Ozone production by amino acids contributes to killing of bacteria

Reactive oxygen species produced by phagocytosing neutrophils are essential for innate host defense against invading microbes. Previous observations revealed that antibody-catalyzed ozone formation by human neutrophils contributed to the killing of bacteria. In this study, we discovered that 4 amino acids themselves were able to catalyze the production of an oxidant with the chemical signature of ozone from singlet oxygen in the water-oxidation pathway, at comparable level to antibodies. The resultant oxidant with the chemical signature of ozone exhibited significant bactericidal activity in our distinct cell-free system and in human neutrophils. The results also suggest that an oxidant with the chemical signature of ozone produced by neutrophils might potentiate a host defense system, when the host is challenged by high doses of infectious agents. Our findings provide biological insights into the killing of bacteria by neutrophils.     

Mortality risk attributable to atrial fibrillation in middle-aged and elderly people in the Japanese general population: nineteen-year follow-up in NIPPON DATA80.

BACKGROUND: The extent to which atrial fibrillation (AF) contributes to mortality in the Japanese general population has not been clarified. METHODS AND RESULTS: A randomly sampled general population from all over Japan (4,154 men, 5,329 women; age > or =30 years) was enrolled. Single electrocardiogram recordings were taken in the baseline survey. Stroke death, cardiovascular deaths and all-cause deaths during the subsequent 19 years were analyzed by the presence of AF at baseline. Cox's regression analysis was carried out to estimate the hazard ratios (HRs) of each cause of death attributable to AF after adjusting for other risk factors. Prevalence of AF was 0.64% in the study. The observed person-years were 162,980 among persons without AF and 699 among persons with AF. There were 1,919 deaths. Multivariate adjusted HRs for stroke death, cardiovascular death and all-cause death were 2.69, 2.76 and 1.88, respectively (p<0.05). These HRs were 14.7, 9.63 and 4.00 among persons aged 64 years or younger (p<0.05). CONCLUSION: AF affects stroke mortality, cardiovascular mortality and all-cause mortality in the Japanese general population. Careful attention should be paid to persons with AF in order to prevent future cardiovascular events.     

Influence of mild-to-moderate alcohol consumption on cardiovascular diseases in men from the general population

Background and methodsThere is controversy about the association between mild-to-moderate alcohol consumption and a reduced risk of cardiovascular diseases. The relationships between daily alcohol consumption and the incidence of acute myocardial infarction (MI) or ischemic stroke (IS) were examined in men in a community-based, prospective cohort study (n = 8014, age 40–80 years, mean age = 64.1 years). Alcohol consumption was categorized into 3 groups (A1, none or occasional; A2, ≤25 g/day; A3, >25 g/day as ethanol) at baseline.ResultsDuring the mean follow-up of 5.5 years, 53 MIs and 186 ISs occurred. On Cox regression analysis adjusted for age, hypertension, diabetes, dyslipidemia, smoking index, and body mass index (BMI), the hazard ratio (HR) for incident MI was significantly lower in the A2 group than in the A1 group (HR = 0.49, p = 0.043). The HR for incident MI in the A3 group tended to be lower than in the A1 group (HR = 0.53, p = 0.10). In obese subjects, while a significantly lower HR for incident MI in the A2 group was retained (HR = 0.29, p = 0.049), no significant difference in the HR of the A3 group compared with the A1 group was found. No significant differences were found in the IS-free curve among the 3 groups of alcohol consumption.ConclusionsAlcohol consumption may have a protective effect on the onset of MI but not on IS in the general population. A U-shaped relation between alcohol consumption and incident MI was found in obese subjects. An appropriate limit for daily alcohol consumption, depending on the risk of ischemic heart disease, may need to be established.     

Z‐axis video for cytology database is a useful tool for the case presentation prior to the cytology training workshop

We have built a database on the Internet managing z‐axis video for cytology (Zavic), and report on a new style of case discussion supported by the Zavic database. Z‐axis video for cytology is a movie file derived from the video recording of a microscopic field with changes in the focus. We used it for the case presentation of EUS‐FNA of pancreatic lesions on the Internet prior to a training workshop. The attendees were asked to observe the Zavic and to make diagnoses of 20 cases before the workshop. Fourteen attendees also observed lesions under a microscope on that day, and the results were compared with those of Zavic observation. The evaluation of the Zavic database (DB) was surveyed by a questionnaire. The average number of accurate diagnoses by 46 Zavic observers was 10.8. These accuracies for those who observed both the Zavic and glass slides were 11.57 and 11.43, respectively, for the videos and slides. Compared with Zavic observation alone, the diagnoses with glass slide observation were shifted to a correct diagnosis in two cases, but were shifted to an incorrect diagnosis in two cases. Approximately 60% of Zavic observers replied in the questionnaire that the movies on Zavic DB started to play within 3–4 seconds after clicking the play button. We successfully carried out the new style of case discussion supported by the Zavic DB. It was evaluated favorably by many attendees, who were psychologically still dependent on the glass slide observation. Diagn. Cytopathol. 2013. © 2011 Wiley Periodicals, Inc.     

