The klotho gene was originally identified as a putative age-suppressing gene in mice that extends life span when overexpressed. It induces complex phenotypes resembling human premature aging syndromes when disrupted. The gene was named after a Greek goddess Klotho who spun the thread of life. Since then, various functional aspects of the klotho gene have been investigated, leading to the identification of multiple novel endocrine axes that regulate various metabolic processes and an unexpected link between mineral metabolism and aging. The purposes of this review were to overview recent progress on Klotho research and to discuss a novel aging mechanism.

The number of patients with end-stage renal disease (ESRD) is rising very rapidly as the number of elderly and patients with diabetes increases in Korea. ESRD Registry Committee of the Korean Society of Nephrology (KSN) collected dialysis therapy data in Korea through an online registry program on the KSN website. The status of renal replacement therapy in Korea at the end of 2009 was as follows. First, total number of patients with ESRD was 56,396 (hemodialysis [HD], 37,391; peritoneal dialysis [PD], 7,618; functioning kidney transplant [KT], 11,387). The prevalence of ESRD was 1,113.6 patients per million population (PMP). Proportion of patients undergoing renal replacement therapy was 66.3% with HD, 13.5% with PD, and 20.2% with KT. Second, a total of 8,906 (HD, 6,540; PD, 1,125; KT, 1,241; incidence rate of 175.9 PMP) patients developed ESRD in 2009. Third, the most common primary causes of ESRD were diabetic nephropathy (45.4%), hypertensive nephrosclerosis (18.3%), and chronic glomerulonephritis (11.1%). Fourth, mean urea reduction rate was 67.5% and 73.8% in male and female patients, respectively, undergoing HD. Mean Kt/V was 1.38 in male patients and 1.65 in female patients. Fifth, the overall 5-year survival rate of male patients undergoing dialysis was 65.4% and that of female patients was 67.4%.

Background/Aims: We made a systematic review and evaluation of endoscopic cryotherapy of endobronchial tumors, investigating safety and efficacy. Methods: Qualified studies regarding endoscopic cryotherapy of lung tumors were systemically evaluated using available databases according to predefined criteria. Results: In total, 16 publications were included in the final assessment. A narrative synthesis was performed because a formal meta-analysis was not viable due to the lack of controlled studies and study heterogeneity. Overall success rates for significant recanalization of the obstruction were approximately 80%, although they varied, depending on disease status in the patient population. Complications from the procedure developed in 0-11.1% of cases, most of which were minor and controlled by conservative management. Although limited data were available on comprehensive functional assessment, some studies showed that respiratory symptoms, pulmonary function tests, and performance status were significantly improved. Conclusions: Endoscopic cryotherapy was found to be a safe and useful procedure in the management of endobronchial tumors although its efficacy and appropriate indications have yet to be determined in well-designed controlled studies.

Background/Aims: Impaired responsiveness to clopidogrel is common in patients with type 2 diabetes mellitus (DM). The aim of this study was to evaluate the clinical application of a point-of-care assay to detect impaired responsiveness to clopidogrel after coronary stent implantation in patients with type 2 DM. Methods: We measured P2Y12 reaction units (PRU) with the VerifyNow point-of-care assay in 544 consecutive patients undergoing dual or triple (i.e., dual plus cilostazol) anti-platelet therapy after coronary stent implantation. High platelet reactivity (HPR) was defined as a PRU value ${\geq}$ 240. Results: The mean PRU values were $233.5\;{\pm}\;83.2\;and\;190.3\;{\pm}\;85.5$ in patients undergoing dual or triple anti-platelet therapy, respectively (p < 0.001). Patients with DM manifested higher post treatment PRU values ($238.3\;{\pm}\;82.4\;vs.\;210.8\;{\pm}\;86.8$, p = 0.001) and a higher frequency of HPR (44.8% vs. 31.0%, p = 0.003) as compared to patients without DM. We also found that higher PRU values and a higher frequency of HPR were present in patients with DM who were undergoing both triple and dual anti-platelet therapy. However, the higher post-treatment PRU values observed in patients with DM decreased with triple anti-platelet therapy ($219.4\;{\pm}\;82.5\;vs.\;247.9\;{\pm}\;81.1$, p = 0.044). Conclusions: A point-of-care assay can detect elevated platelet reactivity and impaired responsiveness to clopidogrel in patients with type 2 DM. The addition of cilostazol to dual anti-platelet therapy may decrease post-treatment PRU values in patients with type 2 DM.

