Taxonomic characterization of Sphaerotilus microaerophilus sp. nov., a sheath-forming microaerophilic bacterium of activated sludge origin.

A microaerophilic Gram-stain-negative bacilliform bacterial strain, FB-5 T, was isolated from activated sludge in Yokohama, Japan, that exhibited filamentous growth and formed a microtube (sheath). Cells were motile using a single polar flagellum. The optimum growth temperature and pH were 30 °C and 7.5, respectively. Strain FB-5 T was catalase-negative. Peptides and amino acids were utilized as energy and carbon sources. Sugars and organic acids were not utilized. Vitamin B12 enhanced the growth of strain FB-5 T. Sulfur-dependent lithotrophic growth was possible. Major respiratory quinone was UQ-8. Major fatty acids were C16:1ω7 and C16:0. The genomic DNA G + C content was 69.16%. Phylogenetic analysis of the 16S rRNA gene suggested that strain FB-5 T belongs to the genus Sphaerotilus. The close relatives were S. natans subsup. sulfidivorans and S. natans subsup. natans with 98.0% and 97.8% similarity based on the 16S rRNA gene analysis, respectively. The genome size (6.06 Mbp) was larger than that (4.39-5.07 Mbp) of the Sphaerotilus strains. The AAI values against the related strains ranged from 71.0 to 72.5%. The range of ANI values was 81.7 - 82.5%. In addition to these distinguishable features of the genome, the core genome and dDDH analyses suggested that this strain is a novel member of the genus Sphaerotilus. Based on its physiological properties and genomic features, strain FB-5 T is considered as a novel species of the genus Sphaerotilus, for which the name S. microaerophilus sp. nov. is proposed. The type strain is FB-5 T (= JCM 35424 T = KACC 23146 T).

Effects of simultaneous pancreas and kidney transplantation in Japanese individuals with type 1 diabetes and end-stage kidney disease.

This single-center observational cohort study aimed to assess the potential benefits of simultaneous pancreas and kidney transplantation (SPK) in terms of mortality and kidney graft outcomes in Japanese individuals with type 1 diabetes (T1D) and end-stage kidney disease (ESKD). We first compared all-cause mortality rates between 78 SPK recipients and 108 non-transplanted individuals with T1D and ESKD. To mitigate the bias stemming from immortal time before receiving SPK, we utilized Cox regression models treating SPK as a time-dependent covariate. Next, we compared all-cause mortality rates and kidney graft loss rates between 65 SPK recipients and 58 kidney transplantation alone (KTA) recipients. Multivariate Cox hazard models and Fine and Gray competing-risk models were employed. SPK recipients experienced significantly lower all-cause mortality rates than non-transplanted individuals, even after accounting for immortal time bias (p = 0.015 by log-rank test, hazard ratio [HR] = 0.334, p = 0.025). When comparing SPK and KTA recipients, no statistically significant difference was observed in mortality rates (HR = 0.627, p = 0.588 by Cox model; HR = 0.385, p = 0.412 by Fine and Gray model) or kidney graft loss rates (HR = 0.612, p = 0.436 by Cox model; HR = 0.639, p = 0.376 by Fine and Gray model). Dysglycemia-associated mortality were observed in non-transplanted individuals and KTA recipients, but not in SPK recipients. These findings highlight the potential life-saving impact of SPK compared with intensive insulin therapy and dialysis. Additionally, this study suggests that both SPK and KTA may offer comparable outcomes. These findings have significant implications for clinical decision-making in the context of organ transplantation for individuals with T1D and ESKD.

Cardiac 18F­FDG uptake and new­onset rectal cancer.

