Supplementing transglucosidase with a high-fiber diet for prevention of postprandial hyperglycemia in streptozotocin-induced diabetic dogs

Indigestible oligosaccharides have been shown to normalize blood glucose and insulin concentration thereby promoting good health and preventing diseases, such as diabetes. Transglucosidase (TG, α-glucosidase, enzyme code (EC) 3.2.1.20) is an enzyme capable of converting starch to oligosaccharides, such as iso-malto-oligosaccharides from maltose, via the action of amylase. The aim of this study was to evaluate whether oral administration of TG with maltose or dextrin is capable of reducing post-prandial serum glucose concentration in experimentally streptozotocin (STZ)-induced diabetic dogs fed on a high-fiber diet. Five healthy and five STZ-induced diabetic dogs were employed in this study. TG supplementation with dextrin or maltose had no detrimental effect in healthy dogs. In fact, TG and dextrin exhibited a flatlined serum glucose pattern, while reducing mean post-prandial serum insulin and glucose concentration as compared to control diet alone. When TG supplementation was tested in STZ-induced diabetic dogs under the context of a high fiber diet, a 13.8% and 23.9% reduction in mean glucose concentration for TG with maltose and dextrin, respectively was observed. Moreover, TG with dextrin resulted in a 13% lower mean post-prandial glucose concentration than TG with maltose, suggesting that dextrin may be a more efficient substrate than maltose when used at the same concentration (1 g/kg). Our results indicate that TG supplementation with diet can lead to lower postprandial glucose levels versus diet alone. However, the efficacy of TG supplementation may depend on the type of diet it is supplemented with. As such, TG administration may be useful for preventing the progression of diabetes mellitus and in its management in dogs.     

Electron microscopical observations of psittacine beak and feather disease in an Umbrella cockatoo (Cacatua alba).

Psittacine beak and feather disease (PBFD) was diagnosed in an umbrella cockatoo (Cacatua alba) with severe feather dystrophy and loss. Electron microscopically, the intranuclear and intracytoplasmic inclusion bodies observed by light microscopy were composed of viral particles forming paracrystalline arrays, whorls, semicircles or concentric circles. Recovered viral particles from the skin and feather follicle tracts were icosahedral and 15 to 20 nm in diameter.     

Prominent expression of spinocerebellar ataxia type-1 (SCA1) gene encoding ataxin-1 in LH-producing cells, LbetaT2

The LH-producing cell line, LbetaT2, and non LH-producing cell line, alphaT3-1 cells, established from a pituitary tumor, were employed for cDNA subtraction cloning to identify genes with expression unique to LH producing cells. Several cDNAs that code for known as well as for many unidentified clones were discovered. Most clones were the spinocerebellar ataxia type-1 (SCA1) gene encoding ataxin-1, the abnormality of which causes neurodegeneration and loss of cerebellar Purkinje cells. We examined whether the expression of SCA1 gene in LbetaT2 cells is related to hormone production. We also compared the expression of SCA1 with that in various other pituitary tumor derived cell lines, and confirmed the prominent expression of SCA1 in LbetaT2 cells. The effect of gonadal factor(s) for SCA1 gene expression was examined. The expression level in female rats was low and did not change during the estrus cycle, but increased significantly after ovariectomy and did not return to the normal level under low and high doses of estrogen. In the male pituitary SCA1 gene expression increased markedly after castration and was not decreased by estrogen or testosterone. The Ontogeny of SCA1 gene expression was investigated in porcine fetal and postnatal pituitaries and revealed biphasic and sexually dimorphic expression. Transient expression of SCA1 gene was observed at fetal day 50 and 65 in males and day 40 in females, followed by a decline and increased expression before birth in both genders. Thus the expression of SCA1 gene is prominent in LH-producing cells and is not under direct control of gonadal factor(s) in both genders. In addition to the variable expression of SCA1 gene during the fetus period, the present results provide a novel aspect to the understanding of Boucher-Neuhauser syndrome (Ataxia Hypogonadism Choroidal Dystrophy).     

