be effective in the initial management of massive obstetric hemorrhage.

Fibrinogen γ-chain peptide-coated, adenosine 5′-diphosphate (ADP)-encapsulated liposomes (H12-ADP-liposomes) are a potent haemostatic adjuvant to promote platelet thrombi. These liposomes are lipid particles coated with specific binding sites for platelet GPIIb/IIIa and encapsulating ADP. They work at bleeding sites, facilitating haemostasis by promoting aggregation of activated platelets and releasing ADP to strongly activate platelets. In this study, we investigated the therapeutic potential of H12-ADP-liposomes on post-cardiopulmonary bypass (CPB) coagulopathy in a preclinical setting. We created a post-CPB coagulopathy model using male New Zealand White rabbits (body weight, 3 kg). One hour after CPB, subject rabbits were intravenously administered H12-ADP-liposomes with platelet-rich plasma (PRP) collected from donor rabbits (H12-ADP-liposome/PRP group, n = 8) or PRP alone (PRP group, n = 8). Ear bleeding time was greatly reduced for the H12-ADP-liposome/PRP group (263 ± 111 s) compared with the PRP group (441 ± 108 s, p

Background: We developed a Hemoglobin vesicles (HbV), which are artificial substitute for Red blood cells (RBCs). Objective: To evaluate the efficacy of HbV for alternative treatment instead of RBCs transfusion in rabbits with hemorrhagic shock due to post-partum hemorrhage. Methods: New Zealand white rabbits at late gestation underwent uncontrolled hemorrhagic shock by transecting a right mid-artery in the myometrium, after cesarean section of right side uterus. Initially, in the simulated ordinal treatment of bleeding, rabbits received colloid fluids (Voluven®) through an femoral vein with equivalent volume of the bleeding every 5 minutes. Once blood loss achieved 100ml, animals subsequently faced on critical hemorrhagic situation, where mean arterial pressure (MAP) reduced to approximately 48mmHg. They were randomly divided into three isovolemic resuscitation regimens: continuing colloid fluid resuscitation (n=4); transfusion of autologous washed RBCs with plasma (n=4); HbV infusion combining 5% human serum albumin (n=4). After 60 minutes of bleeding, all animals underwent surgical control of bleeding and cesarean section of left side uterus. Results: At the point of critical hemorrhagic situation, Hb concentration reduced to 4.8 g/dl. At the end of resuscitation, HbV infusion regained MAP and restored Hb concentration as well as RBCs transfusion, besides colloid fluid resuscitation exaggerated the severe hemorrhagic shock as shown in the table. Conclusions: HbV treatment may be effective in the management of post-partum hemorrhagic shock.

Background: We developed a Hemoglobin vesicle (HbV) and which is an artificial substitute for Red blood cells (RBCs). Objective: To evaluate the efficacy of intraosseous HbV transfusion for alternative treatment instead of massive RBCs transfusion in rabbits with hemorrhagic shock. Methods: Hypohemoglobinemia (Hb 5.0 ± 0.7 g/dl) was induced in rabbits by blood withdrawal (70% of total blood volume) and half compensative infusion of normal saline (35% of total blood volume), which resulted severe hemorrhagic shock (mean arterial pressure 21 ± 2 mmHg). Immediately, shortage of the blood volume (35% of total blood volume) was intraosseously infused of lactate ringer (n=8), 5% human serum albumin (n=10) or HbV with 5% human serum albumin (3:2=vol: vol) (n=8). During the experiment hemodynamics and blood cell counts were measured with time. Results: Mean arterial pressure immediately recovered (44 ± 11 mmHg), improving hypohemoglobinemia (7.1 ± 0.6 g/dl) by administration with HbV, although rabbits receiving 5% Albumin and lactate ringer never improved hemodynamics and hypohemoglobinemia. (33 ± 7 mmHg / 3.4 ± 0.4 g/dl, 26 ± 4 mmHg / 4.5 ± 0.4 g/dl, p < 0.05 vs HbV group, respectively) As a result, 75% of rabbits receiving HbV survived after 24hours, while half of rabbits with 5% Albumin were dead within 18hours and all rabbits with lactate ringer were dead within 6hours. Conclusions: Intraosseous infusion of HbV effectively restore the Hb and maintain the hemodynamics for acute hemorrhagic shock in the difficult situation to get blood access.