The present study aimed to investigate the factors affecting the cardiac uptake of 18F-fluorodeoxyglucose (18F-FDG) during 18F-FDG positron emission tomography (PET) for new-onset rectal cancer and new-onset colon cancer (ascending, transverse, descending, sigmoid colon cancer) and to examine the association between the cardiac uptake of 18F-FDG and prognosis. The participants were diagnosed with new-onset rectal cancer and new-onset colon cancer (ascending, transverse, descending, sigmoid cancer) at the Iga City General Hospital (Iga, Japan) between January 1, 2013, and March 31, 2018, and underwent an 18F-FDG PET scan for pretreatment staging. The relationship between cardiac maximum standard uptake value (SUVmax), the presence/absence of distant metastasis and prognosis was examined. A total of 26 patients (14 men and 12 women) aged 72.0±10 years with new-onset rectal cancer were selected for the study. No patients had multiple simultaneous cancers. The median cardiac SUVmax was 3.8 and 2.5 in patients with no distant metastasis and distant metastasis, respectively, revealing a statistically significant difference (P<0.01). The median tumor volume on PET-computed tomography (CT) images was 7,815 cm2 and was 66,248 cm2 in patients with no distant metastasis and distant metastasis, respectively, revealing a statistically significant difference (P<0.01). Echocardiography findings revealed no significant difference between patients with and without distant metastasis. The correlation coefficient between cardiac SUVmax and total tumor volume on PET/CT images (primary + lymph + distant metastases) was statistically significant (r=-0.42, P=0.03). Analysis of the association between the occurrence of distance metastasis and cardiac SUVmax as a continuous variable gave a statistically significant result [hazard ratio (HR): 0.30, 95% confidence interval (CI): 0.09-0.98, P=0.045]. Receiver operating characteristic analysis showed a cardiac SUVmax of 2.6 with an area under the curve of 0.86 for determining the presence of distant metastasis (95% CI: 0.70-1.00). The median observation time was 56 months, and nine patients died during observation. Analysis of the association between the overall survival and cardiac SUVmax (cutoff: 2.6) showed 95% CI: 0.01-0.45 and HR: 0.06 (P<0.01); that between the overall survival and total tumor volume on PET images showed 95% CI: 1.00-1.00 and HR: 1.00 (P<0.01); and that between the overall survival and presence of distant metastasis showed 95% CI: 1.72-116.4 and HR: 14.1 (P<0.01). Furthermore, 25 patients (16 men and nine women) aged 71.4±14.2 years with new-onset colon cancer were selected for the study. Analysis of new-onset colon cancer revealed no statistically significance between the cardiac SUVmax and distant metastasis.

Changes in urinary albumin as a surrogate for kidney disease progression in people with type 2 diabetes.

BACKGROUND: It remains unclear whether urinary albumin changes can predict subsequent kidney disease progression in people with diabetes. METHODS: This retrospective cohort study included 4570 Japanese adults with type 2 diabetes (T2D). The exposure was changes in urinary albumin-to-creatinine ratio (UACR) over 3 years, categorized into three categories: ≤ - 30%, minor change, or ≥ 30%. During the exposure period, eGFR decline was also examined and categorized into two categories: < 30% or ≥ 30% decline. The primary outcome was the composite of eGFR halving or initiation of kidney replacement therapy (KRT). The secondary outcome was the initiation of KRT. RESULTS: In the spline model, the hazard ratio for the primary outcome increased linearly on the log2 scale of UACR changes. When classified into six groups based on the categories of UACR changes and eGFR decline, people with a ≤ - 30% UACR change and < 30% eGFR decline had a 38% lower incidence of the outcome compared to those with a minor UACR change and < 30% eGFR decline. Meanwhile, the risk in those with a ≤ - 30% UACR change and ≥ 30% eGFR decline was 2.89 times. People with a ≥ 30% UACR change had the higher risk, regardless of whether a ≥ 30% eGFR decline occurred. Similar results were obtained in the secondary outcome. CONCLUSIONS: UACR changes can be a useful surrogate for kidney disease progression in people with T2D. However, when setting a decrease in UACR as the surrogate, it may be necessary to simultaneously evaluate kidney function decline.

A heterodimeric hyaluronate lyase secreted by the activated sludge bacterium Haliscomenobacter hydrossis.

