The serological grouping of Candida albicans strains isolated in the Kraków province in the years 1963–1965 by means of agar gel diffusion test

Summary One hundred forty sevenCandida albicans strains isolated from different clinical specimens were serologically differentiated. Agar gel diffusion test inBjörklund modification was applied inCandida albicans grouping. Autolysates prepared from the strains under study and from the group A and B standard strains ofHasenclever were used as antigens against anti-Candida albicans group A rabbit immune sera. Among 147 examined strains isolated from 107 patients, 137 strains were classified as belonging to group A and only 10 (9.3 %) strains as belonging to group B.     

微卫星标记对WHBE兔封闭群、日本大耳白兔和新西兰兔的遗传分析

目的分析比较大耳白黑眼兔（WHBE兔）封闭群与日本大耳白兔（Jw兔）、新西兰兔（NZW兔）基因组存在的微卫星结构,研究WHBE兔封闭群的微卫星多态性。方法利用21个微卫星位点,通过微卫星分子标记技术对WHBE兔封闭群、Jw兔和NZW兔进行遗传多样性检测和对比。结果根据初步结果,在21对微卫星引物中筛选出扩增产物稳定并且具有多态性的11对引物。WHBE兔封闭群在每个位点上的等位基因数为3～8个不等,11个位点的平均有效等位基因数为2．0402个,平均杂合度为0．4810;Jw兔在每个位点上的等位基因数为2～8个不等,11个位点的平均有效等位基因数为3．6077个,平均杂合度为0．5039;NZW兔在每个位点上的等位基因数为3～9个不等,11个位点的平均有效等位基因数为2．6537个,平均杂合度为0．5334。WHBE兔封闭群在11个微卫星位点上的平均多态信息含量（PIC）为0．6005,多位点累积个体识别率达到100％,多位点累积非父排除概率（CPE）在双亲信息都是未知情况下的为0．9613,而在得知任一亲本信息的情况下,CPE值高达0．9973。在11个微卫星座位中,9个位点上出现了WHBE兔封闭群特有等位基因,其中在Sat2、Sat5、Sat7、Sat12、Sat13、Sat16、S0144和INRACCDDV0003八个位点上WHBE兔封闭群的特有等位基因为一个,在sat8位点上为两个。结论WHBE兔8个位点的平均杂合度、平均有效等位基因数均比JW兔及NZW兔低,说明WHBE兔群体的基因纯合度高于其他两个品系,具有更优的遗传稳定性。9个WHBE兔特有的等位基因可作为区分WHBE兔封闭群和其它两个品系实验兔的分子标记。     

Rabbit Ileal Loop Response to Strains of Clostridium perfringens

The ligated loop of the rabbit intestine was investigated as a possible experimental model for the study of Clostridium perfringens food poisoning. The method of preparation of the challenge inoculum was important in determining whether a given strain would provoke a response. When cultures were grown for 4 hr at 37 C in Skim Milk (Difco), 14 of 29 type A strains isolated from food-poisoning outbreaks consistently produced exudation of fluid and consequent dilation of the ileal segments. In contrast, 15 of the 18 strains derived from other sources failed to elicit a response. By use of different inoculum preparations, nearly all strains could be made to give at least an occasional positive loop reaction. Diarrhea was not obtained in rabbits by intraluminal injection into the normal ileum or by per os administration of the cultures. Lecithinase, purified and in concentrated culture supernatant fractions, failed to produce a response in the isolated ileal loops.     

Rabbit model of rotavirus infection.

A new small animal model was developed to study parameters of rotavirus infections, including the active immune response. Seronegative New Zealand White rabbits (neonatal to 4 months old) were inoculated orally with cultivatable rabbit rotavirus strains Ala, C11, and R2 and with the heterologous simian strain SA11. The course of infection was evaluated by clinical findings, virus isolation (plaque assay and enzyme-linked immunosorbent assay), and serologic response. All four strains of virus were capable of infecting rabbits as determined by isolation of infectious virus from intestinal contents or fecal samples, by seroconversion, or by a combination of these methods. The responses differed depending on the virus strain used for inoculation. Rabbits remained susceptible to primary infection to at least 16 weeks of age (upper limit examined). Virus excretion in intestinal contents was detected from 6 h to 7 days postinoculation. RNA electropherotypes of inocula and viruses isolated from rabbits were the same in all samples tested. Transmission of Ala virus and R2 virus but not SA11 virus from inoculated animals to uninoculated controls also occurred. In a challenge experiment with Ala virus, 74- and 90-day-old rabbits were rechallenged with Ala 5 weeks after a primary infection with Ala. Virus was excreted in feces from 2 to 8 days after the primary infection but was not excreted after challenge. These results indicate that the rabbit provides an ideal model to investigate both the primary and secondary active immune responses to rotavirus infections and to evaluate candidate vaccines.     