We have developed hemoglobin vesicles (HbVs) as a substitute for red blood cells (RBCs). We investigated the efficacy of HbV transfusion in the treatment of massive hemorrhage in rabbits in the setting of thrombocytopenic coagulopathy, focusing on the efficacy of hemostasis by subsequent platelet transfusion.Thrombocytopenic coagulopathy was induced in rabbits by repeated blood withdrawal and isovolemic retransfusion of autologous RBC (platelet counts45,000/μL). A penetrating liver injury was then made. For 30 min, bleeding volume was measured every 10 min, after which subjects were transfused with an equivalent volume of stored RBC, HbV, or platelet poor plasma (PPP) to compensate for blood loss, simulating initial prehospital resuscitation. Thereafter, we transfused platelet rich plasma (PRP) to stop bleeding, which simulated inhospital resuscitation.During the initial resuscitation, the HbV group was similar to the RBC group (but not the PPP group) in their hemodynamics and tissue circulation/oxygenation as assessed by plasma lactate levels. All rabbits showed similar bleeding volumes (20-30 mL) in this period. HbV-transfused rabbits sustained hemoglobin levels, but showed lower hematocrit levels compared with RBC-transfused rabbits. Subsequent PRP transfusion effectively stopped bleeding in all RBC-transfused rabbits (6/6) and most HbV-transfused rabbits (7/8) but not PPP-transfused rabbits (2/8). In addition, 83% of RBC-transfused rabbits and 75% of HbV-transfused rabbits survived for 24 h, although no PPP-transfused rabbits survived. HbV transfusion did not scavenge nitric oxide in rabbits.HbV transfusion effectively rescued rabbits from severe hemorrhage with coagulopathy, without disturbing hemostasis after the platelet transfusion. HbV transfusion may be practical and useful in prehospital resuscitation.

Background We evaluated the hemostatic efficacy of H12-(adenosine 5′-diphosphate [ADP])-liposomes in the setting of active liver bleeding in rabbits with dilutional thrombocytopenia after massive transfusion. Study Design and Methods Acute thrombocytopenia (platelet [PLT] count

Gadolinium(III) ion (Gd(3+)) complexes are widely used as contrast agents in magnetic resonance imaging (MRI), and many attempts have been made to couple them to sensor moieties in order to visualize biological phenomena of interest inside the body. However, the low sensitivity of MRI has made it difficult to develop practical MRI contrast agents for in vivo imaging. We hypothesized that practical MRI contrast agents could be designed by targeting a specific biological environment, rather than a specific protein such as a receptor. To test this idea, we designed and synthesized a Gd(3+)-based MRI contrast agent, 2BDP3Gd, for visualizing atherosclerotic plaques by linking the Gd(3+)-complex to the lipophilic fluorophore BODIPY to stain lipid-rich environments. We found that 2BDP3Gd was selectively accumulated into lipid droplets of adipocytes at the cellular level. Atherosclerotic plaques in the aorta of Watanabe heritable hyperlipidemic (WHHL) rabbits were clearly visualized in T1-weighted MR images after intravenous injection of 2BDP3Gd in vivo.

Sympathetic nerve activity in essential hypertension, which accounts for 90% of all hypertension cases, is in general thought to be elevated regardless of whether there is salt sensitivity or insensitivity. The cause is thought to be an abnormality in the sympathetic center. On the other hand, neuronal nitric oxide synthase-expressing neurons that function to inhibit the sympathetic center are clearly activated in the salt-sensitive hypertensive Dahl rat model. How is this related to sympathetic hyperactivity and hypertension? Also, how is hypertension associated with peripheral vessel contractility and renal function? Human life is supported by the body's various essential functions. The circulatory system links all these functions into one system that cannot be separated. Blood pressure is the driving force of this circulatory system, and both the central and peripheral demands determine the output. We examined the ‘mismatch' between these two sides and its association with hypertension.

Subdural effusion sometimes occurs during neurosurgery after opening the Sylvian fissure, due to cerebrospinal fluid (CSF) leakage from the torn arachnoid membrane. Unexpected bleeding from the fragile bridging veins may also result from brain retraction. Neurosurgeons must always watch carefully for these complications during surgery. To prevent such complications, we have attempted the clinical application of a polysaccharide nanosheet that is semi-absorbent and has a potent physical adhesive strength to investigate its therapeutic utility for arachnoid plasty and enhancement of bridging vein tensile strength in Sprague–Dawley rats. The use of overlapping nanosheets completely prevented CSF leakage from injured arachnoid membranes in the cerebral cortex. No inflammatory infiltration was observed on the cerebral surface after 6 months of follow up. In addition, the use of nanosheet bandages significantly reinforced venous tensile strength. This reinforcement increased with the number of overlaid nanosheets. We report that polysaccharide nanosheets can be used for arachnoid plasty without chemical bonding agents and for reinforcement of venous tensile strength in rat vessels. Nanosheets may be an effective neurosurgical tool.

