On-line estimation of kinetic parameters in anaerobic digestion using observer-based estimators and multiwavelength fluorometry.

Observer-based estimators (OBE) were used for estimation of state variables and kinetic parameters in an anaerobic digestion (AD) process. A simplified first-order model with time-varying kinetic parameters was used to design an OBE for kinetic parameter estimation. This approach was validated on a laboratory-scale anaerobic reactor equipped with a multiwavelength fluorometer for on-line measurements of COD and VFA concentrations in the reactor effluent. The proposed estimators provide continuous adjustment of kinetic parameters and can be used for predictions of state variables between samples acquisition and during sensor failure.     

Foetal alcohol syndrome in Saskatchewan: unchanged incidence in a 20-year period

Ethers and thioethers of monosaccharides have been synthesised which show potent toxicity to mouse (LD50 > or = 4 g.kg-1 O.W. and 0.2 to 1.5 g.kg-1 I.P.W.). A study of calcium antagonist activity for the full series of compounds indicated that the activity was similar for both O- and S- ethers and maximum activities were observed for monoacetoneglucose ethers possessing carbon chain close to 8 carbons.     

Imitation and pantomime in high-functioning adolescents with autism spectrum disorders

A study was designed to test 2 alternative hypotheses--a symbolic hypothesis and an executive function hypotheses--for the imitation and pantomime deficits found in previous studies of autism. The subjects were 17 adolescent high-functioning subjects with autism spectrum disorders and 15 clinical comparison subjects who were matched on chronological age and verbal IQ. Meaning and sequence were manipulated in facial and manual imitation tasks. Sequence was manipulated in the pantomime and control tasks. Recognition memory and motor control tasks were matched to the experimental tasks. The results provided no support for the symbolic deficit hypothesis; meaning aided rather than hindered the performance of the group with autism. Partial support for the executive deficit hypothesis was found. There were no group differences on motor control tasks, and few on the memory control tasks, arguing against deficits in motor initiation, basic motor coordination, or visual recognition memory.     

In vivo effects of activated H-ras oncogene expressed in the liver and in urogenital tissues

PURPOSE: The clinical significance of isolated calf vein thrombosis (CVT), particularly with respect to development of the postthrombotic syndrome, remains controversial. The purpose of this study was to define the early natural history of CVT in relation to persistent lower extremity symptoms, propagation, recanalization, and the development of valvular incompetence. METHODS: Over a 116-month period, 499 patients with acute deep venous thrombosis (DVT) were referred to our research laboratory, of whom 58 (12%) had thrombosis confined to the calf veins of at least one extremity. The lower extremities of 268 patients (29 with isolated CVT) were followed-up clinically and with duplex ultrasonography at intervals of 1 day, 7 days, 1 month, every 3 months for the first year, and yearly thereafter. RESULTS: Seventy percent of extremities with CVT were symptomatic at presentation. Although the prevalence of clinical signs and symptoms decreased to 29% by 1 month, 23% of patients had persistent pain, edema, or both at 12 months. In contrast, 9% of uninvolved extremities contralateral to a CVT and 54% of extremities with proximal DVT remained symptomatic at 1 year (p = 0.004). Recanalization proceeded rapidly such that the mean thrombus load was reduced by 50% at 1 month and to zero at 1 year. The prevalence of valvular incompetence progressively increased such that reflux was present in 24% of extremities at 1 year. Although its investigation was not a primary goal of this study, pulmonary embolism was diagnosed at presentation and during follow-up in 11% and 3% of patients, respectively. CONCLUSIONS: The natural history of CVT is complicated by persistent symptoms and the development of valvular incompetence in approximately one-quarter of patients. This potential for persistent lower extremity symptoms should be considered in evaluating the clinical relevance of isolated calf vein DVT.     

Effect of pentobarbital on normal brain protection and on the response of 9L rat brain tumor to radiation therapy

The authors attempted to confirm published reports that pentobarbital protects against radiation-induced damage to normal rat brain, as well as enhances radiotherapeutic efficacy in a rat brain tumor model. They evaluated animal survival in 9L gliosarcoma-burdened rats that received whole-brain radiation therapy (16, 24, 32, or 40 Gy) while under intraperitoneal pentobarbital (60 mg/kg) or intramuscular ketamine (60 mg/kg) sedation. The animals were examined at autopsy to attribute death to either intracranial tumor growth or normal brain toxicity in the absence of discernible tumor. There was no difference between the two anesthesia groups regarding the survival of unirradiated animals. Radiation therapy produced a significant dose-dependent prolongation in animal survival, which was limited by the development of normal tissue toxicity at the higher doses. When compared to ketamine anesthesia, pentobarbital anesthesia appeared to offer some protection (not statistically significant) against early (but not late) toxicity at selected radiation doses. A reduction in the number of deaths from tissue toxicity suggested an increased antitumor effect, but again this was not statistically significant. Only in one case was there even a marginal significant difference (p = 0.045) between overall therapeutic efficacy in rats sedated with pentobarbital versus ketamine. While there may be a radioprotective effect of pentobarbital in rat brains without intracranial tumor, there is no conclusive evidence for either radioprotection or significant improvement of radiotherapeutic efficacy in this 9L rat brain tumor model.     

Acute inferior myocardial infarction complicated by rupture into the coronary sinus: diagnosis by two-dimensional echocardiography

Ventricular rupture is a catastrophic, often fatal complication of myocardial infarction. We present a unique case of left ventricular rupture into the coronary sinus that was diagnosed by two-dimensional Doppler echocardiography in a patient with a recent inferior myocardial infarction. The echocardiographic findings essential to diagnosis were subsequently confirmed at autopsy and are reviewed in detail.