Rapid determination of free sulfur dioxide in wine and cider by capillary electrophoresis.

A novel method for the determination of "true" free sulfur dioxide (SO2) in wine and cider was developed using capillary electrophoresis with direct ultraviolet-visible spectrophotometric detection (CE-UV/vis). Free SO2 was measured in model solutions with different SO2-binding agents present (α-ketoglutarate, pyruvate, acetaldehyde, glucose, fructose, and malvidin-3-glucoside) as well as a variety of white and red wines and ciders. The CE method was compared to three conventional methods for measuring free SO2, the Ripper method, Aeration-Oxidation (AO), and pararosaniline by discrete analyzer (DA). While some statistically significant differences (p<0.05) were found between the four methods in unpigmented model solutions and samples, the values generally agreed. In the presence of anthocyanins in model solution and red wines, free SO2 values found by CE were significantly lower than the other three methods (p<0.05). The difference in values found by Ripper and CE correlated strongly with anthocyanin content (R2 = 0.8854) and even more strongly when accounting for polymeric pigments (R2 = 0.9251). The results in red ciders differed from those in red wines, while the CE measured significantly lower free SO2 values than the other three methods, the difference in free SO2 values measured by CE and Ripper correlated more closely with anthocyanin concentration (R2 = 0.8802) than absorbance due to bleachable pigment (R2 = 0.7770). The CE method was found to be rapid (4 min/injection), sensitive (LOD=0.5 mg/L, LOQ=1.6 mg/L free SO2 in wine, 0.8 and 2.8 mg/L, respectively, in cider), robust, and repeatable (average RSD = 4.9%) and did not suffer from the issue of over-reporting free SO2 in pigmented samples often observed with currently accepted methods.

Impact of Dilution on Whisky Aroma: A Sensory and Volatile Composition Analysis.

An "omics"-style approach was used to evaluate the complex relationship between whisky aroma and dilution with water, typically suggested as a way to better appreciate whisky. A set of 25 samples, including Bourbons, ryes, single-malt and blended Scotches, and Irish whiskies were chemically profiled at six dilution levels (100, 90, 80, 70, 60, and 50% whisky/water), while a subset of six whiskies (three Bourbons, three Scotches) at four dilution levels (100, 80, 60, and 40% whisky/water) were chemically profiled and subjected to sensory analysis by a trained panel (n = 20). Untargeted volatile analysis was performed using headspace solid-phase microextraction gas chromatography coupled with mass spectrometry (HS-SPME-GC-MS) and sensory analysis was performed using descriptive analysis (DA). Results were evaluated using multivariate statistical techniques, including multifactor analysis (MFA) and partial least squares discriminant analysis (PLS-DA). Dilution decreased headspace concentration of hydrophilic aroma compounds and increased concentration of more hydrophobic compounds, which agreed with DA results. Dilution above 80% whisky/20% water reduced differences within whisky styles, though differences between American (Bourbon, rye) and Scotch styles (single malt, blended) continued to increase with further dilution. This provides important insight into how dilution of whisky during consumption changes consumer perception, as well as the usefulness of HS-SPME-GC-MS as a proxy for human olfaction.

Mortality from diseases other than cancer following low doses of ionizing radiation: results from the 15-Country Study of nuclear industry workers.

BACKGROUND: Ionizing radiation at very high (radio-therapeutic) dose levels can cause diseases other than cancer, particularly heart diseases. There is increasing evidence that doses of the order of a few sievert (Sv) may also increase the risk of non-cancer diseases. It is not known, however, whether such effects also occur following the lower doses and dose rates of public health concern. METHODS: We used data from an international (15-country) nuclear workers cohort study to evaluate whether mortality from diseases other than cancer is related to low doses of external ionizing radiation. Analyses included 275 312 workers with adequate information on socioeconomic status, over 4 million person-years of follow-up and an average cumulative radiation dose of 20.7 mSv; 11 255 workers had died of non-cancer diseases. RESULTS: The excess relative risk (ERR) per Sv was 0.24 [95% CI (confidence intervals) -0.23, 0.78] for mortality from all non-cancer diseases and 0.09 (95% CI -0.43, 0.70) for circulatory diseases. Higher risk estimates were observed for mortality from respiratory and digestive diseases, but confidence intervals included zero. Increased risks were observed among the younger workers (attained age <50 years, identified post hoc) for all groupings of non-cancer causes of death, including external causes. It is unclear therefore whether these findings reflect real effects of radiation, random variation or residual confounding. CONCLUSIONS: The most informative low-dose radiation study to date provides little evidence for a relationship between mortality from non-malignant diseases and radiation dose. However, we cannot rule out risks per unit dose of the same order of magnitude as found in studies at higher doses.