Haliscomenobacter hydrossis is a filamentous bacterium common in activated sludge. The bacterium was found to utilize hyaluronic acid, and hyaluronate lyase activity was detected in its culture. However, no hyaluronate lyase gene was found in the genome, suggesting the bacterium secretes a novel hyaluronate lyase. The purified enzyme exhibited two bands on SDS-PAGE and a single peak on gel filtration chromatography, suggesting a heterodimeric composition. N-terminal amino acid sequence and mass spectrometric analyses suggested that the subunits are molybdopterin-binding and [2Fe-2S]-binding subunits of a xanthine oxidase family protein. The presence of the cofactors was confirmed using spectrometric analysis. Oxidase activity was not detected, revealing that the enzyme is not an oxidase but a hyaluronate lyase. Nuclear magnetic resonance analysis of the enzymatic digest revealed that the enzyme breaks hyaluronic acid to 3-(4-deoxy-ß-d-gluc-4-enuronosyl)-N-acetyl-d-glucosamine. As hyaluronate lyases (EC 4.2.2.1) are monomeric or trimeric, the enzyme is the first heterodimeric hyaluronate lyase.

Association of Estimated Glomerular Filtration Rate With Progression of Albuminuria in Individuals With Type 2 Diabetes.

OBJECTIVE: To elucidate the association of glomerular filtration rate (GFR) at baseline with subsequent progression of albuminuria in individuals with type 2 diabetes. RESEARCH DESIGN AND METHODS: This was a single-center retrospective cohort study of 6,618 Japanese adults with type 2 diabetes and urinary albumin-to-creatinine ratio of <300 mg/g, comprising 2,459 women and 4,159 men with a mean (± SD) age of 60 ± 12 years. The exposure was baseline estimated GFR (eGFR) (mL/min/1.73 m2), treated as a categorical variable and classified into five categories: ≥90, 75-90, 60-75, 45-60, and <45, as well as a continuous variable. The outcome was progression of albuminuria category (i.e., from normoalbuminuria to micro- or macroalbuminuria or from micro- to macroalbuminuria). Hazard ratios (HRs) for the outcome were estimated using the multivariable Cox proportional hazards model. In the analysis treating baseline eGFR as a continuous variable, the multivariable-adjusted restricted cubic spline model was used. RESULTS: During the median follow-up period of 6.3 years, 1,190 individuals reached the outcome. When those with a baseline eGFR of 75-90 mL/min/1.73 m2 were considered the reference group, HRs (95% CIs) for the outcome in those with a baseline eGFR of ≥90, 60-75, 45-60, or <45 mL/min/1.73 m2 were 1.38 (1.14-1.66), 1.34 (1.14-1.58), 1.81 (1.50-2.20), or 2.37 (1.84-3.05), respectively. Furthermore, the inverse J-shaped curve was more clearly shown by the spline model. CONCLUSIONS: This study of Japanese adults with type 2 diabetes suggests that both high and low GFRs are implicated in the pathogenesis of albuminuria progression.

Kidney outcomes and all-cause mortality in people with type 2 diabetes exhibiting non-albuminuric kidney insufficiency.

