Evaluating Carriers for Immobilizing Saccharomyces cerevisiae for Ethanol Production in a Continuous Column Reactor

We evaluated a more practical and cost-effective immobilization carriers for ethanol production using the yeast Saccharomyces cerevisiae. Three candidate materials-rice hull, rice straw, and sawdust-were tested for their cell-adsorption capacity and operational durability. Derivatizations of rice hull, rice straw, and sawdust with the optimal concentration of 0.5 M of 2-(diethylamino)ethyl chloride hydrochloride (DEAE . HCl) resulted in > 95% adsorption of the initial yeast cells at 2 hr for DEAE-rice hull and DEAE-sawdust and in only approximately 80% adsorption for DEAE-rice straw. In addition, DEAE-sawdust was found to be a more practical carrier for immobilizing yeast cells in terms of operational durability in shaking flask cultures with two different speeds of 60 and 150 rpm. Furthermore, the biosorption isotherms of DEAE-rice hull, -rice straw, and -sawdust for yeast cells revealed that the Qmax of DEAE-sawdust (82.6 mg/g) was greater than that of DEAE-rice hull and DEAE-rice straw. During the 404-hr of continuous column reactor operation using yeast cells immobilized on DEAE-sawdust, no serious detachment of the yeast cells from the DEAE-sawdust was recorded. Ethanol yield of approximately 3.04 g/L was produced steadily, and glucose was completely converted to ethanol at a yield of 0.375 g-ethanol/g-glucose (73.4% of the theoretical value). Thus, sawdust is a promising practical immobilization carrier for ethanol production, with significance in the production of bioethanol as a biofuel.

Ethanol Production from Glycerol by the Yeast Pachysolen tannophilus Immobilized on Celite during Repeated-Batch Flask Culture

We investigated a novel process for production of ethanol from glycerol using the yeast Pachysolen tannophilus. After optimization of the fermentation medium, repeated-batch flask culture was performed over a period of 378 hr using yeast cells immobilized on Celite. Our results indicated that the use of Celite for immobilization of P. tannophilus was a practical approach for ethanol production from glycerol, and should be suitable for industrial ethanol production.

Combined Therapy of Cyclophosphamide and Steroid on Progressive IgA Nephropathy / 대한신장학회지

PURPOSE: There were several reports showing that combined therapy of steroid and cyclophosphamide (PSL+CPA) was effective on progressive IgA nephropathy, but it remains inconclusive. METHODS: Patients with IgA nephropathy who showed more than 1.5 mg/dL of serum creatinine (SCr) and proteinuria and who were treated with the combined therapy in the Kyung hee University Hospital. RESULTS: The subjects were fifteen patients whose age was 40.3+/-10.8 yr, and the follow-up period was 39.1+/-24.6 months. Proteinuria levels declined from 4.08+/-2.58 g/gCr baseline to 1.80+/-1.72 g/ gCr 6 months after the treatment (p<0.0001). The comparison between the levels before & 6 months after the delta eGFR showed the improvement from -1.16+/-6.29 mL/min/1.73m2/month to 0.84+/-1.63 mL/ min/1.73m2/month (p=0.21), while these differences did not reach the level of statistical significance. According to delta eGFR, when the subjects were divided into the responder group (8 patients) and the non-responder group (7 patients), the former was 1.69+/-1.88 mL/min/1.73m2/month and the latter was -0.14+/-0.15 mL/min/1.73m2/month with significant difference (p=0.0014). According to UPCR, the responder group (12 patients) and the non-responder group (3 patients), systolic pressure, glomerulosclerosis and proteinuria after 6 months were significantly different (p=0.0115). Also, according to progressing ESRD, the CKD group (7 patients) and ESRD group (8 patients), age and SCr have shown a significant difference (p=0.0064). CONCLUSION: The combined therapy on progressive IgA nephropathy effectively reduced proteinuria and had protective effects on renal function in some patients. However, proteinuria and others were insufficient to be predictive factors on therapeutic responses. Large-scale prospective controlled studies may be necessary in the future.

Improved Bioethanol Production Using Activated Carbon-treated Acid Hydrolysate from Corn Hull in Pachysolen tannophilus

To optimally convert corn hull, a byproduct from corn processing, into bioethanol using Pachysolen tannophlius, we investigated the optimal conditions for hydrolysis and removal of toxic substances in the hydrolysate via activated carbon treatment as well as the effects of this detoxification process on the kinetic parameters of bioethanol production. Maximum monosaccharide concentrations were obtained in hydrolysates in which 20 g of corn hull was hydrolyzed in 4% (v/v) H2SO4. Activated carbon treatment removed 92.3% of phenolic compounds from the hydrolysate. When untreated hydrolysate was used, the monosaccharides were not completely consumed, even at 480 h of culture. When activated carbon-treated hydrolysate was used, the monosaccharides were mostly consumed at 192 h of culture. In particular, when activated carbon-treated hydrolysate was used, bioethanol productivity (P) and specific bioethanol production rate (Qp) were 2.4 times and 3.4 times greater, respectively, compared to untreated hydrolysate. This was due to sustained bioethanol production during the period of xylose/arabinose utilization, which occurred only when activated carbon-treated hydrolysate was used.