Objective To investigate the efficacy of multioverlapping therapy using a polysaccharide nanosheet having 75-nm thickness for sealing and stopping massive venous hemorrhage. Methods The hydrostatic durability of the polysaccharide nanosheet was evaluated in vitro when secured to an incised silicon tube. For in vivo studies, the inferior vena cava (IVC) of rabbits was cut longitudinally, and multiple polysaccharide nanosheets were overlapped onto the injured IVC. Results The mechanical hydrostatic durability of the nanosheets was gradually augmented by an increasing number of multilayered nanosheets in vitro. This durability was saturated at 80 ± 6 mm Hg by four layers of nanosheets, which was robust enough to seal injured vessel walls of the large IVC. Multioverlapping therapy using nanosheets effectively sealed and stopped bleeding from the injured IVC in vivo. One month later, no inflammatory tissue response was observed around the nanosheet attachment sites of the IVC, while conventional suturing repair in control rabbits showed a severe inflammatory response around the sutured area. Conclusions The multioverlapping therapy using the polysaccharide nanosheets will effectively stop massive venous bleeding without adverse effects in the immediate or chronic postoperative setting.

Background Composition of atherosclerotic arterial walls is rich in lipids such as cholesterol, unlike normal arterial walls. In this study, we aimed to utilize this difference to diagnose atherosclerosis via multispectral fluorescence imaging, which allows for identification of fluorescence originating from the substance in the arterial wall. Methods The inner surface of extracted arteries (rabbit abdominal aorta, human coronary artery) was illuminated by 405 nm excitation light and multispectral fluorescence images were obtained. Pathological examination of human coronary artery samples were carried out and thickness of arteries were calculated by measuring combined media and intima thickness. Results The fluorescence spectra in atherosclerotic sites were different from those in normal sites. Multiple regions of interest (ROI) were selected within each sample and a ratio between two fluorescence intensity differences (where each intensity difference is calculated between an identifier wavelength and a base wavelength) from each ROI was determined, allowing for discrimination of atherosclerotic sites. Fluorescence intensity and thickness of artery were found to be significantly correlated. Conclusions These results indicate that multispectral fluorescence imaging provides qualitative and quantitative evaluations of atherosclerosis and is therefore a viable method of diagnosing the disease. Electronic supplementary material The online version of this article (doi:10.1186/s12938-016-0220-z) contains supplementary material, which is available to authorized users.

