Risk factors for bleeding complications in patients undergoing extracorporeal cardiopulmonary resuscitation following out-of-hospital cardiac arrest: a secondary analysis of the SAVE-J II study

BACKGROUND

Bleeding is the most common complication in out-of-hospital cardiac arrest (OHCA) patients receiving extracorporeal cardiopulmonary resuscitation (ECPR). No studies comprehensively described the incidence rate, timing of onset, risk factors, and treatment of bleeding complications in OHCA patients receiving ECPR in a multicenter setting with a large database. This study aimed to analyze the risk factors of bleeding during the first day of admission and to comprehensively describe details of bleeding during hospitalization in patients with OHCA receiving ECPR in the SAVE-J II study database.

METHODS

This study was a secondary analysis of the SAVE-J II study, which is a multicenter retrospective registry study from 36 participating institutions in Japan in 2013-2018. Adult OHCA patients who received ECPR were included. The primary outcome was the risk factor of bleeding complications during the first day of admission. The secondary outcomes were the details of bleeding complications and clinical outcomes.

RESULTS

A total of 1,632 patients were included. Among these, 361 patients (22.1%) had bleeding complications during hospital stay, which most commonly occurred in cannulation sites (14.3%), followed by bleeding in the retroperitoneum (2.8%), gastrointestinal tract (2.2%), upper airway (1.2%), and mediastinum (1.1%). These bleeding complications developed within two days of admission, and 21.9% of patients required interventional radiology (IVR) or/and surgical interventions for hemostasis. The survival rate at discharge of the bleeding group was 27.4%, and the rate of favorable neurological outcome at discharge was 14.1%. Multivariable logistic regression analysis showed that the platelet count (< 10 × 104/μL vs > 10 × 104/μL) was significantly associated with bleeding complications during the first day of admission (adjusted odds ratio [OR]: 1.865 [1.252-2.777], p = 0.002).

CONCLUSIONS

In a large ECPR registry database in Japan, up to 22.1% of patients experienced bleeding complications requiring blood transfusion, IVR, or surgical intervention for hemostasis. The initial platelet count was a significant risk factor of early bleeding complications. It is necessary to lower the occurrence of bleeding complications from ECPR, and this study provided an additional standard value for future studies to improve its safety.

Long-term psychiatric disorders in families of severe COVID-19 patients

Aim

The present study aimed to describe in detail the changes to and assess the risk factors for poor long-term outcomes of psychiatric disorders in families of COVID-19 patients.

Methods

A single-center, retrospective study using questionnaires. Family members of patients admitted to the intensive care unit (ICU) with severe COVID-19 participated. Psychiatric disorders refer to the psychological distress such as anxiety, depression, and posttraumatic stress disorder (PTSD) experienced by the patient's family.

Results

Forty-six family members completed the survey and were analyzed. Anxiety, depression, and PTSD occurred in 24%, 33%, and 2% of family members, respectively, and psychiatric disorders occurred in 39%. On multivariable analysis, living in the same house with the patient was independently associated with a lower risk of psychiatric disorders in families of COVID-19 patients (OR, 0.180; 95% CI, 0.036-0.908; p = 0.038). Furthermore, four family members overcame psychiatric disorders, and six family members newly developed psychiatric disorders during the one-year follow-up period.

Conclusion

Approximately 40% of family members had long-term psychiatric disorders, and some of them overcame the psychiatric disorders, and some newly developed psychiatric disorders over the one-year follow-up. Living in the same house with the patient was possibly significantly associated with the reduction of long-term symptoms of psychiatric disorders, but this result must be interpreted with care. Further large studies are needed to examine the factors associated with the long-term mental status of family members.

Frequency, clinical characteristics, and outcomes of pneumonia in patients with out-of-hospital cardiac arrest undergoing extracorporeal cardiopulmonary resuscitation

Aim

This study aimed to describe the frequency, clinical characteristics, and outcomes of pneumonia in OHCA patients treated with ECPR in a multicenter setting.

Methods

This is a secondary analysis of the SAVE-J II study, which was a multicenter, retrospective cohort of OHCA patients treated with ECPR. Age, sex, comorbidities, presence of witnessed CA, presence of bystander CPR, initial rhythm, cause of CA, low-flow time, initiation of targeted temperature management, details of sputum culture, pneumonia, and prophylactic antibiotic use were recorded. Pneumonia was diagnosed when the patients met all the clinical, radiologic, and microbiologic criteria acquired after hospitalization.