The 15-Country Collaborative Study of Cancer Risk among Radiation Workers in the Nuclear Industry: estimates of radiation-related cancer risks.

A 15-Country collaborative cohort study was conducted to provide direct estimates of cancer risk following protracted low doses of ionizing radiation. Analyses included 407,391 nuclear industry workers monitored individually for external radiation and 5.2 million person-years of follow-up. A significant association was seen between radiation dose and all-cause mortality [excess relative risk (ERR) 0.42 per Sv, 90% CI 0.07, 0.79; 18,993 deaths]. This was mainly attributable to a dose-related increase in all cancer mortality (ERR/Sv 0.97, 90% CI 0.28, 1.77; 5233 deaths). Among 31 specific types of malignancies studied, a significant association was found for lung cancer (ERR/Sv 1.86, 90% CI 0.49, 3.63; 1457 deaths) and a borderline significant (P = 0.06) association for multiple myeloma (ERR/Sv 6.15, 90% CI <0, 20.6; 83 deaths) and ill-defined and secondary cancers (ERR/Sv 1.96, 90% CI -0.26, 5.90; 328 deaths). Stratification on duration of employment had a large effect on the ERR/Sv, reflecting a strong healthy worker survivor effect in these cohorts. This is the largest analytical epidemiological study of the effects of low-dose protracted exposures to ionizing radiation to date. Further studies will be important to better assess the role of tobacco and other occupational exposures in our risk estimates.

The 15-Country Collaborative Study of Cancer Risk Among Radiation Workers in the Nuclear Industry: design, epidemiological methods and descriptive results.

Radiation protection standards are based mainly on risk estimates from studies of atomic bomb survivors in Japan. The validity of extrapolations from the relatively high-dose acute exposures in this population to the low-dose, protracted or fractionated environmental and occupational exposures of primary public health concern has long been the subject of controversy. A collaborative retrospective cohort study was conducted to provide direct estimates of cancer risk after low-dose protracted exposures. The study included nearly 600,000 workers employed in 154 facilities in 15 countries. This paper describes the design, methods and results of descriptive analyses of the study. The main analyses included 407,391 nuclear industry workers employed for at least 1 year in a participating facility who were monitored individually for external radiation exposure and whose doses resulted predominantly from exposure to higher-energy photon radiation. The total duration of follow-up was 5,192,710 person-years. There were 24,158 deaths from all causes, including 6,734 deaths from cancer. The total collective dose was 7,892 Sv. The overall average cumulative recorded dose was 19.4 mSv. A strong healthy worker effect was observed in most countries. This study provides the largest body of direct evidence to date on the effects of low-dose protracted exposures to external photon radiation.

Risk of cancer after low doses of ionising radiation: retrospective cohort study in 15 countries.

OBJECTIVES: To provide direct estimates of risk of cancer after protracted low doses of ionising radiation and to strengthen the scientific basis of radiation protection standards for environmental, occupational, and medical diagnostic exposures. DESIGN: Multinational retrospective cohort study of cancer mortality. SETTING: Cohorts of workers in the nuclear industry in 15 countries. PARTICIPANTS: 407 391 workers individually monitored for external radiation with a total follow-up of 5.2 million person years. MAIN OUTCOME MEASUREMENTS: Estimates of excess relative risks per sievert (Sv) of radiation dose for mortality from cancers other than leukaemia and from leukaemia excluding chronic lymphocytic leukaemia, the main causes of death considered by radiation protection authorities. RESULTS: The excess relative risk for cancers other than leukaemia was 0.97 per Sv, 95% confidence interval 0.14 to 1.97. Analyses of causes of death related or unrelated to smoking indicate that, although confounding by smoking may be present, it is unlikely to explain all of this increased risk. The excess relative risk for leukaemia excluding chronic lymphocytic leukaemia was 1.93 per Sv (< 0 to 8.47). On the basis of these estimates, 1-2% of deaths from cancer among workers in this cohort may be attributable to radiation. CONCLUSIONS: These estimates, from the largest study of nuclear workers ever conducted, are higher than, but statistically compatible with, the risk estimates used for current radiation protection standards. The results suggest that there is a small excess risk of cancer, even at the low doses and dose rates typically received by nuclear workers in this study.

