Causal Effect of Chondroitin, Glucosamine, Vitamin, and Mineral Intake on Kidney Function: A Mendelian Randomization Study

The causal effects of chondroitin, glucosamine, and vitamin/mineral supplement intake on kidney function remain unknown, despite being commonly used. We conducted a two-sample summary-level Mendelian randomization (MR) analysis to test for causal associations between regular dietary supplement intake and kidney function. Genetic instruments for chondroitin, glucosamine, and vitamin/mineral supplement intake were obtained from a genome-wide association study of European ancestry. Summary statistics for the log-transformed estimated glomerular filtration rate (log-eGFR) were provided by the CKDGen consortium. The multiplicative random-effects inverse-variance weighted method showed that genetically predicted chondroitin and glucosamine intake was causally associated with a lower eGFR (chondroitin, eGFR change beta = -0.113%, standard error (SE) = 0.03%, p-value = 2 × 10-4; glucosamine, eGFR change beta = -0.240%, SE = 0.035%, p-value = 6 × 10-12). However, a genetically predicted vitamin/mineral supplement intake was associated with a higher eGFR (eGFR change beta = 1.426%, SE = 0.136%, p-value = 1 × 10-25). Validation analyses and pleiotropy-robust MR results for chondroitin and vitamin/mineral supplement intake supported the main results. Our MR study suggests a potential causal effect of chondroitin and glucosamine intake on kidney function. Therefore, clinicians should carefully monitor their long-term effects.

Predisposing factors associated with atypical femur fracture among postmenopausal Korean women receiving bisphosphonate therapy: 8 years' experience in a single center

The risk factors for atypical femur fracture in patients exposed to bisphosphonates for at least 1 year were examined. Prolonged and continuous use of bisphosphonates, long-term use of glucocorticoids, and a higher body mass index were associated with increased risk of atypical femur fracture.

INTRODUCTION

The purpose of the present study is to determine whether rheumatoid arthritis (RA) and other clinical factors are associated with an increased risk of bisphosphonate (BP)-related atypical femur fracture (AFF).

METHODS

A retrospective nested case-control study of patients who had taken BPs for at least 1 year was conducted. Patients with AFF were identified by reviewing surgical and radiographic records. Three controls with no history of AFFs were randomly selected and age- and sex-matched to each patient with AFFs. Cox proportional hazard models were used to analyze the independent contribution of risk factors to BP-related AFF.

RESULTS

Among the 35,104 patients prescribed BPs for at least 1 year, 43 females (mean age, 68 years) suffered AFFs (0.12%). Patients with AFFs were exposed to BPs for a mean of 7.3 years. Patients with AFFs were exposed to BPs for longer than those without AFFs and continued treatment without a drug holiday. More patients with AFF than controls had taken glucocorticoids and disease-modifying anti-rheumatic drugs. Multivariate Cox regression analyses estimated that long-term use of glucocorticoids, prolonged exposure to BP without cessation, and every 1 kg/m² increase in the body mass index (BMI) increased the hazard ratio for AFFs by 3.0, 5.2, and 1.2, respectively.

CONCLUSIONS

Prolonged and continuous use of BPs, long-term use of glucocorticoids, and a higher BMI increase the risk of AFFs. Switching long-term BP and glucocorticoid users to other bone-protective agents should be considered.

