梅花鹿慢性氟中毒的骨病理学研究

对来自因１年前饲喂含氟量过高的饲料而导致鹿群慢性氟中毒鹿场的２头梅花鹿作了病理学研究。其主要病理学特征为全身骨骼多发性骨外膜性骨瘤形成，无氟斑牙变化。血钙０．１２５～０．６２４ｍｍｏｌ／Ｌ，骨组织氟含量４９９×１０－６～１０６９×１０－６。病理组织学特征为骨外膜增生亢进，骨密质外层骨小梁异常增生，并在骨密质内有变性骨单位形成，而破骨过程微弱。研究结果认为，骨瘤的形成及发展是氟的持续作用所致的进行性病变。超微结构显示，甲状旁腺呈现机能衰退状态，甲状腺滤泡旁细胞则显示机能亢进形态     

The investigation of probiotic potential of lactic acid bacteria isolated from traditional Mongolian dairy products

The aims of this study were to investigate the diversity of lactic acid bacteria (LAB) isolated from traditional Mongolian dairy products, and to estimate the probiotic potential of the isolated strains. We collected 66 samples of the traditional Mongolian dairy products tarag (n = 45), airag (n = 7), aaruul (n = 8), byasulag (n = 1) and eezgii (n = 5), from which 543 LAB strains were isolated and identified based on 16S ribosomal DNA sequence. The predominant species of those products were Lactobacillus (L.) delbrueckii ssp. bulgaricus, L. helveticus, L. fermentum, L. delbrueckii ssp. lactis and Lactococcus lactis ssp. lactis. However, we could not detect any LAB strains from eezgii. All LAB isolates were screened for tolerance to low pH and to bile acid, gas production from glucose, and adherence to Caco‐2 cells. In vitro, we found 10 strains possess probiotic properties, and almost identified them as L. plantarum or L. paracasei subspecies, based on 16S ribosomal DNA and carbohydrate fermentation pattern. These strains were differentiated from each other individually by randomly amplified polymorphic DNA analysis. Additionally, it was notable that 6/10 strains were isolated from camel milk tarag from the Dornogovi province.     

Fertilization Ability of Porcine Oocytes Reconstructed from Ooplasmic Fragments Produced and Characterized after Serial Centrifugations

Mitochondria are reported to be critical in in vitro maturation of oocytes and subsequent embryo development after fertilization, but their contribution for fertilization has not been investigated in detail. In the present study, we investigate the contribution of mitochondria to fertilization using reconstructed porcine oocytes by fusion of ooplasmic fragments produced by serial centrifugations (centri-fusion). Firstly, we evaluated the characteristics of ooplasmic fragments. Three types of fragments were obtained by centrifugation of porcine oocytes matured in vitro for 46 h: brownish (B), transparent (T) and large (L) fragments containing both B and T parts in a fragment. The production efficiencies of these types of fragments were 71.7, 91.0 and 17.8 fragments/100 oocytes, respectively. In experiments, L fragments were excluded because they contained both brownish and transparent components that were apparently intermediate between B and T fragments. Observations by confocal microscopy after staining with MitoTracker Red CMXRos^® and transmission electron microscopy revealed highly condensed active mitochondria in B fragments in contrast to T fragments that contained only sparse organelles. We reconstructed oocytes by fusion of a karyoplast and two cytoplasts from B and T fragments (B and T oocytes, respectively). The B oocytes showed higher sperm penetration (95.8%) and male pronuclear formation rates (94.2%) by in vitro fertilization than T oocytes (66.7% and 50.0%, respectively). These results suggest that the active mitochondria in oocytes may be related to their ability for fertilization.     

Socioeconomic factors influencing global paper and paperboard demand

To clarify the socioeconomic factors influencing global paper and paperboard demand, a panel data analysis was conducted covering the period 1961–2014. This study used paper and paperboard demand as the dependent variable, and a country’s economic level, Internet usage rate, plastic packaging demand, and time trend as the explanatory variables. An inverse U-shaped quadratic relationship, such as an environmental Kuznets curve, was found between economic level and paper and paperboard demand, which saturates and begins to decline as economic level increases. The economic level representing the turning point differs significantly with the use, ranging from around 37,000 US$/person for newsprint paper to around 66,000 US$/person for printing and writing paper. For both newsprint paper and printing and writing paper, demand declines owing to the spread of the Internet as the economic level rises, although this reductive effect is greater for printing and writing paper than for newsprint paper. A substitution relationship is not found between wrapping paper and corrugated cardboard on the one hand and plastic packaging on the other hand as the economic level becomes higher.     

转型中的亚洲林业(续一)

在过去的20年里,亚洲林业经历了引人注目的转型,包括从计划经济到市场经济的转变,从天然林供给木材到人工林供给木材的转变,木材替代品与非木质林产品的增加,地方分权与当地群众的参与,生态时代的发展与生态系统管理。在促进亚洲可持续森林资源管理中,市场工具、社区参与和环境服务都得到了应用。亚洲林业的转型表现出多样化,其森林、社会与环境之间的联系是丰富多彩的。     

Congenital syringohydromyelia in a crossbred (Holstein-Friesian × Japanese Black) beef calf

A 5-day-old male crossbred beef calf presented with a well-coordinated bilateral hopping gait of the hind limbs. Postmortem CT showed a poorly defined oval-shaped region at the L3–L4 spinal segments, which had high signal intensity on T2 weighted postmortem MRI images. On pathological examination, we identified a large cystic cavity filled with a large amount of cerebrospinal fluid on the cut surface of the spinal region. Histopathological examination revealed that the spinal cord parenchyma was compressed by the cystic structure, and the cystic cavity was lined with a thin layer of discrete ependymal cells, indicating syringohydromyelia. This is the first reported case of a Holstein-Friesian × Japanese Black crossbred calf with solitary syringohydromyelia. Our findings suggest that myelodysplasia with cystic cavities can be suspected by CT, without the need for MRI.     

Removal of sperm tail using trypsin and pre-activation of oocyte facilitates intracytoplasmic sperm injection in mice and rats

We examined various methods to enhance the accessibility of intracytoplasmic sperm injection (ICSI) technology to more users by making the technique easier, more efficient, and practical. First, the methods for artificially removing the mouse sperm tail were evaluated. Trypsin treatment was found to efficiently remove the sperm tails. The resultant sperm cells had a lower oocyte activation capacity; however, the use of activated oocytes resulted in the same fecundity as that of fresh, untreated sperm. Pre-activated oocytes were more resistant to physical damage, showed higher survival rates, and required less time per injection. Testing this method in rats yielded similar results, although the oocyte activation method was different. Remarkably, this method resulted in higher birth rates of rat progeny than with conventional methods of rat ICSI. Our method thereby streamlines mouse and rat ICSI, making it more accessible to laboratories across many disciplines.