Evaluation of purified H and M antigens of histoplasmin as reagents in the complement fixation test.

Complement-fixation (CF) tests were performed with purified H and M antigens, histoplasmin, and Histoplasma capsulatum whole cell yeast phase antigen using sera of 126 patients with proven or suspected histoplasmosis. Specific titers for either H or for M antibody were obtained with the individual purified antigens; the highest titers were comparable to those obtained with histoplasmin. However, in sera containing only anti-M antibody, the titers obtained with the purified M antigen were 2 to 16 times those obtained with the histoplasmin or yeast phase antigens. The CF test for either H or M antibody was 4 to 32 times as reactive as the agar-gel microimmunodiffusion test; in general precipitin lines were obtained with either H or M antigens from sera with CF titers greater than or equal to 8. With sera containing H antibody, there was an excellent correlation between the CF titers obtained with purified M antigen and histoplasmin. The correlations of CF titers with H antigen and either histoplasmin or yeast phase antigen were very low.     

Inhibition of sperm transport and fertilization in superovulating ewes

In Experiment 1, all ewes were treated with follicle stimulating hormone (FSH-P) to induce superovulation. Ewes came into natural estrus or were treated with prostaglandin F(2)alpha (PGF(2)alpha) or 6-methyl-17-acetoxyprogesterone (MAP) to regulate the time of estrus. The ewes were mated during estrus and necropsied 3 h after mating. Regulation of estrus with either compound reduced the number of sperm recovered from the cervix, uterus, and oviducts and increased the proportions of sperm recovered from the cervix and uterine body that were immotile, dead, or had disrupted membranes. In Experiment 2, all ewes were in natural estrus. They either ovulated naturally or were superovulated, and ewes in each group were necropsied at 3 or 23 h after mating. Superovulation reduced the number of sperm in oviducts, uterus, and anterior segments of the cervix at both time intervals and increased the proportions of sperm that were immotile, dead, or had disrupted membranes. In Experiment 3, of 3x2 design, ewes were in either natural estrus or estrus regulated with PGF(2)alpha or with MAP; they ovulated naturally or were superovulated. Ewes were necropsied 3 d after mating and ova were examined. Both regulation of estrus and superovulation reduced the proportion of ova that were fertilized and reduced the number of accessory sperm attached to fertilized ova.     

The Results of Parenteral Injections of Sporulated or Unsporulated Oocysts of Eimeria bovis in Calves

SYNOPSIS. Five experiments using newborn Holstein-Friesian and weaner Hereford calves were conducted to observe the effects caused by parenteral injections of oocysts of Eimeria bovis . Sporulated oocysts were given intraperitoneally (IP), subcutaneously (SC), intramuscularly (IM) and intravenously (IV). Unsporulated oocysts or merozoites were given IP or IM.
Coccidiosis developed in calves in three experiments after they were inoculated IP with sporulated oocysts. Immunity to reinfection resulted from these infections. No infections occurred at any time after SC, IM or IV inoculation with sporulated oocysts or after IP or IM inoculation with unsporulated oocysts or merozoites.
Coccidiosis failed to occur in two experiments when special precautions were used to prevent puncture of the intestines during IP inoculations. There was no detectable immunological response to any of the inoculations unless intestinal infections occurred.
In one experiment sporulated oocysts were exposed to 60,000 r irradiation by x-ray in an attempt to attenuate the oocysts. Calves became infected when given orally administered oocysts irradiated at this level.     

