Efficacy of injectable doramectin in the therapy and control of Dermatobia hominis infestations in Latin America     

R. A. Muniz  R. Cerqueira-Leite  A. Coronado  O. Soraci  O. Umehara  J. Moreno  J. Errecalde 《Veterinary parasitology》1995,60(3-4):265-271

Three studies were conducted in Latin America, one in Brazil, one in Venezuela and one in Argentina, using a common protocol to investigate the efficacy of a single subcutaneous injection of doramectin at 200 μg kg⁻¹ (1 ml per 50 kg) for the treatment and control of Dermatobia hominis infestations in cattle raised under commercial conditions. In each study, two groups of 20 animals each were allocated on the basis of D. hominis nodules present 24 h before treatment to a treated group (T1), or to a control group (T2) which received saline solution at 1 ml per 50 kg of live weight. All cattle were injected in the mid-dorsal cervical region and examined on treatment day and 2, 7, 15 and 30 days post-treatment (p.t.). At each observation day the number of D. hominis nodules was counted and the viability of the larvae inside them was assessed and recorded. Treatment with doramectin was 100% effective in eliminating D. hominis larvae and in controlling the re-establishment of the parasite under field conditions of continuous reinfestation. During the first 48 h p.t., dead larvae of different ages were found outside or partially outside the nodules in animals of the doramectin groups. After 48 h p.t., no live larvae were found inside existing nodules, nor did new nodules develop in animals of the doramectin groups in any of the three studies. When compared with nodule counts in the control group on the same observation day or with parasite burdens on the same animal before treatment, doramectin-treated animals began to eliminate parasitic nodules at 48 h p.t. Efficacy reached 100% at 7 days p.t. and remained at 100% on subsequent observation days (P<0.05). None of the doramectin-treated animals exhibited any clinical signs of adverse reaction to medication.  相似文献   

Oxazolone-induced gastrointestinal disorders enhance the oral transmission of AA amyloidosis in mice     

Hiroto KOBAYASHI  Susumu IWAIDE  Naoki UJIKE  Tomoaki MURAKAMI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(6):935

Amyloid A (AA) amyloidosis is a lethal disease characterized by systemic AA amyloid deposition, and is reported in many animal species. Despite experiments have shown that AA amyloidosis can be transmitted orally, horizontal transmission and cross-species transmission are concerns, the transmission mechanism has been unknown. In this study, we examined the oral transmission efficiency of AA amyloidosis using oxazolone-induced gastrointestinal disorder mice. As a result, the upper or lower gastrointestinal disorder groups developed more severe amyloid deposition in systemic tissues than the group without gastrointestinal disorders. The results of this study suggest that gastrointestinal damage promotes the oral transmission of AA amyloidosis.  相似文献   

Importance of starting age for myelotoxicity study in dietary restricted rats     

Asanuma F  Miyata H  Iwaki Y  Kimura M  Matsumoto K 《Journal of toxicologic pathology》2009,22(3):153-166

The aim of this study was to prove our hypothesis that adult rats with lowering of body weight gain, rats at 12 weeks of age as an example, are suitable for evaluation of myelotoxicity. Age-related differences between young rats (6-week-old study) and adult rats (12-week-old study) were analyzed in hematological examination values. The data of the young rats were reprinted from our previous report (Miyata et al., 2009) since our hypothesis was verified by comparison with that previous report. Several experimental groups were defined for the 12-week-old study as well as for the 6-week-old study; these included 5-fluorouracil (5-FU) treated groups receiving 12, 15 and 18 mg/kg/day (FU12, FU15 and FU18), pair-feeding groups (R12, R15 and R18 receiving the same amount of food as in the FU12, FU15 and FU18 groups, respectively) and a nontreated control group. Numerous hematologic and bone marrow parameters in the 5-FU treated groups were comparable to those in the corresponding pair-feeding groups in both age studies. Generally, the influences of undernutrition were more apparent in the young rats than in the adult rats. Histopathological examinations showed a decrease in hematopoiesis in the bone marrow in the 5-FU treated and pair-feeding groups. No apparent differences were observed in the decreased hematopoiesis between the 5-FU treated and pair-feeding groups in the 6-week-old study, but a difference between these groups was noted in the 12-week-old study; decreased hematopoiesis was more frequently noted in the 5-FU treated groups. These facts suggest that adult rats are more suitable than young rats for evaluation of 5-FU-induced myelotoxicity.  相似文献   