Fibrinogen γ-chain (dodecapeptide HHLGGAKQAGDV)-coated adenosine 5'-diphosphate-encapsulated liposomes can accumulate via dodecapeptide HHLGGAKQAGDV interactions at bleeding sites where they release adenosine 5'-diphosphate that is rapidly metabolized to adenosine, which has tissue-protective effects. We investigated the efficacy of fibrinogen γ-chain (dodecapeptide HHLGGAKQAGDV)-coated adenosine 5'-diphosphate-encapsulated liposomes to treat blast lung injury, with a focus on adenosine signaling.Controlled animal study.University research laboratory.Adult male C57BL/6 mice.Mice were pretreated with fibrinogen γ-chain (dodecapeptide HHLGGAKQAGDV)-coated adenosine 5'-diphosphate-encapsulated liposomes, dodecapeptide HHLGGAKQAGDV-(phosphate-buffered saline)-liposomes, adenosine 5' diphosphateliposomes, or phosphate-buffered saline-liposomes. Five minutes after treatment the mice received a single laser-induced shock wave (1.8 J/cm) that caused lethal blast lung injury, and their survival times and lung injuries were then assessed. We also evaluated the therapeutic effect of posttreatment with fibrinogen γ-chain (dodecapeptide HHLGGAKQAGDV)-coated adenosine 5'-diphosphate-encapsulated liposomes or H12-(phosphate-buffered saline)-liposomes 1 minute after laser-induced shock wave exposure. To examine the effect of adenosine signaling, adenosine A2A receptor (ZM241385) or adenosine A2B receptor (PSB 1115) antagonists were administered to the mice 1 hour before the pretreatment with fibrinogen γ-chain (dodecapeptide HHLGGAKQAGDV)-coated adenosine 5'-diphosphate-encapsulated liposomes that was followed by laser-induced shock wave exposure.Pre- and posttreatment with fibrinogen γ-chain (dodecapeptide HHLGGAKQAGDV)-coated adenosine 5'-diphosphate-encapsulated liposomes significantly increased mouse survival [fibrinogen γ-chain (dodecapeptide HHLGGAKQAGDV)-coated adenosine 5'-diphosphate-encapsulated liposomes: 58% survival vs H12-(phosphate-buffered saline)-liposomes: 8%; p0.05 (posttreatment)] and mitigated pulmonary tissue damage/hemorrhage and neutrophil accumulation after laser-induced shock wave exposure. fibrinogen γ-chain (dodecapeptide HHLGGAKQAGDV)-coated adenosine 5'-diphosphate-encapsulated liposomes accumulated at pulmonary vessel injury sites after laser-induced shock wave exposure with both pre- and posttreatment. Furthermore, pretreatment with fibrinogen γ-chain (dodecapeptide HHLGGAKQAGDV)-coated adenosine 5'-diphosphate-encapsulated liposomes reduced albumin and macrophage inflammatory protein-2 levels in bronchoalveolar lavage fluid. Although fibrinogen γ-chain (dodecapeptide HHLGGAKQAGDV)-coated adenosine 5'-diphosphate-encapsulated liposomes pretreatment did not affect blood coagulation activity in the injured mice, its beneficial effect on blast lung injury was significantly abrogated by A2A or A2B adenosine receptor antagonists (A2A antagonist: 17% survival; A2B antagonist: 33% vs dimethyl sulfoxide control: 80%; p0.05, respectively).Fibrinogen γ-chain (dodecapeptide HHLGGAKQA GDV)-coated adenosine 5'-diphosphate-encapsulated liposomes may be effective against blast lung injury by promoting tissue-protective adenosine signaling and could represent a novel controlled-release drug delivery system.

Background Blast lung injuries (BLI) caused by blast waves are extremely critical in the prehospital setting, and hypotension is thought to be the main cause of death in such cases. The present study aimed to elucidate the pathophysiology of severe BLI using laser-induced shock wave (LISW) and identify the initial treatment. Methods The current investigation comprised two parts. For the validation study, mice were randomly allocated to groups that received a single shot of 1.2, 1.3, or 1.4 J/cm2 LISW to both lungs. The survival rates, systolic blood pressure (sBP), heart rate (HR), peripheral oxyhemoglobin saturation (SpO2), and shock index were monitored for 60 min, and lung tissues were analyzed histopathologically. The study evaluated the effects of catecholamines as follows. Randomly assigned mice received 1.4 J/cm2 LISW followed by the immediate intraperitoneal administration of dobutamine, noradrenalin, or normal saline. The primary outcome was the survival rate. Additionally, sBP, HR, SpO2, and the shock index were measured before and 5 and 10 min after LISW, and the cardiac output, left ventricular ejection fraction, and systemic vascular resistance (SVR) were determined before and 1 min after LISW. Results The triad of BLI (hypotension, bradycardia, and hypoxemia) was evident immediately after LISW. The survival rates worsened with increasing doses of LISW (100 % in 1.2 J/cm2 vs. 60 % in 1.3 J/cm2, 10 % in 1.4 J/cm2). The histopathological findings were compatible with those of human BLI. The survival rate in LISW high group (1.4 J/cm2) was highest in the group that received noradrenalin (100 %), with significantly elevated SVR values (from 565 to 1451 dyn s/min5). In contrast, the survival rates in the dobutamine and normal saline groups were 40 and 10 %, respectively, and the SVR values did not change significantly after LISW in either group. Conclusions The main cause of death during the initial phase of severe BLI is hypotension due to the absence of peripheral vasoconstriction. Therefore, the immediate administration of noradrenalin may be an effective treatment during the initial phase of severe BLI.

