Studies on sperm storage in the vas deferens of the spinifex hopping mouse (Notomys alexis)

The cauda epididymidis, with its relatively cool temperature (32-35 degrees C), is considered to be the main site of sperm storage in male mammals. However, in the adult male spinifex hopping mouse, Notomys alexis, similar numbers of spermatozoa are found in the vas deferens to those in the cauda epididymidis. The present study shows that, unlike in the laboratory mouse in which spermatozoa of the vas deferens are found mainly in the epididymal region of the duct, spermatozoa in the hopping mouse are localized mainly to the middle and urethral regions of the vas deferens which lies in the inguinal and lower abdominal region of the body cavity. After ligation of the vas deferens close to its connection with the epididymis, many spermatozoa in the vas deferens retain the potential for motility for up to 2 weeks, indicating that the viability of spermatozoa is not compromised by being restricted to core body temperature. This urethral region of the vas deferens, in which spermatozoa reside, has a highly divergent structural organization compared with that of common laboratory rodents in which there is an expanded lumen with a network of epithelial folds. Ultrastructural observations of the cells lining the duct indicate that there are not any marked differences in morphology compared with the cells lining the duct in common laboratory murids, but the infoldings of the vas deferens of the hopping mouse are highly vascular which might facilitate supply of oxygen and nutrients to the spermatozoa residing in the lumen.     

Induction of phytochemical glyceollins accumulation in soybean following treatment with biotic elicitor (Aspergillus oryzae)

The different isoflavonoid phytoalexins produced by soybeans are known to possess antioxidant and estrogenic effects, with potential health benefits in humans. Enhanced production of phytoalexins by soybean plant will help in research efforts. In this study, the effects of stress induced by Aspergillus oryzae Lu brewing 3042 on the composition of wounded surface of Nigerian soybean seeds were analyzed. Glyceollin, one of the inducible phytoalexins produced by plants, were induced in the Nigerian soybeans variety through fungal infection. Glyceollins I, II, and III were separated by preparative high performance liquid chromatography (Prep-HPLC) from other phytochemicals and had purity of 97.5%. Results from the time course study indicated that the maximum concentration of glyceollins, 0.74 mg/g, occurred at day 3 in the soybean cotyledons inoculated with A. oryzae Lu brewing 3042. The soybean seeds soak time in water was examined and a suitable soak time of 4 h was found best in the accumulation of glyceollins after the soak time study was conducted. Cut or wounded surface of soybean cotyledons produced glyceollins upon fungal treatment as elicitor and the glyceollins were confirmed by the ultra performance liquid chromatography–mass spectrometry (UPLC–MS). Analysis of elicitor-treated Nigerian soybean extract showed that A. oryzae Lu brewing 3042 treatments achieved maximum concentration of phytoalexin glyceollins at 1.32 mg/g extract dry weight. These results indicate that using food-grade A. oryzae Lu brewing 3042 elicits the biosynthesis of phytoalexins, alters the secondary metabolite profiles of the soybeans and offers enhanced bioactivity of soybean as a functional food ingredient.     

中老年奶粉中双酚A和己烯雌酚的反相高效液相色谱测定

采用反相高效液相色谱法测定奶粉中的双酚A和己烯雌酚。乙腈做提取剂和蛋白沉淀剂,乙腈-水(体积比为70∶30)为流动相,230nm波长检测。在0.005～25.00mg/L范围内,双酚A和己烯雌酚的线性相关系数分别为:0.9998和0.9999,检出限分别为:0.005、0.025mg/L,相对标准偏差在1.55%～3.46%之间,平均回收率均在85.0%以上。     

Exposure of juvenile roach (Rutilus rutilus) to treated sewage effluent induces dose-dependent and persistent disruption in gonadal duct development

Wild roach (Rutilus rutilus) have been found with intersex gonads in rivers throughout the United Kingdom. The incidence of intersexuality is strongly correlated with discharges of estrogenic treated sewage effluent into those rivers, and this has led to the hypothesis that estrogenic chemicals in effluents are feminizing wild male fish. In this study, early-life stage roach (50 days post hatch, dph) were exposed for 150 days to a graded concentration (0%, 12.5%, 25%, 50%, and 100%) of treated sewage (primarily domestic) effluent to examine the effects of exposure on sexual differentiation and development. Measurement of steroid estrogens and alkylphenolic chemicals in the effluent and a resulting dose-dependent induction of vitellogenin (VTG; a female-specific, estrogen-dependent plasma protein) confirmed that the fish had been exposed and responded to "estrogen" in the effluent. Exposure to treated sewage effluent induced feminization of the reproductive ducts in "male" roach in a dose-dependent manner (in full-strength effluent, 100% of the fish had feminized ducts), indicating that the disruption of the gonad ducts seen in wild roach is the result of exposure to treated sewage effluents during early-life stages. There were no effects of treated sewage effluent exposure on germ cell development; therefore, no oocytes occurred in the testes of the feminized male roach. Subsequent, depuration of the effluent exposed fish in "clean" water for 150 days resulted in a reduction in plasma VTG but no alteration of the feminized ducts, indicating that the effect of the treated sewage effluent on reproductive duct development was permanent. The causality of oocytes in the testes of wild male roach therefore remains to be elucidated.     

