Evaluation of the prediction of micropollutant elimination during bromide ion-containing industrial wastewater ozonation using the ROH, O3 value

The composition of the wastewater matrix influences the oxidation potential of ozonation, a technique widely recognized efficient removal of micropollutants. Here, we developed a chemical kinetic model to determine the ozone dose required to minimize bromate production in wastewater containing bromine ions while achieving target removal rates. In wastewater ozonation, ozone decomposition comprises instantaneous ozone consumption and subsequent decomposition at first-order reaction rates. Under the injection condition of 1.5 g O3/g dissolved organic carbon (DOC), the instantaneous ozone demand was 62.7% of the injection concentration, and it increased proportionally with increasing injected ozone concentration. Ozone and hydroxyl radical exposures were proportional to the initial ozone dose, while hydroxyl radical exposure was proportional to ozone exposure, and the deviation was relatively high at 1.0-1.5 g O3/g DOC. The calculated hydroxyl radical exposure was 3.0 × 10-10 to 5.3 × 10-10 M s. Ozone and hydroxyl radicals are highly correlated with the ratio of ozone dose to organic matter concentration. Therefore, a trace substance removal rate evaluation model combined with the ROH, O3 model and a bromate generation model were also considered. For ibuprofen, the ozone dose for achieving the target removal rate of 80% while maintaining the bromate concentration below 50 μg L-1 was suitable in the operating range of 0.86 g O3/g DOC or more. The proposed method provides a practical operation strategy to calculate the appropriate ozone dose condition from the target compound removal rate prediction and bromate generation models considering the ratio of ozone dose to organic matter concentration in the incoming wastewater.

Electronic tongue for the simple and rapid determination of taste and odor compounds in water

Taste and odor (T&O) compounds present in natural water bodies could originate from algae. In this study, alga-generated compounds that can cause T&O issues in water, such as geosmin (GE), 2-Methylisoborneol (MIB), 2,4,6-Trichloroanisole (TCA), 2-Methylbenzofuran (MB), 2-Isopropyl-3-methoxypyrazine (IPMP), 2-Isobutyl-3-methoxypyrazine (IBMP), cis-3-Hexenyl acetate (HA), trans,trans-2,4-Heptadienal (HD), trans,cis-2,6-Nonadienal (ND), and trans-2-Decenal (DN), were determined through solid-phase microextraction coupled with gas chromatography/mass spectrometry (HS-SPME GC/MS) and electronic tongue (E-tongue), and the results from the two techniques were compared. Although HS-SPME GC/MS facilitates the detection and quantification of T&O compounds with high precision and accuracy, the sample preparation and handling is difficult and the analysis time (1 h) is longer than those of other analytical methods. E-tongue can be used as an alternative analytical method for water quality analysis and risk management because it enables controlled and rapid analysis (3 min) of T&O compounds in water at a low cost. Notably, principal component analysis indicated that E-tongue can discriminate and quantify eight T&O compounds at as low as 0.02 μg L-1 concentration. Further, partial least squares analysis confirmed that the sensor exhibits high sensitivity to concentration changes. The sensors with the highest variable importance in projection scores were determined to be SCS (1.39 and 1.38) for GE and MIB, CTS (1.34) for IPMP, CPS (1.33) for IBMP, AHS (1.42) for HA, ANS (1.22) for HD, and NMS (1.14 and 1.19) for ND and DN.

Fluorescence excitation-emission matrix spectroscopy coupled with parallel factor analysis to determine chlorine decay constants in urban water distribution system

This study applied a method for estimating chlorine decay constant (k) in urban water distribution systems using fluorescence excitation-emission matrix spectroscopy-parallel factor analysis (FEEM-PARAFAC), considering that it accounts for the influence of organic matter in the target area. The simultaneous impacts of seasonal variations on chlorine consumption and dissolved organic matter (DOM) composition were investigated for a year in three full-scale water distribution systems in I city (areas S, K, and G). Bulk decay constants (kb) were obtained through bottle tests, and the kb value was observed to differ by season and significantly affected by temperature. It exhibited its highest value, 0.794 d^-1, in summer at area G. As a result of analyses through F-EEM-PARAFAC, it was determined that the components of the target raw water were humic-like and tryptophan-like. The quantitative analysis of organic substances through PARAFAC revealed that area G had the highest score (C1+C2) than other areas. 11.568, 10.578, and 11.771 in summer at areas S, K, and G, respectively. The model equations were derived such that the significant (R2 = 0.85-0.95) correlation between the C1 and C2 model scores and total chlorine decay constants (kt) verified via PARAFAC analysis of the target raw water was considered. Furthermore, a method for obtaining the wall decay constants at a target point based on the correlation equation was investigated.

