Excessive daytime sleepiness, morning tiredness and major adverse cardiovascular events in patients with chronic coronary syndrome

BACKGROUND

Sleep-related breathing disorders (SRBDs), particularly obstructive sleep apnoea, are associated with increased cardiovascular (CV) risk. However, it is not known whether individual questions used for SRBD screening are associated with major adverse CV events (MACE) and death specifically in patients with chronic coronary syndrome (CCS).

METHODS

Symptoms associated with SRBD were assessed by a baseline questionnaire in 15,640 patients with CCS on optimal secondary preventive therapy in the STABILITY trial. The patients reported the frequency (never/rarely, sometimes, often and always) of: 1) loud snoring; 2) more than one awakening/night; 3) morning tiredness (MT); 4) excessive daytime sleepiness (EDS); or 5) gasping, choking or apnoea when asleep. In adjusted Cox regression models, associations between the frequency of SRBD symptoms and CV outcomes were assessed with never/rarely as reference.

RESULTS

During a median follow-up time of 3.7 years, 1,588 MACE events (541 CV deaths, 749 nonfatal myocardial infarctions [MI] and 298 nonfatal strokes) occurred. EDS was associated (hazard ratio [HR], 95% confidence interval [CI]) with increased risk of MACE (sometimes 1.14 [1.01-1.29], often 1.19 [1.01-1.40] and always 1.43 [1.15-1.78]), MI (always 1.61 [1.17-2.20]) and all-cause death (often 1.26 [1.05-1.52] and always 1.71 [1.35-2.15]). MT was associated with higher risk of MACE (often 1.23 [1.04-1.45] and always 1.46 [1.18-1.81]), MI (always 1.61 [1.22-2.14]) and all-cause death (always 1.54 [1.20-1.98]). The other SRBD-related questions were not consistently associated with worse outcomes.

CONCLUSIONS

In patients with CCS, gradually higher levels of EDS and MT were independently associated with increased risk of MACE, including mortality.

Sleep insufficiency and incidence of cardiovascular disease among adults in Greece

Funding Acknowledgements

Type of funding sources: None.

Introduction

Sleep disorders are an increasing and modifiable risk factor for cardiovascular disease (CVD).

Purpose

The aim of our study was to investigate potential associations between sleep insufficiency and incident CVD.

Methods

In this cross-sectional study, 957 participants, (mean age 49.62 ± 14.79) from the region of Thrace, Greece were enrolled and classified into three groups [short (<6 h), normal (6-8 h) and long (>8 h) sleep duration]. CVD was assessed by a positive response to the following questions: "Have you been told by a doctor that you have had a heart attack or angina (chest pain or exertion that is relieved by medication)?" or "Have you been told by a doctor that you have had a stroke?". Participants’ sleep quality was estimated with the Epworth Sleepiness Scale, Athens Insomnia Scale, Pittsburgh Sleep Quality Index, and Berlin Questionnaire.

Results

The overall prevalence of CVD was 9.5%. The population with CVD exhibited reduced sleep duration and efficiency reduced by 33 min and 10%, respectively. After adjusting for all possible cofounders, short sleep duration was 3.07-times more frequent in patients with CVD and sleep duration of less than 5:33 hours could be a potential risk factor for CVD, especially among females. Additionally, CVD was significantly associated with excessive increased daytime sleepiness, insomnia, poor sleep quality and increased risk of obstructive sleep apnea.

Conclusion(s): Our study depicts a strong correlation of sleep insufficiency with CVD and promotes early pharmacological or cognitive behavioral interventions in order to protect cardiovascular health.

Abstract Figure. Results

Ultra-sensitive refractive index sensor using CMOS plasmonic transducers on silicon photonic interferometric platform

Optical refractive-index sensors exploiting selective co-integration of plasmonics with silicon photonics has emerged as an attractive technology for biosensing applications that can unleash unprecedented performance breakthroughs that reaps the benefits of both technologies. However, towards this direction, a major challenge remains their integration using exclusively CMOS-compatible materials. In this context, herein, we demonstrate, for the first time to our knowledge, a CMOS-compatible plasmo-photonic Mach-Zehnder-interferometer (MZI) based on aluminum and Si3N4 waveguides, exhibiting record-high bulk sensitivity of 4764 nm/RIU with clear potential to scale up the bulk sensitivity values by properly engineering the design parameters of the MZI. The proposed sensor is composed of Si3N4 waveguides butt-coupled with an aluminum stripe in one branch to realize the sensing transducer. The reference arm is built by Si3N4 waveguides, incorporating a thermo-optic phase shifter followed by an MZI-based variable optical attenuation stage to maximize extinction ratio up to 38 dB, hence optimizing the overall sensing performance. The proposed sensor exhibits the highest bulk sensitivity among all plasmo-photonic counterparts, while complying with CMOS manufacturing standards, enabling volume manufacturing.