Hydrolysis of the toxic constituents (vicine and convicine) in fababean (Vicia faba L.) food preparations following treatment with β-glucosidase

Several experiments were carried out to determine whether the concentrations of vicine and convicine in fababean food preparations were reduced following heat and β-glucosidase treatment. Heating fababeans to relatively high temperatures was not effective in reducing the concentration of these glycosides. Treatment of cooked fababeans (fababean paste) with ground raw almond powder, which is a rich source of β-glucosidase (EC 3.2.1.21) activity, resulted in the hydrolysis of vicine and convicine. The degree of hydrolysis ranged from partial to complete and was dependent on the duration of the treatment period (1 to 24 h), the temperature at which treatment was carried out (1 to 30°C), the pH (6.4 to 4.6) as adjusted by the addition of lemon juice and the amount of ground almonds added to the fababean paste. For example, 88 to 89% of the glycosides were hydrolysed when 1 g of fababean paste was mixed with 0.1 g of almond powder and 0.1 ml of lemon juice and incubated at 30°C for 3 h. This study demonstrated that the concentration of vicine and convicine and their corresponding aglycones can be greatly reduced in fababean food preparations by enzymic hydrolysis.     

Dose-response effects of equine chorionic gonadotrophin (eCG) and human chorionic gonadotrophin (hCG) on early embryonic development and viable pregnancy rate in rats

The present study examined the dose-response effects of eCG treatment alone and in combination with various doses of hCG on early embryonic development in vivo and viable pregnancy rate in rats. Mated female Wistar rats were treated with eCG alone (0, 10, 20 or 40 iu), or with 20 iu eCG in combination with various doses of hCG (10, 20, 40 or 80 iu) administered 48 h later. The animals were killed on days 2, 3, 4, 5 or 14 of pregnancy and the numbers of embryos and fetuses recovered were scored. All rats treated with 0 or 10 iu eCG were pregnant. The pregnancy rate was reduced from 62.5% on day 2 to 25% on day 14 and from 31% on day 2 to 10% on day 14 in the groups treated with 20 and 40 iu eCG, respectively. The reduction in pregnancy rate induced by 20 iu eCG was negated by the increasing doses of hCG used. A 100% pregnancy rate was noted on days 2 and 3 in the groups treated with doses of hCG between 10 and 80 iu and from day 2 to day 4 in the groups treated with doses of hCG between 20 and 80 iu. However, a higher viable pregnancy rate was observed only in the group treated with 10 iu hCG compared with the group treated with 20 iu eCG and 0 iu hCG. These results imply that hyperstimulation of rats with high doses of eCG compromises pregnancy rate and markedly reduces litter size and that the addition of hCG is required for complete ovulation, which results in higher embryo yield and a delay in early embryo demise.     

Comparison of the distribution and toxicity of alpha-, beta-, and gamma-hexachlorocyclohexane (HCH) following 30 days of administration to rats

Administration of 1000 ppm alpha-HCH, 600 ppm beta-HCH and greater than or equal to 125 ppm gamma-HCH to rats caused a growth retardation. alpha-HCH and beta-HCH led to livermass enlargement. beta-HCH caused a decrease of absolute brain-mass. In case of alpha-HCH and gamma-HCH fat tissue, kidneys and adrenals had a high burden in residues. Fat tissue and adrenals had high residues of beta-HCH. The level of HCH-residues during the test period was gamma much less than beta less than alpha. The results are discussed taking into account the contradictory knowledge from literature.     

