Treatment of prostatic abscesses by aspiration of the purulent matter and injection of tea tree oil into the cavities in dogs

Ultrasonography-guided transabdominal needle aspiration was carried out to remove 3 to 14 ml of purulent matter from the cavities of prostatic abscesses in 6 dogs, and the same volume of tea tree oil was injected into the cavities to treat the abscesses. The same treatment was repeated 3 weeks later in 4 dogs, and subsequent disappearance of the purulent matter in the cavities and a marked reduction in the volume of the cavities were observed. These findings indicate that the treatment of prostatic abscesses by aspiration of the purulent matter and injection of tea tree oil into the cavities is very effective in dogs.     

Effects of administration of glucocorticoids and feeding status on plasma leptin concentrations in dogs

OBJECTIVE: To investigate effects of short- and long- term administration of glucocorticoids, feeding status, and serum concentrations of insulin and cortisol on plasma leptin concentrations in dogs. ANIMALS: 20 nonobese dogs. PROCEDURE: For experiment 1, plasma leptin concentrations and serum concentrations of insulin and cortisol were monitored for 24 hours in 4 dogs administered dexamethasone (0.1 mg/kg, IV) or saline (0.9% NaCl) solution for fed and nonfed conditions. For experiment 2, 11 dogs were administered prednisolone (1 mg/kg, PO, q 24 h for 56 days [7 dogs] and 2 mg/kg, PO, q 24 h for 28 days [4 dogs]) and 5 dogs served as control dogs. Plasma leptin and serum insulin concentrations were monitored weekly. RESULTS: For experiment 1, dexamethasone injection with the fed condition drastically increased plasma leptin concentrations. Furthermore, injection of saline solution with the fed condition increased plasma leptin concentrations. These increases in plasma leptin concentrations correlated with increases in serum insulin concentrations. Dexamethasone injection with the nonfed condition increased plasma leptin concentrations slightly but continuously. Injection of saline solution with the nonfed condition did not alter plasma leptin concentrations. For experiment 2, prednisolone administration at either dosage and duration did not alter plasma leptin concentrations in any dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Dexamethasone injection and feeding increased plasma leptin concentrations in dogs. In addition, dexamethasone administration enhanced the effect of feeding on increases in plasma leptin concentrations. Daily oral administration of prednisolone (1 or 2 mg/kg) did not affect plasma leptin concentrations in dogs.     

Postprandial changes in leptin concentrations of cerebrospinal fluid in dogs during development of obesity

OBJECTIVE: To evaluate postprandial changes in the leptin concentration of CSF in dogs during development of obesity. ANIMALS: 4 male Beagles. PROCEDURES: Weight gain was induced and assessments were made when the dogs were in thin, optimal, and obese body conditions (BCs). The fat area at the level of the L3 vertebra was measured via computed tomography to assess the degree of obesity. Dogs were evaluated in fed and unfed states. Dogs in the fed state received food at 9 AM. Blood and CSF samples were collected at 8 AM, 4 PM, and 10 PM. RESULTS: Baseline CSF leptin concentrations in the thin, optimal, and obese dogs were 24.3 +/- 2.7 pg/mL, 86.1 +/- 14.7 pg/mL, and 116.2 +/- 47.3 pg/mL, respectively. In the thin BC, CSF leptin concentration transiently increased at 4 PM. In the optimal BC, baseline CSF leptin concentration was maintained until 10 PM. In the obese BC, CSF leptin concentration increased from baseline value at 4 PM and 10 PM. Correlation between CSF leptin concentration and fat area was good at all time points. There was a significant negative correlation between the CSF leptin concentration-to-serum leptin concentration ratio and fat area at 4 PM; this correlation was not significant at 8 AM and 10 PM. CONCLUSIONS AND CLINICAL RELEVANCE: Decreased transport of leptin at the blood-brain barrier may be 1 mechanism of leptin resistance in dogs. However, leptin resistance at the blood-brain barrier may not be important in development of obesity in dogs.     

Spatiotemporal distribution of Flavobacterium psychrophilum and ayu Plecoglossus altivelis in rivers revealed by environmental DNA analysis

Outbreaks of bacterial cold-water disease (BCWD), caused by Flavobacterium psychrophilum, are widespread in Japan, especially among ayu Plecoglossus altivelis. There are few investigations of F. psychrophilum in river water, and its seasonal distribution has not been clarified. We aimed to identify the spatiotemporal dynamics of F. psychrophilum and ayu to provide information that is useful for establishing a countermeasure for BCWD. Quantitative analysis of environmental DNA (eDNA) was used to clarify the year-round dynamics of ayu and F. psychrophilum. We sampled river water from the Nagara and Ibi rivers in Japan, and conducted monthly water sampling and eDNA quantification. Changes in the eDNA concentration of ayu were consistent with the known life histories of the fish. There was a strong negative correlation between the eDNA concentration of F. psychrophilum and water temperature, suggesting a strong dependence of F. psychrophilum dynamics in the river on water temperature. Furthermore, relatively high eDNA concentrations were recorded for both organisms in early summer and fall, suggesting that ayu is infected with F. psychrophilum during these seasons when experiencing up- and downmigration, respectively.