We report here two cases of Wenckebach atrioventricular (AV) block in which apparent AV junctional escape was observed, but most likely resulted from markedly slow conduction through the slow pathway of dual AV junctional pathways. In these cases, it seems that a blocked P-wave was followed by an AV junctional escape beat. However, a blocked P-wave occasionally failed to be followed by an escape beat, and the RR interval containing the blocked P-wave was markedly longer than the above escape interval. In one case, apparent AV junctional escape beats with aberrant ventricular conduction were found, and QRS complexes of the same configuration were also found without the preceding ventricular pause. This strengthens the possibility that apparent AV junctional escape occurred because of markedly slow conduction through the slow AV pathway.

The Holter monitor electrocardiograms were taken from 2 patients with intermittent Wolff-Parkinson-White syndrome. In these patients, when the heart rate was increased, accessory-pathway block on alternate beats was found and was maintained for a considerably long period. In one patient, when accessory-pathway block on alternate beats was found, a ventricular extrasystole occurred. After the long compensatory pause after that extrasystole, a sinus impulse was blocked in the accessory pathway, showing that the effective refractory period of the accessory pathway is markedly long. These findings strongly suggest that alternate sinus impulses fell in the supernormal period of the accessory pathway. An attempt was made to explain the mechanism of accessory-pathway block on alternate beats by using the concept of supernormal conduction in the accessory pathway, in the same way as in bundle-branch block on alternate beats.

Composition of atherosclerotic arterial walls is rich in lipids such as cholesterol; unlike normal arterial walls. In this study, we aimed to utilize this difference to diagnose atherosclerosis via multispectral imaging, which allows for identification of fluorescence originating from the substance in the arterial wall. The inner surface of extracted arteries (rabbit abdominal aorta, human coronary aorta) was illuminated by an excitation light and multispectral fluorescence images were obtained. The fluorescence spectra in atherosclerotic sites were shown to be different from those in normal sites. A ratio of fluorescence intensity at a wavelength of two significant differences was then calculated for each pixel and ratio images were reconstructed. As a result, we succeeded in “disease mapping”, by which atherosclerotic sites can be discriminated from normal sites. The differences in fluorescence spectra may be attributed to the differences in fluorophores contained in the intima/media of the artery.

Background: Fibrinogen gamma-chain (HHLGGAKQAGDV, H12)-coated, adenosine-diphosphate (ADP)-encapsulated liposomes [H12-(ADP)-liposomes] that accumulate at bleeding sites via interaction with activated platelets via GPIIb/IIIa and release ADP. Objective: To elucidate the effect of H12-ADP-liposomes and its mechanisms on the lethal pulmonary hemorrhage following blast injury. Methods: Mice were pretreated with H12-ADP-liposomes (n=14), ADP-liposomes (n=10), PBS-liposomes (n=10) or normal saline (n=14). A single shot of laser induced shock wave (LISW, 1.8 J/cm2) caused lethal diffuse alveolar hemorrhage in mice. Furthermore, to examine the adenosine effect of H12-ADP-liposomes, adenosine A2A receptor antagonist (ZM241385, n=6) or adenosine A2B receptor antagonist (PSB 1115, n=6) was administered 1 hr before the H12-ADP-liposomes + LISW procedures. Among them, the acute prognosis (survival rates) and pathological injury score (blending area) were compared. The levels of albumin and MIP-2 in the bronchoalveloral lavage fluid (BALF) were measured after LISW in each group. Results: H12-ADP-liposomes significantly improved mouse survival (Figure) and reduced the pathological injury score than normal saline (35 vs 40, p=0.004, n=5). H12-ADP-liposomes reduced the albumin leakage (0.8 vs 1.3 mg/ml, p=0.03, n=6) and MIP-2 levels in the BALF (74 vs 355 pg/ml, p Conclusions: H12-ADP-liposomes may be effective for acute blast lung injury, functioning hemostasis and organ protection via anti-inflammatory purinergic signaling.