Results

In total, 1,986 patients were included in the analysis, and 947 (48%) died during the first 2 days of admission. A prophylactic antibiotic was used in 712 (35.9%) patients. Overall, the hazard of death was high on days 1 and 2 of admission, exceeding 20% on both days; 251 (12.6%) patients developed pneumonia during hospitalization, and the hazard of pneumonia development remained high (>2%) in the first 7 days of admission.Staphylococcus aureus and Klebsiella species were commonly identified in the sputum culture. Among patients who survived the first 7 days, the odds ratio (OR) of those with pneumonia and unfavorable neurological outcomes defined by cerebral performance category 3-5 was approximately 1. In those who survived the first 10 days, the OR was greater than 1 with a wide confidence interval.

Conclusions

This is the first study describing details of pneumonia in OHCA patients treated with ECPR using a large dataset.

A Case of Sudden Cardiac Arrest After Brainstem Infarction

Research on the causes of sudden cardiac arrest (CA) after ischemic stroke, especially disruption of the autonomic nervous system's central control, has recently focused more on the widespread cortical and subcortical network than on autonomic circuits at the spinal and brainstem level. However, no clinical case of sudden CA requiring cardiopulmonary resuscitation (CPR) after brainstem infarction has been reported. We report a case of a 78-year-old woman who died suddenly from a brainstem infarction. Her husband heard a falling sound and found her unresponsive and lying with agonal breathing. The initial cardiac rhythm was pulseless electrical activity confirmed by emergency medical technicians. Recovery of spontaneous circulation was achieved after CPR. Basilar artery occlusion was shown on computed tomography, but no other findings that could have caused CA were found. Targeted temperature management was initiated, but she died on hospital day 22. Brainstem infarction may cause sudden CA; therefore, definitive treatment may achieve better outcomes.

Clinical characteristics and outcomes after extracorporeal cardiopulmonary resuscitation in out-of-hospital cardiac arrest patients with an initial asystole rhythm

AIM

This study aimed to describe the characteristics of cases of out-of-hospital cardiac arrest (OHCA) with an initial asystole rhythm in which extracorporeal cardiopulmonary resuscitation (ECPR) was introduced and discuss the clinical indications for ECPR in such patients.

METHODS

This was a secondary analysis of the SAVE-J II study, a retrospective, multicentre, registry study involving 36 participating institutions in Japan. Patients with an initial asystole rhythm were selected. Favourable neurological outcomes (cerebral performance categories 1-2) constituted the primary outcome.

RESULTS

In total, 202 patients met the inclusion criteria, with favourable neurological outcomes at hospital discharge in 12 patients (5.9%). Causes of cardiac arrest with favourable neurological outcomes were hypothermia (7 cases), acute coronary syndrome (2 cases), arrhythmia (2 cases), and pulmonary embolism (1 case). Among patients with non-hypothermia (temperature ≥32 °C) on hospital arrival with the cardiac rhythm of asystole or pulseless electrical activity (PEA) on arrival, all 107 patients (66 asystole, 41 PEA) who lacked one or more of the requirements (witness; bystander CPR; signs of life or pupil < 5 mm) had unfavourable neurological outcomes. All 5 cases with favourable neurological outcomes, except for 1 case with a short duration of no-flow time that was highly suspected based on the patient's history, met all the requirements on hospital arrival.

CONCLUSIONS

A total of 202 ECPR cases with an initial asystole rhythm, including 12 patients with favourable neurological outcomes, were described. Even if the initial cardiac rhythm is asystole, ECPR could be considered if certain conditions are met.

Outcome of extracorporeal membrane oxygenation use in severe accidental hypothermia with cardiac arrest and circulatory instability: A multicentre, prospective, observational study in Japan (ICE-CRASH study)

AIM

To elucidate the effectiveness of extracorporeal membrane oxygenation (ECMO) in accidental hypothermia (AH) patients with and without cardiac arrest (CA), including details of complications.

METHODS

This study was a multicentre, prospective, observational study of AH in Japan. All adult (aged ≥18 years) AH patients with body temperature ≤32 °C who presented to the emergency department between December 2019 and March 2022 were included. Among the patients, those with CA or circulatory instability, defined as severe AH, were selected and divided into the ECMO and non-ECMO groups. We compared 28-day survival and favourable neurological outcomes at discharge between the ECMO and non-ECMO groups by adjusting for the patients' background characteristics using multivariable logistic regression analysis.