Bolting Susceptibility of Sugar Beet (Beta vulgaris) in Relation to Contents of Sulfhydryls and Disulfides and to Protein Composition of Membranes

The aim of the investigation was to correlate the sensitivity to low temperature that leads to bolting of sugar beet with a property of seedlings or seeds, analyzable without cold treatment. Populations or inbred lines were investigated, the bolting percentages of which had been determined in field trials. Sulfhydryls (—SH) and disulfide sulphur (-S-) were analyzed by amperometric titration with silver nitrate. Disulfides were broken with sulphite, and proteins were unfolded with urea. Negative correlations were found between the bolting percentage and (-SH + -S-) per leaf fresh or dry weight unit and per leaf protein nitrogen, with urea at the titrations. Positive correlations were obtained between the bolting percentage and the ratio of (-SH + -S-) titratable in the absence of urea to that titratable in the presence of urea, when leaf homogenates or leaf or seed protein precipitates were examined. Centrifugation experiments showed that membrane proteins were responsible for the correlation. By polyacrylamide gel electrophoresis of the membrane proteins it was found that the proportion between some of these proteins was correlated with the bolting percentage. From these results and such from analyses of beet plants during and after cold treatment a hypothesis was constructed: Low bolting susceptibility, i.e., low sensitivity to low temperature, is caused by a high proportion of a hydrophobic membrane protein, rich in -SH or -S-. This protein interferes with the reactivity of the plants to gibberellins resulting from low temperatures or long days.     

Capping of immune complexes by sporozoites of Eimeria tenella

Sporozoites of Eimeria tenella were incubated for 10, 20, or 30 min with parasite-specific monoclonal IgG antibody 3D3II from mice and then rinsed in a Tris-buffered glucose saline solution (TBGS). Some sporozoites were then incubated for 10, 20, or 30 min with ferritin- or colloidal gold-conjugated goat anti-mouse IgG antibody and then fixed in 2.5% glutaraldehyde and prepared for transmission (TEM) or scanning (SEM) electron microscopy. Other sporozoites that had been previously exposed to monoclonal antibody were prefixed with 0.25% glutaraldehyde, incubated with ferritin- or colloidal gold-conjugated anti-mouse IgG antibody and then fixed and prepared for TEM or SEM. Control preparations consisted of sporozoites exposed only to TBGS, monoclonal antibody 3D3II or to ferritin- or colloidal gold-conjugated anti-mouse IgG antibody. Capping of immune complexes occurred only on the surface of those sporozoites exposed to monoclonal antibody 3D3II followed by ferritin- or gold-conjugated antibody. Immune complexes moved laterally and posteriorly on the outer surface of the parasite plasma membrane to form a cap at the posterior end of the sporozoite. Capping did not occur in TBGS controls nor in sporozoites treated with monoclonal antibody 3D3II and prefixed in 0.25% glutaraldehyde before exposure to ferritin- or gold-conjugated antibody. Thus, capping of surface antigens did not occur in the presence of monoclonal 3D3II antibody only, whereas specimens exposed to both monoclonal and ferritin- or colloidal gold-conjugated antibodies were able to cap immune complexes.     

Effect of the stage of pregnancy and post-partum on the number of gonadotrophin responsive follicles in ewes

The present study was designed to study follicular growth and its interactions with the corpus luteum of pregnancy in sheep during early, middle and late pregnancy and during postpartum anestrus. Ewes with 1 or 2 corpora lutea in one ovary were selected from a larger group of Serres ewes. All pregnant ewes were randomly allocated to two groups, with 10 to 12 ewes per group. Ewes of Group I were treated with 750 IU hCG at Day 25 or 45 or 70 or 100 or 125 of pregnancy. In Group II, ewes were treated with a combination of 1000 IU PMSG + 750 IU hCG either at Day 25 or 45 or 70 or 100 of pregnancy. The results demonstrated the presence of gonadotrophin-responsive follicles during early pregnancy (Days 25 to 45), reduction of their number during mid-pregnancy (Days 70 to 100), and their disappearance during late pregnancy (Day 125). Administration of hCG to Serres ewes at 10 and 20 days postpartum induced ovulation of a high proportion of ewes at 10 days postpartum (62%) with a further increase observed at 20 days postpartum (75%). During pregnancy, as well as during the postpartum period, there was no significant difference in the number of ovulations induced according to the location of the corpus luteum of pregnancy. These data demonstrate that the presence of the corpus luteum of pregnancy does not affect the number of gonadotrophin-responsive follicles until Day 100 of pregnancy. However, during late pregnancy such follicles were no longer present in the ovaries. Gonadotrophin-responsive follicles were again present as soon as Day 10 postpartum.     