Sickle cell disease and tonsillectomy. Preoperative management and postoperative complications.

BACKGROUND: Patients with sickle cell disease are recognized as having a relatively higher risk for postoperative complications, including fever, atelectasis, pneumonia, or sickle cell vas-occlusion. OBJECTIVE: To present a protocol for preoperative management of patients with sickle cell disease undergoing tonsillectomy, including the use of transfusions and intravenous hydration. DESIGN: Retrospective chart review. SETTING: Academic, tertiary care referral medical center. PATIENTS: Seventy-five patients with sickle cell disease who underwent tonsillectomy with or without adenoidectomy were included for review. Preoperative management was documented, and risk factors were assessed. Intraoperative management was reviewed, and postoperative complications were identified and compared with preoperative data and management. RESULTS: Preoperative management consisted of transfusions to a hemoglobin S ratio (hemoglobin S-total hemoglobin) less than 40% or a hemoglobin level greater than 100 g/L. Aggressive intravenous hydration of 1.5 times the maintenance fluid was given 24 hours before surgery. Increased complications were associated with a preoperative hemoglobin S ratio greater than 40% (P < .05) and an age younger than 4 years (P < .05). Operative time, technique, and blood loss were not statistically significant risk factors. The average length of hospitalization was 4.8 days. CONCLUSIONS: Children with sickle cell disease presenting for elective tonsillectomy should be given a transfusion to a hemoglobin S ratio less than 40% in an attempt to reduce postoperative complications. Additional factors, such as age and presence of obstructive sleep apnea, only increase the potential risks.

Rhabdomyosarcoma arising within congenital pulmonary cysts: report of three cases.

Over the past 9 months, three cases of primary pulmonary rhabdomyosarcoma have been treated at British Columbia Children's Hospital. Two patients (aged 24 and 37 months) presented with spontaneous pneumothoraces and had cystic changes in the affected lung on chest radiograph. The third patient (aged 42 months) was evaluated for chronic cough, fever, and failure to thrive. Chest x-ray showed a large mass in the left lower lobe as well as mediastinal adenopathy. All three of these lesions originated within congenital lung cysts, one a peripheral bronchogenic cyst and the others cystic adenomatoid malformations. This report suggests that there is a significant risk for the development of rhabdomyosarcoma within malformed pulmonary tissue.

Myocardial oedema and ventricular function after cardioplegia with added mannitol.

Myocardial oedema may contribute to the impaired myocardial performance which commonly follows open heart surgery with cardioplegia-induced cardiac arrest. The rate of oedema formation during crystalloid cardioplegia and the relation of this to changes in ventricular compliance and ventricular function following reperfusion were studied using an isolated rabbit heart preparation. Myocardial tissue water content increased during cardioplegic arrest and the water content prior to reperfusion demonstrated an inverse correlation with ventricular function after reperfusion. In further studies the effect of adding mannitol to a standard crystalloid cardioplegic solution was investigated. The preparations were divided into two groups: nine were administered a standard cardioplegic solution (Plegisol*) (control group) and a further eight were administered the same solution mixed with mannitol to adjust the osmotic pressure to 360 mOsmol.L-3 (mannitol group). The mannitol group demonstrated less increase in RV water content and superior LV dP/dtmax following reperfusion. It is concluded that mannitol enhances protection of the myocardium during cardioplegic cardiac arrest.

The effect of desmopressin acetate (DDAVP) on postoperative blood loss after cardiac operations in children.