Comparative evaluation of 2-isopropyl-3-methoxypyrazine, 2-isobutyl-3-methoxypyrazine, and 2,4,6-trichloroanisole degradation by ultraviolet/chlorine and ultraviolet/hydrogen peroxide processes

2-Isopropyl-3-methoxypyrazine (IPMP), 2-Isobutyl-3-methoxypyrazine (IBMP), and 2,4,6-Trichloroanisole (TCA) are the primary emerging taste and odor (T&O) compounds in water systems with low thresholds (ng L^-1). The selected T&O compounds are known to be difficult to remove using conventional water treatment processes. In this study, we compared the removal characteristics of the three T&O compounds using UV/Cl₂ and UV/H₂O₂. The removal rates of the three compounds by direct photolysis at 254 nm were less than 10%, even at a high UV dose (approximately 1000 mJ cm^-2). Under conditions of an oxidant injection volume of 5 mg L^-1 and UV dose of 1000 mJ cm^-2, the degradation rate of the target compounds in the UV/H₂O₂ process exceeded that of the UV/Cl₂ process. Moreover, the results revealed that pH has a significant impact on the removal of the T&O compounds during the UV/Cl₂ process. The IPMP, IBMP, and TCA were found to be more reactive with hydroxyl radicals than reactive chlorine species (RCS). A predictive tool was developed to determine the optimal operating condition using the generalized reduced gradient (GRG) nonlinear solver. In the UV/H₂O₂ process, the EED value for 90% removing rate was 0.156 kWh m^-3 for the IPMP, 0.135 kWh m^-3 for the IBMP, and 0.154 kWh m^-3 for the TCA, respectively. In case of the UV/Cl₂, the EED value for 50% removing rate was 0.174 kWh m^-3 for the IPMP, 0.138 kWh m^-3 for the IBMP, and 0.169 kWh m^-3 for the TCA, respectively.

Hydroxyl radical scavenging factor measurement using a fluorescence excitation-emission matrix and parallel factor analysis in ultraviolet advanced oxidation processes

The performance of the UV/H₂O₂ advanced oxidation process (AOP) is dependent on water quality parameters, including the UV absorbance coefficient at 254 nm and hydroxyl radical (•OH) water background demand (scavenging factor, s^-1). The •OH scavenging factor represents the •OH scavenging rate of the background substances in the water matrix, and it is known to be one of the key parameters to predict the performance of the UV/H₂O₂ process. The •OH scavenging factor has been determined experimentally by using a probe compound such as pCBA and rhodamine B. The experimental method has been validated to accurately predict the micropollutants removal in the UV/H₂O₂ process, but there is a need for an easier and simple method of determining the OH scavenging factor. We evaluated the alternative method to analyze the •OH scavenging factor using fluorescence excitation-emission matrix and parallel factor analysis (F-EEM/PARAFAC). The correlation between •OH scavenging factor and the spectroscopic characteristics and structure of different organic matter types was evaluated. Organic matter was characterized using a fluorescence excitation-emission matrix, parallel factor analysis, and liquid chromatography-organic carbon detection. Second-order reaction rates of humic acid sodium salt, sodium alginate, Suwannee River humic acid and bovine serum albumin were calculated as 1.30 × 10⁸ M^-1 s^-1, 1.39 × 10⁸ M^-1 s^-1, 1.03 × 10⁸ M^-1 s^-1, and 3.17 × 10⁷ M^-1 s^-1, respectively. Results of PARAFAC analysis, the ratio of humic and fulvic fluorescence component 2 to terrestrial humic-like fluorescence component 1 (C2/C1), and •OH scavenging factor showed high linearity. A predictive model, which combines with the F-EEM/PARAFAC method, predicted the optimal UV and H₂O₂ dose to achieve target compound removal.

