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Background and Aim: Knowledge on the risk of gastrointestinal (GI) bleeding in hemodialysis patients is limited. We evaluated the risk of GI bleeding in hemodialysis patients compared with non‐hemodialysis patients. Methods: We performed a retrospective cohort study from 1996 to 2017 at the Graduate School of Medicine, University of Tokyo, and Horinouchi Hospital. We analyzed patients on hemodialysis for chronic renal failure and controls not on hemodialysis. The primary endpoint was GI bleeding. A survival analysis was performed to estimate the cumulative incidence and hazard ratio of GI bleeding. Results: A total of 14 451 patients were analyzed (417 hemodialysis and 14 034 non‐hemodialysis patients). In total, 524 GI bleeding events occurred. Upper and lower GI bleeding occurred in 432 and 92 patients in the hemodialysis and non‐hemodialysis groups, respectively. The most frequent source of upper and lower GI bleeding was gastric ulcer and colonic diverticular bleeding, respectively. The cumulative incidence of GI bleeding was 4.44% at 1 year, 7.15% at 3 years, and 10.40% at 5 years in hemodialysis patients; the respective rates were 2.35%, 2.98%, and 3.79% in non‐hemodialysis patients during a mean follow‐up period of 3.5 years. Hemodialysis was significantly associated with an increased risk of GI bleeding after adjustment (hazard ratio 1.67, P = 0.01, 95% confidence interval 1.13–2.50). Conclusions: Hemodialysis patients had a GI bleeding rate of 10% over 5 years, and hemodialysis was a risk factor for GI bleeding. [ABSTRACT FROM AUTHOR]

To examine the effect of storage temperature on the emission of methane (CH4) and carbon dioxide (CO2) and on recovery of nutrients from raw dairy manure slurry (RS) and slurry digested in a methane digester (DS), both slurries were stored in closed 100 L steel tanks under psychrophilic conditions (5, 10, 15 and 20°C) for a 150 day period. As the storage temperature increased, total methane emission increased in both types of slurry. The amount of methane emitted per unit of volatile solids of the RS and DS was 0.19 L/g and 0.10 L/g, respectively. The respective carbon dioxide emissions were 0.20 L/g for RS and 0.12 L/g for DS at 20°C of storage temperature. At temperatures greater than 15°C, the methane concentration in the emitted gas remained more than 40% of the total gas. During the experimental period, in excess of 90% of the total Kjeldahl nitrogen in these slurries was recovered (91.4–93.7% for RS and 93.7–98.4% for DS) after storage, and ammonium nitrogen was recovered in excess of 100% (100.1–143.2% for RS and 106.7–143.2% for DS storage tanks) because of the mineralization of organic nitrogen in the influent. These results indicate that manure slurry characteristics and storage temperature have significant impacts on methane emission. It can be concluded that on typical farms located in northern Japan, methane emission from manure storage tanks during late fall, winter and early spring may be negligible, because of manure temperatures less than 10°C. During late spring, summer and early fall, methane emissions can be substantially reduced by using underground storage to maintain lower manure temperatures. [ABSTRACT FROM AUTHOR]

Chondro-4-sulfatase and chondro-6-sulfatase from Proteus vulgaris and &Delta4hexuronate-2-suIfatase from Flavobacterium heparinum are potentially useful tools for structural studies of chondroitin sulfate and dermatan sulfate. Their substrate specificities were investigated with various structurally defined, sulfated hexasaccharides isolated from chondroitin sulfate as described in the accompanying report [Sugahara, K., Nadanaka, S., Takeda. K. &kojima, T. (1996) Eur. J.Biochem, 239, 871-880]. The results indicated that Δ4 hexuronate-2-sulfatase released an ester sulfate from C2 position of the Δ hexuronate residue located at tile non-reducing terminus, while chondro-4-sulfatase removed an ester sulfate from the C6 position of the GaINAc residue at the reducing end of the hexasaccharides, Chondro-4-su1fatase acted preferentially on an ester sulfate on the C4 position of the GaINAc residue at the reducing end under mild incubation conditions. but also released a sulfate group under harsh conditions from the C4 position of the GalNAc residue at the internal positions of the hexasaccharide chains, unless the GaINAc residue had another ester sulfate on its C6 position. The results demonstrated the usefulness of the sulfatases as tools for the structural characterization of chondroitin sulfate oligosaccharides. [ABSTRACT FROM AUTHOR]

The enzymatic action of highly purified chondroitin ABC lyase from Proteus vulgaris is dependent on the size of the substrate. and the enzyme does not cleave tetrasaccharides, irrespective of their sulfation profiles [Sugahara, K . Shigeno. K.., Masuda, M., Fujii. N.,. Kurosaka, A. & Takeda. K. (1994) Carbohydr Res. 255. 145- 1631. To characterize the enzyme action in more detail we isolated nine sulfated hexasaccharides from commercial shark cartilage chondroitin sulfate D. after partial digestion with highly purified chondroitin ABC lyase. by means of gel chromatography and HPLC on an amine-bound silica column. Structural analysis by 500-MHz iH-NMR spectroscopy. and enzymatic digestion in conjunction with HPLC. demonstrated that these hexasaccharides, with the common core saccharide structure Δ4HexA(α1-3 )Ga1NAc(β1-4)GIcA(Β1 -3 )GalNAc(β1 -4)GlcA (β1-3)GaINAc (where ΔHexA and GlcA represent 4-deoxy-α-L-threo-hex-4-enepyranosyluronic acid and glucuronic acid, respectively) near three or four sulfate groups in different combinations. In the hexasaccharides, the D disaccharide unit GIcA2- SO3- (β3 )GaINAc6SO3- which is characteristic of chondroitin sulfate D, was arranged on the reducing side of the A disaccharide unit GlcA(β1-3)GalNAc4SO3- and thus formed an A- D- tetrasaccharide sequence GlcA(β1-3)Ga1NAc4SO3- (β1-4)GIcA2SO3- (β1-3)GaINAc6SO3-. Analysis of the degradation products of these hexasaucharides with highly purified chondroitin ABC lyase indicated that the enzyme preferentially acted on the unsaturated hexasaecharides in an exolytic fashion and removed an unsaturated disaccharide unit from the non-reducing termini, irrespective of the sulfation profiles of the hexasaceharides. [ABSTRACT FROM AUTHOR]