Urate Transporter ABCG2 Function and Asymptomatic Hyperuricemia: A Retrospective Cohort Study of CKD Progression

RATIONALE & OBJECTIVE

Treatment of asymptomatic hyperuricemia is not commonly implemented. However, it is unclear whether urate deposition that begins during asymptomatic hyperuricemia can induce nephropathy. Dysfunction of ATP-binding cassette subfamily G member 2 (ABCG2), a urate efflux transporter, leads to elevated serum uric acid concentration (SUA). We investigated the association between asymptomatic hyperuricemia and decreased estimated glomerular filtration rate (eGFR), and the impact of ABCG2 on this relationship.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

1,885 Japanese adults undergoing routine health care follow-up between 2007 and 2017 who had eGFR ≥60 mL/min/1.73 m², of which 311 had asymptomatic hyperuricemia (SUA >7.0 mg/dL). Study participants were classified into 3 categories of estimated ABCG2 function (full, 75%, and ≤50% function).

PREDICTORS

Baseline SUA and estimated ABCG2 function.

OUTCOME

Change in eGFR over time.

ANALYTICAL APPROACH

Linear mixed-effect models were used to analyze the relationship between asymptomatic hyperuricemia, ABCG2 function, and eGFR decline.

RESULTS

Asymptomatic hyperuricemia was negligibly associated with eGFR decline overall. However, among those with eGFR 60-89 mL/min/1.73 m² and ≤50% ABCG2 function, eGFR decline was associated with asymptomatic hyperuricemia (P = 0.03). ABCG2 was not associated with eGFR reductions when the SUA was <6.0 mg/dL. Among participants with SUA ≥6.0 mg/dL and eGFR 60-89 mL/min/1.73 m², ≤50% ABCG2 function was associated with approximately 1.2-fold faster eGFR decline compared with fully functional ABCG2 (P = 0.02). Among the participants with SUA ≥6.0 mg/dL and eGFR 60-89 mL/min/1.73 m², the adjusted eGFR slopes (given as mean ± standard error of the mean, in mL/min/1.73 m² per year) were -0.946 ± 0.049, -1.040 ± 0.046, and -1.148 ± 0.069 for full, 75%, and ≤50% ABCG2 function, respectively.

LIMITATIONS

Lack of measurement of urinary urate and uremic toxins that are known to be transported by ABCG2, and no independent validation cohort.

CONCLUSIONS

Asymptomatic hyperuricemia was not associated with eGFR decline, except when in the presence of ≤50% ABCG2 function.

PLAIN-LANGUAGE SUMMARY

The urate transporter ABCG2 is a protein that regulates serum urate concentrations; when dysfunctional, it can lead to elevated serum concentrations of this compound (ie, hyperuricemia). Although persistent hyperuricemia induces gout and kidney injury, the effects on organs during the asymptomatic phase have yet to be established. Therefore, to clarify the relationship between ABCG2, asymptomatic hyperuricemia, and kidney function, we conducted a retrospective cohort study of 1,885 healthy participants, including 311 participants with asymptomatic hyperuricemia. We found that the coexistence of asymptomatic hyperuricemia and severe ABCG2 dysfunction was associated with the age-dependent decline in kidney function. We concluded that asymptomatic hyperuricemia represents a risk factor for chronic kidney disease, at least in individuals with highly dysfunctional ABCG2. This new finding highlights the potential importance of ABCG2 in the pathogenesis of hyperuricemia-induced kidney injury.

Relationship between the housing coldness/warmth evaluation by CASBEE Housing Health Checklist and psychological distress based on TMM Community-Based Cohort Study: a cross-sectional analysis

OBJECTIVES

Previous studies have reported the relationship between housing environment and health, although due to cost and effort, it was difficult to conduct housing condition surveys on a large scale. The CASBEE Housing Health Checklist (the Checklist) made it possible to easily evaluate the housing condition from the resident's perspective. This study examined the relationship between housing coldness/warmth evaluation using the Checklist and psychological distress in a large-scale general Japanese population.

STUDY DESIGN

A cross-sectional study.

METHODS

We analysed data from 29,380 people aged ≥20 years who lived in Miyagi Prefecture, Japan. As an assessment of housing coldness/warmth, we used the Checklist. We classified participants' total scores on the Checklist related to coldness/warmth into quartiles. The Kessler 6 scale was used as an indicator of psychological distress. Multivariable logistic regression models were used to estimate the adjusted odds ratio (OR) and 95% confidence intervals (CIs). Adjusted OR and P-values for linear trends were calculated using the quartiles of the Checklists' score.

RESULTS

Among participants in Q1 (i.e., poorer subjective house condition), the percentage of people with psychological distress was high. Compared to the highest quartile, Q1 showed poorer evaluation of housing coldness/warmth, and higher OR for psychological distress. The OR (95% CI) of psychological distress for Q3, Q2, and Q1 compared with Q4 were 1.93 (1.74-2.14), 2.82 (2.55-3.12), and 5.78 (5.25-6.35), respectively.

CONCLUSIONS

Housing coldness/warmth evaluation was significantly related to psychological distress. This finding suggests that maintaining a comfortable thermal environment at home could be important for residents' mental health.

Relationship between the combination of polyunsaturated fatty acids intake and psychological distress during pregnancy: The Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study

No studies have examined the association of the combination of n-3 polyunsaturated fatty acids (PUFAs) and n-6 PUFAs intake with psychological distress during pregnancy. To examine these associations, we divided Japanese pregnant women into 25 groups based on combining quintiles of n-3 PUFAs intake and quintiles of n-6 PUFAs intake. We conducted multivariable logistic regression analyses to assess the risk of psychological distress during pregnancy (Kessler Psychological Distress Scale ≥ 5 or 13). Compared to the third quintile of both n-3 PUFAs and n-6 PUFAs intake, the groups with unbalanced intake, high intake of both, and low intake of both were associated with a higher risk of both Kessler Psychological Distress Scale ≥ 5 and 13 in early and mid-pregnancy. Further research is needed to identify the precise combination of n-3 PUFAs and n-6 PUFAs intake associated with the lowest psychological distress during pregnancy.