RESULTS

Among the 499 patients in this study, 242 patients with severe AH were included in the analysis: 41 in the ECMO group and 201 in the non-ECMO group. Multivariable analysis showed that the ECMO group was significantly associated with better 28-day survival and favourable neurological outcomes at discharge in patients with CA compared to the non-ECMO group (odds ratio [OR] 0.17, 95% confidence interval [CI]: 0.05-0.58, and OR 0.22, 95%CI: 0.06-0.81). However, in patients without CA, ECMO not only did not improve 28-day survival and neurological outcomes, but also decreased the number of event-free days (ICU-, ventilator-, and catecholamine administration-free days) and increased the frequency of bleeding complications.

CONCLUSIONS

ECMO improved survival and neurological outcomes in AH patients with CA, but not in AH patients without CA.

Persistent Air Embolism after Blunt Chest Trauma with Recovery to Pre-Existing Consciousness Level: A Case Report and Literature Review

We report the case of a 71-year-old woman in whom cerebral air embolism resulted from blunt chest trauma. The woman had been lying on her left side for a while after the injury, and air traveled to the right side of the brain. As a result, a cerebral infarction occurred in the right cerebral hemisphere that caused loss of consciousness for more than 40 days. The patient recovered consciousness eventually; thus, it is important to monitor the improvement in a patient's state of consciousness, with repeated multi-modality imaging evaluations over a long period.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020)

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created as revised from J-SSCG 2016 jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in September 2020 and published in February 2021. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. The purpose of this guideline is to assist medical staff in making appropriate decisions to improve the prognosis of patients undergoing treatment for sepsis and septic shock. We aimed to provide high-quality guidelines that are easy to use and understand for specialists, general clinicians, and multidisciplinary medical professionals. J-SSCG 2016 took up new subjects that were not present in SSCG 2016 (e.g., ICU-acquired weakness [ICU-AW], post-intensive care syndrome [PICS], and body temperature management). The J-SSCG 2020 covered a total of 22 areas with four additional new areas (patient- and family-centered care, sepsis treatment system, neuro-intensive treatment, and stress ulcers). A total of 118 important clinical issues (clinical questions, CQs) were extracted regardless of the presence or absence of evidence. These CQs also include those that have been given particular focus within Japan. This is a large-scale guideline covering multiple fields; thus, in addition to the 25 committee members, we had the participation and support of a total of 226 members who are professionals (physicians, nurses, physiotherapists, clinical engineers, and pharmacists) and medical workers with a history of sepsis or critical illness. The GRADE method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members.As a result, 79 GRADE-based recommendations, 5 Good Practice Statements (GPS), 18 expert consensuses, 27 answers to background questions (BQs), and summaries of definitions and diagnosis of sepsis were created as responses to 118 CQs. We also incorporated visual information for each CQ according to the time course of treatment, and we will also distribute this as an app. The J-SSCG 2020 is expected to be widely used as a useful bedside guideline in the field of sepsis treatment both in Japan and overseas involving multiple disciplines.

Clinical characteristics and outcomes of critically ill COVID-19 patients in Tokyo: a single-center observational study from the first wave

Background

Many studies have been published about critically ill coronavirus disease 2019 (COVID-19) during the early phases of the pandemic but the characteristic or survival of critically ill Japanese patients have not yet been investigated. We sought to investigate the characteristics, inflammatory laboratory finding trends, and outcomes among critically ill Japanese patients who were admitted to the intensive care unit (ICU) with the first wave of COVID-19.

Methods

A retrospective observational study was performed in a single institution in the center of Tokyo. Laboratory-confirmed COVID-19 patients admitted to the ICU from March 19 to April 30, 2020 were included. Trends for significant inflammatory laboratory findings were analyzed. In-hospital death, days of mechanical ventilation or oxygen supplementation, days of ICU or hospital stay were followed until May 26, 2020.