Plasmonics co-integrated with silicon nitride photonics for high-sensitivity interferometric biosensing

We demonstrate a photonic integrated Mach-Zehnder interferometric sensor, utilizing a plasmonic stripe waveguide in the sensing branch and a photonic variable optical attenuator and a phase shifter in the reference arm to optimize the interferometer operation. The plasmonic sensor is used to detect changes in the refractive index of the surrounding medium exploiting the accumulated phase change of the propagating Surface-Plasmon-Polariton (SPP) mode that is fully exposed in an aqueous buffer solution. The variable optical attenuation stage is incorporated in the reference Si₃N₄ branch, as the means to counter-balance the optical losses introduced by the plasmonic branch and optimize interference at the sensor output. Bulk sensitivity values of 1930 nm/RIU were experimentally measured for a Mach Zehnder Interferometer (MZI) with a Free Spectral Range of 24.8 nm, along with extinction ratio of more than 35 dB, demonstrating the functional benefits of the co-integration of plasmonic and photonic waveguides.

CMOS plasmonics in WDM data transmission: 200 Gb/s (8 × 25Gb/s) transmission over aluminum plasmonic waveguides

We demonstrate wavelength-division-multiplexed (WDM) 200 Gb/s (8 × 25 Gb/s) data transmission over 100 μm long aluminum (Al) surface-plasmon-polariton (SPP) waveguides on a Si₃N₄ waveguide platform at telecom wavelengths. The Al SPP waveguide was evaluated in terms of signal integrity by performing bit-error-rate (BER) measurements that revealed error-free operation for all eight 25 Gb/s non-return-to-zero (NRZ) modulated data channels with power penalties not exceeding 0.2 dB at 10^-9. To the best of our knowledge, this is the first demonstration of WDM enabled data transmission over complementary-metal-oxide-semiconductor (CMOS) SPP waveguides fueling future development of CMOS compatible plasmo-photonic devices for on-chip optical interconnections.

Transradial arterial access catheter knots: how to stay out of trouble

Transradial access has nowadays become a standard of care for percutaneous coronary angiography and intervention. This approach has demonstrated significant reduction in bleeding rate, length of hospital stay, and improvement in clinical outcomes when compared to the traditional transfemoral approach. Due to its advantages this new access is also increasingly being used in non-coronary visceral or peripheral interventions. However, this novel approach may lead to severe catheter kinking and twisting and further manipulation may be required to unravel the catheter and avoid complication. Purpose of this technical review is to present the current techniques and trends in preventing and resolving issues related to radial access catheter kinks.

A high-protein low-fat diet is more effective in improving blood pressure and triglycerides in calorie-restricted obese individuals with newly diagnosed type 2 diabetes

BACKGROUND/OBJECTIVES

There is controversy over dietary protein's effects on cardiovascular disease risk factors in diabetic subjects. It is unclear whether observed effects are due to increased protein or reduced carbohydrate content of the consumed diets. The aim of this study was to compare the effects of two diets differing in protein to fat ratios on cardiovascular disease risk factors.

SUBJECTS/METHODS

A total of 17 obese (body mass index (BMI) ranging from 31 to 45 kg/m(2)) volunteers with type 2 diabetes (DM2), aged 46+/-3 years, consumed two diets, each for 4 weeks, with 3 weeks of washout period in a random, blind, crossover design. The diets were: (1) a high-protein low-fat diet (HP-LF, with 30% protein, 50% carbohydrates and 20% fat) and (2) a low-protein high-fat diet (LP-HF, with 15% protein, 50% carbohydrates and 35% fat). Their effects on fasting glycemic control, lipid levels and blood pressure, and on postprandial glucose and insulin responses after a standard test meal at the beginning and end of each dietary intervention were analyzed.

RESULTS

Both diets were equally effective in promoting weight loss and fat loss and in improving fasting glycemic control, total cholesterol and low-density lipoprotein (LDL) cholesterol, but the HP-LF diet decreased to a greater extent triglyceride (TG) levels (P=0.04) when compared with the LP-HF diet. HP-LF diet improved significantly both systolic and diastolic blood pressure when compared with the LP-HF diet (P<0.001 and P<0.001, respectively). No differences were observed in postprandial glucose and insulin responses.

