Kazuhisa Yoshiya

Early activation of γδ T lymphocytes in patients with severe systemic inflammatory response syndrome

Innate immunity plays an important role in host defense after severe insult. γδ T lymphocytes are recognized as the first line of defense against microbial invasion. In this study, we evaluated γδ T lymphocytes in the peripheral blood of patients with severe systemic inflammatory response syndrome (SIRS), and examined on role of these cells. Thirty-seven patients with severe SIRS (SIRS criteria and serum C-reactive protein ≥ 10 mg/dL) and 27 healthy volunteers were studied. Severe SIRS was caused by trauma in 14 patients (Injury Severity Score of 30.1 ± 10.8) and by sepsis in 23 patients. The counts of γδ and αβ T lymphocytes were determined by flow cytometry of cells stained with monoclonal antibodies to γδ and αβ T lymphocyte receptors. The activation of these cells was evaluated by flow cytometry of cells stained with monoclonal antibodies to CD69 and HLA-DR. Serial counts and activation of γδ and αβ T lymphocytes were also determined in eight trauma patients (Injury Severity Score of 31.0 ± 13.5) during a 2-week observation period. The count of γδ T lymphocytes in the peripheral blood of SIRS patients (30.1 ± 6.0/μL) was significantly lower (P < 0.05) than that of the healthy volunteers (104.3 ± 10.9/μL). The expression of CD69, an index of early activation of T lymphocytes, was significantly greater on γδ T lymphocytes from SIRS patients (patients 23.9% ± 3.4%, healthy controls 4.8% ± 0.6%, P < 0.05). In trauma patients, the expression of CD69 on γδ T lymphocytes increased rapidly within 48 h after injuries. In conclusion, γδ T lymphocytes are activated and decreased in the peripheral blood of severe SIRS patients. In trauma patients, the activation of γδ T lymphocytes occurs in the fairly acute phase after injuries. These results suggest a significant role for γδ T lymphocytes as early responders after severe insult.

New experimental model of Crush injury of the hindlimbs in rats

BACKGROUND Crush injury (CI) remains a life-threatening condition. Because there is a shortage of animal models of CI, we purposed to develop a reproducible model of CI of hindlimbs in rats and to evaluate correlation between the volume of muscles traumatized and the severity of CI. METHODS The right or both hindlimbs of anesthetized rats were compressed for 6 hours under blocks weighing 3 kg. This was followed by 3 hours of reperfusion. Serum lactate, base excess (BE), and potassium (K) were measured at 10 minutes after cannulaton (baseline), immediately before release (compression), and 3 hours after release (reperfusion). Serum creatine phosphokinase (CK), lactate dehydrogenase (LDH), aspartate transferase (AST) and alanine transferase (ALT) were measured at baseline and reperfusion. Muscles and kidneys were evaluated morphologically. In a separate group of animals treated in the same way, survival rate was monitored for 168 hours. RESULTS Unilateral CI did not induce serious systemic impairment. Bilateral CI resulted in severe lactic acidosis. Serum K levels increased similarly and significantly in both groups. Serum CK levels correlated strongly with the volume of muscles traumatized. Bilateral CI produced a sharp increase in serum LDH, AST and ALT levels by the end of experiment. Signs of direct cellular damage and ischemia-reperfusion injury were found in histology specimens. In bilaterally crushed rats there were patent signs of acute tubular necrosis at 24 hours after insult. All rats with unilateral CI survived, whereas mortality rate reached 58.3% in rats with bilateral CI. The majority of these animals died within 24 hours after compression. CONCLUSIONS We developed a valid experimental model of severe CI of the hindlimbs in rats. Systemic responses to CI and the severity of CI appeared to correlate strongly with the volume of muscle traumatized.