Perirenal pyelocaliceal diverticulum in an infant cat

A 3-month-old female tortoise-shell cat showing azotemia died with a marked swollen abdomen. Necropsy revealed a huge perirenal cyst (8.5 x 6.0 x 4.5 cm) on the ventral aspect of the right kidney. The cyst was filled with the pellucid yellow fluid with a smell of urine. The lumen was connected with irregularly dilated renal pelvis by a narrow channel passing through the renal parenchyma. The cyst was lined by epithelial cells and its wall was consisted of collagen fibers and smooth muscle cells as that of the renal pelvis and ureter. Renal parenchyma adjacent to the channel showed interstitial infiltration of the lymphoid cells. The cyst was a diverticulum of the renal pelvis due to an impaired development.     

Prevention of biofilm formation with a coating of 2-methacryloyloxyethyl phosphorylcholine polymer

Device-associated infections are serious complications, and their prevention is an issue of considerable importance. Since biofilms are responsible for these refractory infections, effective methods to inhibit biofilm formation are required. In this investigation, stainless steel plates with and without 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer, i.e., poly (MPC-co-n-butyl methacrylate) (PMB) coating, were incubated in a medium containing bacteria. In the course of incubation, half of the specimens received antibiotics. The specimens were stained for nucleic acid and polysaccharides, and then examined with a confocal laser scanning microscope. The numbers of bacteria on the specimen surfaces were evaluated by an ATP assay. On the surfaces of the specimens without PMB coating, the formation of a biofilm enveloping bacteria was confirmed. The addition of antibiotics did not effectively decrease the number of bacteria. On the other hand, on the surfaces of the specimens with PMB coating, no biofilm formation was observed, and the number of bacteria was significantly decreased. The addition of potent antibiotics further decreased the number of bacteria by 1/100 to 1/1000 times. The PMB coating combined with the validated use of antibiotics might provide a method for the simultaneous achievement of biocompatible surfaces of devices and the prevention of device-associated infections.     

Cell wall modification during development of mealy texture in the stony-hard peach “Odoroki” treated with propylene

The melting peach cultivar “Akatsuki” [Prunus persica L. Batsh] develops melting texture during ripening, but the stony-hard peach cultivar “Odoroki”, softens and develops a mealy texture when treated with propylene. Cell wall polysaccharides were fractionated as 1,2-diaminocyclohexanetetraacetic acid (CDTA)-, Na₂CO₃-, NaOH-soluble fractions, or the cellulosic residues that remained after solvent extraction. Size-exclusion chromatography of the CDTA-soluble fraction revealed a limited depolymerization of polyuronides in mealy “Odoroki” fruit, accompanying a lower level of endo-polygalacturonase (endo-PG) and a higher level of exo-PG activities compared to melting “Akatsuki” fruit. “Akatsuki” fruit showed increases in the arabinose, galactose and rhamnose contents in the CDTA-soluble fraction. These neutral sugars decreased in the Na₂CO₃-soluble and cellulosic residue fractions during ripening. Similar changes were observed for neutral sugars other than arabinose during softening in mealy “Odoroki” fruit. Arabinose content did not increase in the CDTA-soluble fraction of “Odoroki” fruit; however, arabinose content decreased in the Na₂CO₃-soluble fraction and in the cellulosic residue as observed for “Akatsuki” fruit. A significant increase in α-l-arabinofuranosidase activity, about 10 times higher than for “Akatsuki” fruit, was observed in propylene-treated mealy “Odoroki” fruit. Differences in ripening-associated metabolic changes in the cell walls of these peach cultivars seem to be related to their differences in texture.     

Inheritance of the concentration of water-soluble carbohydrates and its relationship with the concentrations of fibre and crude protein in herbage of cocksfoot (Dactylis glomerata L.)