Association between polymorphism at IGF-1 rs35767 gene locus and long-term decline in renal function: a Japanese retrospective longitudinal cohort study

BACKGROUND

Insulin-like growth factor-1 (IGF-1) acts on glucose and protein metabolism and human growth and also influences blood pressure and renal function. This study investigated whether the single-nucleotide polymorphism of IGF-1, rs35767, plays a role in metabolic syndrome indicators, including blood pressure, glucose metabolism, uric acid levels, and renal function.

METHODS

In this retrospective longitudinal cohort study, blood samples from 1506 Japanese individuals were collected and used for genotyping for variant rs35767: T > C in the IGF-1 upstream promoter. Data were analyzed to identify associations between IGF-1 genotypes and patient biochemical parameters, including the components of metabolic syndrome and the long-term change in renal function.

RESULTS

The cohort rs35767 genotypes included 650 CC carriers (43.2%), 687 TC carriers (45.6%), and 169 TT carriers (11.2%). Multiple regression analysis revealed no association between IGF-1 genotype and blood pressure, glycated hemoglobin level, and serum uric acid level. However, in females, blood pressure was negatively correlated with the TT genotype. Longitudinal observation revealed that the decline in eGFR over 10 years was greater in TT (- 18.51 ± 1.04 mL/min/1.73m²) than in CC carriers (- 16.38 ± 0.52 mL/min/1.73m²; P < 0.05).

CONCLUSION

The present study suggests that renal function declines faster in individuals with the TT genotype at the IGF-1 rs35767 locus than in those with the CC genotype, suggesting that the TT genotype is associated with the long-term chronological decline in renal function.

A new insight into the treatment of renal anemia with HIF stabilizer

The long-term clinical experiences with recombinant human erythropoietin (rHuEPO) and its analog derivatives have clearly proven that correction of anemia with erythropoiesis stimulating agent (ESA) not only reduces blood transfusion and improves patients’ QOL but has multiple benefits for the concurrent complications of CKD such as Cardio-Renal–Anemia (CRA) syndrome and/or malnutrition-inflammation-atherosclerosis (MIA) syndrome.

Unlike ESA, the newly available agent, hypoxia-inducible factor (HIF) stabilizer, stimulates endogenous erythropoietin (EPO) by mimicking hypoxia with HIF prolyl hydroxylase domain enzyme (HIF-PHD) inhibition. The phase 2 and 3 clinical studies have shown that HIF stabilizers are as efficacious as ESA in ameliorating renal anemia. Whether the same clinical benefits on CRA and MIA syndrome hold true in patients given HIF stabilizers is a matter for future debate. Given that HIF stabilizers act on the multiple target genes, the use of this novel agent may lead to unwanted adverse events.

Launching HIF stabilizers into the treatment of renal anemia provokes a concern about how this alternative treatment will be taken up in the daily clinical practice. However, guideline-oriented strategies on how to use HIF stabilizer is not available at this limited point due to scant clinical information. Nevertheless, this opinion-based review provides a future insight into the management of renal anemia with HIF stabilizer by reference to the past experiences with ESA. HIF stabilizers can preferably be indicated for CRA syndrome at pre-dialysis stage, ESA resistant anemia at advanced CKD stage, and perhaps for dysregulated iron metabolism akin to MIA syndrome in patients on dialysis.

Peritoneal Dialysis in Patients with Diabetes: Are the Benefits Greater than the Disadvantages?

Diabetic nephropathy has been increasing in prevalence in recent years, and it is now the dominant cause of end-stage renal disease (ESRD) worldwide. Because diabetes is frequently associated with multiple complications, nephrologists must be alert to the selection of dialysis modality so as to reduce the accompanying risks. The present review addresses whether the benefits of peritoneal dialysis are greater than its disadvantages in diabetic patients. The answer is quite positive: for most diabetic patients, peritoneal dialysis offers multiple benefits.

Maternal psychological distress during and after pregnancy and atopic dermatitis in children

Background

Previous studies reported the association between maternal psychological distress (PD) during or after pregnancy and atopic dermatitis in children. However, studies examining the association from both pre- and post-natal aspects are limited.

Methods

We analysed data from 6,366 mother-child pairs who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study in Japan. Mothers were categorised into four groups of PD (K6 scores ≥5) during early pregnancy and one year after delivery; no PD in both periods, prenatal PD only, postnatal PD only, and PD in both periods. Mothers reported on their children's atopic dermatitis at age two using the International Study of Asthma and Allergies in Childhood (ISAAC). Multivariate logistic regression analysis was conducted to examine the association between maternal PD and atopic dermatitis in children adjusting for maternal age at delivery, maternal education, maternal smoking during early pregnancy, maternal history of atopic diseases, paternal history of atopic diseases, preterm birth, parity, and child's sex.

Results

The study population included 51.9% without PD in both periods, 14.6% with prenatal PD only, 14.0% with postnatal PD only, and 19.4% with PD in both periods. The prevalence of atopic dermatitis in children at age two was 18.8%. Mothers with postnatal PD only and mothers with PD in both periods had higher risks of children's atopic dermatitis compared with mothers without PD in both periods; the adjusted odds ratios (95% confidence intervals) were 1.37 (1.14-1.65) and 1.38 (1.17-1.63), respectively. The corresponding odds ratio (95% confidence interval) of mothers with prenatal PD only was 1.08 (0.89-1.31).

Conclusions

Postnatal PD was associated with an increased risk of atopic dermatitis in children. This finding suggests the importance for monitoring mental health among postpartum women.

Key messages

Postnatal PD has significant effects on atopic dermatitis in children. This study is a first study to examine the association between maternal PD and children’s atopic dermatitis in Japan. Improvements of postnatal care including social support might be effective in preventing atopic dermatitis in children.

Searching for the Reasons for Drop-Out from Peritoneal Dialysis: A Nationwide Survey in Japan

Purpose

We wanted to clarify, in a large population, the reasons that peritoneal dialysis (PD) was interrupted and to propose appropriate strategies that might prolong the use of PD as a renal replacement therapy.

Patients and Methods

We enrolled 5 391 patients from 439 centers into the study. Each center used a worksheet to report details about patients who either transferred to hemodialysis (HD) or died on continuous ambulatory peritoneal dialysis (CAPD) over a 6-month period from 1 April 2000, to 30 September 2000.