Results

Twenty-four patients were included. Median age was 57.5 years, and 79% were male. The neutrophil-to-lymphocyte ratio was elevated to a median of 10.1 on admission and peaked on Day 10 of illness. Seventeen patients were intubated on Day 11 of illness and received mechanical ventilation. One patient underwent extracorporeal membrane oxygenation. The majority (88%) received systemic steroids, including 16 patients who received high dose methylprednisolone (500–1000 mg). Favipiravir was used in 38% of patients. Two patients, including 1 who refused intensive care, died. Eighteen patients were discharged. Median length of ICU and hospital stay for all patients was 6 and 22 days, respectively. Median length of ventilator dependency was 7 days. Four patients underwent a tracheostomy and received prolonged ventilation for more than 21 days. One patient receiving mechanical ventilation died. All survivors discontinued ventilator use.

Conclusions

Mortality was remarkably low in our single institutional study. Three survivors received mechanical ventilation for more than 3 weeks. Trends of clinically significant laboratory markers reflected the clinical course of COVID-19.

Empyema with fistula successfully treated with a comprehensive approach including bronchial blocker and embolization receiving veno-venous extracorporeal membrane oxygenation

Background

Complicated empyema accompanied by bronchopleural fistula (BPF) has high mortality. The treatment strategy for severe respiratory failure due to empyema with BPF has yet to be established.

Case Presentation

A 70-year-old man was brought to our hospital and diagnosed with right empyema, BPF (at bronchi B4-10), and secondary left pneumonia. We initiated drainage followed by veno-venous extracorporeal membrane oxygenation due to the severe hypoxia. First, the patient underwent endoscopic treatment with obstructive materials (known as endobronchial Watanabe spigot [EWS]) at B8-10, and was weaned off veno-venous extracorporeal membrane oxygenation on day 7. A secondary EWS was carried out at B4-6. A combination of medical treatments (drainage, antibiotics, nutritional therapy, and rehabilitation) improved his general condition. The patient was able to leave the hospital on foot.

Conclusion

A comprehensive approach could explain the success of the medical treatment. The principal components are the repeated application of EWS as damage control.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020)

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created as revised from J-SSCG 2016 jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in September 2020 and published in February 2021. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. The purpose of this guideline is to assist medical staff in making appropriate decisions to improve the prognosis of patients undergoing treatment for sepsis and septic shock. We aimed to provide high-quality guidelines that are easy to use and understand for specialists, general clinicians, and multidisciplinary medical professionals. J-SSCG 2016 took up new subjects that were not present in SSCG 2016 (e.g., ICU-acquired weakness [ICU-AW], post-intensive care syndrome [PICS], and body temperature management). The J-SSCG 2020 covered a total of 22 areas with four additional new areas (patient- and family-centered care, sepsis treatment system, neuro-intensive treatment, and stress ulcers). A total of 118 important clinical issues (clinical questions, CQs) were extracted regardless of the presence or absence of evidence. These CQs also include those that have been given particular focus within Japan. This is a large-scale guideline covering multiple fields; thus, in addition to the 25 committee members, we had the participation and support of a total of 226 members who are professionals (physicians, nurses, physiotherapists, clinical engineers, and pharmacists) and medical workers with a history of sepsis or critical illness. The GRADE method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members. As a result, 79 GRADE-based recommendations, 5 Good Practice Statements (GPS), 18 expert consensuses, 27 answers to background questions (BQs), and summaries of definitions and diagnosis of sepsis were created as responses to 118 CQs. We also incorporated visual information for each CQ according to the time course of treatment, and we will also distribute this as an app. The J-SSCG 2020 is expected to be widely used as a useful bedside guideline in the field of sepsis treatment both in Japan and overseas involving multiple disciplines.

Development of acute kidney injury with massive granular casts and microscopic hematuria in patients with COVID-19: two case presentations with literature review

BACKGROUND

Complications of acute kidney injury (AKI) are common in patients with coronavirus disease in 2019 (COVID-19). However, clinical characteristics of COVID-19-associated AKI are poorly described. We present two cases of severe COVID-19 patients with AKI.

CASE PRESENTATION

A 77-year-old woman was suspected of having vancomycin-associated AKI, and a 45-year-old man was suspected of having heme pigment-induced AKI caused by rhabdomyolysis. The granular cast, which is known to be a valuable diagnostic tool for confirming the diagnosis of acute tubular necrosis, was detected in both patients at the onset of AKI. Interestingly, both patients also developed microscopic hematuria at the occurrence of AKI, and one patient had elevated d-dimer and low platelet levels simultaneously.