We investigated the effect of an intraoperative desmopressin acetate infusion on blood loss after cardiac operation in 60 children, by using a prospective, randomized, double-blind trial. Thirty patients received a desmopressin dose of 0.3 microgram/kg intravenously over 15 minutes at the conclusion of cardiac bypass, and 30 received a saline placebo. The two groups were comparable with respect to age, sex, cardiac lesion, presence of cyanosis, and prevalence of Down's syndrome. Results showed no significant difference in postoperative blood loss between the two groups (30.5 +/- 37.9 ml/kg in the placebo group versus 40.0 +/- 33.1 ml/kg in the desmopressin group). Postoperative bleeding time, total urine output, postinfusion hemodynamics, and postoperative coagulation studies did not differ significantly between the two groups. We conclude that postbypass desmopressin infusion does not reduce blood loss in children undergoing cardiac operations.

Influence of echocardiography in pre-operative cardiac catheterization in congenital heart disease.

The influence of echocardiography on pre-operative cardiac catheterization was assessed in a retrospective analysis comparing two 12-month periods. Of 245 operations in 1983, 200 (82%) had pre-operative cardiac catheterization when two-dimensional echocardiography only was used in the pre-operative assessment compared to 162 of 238 (68%) operations in July 1985-June 1986 when pulsed Doppler echocardiography also was used (P less than 0.001). Significant reductions in pre-operative cardiac catheterization were present in both open (87/87 vs 89/102, P less than 0.001) and closed (113/158 vs 73/136, P less than 0.005) heart procedures. The group with the most significant reduction in pre-operative cardiac catheterization before open heart surgery were children with atrial septal defects; of the closed heart surgical groups, the greatest reductions were in patent ductus arteriosus, coarctation of the aorta and tetralogy of Fallot. Echocardiogram diagnostic errors occurred in 22/245 (9%) in 1983 compared to 9/238 (4%) in 1985/86 (P less than 0.05). Echocardiography has resulted in a significant reduction in pre-operative cardiac catheterization and has become more accurate in diagnosis.

Left ventricular systolic and diastolic function after two-stage anatomic correction of transposition of the great arteries.

Anatomic repair of transposition of the great arteries (TGA) has been developed because of concerns about right ventricular function after atrial repair by the Mustard or the Senning technique. This study assessed left ventricular systolic and diastolic function in three patients after two-stage anatomic repair. Two patients had a ventricular septal defect (one with coarctation), and the third patient had right ventricular dysfunction precluding atrial repair. All had pulmonary artery banding. The mean ages at the time of repair and catheterization were 2.75 and 4.9 years, respectively. The control group included 10 patients with insignificant or no cardiac disease. At cardiac catheterization the group with TGA had a higher mean end-diastolic volume index (110.9 +/- 4.74 ml/m2) compared to normal subjects (79.1 +/- 14.55; p less than 0.001), mean end-systolic volume index (37.3 +/- 3.69 vs 22.7 +/- 4.42; p less than 0.001), mass index (101.0 +/- 16.9 vs 68.2 +/- 12.34; p = 0.038), and stroke volume index (73.6 +/- 3.52 vs 56.5 +/- 12.1; p = 0.0027). The ejection fractions, end-diastolic and peak systolic pressures, and stresses were not different. There was no difference in the relationship between the mean rate-corrected velocity of circumferential fiber shortening and end-systolic stress for the group with TGA, but myocardial stiffness was markedly elevated (29.5 +/- 1.84 vs 10.8 +/- 2.20; p less than 0.001). Thus, this study found abnormalities of left ventricular size after two-stage anatomic repair of TGA in this group of patients with TGA.(ABSTRACT TRUNCATED AT 250 WORDS)

Total anomalous pulmonary venous return with left heart hypoplasia.

A term baby had a total anomalous pulmonary venous return to the inferior vena cava. The infant underwent complete repair, but died 30 hours after operation. The postmortem examination revealed severe endocardial fibroelastosis. This uncommon association is discussed.

Pulmonary artery banding: results and current indications in pediatric cardiac surgery.