CONCLUSIONS

A protein to fat ratio of 1.5 in diets significantly improves blood pressure and TG concentrations in obese individuals with DM2.

Accuracy of pulmonary function tests in predicted exercise capacity in COPD patients

PURPOSE

The purpose of this study was to examine exercise tolerance in patients with COPD from measurements of resting pulmonary function parameters.

METHODS

A total of 57 COPD patients were administered the pulmonary function test (PFT) and cardiopulmonary exercise test. The results were analyzed and essentially linear relationships emerged when each subject's VO2 peak was plotted against his individual PFT parameters. Those significant contributors were then introduced in a stepwise multiple regression analysis to determine the best predictor of the VO2 peak.

RESULTS

Stepwise multiple regressions in variables revealed that peak oxygen consumption (VO2 peak) was predicted best by the following equation: VO2 peak=(maximum voluntary ventilation x 0.024)+(forced mid-expiratory flow x 0.47)+(body surface area x 0.988)-0.913 (r=0.90; r2=0.81 SE=0.29 L/min).

CONCLUSION

We conclude that exercise capacity was predicted from measurements of resting pulmonary function parameters with excellent accuracy in the COPD patient.

Bupropion SR for smoking cessation in smokers with cardiovascular disease: a multicentre, randomised study

AIMS

To investigate the safety and efficacy of bupropion sustained release (bupropion SR) in promoting abstinence from smoking in subjects with cardiovascular disease (CVD).

METHODS

Six hundred twenty-nine subjects with CVD who smoked >/=10 cigarettes/day were randomised in a double-blind, multicentre study to receive bupropion SR (150 mg twice daily) or placebo for 7 weeks, with a follow-up of 52 weeks. Primary efficacy endpoint: continuous abstinence from smoking from weeks 4 to 7. Secondary endpoints: continuous abstinence (weeks 4-12, 4-26 and 4-52) and weekly point prevalence abstinence. All participants received brief motivational support. Safety was evaluated throughout the study.

RESULTS

Continuous smoking abstinence rates from weeks 4 to 7 were significantly higher in subjects receiving bupropion SR compared with placebo (43 vs. 19%, odds ratio [OR]=3.27, 95% confidence interval [CI] 2.24-4.84; P<0.001). Continuous abstinence rates from weeks 4 to 26 and 4 to 52 continued to be more than double for bupropion SR compared with placebo (27 vs. 11%; 22 vs. 9%, P<0.001). Weekly point prevalence abstinence was significantly higher for participants who received bupropion SR compared with placebo at weeks 3, 7, 26 and 52 (P<0.001). In both groups, there were no clinically significant changes in blood pressure and heart rate throughout the treatment phase. Overall, 6% of the participants (n=36) discontinued study medication due to an adverse event (bupropion SR, n=17; placebo, n=19).

CONCLUSIONS

After 7 weeks of bupropion SR treatment, more than twice as many smokers with CVD had quit smoking at 1 year compared with placebo. The safety profile of bupropion SR was similar to that previously observed in general smoking populations.

Single-lead VDD-pacing system incorporating high impedance stimulation: a multicentre study

AIM

The purpose of this study was to evaluate the performance of a new VDD pacing system incorporating a high impedance, single-pass VDD lead. The new lead is a bipolar, steroid-eluting, high impedance lead with a full-ring atrial dipole.

METHODS AND RESULTS

The system was implanted in 46 patients with high degree atrioventricular (AV) block. Patients were followed at pre-discharge, 6 weeks, and 3 months. The mean measured P-wave amplitude was stable, with values between 1.18 and 1.43 mV. Atrial sensing was reliable during short-term evaluation at rest and in the sitting position, with AV-synchronous stimulation between 98.79 +/- 6.90% and 99.73 +/- 1.47%. Holter recordings after 6 weeks demonstrated AV-synchronous stimulation in 99.57 1.03% of all P-waves. Lead impedance was stable during follow-up, with mean values between 1000 and 1167 Q. Mean ventricular pacing thresholds (at 0.5 ms) were 0.47 V at implant, 0.49 V at pre-discharge, 0.74 V at 6 weeks, and 0.72 V at 3 months. R-wave amplitude remained stable between 14.9 and 16.7 mV during follow-up.

CONCLUSION

This new single-pass VDD lead system provided reliable atrial sensing and stable high impedance stimulation during a 3-month follow-up period.

