Characterization of Pasteurella multocida isolated from rabbits in Canada

In a survey for the somatic and capsular serotypes of Pasteurella multocida present in domestic rabbits in Canada, but mainly in Ontario, samples were obtained from research facilities, commercial rabbitries and from abattoir and necropsy specimens. Sources of isolates were upper respiratory tract infections, localized bronchopneumonias , acute fibrinous pneumonias, abscesses and otitis media. Of 59 isolates obtained, 47.0% were type 12:A, 30.5% 3:D and 12.0% were 3:A. Less common types were 12(4):A, 12:D, 4(12):A and 3:untypable. Somatic group 3 was most commonly isolated from acute pneumonic disease, while serogroup 12:A was most commonly found in upper respiratory tract infections and in localized chronic bronchopneumonia. Two serotypes of P. multocida were isolated from four pneumonic lungs collected from abattoir specimens. Most isolates were susceptible to the commonly used antibiotics.     

Capsular and somatic types of Pasteurella multocida from rabbits

Capsular and somatic serotyping was performed on 79 cultures of Pasteurella multocida from rabbits. Of these isolates, 74 were capsular type A as determined by the staphylococcal hyaluronidase decapsulation test and five were type D by the acriflavine flocculation test. Somatic type 12 was the dominant serotype, and the remainder (type 1, 3, 4 and 11) were less frequent as determined by the gel diffusion precipitin test. This report is in general agreement with other recent reports with rabbit isolates and collectively they provide important serotype and epizootiological information that will be useful in the control and prevention of rabbit pasteurellosis.     

Pasteurella multocida osteomyelitis of the cervical spine in a patient on chronic haemodialysis

Osteomyelitis due to Pasteurella multocida has been frequently documented but virtually all previous cases have resulted from direct inoculation of the organism or contiguous spread of local infection, following animal bites or scratches. Infections often occur in patients with serious underlying illnesses. Haematogenous osteomyelitis due to P multocida has very rarely been reported particularly in patients with chronic renal failure. We describe a patient on chronic haemodialysis who developed an acute febrile illness, two months following a monkey bite, caused by haematogenous cervical vertebral osteomyelitis due to P multocida.     

Preliminary studies with a live streptomycin-dependent Pasteurella multocida and Pasteurella haemolytica vaccine for the prevention of bovine pneumonic pasteurellosis

Twelve Pasteurella-free Holstein-Friesian calves were used in a study to test the efficacy of a live streptomycin-dependent Pasteurella multocida A:3 and streptomycin-dependent Pasteurella haemolytica A1 vaccine. The calves were inoculated intramuscularly twice at 14-day intervals with either the streptomycin-dependent vaccine, containing 1 X 10(6) colony forming units/mL P. multocida and 4 X 10(8) colony forming units/mL P. haemolytica, commercial bacterin, or phosphate buffered saline. Two weeks following the second vaccination, all calves were challenged by intranasal inoculation of 10(8) TCID50/4.0 mL infectious bovine rhinotracheitis virus followed three days later by intratracheal injection with 2.3 X 10(7) colony forming units/mL of a 16 hour culture of P. multocida A:3 and 2.6 X 10(8) colony forming units/mL of an 8 hour culture of P. haemolytica A1. Seven days after challenge with Pasteurella, calves were killed for collection of tissues at necropsy. Each calf was given a score based on macroscopic and microscopic lesions. The scores for the calves receiving live vaccines were significantly lower (p less than 0.025) than those for the controls. Also, the calves receiving live vaccines had a significant (p less than 0.05) increase in the level of serum antibody to P. haemolytica. The results of this preliminary study showed that the streptomycin-dependent vaccine offered better protection than the commercial bacterin against a virulent homologous challenge.     

Pasteurella multocida infection in the domestic rabbit: immunization with a streptomycin-dependent mutant

Fourteen Pasteurella multocida-free rabbits were inoculated intranasally with a streptomycin-dependent mutant of P. multocida serotype 12:A. Vaccinations with approximately 10(8) colony forming units were done on days 0, 14 and 28. Two weeks later the animals were separated into groups, which included 12 rabbits divided into two control groups of six unvaccinated Pasteurella-free animals. Seven vaccinated rabbits were challenged intranasally with the homologous virulent parent strain and the other seven vaccinates were challenged with a virulent strain of serotype 3:A. Rabbits were necropsied two weeks later. The vaccinated group challenged with the parent strain showed a more rapid nasal clearance of the organism than the vaccinated group challenged with the heterologous strain. However, the number of positive cultures of P. multocida recovered from tissues post-challenge were similar in vaccinated and control animals. In a significant number of animals, vaccination with serotype 12:A induced detectable antibody production to somatic antigens of both 12:A and heterologous strain 3:A.     