Association of angiotensin I converting enzyme gene polymorphism with reflux nephropathy in children

Deletion polymorphism of angiotensin I converting enzyme (ACE) gene has been studied as a risk factor in various cardiovascular diseases and chronic nephropathies. Perturbation of local and systemic renin-angiotensin systems is one of the possible mechanisms of the progression of reflux nephropathy. In this study, the implication of ACE gene polymorphism in renal scarring and deterioration of renal function was analyzed in 66 children with vesicoureteral reflux. The genotype for the polymorphism was determined by PCR, and renal scar was identified by (99m)Tc-DMSA renal scan. The allelic frequency of the deletion polymorphism showed no significant difference either between patients with normal renal function and those with decreased renal function or between patients with renal scar and those without. We conclude that deletion polymorphism of ACE gene, as an independent variable, is not associated with reflux nephropathy in children with vesicoureteral reflux.

Cationic liposome-enhanced adenoviral gene transfer in a murine head and neck cancer model

The effect of combining adenoviral vector and cationic liposomes on the efficiency of gene transfer to head and neck tumor cells was investigated. Two human and two murine cell lines were used for the screening of gene transfer efficiency using an adenoviral vector. Cationic liposome-enhanced gene transfer was checked using a murine squamous carcinoma cell line, SCCVII/SF. A considerable difference in the efficiency of gene transduction was observed among the cell lines. The combination of DOSPER and adenoviral vector containing human alkaline phosphatase showed a remarkable enhancing effect in gene transfer in vitro and in vivo, compared to the adenovirus alone or control groups. With an improvement in the efficiency of gene transfer, it may be possible not only to enhance the expression of transduced genes, but also to deliver a smaller amount of virus, as a result, reducing toxicity and the immune response against adenovirus.

Expression of heat shock protein 72 in rat cochlea with cisplatin-induced acute ototoxicity

Cisplatin ototoxicity is known to involve mainly the organ of Corti. Outer hair cells (OHCs). especially in the basal turn, are preferentially involved. One possible mechanism of ototoxicity might be alteration of the antioxidant system causing an increase in free radicals. It has been demonstrated that heat shock proteins (HSPs), which are believed to protect cells by dissolving and refolding misfolded or denatured protein are induced by various form of stress. HSP is also demonstrated to be induced by free radicals. The purpose of this study was to evaluate HSP 72 induction in cochlea following cisplatin injection in the animal model. Sprague-Dawley (SD) rats were injected intraperitoneally with normal saline as control or cisplatin at a dose of 5, 10 or 20 mg/kg. Cochleae were harvested 1, 3, 6 and 12 h after injection and compared with those of controls. Immunocytochemical study with surface preparation and Western blotting were performed to investigate the expression of HSP 72. Auditory brainstem response (ABR) was also recorded to assess functional change according to the dosage of cisplatin and duration after injection. In the 5 and 10 mg/kg groups, immunostaining for HSP 72 in the OHCs reached a plateau level at 3 h, which was maintained until 12 h after injection. The amount of immunoreactive OHCs in the 20 mg/kg group was smaller than those in 5 and 10 mg/kg groups and declined after 6 h. The bands for HSP 72 became less intense as the cisplatin dosage increased from 5 to 10 and 20 mg/kg in Western blotting. The change in ABR threshold was small in the 5 and 10 mg/kg groups and a marked change in threshold was observed in the 20 mg/kg group. Detection of HSP 72 after cisplatin injection could confirm the OHCs as one of the major injured cells in the cochlea. With a lethal dosage of cisplatin (20 mg/kg), HSP 72 expression was less prominent and declined after 6 h.

Neoadjuvant chemotherapy and radiotherapy for the treatment of advanced hypopharyngeal carcinoma

PURPOSE

To evaluate the efficacy of the neoadjuvant chemotherapy and radiation therapy in treatment of patients with advanced hypopharyngeal cancer, which is notorious for its poor prognosis and severe surgical morbidity with functional deficits.