Retrospective Comparisons about Effects of Angiotensin II Receptor Blocker and/or Steroid on Proteinuria Reduction and Renal Protection in IgA Nephropathy Patients with Proteinuria less than 1 g/g / 대한신장학회지

PURPOSE: It remains controversial how to treat the IgA nephropathy (IgAN) patients with proteinuria <1g/day. We investigated effects of single or combined use of angiotensin II receptor blocker (ARB) and steroid on proteinuria reduction and renal protection in IgAN patients with normal renal function and urine protein/creatinine ratio (PCR) < or =1 g/g. METHODS: Oral prednisolone was given at an initial dose of 1 mg/kg every day for 2 months and then gradually tapered for 4 months. An ARB irbesartan or losartan or valsartan was given until the end of follow-up. RESULTS: Over a mean follow-up period of about 40 mo, the urine PCR decreased from 0.64+/-0.29 g/g to 0.32+/-0.31 g/g in the combination group (n=26) (p<0.05). But in ARB (n=17) and steroid groups (n=20), it decreased from 0.56+/-0.26 g/g to 0.54+/-0.45 g/g and from 0.50+/-0.26 g/g to 0.34+/-0.32 g/g, respectively, while there were no statistical significances. Serum creatinine decreased from 0.83+/-0.13 mg/dL to 0.73+/-0.14 mg/dL in steroid group (p<0.01), and from 0.92+/-0.17 mg/dL to 0.81+/-0.23 mg/dL in combination group (p<0.01). But in ARB group, no statistical significance was noticed. All patients achieved the BP goal < or =130/80 mmHg by adding anti-hypertensive drugs, if necessary. CONCLUSION: Our results indicate that (steroid or) combination therapy reduced proteinuria and improved renal function in the patients with proteinuria < or =1 g/g. Further prospective controlled studies are required to clarify the effect of steroid over the long term.

The Effect of Conversion from Cyclosporine to Tacrolimus in Renal Allograft Recipient with Hyperlipidemia / 대한신장학회지

PURPOSE: Management of cardiovascular risk factors is of major importance in renal transplant recipients to determine long-term outcomes. While calcineurin inhibitors improve the clinical course after kidney transplantation, they have been implicated in contributing to increased cardiovascular risk. This study investigated the influence of conversion from cyclosporine to tacrolimus on cardiovascular risks and graft function in renal allograft recipients with hyperlipidemia. METHODS: Twenty three adult renal recipients who were receiving cyclosporine-based regimen for more than one year after transplantation and had hyperlipidemia (serum total cholesterol > or =200 mg/dL) were enrolled. The effect of conversion from cyclosporine to tacrolimus was evaluated with blood pressure, fasting lipid profile, glucose and HbA1c. They were measured at baseline and at 1, 3, 6 and 12 months after conversion. The change in estimated glomerular filtration rate (eGRF) was also compared between before and after conversion. RESULTS: Though conversion from cyclosporine to tacrolimus did not cause significant differences in the serum triglyceride level, there was a noticeable decline in total cholesterol level (213.78+/-16.28 to 185.96+/-38.62 mg/dL, p<0.01). Conversion did not trigger new onset or worsening of diabetes mellitus with no meaningful differences in fasting blood glucose and HbA1c levels. The eGFR stabilized with Tacrolimus in comparison with the cyclosporine (-2.9+/-13.4 mL/min vs. -7.3+/-13.8 mL/min). CONCLUSION: Conversion to tacrolimus would be preferable to cyclosporine for maintenance immunesuppression in renal recipient with hyperlipidemia, as it meliorates hyperlipidemia and leads to stabilization of allograft function.

Furfural from Pine Needle Extract Inhibits the Growth of a Plant Pathogenic Fungus, Alternaria mali

The antifungal effect of pine needle extract prepared by a distinguishable extraction method and the dry distillation method, was examined. The effect of this extract itself was insignificant. The chemical components of pine needle extract were then investigated by gas chromatographic analysis, and four chemical components, acetol, furfural, 5-methyl furfural, and terpine-4-ol, were identified. The antifungal effects of those four chemical components against Alternaria mali (A. mali), an agent of Alternaria blotch of apple, were then examined. It was observed that the minimum inhibitory concentrations (MICs) were 6.25, 0.78, 0.78, and 12.5 (mg/ml) of acetol, furfural, 5-methyl furfural, and terpine-4-ol, respectively. MICs of furfural and 5-methyl furfural had the same order of magnitude as that of an antifungal agrochemical, chlorothalonil. Although furfural itself can not be completely substituted for an antifungal agrochemical, a partial mixture of furfural and antifungal agrochemical may be used as a substitute. The use of agrochemicals for the prevention of plant disease caused by pathogenic fungus such as A. mali could be partially reduced by the application of this mixture.