Chemical Characteristics in Stemflow of Japanese Cedar in Japan     

Asami Nakanishi  Hideaki Shibata  Yoji Inokura  Toshio Nakao  Hiroto Toda  Fuyuki Satoh  Kaichiro Sasa 《Water, air, and soil pollution》2001,130(1-4):709-714

To clarify the characteristics in stemflow of Japanese cedar (Cryptomeria japonica), we conducted the annual and extensive observation. We examined the chemistry of bulk and wet deposition, throughfall and stemflow at 26 forested sites in June and September 1998. The each sampling site was broadly distributed in all over the Japanese archipelago. The stemflow pH of Japanese cedar was significantly lower (p<0.01) than precipitation and stemflow of broad-leaved species in both months. There were significant anion deficits in stemflow of Japanese cedar, suggesting that organic anions derived from plant sources play an important role in the stemflow acidity. Our results suggested that the strong stemflow acidity in Japanese cedar was derived from an internal biological characteristic rather than influences of external acidic deposition.  相似文献   

Gross nitrification rates in four Japanese forest soils: heterotrophic versus autotrophic and the regulation factors for the nitrification     

Megumi Kuroiwa  Keisuke Koba  Kazuo Isobe  Ryunosuke Tateno  Asami Nakanishi  Yoshiyuki Inagaki  Hiroto Toda  Shigeto Otsuka  Keishi Senoo  Yuichi Suwa  Muneoki Yoh  Rieko Urakawa  Hideaki Shibata 《Journal of Forest Research》2011,16(5):363-373

Measurements of gross NH ₄ ⁺ and NO ₃ ^? production in forest soils were conducted using the ¹⁵N pool dilution method. Mineral topsoils (0?C10?cm depth) were collected from four forests from northern to southern Japan with a natural climate gradient to elucidate the mechanisms regulating gross nitrification rates in forest soils. Additionally, we attempted to evaluate the relative importance of heterotrophic nitrification in gross total nitrification using acetylene as a specific inhibitor of autotrophic nitrification. Distinct differences were found among sites in the gross rates of NH ₄ ⁺ production (3.1?C11.4?mg?N?kg^?1?day^?1) and gross total nitrification (0.0?C6.1?mg?N?kg^?1?day^?1). The rates of gross heterotrophic nitrification were low in this study, indicating that heterotrophic nitrification is of minor importance in most forest mineral topsoils in Japan. Significant relations were found between gross autotrophic nitrification and gross NH ₄ ⁺ production, soil N, and soil C concentrations, but none was found between gross autotrophic nitrification and soil pH. We determined the critical value of the gross NH ₄ ⁺ production rates for gross autotrophic nitrification under which no gross autotrophic nitrification occurred, as well as the critical soil C/N ratio above which gross autotrophic nitrification ceased. Results show that tight coupling of production and consumption of NH ₄ ⁺ prevents autotrophic nitrifiers from utilizing NH ₄ ⁺ as long as NH ₄ ⁺ availability is low.  相似文献   

Molecular identification of red tide-causing microalga Heterosigma akashiwo strains based on their chloroplast DNA sequences   总被引：1，自引：0，他引：1  

Shin-Ichiro  AKASE  Takeshi  YOSHIKAWA  Noriko  HAYAKAWA  Hiroto  MAEDA  Taizo  SAKATA 《Fisheries Science》2004,70(6):1043-1050

ABSTRACT:   In order to establish genetic signatures for intraspecific identification, parts of the genes rbcL , rbcS and psbA and their intergenic spacer (IGS) regions were amplified by polymerase chain reaction (PCR) from the chloroplast genomes of Heterosigma akashiwo strains isolated from Japan. A transfer RNA-Leu gene trnL and a hypothetical gene cfxQ , which is related to ribulose bisphosphate carboxylase/oxygenase expression, were found in the upstream region of the rbcL gene and in the rbcS-psbA IGS region, respectively. All the gene-coding regions and the IGS regions between rbcL and rbcS showed the same sequences among the strains tested. In contrast, the rbcL upstream regions and the rbcS-cfxQ IGS regions showed some differences such as nucleotide substitutions, duplications and inversions between NIES-5 and the other strains. Based on these sequence data, five genetic signatures were established and their simple and rapid detection by means of strain-specific PCR primers and PCR-restriction fragment length polymorphism techniques was examined. The results suggested the usefulness of these genetic signatures and techniques for the discrimination of H. akashiwo populations.  相似文献   