MATERIALS AND METHODS

Medical records of 62 patients with squamous cell carcinoma of the hypopharynx, Stage III or IV (AJCC, 1992), were retrospectively reviewed.

RESULTS

Neoadjuvant chemotherapy showed an overall response rate of 87% and a complete remission (CR) rate was 67% following chemotherapy and radiation therapy. The patients who did not show CR after chemotherapy had a high likelihood of treatment failure, even though they achieved CR following subsequent radiotherapy. Thirteen of 30 patients were able to preserve their larynges for more than 3 years by chemotherapy and radiation.

CONCLUSION

This approach appeared to be as effective as radical surgery with postoperative radiation therapy without comprising survival. To improve the cure rates, we need to develop better strategies to increase CR rates with chemotherapy and determine the best treatment option for patients who are partially or nonresponsive to chemotherapy.

The association of cigarette smoking and alcohol consumption with other cardiovascular risk factors in men from Seoul, Korea

PURPOSE

To explore the effects of cigarette smoking and alcohol consumption on cardiovascular disease risk factors such as hypertension, dyslipidemia, and glucose intolerance in Korean men.

METHODS

In this cross-sectional study, we gathered the smoking and drinking history by self-administered questionnaire between June 1994 and May 1995 among 1053 men, age 20-77, who visited a prevention center for a multiphasic health check at St. Mary's Hospital, Seoul.

RESULTS

Cigarette smoking had a significant inverse association with systolic and diastolic blood pressure. Adjusted for age, body mass index (BMI), and alcohol consumption, the odds ratio of hypercho-lesterolemia (> or = 240 mg/dl) was 1.30 (95% confidence interval (CI) 1.09-1.55), lower high density lipoprotein (HDL) cholesterol (< 40 mg/dl) was 1.29 (95% CI 1.08-1.54), higher low density lipoprotein (LDL) cholesterol (> or = 160 mg/dl) was 1.30 (95% CI 1.07-1.56), and hypertriglyceridemia (> or = 200 mg/dl) was 1.40 (95% CI 1.16-1.68) among men who smoked 21-30 cigarettes per day compared with nonsmokers. Adjusted for age. BMI, and cigarette smoking in men who consumed 90-179 and 180-269 g/week of alcohol compared with nondrinkers, the odds ratio of hypertension was 1.73 (95% CI 1.01-3.00) and 1.48 (95% CI 1.01-2.17), respectively. Alcohol consumption had a significant protective effect (adjusted odds ratio: 0.60-0.78) against lower HDL cholesterol in all categories > or = 90 g of alcohol per week compared with nondrinkers. The adjusted odds ratio of hypertriglyceridemia was 1.17 (95% CI 1.04-1.31), and glucose intolerance (fasting blood sugar (FBS) > or = 120 mg/dl) was 1.27 (95% CI 1.11-1.14) among those who consumed > or = 360 g/week of alcohol compared with nondrinkers.

CONCLUSIONS

In this Korean population study, although alcohol consumption increased HDL cholesterol, which might have a protective effect on coronary heart disease, cigarette smoking was associated with decreased blood pressure, smoking was confirmed to have dyslipidemic effect such as increasing total cholesterol, LDL cholesterol, triglyceride and decreasing HDL cholesterol, and alcohol consumption was confirmed to be associated with hypertension, hypertriglyceridemia, and glucose intolerance as in Caucasian. Further prospective intervention studies are needed for evaluating cardiovascular effects after cessation of smoking and drinking.

Intussusception associated with Yersinia pseudotuberculosis infection

Intussusception associated with Yersinia pseudotuberculosis infection was developed in three boys; two of them had a history of drinking untreated water. All intussusceptions were localized at the ileocolic region, and all patients completely recovered with Gastrografin enema and supportive treatment without complication and operation.