Glucose Pump Technique is as Good as Ultrasound Dilution Technique for Vascular Access Surveillance in Hemodialysis Patients / 대한신장학회지

PURPOSE: Vascular access flow (Qa) measurements are important in the surveillance protocol of hemodialysis vascular access stenosis. The glucose pump technique (GPT) is a technique for Qa measurement based on the dilution technique of a constant glucose infusion that was introduced in 1995. The aim of this study is to verify the clinical efficacy of GPT in vascular access surveillance compared with ultrasound dilution technique. METHODS: In 31 chronic hemodialysis patients with a AV fistula, we compared Qa measurements performed with GPT in pre-dialysis and the ultrasound dilution technique (Transonic HD01, Transonic System Inc., Ithaca, NY) during hemodialysis. RESULTS: Mean Qa was 1171 ml/min by GPT versus 1028 ml/min by HD01 (p=0.262). There was a strong linear correlation between the two methods (r=0.61; p<0.01). Ultrasound dilution technique HD01 yielded 6 cases of high risk Qa measurements and GPT yielded 4 cases of high risk Qa measurements. The diagnostic accuracy of GPT tested with the ROC curve was similar with ultrasound dilution technique HD01. The specificity and sensitivity was 80% and 66.7% according to Qa=600 ml/min. But sensitivity was 83.3% according to Qa=750 ml/min. CONCLUSION: GPT offers the advantage of a simple and economic bedside procedure easily performed before dialysis and had a similar diagnostic accuracy and efficiency compared with ultrasound dilution technique HD01.

Dialysis in a Patient with Hemophilia / 대한신장학회잡지

Hemophilia is a rare inherited bleeding disorder. The most common manifestation of hemophilia is hemorrage and it can occur at any site of the body. Chronic renal failure results from a variety of systemic disorders and its incidence is now increasing. Until now, chronic renal failure in hemophilia was rare and there was no reported case of hemodialysis or peritoneal dialysis in hemophilia patient in korea. The modality of dialysis for hemophiliac end stage renal patients is a difficult choice because hemophiliac patients always have the risk of bleeding. We have experienced one case of end stage renal disease developed in a patient with hemophilia A. He first got continuous ambulatory peritoneal dialysis for 2 years and then switched to hemodialysis because of recurrent peritoneal infection. While getting peritoneal dialysis, there was no intraperitoneal or retroperitoneal hemorrhage episode. Now he gets hemodialysis through Perm catheter. During hemodialysis, he has no bleeding complication without any factor VIII supplement.

A Case of Metformin-associated Lactic Acidosis / 대한신장학회잡지

A 76-year-old female admitted with nausea, anorexia, vague abdominal pain, and malaise. Her past medical history included an 15-year history of type 2 diabetes mellitus and hypertension. She had been taking metformin, glipizid, and amlodipine for past 2 years. One week previously, she underwent gastroscopy to evaluate epigastic pain, and she was diagnosed Helicobacter pylori positive duodenal ulcer, for which she was treated with amoxicillin, clarithromycin, and omeprazole. At admission, laboratory test revealed lactic acidosis (pH 7.23, bicarbonate 8.3 mEq/L, and lactate 5.51 mmol/L) and acute renal failure with a serum creatinine of 7.4 mg/dL. We diagnosed meformin-associated lactic acidosis and the patient made a complete recovery following therapy with bicarbonate-based hemodialysis and supportive care. It is the first report of metformin-associated lactic acidosis in Korea.

Paradoxical effects of elastase inhibitor guamerin on the tissue repair of two different wound models: sealed cut and exposed tongue wounds

Innate elastase inhibitors are known to be putatively involved in the regulation of tissue inflammation by inhibiting polymorphonuclear leukocyte (PMN) derived proteinases. The aim of this study was to evaluate affects of leukocyte elastase suppression and PMN infiltration on wound healing in mouse by administering the recombinant elastase inhibitor guamerin (rEIG) in two different wound models; 1) impaired pin-punctured dorsal mucosa of anterior tongue wound, 60 mice, treated with saline containing rEIG that were fed ad libitum and 2) stable linear excisional cutaneous wound, 40 mice, covered with fibrin sealant containing rEIG. The progress of healing was analyzed by histological methods. The tongue wounds treated with rEIG became edematous around the pin-punctured tongue wound, and influx of inflammatory cells and PMN into the underlying stromal tissue were seen rapidly after wounding and peaked between 2-4 days. Whereas the control mice showed almost no wheal formation in the pin-punctured wound, a far lesser levels of PMN infiltration, and almost complete wound closure in 4 days. In the other model, the liner excisional cutaneous wound treated with fibrin sealant containing rEIG showed early wound constriction, lesser degree of inflammatory cells influx, and complete reepithelialization in 4-5 days, whereas the wound of control mice with the fibrin sealant alone showed contrary delayed reepithelialization, greater degree of inflammatory cell infiltration, and consequencial formation of greater granulation tissue at wound site. Taken together, these data suggest paradoxical effects of rEIG on the wound healing where in the wound exposed to infiltrating milieu of microorganisms in the oral cavity, the rEIG aggravates the wound healing by interfering with other innate defensive factors and extended greater flux of PMNs to inflamed wound site, while in the wound enclosed by fibrin, the rEIG accelerated wound healing by inhibiting the inflammation-generated proteases and the acute inflammatory reaction.