Effects of volume, culture media and type of culture dish on in vitro development of hamster 1-cell embryos

We examined effects of medium volume and two different culture media (HECM-3 and HECM-4) on in vitro development of hamster embryos. Groups of 5 to 8 1-cell embryos were cultured for 72 h in either < or =100 or > or =100 microl volumes. In the first experiment, embryos were cultured in Petri dishes with 2, 5, 20, 50 or 100 microl of medium using the two media (2 x 5 factorial experiment). Optimal volumes for morula and blastocyst development were 100 microl of HECM-3 and > or =50 microl of HECM-4; in HECM-4, > or =20 microl volumes were suitable whereas in HECM-3 < or = 50 microl volumes were unsuitable. In the second experiment, embryos were cultured in 100, 200, 500 and 1000 microl of HECM-3 and HECM-4 using organ culture dishes. Controls were 100 microl drops in Petri dishes. In organ culture dishes, blastocyst development was < or =6% in HECM-3 and 33-41% in HECM-4, and suitable volumes for development to at least morulae were > or =200 microl of HECM-3, and > or =100 microl of HECM-4. In both experiments development to morula and blastocyst stages with 100 microl volume in Petri dishes was significantly higher with HECM-4 (96 and 85% in Experiment 1 and 2, respectively) than that with HECM-3 (52 and 40% in Experiment 1 and 2, respectively; P < 0.05). These results indicate that attention should be paid to both type and volume of medium and interaction with type of culture dish for optimizing development of embryos in vitro.     

A dendrogram of plant viruses.

To facilitate the recognition of plant viruses with similar characteristics a dendrogram of characterized viruses was constructed. The sequence of criteria included: type of nucleic acid; single or double stranded; presence or absence of lipid envelope; helical or nonhelical symmetry; and divided or single genome. Nonhelical RNA viruses with divided genomes were further divided into viruses with one or more than one capsid size. Those with one capsid size were subdivided into viruses with one or more than one sedimenting component. Nonhelical RNA viruses with a single genome were divided according to their RNA size, and their sensitivity to sodium dodecyl sulfate and ethylenediaminetetraacetic acid.     

Effect of serum,fibronectin, and laminin on adhesion of rabbit intestinal epithelial cells in culture

Rabbit intestinal epithelial cells, obtained after a limited hyaluronidase digestion, were incubated in medium with or without calf serum, on bacteriological plastic dishes. The dishes, either plain or coated with an air-dried type I collagen film, were pretreated with medium alone or with medium containing purified laminin or purified fibronectin. Cells did not attach in significant numbers to untreated bacteriological plastic, even in the presence of serum. Cells did attach to collagen-coated dishes, and were judged viable on the basis of their incorporation of radiolabeled leucine into cell protein. Cell adhesion to the collagen substrate increased in proportion to the concentration of serum in the medium, with maximal attachment at 5% serum or greater. Pretreatment of plain or collagen-coated dishes with increasing amounts of fibronectin enhanced cell adhesion in a concentration-dependent manner. Either serum, or fibronectin-free serum in the medium enhanced cell attachment to substrates pretreated with cither fibronectin or laminin. Thus, intestinal epithelial cells appear to possess surface receptors for both laminin and fibronectin. The evidence further suggests that calf serum may contain factors, other than fibronectin, capable of enhancing intestinal epithelial cell attachment to collagen substrates.     