Acute effect of clonidine on left ventricular pressure-volume relation in hypertensive patients with diastolic heart dysfunction

We sought to assess the haemodynamic effects of clonidine on left ventricular (LV) pressure-volume relation in patients with diastolic heart dysfunction due to essential hypertension. Towards this end, simultaneous recordings of LV volume (acoustic quantification) and LV pressure (micromanometer) were obtained in 10 such patients before and after drug administration and compared to baseline findings on 10 matched normal controls. The following measurements and calculations were obtained: maximal positive and negative first derivative of LV pressure (peak +dP/dt and peak -dP/dt, respectively), LV minimal and end-diastolic pressure, peak systolic blood pressure, time constant of relaxation (TAU), LV stroke work and LV stiffness constant. The two invasive indexes, LV stiffness constant and TAU classified 10/10 patients as having abnormal LV diastolic function compared with 7/10 patients so classified by Doppler studies. Central sympathetic suppression by a single oral dose of clonidine 0.125 mg in these patients resulted within 60 min in a decrease of heart rate and mean arterial pressure as well as a significant improvement of LV diastolic function indexes. Specifically, the LV stiffness constant (ml(-1)), in normal subjects was 0.0028 vs 0.0152 (P < 0.001) in hypertensive subjects at baseline, vs 0.0053 in hypertensive after clonidine (P < 0.001 vs baseline). Likewise, the E/A ratio, was 1.08 in normal subjects vs 0.88 (P < 0.0001) in hypertensives at baseline, vs 1.28 in hypertensives after clonidine (P < 0.0001 vs baseline). With clonidine the diastolic portion of the pressure-volume curve was displaced downward. In conclusion, clonidine can improve diastolic dysfunction without depressing systolic LV performance. The improvement may be attributable in part to withdrawal of direct sympathetic influence on the myocardium and in part to the indirect effect of systemic, pulmonary and coronary artery relaxation.

Maternal component in the familial aggregation of hypertension

To assess maternal versus paternal contributions to the familial aggregation of hypertension, we examined family history data from 344 hypertensive probands (69 African American, 153 US Caucasian, 122 Greek Caucasian) ascertained without respect to parental hypertension status. The proportion of hypertensive mothers (81.7, 65.0 and 84.8% for African Americans, US Caucasians and Greek Caucasians, respectively) of these probands was significantly greater than the proportion of hypertensive fathers (50.0, 44.9 and 48.3%, respectively) in all three ethnic groups. The lifetime risk of hypertension was significantly greater for mothers compared with fathers of these hypertensive probands (p<0.001). Examination of the proband's siblings indicated that maternal history of hypertension was associated with greater lifetime risk for hypertension than paternal history (p<0.01). In conclusion, we observe a consistent maternal component in the inheritance of hypertension. Although we cannot separate a maternal genetic from epigenetic or environmental effect, our findings suggest that genetic research should include studies of the mitochondrial as well as nuclear genome. Furthermore, when assessing a patient's risk for hypertension, particular attention should be paid to the maternal family history.

Identification of a polymorphic glutamic acid stretch in the alpha2B-adrenergic receptor and lack of linkage with essential hypertension

Essential hypertension, a clinically significant elevation in blood pressure with no recognizable cause, is believed to be attributable to the collective effect of genetic predisposing factors in combination with specific environmental factors, such as diet and stress. Of the genetic causes, genes coding for proteins involved in blood pressure regulation, such as the alpha- and beta-adrenergic receptors, are obvious candidates. The alpha2-adrenergic receptor plays a key role in the sympathetic nervous system by mediating the effects of epinephrine and norepinephrine. To evaluate the potential role between the alpha2B receptor and essential hypertension, we scanned the alpha2B-receptor gene for genetic variation in 108 affected sibling pairs. The screening revealed two major forms of the receptor. They differ by the presence of either 9 or 12 glutamic acid residues in the acidic domain of the third cytoplasmic loop of the protein. Investigation of the pattern of this variation in hypertensive sibling pairs suggests that the alpha2B receptor locus does not contribute substantially to genetic susceptibility for essential hypertension.

Evidence for linkage between essential hypertension and a putative locus on human chromosome 17

Several clinical and animal studies indicate that essential hypertension is inherited as a multifactorial trait with a significant genetic and environmental component. In the stroke-prone spontaneously hypertensive rat model, investigators have found evidence for linkage to blood pressure regulatory genes (quantitative trait loci) on rat chromosomes 2, 10, and X. In 1 human study of French and UK sib pairs, evidence for linkage has been reported to human chromosome 17q, the syntenic region of the rat chromosome 10 quantitative trait loci (QTL). Our study confirms this linkage (P=0.0005) and refines the location of the blood pressure QTL.