Epidemiology and outcome of adult out-of-hospital cardiac arrest of non-cardiac origin in Osaka: a population-based study

Objectives To evaluate epidemiological characteristics of out-of-hospital cardiac arrests (OHCAs) by detailed non-cardiac cause and factors associated with the outcomes after OHCAs of non-cardiac origin. Design A prospective, population-based observational study. Setting The Utstein Osaka Project. Participants 14 164 adult patients aged ≥20 years old with OHCAs due to non-cardiac origin who were resuscitated by emergency-medical-service personnel or bystanders, and then were transported to medical institutions from January 2005 to December 2011. Primary outcome measures One-month survival after OHCA. Multiple logistic regression analysis was used to assess factors that were potentially associated with the outcome. Results During the study period, the 1-month survival rate was 5.3% (755/14 164). The proportion of 1-month survival was 6.2% (510/8239) in external causes, 6.5% (94/1148) in respiratory diseases, 0.8% (11/1309) in malignant tumours, 4.9% (55/1114) in strokes and 4.1% (85/2054) in others. As for external causes, the proportion of 1-month survival was 14.3% (382/2670) in asphyxia, 4.2% (84/1999) in hanging, 0.7% (9/1300) in fall, 1.1% (12/1062) in drowning, 1.6% (12/765) in traffic injury, 3.7% (7/187) in drug overuse and 1.6% (4/256) in unclassified external causes. In a multivariate analysis, adults aged <65 years old with arrests witnessed by bystanders, with normal activities of daily living before the arrests, having ventricular fibrillation arrests, having arrests in public places, intravenous fluid levels and early Emergency Medical Service response time were significant predictors for 1-month outcome after OHCAs of non-cardiac origin. The proportion of 1-month survival of all OHCAs of non-cardiac origin did not significantly increase (from 4.3% (86/2023) in 2005 to 4.9% (105/2126) in 2011) and the adjusted OR for one-increment of year was 1.01 (95% CI 0.97 to 1.06). Conclusions From a large OHCA registry in Osaka, we demonstrated that 1-month survival after OHCAs of non-cardiac origin was poor and stable.

Profile of gene expression in the subventricular zone after traumatic brain injury.

Neural stem cells, which reside in the subventricular zone (SVZ) and dentate gyrus (DG) of adult mammals, give rise to new neurons throughout life. However, these neural stem cells do not appear to contribute to regeneration in the damaged central nervous system. Following traumatic brain injury (TBI) in adult rats, the number of proliferating cells labeled with bromodeoxyuridine (BrdU) is significantly increased in the bilateral SVZ and DG; however, these proliferating cells do not contribute to effective regeneration in the damaged area. To gain insight into the molecular mechanisms of these biological actions, changes in gene expression in the SVZ after brain trauma were examined by cDNA microarray. Of 9,596 genes screened, 97 were upregulated and 204 were downregulated. Classifying these genes according to their function suggests that TBI affects a broad range of cellular functions. The validity of the data was confirmed by RT-PCR. The expression of some genes localized in the SVZ was confirmed by in situ hybridization. This combined strategy is effective for comprehensive analysis of the pathophysiological changes in the SVZ after brain injury and should contribute to the understanding of the molecular events that occur after injury. In the future, this may enable regeneration of the damaged central nervous system.

Acute Cerebral Blood Flow Variations after Human Cardiac Arrest Assessed by Stable Xenon Enhanced Computed Tomography

In this study, changes in cerebral blood flow (CBF) during acute phase after cardiopulmonary arrest (CPA) were examined in patients using stable Xenon enhanced computed tomography (Xe-CT). All patients (8) were stabilized hemodynamically within 4 hours after admission, and Xe-CT was performed immediately after restoration of spontaneous circulation (ROSC) at 8, 24, 48, 96 and 168 hours after ROSC. The progress of patients was monitored in other hospitals and clinics after discharge. Neurological outcomes were evaluated using the Glasgow outcome scale (GOS) 6 months after admission, and scores were compared against changes in CBF. Patients were grouped by prognosis. Four patients belonged to Group A (good recovery) and Group B (2 severely disabled, 2 in persistent vegetative state). The pattern of change in CBF after ROSC was found to be significantly different between Groups A and B (p <0.05). The CBF ratio relative to normal controls was higher in Group B than Group A within 48 hours after ROSC. However, at 48, 96, and 168 hours after ROSC, the opposite was observed: The CBF ratio was significantly higher in Group A than Group B (p<0.05). Based on these results, we concluded that CBF in the patients who survived after CPA changed remarkable especially within the first week. Furthermore, patients with abnormally low CBF that returns to supernormal within the first 48 hours following CPA can be expected to recover well neurologically.