Results

We collected 252 drop-out cases from 141 centers. Of the 252 cases, 170 (67.5%) involved transfer to HD, and 82 (32.5%) involved death while on PD. Primary renal diseases were chronic nephritis (CN: 51.6%), diabetic nephropathy (DM: 26.6%), nephrosclerosis (4%), and unspecified or other condition (15.8%). Mean duration on PD in drop-out cases was 4.47 years. The age of patients at transfer to HD was younger (53.7 years) than the age of patients at death on PD (65.2 years). Patients with CN remained on PD significantly longer than did patients with DM (5 years vs 2.4 years). The three main reasons for PD discontinuation were overhydration because of ultrafiltration failure (UFF) or poor compliance with salt and fluid restrictions (34.1%); peritonitis (30.1%); and preference of the physician, patient, or family (6.5%). The proportional share represented by those three major reasons varied with the number of years since PD initiation (from 1 year to more than 8 years). Patients who had been on PD for a longer time were more likely to drop out because of UFF and less likely to drop out because of peritonitis. The three major causes of death on CAPD were cerebrovascular accident (22%), ischemic heart disease (14.6%), and sudden death (9.8%).

Conclusion

Approximately 10% of patients drop out from PD programs annually in Japan. To prolong PD treatment, new solutions that better preserve peritoneal function need to be developed, and patients and caregivers alike need to receive intensive education in preventing and treating peritonitis.

Tranexamic Acid Increases Peritoneal Ultrafiltration Volume in Patients on Capd

Objective

The preservation of ultrafiltration (UF) capacity is crucial to maintaining long-term continuous ambulatory peritoneal dialysis (CAPD). The aim of the present study was to investigate whether the antiplasmin agent tranexamic acid (TNA) increases UF volume in CAPD patients.

Patients and Methods

Fifteen patients on CAPD, 5 with UF loss and 10 without UF loss, were recruited for the study. The effect of TNA was evaluated with respect to changes in UF volume, peritoneal permeability, peritoneal clearance, bradykinin (BK), and tissue plasminogen activator (tPA) concentration.

Setting

Dialysis unit of the Saiseikai Central Hospital.

Results

In patients with UF loss, 2 weeks of treatment with oral TNA produced a significant increase in UF volume in all subjects (5/5). TNA also produced a significant increase in peritoneal clearances of urea and creatinine (Cr). However, the peritoneal equilibration test (PET) revealed that TNA had no effect on dialysate/plasma (D/P) Cr, Kt/V, or the protein catabolic rate (PCR). TNA also had no effect on net glucose reabsorption. In contrast, significant decreases in BK and blood tPA concentrations in response to TNA treatment were noted. BK concentration in drainage fluid was also reduced. In the case of patients without UF loss, TNA produced an increase in UF volume in 70% (7/10). However, no differences were found in blood and drainage BK and tPA concentrations between the TNA treatment and nontreatment periods in these patients. A comparison of basal BK and tPA concentration showed that there were no differences in these parameters between patients with UF loss and those without loss of UF. Furthermore, TNA given intraperitoneally to a patient also produced a marked increase in UF volume.

Conclusion

The present study suggests that TNA enhances UF volume in patients both with and without UF loss. Since TNA did not affect peritoneal permeability and glucose reabsorption, the mechanism by which TNA exerts an enhancing action on UF is largely unknown. We speculate that it may be associated with suppression of the BK and/or tPA system, at least in patients with UF loss.

Correction to: Dotinurad: a novel selective urate reabsorption inhibitor as a future therapeutic option for hyperuricemia

In the original publication of the article the presentation of Table 1 was incorrectly published.

Maternal dietary patterns during early pregnancy and birth weight in Japan

Background

The average birth weight in Japan has decreased by 200 g in the last 40 years. Only three studies were reported for the association between maternal dietary patterns and birth weight in East Asia, whose results were inconsistent. We examined what maternal dietary patterns were associated with the birth weight in Japan.

Methods

Totally 22,493 pregnant women were recruited between July 2013 and September 2016 into the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study. We included 17,287 women who had a full-term single healthy baby into the analysis. Consumption of food and beverage items was evaluated based on food frequency questionnaire at the first-trimester. Dietary patterns were analyzed using a machine learning method of k-means clustering algorithm. Birth weight was obtained from the medical record. The association between dietary patterns and birth weight was analyzed using multiple liner regression model adjusted for potential confounders with multiple imputation method for missing values.

Results

Dietary patterns were classified into seven groups by cluster analysis: “high in rice (reference) (n = 8046)”, “middle in vegetables, beans, mushrooms, seaweeds and miso-soup (n = 4842)”, “high in fruits (n = 1176)”, “high in bread, dairy and alcohol (n = 1091)”, “high in meat and fish (n = 1049)”, “high in coffee, black tea, soft drinks and confections (high in coffee) (n = 585)”, and “high in vegetables, beans, mushrooms, seaweeds and miso-soup (n = 498)” groups. In multiple liner regression models, birth weight was 22.6 g (95%CI: 0.1 to 45.2 g) heavier in “high in fruits” group than in reference group and 39.4 g (95%CI: 8.6 to 70.3 g) lighter in “high in coffee” group than in reference group. The other groups were not statistically significant.

Conclusions

High consumption of fruits and high consumption of coffee, black tea, soft drinks and confections during early pregnancy were associated with increased and decreased birth weight, respectively.

Key messages

We found maternal dietary patterns during early pregnancy using a machine learning method of k-means clustering algorithm. We found maternal dietary patterns which associated with the birth weight in Japan.

A Potential Mechanism of Cardio-Renal Protection with Sodium-Glucose Cotransporter 2 Inhibitors: Amelioration of Renal Congestion

Background: This review considers anew the etiology of the cardio-renal protective effect of sodium-glucose cotransporter 2 (SGLT2) inhibitors by extending the discussion to renal congestion, inherent in diabetic kidney disease (DKD) even at an early stage of nephropathy in which heart failure (HF) or salt and water accumulation is asymptomatic. Summary: The interstitial fluid (IF) space of the kidney space plays a crucial role for tubulointerstitial inflammation, renal hypoxia, and ischemic injury, which often leads to renal progression. In DKD, as a result of hyperglycemic milieu, excessive salt and water can be accumulated in the IF space, creating renal congestion. I hypothesize that SGLT2 inhibitors cause a shift in extracellular water from the IF space to the intravascular space to compensate for the SGLT2 inhibitor-induced hypovolemia. This decrease in IF volume ameliorates the IF space milieu and may reduce inflammation, hypoxia, and ischemic injury. Message: The present review proposes a novel theory; unlike other hypoglycemic agents or diuretics, SGLT2 inhibitor could protect DKD from failing by improving latent renal congestion even without symptomatic HF.

