Failure of embryos from bluetongue infected cattle to transmit virus to susceptible recipients or their offspring

Sixty heifers were infected with bluetongue virus (BTV) by the bites of the vector and by inoculation with insect origin virus. During the acute and convalescent stages of the infection, embryos were collected nonsurgically from these animals and washed according to the recommendations of the International Embryo Transfer Society (1). No BTV was isolated from 77 of these embryos when they were inoculated onto cell culture and into embryonating chicken eggs. There was no evidence of lateral BTV transmission when 231 of these embryos were transferred into susceptible recipients, nor was there evidence of vertical BTV transmission to the 88 calves resulting from these transfers. Another six donors that were assumed to have recovered from a natural infection of BTV, were added to the study to increase the probability of obtaining embryos from a persistently infected BTV carrier. However, it was determined later that these animals had not been infected with BTV but with the closely-related epizootic hemorrhagic disease virus (EHDV). Embryos were collected from these donors and washed as above. Neither BTV nor EHDV was isolated from 26 of these embryos by the inoculation of cell culture and embryonating chicken eggs. There was no evidence of lateral BTV or EHDV transmission to recipients of 15 of these embryos or of vertical BTV or EHDV transmission to the resulting 7 calves. However, two recipients of embryos from one of these donors developed antibodies to BTV 6 to 9 months after transfer. Passive antibodies to BTV were also detected in their calves. There is good evidence that these two recipients acquired BTV from natural exposure to infected insect vectors and not from the transferred embryos.     

Serologically detected lymphocyte antigens in Holstein cattle1

Lymphocytes from 103 Holstein cattle were tested with 11 antilymphocytotoxic sera. Four of these sera were produced by whole blood immunization; these generally yielded lymphocytotoxicity against a large number of animals in each test panel. The majority of the sera were collected from parous cows which had never been immunized. Observations about this latter group of sera are (1) lymphocyte antibodies may occur by alloimmunization in foetal-maternal interaction, (2) normal sera from non-immunized parous cows generally had a narrower specificity of antibodies than from parous cows immunized with blood from unrelated animals and in some cases these antisera may be monospecific, and (3) these sera from parous cows are easy to obtain without the need for laborious immunizations. Analysis of these lymphocytotoxic sera indicate several reagents were obtained which possessed different antibodies; these were useful in detecting polymorphism of cattle lymphocyte antigens. Using these 11 sera, an analysis of the reactions patterns among 103 Holsteins, including parent-offspring data resulted in the postulation of several alleles. These data suggest that cattle lymphocyte antigens are very polymorphic and inherited.     

Serologically detected lymphocyte antigens in Holstein cattle

Lymphocytes from 103 Holstein cattle were tested with 11 antilymphocytotoxic sera. Four of these sera were produced by whole blood immunization; these generally yielded lymphocytotoxicity against a large number of animals in each test panel. The majority of the sera were collected from parous cows which had never been immunized. Observations about this latter group of sera are (1) lymphocyte antibodies, may occur by alloimmunization in foetal-maternal interaction, (2) normal sera from non-immunized parous cows generally had a narrower specificity of antibodies than from parous cows immunized with blood from unrelated animals and in some cases these antisera may be monospecific, and (3) these sera from parous cows are easy to obtain without the need for laborious immunizations. Analysis of these lymphocytotoxic sera indicate several reagents were obtained which possessed different antibodies; these were useful in detecting polymorphism of cattle lymphocyte antigens. Using these 11 sera, an analysis of the reactions patterns among 103 Holsteins, including parent-offspring data resulted in the postulation of several alleles. These data suggest that cattle lymphocyte antigens are very polymorphic and inherited.     

Diversity of Aquatic Actinomycetes in Lakes of the Middle Plateau, Yunnan, China

A total of 749 sediment and water samples were collected from 12 lakes of the Middle Plateau of Yunnan from 1983 to 1993. The diversity and biological characteristics of the aquatic actinomycetes in these lakes were studied. Sixteen genera of actinomycetes were isolated from these samples. Micromonospores assumed a notable dominance (from 39 to 89%) in the actinomycete populations of these lake sediments. Streptomycetes were the second most abundant organisms. The diversity and counts of actinomycetes varied with the season. Thermophilic actinomycetes have a wide distribution in these lakes, but their counts were smaller. The cell wall compositions of certain Micromonospora and Streptomyces strains from an alkaline lake revealed an unusual combination of glycine and isomers of diaminopimelic acid. It seems that aquatic actinomycetes play a significant role in the decomposition of organic substances, including some toxic compounds such as phenol, in these lakes. It also appears that aquatic actinomycetes are one of the important resources for screening useful enzymes and metabolites.     