Acute renal failure associated with Yersinia pseudotuberculosis infection in children

We report 45 pediatric cases of Yersinia pseudotuberculosis infection confirmed by stool culture between May 1993 and June 1994. In 41 (91.1%) cases there had been contact with untreated well or mountain water. Y. pseudotuberculosis was also isolated from 4 samples of mountain spring water thought to be the sources of infection. During the course of the illness, acute renal failure (ARF) developed in 6 patients (13.6%). The age distribution of the ARF group (12.3 +/- 1.2 years) was significantly different from the non-ARF group (8.0 +/- 3.2 years). The serogroups of Y. pseudotuberculosis isolates from stool samples were 5 (n = 30) and 4 (n = 15). Isolates from the water samples were all serogroup 5. The main symptoms of both groups were fever, rash, abdominal pain, and vomiting. ARF developed between the 2nd and 14th days (mean 6 days) after the onset of fever, and oliguria (< 400 ml/m2 per day) developed in 3 patients (3/6, 50%) immediately after their fevers had subsided. ARF underwent a benign course, with complete recovery within a maximum of 4 weeks (mean 10.2 days), with 1 exceptional patient requiring hemodialysis. Renal biopsy showed evidence of tubulointerstitial nephritis. Y. pseudotuberculosis should be included as one of the causes of acute interstitial nephritis causing ARF in children, especially when the children have histories of drinking untreated water in endemic areas.

Diagnosis of Yersinia pseudotuberculosis infection by polymerase chain reaction

BACKGROUND

The diagnosis of Yersinia pseudotuberculosis infection is usually based on serologic and/or bacteriologic tests. However, successfully culturing Y. pseudotuberculosis is difficult, and serologic tests in many cases require at least two serial sera obtained during 1-week intervals to confirm rising agglutination antibody titers.

METHODS

We applied a nested polymerase chain reaction method for rapid diagnosis of Y. pseudotuberculosis infection. The DNAs extracted from the peripheral blood and urine of patients and from mountain water, a suspected source of infection, were used as templates for the polymerase chain reaction with consequent amplification of a fragment of the inv gene in the chromosomal DNA of Y. pseudotuberculosis.

RESULTS

The overall rate of diagnosis with the polymerase chain reaction, which was based on a positive result with a single blood sample or one or more positive results with serial samples, was 93.3%. The polymerase chain reaction was also positive in two mountain water samples that were thought to be a source of infection.

CONCLUSION

Based on our results the nested polymerase chain reaction method can be used clinically for rapid and precise diagnosis of Y. pseudotuberculosis infection.

Complement 4 locus II gene deletion and DQA1*0301 gene: genetic risk factors for IgA nephropathy and Henoch-Schönlein nephritis

There have been several reports suggesting that the deficiency of complement 4 (C4) and/or deletion of C4 genes are the genetic risk factors in patients with IgA nephropathy (IgAN) and Henoch-Schönlein nephritis (HSN). In the current study, we tried to clarify the genetic structure of deleted C4 genes as well as the isotype deficiency of the patients. Also, we investigated the DQB and DRB genes which are located near the C4 genes to identify a possible linkage and to find the associated allele. Our results showed that locus II deletion of C4, not the C4B sequence loss, is a risk factor for these diseases and the deleted gene can be either C4A or C4B. There was no specific isotype deficiency or specific allotype which was significantly increased or decreased in the patients. But, there was an increased frequency of DQA1*0301 gene in the patient group (corrected p = 0.04), which suggests that DQA1*0301 as well as C4 gene deletion could be genetic risk factors for these diseases.