Inhibitory effect of sowthistle (Ixeris dentata) on development and expression of behavioral locomotor sensitization to nicotine in rats

The aim of this study was to investigate the effects of sowthistle (Ixeris dentata, IXD) on development and expression of nicotine-induced locomotor sensitization and underlying neuronal activation reflected by c-Fos expression in rats. Rats were pretreated with IXD 30 min before a daily injection of nicotine during an 8-day development phase and then challenged with nicotine after a 6-day withdrawal period. In another set of experiments, same IXD doses were administered once 30 min before nicotine challenge. Daily IXD treatment during development phase was not effective in blocking nicotine-induced locomotor sensitization in rats. However, a single IXD treatment after the development and withdrawal periods of nicotine sensitization significantly alleviated sensitized locomotor behavior on day 15. These behavioral results were coincident with significant inhibition of nicotineinduced c-Fos expression in the nucleus accumbens. These results indicated that IXD pretreatment significantly blocked the expression, but not the development of nicotine-induced locomotor sensitization in rats.     

Effect of enzymatic treatment on tannins and phytate in sorghum (Sorghum bicolor) and its nutritional study in rats

Sorghum is a cereal used as a food source by humans and animals. However, it presents antinutritional factors such as tannins and phytic acid, compounds that form complexes with proteins and minerals, respectively, decreasing sorghum’s digestive value. The purpose of this study was to apply tannase and phytase to sorghum and evaluate the effect on tannins and phytate level and the effect of the enzymatic treatment on Wistar rats. Tannin sorghum was treated with tannase and phytase, the effect of this treatment was measured in a study with rats, a group received a diet with raw sorghum and the other one a diet with treated sorghum. The enzymatic treatment was effective in reducing tannins and promoting the increase of inorganic phosphorus. The biological assay showed that the enzymatically treated sorghum was better than raw sorghum in the apparent digestibility of phosphorus, in the level of glucose, cholesterol and triacylglycerol. Treatment of the sorghum also resulted in lower activity of the enzymes aspartate aminotransferase and alanine aminotransferase in rat serum. The enzymatic treatment of sorghum could improve the nutritional value of this cereal while also decreasing environmental pollution.     

Quality changes in chilled Norway lobster (Nephrops norvegicus) tail meat and the effects of delayed icing

The quality deterioration of Norway lobster (Nephrops norvegicus) tail meat was monitored during ice storage. The K‐value started at 0.7% and reached a value of 39.7% on day 14. Muscle pH followed a sigmoidal pattern that reached a plateau on day 6. Bacterial load and trimethylamine (TMA) increased only after a lag phase to reach considerable levels by day 14 (5.3 log cfu and 10.2 mg (100 g)^?1, respectively). These analytical data were compared with sensory data. Principal component analysis (PCA) indicated that laboratory measures were correlated positively with the smell strength of cooked product (increasingly strong) and negatively with the smell character of raw and cooked product (sour‐ammoniacal in raw and neutral in cooked products), flavour and aftertaste (both increasingly bland–bitter). The effects of icing delays on the quality of tail meat were also evaluated. Changes in K‐values, microbial load, muscle pH and TMA indicated that the delay to icing should be no more than 4 h (at 16 °C) to ensure that quality is not compromised during subsequent post‐harvest storage.     

Effects of Cheonnyuncho (Opuntia humifusa) seeds treatment on the mass, quality, and the turnover of bone in ovariectomized rats

Cheonnyuncho (Opuntia humifusa), rich in polyphenols and flavonoids, is known to have medicinal benefits in the treatment of arteriosclerosis and inflammation. This study was undertaken to evaluate the effects of cheonnyuncho seed powder (OHS) on postmenopausal osteoporosis in ovariectomized rats. OHS treatment prevented an ovariectomy (OVX)-induced decrease in biomechanical quality of femurs. OHS also dose-dependently inhibited bone mineral density (BMD) decreases in femurs, which were accompanied by a significant decrease in skeletal remodeling, as evidenced by decreased levels of the bone turnover markers osteocalcin, alkaline phosphatase (ALP) activity, and serum and urinary Ca excretion. Micro-CT analysis of femoral metaphysics showed that OHS prevented the OVX-induced decrease in bone volume/tissue volume, trabecular thickness, and trabecular number. Concluded, the treatment with OHS improves bone biomechanical quality through modification of BMD and trabecular microarchitecture without hyperplastic effects on the uterus. For these reasons, OHS may be suitable as an alternative treatment of postmenopausal osteoporosis.     