Developmental defects of female-sterile mutants of Drosophila melanogaster

Gans et al. (1975) isolated female-sterile mutants, viable and normal in the homozygous state, producing apparently normal eggs which were unable to develop or developed into defective embryos or adults, even when fertilized with wild-type sperm. Developmental abnormalities of these mutants were surveyed by observing living and fixed material. The following types of mutants were distinguished according to the predominant developmental defect: (i) Eggs not developing at all, mostly remaining unfertilized. (ii) Eggs stopping development after a few cleavages, some with polyploid nuclei. (iii) Eggs stopping development at various embryonic stages, with haploid nuclei. (iv) Eggs with abnormal blastoderm, not developing further or giving abnormal embryos. (v) Eggs with abnormal gastrula, in one case with excessive invaginations, in another case with germ band failing to elongate. (vi) Eggs with embryos dying at different stages, without easily visible effects. Several of the mutants were temperature sensitive. In all the mutants there were eggs that died without developing. Most of the developmental defects appear to be due to general metabolic disturbances of the egg, not directly related to morphogenesis. There were no mutants affecting determination of a particular adult organ. The closest to a morphological type of mutation were those with abnormal blastoderm having successive bands of nuclei of different sizes. Those mutants were thermosensitive; at permissive termperatures they developed into agametic adults or adults with various defects of abdomens, wings or eyes. The nature of maternal genetic control of early morphogensis was discussed.     

Serologic diagnosis of syphilis; the use of Treponema pallidum immobilization and immune adherence tests

TPI tests were carried out on 4,060 sera. Among 3,934 patients with reactive STS and no history of syphilis, 2,148 or 54.6 per cent had negative reaction to TPI tests, 1,695 or 43.1 per cent had positive reaction and 91 or 2.3 per cent had doubtful reaction. Two hundred and ninety-two or 73.0 per cent of 400 pregnant women with reaction to STS in the absence of a history of syphilis showed negative results by TPI test, 103 or 25.8 per cent had positive results and five or 1.2 per cent had doubtful reaction.Ninety-five or 75.4 per cent of 126 patients with a history of treated syphilis had positive reaction to TPI tests, 20 or 20.2 per cent had negative reaction and nine or 9.1 per cent had doubtful reaction.TPI and TPIA tests were done on 143 sera carefully selected for the study. Among 102 sera subjected to the TPI test, 46 or 100 per cent of these positive were also positive by TPIA tests, while 52 or 94.5 per cent of 55 TPI-negative sera were also nonreactive by TPIA test. One serum gave doubtful TPI test reaction and positive TPIA test reaction.     

Effect of a serum extender containing growth factors on development of IVM and IVF bovine embryos

The present experiments were conducted to determine if supplementation of the culture medium with a serum extender containing growth factors would increase development of bovine embryos into morulae or blastocysts, following in vitro maturation (IVM) and in vitro fertilization (IVF). In Experiment 1, bovine zygotes were cultured in CR1 medium supplemented with 0, 0.01, 0.1, 1 or 10% serum extender. In Experiment 2, bovine zygotes were cultured in the presence of cumulus cells in CR1 medium supplemented with 0, 0.01, 0.1, 1 or 10% serum extender. In Experiment 3, bovine oocytes were matured in Medium 199 supplemented with 0, 0.01, 0.1, 1 or 10% serum extender. In Experiment 4, oocytes were matured in Medium 199 with 10% fetal bovine serum (FBS) or 5% FBS with serum extender. Following maturation, zygotes were cultured in CR1 medium with 10% FBS or 5 % FBS and serum extender. In all 4 experiments, the embryos were cultured in vitro until Day 7 after IVF, and development to the morula or blastocyst stage was assessed. The findings of the first 2 experiments showed that the serum extender did not directly influence embryo development but did stimulate development when cumulus cells were included in the culture system. The remaining 2 experiments showed that the serum extender did influence development through its interactions with cumulus cells during maturation and/or culture. These findings suggest that although growth factors or other products do not directly stimulate bovine embryo development their effects may be mediated through secondary cell systems.     

Synthesis of ethriolophospholipids of acetal type

New analogues of acetal-type phospholipids were obtained on the basis of ethriol (2-hydroxymethy1-2-ethyl-1,3-propanediol). The starting triol originally was condensed with decanal or dodecanal to form acetals, which were then phosphorylated with tetraethyldiamidophosphorous acid chloride. The amidophosphites were further oxidized with iodosobenzene or sulfurized to the corresponding acetal-type phospholipids and their thio analogues.     