Differential mechanisms of action of the novel γ‐aminobutyric acid receptor antagonist ectoparasiticides fluralaner (A1443) and fipronil          下载免费PDF全文

Miho Asahi  Masaki Kobayashi  Hiroto Matsui  Kunimitsu Nakahira 《Pest management science》2015,71(1):91-95

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A canine case of gliosis with cyst formation in the posterior fossa     

Kitagawa M  Okada M  Oogushi N  Dei H  Yamamura H  Kanayama K  Sakai T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(7):611-614

A 5-month-old male Great Pyrenees with symptoms of convulsions, circling, and a head tilt was referred to the Animal Medical Center of Nihon University. On a magnetic resonance image (MRI), a cyst in the posterior fossa was noted and a part of the cyst enhanced by gadoteridol. Based on MRI and clinical findings, the patient was tentatively diagnosed with a cyst formation tumor, and an operation to open the cyst and remove the part enhanced by contrast was performed. Postoperatively, the clinical course was good. Pathologically, the removed tissue was diagnosed as a gliosis with cyst formation.  相似文献   

Somaclonal variation in Tricyrtis hirta plants regenerated from 1-year-old embryogenic callus cultures     

Masaru Nakano  Toshikazu Nomizu  Keiko Mizunashi  Mami Suzuki  Shiro Mori  Sachiko Kuwayama  Megumi Hayashi  Hiroto Umehara  Eriko Oka  Hiroyuki Kobayashi  Megumi Asano  Shintaro Sugawara  Hiroki Takagi  Hiroyuki Saito  Masashi Nakata  Toshinari Godo  Yoshihiro Hara  Junji Amano 《Scientia Horticulturae》2006,110(4):366-371

The Liliaceous perennial Tricyrtis hirta, sometimes called ‘Japanese toad lily’, has recently become popular as an ornamental for pot and garden uses. Highly embryogenic callus cultures of this plant predominately consisted of diploid cells but also contained tetraploid cells after 1 year of establishment. In the present study, plans regenerated from the 1-year-old embryogenic callus cultures were subjected to ploidy level analysis and morphological characterization following 3 years of cultivation. Among 37 plants examined, 28 kept the diploid level (2n = 2x = 26) but nine were tetraploid (2n = 4x = 52) as indicated by FCM analysis and chromosome observation. Although no morphological alterations were detected in 26 out of 28 diploid regenerants, the remaining two showed noticeable variations: both were severely dwarf and had crimped leaves and many malformed flowers. The tetraploid regenerants had several horticulturally attractive characteristics compared with the diploid controls, such as longer shoots, thicker stems, and larger flowers. Thus regeneration of tetraploid plants from 1-year-old embryogenic callus cultures offers a possibility to improve the horticultural value of T. hirta, although regeneration of trueness-to-type plants is essential for utilizing the cultures for micropropagation and genetic transformation.  相似文献   

Specific detection of a basidiomycete, Phlebia brevispora associated with butt rot of Chamaecyparis obtusa, by PCR-based analysis     

Hiroto Suhara  Nitaro Maekawa  Takashi Kubayashi  Ryuichiro Kondo 《Journal of Wood Science》2005,51(1):83-88

In order to monitor the basidiomycetous fungus Phlebia brevispora isolated from butt rot of Chamaecyparis obtusa (Japanese cypress) in 1997 in Nagasaki Prefecture, a sensitive polymerase chain reaction (PCR)-based assay was developed to specifically detect the fungus on-site. A species-specific primer for P. brevispora was derived from the internal transcribed spacer (ITS) region (containing 5.8S ribosomal DNA, ITS1 and ITS2) sequences of the fungus. The PCR assay was able to detect down to 1fg DNA (per 1µl PCR reaction mixture) and down to 0.2mg mycelium of P. brevispora (per 1g of decayed wood). The samples for on-site monitoring were collected in 2002 from the decayed tree stump in which P. brevispora had first been isolated. From the decayed tree tissue, P. brevispora could be detected by PCR assay even when its mycelium could not isolated from the tree tissue by culturing. This indicates that the PCR amplification using the specific primer developed here is a useful method for monitoring P. brevispora on-site.  相似文献