Axle-less F1-ATPase rotates in the correct direction

F1-adenosine triphosphatase (ATPase) is an ATP-driven rotary molecular motor in which the central gamma subunit rotates inside a cylinder made of three alpha and three beta subunits alternately arranged. The rotor shaft, an antiparallel alpha-helical coiled coil of the amino and carboxyl termini of the gamma subunit, deeply penetrates the central cavity of the stator cylinder. We truncated the shaft step by step until the remaining rotor head would be outside the cavity and simply sat on the concave entrance of the stator orifice. All truncation mutants rotated in the correct direction, implying torque generation, although the average rotary speeds were low and short mutants exhibited moments of irregular motion. Neither a fixed pivot nor a rigid axle was needed for rotation of F1-ATPase.     

深色有隔内生真菌(DSE)引进菌株对铁皮石斛的接种效应

[目的]深色有隔内生真菌(DSE)是一类与植物共生的内生真菌,研究DSE对铁皮石斛苗生长的影响,可为铁皮石斛专用菌肥的开发利用提供理论依据.[方法]试验分为7个DSE菌株分别与铁皮石斛组培苗和盆栽苗共生培养两个阶段,按不同DSE菌株接种铁皮石斛组培苗设7个处理,另以不接种菌株为对照处理,测定不同处理下铁皮石斛组培苗生长指标;按不同DSE菌株制成的菌液浇灌盆栽苗设7个处理,以未浇菌液为对照处理,测定不同处理下铁皮石斛盆栽苗生长指标.[结果]供试菌株均能与铁皮石斛苗共生,其中菌株24L-4处理的促生作用较为突出;接种该菌株后,铁皮石斛组培苗的株高、叶宽、茎径和干重分别较对照处理显著增长33.3%、65.7%、27.3%和45.1%;铁皮石斛盆栽苗的茎径、鲜重和干重分别较对照显著增长104.0%、83.9%和114.7%;显微镜观察发现该菌株的深色有隔菌丝和类似微菌核的定殖结构分布于铁皮石斛根部皮层的细胞内.[结论]DSE真菌能明显提高铁皮石斛的生产能力,具有较好的开发利用潜力.     

Molecular detection of Anaplasma phagocytophilum in cattle and Ixodes persulcatus ticks

The tick-borne pathogen, Anaplasma phagocytophilum (A. phagocytophilum), the causative agent of human granulocytic anaplasmosis (HGA), is increasingly becoming a public health concern as an aetiological agent for emerging infectious disease. We found A. phagocytophilum infection in a pooled sample of field-collected Ixodes persulcatus (I. persulcatus) ticks from one district in Hokkaido, Japan. Thus, to further investigate the prevalence in field-collected ticks, we used PCR assays targeting the A. phagocytophilum gene encoding 44 kDa major outer membrane protein (p44) for screening of I. persulcatus ticks and samples from cattle from pastures. Out of the 281 I. persulcatus ticks, 20 (7.1%) were found to harbor A. phagocytophilum DNA. The infection rate for A. phagocytophilum in cattle was 3.4% (42/1251). In future studies, it will be necessary to investigate effects of the infection in order to understand its pathogenesis of A. phagocytophilum in domestic animals.     

Meteorological factors affecting seroconversion of Akabane disease in sentinel calves in the subtropical Okinawa Islands of Japan

Tropical Animal Health and Production - Akabane virus, the pathogen-causing Akabane disease, is an arthropod-borne virus (arbovirus) transmitted by the Culicoides biting midge. A nationwide...     

Histopathological changes in the pancreas due to decreased pancreatic blood flow in a canine tachycardia-induced cardiomyopathy model

In dogs, pancreatic acinar cell injury is thought to be caused by decreased pancreatic blood flow due to heart failure. In previous our report, it demonstrated that decreased heart function causes a significant decrease in pancreatic blood flow in heart failure dog model caused by rapid ventricular pacing (RVP). However, the types of histopathological changes remain unclear. We aimed to verify the types of histopathological changes occurring in the pancreatic tissue due to decreased heart function. After RVP for 4 weeks, atrophy of pancreatic acinar cells, characterized by a decrease in zymogen granules, was observed in all areas of the pancreas. In conclusion, the result of this study suggests that attention should be paid to ischemia/hypoperfusion injury in the pancreas.     

Molecular cloning, sequencing and phylogenetic analysis of inflammatory cytokines of swamp type buffalo contrasting with other bubaline breeds

The current research concerned in the cloning, sequencing and phylogenetic analysis of inflammatory cytokine (IL-1alpha, IL-1beta, IL-6 and TNF-alpha) genes from swamp buffalo and two bubaline breeds, CB (cross between swamp and riverine type buffalo) and the Bulgarian Murrah buffalo. Multiple sequence comparison showed a high homology between the bubaline breeds, which ranged from 99.3% to 100.0% similarity, whereas from 98.6% to 99.0% compared to cattle. The phylogenetic analysis had confirmed and justified the degree of relationship between these bubaline species and their distinctness to each other by the bootstrap value (%) generated. These findings were discussed with particular attention to the diversity of the inflammatory cytokine proteins within closely related species. The result of this study concluded that a small difference in the cytokine structures might be the reason behind or has a contributory factor on the previous reports about the existence of disease resistance. However, in-depth study is necessary to further qualify these findings.     

Distinguishable staining with neutral red for GFP-marked and GFP-nonmarked <Emphasis Type="Italic">Fusarium oxysporum</Emphasis> strains simultaneously colonizing root surfaces

 Green fluorescent protein (GFP)-marked Fusarium oxysporum f. sp. melonis and nonmarked F. oxysporum f. sp. fragariae were stained with neutral red. The neutral red stained vacuoles of the fungi without disturbing GFP fluorescence in the cytoplasm. GFP-marked fungi showed fluorescent hyphae with dark-stained vacuoles, whereas nonmarked fungi were detected as nonfluorescent hyphae with dark-dotted vacuoles. Root colonization by these two fungi was monitored using this method. Microconidia attached similarly to the root surface and elongated vegetative hyphae. Only the pathogenic fungi invaded, causing necrosis at the inoculation site. Thus, the present method enabled us to track simultaneously the various formae speciales of F. oxysporum colonizing the root surface. Received: March 25, 2002 / Accepted: September 27, 2002     

Authentication of flying-fish-meal content of processed food using PCR-RFLP

Nucleotide sequence and polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis of the 3′-portion of the mitochondrial 16S RNA gene (rDNA) coding sequence were used to differentiate between flying fishes and other fishes that are frequently used in ago-noyaki production. In this study, we successfully distinguished between flying fishes and the other fishes by combining amplified DNA fragments with universally designed primers and digesting the PCR products with AfaI and MfeI restriction endonucleases. PCR-RFLP of 15 ago-noyaki, 2 noyaki, and 8 other processed flying-fish products were analyzed to authenticate flying-fish content among processed seafood products. After digestion of the PCR products with both enzymes, we found that all ago-noyaki and processed flying fish products contained either two or three DNA fragments of ~200, 300, and 530 bp, and noyaki samples (which do not contain flying fish) contained only one fragment of ~530 bp. Here, we present a new procedure to confirm the content of flying-fish meal in ago-noyaki.     

旱区坡耕地土壤层析水流动态模拟研究

水分是旱区坡耕地作物生长的关键因素。依据土壤水动力学和守恒原理,建立土壤层析水流模拟模型并开发成计算机模拟模型,采用洛阳旱区坡耕地长期定位试验数据对其进行了验证,模拟值与实测值误差绝对值控制约在10%以内,表明该模型可以应用于旱区坡耕地土壤水分的动态变化研究中。