WHBE兔血液蛋白的特性

目的比较大耳白黑眼兔（WHBE兔）与日本大耳白兔（JW兔）和新西澜兔（NZW兔）血液蛋白的多态性,从分子水平了解WHBE兔特殊性状的遗传背景。方法采用聚丙烯酰胺凝胶电泳对WHBE兔、JW兔和NZW兔血液中的前白蛋白（Pr）,后白蛋白（Po）,前转铁蛋白1（Prt1）,前转铁蛋白2（Prt2）,转铁蛋白1（Tf1）,转铁蛋白2（Tf2）,后转铁蛋白（Ptf）,慢α球蛋白（Sag）、血红蛋白（Hbα、Hbβ）和白蛋白（Alb）共11个蛋白位点进行检测。结果Pr、Ptf、Hbα、Hbβ、Alb、Po、Sag和Prt2在所有实验兔个体中的表型一致,而Tf1、Tf2和Prt1的表型在各实验兔品系间存在显著差异。在Tf1位点,NZW兔以BC表型为主,无AA型;JW兔只有AA型,而WHBE兔以AB型为主。在Tf2位点,NZW兔有AA型,而JW兔和WHBE兔无AA型。在Prt1位点,NZW兔无AB、BB和BC表型而有AC表型。NZW兔蛋白位点的平均杂合度大于JW兔和WHBE兔。JW兔与WHBE兔的遗传距离最近。结论Tf1、Tf2和Prt1可作为区分NZW兔、JW兔和WHBE兔的特征标记,并且与WHBE兔特殊性状形成有关。JW兔与WHBE兔的亲缘关系最近。     

兔出血症病毒（RHDV）WHNRH株的分离鉴定及基因组全序列的测定与分析

从发病长毛兔中分离鉴定了兔病毒性出血症病毒WHNRH株。参考GenBank中已登录的RHDV毒株序列对RHDV WHNRH分离株进行了全基因组序列测定与分析。设计5对扩增区段相互重叠的RHDV特异性引物,扩增除5′和3′末端以外的序列,采用设计锚引物的5′RACE方法以及针对RHDV 3′末端的polyA结构设计引物获得了RHDV WHNRH株的5′和3′末端序列。胶回收各PCR产物,连接pMD 18-T克隆载体,测得RHDV WHNRH分离株的基因组全长为7437nt(不包括polyA),与GenBank公布的全部共6株RHDV全基因序列进行同源性比较分析,同源性在89.0%~97.1%之间,ORF1同源性为89.0%~97.1%,编码氨基酸序列的同源性为95.2%~98.7%;ORF2的核酸苷序列同源性为92.1%~97.7%,编码氨基酸序列的同源性为94.1%~96.6%。     

Comparison of Cytocidal and Noncytocidal Strains of Shope Rabbit Fibroma Virus

Seven strains of Shope fibroma virus were compared for their effect on rabbit cells in vitro. All but one of the naturally occurring strains examined in this study produced a similar response in the infected cultures. This consisted of continued cell multiplication together with changes in cell morphology and growth pattern. In contrast, a recently isolated strain of fibroma virus, the M1 strain, was found to produce a gradual cell destruction under the same cultural conditions. A comparison of the cytocidal M1 strain with a representative noncytocidal strain in vitro showed no differences in the rate of multiplication, plaque type, antigenic composition, or heat lability. Only minor differences were found in the tumors produced in rabbits by these strains.     

Enhanced activity of carotid body chemoreceptors in rabbits with heart failure: role of nitric oxide.