CONCLUSIONS

Some reports suggested that COVID-19-associated microangiopathy contributed to the kidney damage. Therefore, it is possible that our patients might have accompanied renal microangiopathy, and that this pathological background may have caused exaggerated tubular damage by vancomycin or heme pigment. The etiology of AKI in patients with COVID-19 is multifactorial. Superimposition of nephrotoxin(s) and virus-associate intra-renal microangiopathy may be a crucial trigger of kidney injury leading to severe AKI in COVID-19 patients. Therefore, in COVID-19 patients, risk factors for AKI should be taken into consideration to prevent its progression into severe AKI.

Neuroleptic malignant syndrome in patients with COVID-19

We report the first two cases of Coronavirus Disease 2019 (COVID-19) who were receiving intensive care including favipiravir, and were clinically diagnosed with neuroleptic malignant syndrome (NMS) to focus attention on NMS in COVID-19 management. Case 1: A 46-year-old-man with acute respiratory distress syndrome (ARDS) caused by COVID-19 infection was being administered favipiravir. Fentanyl, propofol, and rocuronium were also given. On day 3, midazolam administration was initiated for deep sedation. On day 5, his high body temperature increased to 41.2 °C, creatine kinase level elevated, and he developed tachycardia, tachypnea, altered consciousness, and diaphoresis. NMS was suspected, and supportive therapy was initiated. High-grade fever persisted for 4 days and subsided on day 9. Case 2: A 44-year-old-man with ARDS caused by COVID-19 infection was being treated with favipiravir. On day 5, risperidone was started for delirium. On day 7, his body temperature suddenly increased to 40.8 °C, his CK level elevated, and he developed tachycardia, tachypnea, altered consciousness, and diaphoresis. NMS diagnosis was confirmed, and both, favipiravir and risperidone were discontinued on day 8. On the same day, his CK levels decreased, and his body temperature normalized on day 9. Patients with COVID-19 infection frequently require deep sedation and develop delirium; therefore, more attention should be paid to the development of NMS in patients who are being administered such causative agents. The mechanism underlying the occurrence of NMS in COVID-19 patients treated with favipiravir remains unknown. Therefore, careful consideration of NMS development is necessary in the management of COVID-19 patients.

Association between inflammation in acute phase and early onset pneumonia in patients with out-of-hospital cardiac arrest treated with extracorporeal cardiopulmonary resuscitation

BACKGROUND

Early onset pneumonia (EOP) in patients with cardiac arrest treated with targeted temperature management is a recently debated issue. We assessed the association between C-reactive protein (CRP) levels and development of EOP in patients treated with extracorporeal cardiopulmonary resuscitation (ECPR).

METHODS AND RESULTS

We reviewed the data of all patients admitted to our hospital after out-of-hospital cardiac arrest treated with ECPR between April 2006 and April 2019 who survived for at least 48 h. We collected demographic data, cardiac arrest characteristics, prophylactic antibiotic use, and neurologic outcomes. Diagnosis of EOP was made based on clinical, radiological, and microbiological criteria. The primary endpoint was the association between the incidence of EOP and CRP levels from day 1 to day 4. A total of 55 patients were included, of which 20 developed EOP. CRP levels on days 3 and 4 were significantly elevated in patients who developed EOP (13.1 [11.8-21.1] mg/dL versus 11.6 [7.4-15.2] mg/dL, P = 0.005; and 19.0 [16.9-27.1] mg/dL versus 14.7 [7.4-21.2] mg/dL, P = 0.019, respectively). In the multivariable logistic regression model, the CRP level on day 3 was significantly associated with the development of EOP (odds ratio 1.22; 95% confidence interval 1.06-1.41; P = 0.001).

CONCLUSIONS

Increased inflammation in acute phase was associated with development of EOP in patients treated with ECPR.