The concentration of water‐soluble carbohydrates (WSC) of cocksfoot is lower than that of other temperate grasses. Increasing the WSC concentration in cocksfoot is important in increasing its digestibility and preference by ruminants. The genetic variation in mono‐ and disaccharides, fructans and total WSC concentrations and their inter‐relationships with crude protein (CP) and fibre concentrations of cocksfoot (Dactylis glomerata L.) at the vegetative growth stage in half‐sib cross populations were assessed in two experiments conducted under spaced planting and sward conditions. There was a wide range in the means for concentrations of fructan, WSC and neutral‐detergent fibre (NDF) in parents and progeny whereas there was a narrow range of the means for concentrations of mono‐ and disaccharides, CP and acid‐detergent fibre (ADF). Mean concentrations of mono‐ and disaccharides showed the smallest range. Mean squares of entries in parents and progenies were significant for mono‐ and disaccharides, fructan and total WSC concentrations in all populations. The entry × year interactions for fructan and total WSC concentrations were significant in the parents and the half‐sib progeny. However, the entry × year interactions for mono‐ and disaccharide concentrations in progeny were not significant. Concentration of WSC was under genetic control as mean squares of the concentration values were significant and variance components for all traits were significantly larger than zero. There were negative genetic correlations between WSC and ADF and NDF concentrations. Narrow‐sense heritabilities (h_n) estimated from variance components of progeny for total WSC concentrations were 0·59 and 0·53 in sward and spaced planting conditions respectively. The h_n of fructan and WSC concentrations were similar in both sward and spaced planting conditions, whereas that of mono‐ and disaccharide concentrations varied from 0·20 to 0·69. It was found that the genetic variation of the total WSC concentration in cocksfoot depended mainly on genetic variation in fructan concentration. These results suggested that the forage quality of cocksfoot at the vegetative growth stage was influenced by an additive gene effect and could be improved genetically by recurrent selection.     

齐氏田中鳑鲏的早期发育研究

通过对齐氏田中鳑鲏(Tanakia chii)人工授精和培育(22℃恒温环境)阶段早期发育的观察,描述了其仔稚鱼发育形态特征。初孵仔鱼卵黄囊饱满,呈淡黄色,表皮布满微突;3日龄仔鱼卵黄囊两侧向上突起,尾部鳍褶延展变大;6日龄仔鱼眼囊发育;8日龄仔鱼眼囊有黑色素,晶状体形成;11日龄仔鱼口形成,脑开始发育,体上有黑色素出现;15日龄仔鱼鳃沟和肛门形成,背鳍和臀鳍的鳍基出现,尾鳍下叶鳍条形成;21日龄仔鱼头与躯干分界明显,鳔分化为前鳔和后鳔,背部和臀部鳍条数目分别为8和10枚,身体黑色素连接成条带状,虽然残存有卵黄囊,但已经开口并摄食。31-36日龄仔鱼胸鳍呈膜状鳍褶,腹鳍出现鳍条,尾鳍呈深叉形。61-66日龄稚鱼,鳞片出现,体中线后半部具一条黑色素带,稚鱼出现集群游动现象。仔鱼体长的生长呈阶段性:1-26日龄仔鱼生长较为平缓;26-81日龄生长较快。综合21日龄仔鱼卵黄囊残留很少并开口摄食的特征,我们推测在孵化后21日为自然条件下齐氏田中鳑鲏的出蚌时间。同时,仔鱼的感觉、摄食、呼吸和游泳器官在早期阶段快速发育。这些器官在仔鱼的早期快速发育,使出蚌后的仔鱼在最短的时间内获得与早期生存相关的各种能力,提高了出蚌后仔鱼的生存能力。     

Characterization of monoclonal antibodies against fowl adenovirus serotype 1 (FAV1) isolated from gizzard erosion

Six clones of monoclonal antibodies (Mabs) to fowl adenovirus (FAV) serotype 1 were produced. All Mabs reacted positively by enzyme-linked immunosorbent assay. Three Mabs recognized the putative 100-kD hexon protein and reacted to serotype 1 specifically by western blot analysis but did not react to other FAV serotypes (2, 3, 4, 5, 6, 7, and 8a). These Mabs will be useful for immunodiagnosis of FAV serotype 1 infection in chickens with gizzard erosion and in further research studies involving the genomes and proteins of FAV serotype 1.