Effect of tibial component alignment on knee kinematics and ligament tension in medial unicompartmental knee arthroplasty

Objectives

Unicompartmental knee arthroplasty (UKA) is one surgical option for treating symptomatic medial osteoarthritis. Clinical studies have shown the functional benefits of UKA; however, the optimal alignment of the tibial component is still debated. The purpose of this study was to evaluate the effects of tibial coronal and sagittal plane alignment in UKA on knee kinematics and cruciate ligament tension, using a musculoskeletal computer simulation.

Methods

The tibial component was first aligned perpendicular to the mechanical axis of the tibia, with a 7° posterior slope (basic model). Subsequently, coronal and sagittal plane alignments were changed in a simulation programme. Kinematics and cruciate ligament tensions were simulated during weight-bearing deep knee bend and gait motions. Translation was defined as the distance between the most medial and the most lateral femoral positions throughout the cycle.

Results

The femur was positioned more medially relative to the tibia, with increasing varus alignment of the tibial component. Medial/lateral (ML) translation was smallest in the 2° varus model. A greater posterior slope posteriorized the medial condyle and increased anterior cruciate ligament (ACL) tension. ML translation was increased in the > 7° posterior slope model and the 0° model.

Conclusion

The current study suggests that the preferred tibial component alignment is between neutral and 2° varus in the coronal plane, and between 3° and 7° posterior slope in the sagittal plane. Varus > 4° or valgus alignment and excessive posterior slope caused excessive ML translation, which could be related to feelings of instability and could potentially have negative effects on clinical outcomes and implant durability.

Cite this article: K. Sekiguchi, S. Nakamura, S. Kuriyama, K. Nishitani, H. Ito, Y. Tanaka, M. Watanabe, S. Matsuda. Bone Joint Res 2019;8:126–135. DOI: 10.1302/2046-3758.83.BJR-2018-0208.R2.

Effectiveness of a fixed combination formula of ombitasvir/paritaprevir/ritonavir for hepatitis C virus infection in patients on maintenance haemodialysis

A fixed-dose formula that combines Ombitasvir (OBV), Paritaprevir (PTV) and Ritonavir (RTV) has been launched into the field of anti-HCV therapy in Japan for patients infected with HCV genotypes 1 and 2 in 2015. However, little is yet known as to the efficacy and safety of this novel therapy in patients on maintenance haemodialysis (HD). The present report describes a preliminary experience in 10 patients (five males and five females) who underwent maintenance HD. All of them had HCV genotype 1b, without having the resistance-associated variants at Y93 or L31 in the nonstructural proteins 5A (NS5A) region. After the treatment, eight patients successfully achieved virus eradication and sustained a virological response at 12 weeks (SVR12). In addition, mac-2 binding protein glycosylation isomer (M2BPGi), a biomarker for liver fibrosis, was reduced after the therapy. Two patients withdrew from the therapy due to the development of erythema multiforme and a strong drowsiness, respectively. These results suggest that triple therapy combining OBV, PTV and RTV is effective in achieving SVR12 in most of the HCV-infected patients on HD. In addition, this combination therapy contributed to retard the progression of liver fibrosis. However, we suggest that further trial will be required to establish its clinical efficacy and safety.

The effects of kinematically aligned total knee arthroplasty on stress at the medial tibia: A case study for varus knee

OBJECTIVES

Little biomechanical information is available about kinematically aligned (KA) total knee arthroplasty (TKA). The purpose of this study was to simulate the kinematics and kinetics after KA TKA and mechanically aligned (MA) TKA with four different limb alignments.

MATERIALS AND METHODS

Bone models were constructed from one volunteer (normal) and three patients with three different knee deformities (slight, moderate and severe varus). A dynamic musculoskeletal modelling system was used to analyse the kinematics and the tibiofemoral contact force. The contact stress on the tibial insert, and the stress to the resection surface and medial tibial cortex were examined by using finite element analysis.

RESULTS

In all bone models, posterior translation on the lateral side and external rotation in the KA TKA models were greater than in the MA TKA models. The tibiofemoral force at the medial side was increased in the moderate and severe varus models with KA TKA. In the severe varus model with KA TKA, the contact stress on the tibial insert and the stress to the resection surface and to the medial tibial cortex were increased by 41.5%, 32.2% and 53.7%, respectively, compared with MA TKA, and the bone strain at the medial side was highest among all models.

CONCLUSION

Near normal kinematics was observed in KA TKA. However, KA TKA increased the contact force, stress and bone strain at the medial side for moderate and severe varus knee models. The application of KA TKA for severe varus knees may be inadequate.Cite this article: S. Nakamura, Y. Tian, Y. Tanaka, S. Kuriyama, H. Ito, M. Furu, S. Matsuda. The effects of kinematically aligned total knee arthroplasty on stress at the medial tibia: A case study for varus knee. Bone Joint Res 2017;6:43-51. DOI: 10.1302/2046-3758.61.BJR-2016-0090.R1.

Combined therapy with peritoneal dialysis and hemodialysis: a multicenter retrospective observational cohort study in Japan

BACKGROUND/AIMS

Combining peritoneal dialysis (PD) and hemodialysis (HD) has been common treatment option in Japan.

METHODS

In this retrospective, multicenter, observational study, the clinical characteristics and outcomes of 104 patients (57 ± 11 years, males 72%) who had switched from PD alone to combined therapy with PD and HD were studied. Clinical parameters were measured at baseline and after 3 months of combined therapy.

RESULTS

At baseline, urine volume, dialysate-to-plasma ratio of creatinine (D/P Cr), and total Kt/V were 150 ml/day (range: 0-2,000 ml/day), 0.67 ± 0.11, and 1.8 ± 0.4, respectively. During the first 3 months of combined therapy, body weight, urine volume, serum creatinine level, and D/P Cr decreased, whereas hemoglobin levels increased.