Genetic epidemiology of essential hypertension

This review article is intended to introduce the uninitiated clinician to the basic concepts, aims and early findings of the genetic epidemiology of hypertension. It separates the rare monogenic 'Mendelian' hypertensive disorders from the vast majority of patients with essential hypertension, which is a complex, polygenic, multifactorial disorder resulting from interaction of several genes with each other and with the environment. It highlights some clinical strategies used to enhance searches for 'candidates genes', such as subgrouping of populations into relatively homogenous groups or 'intermediate phenotypes' according to presumably heritable anthropometric, clinical or biochemical characteristics; and some applications of genetic epidemiologic techniques, such as linkage and association studies of certain gene polymorphisms with hypertension using affected sibling pairs and large sibships or wide genomic screens comparing affected and unaffected populations. Although so far there is no genotypic variation proven to be causally related to essential hypertension, its intermediate phenotypes or any of its complications, it is hoped that new, more efficient methods of genetic analysis will yield clinically meaningful information.

Beat-to-beat wavelet variance of the QRS complex as a marker of arrhythmogenic substrate in ventricular tachycardia patients

This study proposes a wavelet transform based technique to assess the beat-to-beat variation of the QRS signal in post-myocardial infarction patients with sustained monomorphic ventricular tachycardia. Recent electrophysiological investigations suggested that the diminished synchrony between the normal myocardium and the scarred arrhythmogenic tissue bordering a myocardial infarction area gives rise to beat-variable ECG signal components. Using a mathematical model of small variations in a largely repetitive waveform, we show that the inherent alignment errors (trigger jitter) of the high-resolution ECG (HRECG) can artificially increase the value of the time-domain beat-to-beat variance, making it less valuable as a marker of beat-variable signal components. To overcome this drawback, we propose the wavelet based approach which discriminates between the different factors responsible for the beat variability (the alignment error and the beat-variable signal components). The Morlet wavelet transform is performed on HRECG signals from normal individuals (control group) and postmyocardial infarction patients with documented ventricular tachycardia. Electrical variability is quantitatively assessed via the beat-to-beat wavelet variance measurements. A marker of arrhythmogenic induced variance which achieves a good performance in discrimination of ventricular tachycardia patients from normal subjects was found between 200 Hz and 300 Hz. This finding is in agreement with the proposed mathematical model which states that the useful part of the time-frequency map is shifted upward in a precise mathematical way, as the variance induced by the beat-variable arrhythmogenic signals depend on the frequency characteristics of the first derivative of these signals. We conclude that the dynamics of the arrhythmogenic substrate as revealed by the beat-to-beat wavelet variance can be a new estimator of ventricular tachycardia risk.

Drug therapy for hypertension

By matching the profile of an antihypertensive drug to the clinical and demographic characteristics of the patient (e.g., risk factors, coexisting diseases, goals of therapy beyond lowering blood pressure), the physician can maximize the efficacy of the regimen and minimize the adverse effects the patient may experience. Optimal therapy requires a knowledge of the pharmacologic properties of the six broad classes of antihypertensive drugs: diuretics, sympatholytics (including central and peripheral adrenergic receptor blockers), direct vasodilators, angiotensin-converting enzyme inhibitors, calcium channel blockers and angiotensin II receptor antagonists.

Cardiac electrical instability of the arrhythmogenic tissue substrate assessed by means of wavelet transform

The unstable activation wavefront from the tissue responsible for the production of ventricular tachycardia (VT) gives rise to beat-variable signals components that are eluded during the averaging step of high resolution ECG (HRECG). We used a mathematical model of small variations in a largely repetitive waveform to evaluate the beat-to-beat variance of the HRECG signal. The ability of the Morlet Wavelet Transform to discriminate the different factors responsible for the beat-variability (the alignment error and the beat-variable signal component) has been assessed on simulated signals. The performance evaluation on real ECG signals from normal subjects and patients with a documented history of ventricular tachycardia showed that the dynamics of the arrhythmogenic substrate as revealed by wavelet transform offers a significant improvement in ventricular tachycardia risk assessment.