Background/Aims: To compare the effect of levofloxacin and moxifloxacin on treatment outcomes among patients with multidrug-resistant tuberculosis (MDR-TB). Methods: A retrospective analysis of 171 patients with MDR-TB receiving either levofloxacin or moxifloxacin was performed. Treatment responses were categorized into treatment success (cured and treatment completed) or adverse treatment outcome (death, failure, and relapsed). Results: The median age of the patients was 42.0 years. Approximately 56% of the patients were male. Seventeen patients had extensively drug-resistant tuberculosis, and 20 had a surgical resection. A total of 123 patients (71.9%) received levofloxacin for a median 594 days, and 48 patients (28.1%) received moxifloxacin for a median 673 days. Other baseline demographic, clinical, and radiographic characteristics were similar between the two groups. The moxifloxacin group had a significantly higher number of resistant drugs (p < 0.001) and a higher incidence of resistance to ofloxacin (p = 0.005) in the drug sensitivity test. The treatment success rate was 78.9% in the levofloxacin group and 83.3% in the moxifloxacin group (p = 0.42). Adverse reactions occurred at similar rates in the groups (p = 0.44). Patients in the moxifloxacin group were not more likely to have treatment success than those in the levofloxacin group (adjusted odds ratio, 0.76; 95% confidence interval, 0.24 to 2.43; p = 0.65). Conclusions: Both levofloxacin and moxifloxacin showed equivalent efficacy for treating MDR-TB.

Background/Aims: Pandemic influenza A (H1N1) virus infection presents with variable severity. However, little is known about clinical predictors of disease severity. We studied the clinical predictors of severe pandemic H1N1 pneumonia and their correlation with radiological findings. Methods: We reviewed medical and radiological records of adults with pandemic H1N1 pneumonia. After classification of patients into severe and non-severe groups, the following data were evaluated: demographic data, pneumonia severity index (PSI), CURB65, risk factors, time to first dose of antiviral medication, routine laboratory data, clinical outcome, and radiological characteristics. Results: Of 37 patients with pandemic H1N1 pneumonia, 12 and 25 were assigned to the severe and non-severe groups, respectively. PSI score, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dyhydrogenase (LDH) levels were higher in the severe group than in the non-severe group (p = 0.035, 0.0003, 0.0023, and 0.0002, respectively). AST, ALT, and LDH levels were positively correlated with the radiological findings (p < 0.0001, 0.0003, and < 0.0001, respectively) and with the number of involved lobes (p = 0.663, 0.0134, and 0.0019, respectively). The most common finding on high resolution computed tomography (HRCT) scans was ground-glass attenuation with consolidation (n = 22, 60%), which had a predominantly patchy distribution (n = 31). Conclusions: We demonstrated a positive correlation between clinical findings, such as serum AST, ALT, and LDH levels, and radiological findings. A combination of clinical and HRCT indicators would be useful in predicting the clinical outcome of pandemic H1N1 pneumonia.

Background/Aims: Increased osteoclast activity is a pivotal finding in osteoporosis. This increase is mediated via the mevalonate-to-cholesterol pathway, which is involved in producing the intermediates required for osteoclast activity. D-003, a mixture of high molecular weight sugarcane wax acids, has been shown to inhibit cholesterol synthesis prior to mevalonate production, resulting in a reduction of bone loss and resorption in ovariectomized rats. Moreover, previous studies have demonstrated that short-term D-003 treatment reduces urinary excretion of deoxypyridinoline/creatinine in postmenopausal women. Methods: We performed a double-blinded, placebo-controlled study to investigate the effects of D-003 (10 mg/day) treatment for 3 years on bone mineral density (BMD) in 83 postmenopausal women with low BMD. Results: Over 3 years, D-003 treatment increased lumbar spine BMD (5.1%, p < 0.01) and improved osteoporosis-related quality of life scores as compared with placebo-treated controls. D-003 was also well tolerated; the frequency of adverse events in the bone, joints, or muscle with D-003 treatment (p < 0.05) was lower than in the placebo group. Conclusions: D-003 treatment (10 mg/day) for 3 years increased lumbar spine BMD and produced clinical improvements in postmenopausal women with low BMD. Further studies, however, will be required to confirm these results.