We evaluated the hemostatic efficacy of H12-(adenosine 5'-diphosphate [ADP])-liposomes in the setting of active liver bleeding in rabbits with dilutional thrombocytopenia after massive transfusion.Acute thrombocytopenia (platelet [PLT] count 50 × 10(9) /L) was induced in rabbits by repeated blood withdrawal and isovolemic transfusion of autologous washed red blood cells. Liver hemorrhage was initiated by a penetrating liver injury. Subsequently, the animals received tamponade treatment for the liver hemorrhage for 5 minutes and were intravenously administered H12-(ADP)-liposomes with PLT-poor plasma (PPP), PLT-rich plasma (PRP), PPP alone, H12-(phosphate-buffered saline [PBS])-liposome/PPP, or H12-(ADP)-liposomes/PPP plus fibrinogen concentrate during the tamponade.Administration of H12-(ADP)-liposomes/PPP rescued 60% of the rabbits from the liver hemorrhage; PRP administration rescued 50%. In contrast, rabbits receiving PPP or H12-(PBS)-liposome/PPP achieved only 10 or 17% survival, respectively, for the first 24 hours. H12-(ADP)-liposomes/PPP as well as PRP consistently reduced bleeding volumes and shortened clotting times (CTs) in comparison to PPP administration. Specifically, bleeding volumes in the initial 5 minutes averaged 11 mL (H12-(ADP)-liposomes/PPP) and 17 mL (PRP) versus 30 mL (PPP; p 0.05); CTs averaged 270 and 306 seconds versus 401 seconds (p 0.05). H12-(ADP)-liposomes were observed at the bleeding site with thrombus formation, suggesting an induction of thrombi. Neither macro- nor microthrombi were detected in the lung, kidney, spleen, or liver in rabbits treated with H12-(ADP)-liposomes. Supplementation of fibrinogen to H12-(ADP)-liposomes/PPP did not significantly improve rabbit survival.H12-(ADP)-liposomes might be a safe and effective therapeutic tool during damage control surgery for trauma patients with acute thrombocytopenia and massive bleeding.

Large, bilateral central pulmonary thromboemboli (PTE) led to cor pulmonale and severe hypoxemia in a patient who had undergone Hardy's operation. After several unsuccessful efforts (thrombolysis using a percutaneous catheter and aspiration of the emboli), mechanical clot fragmentation using a percutaneous transluminal angioplasty (PTA) balloon was attempted. This procedure was successful, resulting in a decrease in pulmonary artery pressure from 58/22 (mean 34) mmHg to 20/10 (mean 13) mmHg together with an increase in aortic pressure from 64/36 (mean 45) mmHg to 112/60 (mean 77) mmHg. Thus, mechanical clot fragmentation using a PTA balloon is a promising method for reducing pulmonary artery pressure and increasing aortic pressure in patients with acute PTE. (Jpn Circ J 1997; 61: 531 - 535)

In essential hypertension, peripheral sympathetic nerve activity is generally thought to be increased regardless of salt sensitivity or insensitivity. Recent reports suggest that the cause may be abnormal central nervous system enhancement. However, other several reports have shown that a central sympathetic inhibitory system, the neuronal nitric oxide synthase system, may be strongly enhanced in salt-sensitive hypertensive Dahl rats, an animal model of salt-sensitive hypertension. These two facts lead to questions what happens finally in peripheral sympathetic activity and what is the relationship between sympathetic nerves and hypertension. In this review, we will show evidences for enhancement of central sympathetic inhibitory system, putative cause for up-regulation of central neuronal nitric oxide synthase system, and a role of its function, then lastly we consider the relationship between hypertension and sympathetic nerves in a rat model, with a focus on salt-sensitive hypertension.

The aims of the present study were to determine the mechanism underlying enhanced neuronal nitric oxide synthase (nNOS) activity in the brain of hypertensive Dahl salt-sensitive (DSS) rats and the consequences of enhanced nNOS activity. Male DSS rats were fed either a regular (0.4% NaCl) or high-salt (8% NaCl) diet, with or without 0.25% nifedipine, for 4 weeks. The effects of nifedipine, which lowers blood pressure peripherally, on central nNOS were determined by measuring nNOS activity, as well as the number of nNOS-positive neurons in the brain stem and diencephalon. The effects of chronic (12 days) infusion of 7 μg (0.5 μL/h, i.c.v.) S-methyl-L-thiocitrulline (SMTC; a stereoselective competitive nNOS inhibitor) on mean arterial pressure were assessed in conscious DSS rats using a radiotelemetry system. In addition, the number of central nNOS-positive neurons was compared between DSS and salt-insensitive Sprague-Dawley rats. Normalization of blood pressure by nifedipine attenuated the increase in nNOS activity in the brain stem of DSS rats. Chronic i.c.v. infusion of SMTC further enhanced hypertension in DSS rats. Feeding of a high-salt diet increased nNOS-positive neurons in the lateral parabrachial nucleus, rostral ventrolateral medulla and nucleus tractus solitarius of DSS compared with Sprague-Dawley rats, whereas nNOS-positive neurons in the paraventricular nucleus remained downregulated in DSS rats. The results of the present study suggest that hypertension, rather than a high-salt diet, increases central nNOS activity in hypertensive DSS rats to buffer high blood pressure. However, this compensatory response may be insufficient to relieve salt-induced hypertension.