The histones of the ciliated protozoan Stylonychia mytilus

Histones were extracted from pure macronuclei, micronuclei and macronucleus anlagen and from chromatin which was isolated from these different nuclear fractions. Analysis of these preparations by polyacrylamide gel electrophoresis showed differences in electrophoretic patterns between the histones of these nuclei.     

Genetic Identification of Grey Mullet Species (Mugilidae) by Analysis of Mitochondrial DNA Sequence: Application to Identify the Origin of Processed Ovary Products (Bottarga)

Mitochondrial DNA sequencing was used to identify and distinguish four species of commercially important Mediterranean grey mullets. Partial cytochrome b and D-loop sequences were obtained from the four fish species, and these were used to perform phylogenetic analysis and to determine species-specific DNA fingerprints. Species-specific amplification primers were designed from these fingerprints, and these were used to characterize the species origin of several samples of commercial, processed mullet ovary products. In addition to differentiating between food products from different species, this method is also sensitive enough to distinguish food products from mullets of the same species from different regions.     

Nuclear ribonucleoprotein complexes of amphibian liver. II. Changes in the protein moiety during development.

Ribonucleoprotein complexes composed of small molecular weight nuclear RNA (4--9 S) and proteins were isolated from hepatic nuclei of Rana catesbeiana (bullfrog) and the protein moiety of this nuclear ribonucleoprotein complex compared during different stages of development. SDS-polyacrylamide gel analysis of premetamorphic tadpoles and adult frog nuclear ribonucleoprotein complexes revealed that while the protein profiles of these two particles were very similar polypeptides of 47,000, 70,000, and 11,000 molecular weight were present in significantly higher concentrations in the frog ribonucleoprotein complexes. Comparison of the chromatin proteins isolated from these two developmental stages demonstrated that these three polypeptides of frog ribonucleoprotein were not contaminants from chromatin. Since these three polypeptides could not be preferentially extracted from the frog ribonucleoprotein complex by 0.5 M KCl or 1 M urea, it was unlikely that these polypeptides were bound nonspecifically to the ribonucleoprotein particle. Polypeptide analysis of the nuclear ribonucleoprotein complexes isolated from tadpoles immersed in the thyroid hormone L-thyroxine revealed an increase in two polypeptides of 37,000 and 45,000 molecular weight during metamorphosis. The absence of reduced amount of these two polypeptides in either the premetamorphic tadpole or adult frog demonstrated that their presence in Rana catesbeiana nuclear ribonucleoprotein was transient during development and specifically associated with tadpole metamorphosis. We conclude from these experiments that the nuclear ribonucleoprotein complex is a dynamic structure during Rana catesbeiana development and that specific changes in its protein composition are associated with discrete stages of amphibian development.     

大熊猫幼兽腹泻粪便分离出的轮状病毒鉴定

11 只5 ～ 11 月龄的断奶大熊猫幼兽先后患一种急性传染性、顽固性腹泻病,1 只大熊猫幼兽在发病4 d 后死亡,相同饲养条件下由母兽哺育的同龄大熊猫幼兽未见发病。取发病大熊猫幼兽粪便、血液以及呕吐物进行细菌学和寄生虫学检查,未检出病原;用轮状病毒粪便抗原ELISA 快速诊断,受检的8 只大熊猫幼兽腹泻便都多次检出阳性结果。采集发病大熊猫的病料进行病毒病原分离,从腹泻大熊猫幼兽的粪便中分离出病毒颗粒,通过电镜形态、理化特性和中和试验鉴定,确认分离病毒为轮状病毒。      

Ultrastructural and phylogenetic studies on Blastocystis isolates from cockroaches

Four Blastocystis isolates from cockroaches were established and these isolates were morphologically confirmed as Blastocystis organisms by light and/or electron microscopy. As these isolates were morphologically indistinguishable from Blastocystis isolated from other animals, phylogenetic analyses were conducted using their small subunit ribosomal RNA genes. A analyses of these sequences with previously reported ones that had been classified into nine Blastocystis clades indicated the presence of a new clade that comprised only Blastocystis organisms from cockroaches (clade X). A clade comprised of amphibian and reptilian Blastocystis organisms (clade IX) was located at the basal position of the Blastocystis tree together with the common ancestor of Proteromonas and Protoopalina, clade X emerged after the divergences of these two basal clades and its branching position was clearly supported by bootstrap analysis.     

