[Show abstract][Hide abstract] ABSTRACT: Skeletal muscle is a major target of thyroid hormone action. Although sarcopenia is associated with adverse health outcomes in the elderly, few studies have examined the association between sarcopenia and thyroid hormone levels in elderly Asians. We investigated the relationship between thyroid hormone levels and sarcopenia in elderly Koreans.
[Show abstract][Hide abstract] ABSTRACT: Antipsychotics are the drug of choice for patients with schizophrenia, but they can induce hyperprolactinemia and growth of pituitary adenomas by blocking dopamine 2 receptors in the pituitary gland. In contrast, the medical treatment for a prolactinoma is a dopamine agonist. Therefore, managing a patient concurrently diagnosed with a prolactinoma and psychosis is challenging. We describe a patient with schizophrenia who was diagnosed with a prolactinoma. We changed his neuroleptic to quetiapine and prescribed bromocriptine for the prolactinoma. As a result, the patient was successfully treated with a dopamine agonist and antipsychotic without psychotic exacerbation. Our case suggests that dopamine agonists can be administrated to patients with schizophrenia and a prolactinoma without adversely affecting their psychopathological status.
[Show abstract][Hide abstract] ABSTRACT: Silica nephropathy occurs after chronic heavy exposure to silica, resulting in the development of chronic kidney disease and progression to end-stage renal disease. However, acute kidney injury due to silica exposure is rare and its renal pathology remains unclear. Here, we report a case of acute sodium silica poisoning presenting as acute kidney injury.
A 42-year-old man ingested a fertilizer containing sodium silicate. His serum creatinine increased by 5.06 mg/dL from 1.1 mg/dL 2 days after silicate ingestion. Owing to the decline in kidney function despite fluid therapy, a kidney biopsy was performed. The kidney showed acute tubular necrosis without infiltration of inflammatory cells. On day 5 of admission, hemodialysis was initiated to treat the hyperkalemia and oliguria, and treatment with methylprednisolone was initiated for the acute lung injury. The patient was administered 1 mg/kg of methylprednisolone intravenously daily for 2 weeks, followed by a 2-week taper. Hemodialysis was discontinued on day 10 and the patient's renal function recovered completely. However, he died on day 40 of hospitalization owing to complicated lung fibrosis and persistent pneumothorax/pneumomediastinum.
[Show abstract][Hide abstract] ABSTRACT: Background
Recent studies have shown that men with diabetes have lower testosterone levels than healthy men. However, studies on the correlation between testosterone and diabetes are rare in Korea. We examined the relationship between testosterone deficiency and markers related to diabetes in adult Korean men.
A total 464 men with diabetes who visited an outpatient clinic at Ajou University Hospital and had serum total testosterone and serum insulin levels measured between January 2000 and September 2013 were selected. Blood samples were collected after the subjects had fasted overnight. We divided the participants into testosterone deficient and normal groups. Testosterone deficiency was defined as having a serum total testosterone level <3.5 ng/mL.
Of 464 subjects, 34.9% had a testosterone deficiency. The mean levels of fasting plasma glucose (P=0.007) and glycated hemoglobin (HbA1c; P=0.038) were significantly higher in the testosterone deficiency group than in the normal group. To clarify the relationship between serum total testosterone level and fasting plasma glucose or HbA1c values, Pearson's correlation test was performed. Fasting plasma glucose levels (r=-0.142, P=0.002) and HbA1c values (r=-0.097, P=0.040) showed a significant negative correlation with serum testosterone levels in men with diabetes.
Major markers of diabetes that are associated with testosterone deficiency are fasting plasma glucose and HbA1c values. Poor glycemic control appears to be associated with testosterone deficiency in Korean men with diabetes.
[Show abstract][Hide abstract] ABSTRACT: Due to the increasing concerns about limited fossil resources and environmental problems, there has been much interest in
developing biofuels from renewable biomass. Ethanol is currently used as a major biofuel, as it can be easily produced by
existing fermentation technology, but it is not the best biofuel due to its low energy density, high vapor pressure, hygroscopy,
and incompatibility with current infrastructure. Higher alcohols, including 1-propanol, 1-butanol, isobutanol, 2-methyl-1-butanol,
and 3-methyl-1-butanol, which possess fuel properties more similar to those of petroleum-based fuel, have attracted particular
interest as alternatives to ethanol. Since microorganisms isolated from nature do not allow production of these alcohols at
high enough efficiencies, metabolic engineering has been employed to enhance their production. Here, we review recent advances
in metabolic engineering of microorganisms for the production of higher alcohols.