The results of pulmonary artery banding in 144 patients seen from 1971 to 1984 were reviewed. Age ranged from 1 week to 4 years (median, 8 weeks) and weight, from 1.1 to 16 kg (median, 4 kg). The patients were divided into three major groups: Group 1, defects without mixing disorders (ventricular septal defect, double-outlet right ventricle [DORV], atrioventricular septal defect); Group 2, defects with mixing disorders (transposition of the great arteries, DORV, single ventricle, tricuspid atresia); and Group 3, miscellaneous (mitral atresia, left ventricular hypoplasia, truncus complex). The diagnostic group influenced survival (p = 0.0035). In Group 1, 88.8% survived, but only 64.9% survived in Groups 2 and 3 combined. The presence of patent ductus arteriosus or coarctation of the aorta had no effect on survival (p = 0.61 and p = 0.7, respectively). The clinical condition at thirty days after pulmonary artery banding was good in 35.1% and fair in 46.9% of the patients. When the data were divided into the three periods 1971 through 1974, 1975 through 1979, and 1980 through 1984, which included 28, 49, and 67 patients, respectively, a significant improvement in survival was observed from the early (64.3%) to the late period (92.5%) (p = 0.0009). Patients weighing less than 4 kg had a significantly lower survival in the period 1971 through 1974 (37.5% versus 91.67%). No significant difference in survival was detected in the late period, 1980 to 1984 (90% versus 94.6%), between patients weighing less than and those weighing more than 4 kg. Pulmonary artery banding is clinically satisfactory in small infants and children with complex anomalies.

Left ventricular systolic and diastolic function after total correction of tetralogy of Fallot.

Left ventricular (LV) systolic and diastolic function was assessed in 12 patients after total correction of tetralogy of Fallot (age range 5 to 18 years, mean 10) and compared with 10 control patients. Only 1 patient had a shunt before total correction that was performed at a mean age of 3.5 years, (range 0.3 to 8). At cardiac catheterization the following indexed LV parameters were measured: end-diastolic and end-systolic volumes, wall mass, ejection fraction, stroke volume and end-diastolic and end-systolic pressures and stresses. The rate-corrected mean velocity of fiber shortening was calculated. LV diastolic operant chamber stiffness and myocardial stiffness were calculated from simultaneous diastolic pressures and volumes in mid- and late diastole using monoexponential formulas. The 2 groups were compared by unpaired t tests. The tetralogy group had higher mean end-diastolic (93 vs 74 ml/m2), end-systolic (29 vs 19 ml/m2) and stroke (64 vs 55 ml/m2) volumes than controls. Rate-corrected mean velocity of fiber shortening was lower in the tetralogy group (1.07 vs 1.24). Myocardial stiffness was higher in the tetralogy group (16 vs 11). Other indexes were not significantly different. Thus, LV function after total correction of tetralogy of Fallot may be abnormal with larger than normal LV size, decreased contractile function and increased myocardial stiffness.

Experience with polytetrafluoroethylene grafts in children with cyanotic congenital heart disease.

Survival and event-free rates of 47 polytetrafluoroethylene (PTFE) (Gore-Tex) shunts for severe cyanotic congenital heart defects were studied in 42 children from April, 1981, to March, 1983. Retrospective actuarial analysis was conducted over the 27 months of the study in 3-month intervals of the follow-up. The estimated actuarial patient survival at two years was 86% with an estimated actuarial event-free rate of 57.2%. The grafts were found to be patent in 89% (42/47) of the grafts. Complications associated with PTFE grafts were thrombosis, infections, heart failure, shunt stenosis, and deformity of the pulmonary arteries. Polytetrafluoroethylene grafts for systemic-pulmonary shunts offer good palliation, but the frequency of complications indicates that close follow-up is mandatory to avoid or treat serious sequelae of the complications.

Successful palliation by pulmonary artery banding in absent pulmonary valve syndrome with aneurysmal pulmonary arteries.

Three infants with absent pulmonary valve syndrome were treated between 1977 and 1980. All infants were in critical cardiorespiratory failure refractory to medical therapy. Pulmonary artery banding was performed to reduce the volume occupied by the large pulsating pulmonary artery in a limited mediastinal space. The band reduced tracheobronchial compression and increased effective cardiac output. All three infants survived the procedure and, at follow-up, significant improvement in cardiorespiratory function has been noted, with satisfactory growth. This experience suggests that pulmonary artery banding has a place in the initial management of absent pulmonary valve syndrome, allowing survival so that total correction can be undertaken more safely at a later stage.