Genomic polymorphism in consecutive generation rice plants from seeds on board a spaceship and their relationship with space HZE particles

Dry rice seeds (Oryza sativa,subspecies indica)were sandwiched between nuclear track detectors,aboard the Chinese spaceship Shenzhou-3 for seven days.The seeds were recovered and the genomic polymorphism in 201 plants developed from these seeds was studied using random amplified polymorphism DNA analysis.When compared with plants from ground-based control seeds,the genomic polymorphic bands were amplified in 30.2% of the plants from the seeds exposed in space.The results for sequencing and SNP analyses of the polymorphic bands verified the single nucleotide variations in these plants.Genomic polymorphisms in the consecutive generations of individual plants of the seeds from space were also discovered.Seven seeds receiving hits of HZE (high atomic number and high energy)particles from space were selected for further analyses and variable genomic polymorphisms were detected in all plants that developed from these seeds.Among them,the embryos of three seeds were hit at least once,and mutants with significant changes in agronomic traits were only found in later generations of these seeds.This result implies that the HZE particles of space are effective in inducing the changes of plant genome of inherited phenotypes.     

Multiple splicing factors are released from endogenous complexes during in vitro pre-mRNA splicing.

Pre-mRNA splicing occurs in a macromolecular complex called the spliceosome. Efforts to isolate spliceosomes from in vitro splicing reactions have been hampered by the presence of endogenous complexes that copurify with de novo spliceosomes formed on added pre-mRNA. We have found that removal of these large complexes from nuclear extracts prevents the splicing of exogenously added pre-mRNA. We therefore examined these complexes for the presence of splicing factors and proteins known or thought to be involved in RNA splicing. These fast-sedimenting structures were found to contain multiple small nuclear ribonucleoproteins (snRNPs) and a fragmented heterogeneous nuclear ribonucleoprotein complex. At least two splicing factors other than the snRNPs were also associated with these large structures. Upon incubation with ATP, these splicing factors as well as U1 and U2 snRNPs were released from these complexes. The presence of multiple splicing factors suggests that these complexes may be endogenous spliceosomes released from nuclei during preparation of splicing extracts. The removal of these structures from extracts that had been preincubated with ATP yielded a splicing extract devoid of large structures. This extract should prove useful in the fractionation of splicing factors and the isolation of native spliceosomes formed on exogenously added pre-mRNA.     

Development of ten highly polymorphic microsatellite markers for Sunbirds (Aves: Nectariniidae) with broad cross-amplification utility in at least eight species

We describe the isolation of ten microsatellite loci from the Rwenzori Double-collared Sunbird using an enrichment protocol. All loci were variable with the number of alleles ranging from 5 to 13, and observed heterozygosity ranging from 0.500 to 0.929. Nine of these loci were screened on a panel of seven additional Sunbird species from three genera. All nine were successfully amplified and remained highly variable. Given 10–15% sequence divergence among these species in the mtDNA ND2 gene, our results suggest that these markers will work broadly across most members of the species rich bird family Nectariniidae.     

Characterization and screening of microsatellite loci in a wild lemur population (Propithecus verreauxi verreauxi).

Sixteen dinucleotide microsatellite loci were isolated from the genome of Propithecus verreauxi verreauxi. All loci were polymorphic when genotyped on a minimum of 16 animals. The number of alleles across these loci ranges from two to 11. Additionally, seven of these loci were genotyped across a minimum of 200 animals in order to estimate heterozygosity and their potential for parentage assignment in this population. Using these seven loci, the mean heterozygosity in this population is 0.705, and the combined probability of these seven loci to exclude a random individual from parentage, when one parent is known, is 0.996. These data suggest that these loci will be useful for estimating a variety of population genetic and genealogical parameters in P. v. verreauxi populations.     

对华南地区男性成年颅骨、锁骨、肩胛骨和髋骨与身高关系的研究

作者对近年在华南地区收集的70具成年男性完整骸骨的颅围、锁骨最大长、肩胛骨形态宽及髋骨最大长进行了测量。相关分析表明,各测量项目与身高的相关系数均有非常显著的意义(p<0.01)。进而建立了相应的回归方程。用70例已知生前身高的国人骸骨对这些回归方程进行了检验。结果表明,本文所建立的这些回归方程均有一定的实用价值。     