[Show abstract][Hide abstract] ABSTRACT: Colonoscopic examination is a safe procedure, however, unexpected complications can sometimes occur. Bleeding and perforation of the colon have been reported as the most common complications. Hemoperitoneum after colonoscopy is an unusual complication, but it may be catastrophic. We report on a 20-year-old man who experienced left low quadrant pain after undergoing colonoscopy. Hemoperitoneum was diagnosed using abdominal CT. A laparoscopic exploration was urgently performed, revealing a lacerated mesocolon of the descending colon. Bleeding of the injured site was controlled without complication. The patient recovered fully without signs of recurrent bleeding. This report implies that if the patient has persistent abdominal pain after undergoing colonoscopy, we should consider hemoperitoneum as one of the causes. To the best of our knowledge, no case of isolated laceration of the mesocolon of the descending colon after colonoscopy has been reported. (Korean J Gastroenterol 2014;63:313-315).
Preview · Article · May 2014 · The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi
[Show abstract][Hide abstract] ABSTRACT: Background: Insulin is an important osteotropic hormone, but may be negatively associated with bone mass after adjustment for body mass index in adolescent populations. However, the association between insulin and bone mass in adults remains unclear. Objective: To investigate whether insulin was associated with bone mass in adults, and if so, whether the association was positive or negative. Design: Cross-sectional, using data from the Fourth Korea National Health and Nutrition Examination Survey (KNHANES) 2008-2009 and the U.S. National Health and Nutrition Examination Survey (NHANES) 1999-2006. Setting: Korean and U.S. Population Participants: 7271 KNHANES and 3399 NHANES participants were included. Main Outcome Measures: Anthropometric parameters and bone mass data, fasting glucose and insulin, height, weight, and markers related to insulin resistance. Results: After adjusting for confounding factors, there was an inverse relationship between insulin and total body bone mineral content (BMC) in the KNHANES and NHANES subjects. In a stratified analysis, an association between insulin and bone mass was apparent, especially in the highest homeostatic model of assessment of insulin resistance (HOMA-IR) quartile in the Korean subjects. However, this association was only seen in men in the U.S. subjects. Conclusions: There is an inverse relationship between insulin and total body BMC after adjustment for confounding factors in Korean and U.S. subjects, especially in the insulin-resistant population. This strongly suggests that the adverse influence of insulin on bone mass likely reflects the effects of other factors associated with insulin resistance rather than being a direct action of insulin itself.
Full-text · Article · Jan 2014 · The Journal of Clinical Endocrinology and Metabolism
[Show abstract][Hide abstract] ABSTRACT: Neurolymphomatosis (NL) is a rare clinical disease where neoplastic cells invade the cranial nerves and peripheral nerve roots, plexus, or other nerves in patients with hematologic malignancy. Most NL cases are caused by B-cell non-Hodgkin's lymphoma (NHL). Diagnosis can be made by imaging with positron emission tomography (PET) and magnetic resonance imaging (MRI). We experienced two cases of NL involving the brachial plexus in patients with NHL. One patient, who had NHL with central nervous system (CNS) involvement, experienced complete remission after 8 cycles of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy but relapsed into NL of the brachial plexus 5 months later. The other patient, who suffered from primary central nervous system lymphoma (PCNSL), had been undergoing chemoradiotherapy but progressed to NL of the brachial plexus.