Hepatocyte growth factor in polymorphonuclear leukocytes is increased in patients with systemic inflammatory response syndrome

BACKGROUND Hepatocyte growth factor (HGF) has a significant effect on the regeneration of epithelial and endothelial cells. Studies have also shown an important role of HGF in wound healing and organ regeneration. Because recent studies indicate that polymorphonuclear leukocytes (PMNLs) store HGF in their specific granules and that HGF can be degranulated in the inflammatory tissue in which activated PMNLs migrate, we evaluated the storage and release of HGF in PMNLs from patients with systemic inflammatory response syndrome (SIRS) and attempted to examine the role of HGF from PMNLs in the systemic inflammatory process. METHODS Twenty-four patients with SIRS (serum C-reactive protein, 20.2 +/- 12.4 mg/dL [mean +/- SD]) and 18 healthy volunteers were studied. HGF in PMNLs was measured by flow cytometry by using a monoclonal antibody to HGF. The oxidative activity in PMNLs was also measured by flow cytometry. Serum HGF, interleukin (IL)-6, and IL-8 levels in each patient were measured by enzyme-linked immunosorbent assay. HGF degranulation from PMNLs was evaluated in 10 patients. RESULTS Immunocytochemistry under fluorescence microscopy revealed enhanced expression of HGF in the granules of PMNLs. HGF in PMNLs significantly increased in patients with SIRS compared with PMNLs from healthy volunteers (SIRS, 171.0 +/- 6.6 fluorescence/cell; control, 130.7 +/- 3.8 fluorescence/cell). N-formylmethionyl-leucyl-phenylalanine and lipopolysaccharide stimulation induced further increase of HGF fluorescence in PMNLs from patients. HGF degranulation from PMNLs was also significantly enhanced in patients. Moreover, oxidative activity in PMNLs was significantly enhanced in patients with SIRS. Plasma HGF (pHGF) correlated positively with IL-6 and IL-8 levels in patients (pHGF and IL-6, gamma = 0.635, p < 0.05; pHGF and IL-8, gamma = 0.827, p < 0.01), but these values did not correlate with HGF in PMNLs. CONCLUSION Activated PMNLs in SIRS patients increased HGF in their granules and demonstrate enhanced degranulation of HGF. The release of HGF from migrated PMNLs in the inflammatory tissue may play an important role in wound healing and organ regeneration under those conditions.

Induction of mRNAs and proteins for Na/K ATPase α1 and β1 subunits following hypoxia/reoxygenation in astrocytes

Characteristics of the cellular response to oxygen deprivation and subsequent reoxygenation (hypoxia/reoxygenation) include redirection of energy metabolism, increased glucose utilization and expression of oxygen-regulated proteins. Inhibition of protein synthesis during early reoxygenation period prevented effective astrocyte adaptation to hypoxia/reoxygenation, resulting in eventual cell death. To elucidate the role of astrocytes in the central nervous system in response to hypoxia/reoxygenation, we analyzed the cDNA library derived from the cultured rat astrocytes subjected to 24 h of hypoxia followed by reoxygenation by differential display, and isolated a cDNA corresponding to Na/K ATPase alpha1 subunit. The expression of Na/K ATPase alpha1 subunit mRNA as well as beta1subunit mRNA was transiently increased after reoxygenation, whereas hypoxia itself did not induce any gene expression change. Na/K ATPase alpha1 subunit protein was transiently increased, whereas the protein expression for Na/K ATPase beta1 subunit showed sustained induction after reoxygenation. Overexpression of beta1 subunit in HEK 293 cells subjected to hypoxia/reoxygenation promoted survival of the cells. These findings suggest that Na/K ATPases may contribute to maintain the cellular environment of astrocytes subjected to hypoxia/reoxygenation.