CONCLUSIONS

In patients where PD does not result in acceptable outcomes, combined therapy with PD and HD may have potential benefits in terms of dialysis adequacy and hydration status. Video Journal Club “Cappuccino with Claudio Ronco” at http://www.karger.com/?doi=368389

Asporin activates coordinated invasion of scirrhous gastric cancer and cancer-associated fibroblasts

Scirrhous gastric cancer, which has the worst prognosis among the various types of gastric cancer, is highly invasive and associated with abundant stromal fibroblasts. Although cancer-associated fibroblasts (CAFs) have been proposed to generate a tumor-supportive extracellular matrix that promotes the expansion of this type of cancer, the molecular mechanisms by which CAFs assist cancer cells are not yet fully understood. Here, we show for the first time that Asporin, a small leucine-rich proteoglycan (SLRP), is predominantly expressed in CAFs, and has essential roles in promoting co-invasion of CAFs and cancer cells. CAFs of scirrhous gastric cancer possess high potential for invasion, and invasion by CAFs frequently proceeded invasion by cancer cells, both in vitro and in vivo. Expression of Asporin was induced in fibroblasts by exposure to gastric cancer cells. Asporin secreted from CAFs activates Rac1 via an interaction with CD44 and promotes invasion by CAFs themselves. Moreover, Asporin promoted invasion by neighboring cancer cells, via paracrine effects mediated by activation of the CD44-Rac1 pathway. These results suggest that Asporin is a unique SLRP that promotes progression of scirrhous gastric cancer and is required for coordinated invasion by CAFs and cancer cells. Therefore, Asporin may represent a new therapeutic target molecule for the development of drugs aimed at manipulating the cancer microenvironment.

[Relationship between serum uric acid levels and muscle strength/volume: a new insight from a large-scale survey]

AIM

Serum uric acid (UA) concentration is regulated by its production in the liver and/or intestine and its rate of excretion from the kidneys. However, little is known about skeletal muscle involvement in determining the physiological UA level. The present trial explores whether muscle strength and/or muscle volume is associated with UA levels.

MATERIAL & METHODS

Muscle strength was evaluated in terms of grasping power calculated as an average of right and left hand measurements in relation to other parameters in 14,333 subjects (median age; 41.2 years), who were recruited to the study. Skeletal muscle volume was calculated based on the bioimpedance method by subtracting estimated fat volume plus estimated bone weight from the total body weight.

RESULTS

1) Multiple regression analyses to explain the association with UA levels (dependent variable) revealed that BMI, BUN, triglyceride, muscle strength, AST, age and sex are independent variables. 2) Higher UA levels (assessed as 4 UA quartiles) are associated with higher muscle volume, muscle strength, BMI, DBP, and serum creatinine (Cr) concentration. 3) Greater DBP (assessed as 2 UA categories) was associated with higher BMI, muscle strength, muscle volume, UA levels and serum Cr concentration. 4) Regression coefficient "t" for muscle strength was the largest among the other parameters including serum Cr concentration in the UA level ranging from 5.5 to 6.5 mg/dL.

CONCLUSION

There was an association between muscle strength/volume and UA levels in the near physiological UA range, suggesting that the circulating UA levels can be, at least in part, controlled by its production in the skeletal muscles.

Severe hyponatremia caused by secondary adrenal insufficiency in a patient with giant pituitary prolactinoma

A 55-year-old-man was admitted to Saiseikai Central Hospital, Tokyo, Japan, complaining of nausea and appetite loss, and was found to have severe hyponatremia. Despite severe hyponatremia and plasma hypo-osmolarity, urinary sodium excretion was not reduced. A brain magnetic resonance imaging (MRI) scan revealed a giant pituitary prolactinoma, and endocrinological tests showed a markedly increased prolactin level. Despite the observation that the basal plasma ACTH level was normal, serum cortisol and urinary cortisol excretion levels were low. Rapid ACTH loading sufficiently stimulated an increase in serum cortisol levels, suggesting secondary adrenal insufficiency. Notably, loading of CRH induced a good ACTH response; however, the serum cortisol response remained low. In contrast, the continuous daily administration of exogenous ACTH dramatically increased serum cortisol levels. These discrepant responses may have been caused by the low biological activity of innate ACTH. Following partial resection of the prolactinoma, postoperative adjuvant therapy with cabergoline effectively reduced prolactin levels, but did not improve the hyponatremia. In contrast, hydrocortisone replacement therapy recovered the serum sodium level to the normal range. The present case is the first report describing a link between severe hyponatremia and biologically inactive circulating ACTH as a likely result of giant prolactinoma.

PP083. Clinic and out-of-clinic blood pressure changes during pregnancy by parity: Boshi study

INTRODUCTION

Nulliparity is believed to be one of the risk factors for hypertension during pregnancy. However, the relationship between parity and out-of-clinic blood pressure during pregnancy is still unknown.

OBJECTIVES

The aim of this study was to evaluate clinic blood pressure and blood pressure measured at home during pregnancy among nulliparous and multiparous women.

METHODS

This study was a prospective cohort study. We examined blood pressure measured in the clinic and at home among 530 normotensive pregnant women who received antenatal care at a maternity hospital in Japan. Clinic blood pressures were obtained by duplicate measurements at each antenatal care visit. The participants were also required to measure their own blood pressures every morning at home while they were pregnant. A linear mixed model was used for analysis of the blood pressure course throughout pregnancy [1]. The SAS package (version 9.2) was used for the statistical analyses.

RESULTS

A total of 315 nulliparous and 215 multiparous women were entered into this study (mean ages 30.1±4.6years and 33.0±4.1years, respectively). Clinic blood pressure during pregnancy among nulliparous women was significantly higher than that among multiparous women (P=0.02/P<0.0001 for systolic/diastolic blood pressure), whereas there were no significant differences in blood pressure measured at home during pregnancy between them (P=0.42/P=0.22 for systolic/diastolic blood pressure).

CONCLUSION

Out-of-clinic blood pressure levels during pregnancy have been shown not to differ between nulliparous and multiparous women, while clinic blood pressure during pregnancy among nulliparous women is higher than that among multiparous women.