Effect of antihypertensive treatment on lipids and fibrinogen: Greek multicentre study of cilazapril

The effect cilazapril (CLZ) treatment on serum lipids and fibrinogen was studied in 114 hypertensive patients for 18 weeks. Blood pressure, heart rate, lipid profile and fibrinogen were measured before and at the end of the study in all patients. Satisfactory blood pressure control was seen in 68% of the patients (group A) after 4 weeks of treatment with 5 mg CLZ monotherapy, while a single dose of chlorthalidone, 25 mg daily, was added to the therapeutic regimen of the remaining 32% of patients (group B) to achieve blood pressure control. We conclude that CLZ has a slight beneficial effect on the lipid profile and a significantly beneficial effect on fibrinogen, but its combination with a diuretic reverses this beneficial effect.

Effects of ACE inhibition on the heart

Inhibition of the angiotensin converting enzyme (ACE) results in suppression of the formation of angiotensin II and delay of the degradation of bradykinin. Hence, the pharmacological effects of ACE inhibitors are attributable to both of these mechanisms. This is a brief review of the haemodynamic, neurohumoral and metabolic alterations following ACE inhibition, with an attempt to separate those attributable to the angiotensin-mediated actions and those attributable to bradykinin-mediated actions as they relate to prevention or attenuation of cardiac damage in hypertension, myocardial ischaemia and congestive heart failure.

Pressor hormone profile during stress in hypertension: does vasopressin interfere with left ventricular hypertrophy?

Neurohormonal factors may account for the fact that patients with similar severity and duration of hypertension develop different degrees of left ventricular hypertrophy (LVH). The purpose of this work was to compare the pressor hormone profiles of hypertensive subjects off medication during exercise testing. Nineteen patients, stratified according to echocardiographically diagnosed absence (Group I n = 6) or presence (Group II n = 13) of LVH, underwent testing on the treadmill according to the Bruce protocol. Both groups were comparable in age, severity and duration of hypertension and reached similar double product at peak exercise. Measurements of plasma renin activity (PRA), plasma catecholamines and vasopressin (AVP) at baseline, peak exercise and post exercise revealed significant differences between groups: Group I had suppressed PRA levels throughout and had significantly higher baseline AVP levels, which increased further at peak effort. Group II had significantly higher baseline PRA levels, which tended to increase further at peak effort, and had suppressed AVP levels throughout. There was a significant negative correlation between percent increments in AVP and increments in double product. Norepinephrine increased significantly with effort in both groups, but the levels attained were higher in Group I. In view of the known negative inotropic action of AVP and the trophic effect of angiotensin, we speculate that lower baseline AVP and higher PRA, together with inability of AVP to increase with effort, may be causally related to development of LVH.

Calcification of the tricuspid annulus. Case report and review of the relevant literature

We present a case of tricuspid annulus calcification, documented by fluoroscopy, chest X-ray and cross sectional echocardiography. This case is interesting for two reasons: 1) Tricuspid annulus calcification is extremely rare and very few cases have been reported. 2) It is the third case described where two-dimensional echocardiography established the diagnosis of this very rare condition. Previously reported cases of tricuspid annulus calcification are reviewed.

The detection of delta 9-tetrahydrocannabinol in the breath of human subjects

Delta 9-Tetrahydrocannabinol (THC) was detected in breath of human subjects by gas liquid chromatography/mass spectrometry (GC/MS) up to twelve minutes after smoking marijuana. A number of adsorbents were tested for THC entrapment and subsequent detection (Tenax-GC, ethanol, 0.75 N ethanolic KOH, Amberlite resin XAD-2, and Sephadex G-10). All of these gave poor recoveries. The decay rate of breath THC was much faster than that of plasma THC and there was very poor correlation between breath THC and plasma THC. We conclude that the detection of breath THC is probably due to that emanating from the surface of the mouth and respiratory system.

Purification of rat ceruloplasmin. characterization and comparison with human ceruloplasmin

Rat ceruloplasmin was purified by a three-step column chromatography procedure, utilizing DEAE-Sepharose, Sepharose CL-6B, and CM-Sephadex A50 columns. The molecular weight of rat ceruloplasmin determined by a molecular sieve column was 124,000 daltons. An optical density ratio (610 nm/280 nm) of 0.051 and a molar extinction coefficient of 8600 were obtained. A decrease in lysine in rat ceruloplasmin compared with human ceruloplasmin could account for its reduced anodal mobility. Other differences in the amino acid sequence of the rat ceruloplasmin included an increase in methionine and cystine/cysteine, and a decrease in histidine, tyrosine and tryptophan.