The purpose of this study is to investigate the vascular wall with a thermally self-regulating, cylindrical stent made of a low Curie temperature ferromagnetic alloy. Physiologic saline was circulated in the silicone model vessel implanted with the stent. The stent-temperature remained nearly constant for variable saline flows, saline temperatures, and magnetic flux densities. Stent implants of this type in human blood vessels could potentially enable thermotherapy and temperature determination without catheterization.

To determine continuous body temperature distribution, an inexpensive temperature mapping system was developed using a deep body thermometer adopting the finite-element method. A stripe with 16 thermocouples was wrapped around the waist of rats to measure body surface temperatures (the boundary conditions). The abdominal deep temperature of the rats was measured from the dorsum using the thermal compensation probe of a deep body thermometer. The abdominal temperature of the rats was mapped by solving a heat conduction equation using surface and deep temperatures obtained in real time. The temperature measured with a thermocouple inserted into the abdominal centre of the rats correlated well with the calculated temperature ( r = 0.93, p < 0.01 ). The system is low cost and simple to use compared with the magnetic resonance temperature mapping system. Our temperature mapping system could potentially result in improved management of patients in critical care medicine.

Mean arterial pressure fluctuates depending on physical or psychological activity, but should be stable at rest at around 100 mmHg throughout an entire life in human. The causes of hypertension and the blood pressure regulation mechanisms have been discussed for a long time, and many aspects have recently become more clear. Circulatory shock or short-term hypotension can be treated based on what is now known, but chronic hypertension is still difficult to treat thoroughly. The exact mechanisms for long-term blood pressure regulation have yet not been elucidated. Neuro–humoral interaction has been suggested as one of the mechanisms. Then, from the 1990s, paracrine hormones like nitric oxide or endothelins have been extensively researched in order to develop endothelial local control mechanisms for blood pressure, which have some relationships to long-term control. Although these new ideas and mechanisms are newly developed, no clear explanation for long-term control has yet been discussed, except for renal abnormality. Recently, a central set-point theory has begun to be discussed. This review will discuss the mechanisms for long-term blood pressure control, based on putative biological missions of circulatory function for life support.

The 2009 pandemic H1N1 influenza A virus spread quickly worldwide in 2009. Since most of the fatal cases were reported in developing countries, rapid and accurate diagnosis methods that are usable in poorly equipped laboratories are necessary. In this study, a mobile detection system for the 2009 H1N1 influenza A virus was developed using a reverse‐transcriptase loop‐mediated isothermal amplification (RT‐LAMP) kit with a disposable pocket‐warmer as a heating device (designated as pwRT‐LAMP). The pwRT‐LAMP can detect as few as 100 copies of the virus—which is nearly as sensitive as real‐time reverse‐transcription polymerase chain reaction (RT‐PCR)—and does not cross‐react with RNA of seasonal influenza viruses. To evaluate the usefulness of the pwRT‐LAMP system, nasal swab samples were collected from 56 patients with flu‐like symptoms and were tested. Real‐time RT‐PCR confirmed that the 2009 H1N1 influenza A virus was present in 27 of the 56 samples. Of these 27 positive samples, QuickVue Influenza A + B immunochromatography detected the virus in only 11 samples (11/27; 40.7%), whereas the pwRT‐LAMP system detected the virus in 26 of the 56 samples (26/27 of the positive samples; 96.3%). These findings indicate that the mobile pwRT‐LAMP system is an accurate diagnostic system for the 2009 H1N1 influenza A virus, and has great potential utility in diagnosing future influenza pandemics. J. Med. Virol. 83:568–573, 2011. © 2011 Wiley‐Liss, Inc.