Preview · Article · Nov 2013 · Case Reports in Oncological Medicine
[Show abstract][Hide abstract] ABSTRACT: The Escherichia coli XL1-blue strain was metabolically engineered to synthesize poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] through 2-ketobutyrate, which is generated via citramalate pathway, as a precursor for propionyl-CoA. Two different metabolic pathways were examined for the synthesis of propionyl-CoA from 2-ketobutyrate. The first pathway is composed of the Dickeya dadantii 3937 2-ketobutyrate oxidase or the E. coli pyruvate oxidase mutant (PoxB L253F V380A) for the conversion of 2-ketobutyrate into propionate and the Ralstonia eutropha propionyl-CoA synthetase (PrpE) or the E. coli acetyl-CoA:acetoacetyl-CoA transferase for further conversion of propionate into propionyl-CoA. The second pathway employs pyruvate formate lyase encoded by the E. coli tdcE gene or the Clostridium difficile pflB gene for the direct conversion of 2-ketobutyrate into propionyl-CoA. As the direct conversion of 2-ketobutyrate into propionyl-CoA could not support the efficient production of P(3HB-co-3HV) from glucose, the first metabolic pathway was further examined. When the recombinant E. coli XL1-blue strain equipped with citramalate pathway expressing the E. coli poxB L253F V380A gene and R. eutropha prpE gene together with the R. eutropha PHA biosynthesis genes was cultured in a chemically defined medium containing 20 g/L of glucose as a sole carbon source, P(3HB-co-2.3 mol% 3HV) was produced up to the polymer content of 61.7 wt.%. Moreover, the 3HV monomer fraction in P(3HB-co-3HV) could be increased up to 5.5 mol% by additional deletion of the prpC and scpC genes, which are responsible for the metabolism of propionyl-CoA in host strains.
No preview · Article · Oct 2013 · Applied Microbiology and Biotechnology
[Show abstract][Hide abstract] ABSTRACT: Increasing concerns about limited fossil fuels and global environmental problems have focused attention on the need to develop sustainable biofuels from renewable resources. Although microbial production of diesel has been reported, production of another much in demand transport fuel, petrol (gasoline), has not yet been demonstrated. Here we report the development of platform Escherichia coli strains that are capable of producing short-chain alkanes (SCAs; petrol), free fatty acids (FFAs), fatty esters and fatty alcohols through the fatty acyl (acyl carrier protein (ACP)) to fatty acid to fatty acyl-CoA pathway. First, the β-oxidation pathway was blocked by deleting the fadE gene to prevent the degradation of fatty acyl-CoAs generated in vivo. To increase the formation of short-chain fatty acids suitable for subsequent conversion to SCAs in vivo, the activity of 3-oxoacyl-ACP synthase (FabH), which is inhibited by unsaturated fatty acyl-ACPs, was enhanced to promote the initiation of fatty acid biosynthesis by deleting the fadR gene; deletion of the fadR gene prevents upregulation of the fabA and fabB genes responsible for unsaturated fatty acids biosynthesis. A modified thioesterase was used to convert short-chain fatty acyl-ACPs to the corresponding FFAs, which were then converted to SCAs by the sequential reactions of E. coli fatty acyl-CoA synthetase, Clostridium acetobutylicum fatty acyl-CoA reductase and Arabidopsis thaliana fatty aldehyde decarbonylase. The final engineered strain produced up to 580.8 mg l -1 of SCAs consisting of nonane (327.8 mg l-1), dodecane (136.5 mg l-1), tridecane (64.8 mg l-1), 2-methyl-dodecane (42.8 mg l-1) and tetradecane (8.9 mg l-1), together with small amounts of other hydrocarbons. Furthermore, this platform strain could produce short-chain FFAs using a fadD-deleted strain, and short-chain fatty esters by introducing the Acinetobacter sp. ADP1 wax ester synthase (atfA) and the E. coli mutant alcohol dehydrogenase (adhE mut).
[Show abstract][Hide abstract] ABSTRACT: Short sleep duration has been reported to increase the risk of diabetes. However, the influence of sleep duration on glycemic control in diabetic patients has not been clarified. In this study we evaluated the association between sleep duration and glycemic control in diabetic patients. We analyzed the data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2007-2010. Sleep duration was classified into five groups: <6, 6, 7, 8, and ≥9 h/day. Fasting blood glucose and HbA1c showed a U-shaped trend according to sleep duration. Sleep duration of 7 h/day had the lowest HbA1c (7.26%) among the subjects (P=0.026). In the older age group (≥65 yr), a sleep duration of 6 h/day was associated with the lowest HbA1c (7.26%). The adjusted odds ratio (OR) with a 95% confidence interval (CI) of worse glycemic control (HbA1c ≥7.0%) in group of sleep duration of ≥9 h/day was 1.48 (1.04-2.13) compared with the group of 7 h/day. This relationship disappeared after adjusting duration of diabetes (OR, 1.38; 95% CI, 0.93-2.03). Our results suggest that sleep duration and glycemic control in diabetic patients has U-shaped relationship which was mainly affected by duration of diabetes.