Antihypertensive effect of a fixed-dose combination of losartan/hydrochlorothiazide in patients with uncontrolled hypertension: a multicenter study

BACKGROUND

Achieving adequate blood pressure (BP) control often requires more than one antihypertensive agent. The purpose of this study was to determine whether a fixed-dose formulation of losartan (LOS) plus hydrochlorothiazide (HCTZ) (LOS/HCTZ) is effective in achieving a greater BP lowering in patients with uncontrolled hypertension.

METHODS

The study was a prospective, multicenter, observational trial exploring the antihypertensive effect of a single tablet of LOS 50 mg/HCTZ 12.5 mg. A total of 228 patients whose BP had previously been treated with more than one antihypertensive agents without having achieved BP goal below 130/80 mmHg enrolled in the study.

RESULTS

A significant decrease in systolic and diastolic BP was observed in both clinic and home measurement after switching from the previous treatment to LOS/HCTZ. There was a significant decrease in both B-type natriuretic peptide (BNP) and urinary albumin creatinine (Cr) excretion ratio (ACR), especially in patients with elevated values. In contrast, there was a significant increase in serum Cr concentration in conjunction with a decrease in estimated glomerular filtration rate (eGFR). Overall serum uric acid (UA) concentration increased, whereas in patients with hyperuricemia there was a significant reduction in this value.

CONCLUSION

Switching to LOS/HCTZ provides a greater reduction in clinic and home BP in patients with uncontrolled hypertension. This combination therapy may lead to cardio-, reno protection and improve UA metabolism.

Effects of combined antihypertensive therapy with losartan/hydrochlorothiazide on uric acid metabolism

OBJECTIVE

The Jikei Optimal Antihypertensive Treatment (JOINT) study originally evaluated the effect of a fixed-dose formulation of losartan (LOS) (50 mg) plus 12.5 hydrochrolthiazide (HCTZ) for achieving better blood pressure (BP) control in patients with uncontrolled hypertension. This study is a sub-analysis of the JOINT study, focusing on the effect of LOS/HCTZ on the uric acid (UA) metabolism.

METHODS

Among 228 participants in the JOINT study, a total of 164 patients whose blood and urinary UA specimens were available were included in the present analyses.

RESULTS

Six months after switching from the prior antihypertensive agent(s) to a single tablet formulation of LOS/HCTZ, the overall serum UA concentration (sUA) increased from 6.0 ± 1.6 mg/dL to 6.2 ± 1.6 mg/dL (p=0.029). The urinary UA/creatinine (Cr) ratio increased from 0.45 +/- 0.21 to 0.50 +/- 0.25 (p=0.014), and the fractional excretion of UA (FEUA) also increased, from 7.1 +/- 3.6 to 7.0 +/- 4.3, p=0.04). Multivariate regression analyses of the basal parameters showed the change in sUA (ΔUA) to correlate with the basal sUA (β=-0.483, p<0.001), estimated glomerular filtration rate (eGFR) (β=-0.202, p=0.007) and systolic BP (β=0.147, p=0.038). In addition, the ΔUA also correlated with the changes in the estimated glomerular filtration rate (ΔeGFR) (β=-0.332, p<0.001). When the patients were classified into two groups depending on their basal sUA, those with a basal sUA ≥ 7 mg/dL exhibited a decrease in their sUA, whereas the rest of those with a sUA <7 mg/dL experienced an increase. Furthermore, patients who had previously been treated with LOS alone had a greater increase in the sUA than those treated with an angiotensin II blocker (ARB) other than LOS alone.

CONCLUSION

Antihypertensive therapy with a single tablet formulation of LOS/HCTZ is considered to be a useful option for controlling both BP and sUA, especially in uncontrolled hypertensive patients with hyperuricemia.

[Study on the predictors for superimposed preeclampsia in patients with IgA nephropathy]

OBJECTIVE

Pregnancy in chronic kidney disease (CKD) patients is often associated with hypertension and/or the worsening of renal function and neonatal death. The present study explored the clinical characteristics of predictive factors for hypertension in biopsy-proven IgA nephropathy patients with superimposed preeclampsia (SPE).

PATIENTS AND METHODS

The subjects were 34 Japanese women with IgA nephropathy whose renal specimen for histological tests was obtained before pregnancy. We retrospectively investigated the relevant clinical factors to explain a rise in blood pressure (BP). The histological findings were evaluated with respect to the quantitative measurements of both global glomerulosclerosis and interstitial damage.

RESULTS

Renal biopsies before pregnancies showed that the global glomerular sclerosing index and interstitial damage in the SPE group were significantly higher than in the normal group. The prevalence of SPE was 38.2 % (normal pregnancy 21, SPE 13 cases). The neonatal death rate was 3.0 % (1/34)overall. Just before conception, systolic blood pressure (SBP), serum creatinine (Cr)and blood urea nitrogen (BUN) concentration in the SPE were significantly higher than in normal pregnancies. In contrast, CCr and eGFR were lower in the SPE group than in the normal group. At delivery, serum Cr, BUN and uric acid (UA) concentration in the SPE group were significantly higher than in the normal group. In contrast, CCr and eGFR were lower in the SPE than in the normal group. At delivery, correlation analysis revealed a significant correlation between SBP or diastolic BP (DBP) and the histological severity, between SBP or DBP and daily protein excretion, and between SBP or DBP and serum Cr concentration. With respect to the birth weight of newborns, there was a significant negative correlation between the birth weight and the global glomerular sclerosing rate, and between the birth weight and serum Cr concentration or BUN. A stepwise multiple regression analysis showed that predictive factors for a rise in SBP during pregnancy were the degree of interstitial damage and daily urinary protein excretion. These results suggest that renal function, the magnitude of urinary protein excretion, serum Cr, BUN, UA concentrations, and the severity of histological abnormalities are all associated with SPE occurrence. The predictors of a rise in BP were interstitial damage and urinary protein excretion at pregnancy. In addition, Receiver Operating Characteristic (ROC) analysis showed that both glomerular sclerosis and interstitial damage could be potential predictors for SPE.

CONCLUSION

Histological severity in renal biopsy, urinary protein excretion and renal function are associated with SPE in patients with IgA nephropathy. Among these associations, the histological findings and urinary protein excretion may serve as useful predictors for a rise in BP.