Functional Epitopes for Anti-Aquaporin 5 Antibodies in Sjögren Syndrome

We recently reported the presence of anti-aquaporin 5 (AQP5) immunoglobulin G (IgG) in patients with primary Sjögren syndrome (SS) with a sensitivity of 0.73 and a specificity of 0.68. The aim of this study was to identify functional epitopes for the anti-AQP5 autoantibodies detected in control subjects and patients with SS. Recognition of epitopes by anti-AQP5 autoantibodies in sera ( n = 13 for control and n = 24 for SS) or purified IgG ( n = 1 for control and n = 3 for SS) was evaluated by indirect immunofluorescence (IIF) assay performed in the presence or absence of peptides corresponding to the second transmembrane helix and extracellular loops A, C, and E of AQP5. Functional epitopes were determined by measuring the effects of purified IgG and neutralizing peptides on transepithelial osmotic permeability (P_f^T) of MDCK cells expressing AQP5. In the IIF assay, 89% of SS samples were inhibited by at least 1 peptide, while only half of control samples were inhibited by any peptide. Overall, SS samples were inhibited by peptides corresponding to extracellular loops A, C, and E by 40% to 50%, whereas control samples were inhibited only by peptides corresponding to loop E by <20%. A cyclized peptide (E1) mimicking loop E was most frequently recognized and best differentiated between the SS and control samples. Incubation of MDCK-AQP5 cells with SS but not with control IgG, significantly decreased P_f^T, which was reversed by neutralization of IgG binding to any of the extracellular loops. In conclusion, the anti-AQP5 autoantibodies detected in control and SS groups showed differences in fine specificity to the functional epitopes of AQP5. The prevalent recognition of functional epitopes by anti-AQP5 autoantibodies from SS patients suggests that anti-AQP5 autoantibodies act as mediators of glandular hypofunction and are a potential therapeutic target in SS.

Lupus cystitis in Korean patients with systemic lupus erythematosus: risk factors and clinical outcomes

This study was performed to investigate the clinical characteristics of lupus cystitis and determine the risk factors and clinical outcomes of lupus cystitis in patients with systemic lupus erythematosus (SLE). We retrospectively reviewed 1064 patients at Seoul St. Mary’s Hospital in Seoul, Korea, from 1998 to 2013. Twenty-four patients had lupus cystitis. Lupus cystitis was defined as unexplained ureteritis and/or cystitis as detected by imaging studies, cystoscopy, or bladder histopathology without urinary microorganisms or stones. Three-fourths of patients with lupus cystitis had concurrent lupus mesenteric vasculitis (LMV). The initial symptoms were gastrointestinal in nature for most patients (79.2%). High-dose methylprednisolone was initially administered to most patients (91.7%) with lupus cystitis. Two patients (8.3%) died of urinary tract infections. Sixty-five age- and sex-matched patients with SLE who were admitted with other manifestations were included as the control group. Patients with lupus cystitis showed a lower C3 level ( p = 0.031), higher SLE Disease Activity Index score ( p = 0.006), and higher ESR ( p = 0.05) upon admission; more frequently had a history of LMV prior to admission ( p < 0.001); and less frequently had a history of neuropsychiatric lupus ( p = 0.031) than did patients with SLE but without lupus cystitis. The occurrence of lupus cystitis was associated with a history of LMV (OR, 21.794; 95% CI, 4.061–116.963). The median follow-up period was 3.4 years, and the cumulative one-year mortality rate was 20%. Complications developed in 33.3% of patients with lupus cystitis and were related to survival (log-rank p = 0.021). Our results suggest that the possibility of lupus cystitis should be considered when a patient with SLE and history of LMV presents with gastrointestinal symptoms or lower urinary tract symptoms. Development of complications in patients with lupus cystitis can be fatal. Thus, intensive treatment and follow-up are needed, especially in the presence of complications.

Pregnancy and patients with preexisting lupus nephritis: 15 years of experience at a single center in Korea

We investigated obstetric outcomes and comorbidities during pregnancy in females with preexisting lupus nephritis (LN) and identified predictors for renal flare. In cases of renal flare during pregnancy, we assessed the long-term post-delivery renal outcome. We performed a retrospective analysis of 183 systemic lupus erythematosus (SLE) pregnancies including blood chemistry, urinalysis, urinary protein, and disease activity recorded at prepregnancy, during pregnancy, and at one month, six months, and one year post-delivery. Pregnancies with preexisting LN had a greater frequency of adverse obstetric outcomes and maternal comorbidity. Renal flares occurred in 50.7% of pregnancies with preexisting LN, 89.2% of which were reactivations. Renal flare among pregnancies with SLE was predicted based on preexisting lupus nephritis (OR 17.73; 95% CI, 5.770–54.484), an active disease prior to pregnancy (OR 2.743; 95% CI, 1.074–7.004), and prepregnancy eGFR < 90 ml/min/1.73 m2 (OR 11.151; 95% CI, 3.292–37.768).