Pneumonia and Extracorporeal Cardiopulmonary Resuscitation Followed by Targeted Temperature Management in Patients With Out-of-Hospital Cardiac Arrest - Retrospective Cohort Study

Background: We examined the association between initiation of extracorporeal cardiopulmonary resuscitation (ECPR) and the incidence of infectious complications, such as pneumonia, sepsis, and bacteremia, after out-of-hospital cardiac arrest (OHCA) in patients who received targeted temperature management (TTM). Methods and Results: This retrospective study used data from hospital medical records of patients with OHCA treated with TTM who had been admitted to St. Luke's International Hospital between April 2006 and December 2018. The primary endpoint was the association between the type of CPR and the incidence of early onset pneumonia in the intensive care unit (ICU; between 48 h and 7 days of hospitalization). Univariate and multivariate logistic regression analyses were performed for the primary endpoints. After applying the inclusion/exclusion criteria, 254 patients were included in the analyses; of these, 52 were enrolled in the ECPR group, and 202 were enrolled in the CCPR group. Median age was 58 years, 88.5% were male, prophylactic antibiotics were used in 80.3%, and favorable neurological outcomes were observed in 51.9%. On multivariate analysis, ECPR (odds ratio [OR], 2.78; 95% CI: 1.16-6.66; P=0.037) was significantly associated with the development of early onset pneumonia. Conclusions: ECPR was an independent predictor of pneumonia after OHCA in patients who received TTM.

Clinical and radiological features in four adolescents with nutcracker syndrome

We describe four adolescents with the nutcracker syndrome. In three patients, the nutcracker syndrome was detected through mass urinary screening; the other patient was diagnosed after a sudden onset of dark urine. All patients underwent magnetic resonance angiography (MRA) for diagnosis of the nutcracker syndrome, which revealed dilatation of the left renal vein ranging between 7.4 and 13 mm at the hilar portion. A renal biopsy, performed in three patients, showed no remarkable abnormalities in the glomerulus or tubulointerstitial tissue. The patients complained of physical discomfort, including headache, abdominal pain, fainting, and tachycardia mimicking clinical symptoms of an orthostatic disturbance. However, no chronic systemic diseases were detected in any of the patients after repeated laboratory examinations. An orthostatic disturbance preceded diagnosis in three patients. This report indicates that the nutcracker syndrome may cause serious physical ailments that clinically mimic an orthostatic disturbance. It may be important to identify the nutcracker syndrome among children who manifest non-specific physical complaints. MRA could be a safe and reliable method for diagnosing the nutcracker syndrome.

Overexpression of bcl-2 in transient abnormal myelopoiesis associated with Down syndrome

Transient abnormal myelopoiesis (TAM) is a haematological complication found in Down syndrome. To determine the mechanisms of sustained proliferation of TAM cells, we studied the expression of apoptosis-related proteins, such as bcl-2, Fas (APO-1/CD95) and p-53, in peripheral blood cells from a new-born infant with Down syndrome and TAM. Using flow cytometry, peripheral blood mononuclear cells (PBMCs), consisting mostly of blast cells, showed marked expression of bcl-2 protein but not of Fas or p-53 products. DNA gel electrophoresis of PBMCs, cultured in the absence of serum factors, revealed no marked fragmentation. Our findings suggest that bcl-2 overexpression may be associated with prolonged cell survival of TAM cells.

[Evaluation of thrombomodulin and tumor necrosis factor-alpha levels in patients with hemolytic uremic syndrome caused by enterohemorrhagic Escherichia coli O157:H7 infection]

To investigate the role of thrombomodulin (TM) and tumor necrosis factor-alpha (TNF-alpha) in hemolytic uremic syndrome (HUS), serum and urinary levels of TM and TNF-alpha were determined in patients with hemorrhagic enterocolitis (HC) of enterohemorrhagic E. coli O157:H7 infection. These patients were divided into two groups: an HUS group consisting of patients with HUS; an HC group consisting of patients without HUS. In the 10 days after the onset of diarrhea, the serum TM and TNF-alpha levels in the HUS group were significantly elevated compared with those in the control group but decreased after 11 days. The serum TM and TNF-alpha levels in the HC group were not elevated compared with those in the control group except for one case of TNF-alpha. It is suggested that the serum TM elevation showed the severity of endothelial cell damage. Urinary TM and TNF-alpha levels in the HUS group were significantly elevated in the first 10 days. The urinary TNF-alpha levels rapidly decreased after 11 days, while the urinary TM levels were persistently high. From these results, the sustained elevation of the urinary TM levels suggested the persistent presence of renal endothelial cell damage, and the decrement of urinary TNF-alpha levels suggested that TNF-alpha acted as a trigger of the renal endothelial cell damage in the first 10 days.