Full-text · Article · Sep 2013 · Journal of Korean medical science
[Show abstract][Hide abstract] ABSTRACT: Occupation affects bone mineral density (BMD); however, only few studies have been published. This study evaluated the effect of working time during a day on BMD. The cross-sectional study involved 18- to 50-year-old people who reported their working time and were measured for BMD using dual-energy X-ray absorptiometry in the Fourth Korea National Health and Nutrition Examination Survey 2009. The time period of work was divided into "daytime" and "other than daytime." The other-than-daytime group included evening time, nighttime, regular shift time, and irregular shift time. Among 3,005 subjects, 2,378 were daytime workers and 627 were other-than-daytime workers. The mean BMD of the total femur and lumbar spine were significantly lower in other-than-daytime workers compared to daytime workers (femur 0.948 vs. 0.966 g/cm(2), respectively, p = 0.001; lumbar spine 0.976 vs. 0.988 g/cm(2), respectively, p = 0.023). The other-than-daytime group had lower levels of serum 25-hydroxyvitamin D than the daytime group (16.3 vs. 17.6 ng/mL, p < 0.001). The proportion of osteopenia (T score < -1.0) was higher in the other-than-daytime than the daytime group (34.3 vs. 29.1 %, p = 0.014). After adjustment for age, sex, socioeconomic status, lifestyle factors, daily intake of calcium, and vitamin D level, the relative risks of osteopenia of regular-shift and irregular-shift workers were significantly higher (1.65, 95 % CI 1.05-2.60; 1.78, 95 % CI 1.09-2.89) than those of daytime workers. These data suggest that other-than-daytime working, especially regular and irregular shift working, is associated with decreased BMD and increased risk for osteopenia in Korean adults.
Full-text · Article · Aug 2013 · Calcified Tissue International
[Show abstract][Hide abstract] ABSTRACT: We investigated the association between suicidal ideation and diabetes in Korean adults with and without depression. Diabetes is a significant risk factor for suicidal ideation and the coexistence of diabetes and depression was associated with a much higher risk of suicidal ideation than with diabetes alone.
No preview · Article · Jul 2013 · Diabetes research and clinical practice
[Show abstract][Hide abstract] ABSTRACT: Alendronate is one of the most potent anti-osteoporotic agents for postmenopausal osteoporosis. However, high doses of alendronate cause esophageal irritation, myalgia, gastrointestinal discomfort and decrease of serum calcium level. Recently, Maxmarvil® was developed as an enteric-coated tablet containing alendronate (5 mg) and calcitriol (0.5 μg) to minimize these side effects of alendronate. In the present study, we evaluated the pharmacokinetic profile and examined the incidence of unfavorable effects after oral administration of Maxmarvil® in Korean healthy postmenopausal women without a previous history of fracture. In the in vitro dissolution test, alendronate was not released from Maxmarvil® in pH 1.2 phosphate buffer solution but released in pH 6.0 and 6.8 phosphate buffer solutions and completely dissolved in 30 min. After oral administration of Maxmarvil®, three out of 18 (16.7 %) women showed mild adverse effects; two myalgia and one upper gastrointestinal discomfort without heartburn. Most of these complaints disappeared during the study without additional treatment. The peak (U
max) and the average (U
ave) urinary excretion rate of alendronate and the time to reach U
max) were 2.94 μg/h, 0.901 μg/h and 6.77 h, respectively. The total cumulative urinary excretion of alendronate (Ae0–24 h) was 21.6 μg (0.432 % of oral alendornate), which was similar to the reported values. Taken together, enteric-coated Maxmarvil® is less harmful for the esophagus and gastrointestinal mucosa, shows the same pharmacokinetic profile to conventional alendronate (70 mg) and improves the tolerability of medication in clinical practice.
No preview · Article · May 2013 · Archives of Pharmacal Research
[Show abstract][Hide abstract] ABSTRACT: Background/aims:
Visfatin is an adipocytokine predominantly expressed in visceral adipose tissue. We examined the relationship between plasma visfatin concentrations and anthropometric and metabolic parameters in children and adolescents, who are relatively less influenced by the effects of accompanying disease.
We studied 135 children and adolescents (8-16 years old). Plasma glucose, insulin, lipid profile, visfatin and other adipocytokine levels were measured. CT scans were performed to evaluate the distribution of abdominal fat. We analyzed the relationship between circulating visfatin levels and anthropometric and metabolic parameters according to central adiposity (total abdominal fat by CT scan).