Persistent LN one year after delivery was observed in 33.3% of pregnancies. The median follow-up time after delivery was 5.9 (3.1–9.7) years and chronic kidney disease (CKD) occurred in 21.4% of pregnancies with renal flare. In patients with renal flare, failing to achieve a ≥ 50% reduction in urine protein levels within six months, longer total duration of renal flare, and acute kidney injury at renal flare was associated with CKD development. Females with preexisting LN should achieve remission before pregnancy. When patients experience renal flares during pregnancy, it is important to reduce the proteinuria level by >50% within six months and to achieve early remission for excellent long-term renal outcomes.

Hydroxychloroquine and pregnancy on lupus flares in Korean patients with systemic lupus erythematosus

We investigated the clinical and laboratory characteristics of pregnancies with systemic lupus erythematosus (SLE) and identified lupus flare predictors during pregnancy. Additionally, we examined lupus activity and pregnancy outcomes in SLE patients who continued, discontinued or underwent no hydroxychloroquine (HCQ) treatment during pregnancy. We retrospectively analyzed 179 pregnancies in 128 SLE patients at Seoul St. Mary’s Hospital, Korea, between 1998 and 2012 and then assessed the clinical profiles and maternal and fetal outcomes. Overall, 90.5% of pregnancies resulted in a successful delivery and were divided into two groups: those who experienced lupus flares (80 pregnancies, 44.7%) and those who did not (99 pregnancies, 55.3%). Increased preeclampsia, preterm births, low birth weight, intrauterine growth restriction (IUGR), and low 1-minute Apgar scores occurred in pregnancies with lupus flares compared to pregnancies in quiescent disease. Lupus flares were predicted by HCQ discontinuation, a history of lupus nephritis, high pre-pregnancy serum uric acid and low C4 levels. Our study indicates that achieving pre-pregnancy remission and continuing HCQ treatment during pregnancy are important for preventing lupus flares.

Relationship between gamma-glutamyltransferase and metabolic syndrome in a Korean population

AIMS

To investigate associations between gamma-glutamyltransferase (GGT) and components of metabolic syndrome (MS), insulin resistance and inflammatory markers in the Korean population.

METHODS

The 3508 subjects enrolled in this survey participated in the Korean Rural Genomic Cohort (KRGC) study. Written consent was obtained from the local ethical committee. Of these participants, 1437 were men (mean age 56.9 +/- 7.9 years) and 2071 were women (mean age 55.8 +/- 8.1 years). We measured GGT levels and various biochemical markers. To examine insulin resistance status, we used the homeostasis assessment method for insulin resistance (HOMA-IR). For inflammatory marker, we used C-reactive protein (CRP) levels.

RESULTS

Serum GGT levels were significantly higher in the MS group compared to the healthy patient group [23 (5-1403) vs. 19 (5-1920) IU/l; P = 0.01]. The prevalence of MS and adjusted relative risk were both significantly increased from the lowest to highest GGT quartiles; these results persisted after adjustments for multiple confounders. Positive correlations were established between GGT and HOMA-IR or CRP.

CONCLUSION

These results suggest that GGT levels may be a surrogate marker of insulin resistance, inflammation and MS.

Production of mycelia and exo-biopolymer from molasses by Cordyceps sinensis 16 in submerged culture

The molecular weight of exo-biopolymer obtained from a submerged culture of Cordyceps sinensis 16 consisted of a main unit and a subunit of 126 and 68 kDa, respectively. The optimal medium for the production of mycelia and exo-biopolymer was determined to be molasses containing 2% sucrose, 0.9% yeast extract, 0.3% K2HPO4, and 0.4% CaCl2. Using optimized medium, maximum productions of mycelia and exo-biopolymer in shake-flask culture were 54.0 g/L and 28.4 g/L, respectively. This study suggests that large-scale production of mycelia and exo-biopolymer by C. sinensis 16 is possible in submerged culture.

Biological activities of Saccharomyces cerevisiae and fermented rice bran as feed additives

AIMS

The objective of the present study was to examine for the various biological activities for feed additives of Saccharomyces cerevisiae and fermented rice bran.

METHODS

The feed additives (100 g of each: YE, brewery yeast; PM, mixture of YE and SF; SF, fermented rice bran) were decocted with 2 l water at 100 degrees C to a half volume.