Background We developed perfluorocarbon gas-containing bubble liposomes (BL) with Arg-Gly-Asp (RGD) sequence-containing peptides, which bind to activated platelet glycoprotein IIb/IIIa complexes. The aim of this study was to examine the enhancing effects in ultrasonic thrombus imaging using these targeted BL in vitro and in vivo . Methods Liposomes composed of phosphatidylcholine and cholesterol were manufactured, and RGD peptide was attached by a covalent coupling reaction. Sonication was used to conjugate liposomes and perfluorocarbon gas, which formed targeted BL. In vitro , targeted BL were mixed with whole blood, which was allowed to coagulate while being shaken and rotated. In vivo , we administered targeted BL to 10 rabbits with acute thrombotic occlusions in the ilio-femoral artery. Thrombi were imaged using a 7.5–9MHz linear transducer and a conventional ultrasound machine, and by scanning electron microscopy. Ultrasound images were digitized, and mean pixel gray-scale level (black=0, white=255) was measured. Results In vitro , mean pixel gray-scale level of the thrombi in targeted BL group was significantly higher than in control and non-targeted BL groups (93±26 vs. 58±16, 48±9, p=0.002, n=10). Scanning electron microscopy revealed large amounts of targeted BL attached to the thrombi. In vivo , mean pixel gray-scale level of the thrombi with targeted BL was significantly higher (33.2±6.4 vs. 24.8±8.5, p=0.0051, n=10) than that before targeted BL administration. Conclusions Perfluorocarbon gas-containing BL with RGD peptide represent a novel echo contrast agent, which can markedly enhance ultrasonic thrombus imaging in vitro and in vivo , and may be useful for noninvasively diagnosing acute thrombotic vessel occlusion.

Recently, microbubbles and ultrasound have been investigated with a view to improving the transfection efficiency of nonviral delivery systems for gene by cavitation. However, microbubbles had some problems in terms of stability and targeting ability. To solve these problems, we paid attention to liposomes that had many advantages such as stable and safe in vivo and easy to modify targeting ligand. Previously, we have represented that liposomes are good drug and gene delivery carriers. In addition, we developed that the liposomes (“Bubble liposomes”) were entrapped with perfluoropropane known as ultrasound imaging gas. In this study, we assessed about feasibility of “Bubble liposomes” as gene delivery tool utilized cavitation by ultrasound irradiation. “Bubble liposomes” could effectively deliver plasmid DNA to cells by combination of ultrasound irradiation without cyototoxicity. This result suggested that “Bubble liposomes” might be a new class of tool for gene delivery.

In order to prevent secondary exposure of medical personnel to toxic materials under biochemical hazard conditions, we performed a noncontact determination of exposure to toxic conditions via 1215-MHz microwave radar and thermography. A toxic condition was induced by intravenous administration of lipopolysaccharide (LPS) in rabbits. The exposure to LPS was determined by linear discriminant analysis using non-contact derived variables.

ObjectivesWe evaluated the potential vasodilator effects of transcutaneous low-frequency ultrasound (US) in human brachial arteries.BackgroundRecent data show that transthoracic low-frequency US energy results in canine coronary artery vasodilation.MethodsBrachial artery diameters were measured before and after low-frequency US (29 kHz, 1.4 W/cm2) exposure using US imaging with a linear-array transducer. We assessed the time course of diameter changes after US in 20 subjects. In 10 of 20 subjects, brachial artery flow-mediated vasodilation (FMD) was measured to compare the effect of US to a standard method of evaluating endothelial function.ResultsSignificant vasodilation was seen after 2 min of US compared with baseline values. At 5 min of US, the brachial artery diameter increased by 4.1%. In addition, the arteries continued to dilate after US exposure. At 3 min after US there was a 5.4%, and at 5 min after US a 6.0% increase in vessel diameter (p < 0.001). These diameters returned to baseline dimensions about 20 min after stopping US. Ultrasound-mediated vasodilation and percentage FMD showed good correlation (r = 0.87; p < 0.001).ConclusionsThis is the first study to demonstrate that noninvasive transcutaneous low-frequency US energy dilates human brachial arteries. This arterial vasodilator effect has a rapid onset (within 2 min), lasts about 20 min, and is similar in magnitude to that of FMD. The vasodilator effect of US may have diagnostic and therapeutic potential in patients with or at risk for vascular disease.

The physical damage inflicted by blast waves is called primary blast injury, and lungs are vulnerable to blast waves [1]. Blast lung injuries (BLI) can be extremely critical during the super-acute phase, and hypotension is supposed to be the main cause of death (1) , but its etiology has not been elucidated. Recent studies have demonstrated that hypotension is mediated by the absence of vasoconstriction [2]. However, research investigated the effectiveness of catecholamine for BLI during the super-acute phase was not identified.