Factors associated with the difficulty in hospital acceptance at the scene by emergency medical service personnel: a population-based study in Osaka City, Japan

Objectives To investigate the association between the difficulty in hospital acceptance at the scene by emergency medical service (EMS) personnel and prehospital demographic factors and reasons for EMS calls. Design A retrospective, observational study. Setting Osaka City, Japan. Participants A total of 100 649 patients transported to medical institutions by EMS from January 2013 to December 2013. Primary outcome measurements The definition of difficulty in hospital acceptance at the scene was EMS personnel making ≥5 phone calls to medical institutions until a decision to transport was determined. Multivariable analysis was used to assess the relationship between difficulty in hospital acceptance and prehospital factors and reasons for EMS calls. Results Multivariable analysis showed the elderly, foreigners, loss of consciousness, holiday/weekend, and night-time to be positively associated with difficulty in hospital acceptance at the scene. As reasons for EMS calls, gas poisoning (adjusted OR 3.281, 95% CI 1.201 to 8.965), trauma by assault (adjusted OR 2.662, 95% CI 2.390 to 2.966), self-induced drug abuse/gas poisoning (adjusted OR 4.527, 95% CI 3.921 to 5.228) and self-induced trauma (adjusted OR 1.708, 95% CI 1.369 to 2.130) were positively associated with the difficulty in hospital acceptance at the scene. Conclusions Ambulance records in Osaka City showed that certain prehospital factors such as night-time were positively associated with difficulty in hospital acceptance at the scene, and reasons for EMS calls, such as self-induced drug abuse/gas poisoning, were also positive predictors for difficulty in hospital acceptance at the scene.

Spontaneous Occlusion of Splenic and Renal Pseudoaneurysm After Blunt Abdominal Trauma: A Case Report and Literature Review

Pseudoaneurysms caused by blunt abdominal trauma are rarely observed in solid organs. The preferred therapy for pseudoaneurysm after blunt abdominal trauma is often angiography and embolization. Here, we report a case of a spontaneous occlusion of splenic pseudoaneurysm and renal pseudoaneurysm after blunt abdominal trauma. Angiography and embolization were not required, and contrast-enhanced multi-detector computed tomography was used to monitor the patient. This case shows that spontaneous occlusion can be one of the possible outcomes of intraparenchymal splenic pseudoaneurysm and renal pseudoaneurysm after blunt abdominal trauma.

Effect of Serum Albumin Concentration on Neurological Outcome After Out-of-Hospital Cardiac Arrest (from the CRITICAL [Comprehensive Registry of Intensive Cares for OHCA Survival] Study in Osaka, Japan)

The aim of this study was to assess whether serum albumin concentration upon hospital arrival had prognostic indications on out-of-hospital cardiac arrest (OHCA). This prospective, multicenter observational study conducted in Osaka, Japan (the CRITICAL [Comprehensive Registry of Intensive Cares for OHCA Survival] study), enrolled all patients with consecutive OHCA transported to 14 participating institutions. We included adult patients aged ≥18 years with nontraumatic OHCA who achieved return of spontaneous circulation and whose serum albumin concentration was available from July 2012 to December 2014. Based on the serum albumin concentration upon hospital arrival, patients were divided into quartiles (Q1 to Q4), namely, Q1 (<2.7 g/dl), Q2 (2.7 to 3.1 g/dl), Q3 (3.1 to 3.6 g/dl), and Q4 (≥3.6 g/dl). The primary outcome was 1-month survival with favorable neurological outcome (cerebral performance category scale 1 or 2). During the study period, a total of 1,269 patients with OHCA were eligible for our analyses. The highest proportion of favorable neurological outcome was 33.5% (109 of 325) in the Q4 group, followed by 13.2% (48 of 365), 5.0% (13 of 261), and 3.5% (11 of 318) in the Q3, Q2, and Q1 groups, respectively. In the multivariable logistic regression analysis, the proportion of favorable neurological outcome in the Q4 group was significantly higher, compared with that in the Q1 group (adjusted odds ratio 8.61; 95% confidence interval 4.28 to 17.33). The adjusted proportion of favorable neurological outcome increased in a stepwise manner across increasing quartiles (p for trend <0.001). Higher serum albumin concentration was significantly and independently associated with favorable neurological outcome in a dose-dependent manner.