RESULTS

The hot-water extract of PM was found to increase the stimulation of the macrophage activation (2.0-fold) and the intestinal immune modulating activity (1.8-fold), compared with those of control. When the hot-water extracts of PM, SF and YE were fed to the rats for 8 d (1 g kg-1 d-1), PM and SF showed the more effective anti-stress effect on spleen, thyroid and thymus gland.

SIGNIFICANCE AND IMPACT OF THE STUDY

The hot-water extract of PM can have a significant impact on strengthening the living body's immune system and proliferating anti-stress activities with relation to enhance immunity.

Comparison of the efficacy and safety of naproxen CR and nabumetone in the treatment of patients with osteoarthritis of the knee

OBJECTIVE

To comparre the safety and efficacy of naproxen CR (1,000 mg once daily) with that of nabumetone (1,000 mg once daily) in the treatment of patients with symptomatic knee osteoarthritis(OA).

METHODS

A total of 159 Korean patients (80 in the naproxen CR group and 79 in the nabumetone group) were enrolled in this 4-week, single-blind, controlled, randomized, parallel study and an intention-to-treat model was used for data analysis. Six efficacy parameters were measured: Lequesne index, visual analogue pain scale at rest and atactivity, patient's and physician's global assessment, and time to walk 50 feet.

RESULTS

Significant improvement in all efficacy parameters except time to walk 50 feet occurred at Week 2 and Week 4 in both groups. Themean improvement from baseline at Week 2 and Week 4 for the efficacy variables was not different between naproxen CR and nabumetone group. Twenty-four patients (30%) in the naproxen CR group and 18 patients (22.8%) in the nabumetone group withdrew from the study. Among them, only 1patient in the naproxen CR group terminated the study prematurely due to an adverse event of dyspepsia. No statistically significant difference in the frequency of adverse events, including gastrointestinal symptoms, was observed between these 2 groups during the treatment period. Significant laboratory abnormalities also did not occur during the study period in both groups.

CONCLUSIONS

Naproxen CR is an effective and tolerable drug in the treatment of knee OA. Efficacy and safety profiles are comparable to those of nabumetone.

Anti-stress and anti-fatigue effects of fermented rice bran

The anti-stress and anti-fatigue effects on rats and mice of a hot water extract of rice bran fermented with Saccharomyces cerevisae IFO 2346 were investigated. Oral administration (1 g/kg/day) of the hot water extract of fermented rice bran (FRB) inhibited major changes in the weight of the adrenal, thymus, spleen and thyroid, showing an anti-stress effect. The hot water extract of FRB also inhibited increases in the GPT and LDH activity, cholesterol and glucose in the serum. The administration (1 g/kg/day) for 2 weeks significantly prolonged the swimming time, resulting in an increase in the anti-fatigue effect. It is considered from these results that FRB had anti-stress and anti-fatigue effects.

Asymmetric Pt(II)-Catalyzed Ene Reactions: Counterion-Dependent Additive and Diphosphine Electronic Effects1

[reaction: see text]. Catalysis of the glyoxylate-ene reaction by dicationic P2Pt(II) complexes is subject to anion-dependent additive effects. For [((S)-MeOBiphep)Pt](OTf)2 catalysts, acidic phenols such as 3-CF3-C6H3OH or C6F5OH provide substantial rate increases but do not affect the more active SbF6-based catalysts. Enantioselectivity and reactivity also increased with diphosphine basicity, with 4-t-Bu-substituted MeOBiphep ligands yielding the highest enantioselectivities.

Pulmonary alveolar hemorrhage in patients with rheumatic diseases in Korea

Pulmonary alveolar hemorrhage (PAH) is a rare and often fatal presenting feature of rheumatic diseases, with high mortality rate ranging from 40% to 90%. This study was undertaken to review the clinical manifestations, disease course, prognosis, and treatment of PAH in rheumatic diseases in Korea. A retrospective analysis was performed from October 1995 to March 1999 at the Samsung Medical Center. Ten cases were diagnosed as having pulmonary hemorrhage with rheumatic diseases that comprised the following: 6 systemic lupus erythematosus (SLE), 3 microscopic polyangiitis (MPA), and 1 mixed connective tissue disease (MCTD). In 80% of the patients in the present series, PAH was the first clinical manifestation of rheumatic diseases. The most consistent systemic manifestation occurring in conjunction with PAH was renal involvement (80%). The overall patient mortality rate was 50% (5/10) in the current series. Our study suggests that PAH often occurs as the first clinical manifestation of rheumatic diseases and needs urgent medical treatment including plasmapheresis in addition to cyclophosphamide and methylprednisolone.