AIM/HYPOTHESIS: It remains unclear whether people with diabetes exhibiting non-albuminuric kidney insufficiency have higher risk of kidney function decline and mortality compared with those exhibiting preserved kidney function without albuminuria. Furthermore, information regarding the incidence of albuminuria in people with this unique phenotype is sparse. Here, we aimed to elucidate the risk of the kidney outcomes and all-cause mortality in people with diabetes exhibiting non-albuminuric kidney insufficiency. METHODS: In this retrospective cohort study, 8320 Japanese adults with type 2 diabetes were classified into four groups based on the presence of albuminuria and kidney insufficiency at baseline, defined as urinary albumin/creatinine ratio of equal to or above 30 mg/g and eGFR of less than 60 ml min-1 1.73 m-2, respectively. The primary composite kidney endpoint was a 50% decrease in eGFR from baseline or the initiation of kidney replacement therapy. The annual percentage change in eGFR slope and progression of albuminuria category were evaluated as the secondary and tertiary kidney endpoints, respectively. All-cause death was also set as the endpoint. RESULTS: Compared with people exhibiting non-albuminuric preserved kidney function, those with non-albuminuric kidney insufficiency had the higher risk for the primary kidney endpoint (HR 4.1; 95% CI 2.5, 6.7; p < 0.001), steep percentage change in eGFR slope (-1.96%/year vs -1.36%/year, p < 0.001), incidence of albuminuria (HR 2.1; 1.7, 2.6; p < 0.001) and all-cause mortality (HR 1.5; 1.2, 2.0; p = 0.003). In the sensitivity analyses treating the incidence of albuminuria as a competing risk, people with non-albuminuric kidney insufficiency still had higher risk for the primary kidney endpoint and all-cause mortality than those with non-albuminuric preserved kidney function (subdistribution HR 2.8; 1.4, 5.6; p = 0.004; and 1.6; 1.1, 2.2; p = 0.014, respectively). CONCLUSIONS/INTERPRETATION: People with type 2 diabetes exhibiting non-albuminuric kidney insufficiency had poorer kidney outcomes and life prognosis than those exhibiting non-albuminuric preserved kidney function.

Temporal trends in the prevalence of albuminuria and reduced eGFR in Japanese patients with type 2 diabetes.

Changes over time have been shown in renal manifestations in individuals with diabetes in the United States; however, whether the trends are shared across ethnicities is unknown. We conducted this single-center serial cross-sectional study to determine temporal changes in albuminuria and reduced kidney function in Japanese patients with type 2 diabetes. This study included adult Japanese patients with type 2 diabetes who first visited our institute between 2004 and 2013. Temporal changes during the 10 years in the frequency of albuminuria ( ≥ 30 mg/g creatinine) and reduced eGFR ( < 60 mL/min/1.73 m2) were analyzed using the univariate and multivariate logistic regression analyses and Granger causality test. 5331 Japanese patients with type 2 diabetes, 1892 women and 3439 men, with the mean age of 56 ± 13 years, were studied. There was no change in the prevalence of albuminuria in the univariate analysis; however, a significantly decreasing trend was observed after adjustment for several covariates. On the other hand, patients with reduced eGFR significantly increased over time, although the statistical significance disappeared after adjustment for the covariates, including levels of serum uric acid and hemoglobin and use of renin-angiotensin inhibitors. The Granger causality test showed that time series for use of RAS inhibitors and BMI had a causative role in time series for reduced eGFR. In conclusion, prevalence of albuminuria decreased and that of reduced eGFR remained stable after adjustment for clinical characteristics in Japanese patients with type 2 diabetes during the last decade.

Effects of uric acid on kidney function decline differ depending on baseline kidney function in type 2 diabetic patients.

BACKGROUND: Most existing data regarding effects of uric acid (UA) on diabetic kidney disease have considered patients with preserved kidney function. We examined a hypothesis that there are differences in the effects of serum UA levels on the decline in kidney function depending on baseline kidney function in diabetic patients. METHODS: In this historical cohort study, 7033 type 2 diabetic patients were analyzed and classified into two groups as follows: nonchronic kidney disease (non-CKD), with an estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2 (n = 4994), and CKD, with an eGFR <60 mL/min/1.73 m2 (n = 2039). The composite endpoint was a ≥30% decrease in eGFR from baseline or the initiation of renal replacement therapy. The hazard ratio (HR) of serum UA levels at baseline was estimated using multivariate Cox proportional hazards models. RESULTS: There was a significant interaction between UA levels and baseline eGFR with respect to the endpoint (P < 0.001). The HRs of 1 mg/dL increase in UA levels were 1.13 [95% confidence interval (CI) 1.05-1.22, P = 0.002] and 0.93 (95% CI 0.88-0.99, P = 0.02) in the non-CKD and CKD groups, respectively. When patients were classified by quintile of UA levels, the HRs of those in the 5th quintile (versus 1st quintile) were 1.64 (95% CI 1.23-2.18, P < 0.001) and 0.76 (95% CI 0.58-0.99, P = 0.05) in the non-CKD and CKD groups, respectively. CONCLUSIONS: The effects of UA on kidney function decline might differ depending on baseline kidney function in type 2 diabetic patients. High UA levels are the prognostic factor only in patients with preserved kidney function.