肝脾破裂术中自体血液回输32例临床分析

目的：评价肝脾破裂术中自体血液回输的临床价值,为自体血液回输的合理应用提供参考。方法：采用M9W-3000P3000P型血液回收机对32例肝脾破裂患者进行术中自体血回输,并在术前、术后进行血常规、凝血三项检测。结果：本组平均每例患者回输血液1150ml,死亡2例,无其他严重并发症发生,回输后红细胞（RBC）、血红蛋白（Hb）、血小板（PLT）均有了明显改善[（3．82±0．85）×10^12/L vs（3．53±0．71）×10^12/L;（112．93±24．12）g/L vs（106．86±21．38）g/L;（218．57±108．6）×10^9／L vs（192．35±80．34）×10^9/L]（P=0．025、0．012、0．036）。凝血酶原时间（PT）和活化部分凝血活酶时间（Am）术前与术后24h比较,差异无统计学意义（P=0．852）,均达到了正常水平。本组术后纤维蛋白原（FIB）平均值[（3．41±1．53）g/L]高于术前[（2．54±1．64）g／L]（P=0．021）。结论：自体输血是血液保护的主要组成部分,可提高抢救成功率,又可减少输注异体血造成的经济负担与不良反应,且对患者的血常规与凝血指标有很大改善,值得推广应用。     

Production and characterization of streptomycin dependent mutants of Pasteurella multocida from bovine haemorrhagic septicaemia

A large number of streptomycin dependent mutants were produced from bovine haemorrhagic septicaemia strains of Pasteurella multocida. The mutants required a minimum concentration of 25-50 microgram/mL streptomycin for growth and tolerated a concentration of 200 mg/mL. These mutants were avirulent to mice, when inoculated alone, but some mutants killed mice when inoculated with streptomycin. Biochemically all mutants were uniform and similar to the wild type. Most mutants were stable, but a few produced streptomycin independent revertants. The rate of reversion varied with each mutant. Most revertants were highly virulent for mice, some totally avirulant and a few relatively avirulent.     

Molecular analysis of Pasteurella multocida strains isolated from fowl cholera infection in backyard chickens

Objective

To characterize Pasteurella isolated from backyard chickens using whole cell protein lysate profiles and random amplified polymorphic DNA (RAPD) techniques to show their genetic relationship because Pasteurella multocida (P. multocida) is an important cause of fatal infections in backyard chickens.

Methods

Twenty one P. multocida isolates were recovered previously from clinical cases of fowl cholera belonging to individual owners and phenotypically analyzed using biochemical tests and serotyping were used for the genetic characterization.

Results

Phylogenetic study based on both methods revealed that the recovered population of P. multocida isolated from backyard chickens differs markedly, constituting a well-separated cluster and appearance of 3 distinguishing lineages with greater discrimination shown by RAPD-PCR that resulted in two suclusters in cluster A and three subclusters in cluster B and were related greatly with capsular serogroups for the examined strains. The whole cell protein revealed the presence of dominant protein bands at approximately 41 and 61 kDa in all of the examined isolates that may be a virulent proteins share in the increasing of its pathogenicity. Clear distinctive bands ranged from 123 to 1 554 bp.

Conclusions

Based on the previous findings, there are three spreading clusters that may indicate the association of a small number of P. multocida variants with the majority of cases suggesting that certain clones of P. multocida are able to colonize the examined backyard chickens. Also, the ease and rapidity of RAPD-PCR support the use of this technique as alternative to the more labour-intensive SDS-PAGE system for strain differentiation and epidemiological studies of avian P. multocida. Further application of RAPD technology to the examination of avian cholera outbreaks in commercially available flocks may facilitate more effective management of this disease by providing the potential to investigate correlations of P. multocida genotypes, to identify affiliations between bird types and bacterial genotypes, and to elucidate the role of specific bird species in disease transmission.     

Pneumonia in calves produced with aerosols of Pasteurella multocida alone and in combination with bovine herpesvirus 1

Pathological changes in respiratory tracts were studied in 30 calves following exposure to aerosols of Pasteurella multocida or to bovine herpesvirus 1 and P. multocida. Two groups of five calves were exposed to aerosols of one of two types of P. multocida only, which produced lobar pneumonia in one calf of each group. Another five groups of four calves were exposed to aerosols of bovine herpesvirus 1 and four to seven days later to one of the two types or one sub-type of P. multocida. Extensive necropurulent lesions were produced throughout the respiratory tract with each type of P. multocida in all four calves in three groups but none in the remaining two groups. The pathological changes differed from those produced following similar exposures to bovine herpesvirus 1 and P. haemolytica, in that the exudate in air passages and alveoli was more purulent and streaming (oat) cells and large mononuclear eosinophilic granulocytes were absent. This is the first report of experimental respiratory disease in cattle as a result of aerosol exposure to P. multocida alone or in combination with bovine herpesvirus 1.     