Background/Aims: Graves' disease (GD) is caused by thyroid-stimulating hormone receptor (TSHR) and thyroid-stimulating immunoglobulin (TSI). We used a recently introduced, technically enhanced TSI bioassay to assess its diagnostic value and determine the cut-off in patients in high iodine intake area. Methods: In a cross-sectional setting, we collected serum from 67 patients with untreated GD, 130 with GD under treatment, 22 with GD in remission, 42 with Hashimoto's thyroiditis, 12 with subacute thyroiditis, 20 with postpartum thyroiditis, and 93 euthyroid controls. TSI was measured using the $Thyretain^{TM}$ bioassay, which is based on Chinese hamster ovary cells transfected with chimeric TSHR (Mc4). TSI levels are reported as a specimen-to-reference ratio percentage (SRR%). Results: The TSI levels in patients with GD (either treated or not) were significantly higher than those of the remaining patients (p < 0.05). The new bioassay showed a sensitivity of 97.0% and a specificity of 95.9% with a cut-off value of 123.0 SRR% for GD. A weak correlation was found between TSI and thyrotropin-binding inhibiting immunoglobulin (TBII) ($r_s$ = 0.259, p = 0.03), but no correlation was found between TSI and tri-iodothyronine or free thyroxine. Conclusions: The Mc4-CHO bioassay showed comparable diagnostic value for GD with the conventional TBII assay. We propose a cut-off of 123.0 SRR% in areas where iodine intake is high.

Background/Aims: For unknown reasons, caspase-1 -/- mice, protected against cisplatin-induced acute renal failure (ARF), are deficient in interleukin (IL)-$1{\alpha}$. We thus asked whether IL-$1{\alpha}$ deficiency underlies the mechanism of protection against cisplatin-induced ARF in these mice. Methods: Cisplatin (30 mg/kg) was injected intraperitoneally into wild-type C57BL/6 mice to produce a cisplatin-induced model of ARF. IL-$1{\alpha}$ was measured in control vehicle- and cisplatin-treated wild-type animals. We also examined whether IL-$1{\alpha}$ -/- mice were similarly protected against cisplatin-induced ARF. Additionally, infiltration of CD11b- and CD49b-positive cells, as markers of macrophages, natural killer, and natural killer T cells (pan-NK cells), was investigated in wild-type and IL-$1{\alpha}$ -/- mice. Results: Compared with vehicle-treated mice, renal IL-$1{\alpha}$ increased in cisplatin-treated wild-type mice beginning on day 1. IL-$1{\alpha}$ -/- mice were shown to be protected against cisplatin-induced ARF. No significant difference in the infiltration of neutrophils or CD11b- and CD49b-positive cells were observed between wild-type and IL-$1{\alpha}$ -/- mice. Conclusions: Mice deficient in IL-$1{\alpha}$ are protected against cisplatin-induced ARF. The lack of IL-$1{\alpha}$ may explain, at least in part, the protection against cisplatin-induced ARF observed in caspase-1 -/- mice. Investigation of the protective mechanism (s) in IL-$1{\alpha}$ -/- mice in cisplatin-induced ARF merits further study.

Background/Aims: The purpose of this study was to evaluate the value of initial Creactive protein (CRP) as a predictor of clinical outcome and to investigate whether follow-up CRP measurement is useful for the prediction of the clinical outcome of bloodstream infections in patients with liver cirrhosis (LC), whose CRP production in response to infection may be attenuated. Methods: A retrospective, observational study including 202 LC patients with Escherichia coli or Klebsiella pneumoniae bacteremia was conducted to assess the usefulness of serial CRP measurements in predicting clinical outcome in LC patients. The CRP ratio was defined as the ratio of the follow-up CRP level to the initial CRP level. Results: The overall 30-day mortality rate of the study population was 23.8% (48/202). In the multivariate analysis, advanced age (${\geq}$ 70 years), healthcare-associated or nosocomial infections, model for end-stage liver disease (MELD) score of ${\geq}$ 30, and initial body temperature of < $37^{\circ}C$ were significant factors associated with mortality (all p < 0.05). No association between initial CRP level and mortality was found. In a further analysis including 87 evaluable cases who had repeated CRP measurements at day 4 and/or 5, a CRP ratio of ${\geq}$ 0.7 was found to be a significant factor associated with mortality (odds ratio, 19.12; 95% confidence interval, 1.32 to 276.86; p = 0.043) after adjusting for other confounding variables. Conclusions: Initial CRP level did not predict mortality of sepsis in LC patients. However, serial CRP measurements during the first week of antimicrobial therapy may be useful as a prognostic factor for mortality in LC patients.