     

Isolation of extracellular protein from greenhouse soil

Although extracellular proteins may play an important role in the soil environment, these proteins are difficult to isolate because they are immediately degraded by soil microbes, or become associated with clay mineral and humic substances. We developed a method of isolating extracellular proteins from greenhouse soils. Phosphate buffer (pH 6.0) was used to extract protein from soil. A phosphate buffer with higher pH was not recommended because it extracted a large amount of non-proteinaceous organic matter as well as protein and, as a result, the extracted protein was difficult to separate by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE). After removing cells by filtration, proteins dissolved in the soil extract were recovered by precipitation with 5% trichloroacetic acid (TCA) and isolated by SDS-PAGE. Proteins were detected in 10 of 32 soil samples derived from different greenhouses and the protein bands ranged in apparent molecular mass from 35 to 68 kDa, suggesting that some of soils derived from greenhouse culture contained significant amounts of a specific protein soluble in 67 mM phosphate buffer (pH 6.0). N-terminal amino acid sequence of one of the isolated proteins was found to be a homologue of thermostable cellulase produced by the genus Humicola, a thermophilic fungus.     

Triterpene glycosides of Siraitia grosvenori inhibit rat intestinal maltase and suppress the rise in blood glucose level after a single oral administration of maltose in rats

The effect of the crude extract from Siraitia grosvenori Swingle (SG-ex) on the postprandial rise in blood glucose level was investigated. The increase in plasma glucose level in response to the oral administration of maltose was significantly suppressed in rats when SG-ex was given orally 3 min before the maltose administration. There was, however, no effect when glucose was administered instead, suggesting that the antihyperglycemic effect of SG-ex is elicited by inhibition of maltase in the small intestinal epithelium. In vitro, SG-ex inhibited rat small intestinal maltase. Similar effects were also observed both in vivo and in vitro when the concentrate of the sweet elements (triterpene glycosides) prepared from SG-ex was used. Furthermore, the main sweet element of SG-ex, mogroside V, and some minor elements such as mogroside IV, siamenoside I, and mogroside III also exhibited maltase inhibitory effect with IC50 values of 14, 12, 10, and 1.6 mM, respectively. These results suggest that SG-ex exerts anti-hyperglycemic effects in rats by inhibiting maltase activity and that these effects are at least partially exerted by its sweet elements, triterpene glycosides.     

The canine RAD51 mutation leads to the attenuation of interaction with PALB2

RAD51 forms a complex with BRCA2 and plays a central role in the DNA damage response pathway that is associated with homologous recombination. The structures of RAD51 and its homologues are highly conserved from prokaryotes to higher eukaryotes. Although a large number of BRCA2 mutations have been reported, there are only a few reports on the mutations of RAD51, which have been shown in humans and dogs. However, several mutations of canine RAD51 were identified from mammary gland tumour tissues in a recent study. Some of these mutations seem to have an influence on the homo‐oligomerization or interaction with “Partner and localizer of BRCA2” (PALB2). In this study, we cloned the canine PALB2 homologue and investigated the effect on its interaction with the RAD51 mutants to evaluate the alteration in the function of RAD51 mutants. The A209S and T225S mutants of RAD51 show an attenuation of the interaction between RAD51 and PALB2. These results indicate that the canine RAD51 mutations can potentially alter the homologous recombination pathways in response to DNA damage in dogs.     

A cytotoxic ribonuclease targeting specific transfer RNA anticodons

The carboxyl-terminal domain of colicin E5 was shown to inhibit protein synthesis of Escherichia coli. Its target, as revealed through in vivo and in vitro experiments, was not ribosomes as in the case of E3, but the transfer RNAs (tRNAs) for Tyr, His, Asn, and Asp, which contain a modified base, queuine, at the wobble position of each anticodon. The E5 carboxyl-terminal domain hydrolyzed these tRNAs just on the 3' side of this nucleotide. Tight correlation was observed between the toxicity of E5 and the cleavage of intracellular tRNAs of this group, implying that these tRNAs are the primary targets of colicin E5.     

中华绒螯蟹主要呈味成分研究

用邻苯二甲醛（OPA）柱前衍生高效液相色谱法对中华绒螫蟹可食部分（肌肉、肝脏、性腺）的游离氨基酸组成及含量进行了研究分析，结果发现：中华绒螯蟹各可食部分抽提液中主要有19种氨基酸，精氨酸、丙氨酸、甘氨酸、牛磺酸、脯氨酸、赖氨酸、谷氨酸、亮氨酸、缬氨酸、酪氨酸、异亮氨酸、丝氨酸这12种氨基酸在各可食部分中的含量均超过10mg／100g，而其中又以精氨酸、丙氨酸、甘氨酸、脯氨酸和牛磺酸为主，这5种氨基酸含量占游离氨基酸总量的50％以上。此种游离氨基酸组成模式与蛛雪蟹、勘察加拟石蟹等海水蟹中的游离氨基酸分布基本相似。而中华绒螯蟹区另4于蛛雪蟹、勘察加拟石蟹等海水蟹的一个主要特征是其肌肉抽提液中的丙氨酸含量明显高于它们，是它们的3倍。相反的是中华绒螫蟹肌肉抽提液中的牛磺酸含量（80mg／100g以下）明显低于蛛雪蟹、勘察加拟石蟹中的含量（150—400mg／100g）。