Development of monoclonal antibodies against Hantaan virus nucleocapsid protein

Forty-five hybridoma cell lines producing monoclonal antibodies against Hantaan virus, the etiologic agent of hemorrhagic fever with renal syndrome, were generated by fusion of P3-X63-Ag8.V653 myeloma cells with spleen cells of mice immunized with inactivated Hantaan virus vaccine. Among these, 38 antibodies were identified as binding to the 48-kDa nucleocapsid protein by immunoblot assay or radioimmunoprecipitation. Twenty-six of them were of the immunoglobulin G1 (IgG1), nine were of the IgG2a, and three were of the IgA isotype. According to cross-reactivities with other serotypes of the genus Hantavirus, the antibodies were classified into three groups: 6 antibodies specific to the Hantaan serotype (group I), 20 antibodies cross-reacting with Hantaan and Seoul serotypes (SR-11, Tchoupitoulas, and R22) (group II), and 12 antibodies cross-reacting with Hantaan, Seoul, and Prospect Hill serotypes (group III). None of the antibodies cross-reacted with the Puumala serotype. With a panel of antibodies of different cross-reactivities, serotypes of Hantavirus could be differentiated. Thirty-eight monoclonal antibodies against Hantaan virus nucleocapsid protein which have different cross-reactivities between serotypes were developed. These results confirmed the presence of multiple serotype-specific epitopes on the nucleocapsid protein of Hantaan virus, which can be utilized in differentiation of serotypes.

Partial hypoxanthine-guanine phosphoribosyl transferase deficiency in two Korean siblings--a new mutation

Two Korean siblings with partial hypoxanthine-guanine phosphoribosyltransferase (HPRT) deficiency are reported. The index patient was a boy aged 9 years 10 months who developed acute renal failure with a serum uric acid level of 25.9 mg/dl, after vomiting. The younger brother was asymptomatic but had elevated serum uric acid (9.4 mg/dl). The red blood cell HPRT activity of both siblings was one-tenth of normal. Analysis of genomic DNA revealed a point mutation from A (adenine) to G (guanine) at nucleotide position 215 on exon 3; this is a new mutation. The younger brother had the same mutation and the mother was heterozygous for this mutation.

The erythropoietin receptor transmembrane region is necessary for activation by the Friend spleen focus-forming virus gp55 glycoprotein

The erythropoietin receptor (EPO-R), a member of the cytokine receptor superfamily, can be activated by binding either erythropoietin (EPO) or gp55, the Friend spleen focus-forming virus glycoprotein. The highly specific interaction between gp55 and EPO-R triggers cell proliferation and thereby causes the first stage of Friend virus-induced erythroleukemia. We have generated functional chimeric receptors containing regions of the EPO-R and the interleukin-3 receptor (AIC2A polypeptide), a related cytokine receptor which does not interact with gp55. All chimeric receptors were expressed at similar levels, had similar binding affinities for EPO, and conferred EPO-dependent cell growth. Only those chimeric receptors which contained the EPO-R transmembrane region were activated by gp55. These results demonstrate that the transmembrane region of the EPO-R is critical for activation by gp55. In addition, analysis of a soluble, secreted EPO-R and cysteine point mutants of the EPO-R show that the extracytoplasmic region of the EPO-R specifically interacts with gp55.

The cytoplasmic region of the erythropoietin receptor contains nonoverlapping positive and negative growth-regulatory domains

The erythropoietin (EPO) receptor (EPO-R), a member of a large cytokine receptor superfamily, has a 236-amino-acid cytoplasmic region which contains no obvious tyrosine kinase or other catalytic domain. In order to delineate the linear functional domains of the cytoplasmic tail, we generated truncated mutant cDNAs which were transfected into a murine interleukin-3-dependent cell line, Ba/F3, and the EPO-dependent growth characteristics of the stable transfectants were assayed. We identified two unique domains of the cytoplasmic tail. A membrane-proximal positive signal transduction domain of less than or equal to 103 amino acids, in a region highly similar to the interleukin-2 receptor beta chain, was sufficient for EPO-mediated signal transduction. A carboxy-terminal negative-control domain, a serine-rich region of approximately 40 amino acids, increased the EPO requirement for the Ba/F3 transfectants without altering EPO-R cell surface expression, affinity for EPO, receptor oligosaccharide processing, or receptor endocytosis. Truncation of this negative-control domain allowed the Ba/F3 transfectants to grow maximally in only 1 pM EPO, 1/10 the concentration required for growth of cells expressing the wild-type EPO-R. All truncated EPO-R mutants which retained the transmembrane region of the EPO-R polypeptide bound to the gp55 envelope protein of Friend spleen focus-forming virus. Only the functional EPO-R mutants were activated by the gp55, however, suggesting that gp55- and EPO-mediated signaling occur via a similar mechanism.