Supplemental arginine above the requirement during suckling causes obesity and insulin resistance in rats.

Nutrition in early life is important in determining susceptibility to adult obesity, and arginine may promote growth acceleration in infants. We hypothesized that maternal arginine supplementation may promote growth in their pups and contribute to obesity and alteration of the metabolic system in later life. Dams and pups of Wistar rats were given a normal diet (15% protein) as a control (CN) or a normal diet with 2% arginine (ARG). Altered profiles of free amino acids in breast milk were observed in that the concentrations of threonine and glycine were lower in the ARG dams compared with the CN dams. The offspring of the CN and ARG dams were further subdivided into normal-diet (CN-CN and ARG-CN) groups and a high fat-diet groups (CN-HF and ARG-HF). In response to the high fat-diet feeding, the visceral fat deposits were significantly increased in the ARG-HF group (although not compared with the CN-HF group); no difference was observed between the CN-CN and ARG-CN groups. The blood glucose and insulin levels after glucose loading were significantly higher in the ARG-HF group compared with the CN-HF group. The results suggest that the offspring of dams supplemented with arginine during lactation acquired increased susceptibility to a high-fat diet, resulting in visceral obesity and insulin resistance. The lower supply of threonine and glycine to pups may be one of the contributing causes to the programming of lifelong obesity risk in offspring. Our findings also indicated that maternal arginine supplementation during suckling causes obesity and insulin resistance in rats.

Molecular and catalytic properties of monoacetylphloroglucinol acetyltransferase from Pseudomonas sp. YGJ3.

Monoacetylphloroglucinol (MAPG) acetyltransferase, catalyzing the conversion of MAPG to 2,4-diacetylphloroglucinol (DAPG), was purified from Pseudomonas sp. YGJ3 grown without Cl(-). Cl(-) and pyoluteorin repressed expression of the enzyme. SDS-polyacrylamide gel electrophoresis showed that the purified enzyme (M(r)=330 kDa) was composed of three subunits of 17, 38, and 43 kDa, and protein sequencing identified these as PhlB, PhlA, and PhlC respectively. The enzyme catalyzed the reversible disproportionation of 2 moles of MAPG to phloroglucinol (PG) and DAPG. The equilibrium constant K (=[DAPG][PG]/[MAPG](2)) was estimated to be about 1.0 at 25 °C. A KpnI 20-kb DNA fragment was cloned from the genomic DNA of strain YGJ3, and a 12,598-bp long DNA region containing the phl gene cluster phlACBDEFGHI was sequenced. PCR cloning and expression of the phl genes in Escherichia coli confirmed that expression of phlACB genes produced MAPG ATase.

Analysis of Bordetella pertussis agglutinin titers during an outbreak of pertussis at a university in Japan.

In 2007, a large outbreak of pertussis occurred at a university in Japan. Initially, a student, suffering from nocturnal cough and post-tussive vomiting for 3 weeks was diagnosed with pertussis. During the subsequent outbreak, 361 university students and staff members presented with a primary complaint of a cough. In the present study, we analyzed bacterial agglutinin titers against two Bordetella pertussis strains, Yamaguchi (epidemic strain) and Tohama (vaccine strain), in 310 patients with a cough and evaluated its diagnostic accuracy for adolescent and adult pertussis. These serological analyses showed a significant difference (P<0.001) in the levels of Yamaguchi agglutinin titer, but not in those of Tohama agglutinin titer, between patient and healthy adult groups. Therefore, the bacterial agglutination assay against strain Yamaguchi may be a useful tool for diagnosis of adolescent and adult pertussis, especially in young adults, when an agglutinin titer cutoff value of >or=160x is used in combination with clinical symptoms and other clinical laboratory tests.