An enhanced peripheral chemoreflex has been documented in patients with chronic heart failure (CHF). This study aimed to examine the characteristics of carotid body (CB) chemoreceptors in response to isocapnic hypoxia in a rabbit model of pacing-induced CHF and to evaluate the possible role that nitric oxide (NO) plays in the altered characteristics. The chemosensitive characteristics of the CB were evaluated by recording single-unit activity from the carotid sinus nerve in both an intact and a vascularly isolated preparation. It was found that the baseline discharge under normoxia (intact preparation: arterial PO2 90-95 Torr; isolated preparation: PO2 100-110 Torr) and the chemosensitivity in response to graded hypoxia (PO2 40-70 Torr) were enhanced in CHF vs. sham rabbits. These alterations were independent of the CB preparations (intact vs. isolated). NO synthase inhibition by Nomega-nitro-L-arginine increased the baseline discharge and the chemosensitivity in the intact preparation, whereas L-arginine (10(-5) M) inhibited the baseline discharge and the chemosensitivity in the isolated preparation in sham but not in CHF rabbits. S-nitroso-N-acetylpenicillamine, an NO donor, inhibited the baseline discharge and the chemosensitivity in both CB preparations in CHF rabbits but only in the isolated preparation in sham rabbits. The amount of NO produced in vitro by the CB under normoxia was less in CHF rabbits than in sham rabbits (P < 0.05). NO synthase-positive varicosities of nerve fibers within the CB were less in CHF rabbits than in sham rabbits (P < 0.05). These data indicate that an enhanced input from CB occurs in the rabbit model of pacing-induced CHF and that an impairment of NO production may contribute to this alteration.     

Studies on adhesion, haemagglutination and other biological properties of Vibrio cholerae O139

Abstract The adhesive capabilities of eight Vibrio cholerae O139 epidemic strains to isolated rabbit intestinal epithelial cells (RIEC) were observed to be high similar to those observed with a Vibrio cholerae O1 strain isolated from patients. Toxin production by the strains, measured by accumulation of fluid in rabbit ileal loop model, was high and the toxin was lethal as the animal expired within 6 h. Culture filtrates of the strains exhibited the presence of vascular permeability factor which produce induration and necrosis in the adult rabbit and guinea pig skin. All the strains showed high to moderate haemagglutinin titres against chicken erythrocytes and produced El Tor-like haemolysin. SDS-PAGE of the outer membrane preparation of the strains showed the presence of major protein component at 38 kDa region. The lethality of the toxin, high adhesive activity, shifting of the major outer membrane protein band and production of thermolabile haemolysin on Wagatsuma agar were the major variations of these epidemic strains from V. cholerae O1 and V. cholerae non-O1 strains isolated previously.     

猪链球菌2型对扁桃腺上皮细胞的黏附和侵袭作用

猪链球菌2型(SS2)是重要的人畜共患病病原体,溶菌酶释放蛋白（MRP）是SS2的主要毒力因子之一。用天然表达MRP的江苏分离株HA9801和不表达MRP的上海分离株SH006444,研究SS2对仔兔扁桃腺上皮细胞的黏附和侵袭作用。黏附计数结果表明,HA9801（MRP+）和SH006444（MRP-）均能对扁桃腺上皮细胞高水平黏附。扫描和透射电镜均观察到HA9801的高水平黏附现象,黏附部位是细胞膜和细胞微绒毛,并观察到细胞膜上有链球菌正处于内化过程中。裂解记数结果表明,HA9801有低度侵袭力,SH006444未检测到侵袭力。结果提示,扁桃腺是SS2的定殖器官和感染门户;MRP＋菌株黏附后直接侵入细胞内是其穿过扁桃腺上皮细胞屏障的机制之一。     

Rabbit haemorrhagic disease: applying Occam's razor to competing hypotheses

Rabbit haemorrhagic disease virus (RHDV) is a highly virulent lagovirus endemic in Europe and Australasian populations of the European rabbit, Oryctolagus cuniculus. It has also caused several unexplained disease outbreaks in domestic European rabbits in North America. Non-pathogenic spread of RHDV leading to persistent infection which later reactivated has recently been proposed as the cause of overt disease and death of a pet rabbit in Canada, the first confirmed case of Rabbit haemorrhagic disease in that country. We suggest that there is little evidence to support non-pathogenic spread of virulent RHDV, some evidence that is contradictory, and evidence to support a simpler alternative hypothesis. RHDV can be spread over long distances between sparse rabbit populations by fomites or flying insects. Although highly pathogenic, RHDV can be limited in its spread within rabbit populations, or its presence masked by closely related but non-pathogenic lagoviruses which can provide protection against acute disease. In the absence of any evidence from clinical studies to support reactivation of persistent RHDV infection, the simpler explanation seems more likely to be correct.     

