Effect of initial pH, operating temperature, and dissolved oxygen concentrations on performance of pyrite-fuel cells in the presence of Acidithiobacillus ferrooxidans.

Fuel cell technology can be applied to remove pyrite from pyrite containing mine waste (PCMW) and to generate electricity. This study investigated the effect of pH, presence of Acidithiobacillus ferrooxidans, operating temperature, and dissolved oxygen (DO) concentration on the performance of pyrite-fuel cells (PFCs). These factors affect the pyrite dissolution rate, which affects the electron movement for electricity generation, hence electrical performance. The PFCs performance based on the maximum power density and maximum current density, obtained on the 28th day, was better at pH 2.2 (0.74 mW m-2, 28 mA m-2) than at pH 4.3 and pH 6.5 and in the presence of A. ferrooxidans (i.e., biotic PFCs) than in the abiotic PFCs. The biotic PFCs showed more consistent performance regardless of the operating temperature than the abiotic PFCs. The PFCs performance was better at higher DO concentrations (30-33 mg L-1) than at lower DO concentrations (8-9 and 0-2 mg L-1); however, gas purging used to adjust DO concentrations could adversely affect the biotic PFCs performance. This study demonstrates that PCMW treatment and electricity generation can be achieved using the fuel cell-based technology, and the PFCs performance can be optimized by adjusting the operating conditions.

Applicability of a submersible microbial fuel cell for Cr(VI) detection in water.

Two-chamber microbial fuel cells (MFCs) were used to study the applicability of MFCs for hexavalent chromium (Cr(VI)) detection in water. The microbial acetate oxidation in the anode and the Cr(VI) reduction in the cathode together generated voltages, which were used to indicate the change in Cr(VI) concentrations of the cathode under varying conditions of pH, ionic strength, co-existing Fe(II) concentration, and organic matter concentration. The MFC-based Cr(VI) detector showed a significant change in voltage with increasing Cr(VI) concentration at pH 1 and 2, but not at higher pH conditions. The detector also successfully measured the changes in Cr(VI) concentration at a range of ionic strength (i.e., 10-300 mM), and in the presence of different concentrations of fulvic acid (0-50 mg/L), which was used as a surrogate of organic matters, without interference. The Cr(VI) detection was not interfered by the presence of Fe(II) at the Cr(VI)/Fe(II) ratio of 1:1 and 1:15, but it was interfered at higher ratios (i.e., 1:164 and 1:848). The detector could measure the Cr(VI) concentration from 0.1 to 15 mg/L at pH 2. Overall, the MFC-based Cr(VI) detector may be applied to meet the growing need of real-time Cr(VI) monitoring in water.

Acute Pancreatitis Induced by Quetiapine in an Elderly Patient

Quetiapine is an atypical antipsychotic that is frequently used to manage delirium in geriatric patients. Acute pancreatitis associated with quetiapine has rarely been reported. A 70-year-old male presented with severe abdominal pain a few hours after taking a dose of quetiapine prescribed for delirium. Despite the lack of risk factors of pancreatitis in his medical history, the patient had a slight increase of serum lipase and amylase levels. His general condition improved on discontinuation of quetiapine. A month later, quetiapine was readministered for the recurrence of delirium. Subsequently, the patient developed the same symptom with a significant increase in serum pancreatic enzyme levels, confirming that quetiapine induced the pancreatitis. We reported the first case of quetiapine-induced pancreatitis in Korea, together with a review of the literature.

Tetanus in a Breast Cancer Patient with Adjuvant Chemotherapy

Tetanus is a neurologic disorder caused by a tetanoplasmin which is a neurotoxin elaborated by Clostridium tetani. It is characterized by increased muscle tone and spasm. Since a nationwide childhood vaccination program, tetanus has become a rare disease in Korea. Because many physicians have little experience, misdiagnosis or therapeutic delay may result in unexpected consequences. Although it has high mortality rate on attack, early detection, proper immunization and supportive care can increase survival rate. We report a case of tetanus due to puncture injury by splinter in a 69-year-old woman who has been treated with adjuvant chemotherapy of breast cancer. She was admitted to emergency room with difficulty of opening mouth for 3 days. After two days, we detected that the patient suddenly fell on her back with muscle spasm, so we diagnosed her with tetanus. She was given human tetanus immunoglobulin intramuscularly and supportive care. Forty days after admission, she was discharged without complications.

A Case of Henoch-Shonlein Purpura Caused by Rifampin / 결핵및호흡기질환

Rifampin is one of the first line drugs for treating tuberculosis, but it might be associated with serious adverse effects, including renal failure. We report here on a case of a 57-year-old patient who developed Henoch-Shonlein purpura during antituberculosis therapy that included rifampin. The patient converted to negative on the AFB smear for tuberculosis two weeks after the initial administration of antituberculosis medication. After treatment for 60 days, this patient was diagnosed with Henoch-Shonlein purpura by the purpura lesion on the lower legs, the leukocytoclastic vasculitis, the renal impairment and the pathological examination. After stopping rifampin, the skin lesions disappeared in about 10 days and his renal function gradually improved. This case study showed that Henoch-Schonlein purpura can be caused by rifampin during antituberculosis therapy and we recommend that the use of rifampin should be restrained when clinical symptoms of Henoch-Shonlein purpura are observed.

Staged Reimplantation Using Cement Spacer Containing Antibiotics in Infected Total Knee Arthroplasty / 대한정형외과학회잡지

Despite the continually improving results of total knee arthroplasty, infection remains the most debilitating complication. The treatments of infected total knee arthroplasty were variable, but initially we removed infected implants and inserted antibiotic containing cemented spacer. Postoperatively, patients were mobilized in a 30 knee flexion state and treated with parenteral antibiotics. After control of infection was clinically and radiologically determined, we inserted PCL substitute total knee prosthesis. Five days postoperatively, patient began touch down standing exercise. We observed two cases in whom infected total knee arthroplasty had been salvaged successfully with two-stage implantation using cement spacers containing antibiotics.