Comparison of plasma active glucagon-like peptide-1 (GLP-1) levels assayed with or without plasma extraction in non-diabetic men

Recently, interference from cross-reacting peptides in plasma has been recognized as being responsible for inter-subject differences in active glucagon-like peptide-1 (GLP-1) values. An ethanol or solid-phase extraction step could reduce such interference. A working group of the Japan Diabetes Society now recommends the inclusion of an extraction step when measuring active GLP-1 values. We measured the active GLP-1 levels of 200 specimens derived from 10 subjects using both methods and compared the results. The active GLP-1 levels measured by extraction method for 169 specimens with values greater than 2.0 pM tended to be lower than those by direct method. However, the correlation between the GLP-1 levels measured by extraction and direct method was r=0.9225 (p < 0.0001). In one case, the active GLP-1 level obtained using the extraction method was significantly lower than that obtained using the direct method. Therefore, though there is a good correlation between the two methods, extraction is recommended for more accurate active GLP-1 measurements.     

Plasma B-type natriuretic peptide is useful for cardiovascular risk assessment in community-based diabetes subjects: comparison with albuminuria

Diabetes mellitus (DM) is a strong risk factor for cardiovascular (CV) disease. Plasma B-type natriuretic peptide (BNP) levels are elevated in various types of cardiac diseases. Increased plasma BNP levels have been reported to be associated with CV risk in apparently healthy individuals. However, no studies have yet examined the specific value of plasma BNP for predicting CV incidence in unselected DM subjects in a community-based population.In a community-based DM cohort (n = 1,059, mean = 66 years), baseline BNP levels were determined, and CV events were followed and captured prospectively. The cohort was divided by plasma BNP quintiles. The Cox proportional hazard model was used to determine the relative hazard ratios (HR) among the quintiles. In addition, the effects of adding the plasma BNP or urine albumin-to-creatinine ratio (UACR) to an established CV risk scoring model was examined by calculating the area under the receiver operating characteristic (ROC) curve (AUC).During the 5.7 year follow-up period, CV events were identified in 65 of the DM cohort. There was a significant association between plasma BNP levels and CV event rate (P < 0.001). HR was significantly increased in the highest quintile compared to the lowest (HR = 4.38; 95%CI 1.69 -11.84). The AUC generated from ROC analysis of the Framingham risk score for predicting general CV events was improved by adding BNP testing (from 0.66 to 0.74; P = 0.05), but not by adding UACR (from 0.66 to 0.67; P = 0.49).In a community sample of people with DM, plasma BNP levels above the 80 percentile are directly associated with CV risk, and measurement of plasma BNP alone or in conjunction with an established CV risk score is of value in predicting CV events in these subjects.     

The effect of different positions on lower limbs skin perfusion pressure

We have encountered situations of patients with critical limb ischemia accompanied by pain at rest and necrosis, who hang their legs down from the bed during sleep. This lower limb position is known to be a natural position, which reduces pain in the lower extremity induced by ischemia. However, the effect of this position on blood flow of the lower extremity is poorly understood. We studied whether measurements of skin perfusion pressure (SPP) changes by leg position and the difference between healthy adults and patients with critical limb ischemia. The subjects of this study were 10 healthy adults and 11 patients with critical limb ischemia. Patients with critical limb ischemia, including both dorsum of foot and plantar of foot, having SPP of lower limbs of less than 40 mmHg (supine position) were the object of this study. SPP was measured on four positions (supine position, lower limbs elevation position, sitting position, and reclining bed elevation of 20^° position). In sitting position, both the number of healthy adults and critical patients show significant increases in SPP compared with the other three positions. These results suggest that sitting position is effective to keep good blood stream of lower limbs not only in healthy adults but also in patients with critical limb ischemia. However, an appropriate leg position should not have lower limbs hang downwards for long periods time because edema is caused by the fall in venous return in lower limbs, and the wound healing is prolonged.Our clinical research could be more useful in the future, particularly in developing countries, for surgeons managing wounds in leg and foot and preserving ischemic limbs.KEY WORDS: Critical limb ischemia, peripheral arterial disease, position, skin perfusion pressure     

Ultrasound evaluation of fetal brain dysfunction based on behavioral patterns

To identify fetuses at high risk of poor neurological outcomes using a novel ultrasound evaluation system. We assessed an ultrasound evaluation system based on our previous findings, consisting of screening for decreased or lack of fetal movements, abnormal patterns of fetal heart rate, congenital CNS malformations, polyhydramnios of unknown cause, and a “brief ultrasound evaluation” of fetal brain functions, including movement of extremities, breathing movements, ultradian rhythm, REM period, and NREM period. We then assessed the correlation between fetal brain functions and neurological outcomes in infancy (MR, CP, and low Developmental Quotient). During screening, we prospectively evaluated 4978 fetuses receiving prenatal and intrapartum management between January 2000 and December 2009 in our hospital that were later delivered between 32 and 41 weeks’ gestation and identified 93 cases as suspicious for impairment. Of the 93 fetuses, 26 underwent the second step of brief ultrasound examination at 35–40 weeks’ gestation. Our findings revealed that this method was adequately sensitive (80%) and specific (88%) in identifying neurological impairment. We concluded that this method was mainly useful in the clinical setting for establishing the first indication for fetal CNS examination for functional impairment, rendering it suitable for clinical application.