The role of radiotherapy in the treatment of hepatocellular carcinoma (HCC) has been limited to date, because the liver has a low tolerance to radiation. However, reconstructing tumors and surrounding organs via a three-dimensional conformal planning system can avoid excess radiotherapy exposure to the rest of the liver and adjacent organs. Recently, the concept of "adaptive radiotherapy," such as with helical tomotherapy, has been introduced for treating HCC. Helical tomotherapy obtains an image from the computed tomography component, which allows targeted regions to be visualized prior to, during, and immediately after each treatment and delivers intensity-modulated radiation therapy. We report two patients with advanced HCC who underwent tomotherapy treatment. One was a patient afflicted with advanced HCC and a portal vein tumor thrombus, which was treated with tomotherapy combined with transarterial chemolipiodolization. The other was a patient afflicted with multiple pulmonary metastases treated with tomotherapy followed by systemic chemotherapy.

Cutaneous metastases originating from an internal cancer are relatively uncommon in clinical practice, and metastatic lesions to the breast are rarer than those to the skin. Skin metastases of lung cancer, which may be the first sign of the disease, usually indicate progressive disease and a poor prognosis. We describe a 47-year-old male who presented with recurring masses in the lumbar region bilaterally and the right breast. Immunohistochemical findings and radiological imaging suggested lung cancer. This is the first reported case of small cell lung cancer metastasizing to two separate, uncommon sites, the skin and breast.

We report a case of a 59-year-old man with testicular germ cell tumor who showed new hypermetabolic lesions at the left axillary lymph nodes on a post-treatment positron emission tomography-computed tomography (PET-CT) scan. The hypermetabolic lesions were found to be caused by an influenza vaccination 10 days prior to the PET-CT scan and disappeared without additional treatment. To date, he is alive with complete remission.

Anti-Ro autoantibody is associated with Sj${\ddot{o}}$gren's syndrome (SS), systemic lupus erythematosus (SLE), and neonatal lupus syndrome (i.e., congenital complete heart block in newborns). Generally, the adult atrioventricular (AV) node is believed to be relatively resistant to the scarring effects of anti-Ro/anti-La autoantibodies. However, there have been some reports of adult complete AV block in SS and SLE patients. Here, we report a case of complete heart block in primary SS with anti-Ro autoantibodies, with no other risk factor for the development of heart block, and review their etiological association.

Neutrophils play an important role in immunological function. Neutropenic patients are vulnerable to infection, and except fever is present, inflammatory reactions are scarce in many cases. Additionally, because infections can worsen rapidly, early evaluation and treatments are especially important in febrile neutropenic patients. In cases in which febrile neutropenia is anticipated due to anticancer chemotherapy, antibiotic prophylaxis can be used, based on the risk of infection. Antifungal prophylaxis may also be considered if long-term neutropenia or mucosal damage is expected. When fever is observed in patients suspected to have neutropenia, an adequate physical examination and blood and sputum cultures should be performed. Initial antibiotics should be chosen by considering the risk of complications following the infection; if the risk is low, oral antibiotics can be used. For initial intravenous antibiotics, monotherapy with a broad-spectrum antibiotic or combination therapy with two antibiotics is recommended. At 3-5 days after beginning the initial antibiotic therapy, the condition of the patient is assessed again to determine whether the fever has subsided or symptoms have worsened. If the patient's condition has improved, intravenous antibiotics can be replaced with oral antibiotics; if the condition has deteriorated, a change of antibiotics or addition of antifungal agents should be considered. If the causative microorganism is identified, initial antimicrobial or antifungal agents should be changed accordingly. When the cause is not detected, the initial agents should continue to be used until the neutrophil count recovers.