Identification and molecular cloning of a 70 kDa species-specific antigen common to Clostridium difficile

Abstract Three common antigens (CB 1, 2 and 3), characteristic of Clostridium difficile species were identified by immunoblot analysis using homologous and heterologous rabbit antisera, raised against whole cells from 9 distinct strains of C. difficile . A gene library of C. difficile genomic DNA was constructed in Escherichia coli by cloning in Sau 3A-cleaved clostridial DNA fragments into the bacteriophage vector λEMBL3. Out of 3000 plaques screened using the whole cell antisera, 27 clones were positively identified. One of these clones, designated λCd21, expressed high levels of an antigen which could be immunologically identified using whole cell antisera against the 9 C. difficile strains. Antiserum raised against the clone λCd21 identified a 70 kDa antigen (previously named CB1) as demonstrated by immunoblot analysis. Monospecific antiserum against λCd21 recognises the 70 kDa antigen in all 97 strains of C. difficile derived from worldwide sources and does not cross-react with 17 strains from 13 other clostridial species.     

Identification and molecular cloning of a 70 kDa species-specific antigen common to Clostridium difficile

Three common antigens (CB 1, 2 and 3), characteristic of Clostridium difficile species were identified by immunoblot analysis using homologous and heterologous rabbit antisera, raised against whole cells from 9 distinct strains of C. difficile. A gene library of C. difficile genomic DNA was constructed in Escherichia coli by cloning in Sau 3A-cleaved clostridial DNA fragments into the bacteriophage vector lambda EMBL3. OUt of 3000 plaques screened using the whole cell antisera, 27 clones were positively identified. One of these clones, designated gamma Cd21, expressed high levels of an antigen which could be immunologically identified using whole cell antisera against the 9 C. difficile strains. Antiserum raised against the clone gamma Cd21 identified a 70 kDa antigen (previously named CB1) as demonstrated by immunoblot analysis. Monospecific antiserum against gamma Cd21 recognises the 70 kDa antigen in all 97 strains of C. difficile derived from worldwide sources and does not cross-react with 17 strains from 13 other clostridial species.     

Phenotypic, antigenic, and molecular characterization of Pasteurella piscicida strains isolated from fish.

We compared Pasteurella piscicida strains isolated from different fish species in several European countries with strains isolated in Japan and the United States. The taxonomic analysis revealed that, regardless of the geographic origin and source of isolation, all the strains exhibited the same biochemical and physiological characteristics. Serological assays with different rabbit antisera demonstrated a high level of antigenic similarity among strains, with cross-agglutination titers of 20,480 to 40,960. This serological homogeneity was supported by the lipopolysaccharide (LPS) and membrane protein profiles. All the P. piscicida strains had the same electrophoretic LPS pattern, showing O side chains with a ladder-like structure, and shared at least four major outer membrane proteins, of 20, 30, 42, and 53 kDa. Western blot (immunoblot) analysis with LPS and protein indicated that all the P. piscicida strains are immunologically related. In addition, the chromosomal DNA fingerprint patterns obtained for the European strains with the enzymes EcoRI and BamHI were practically identical to those of the Japanese and U.S. strains. Although some differences were found in the plasmid profiles of P. piscicida, a large number of strains possessed in common plasmid bands of 20 and 7 MDa. In addition, a plasmid of 50 MDa was present in the majority of the European strains. Restriction endonuclease analysis demonstrated the genetic homology of the plasmid bands shared by most of the European strains. All the P. piscicida strains had the same drug resistance patterns, indicating that a correlation between plasmid carriage and resistance to a specific antimicrobial agent cannot be established. The high levels of phenotypic, serological, and genetic homogeneity found among the P. piscicida strains should facilitate the development of DNA probes with diagnostic purposes as well as the design of effective vaccines.     

Phenotypic, antigenic, and molecular characterization of Pasteurella piscicida strains isolated from fish.