Morphological changes of blood spleen barrier in portal hypertensive spleen

The pathogenesis of hypersplenism and the immune function of the spleen in patients with portal hypertension （PH） remain obscure. This study aimed to evaluate the morphological changes of blood spleen barrier in spleen with hypersplenism due to PH and provide evidence for an in-depth investigation of the immune function of the spleen with hypersplenism and the mechanism of hypersplenism. Methods Spleen samples from 12 portal hypertensive patients and 4 patients with traumatic ruptures of spleen were examined. The samples of spleen were made into pathological sections, stained with Masson trichrome stain, Gomori stain, and CD68, CD34 immunohistochemistry, and were examined microscopically for the changes in the distribution of collagen fibers, reticular fibers, macrophages, and vascular endothelial cells. The changes in ultrastructure of macrophages and endothelial cells in marginal zone were also evaluated by transmission electron microscopy. Results As compared to the normal spleen, the density of macrophage in the PH spleen was decreased, but the macrophages were mainly located in the marginal zone and distributed around the splenic corpuscle, with many villi and pseudopodium-like protrusion on the cell surface. The accrementition of collagen fibers was obvious around the splenic corpuscle and central artery. The increased reticulate fibers encircled the splenic corpuscle with more connection between the fibers. The vascular endothelial cells were in diffused distribution, without any regionality in PH spleen, but the vessel with enlarged lumina increased in red pulp. Conclusions The morphological changes of the blood spleen barrier can be one of the pathological fundaments for the abnormality of the immune function and the increased destruction of blood cells located in the spleens of patients with PH However. this still entails clarification.     

疏肝、健脾、疏肝健脾方对肝郁脾虚证模型大鼠T3、T4、TRH、TSH的影响

目的 比较疏肝、健脾、疏肝健脾方对肝郁脾虚证模型大鼠甲状腺功能的影响.方法 大鼠随机分为正常对照、肝郁脾虚证、柴胡疏肝散、四君子汤、柴疏四君汤5组,每组12只.后4组大鼠采用慢性束缚+过度疲劳+饮食失节法,连续4周造模,正常对照组不予处理.其中3个中药干预方组分别于造模第2周末,按10 mL/kg给予相应方药灌胃,连续2周;模型组和正常对照组给予等量蒸馏水.于实验第29天,处杀各组大鼠,测定血清三磺甲腺原氨酸(T3)、四磺甲腺原氨酸(T4)、促甲状腺激素释放激素(TRH)、促甲状腺激素(TSH).结果 与正常组相比,模型组大鼠血清T3、T4、TRH、TSH均见显著性降低(P<0.05).与模型组相比,柴胡疏肝散、四君子汤、柴疏四君汤3组大鼠血清T3、T4均呈显著性升高(P<0.05);柴疏四君汤组血清TRH、TSH呈显著性升高(P<0.05).结论 肝郁脾虚证模型大鼠存在丘脑-垂体-甲状腺轴的功能低下,柴胡疏肝散、四君子汤、柴疏四君汤对肝郁脾虚证模型的甲状腺功能均有不同程度的改善作用,其中以柴疏四君汤的作用最佳.疏肝健脾方与肝郁脾虚证之间具有更高的关联性.     

B型超声在肝胆脾肾疾病诊断中的价值

目的探讨B型超声检查在健康人群疾病监测的重要性。方法应用B型超声对琼海市1428名健康检查中对肝胆脾肾疾病的结果分析。结果总检出率为47.48%（678/1428）,年龄越大检出率越高,男性高于女性,病种分布以可疑脂肪肝检出率最高,结石中以肾结石最高,胆结石次之。肝囊肿,肾囊肿,胆囊息肉等检出率也较高。结论 B型超声检查是早期发现疾病的重要手段。     

Pulmonary recruitment of neutrophils and bacterial clearance in mice inoculated with aerosols of Pasteurella haemolytica or Staphylococcus aureus

