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Antibiotic formulation effluent is well known for its important contribution to environmental pollution due to its fluctuating and recalcitrant nature. In the present study, the chemical treatability of penicillin formulation effluent (average filtered COD(o)=830 mg/l; average soluble COD(o)=615 mg/l; pH(o)=6.9) bearing the active substances penicillin Amoxicillin Trihydrate (C(16)H(19)N(3)O(5)S.3H(2)O) and the beta-lactamase inhibitor Potassium Clavulanate (C(8)H(8)KNO(5)) has been investigated. For this purpose, the penicillin formulation effluent was subjected to ozonation (applied ozone dose=2500 mg/(lxh)) at varying pH (2.5-12.0) and O(3)+H(2)O(2) (perozonation) at different initial H(2)O(2) concentrations (=2-40 mM) and pH 10.5. According to the experimental results, the overall Chemical Oxygen Demand (COD) removal efficiency varied between 10 and 56% for ozonation and 30% (no H(2)O(2)) and 83% (20 mM H(2)O(2)) for the O(3)+H(2)O(2) process. The addition of H(2)O(2) improved the COD removal rates considerably even at the lowest studied H(2)O(2) concentration. An optimum H(2)O(2) concentration of 20 mM existed at which the highest COD removal efficiency and abatement kinetics were obtained. The ozone absorption rate ranged between 53% (ozonation) and 68% (perozonation). An ozone input of 800 mg/l in 20 min was sufficient to achieve the highest BOD(5)/COD (biodegradability) ratio (=0.45) and BOD(5) value (109 mg/l) for the pre-treated penicillin formulation effluent. After the establishment of optimum ozonation and perozonation conditions, mixtures of synthetic domestic wastewater+raw, ozonated and perozonated penicillin formulation effluent were subjected to biological activated sludge treatment at a food-to-microorganisms (F/M) ratio of 0.23 mg COD/(mg MLSSxd), using a consortium of acclimated microorganisms. COD removal efficiencies of the activated sludge process were 71, 81 and 72% for pharmaceutical wastewater containing synthetic domestic wastewater mixed with either raw, ozonated or perozonated formulation effluent, respectively. The ultimate COD value obtained after 24-h biotreatment of the synthetic domestic wastewater+pre-ozonated formulation effluent mixture was around 100 mg/l instead of 180 mg/l which was the final COD obtained for the wastewater mixture containing raw formulation effluent, indicating that pre-ozonation at least partially removed the non-biodegradable COD fraction of the formulation effluent.

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The value of high frequency QRS potentials (HFQRS) during acute myocardial infarction (AMI) was assessed to define infarct size and prognosis. HFQRS were recorded by signal-averaged ECG with 150-250 Hz frequency ranges, using X, Y, Z orthogonal leads. Recordings were obtained in surviving AMI patients (n = 33, 12 inferior, 11 anterior, 10 anterior-inferior) on the first and tenth days, but in non-survived patients (n = 5, 2 inferior, 1 anterior, 2 anterior-inferior) only on the first day. Additionally, the frequency of ventricular tachycardia (VT) was evaluated by 24-h Holter monitoring in all patients at the same days. The control group consisted of 11 healthy people. In surviving AMI patients, RMS voltage of vector magnitude reduced in anterior and anterior-inferior MI but filtered QRS duration was longer in inferior MI than normals (P < 0.05, < 0.05, < 0.01, respectively). In nonsurvived patients, RMS voltages of leads X, Y, Z and vector magnitude were lower than normals (P < 0.01, < 0.05, < 0.01, < 0.01, respectively) and surviving AMI patients (P < 0.01, < 0.05, < 0.05, < 0.05, respectively), the filtered QRS duration was found to be longer than normals and survived patients (P < 0.01, < 0.01). In patients who had VT on Holter monitoring, filtered QRS duration was significantly longer than in patients without VT (P < 0.05). As a result, HFQRS was important for defining infarct size but not malignant ventricular arrhythmias. VT was related to filtered QRS duration. HFQRS may offer significant prognostic information and contribute to early risk stratification of AMI patients.

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Heart rate variability (HRV) is a noninvasive index of the neural activity of the heart. Although also influenced by the sympathetic activity of the heart, HRV is essentially determined by the vagal stimulation of the heart. Several HRV abnormalities have been described in adults with diabetes mellitus. However, there are few data on HRV in children with diabetes mellitus. In the present study, HRV was assessed in seven healthy children, 10 diabetic children with good glycemic control and 11 diabetic children with poor glycemic control. All had normal standard cardiac autonomic function tests, obtained from 24-h Holter tapes. HRV was measured by calculating six time-domain (mean R-R interval (RR), standard deviation of the R-R interval [SDRR], standard deviation of the mean of 288 R-R intervals [SDANN], the mean of the 288 standard deviations computed for each 5-min period [SD], percentage of differences of adjacent R-R intervals of > 50 msec for the entire 24 h [pNN50], and the root mean square of successive differences [rMSSD]) and four frequency-domain (low frequency [LF], high frequency [HF], total heart rate power spectra, and LF/HF ratio) indexes. SD, pNN50, rMSSD, LF, HF and total heart rate power spectra were markedly and significantly reduced in diabetic children with poor metabolic control. The 24-h variation of low- and high-frequency components of heart rate power spectra of the latter children had a different shape. Thus, diabetic children with poor metabolic control (elevated HbA1c and B2M levels) have a low HRV compared to those diabetic children with good control and healthy children.(ABSTRACT TRUNCATED AT 250 WORDS)

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