Studies on changes in flour tocopherols following ageing and treatment of the flour with chlorine dioxide

The tocopherols in freshly milled flour were measured using two-dimensional chromatography. Total tocopherols were in the range 1500–1600 μg/100 ml, but only 17–18% of this was α-tocopherol. Aerobic storage for 190 days caused a reduction of all tocopherols by 62–67%. Treatment of the flour with chlorine dioxide at the usual commercial level caused a comparable reduction, averaging 58%; ?-tocopherol was rather less affected than α-tocopherol. Studies in human volunteers indicated that a daily supplement greater than 10 mg of tocopherol was needed to bring about a significant change in the level of α-tocopherol in the blood. When bread made from untreated and chlorine dioxide-treated flour was fed to groups of volunteers in a double-blind crossover trial for 50 days on each type of bread, no significant correlation could be found between blood tocopherol levels and the type of bread consumed. To examine whether a longer period of time on the diet was necessary, the blood tocopherol levels of thirteen English students who had habitually consumed bread made from treated flour were compared with those of thirteen French students, matched for age, who had for several years consumed French bread which is made from untreated flour. The analyses were carried out in Birmingham and in Paris by the same investigator. No significant differences in tocopherol levels were found. It is concluded that the consumption of bread made from flour treated with chlorine dioxide will have no significant effect upon the blood level of α-tocopherols under the dietary conditions at present prevailing in Britain.     

Identification of metabolites of dieldrin (HEOD) in the faeces and urine of rats

Two metabolites of HEOD have been isolated by chromatographic techniques, one from the faeces and one from the urine of rats fed for six months on a diet containing HEOD. The molccular formulae of the urinary and faecal metabolites are respectively C₁₂ H₇ O₂ Cl₅ and C₁₂ H₈ O₂ Cl₆. Structural formulae for the two compounds are suggested.     

The development of a 'clean sheep policy' in compliance with the new Hygiene Regulation (EC) 853/2004 (Hygiene 2)

The aim of this research was to identify the risk factors associated with the transfer of bacterial contamination from the fleece to the ovine carcass thereby providing the scientific basis for the development and validation of a clean sheep policy. Two hundred sheep in lairage were graded into five categories each consisting of 40 sheep. The categories were as follows; (A) clean and dry; (B) clean and wet; (C) dirty and dry; (D) dirty and wet and (E) visible dags (dung-clotted tufts of wool) categorized by the chief veterinary inspector at the slaughter plant based on the visual inspection of the hygienic status of the fleece. Microbiological evaluations of the carcasses were conducted using swab sampling methods. Total viable counts (TVCs), Enterobacteriaceae and coliform counts were obtained from 40 animals per category at four separate sites (brisket, shoulder, flank and rump) immediately after pelt removal. Statistical analysis of TVC data obtained from the carcass indicated that the dirt level of the fleece had a significant effect on contamination levels when the fleece was dry. Enterobacteriaceae and coliform counts suggest that dirt was a contributing risk factor regardless of wetness or dryness of the animal. The clean sheep policy should therefore differentiate between clean and dirty sheep and mandate additional hygiene measures for the latter.     

Effect of oestradiol treatment on mast cell populations and microflora in the vaginal cul-de-sac of seasonally anoestrous brushtail possums (Trichosurus vulpecula)

Mast cell populations in the vaginal cul-de-sac of female brushtail possums do not appear to be related to microbial invasion but changes in their density occur at oestrus, indicating a hormonal influence. The present study examined the effect of treatment with oestradiol on microflora and on mast cell numbers and their spatial location in cul-de-sac tissue of seasonally anoestrous brushtail possums. Tissue was collected from seasonally anoestrous brushtail possums (n = 6 per group) that were either untreated (anoestrous group) or were subjected to 6 days of treatment with oestradiol (oestradiol group) administered via subcutaneous implants or with the oil vehicle alone (control group). Tissue was collected aseptically for microbiological procedures and the fractionator and optical disector were used to quantify mast cell populations. Microflora populations were low (< 4.0 x 10(4) organisms g(-1)) and numbers of mast cells were similar in all groups. Mast cell density was greatest in epithelial and connective tissues from seasonally anoestrous and control animals and lowest in oestradiol-treated possums, in which there was a significant increase in cul-de-sac mass and volume. There is an inverse relationship between circulating oestrogen concentrations and mast cell density in possum cul-de-sac tissue, which is probably the result of an increase in tissue volume.     

中国人造板机械制造行业形成与发展的历史回顾（四）——用科学发展观回顾中国人造板机械制造行业起步与形成的历史

从科学发展观的角度,系统、客观地回顾了中国人造板工业及人造板机械制造行业形成、发展及演变的历史过程,介绍了在人造板机械制造行业形成过程中所发生的有影响力的大事,描述了中国人造板机械制造行业的概况