Pulmonary alveolar macrophages are considered to be the main phagocytic cell of the pulmonary defense mechanism. However recent studies indicate that neutrophils may also participate in the defense against inhaled bacteria. The aim of this investigation was to study in mice the correlation between numbers of phagocytic cells in the bronchoalveolar space and the pulmonary clearance of bacteria. White mice were exposed to aerosols of Pasteurella haemolytica (n = 129) or Staphylococcus aureus (n = 129) in three different experimental replicates. Another group of mice (n = 22) was sham exposed to an aerosol of sterile phosphate buffered solution in a single replicate. Animals were sacrificed at various times postaerosolization. The numbers of neutrophils and alveolar macrophages in lung lavages and the pulmonary bacterial clearance rates were determined and statistically analysed. No significant differences (p greater than 0.05) were observed in the rates of pulmonary clearance between the two genera of bacteria, but P. haemolytica had a significant (p less than 0.05) replicate effect. The number of alveolar macrophages was not significantly affected by either bacteria or phosphate buffered solution. Exposure to P. haemolytica resulted in dramatic, significant (p less than 0.01) but transient increases in neutrophils in the bronchoalveolar space as well as a significant (p less than 0.01) increase in the weights of lung. The correlation between neutrophils and clearance was positive for P. haemolytica but negative for S. aureus. These results indicate that both species of bacteria are rapidly eliminated from the lung despite a rather different cellular response.     

Brugada综合征并肝胆脾转位1例

患者，男性，53岁。因发作性胸闷、胸痛3h就诊当地医院。3h前在看电视时突发胸痛、胸闷伴心悸、心前区压榨感及出汗。当时测血压60／40mmHg,神志清楚，呼吸平稳，双肺底闻及少许细湿性罗音，心率48次／min，律齐，各瓣膜听诊区无杂音。腹部检查无异常。心电图示：窦性心动过缓(48次／min)，PR间期1．44s，QRS波时间1．08s，Q-T间期3．56s,V1、V2导联呈QS波，V1导联ST抬高0．15mV，V2导联ST段鞍背样抬高0．4mV，V3导联斜形抬高0.3mV。     

肝硬化合并脾功能亢进病人肝移植术后脾静脉血流动力学及外周血细胞变化的观察

目的 评价肝移植术中是否需保留脾脏。方法 应用彩色多普勒超声测量术前及术后第1、2及4周35例肝硬化合并脾亢病人脾脏的长径、厚径及脾门静脉管径、平均血流速度及峰值血流速度等并进行比较。同时期测量病人肝固有动脉管径及峰值血流速度、门静脉管径厦血流速度，检测病人外周血细胞计数。结果 术后病人脾脏缩小、脾门静脉平均血流速度及峰值血流速度、门静脉血流速度增加，外周血细胞计数上升，与术前相比有统计学差异（P〈0.05）。结论 肝移植术后脾功能亢进症状得到部分改善，这些症状的改善是否继续或有反复仍需进行长期的观察和研究。     

地塞米松对大鼠肝脾细胞凋亡的影响

目的探讨地塞米松对大鼠肝脾等器官淋巴细胞的影响和对机体免疫抑制作用的机制。方法将20只Wistar大鼠随机分成两组,每组10只,实验组每天腹腔注射地塞米松3 mg/(kg.d),3 d后称大鼠体重、脾湿重、肝湿重。用流式细胞仪分析Annexin V/PI双染后脾细胞的凋亡率。结果实验组体重、脾湿重明显减轻(P<0.001),肝重改变不明显(P=0.75),脾细胞的凋亡率为(34.9±5.8)%,较对照组的凋亡率(0.71±0.09)%显著高(P<0.01)。结论地塞米松促进大量淋巴细胞凋亡是其抑制机体的免疫功能的一种重要机制。     

肝郁脾虚证大鼠血细胞和脏器指数改变的实验研究

目的探讨实验条件下肝郁脾虚证大鼠各类血细胞和脏器指数的改变情况。方法采用夹尾激怒、束缚应激、过度疲劳与饮食失节的复合方法复制肝郁脾虚证动物模型,检测对照组和2周、6周、9周模型组雄性大鼠外周血象和胸腺、肾上腺、肝、脾等脏器指数。结果外周血象检测结果显示,与空白对照组比较,肝郁脾虚证大鼠2周组白细胞和中性粒细胞数量升高(P<0.05或P<0.01),9周组红细胞数量、血红蛋白含量和淋巴细胞数量降低(P<0.05);脏器指数检测结果显示,与空白对照组比较,肝郁脾虚证大鼠6周、9周组胸腺指数降低(P<0.01),9周组肾上腺、脾脏和肝脏指数升高(P<0.05)。结论肝郁脾虚因素会影响机体的血液系统,机体遭受应激刺激时虽然短期能使中性粒细胞的数量增加以对抗伤害,增强抵抗力,但长期肝失疏泄、脾失健运导致神经-内分泌-免疫网络紊乱,造成贫血和淋巴细胞数量减少,机体运氧能力和抵抗力降低。