2008 Japanese Society for Dialysis Therapy: guidelines for renal anemia in chronic kidney disease

The Japanese Society for Dialysis Therapy (JSDT) guideline committee, chaired by Dr Y. Tsubakihara, presents the Japanese guidelines entitled "Guidelines for Renal Anemia in Chronic Kidney Disease." These guidelines replace the "2004 JSDT Guidelines for Renal Anemia in Chronic Hemodialysis Patients," and contain new, additional guidelines for peritoneal dialysis (PD), non-dialysis (ND), and pediatric chronic kidney disease (CKD) patients. Chapter 1 presents reference values for diagnosing anemia that are based on the most recent epidemiological data from the general Japanese population. In both men and women, hemoglobin (Hb) levels decrease along with an increase in age and the level for diagnosing anemia has been set at <13.5 g/dL in males and <11.5 g/dL in females. However, the guidelines explicitly state that the target Hb level in erythropoiesis stimulating agent (ESA) therapy is different to the anemia reference level. In addition, in defining renal anemia, the guidelines emphasize that the reduced production of erythropoietin (EPO) that is associated with renal disorders is the primary cause of renal anemia, and that renal anemia refers to a condition in which there is no increased production of EPO and serum EPO levels remain within the reference range for healthy individuals without anemia, irrespective of the glomerular filtration rate (GFR). In other words, renal anemia is clearly identified as an "endocrine disease." It is believed that defining renal anemia in this way will be extremely beneficial for ND patients exhibiting renal anemia despite having a high GFR. We have also emphasized that renal anemia may be treated not only with ESA therapy but also with appropriate iron supplementation and the improvement of anemia associated with chronic disease, which is associated with inflammation, and inadequate dialysis, another major cause of renal anemia. In Chapter 2, which discusses the target Hb levels in ESA therapy, the guidelines establish different target levels for hemodialysis (HD) patients than for PD and ND patients, for two reasons: (i) In Japanese HD patients, Hb levels following hemodialysis rise considerably above their previous levels because of ultrafiltration-induced hemoconcentration; and (ii) as noted in the 2004 guidelines, although 10 to 11 g/dL was optimal for long-term prognosis if the Hb level prior to the hemodialysis session in an HD patient had been established at the target level, it has been reported that, based on data accumulated on Japanese PD and ND patients, in patients without serious cardiovascular disease, higher levels have a cardiac or renal function protective effect, without any safety issues. Accordingly, the guidelines establish a target Hb level in PD and ND patients of 11 g/dL or more, and recommend 13 g/dL as the criterion for dose reduction/withdrawal. However, with the results of, for example, the CHOIR (Correction of Hemoglobin and Outcomes in Renal Insufficiency) study in mind, the guidelines establish an upper limit of 12 g/dL for patients with serious cardiovascular disease or patients for whom the attending physician determines high Hb levels would not be appropriate. Chapter 3 discusses the criteria for iron supplementation. The guidelines establish reference levels for iron supplementation in Japan that are lower than those established in the Western guidelines. This is because of concerns about long-term toxicity if the results of short-term studies conducted by Western manufacturers, in which an ESA cost-savings effect has been positioned as a primary endpoint, are too readily accepted. In other words, if the serum ferritin is <100 ng/mL and the transferrin saturation rate (TSAT) is <20%, then the criteria for iron supplementation will be met; if only one of these criteria is met, then iron supplementation should be considered unnecessary. Although there is a dearth of supporting evidence for these criteria, there are patients that have been surviving on hemodialysis in Japan for more than 40 years, and since there are approximately 20 000 patients who have been receiving hemodialysis for more than 20 years, which is a situation that is different from that in many other countries. As there are concerns about adverse reactions due to the overuse of iron preparations as well, we therefore adopted the expert opinion that evidence obtained from studies in which an ESA cost-savings effect had been positioned as the primary endpoint should not be accepted unquestioningly. In Chapter 4, which discusses ESA dosing regimens, and Chapter 5, which discusses poor response to ESAs, we gave priority to the usual doses that are listed in the package inserts of the ESAs that can be used in Japan. However, if the maximum dose of darbepoetin alfa that can currently be used in HD and PD patients were to be used, then the majority of poor responders would be rescued. Blood transfusions are discussed in Chapter 6. Blood transfusions are attributed to the difficulty of managing renal anemia not only in HD patients, but also in end-stage ND patients who respond poorly to ESAs. It is believed that the number of patients requiring transfusions could be reduced further if there were novel long-acting ESAs that could be used for ND patients. Chapter 7 discusses adverse reactions to ESA therapy. Of particular concern is the emergence and exacerbation of hypertension associated with rapid hematopoiesis due to ESA therapy. The treatment of renal anemia in pediatric CKD patients is discussed in Chapter 8; it is fundamentally the same as that in adults.

Adiposity, adult weight change and breast cancer risk in postmenopausal Japanese women: the Miyagi Cohort Study

Background:

The role of adult weight change in breast cancer (BC) risk is unclear in Japanese women.

Methods:

A total of 10 106 postmenopausal women aged 40–64 years (the Miyagi Cohort) were followed from 1990 to 2003, and 108 BC cases were identified. Hazard ratios (HRs) were estimated according to body mass index (BMI) at the current age and at the of age 20 years, and weight change since age 20 years.

Results:

Higher current BMI was associated with an increased risk of BC (P for trend=0.02), whereas higher BMI at the age 20 years was inversely associated with this risk (P for trend=0.002). There was a significant association between weight change since age 20 years and BC risk (P for trend=0.0086). Compared with stable weight, HR was 0.35 for weight loss of 5 kg or more (P for weight loss trend=0.04) and 1.55 for weight gain of 12 kg or more (P for weight gain trend=0.05).

Conclusion:

Adiposity at younger and current age has differential effects on BC risk among postmenopausal women; weight gain in adulthood being associated with an increased, and weight loss with a decreased risk.

Texture synthesis for mobile data communications

This paper presents an approach to image coding that first paints a regularly arranged dotted pattern, using colors picked from a texture sample with features corresponding to the embedded data. It then camouflages the dotted pattern using the same texture sample while preserving quality comparable to that of existing synthesis techniques.

Quality of life of patients and medical cost of "half elemental diet" as maintenance therapy for Crohn's disease: secondary outcomes of a randomised controlled trial

BACKGROUND/AIM

Quality of life (QOL) of the patients and medical costs are important in current medical treatments, especially those for chronic diseases. We have reported the effectiveness of 'half elemental diet (ED)' as maintenance therapy for patients with Crohn's disease (CD). The aim of this study was to evaluate the QOL of CD patients and medical costs of half-ED.