[Influence for cultured renal cell growth ability by toxins of Escherichia coli]

There have been many reports indicating that Escherichia coli from pyelonephritis may exhibit several specific phenotypes. The purpose of the present study was to examine the effects of various toxins from Escherichia coli on cultured renal cell growth. alpha-hemolysin suppressed growth of Mardin Darby canine kidney (MDCK) cells in a dose-dependent manner. A low dose of O-antigen suppressed MDCK cell growth, while a high dose of the antigen increased the cell growth slightly. K:1-antigen had no effect on MDCK cell growth. Mesangial cell growth was not affected by alpha-hemolysin. A significant increase in mesangial cell growth was recognized by the O- or K:1-antigen. From these results it can be speculated that alpha-hemolysin from Escherichia coli may play a leading role, and O- or K-antigen may play a supporting role in the pathogenesis of pyelonephritis.

A nitric oxide-sensitive electrode: requirement of lower oxygen concentration for detecting nitric oxide from the tissue

In order to directly detect nitric oxide (NO) liberated from isolated tissue, a practical and convenient method using a nitric oxide-sensitive electrode is described. To avoid the nonselective signal caused by ionic substances, the electrode was covered with three layers but remains permeable for gaseous substances. In a solution bubbled with 20% oxygen (pO2, approximately 150 mm Hg), administration of S-nitroso-N-acetyl-d, l-penicillamine (SNAP) at concentrations greater than 10(-7) mol/L elicited an electrode response. Based on a comparison with the chemical determination of NO released from SNAP, the electrode may be able to detect nitric oxide around nmol/L. At least 30 nmol NO per liter in anoxic conditions was reported to be detected by this electrode (Matsui, 1995). In a specially designed small chamber, the electrode was attached on the surface of endothelial side of the isolated aorta of the guinea pig. When carbachol was added to the chamber, the electrode responded when the solution was bubbled with 20% but not with 40% or 95% of oxygen, suggesting a much faster decomposition of nitric oxide in the presence of higher concentrations of oxygen. The electrode response to carbachol was abolished in the presence of NG-monomethyl-L-arginine or nitro arginine. These results suggest that the electrode method described in this manuscript is suitable for detecting nitric oxide liberated from isolated tissues when comparatively low oxygen levels are present in the physiological salt solution.

[A case of Bufferin induced acute interstitial nephritis--analysis of immune cells and cytokine]

This paper describes a case report of acute interstitial nephritis associated with Bufferin. A 15-year-old girl were referred to our hospital due to fever and renal dysfunction. Laboratory findings showed elevation of serum BUN and creatinine, and increased urinary beta 2-MG excreation. Light microscopic findings of her renal biopsy specimen revealed edema and numerous inflammatory cells in the interstitium, and minor alterations in glomeruli. The interstitial infiltrates consisted mainly of T cells and also monocytes/macrophages. Interstitial cells were labelled with antibodies to interleukin (IL)-1 and tumor necrose factor (TNF). Bufferin was positive by lymphocyte stimulation test. Thus, we considered that this drug was causative in this case. This observation suggests the participation of cell-mediated immune injury in drug induced acute interstitial nephritis.

Tertiary peptide bond containing-oligo(Leu)s. Conformational studies in solution of oligo (L-leucine)s with L-proline residue and glycyl-N-(2, 4-dimethoxybenzyl)-L-leucine sequence

In order to elucidate the role of tertiary peptide bonds in the conformational development and solubility improvement of peptides, the conformational properties of oligo(Leu)s with the Pro residue and the Gly-(Dmob)Leu sequence were investigated in solution using i.r. absorption, CD, and molar rotation measurements. The i.r. absorption spectroscopy indicated that the peptides soluble in inert solvents such as CCl4 and toluene had a predominantly beta-sheet structure in these solvents. The conformations of the peptides in CCl4 and toluene were essentially the same as those in a solid state, whereas in THF and in MeOH, the peptides examined were efficiently subjected to solvation, and a randomly coiled structure was predominant. In order to confirm the randomly coiled structure, measurements have been made of the molar rotations of the peptides in a variety of strong proton acceptor and donor solvents. CD measurements are also carried out in MeOH. Through the investigations, it was shown that the protection of peptide bonds and the insertion of the Pro residue had the same effect on conformational and solubilizing behaviors and induced onset of an unordered structure and easy solvation of the peptides in medium and high polarity-solvents.

Scanning electron microscope study of dentin exposed by contact facets and cervical abrasion

Scanning electron microscope studies of exposed dentin revealed superficial surface accumulations and intratubular changes.