紫扇贝与海湾扇贝通用SSR的检测及其在杂交子代鉴定中的应用

以紫扇贝DNA为模板,用已开发的147个海湾扇贝微卫星标记引物扩增,结果表明100个微卫星标记能成功扩增,其中有47个表现出多态性,等位基因数目从2到9不等.观测杂合度范围为0.128 0～1.000 0(平均0.660 4),期望杂合度范围为0.503 1～0.862 1(平均0.671 9),有6个位点偏离Hardy-Weinberg平衡(P<0.05).用7对引物分别对紫扇贝、海湾扇贝及其种间正反杂交F1各30个个体进行PCR扩增,发现它们可明确区分紫扇贝与海湾扇贝,且所检测60个杂交子代均同时含海湾扇贝与紫扇贝的相应种特异性条带,证明全部为种间杂交子代.将该7对引物的扩增产物克隆测序,发现这些位点在两种扇贝中的序列同源率为40.22%～91.95%,其中3个位点在紫扇贝中的扩增产物仍然含有微卫星.     

Comparative studies on cell lines established from normal and radiation-exposed miniature swine.

Cloned cell lines were established from two swine with radiation-induced myeloproliferative disorders, including one cell culture from an animal with myelogenous leukemia and one from an animal with myeloid metaplasia. A third cloned cell line with similar morphology was established from pooled normal fetal swine cornea to compare the growth characteristics of cells from normal and irradiated swine. All three cell lines grew as foci of aggregated cells and were able to form macroscopic colonies in semisolid agar medium. The lack of normal mechanisms of contact inhibition and the observed aneuploidy indicated that these cells were morphologically transformed. Further, the cloned cells caused tumors in nude mice, clearly indicating that these cells were also malignantly transformed. A major difference between these cell lines was that type C viruses were observed only in the cells derived from swine with myeloproliferative disorders.     

Prolonged Salmonella Contamination of a Recreational Lake by Runoff Waters

In the summer and fall of 1968, various Salmonella serotypes were isolated from a portion of Lake Mendota, the major recreational lake for Madison Wis. The apparent sources of these organisms were a residential storm sewer and a University of Wisconsin Experimental Farms' washwater drain. Salmonellae were isolated with regularity from a swimming beach located approximately 0.5 mile (0.8 km) from these sources.     

Staphylococcus aureus and Micrococcus luteus peptidoglycan transglycosylases that are not penicillin-binding proteins.

Major peptidoglycan transglycosylase activities, which synthesize uncross-linked peptidoglycan from lipid-linked precursors, were solubilized from the membranes of Staphylococcus aureus and Micrococcus luteus and were partially purified. The transglycosylase activities were separated from penicillin-binding proteins by solubilization and by purification steps. Therefore, we concluded that these activities were not activities of the penicillin-binding proteins, which are the presumptive peptidoglycan transpeptidases in these gram-positive cocci. Unlike Escherichia coli, in which the network structure of peptidoglycan is synthesized by multiple two-headed penicillin-binding proteins with both transpeptidase and transglycosylase activities, these gram-positive cocci have cell wall peptidoglycan which seems to be synthesized by penicillin-binding protein transpeptidases and a separate transglycosylase.     

Protein alterations in isolated outer membranes of polymyxin-resistantPseudomonas aeruginosa isolates

Isolated outer membranes fromPseudomonas aeruginosa strains resistant to polymyxin were compared with isolated outer membranes from polymyxin-sensitive strains as to their protein composition as determined by slab polyacrylamide gel electrophoresis. Both the porin protein and the H1 protein were decreased greatly in concentration in the outer membranes from the polymyxin-resistant strains. This confirms previous findings reduced concentrations of these proteins in cell envelopes of these strains. No evidence was found for these decreases being the result of an artifactual loss of these proteins from the outer membrane due to conditions used for growth or for preparation of cell envelopes. Nevertheless, the role of these outer membrane proteins in mediating polymyxin resistance is uncertain.     

The cytolytic T lymphocyte response to trinitrophenyl-modified syngeneic cells. I. Evidence for antigen-specific helper T cells.

Mice were primed subcutaneously with trinitrophenyl (TNP)-modified syngeneic spleen cells. Seven days later, spleen cells from these in vivo primed mice, or spleen cells from naive mice, were co-cultured with TNP-modified syngeneic cells. Spleen cells from the in vivo primed mice demonstrated augmented cytolytic T lymphocyte (CTL) activity. The spleens of these in vivo primed mice contained a population of radioresistant, antigen-specific, helper T cells. Specifically, spleen cells from these mice, after x-irradiation, were able to augment the in vitro CTL response of normal spleen cells to TNP-modified syngeneic cells.