Practical ruthenium/lipase-catalyzed asymmetric transformations of ketones and enol acetates to chiral acetates

Ketones were asymmetrically transformed to chiral acetates by one-pot processes using a lipase and an achiral ruthenium complex under 1 atm of hydrogen gas in ethyl acetate. Molecular hydrogen was also effective for the transformation of enol acetates to chiral acetates without additional acyl donors with the same catalyst system.

Dynamic kinetic resolution of allylic alcohols mediated by ruthenium- and lipase-based catalysts

An enzyme-metal combo reaction has been developed for the dynamic kinetic resolution of allylic alcohols in which racemic substrates are transformed by a lipase and a ruthenium complex in the presence of an acyl donor to allylic acetates of high optical purity in over 80% yield.

Fluorine-18 fluorodeoxyglucose imaging using dual-head coincidence positron emission tomography without attenuation correction in patients with head and neck cancer

PURPOSE

An accurate, preoperative assessment of tumor extent and lymph node involvement is necessary to plan and tailor therapy for patients with head and neck cancer. Metabolic imaging with fluorine-18 fluorodeoxy-glucose (FDG) is a good method to detect primary tumors in the head and neck and to assess the involvement of lymph nodes, but it is not widely available because of the high cost of positron emission tomography (PET). Recently, an alternative method for using FDG was developed: coincidence detection PET (CoDe PET) using a gamma camera. The aim of this study was to evaluate the clinical utility of FDG CoDe PET using a gamma camera in patients with head and neck cancer.

MATERIALS AND METHODS

Thirty FDG CoDe PET studies without attenuation correction were performed in seven patients before therapy and in 19 patients after therapy (ages: 25-79 years, mean, 50 +/- 13 years; 18 men, 8 women) with various head and neck cancers. All patients had fasted for 6 to 12 hours and were injected with 111 to 370 MBq F-18 FDG 1 hour before imaging. Visually detectable focal FDG uptake in the primary tumor site or in the neck was considered positive except for physiologic uptake. The FDG CoDe PET studies were correlated with MRI. The gold standard for the presence of disease was the combination of repeated MRIs, endoscopic examination, and 3 months of follow-up clinical evaluation.

RESULTS

FDG CoDe PET had a detection rate that was comparable to that of MRI in the pretherapy group. However, in the posttherapy group, FDG CoDe PET could differentiate residual tumor or tumor recurrence from radiation change more accurately than could MRI. However, it had a less accurate detection rate for cervical node metastases because of asymmetric neck muscle uptake.

CONCLUSIONS

FDG CoDe PET is a sensitive and cost-effective method to detect primary tumor and lymph node involvement in primary head and neck cancers. It is also useful in differentiating residual tumor or tumor recurrence from posttherapy changes in patients with head and neck tumors.

Effect of the column length on the characteristics of the packed bed and the column efficiency in a dynamic axial compression column

The axial homogeneity of preparative-scale chromatography columns was studied by measuring the overall properties of similar columns differing only by their lengths. The properties investigated were the packing density, the external porosity, the permeability and the column efficiency. Two different materials were used, one made of large, irregular silica particles compressed under either high or a low degree of stress; the other of small, spherical and rigid particles. The columns made with the spherical particles were more homogeneous, had a higher external porosity and specific permeability, and a higher efficiency than those made with the irregular ones. For this latter material, the columns prepared with a low level of stress were better than those compressed under high stress. The latter ones experienced extensive particle breakage. These results indicate that the long columns are heterogeneous in their axial direction.

Consolidation of particle beds and packing of chromatographic columns

A variety of complementary evidence reviewed here demonstrates that the packing of chromatographic columns is heterogeneous. It is denser and less well organized close to the column wall than in the center of the column. The mechanism of particle consolidation under stress explains the origin of this phenomenon and provides a fundamental justification to what is known in column chromatography as "the wall effect".