METHODS

Fifty-one CD patients in remission were randomly assigned to a half-ED group (n=26) or a free diet group (n=25). The primary outcome measure was the occurrence of relapse during a 2-year period. This time, we investigated the QOL of the patients and medical costs of half-ED, as secondary outcomes. QOL was evaluated using the Japanese version of the IBDQ scoring system, and medical costs were calculated monthly from the receipts.

RESULTS

IBDQ score was not significantly different between the two groups at 1 and 13 months after the start of maintenance treatment. Medical costs were not significantly different between them either. This study showed that half-ED therapy did not affect the treatment of CD patients, neither regarding their QOL nor medical costs.

CONCLUSION

This study has confirmed this half-ED therapy is beneficial for patients with Crohn's disease.

Sleep duration and the risk of breast cancer: the Ohsaki Cohort Study

In a prospective study of 23 995 Japanese women, short sleep duration was associated with higher risk of breast cancer (143 cases), compared with women who slept 7 h per day, the multivariate hazard ratio of those who slept ⩽6 h per day was 1.62 (95% confidence interval: 1.05–2.50; P for trend=0.03).

Green tea consumption and lung cancer risk: the Ohsaki study

We examined the risk of lung cancer in relation to green tea consumption in a population-based cohort study in Japan among 41 440 men and women, aged 40–79 years, who completed a questionnaire in 1994 regarding green tea consumption and other health-related lifestyle factors. During the follow-up period of 7 years (from 1995 to 2001), 302 cases of lung cancer were identified, and the Cox proportional hazards regression model was used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs). The multivariable-adjusted HRs of lung cancer incidence for green tea consumption of 1 or 2, 3 or 4, and 5 or more cups/day as compared to less than 1 cup/day were 1.14 (95% CI: 0.80–1.62), 1.18 (95% CI: 0.83–1.66), and 1.17 (95% CI: 0.85–1.61), respectively (P for trend=0.48). This cohort study has found no evidence that green tea consumption is associated with lung cancer.

Outcomes of 23- and 25-gauge transconjunctival sutureless vitrectomies for idiopathic macular holes

BACKGROUND/AIMS

To assess the outcomes of 23-gauge sutureless transconjunctival vitrectomies (TSV), as compared with 25-gauge TSV in macular hole surgeries.

METHODS

A retrospective, consecutive, interventional case series of 47 eyes with idiopathic macular holes treated by 23- or 25-gauge TSV were analysed.

RESULTS

The operative time was 37.2 (SD 8.9) min with 23-gauge TSV and 34.2 (8.7) min with 25-gauge TSV (p = 0.388). The anatomical success rate was 96% with 23-gauge TSV and 92% with 25-gauge TSV (p>0.999). The logarithm of the minimum angle of resolution of best-corrected visual acuity (BCVA) at the sixth postoperative month was 0.19 (0.16) with 23-gauge TSV and 0.19 (0.25) with 25-gauge TSV (p = 0.521). Postoperative improvement in BCVA was comparable between the two TSVs. IOP on postoperative day 1 was lower with 25-gauge TSV (12.3 (4.9) mm Hg) than with 23-gauge TSV (17.4 (5.8) mm Hg) (p = 0.036). Complications included retinal break, intraoperative bleeding and slippage of the infusion cannula with 23-gauge TSV, while retinal detachment and postoperative hypotony occurred in the 25-gauge TSV group (p = 0.570).

CONCLUSION

23-gauge TSV appears to be as safe and effective as 25-gauge TSV in macular hole surgery.

Sleep duration and the risk of prostate cancer: the Ohsaki Cohort Study

In a prospective study of prostate cancer incidence (127 cases), among 22 320 Japanese men, sleep duration was associated with lower risk; the multivariate hazard ratio of men who slept ⩾9 h per day compared with those who slept less was 0.48 (95% confidence interval: 0.29–0.79, P for trend=0.02).

Effects of icodextrin on glycemic and lipid profiles in diabetic patients undergoing peritoneal dialysis

AIM

Icodextrin reduces glucose absorption from the peritoneal dialysate. We conducted this prospective, open-labeled, multicenter study to determine the effects of icodextrin on glycemic and lipid parameters in diabetic patients undergoing continuous ambulatory peritoneal dialysis (PD) or automated PD.

METHODS

Patients were recruited from 15 institutions in Japan, and a total of 51 patients (15 women and 36 men, mean age: 59 +/- 10 years, median duration of PD: 13 months) were enrolled. The patients were administered an overnight or daytime dwell of 1.5 or 2.0 l of 7.5% icodextrin-containing solution. At baseline and 3, 6, 9 and 12 months after the start of icodextrin, nonfasting blood was drawn for measurement of glycated hemoglobin (HbA1C) and serum lipids.

RESULTS

During icodextrin treatment, there was no change in overall HbA1C levels compared to baseline values; however, for those with baseline HbA1C > or =6.5% (n = 22), significant decreases in HbA1C were observed. Mean total/LDL cholesterol and triglycerides were decreased significantly during icodextrin treatment, with greater decreases for patients with baseline total cholesterol > or =220 mg/dl, LDL cholesterol > or =120 mg/dl or triglycerides > or =150 mg/dl. HDL cholesterol did not differ at any time point; however, values for patients with baseline HDL cholesterol <40 mg/dl tended to increase with marginal significance.

CONCLUSIONS

In the current study, switching from glucose-containing dialysis solution to icodextrin resulted in improved lipid profiles and possibly a favorable metabolic profile, particularly in patients with poor glycemic control. These hypotheses remain to be proven in controlled clinical trials.

Peritoneal dialysis in patients with diabetes: are the benefits greater than the disadvantages?

Diabetic nephropathy has been increasing in prevalence in recent years, and it is now the dominant cause of end-stage renal disease (ESRD) worldwide. Because diabetes is frequently associated with multiple complications, nephrologists must be alert to the selection of dialysis modality so as to reduce the accompanying risks. The present review addresses whether the benefits of peritoneal dialysis are greater than its disadvantages in diabetic patients. The answer is quite positive: for most diabetic patients, peritoneal dialysis offers multiple benefits.