We compared Pasteurella piscicida strains isolated from different fish species in several European countries with strains isolated in Japan and the United States. The taxonomic analysis revealed that, regardless of the geographic origin and source of isolation, all the strains exhibited the same biochemical and physiological characteristics. Serological assays with different rabbit antisera demonstrated a high level of antigenic similarity among strains, with cross-agglutination titers of 20,480 to 40,960. This serological homogeneity was supported by the lipopolysaccharide (LPS) and membrane protein profiles. All the P. piscicida strains had the same electrophoretic LPS pattern, showing O side chains with a ladder-like structure, and shared at least four major outer membrane proteins, of 20, 30, 42, and 53 kDa. Western blot (immunoblot) analysis with LPS and protein indicated that all the P. piscicida strains are immunologically related. In addition, the chromosomal DNA fingerprint patterns obtained for the European strains with the enzymes EcoRI and BamHI were practically identical to those of the Japanese and U.S. strains. Although some differences were found in the plasmid profiles of P. piscicida, a large number of strains possessed in common plasmid bands of 20 and 7 MDa. In addition, a plasmid of 50 MDa was present in the majority of the European strains. Restriction endonuclease analysis demonstrated the genetic homology of the plasmid bands shared by most of the European strains. All the P. piscicida strains had the same drug resistance patterns, indicating that a correlation between plasmid carriage and resistance to a specific antimicrobial agent cannot be established. The high levels of phenotypic, serological, and genetic homogeneity found among the P. piscicida strains should facilitate the development of DNA probes with diagnostic purposes as well as the design of effective vaccines.     

一株高毒力致病杆菌CB6的鉴定

从北京郊区果园采集的小卷蛾斯氏线虫（Steinernema carpocapsae）肠道内分离到一株具有较强杀虫和抑菌活性的致病杆菌菌株CB6。形态特征及生理生化特征测定结果表明,CB6菌株与致病杆菌属（Xenorhabdus）中的嗜线虫致病杆菌（X. nematophila）种的特征基本一致。测定了该菌株的16S rRNA序列并根据16S rRNA序列构建了系统发育树;在系统发育树中,CB6菌株与嗜线虫致病杆菌其他4个菌株形成一个类群,序列同源性大于99%。但CB6菌株的酪氨酸酶、脂酶（蛋黄）的产生、核糖产酸等生化特征与嗜线虫致病杆菌种内的其他菌株存在一定的差异,且具有更强的杀虫和抑菌活性。因此认为CB6菌株是嗜线虫致病杆菌的一个变种,命名为嗜线虫致病杆菌北京变种（X. nematophila var. pekingensis）。     

Rabbit liver transglutaminase: physical, chemical, and catalytic properties.

Transglutaminase (R-glutaminyl-peptide:amine alpha-glutamyl-yltransferase [EC 2.3.2.13]) has been purified to apparent homogeneity from extracts of rabbit liver. The enzyme is a single polypeptide chain of approximately 80 000 molecular weight containing one catalytic site per molecule. That the isolated enzyme is the rabbit counterpart of the well-characterized guinea pig liver transglutaminase is evidenced by the similarities in their amino acid compositions and in their enzymic activities toward several substrates, together with the fact that the isolated rabbit enzyme is immunologically distinct from both rabbit plasma and rabbit platelet blood coagulation factor XIII. A striking difference between the catalytic activities of the rabbit and guinea pig enzymes is the low activity of rabbit transglutaminase for hydroxylamine incorporation into benzyloxycarbonyl-L-glutaminylglycine, a reaction for which the guinea pig enzyme shows a high reactivity. This finding reveals the cause of error in an earlier report (Tyler, H.M., and Laki, K. (1967) Biochemistry 6, 3259) that rabbit liver contains little, if any, of the enzyme. Preparation of, and analytical data on, several glutamine-containing peptide derivatives used in this study are reported here.     

兔胚胎神经干细胞的分离、培养和鉴别

目的：研究兔胎脑神经干细胞体外生长特性,为探讨神经干细胞的临床应用及神经系统的发育奠定基础。方法：采用含碱性成纤维细胞生长因子（bFGF）和表皮细胞生长因子（EGF）的N2无血清培养技术,取18天龄兔胚胎脑组织,分离神经干细胞,并观察分离的细胞体外培养、增殖、分化潜能,免疫组化鉴定。结果：从18天龄兔胎脑皮质和纹状体中成功分离出具有自我更新和多分化潜能的神经干细胞,在无血清培养时细胞呈半贴壁状态生长,形成神经球,可传代。细胞呈Nestin免疫反应阳性;在含血清培养基中培养时则分化,分化后的细胞表达神经元细胞、星形胶质细胞和少突胶质细胞的特异性抗原。结论：来自兔胎脑神经干细胞能在体外培养、增殖并保持传代能力。无血清N2EGF、bFGF培养基有利于兔胎脑神经干细胞的存活和增殖,含血清培养基能诱导兔胎脑神经干细胞分化。