In the lower-adiposity group, plasma visfatin concentrations were significantly correlated with total abdominal fat, visceral fat, subcutaneous abdominal fat, plasma triglyceride level and homeostasis model assessment of insulin resistance (HOMA-IR). In a multiple linear regression analysis, visceral fat and triglycerides were independently associated with plasma visfatin levels. In the higher-adiposity group, plasma visfatin concentrations were not correlated with visceral fat or HOMA-IR but were significantly correlated with circulating interleukin-6 levels.
These data suggest that the relationship between plasma visfatin concentrations and metabolic parameters differs according to central adiposity and that plasma visfatin concentrations are correlated with visceral fat and triglyceride levels, especially in children and adolescents with lower adiposity.
No preview · Article · Apr 2013 · Hormone Research in Paediatrics
[Show abstract][Hide abstract] ABSTRACT: Platform chemicals composed of 2-6 carbons derived from fossil resources are used as important precursors for making a variety of chemicals and materials, including solvents, fuels, polymers, pharmaceuticals, perfumes, and foods. Due to concerns regarding our environment and the limited nature of fossil resources, however, increasing interest has focused on the development of sustainable technologies for producing these platform chemicals from renewable resources. The techniques and strategies for developing microbial strains for chemicals production have advanced rapidly, and it is becoming feasible to develop microbes for producing additional types of chemicals, including non-natural molecules. In this study, we review the current status of the bio-based production of major C2-C6 platform chemicals, focusing on the microbial production of platform chemicals that have been used for the production of chemical intermediates, building block compounds, and polymers.
Full-text · Article · Oct 2012 · Biotechnology and Bioengineering
[Show abstract][Hide abstract] ABSTRACT: Three different submerged membrane hybrid systems (SMHSs) namely submerged membrane coagulation hybrid system (SMCHS), submerged membrane adsorption hybrid system (SMAHS), and submerged membrane coagulation–adsorption hybrid system (SMCAHS) were studied as pretreatment systems to seawater reverse osmosis (SWRO). The performances of these SMHSs were compared with that of submerged membrane system (without any coagulation or adsorption) in terms of trans-membrane pressure (TMP) development, critical flux, ultrafilter modified fouling index (UF-MFI), dissolved organic carbon (DOC) removal efficiency, and the removal of detailed organic fractions. The experimental results show that pretreatment by SMCAHS led to the best results in terms of organic removal and critical flux. With the low doses of ferric chloride (FeCl3) and powder activated carbon (PAC) of 0.5 mg of Fe3+/L and 0.5 g of PAC/L, respectively, this hybrid system could remove 72% of DOC and reduce the UF-MFI nearly five times. The initial DOC and UF-MFI of seawater used in this study were 2.53 mg/L and 14,165 s/L2, respectively. The application of three different membrane fouling models namely pore blockage, pore constriction, and cake formation models showed that cake formation was the predominant fouling mechanisms causing fouling in SMHSs.
[Show abstract][Hide abstract] ABSTRACT: For the prevention of osteoporotic fracture, adequate screening and treatment are important. However, there are few published data on diagnosis and treatment rates of osteoporosis in Asia. We used data from the fourth Korea National Health and Nutrition Examination Survey 2008-2009 to estimate the nationwide prevalence, physician diagnosis rate, and treatment rate of osteoporosis in adults aged 50 years and older. The bone mineral density (BMD) measurements of central skeletal sites (lumbar spine, femoral neck, and total hip) were obtained using dual-energy X-ray absorptiometry (DXA) (Discovery-W; Hologic Inc., Waltham, MA, USA). Diagnosis of osteopenia or osteoporosis was defined by the World Health Organization (WHO) T-score criteria. The prevalence of osteoporosis in adults aged 50 years or older was 35.5% in women and 7.5% in men. The prevalence of osteoporosis in Korea was similar to other East Asian countries but higher than that in Caucasians. Lumbar spine bone density T-scores tended to be lower than those of the femoral neck or hip. The estimated diagnosis rate was 26.2% (women 29.9%, men 5.8%) and the treatment rate was 12.8% (women 14.4%, men 4.0%). The physician diagnosis rate was significantly higher in females aged 66 to 68 years who were the beneficiaries of the national screening program than that in females of other ages (43.6% versus 28.1%, p < 0.05). The national screening program for osteoporosis may have contributed to an increased diagnosis rate in older Korean women. However, it was evident that treatment following a diagnosis of osteoporosis was still inadequate.
Full-text · Article · Sep 2012 · Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research