中国蔷薇属植物叶表皮微形态特征及其系统学意义

应用光学显微镜和电子显微镜,对30种中国蔷薇属植物叶表皮的微形态特征进行了观察。结果表明:叶表皮细胞一般为多边形或不规则形,垂周壁平直、平直弓状、波状、浅波状和深波状式样;该属植物的叶表皮细胞大小种间差异较大,总体来看上表皮几乎全为多边形细胞,且上表皮细胞比下表皮细胞略大;在扫描电镜下观察,大部分细胞的平周壁下陷,仅部分细胞的平周壁突起;叶表皮角质层纹饰多样、即使同一个种的上下表皮细胞角质层纹饰微形态特征也有差异;大多植物叶片表面具柔毛,均为单毛,有长柔毛和短柔毛,大部分种类的柔毛基部无特化,其基部由普通的表皮细胞围绕着,少部分种类的柔毛基部由几个特化的辐射状细胞围绕着,少数植物无毛;有些植物叶表面或叶脉上还分布有腺毛;除了单叶蔷薇亚属的小蘗叶蔷薇1个种的上下表皮均分布有气孔器外,其余蔷薇亚属的29种植物的气孔器均分布在下表皮,形状为椭圆形、宽椭圆形和长椭圆形三种,气孔器类型有无规则型、不规则四细胞型、对位四细胞型、环列型和辐射型;气孔器外拱盖内缘近平滑或呈深浅不同的波状、气孔器外拱盖纹饰光滑或粗糙,大多植物气孔器的保卫细胞两级T型加厚;另外,只有小蘗叶蔷薇的气孔器具双层外拱盖且仅上表皮被毛等特征也说明了其在演化上的特殊地位,蔷薇属植物叶表皮的这些微形态特征,在属内各组间无明确的规律性,但可为探讨该属种间的分类学及亲缘关系提供依据。     

Effects of carbohydrates and lectins on cryptosporidial sporozoite penetration of cultured cell monolayers.

Cryptosporidium parvum first interacts with enterocytes when sporozoites penetrate the host plasma membrane. We have developed a shell vial assay using human embryonic Intestine 407 cells and purified C. parvum sporozoites to study this process. Sporozoites were incubated in culture medium with various carbohydrates and lectins, and the suspensions were then added to the cell monolayers. Following incubation, the monolayers were fixed and stained and the number of schizonts were counted. No decreases in sporozoite motility or Intestine 407 cell viability were observed with carbohydrate or lectin treatment. N-Acetyl-D-glucosamine, chitobiose and chitotriose inhibited C. parvum infection, compared to 5 other tested carbohydrates. Wheat germ agglutinin reduced penetration and concanavalin A enhanced schizont formation, when compared to 8 other lectins. Next, we pretreated sporozoites or Intestine 407 cells with wheat germ agglutinin and concanaval in A prior to sporozoite inoculation. Wheat germ agglutinin treatment of sporozoites or cells equally caused a reduction in C. parvum infection, while enhancement was only observed when Intestine 407 cell were pretreated with concanavalin A. These data suggest that glycoproteins with terminal N-acetyl-D-glucosamine residues may play a role in C. parvum adhesion or penetration of enterocytes. Also, host glycoproteins with concanavalin A-like activity may play a role in these processes.     

Lack of Fc receptors on osteoclasts

Summary Fc and C₃ receptors, which are characteristically present on macrophages, could not be demonstrated on osteoclasts maintained in situ on their normal substrates when assayed for by use of sheep red blood cells coated with immmoglobulin (Shapiro et al. 1979). The present study tested the hypotheses that Fc receptors are present only on the osteoclast surface adjacent to bone and that Fc receptors on osteoclasts can be uncovered by enzymes or stimulated to appear. Freeze-dried, inverted osteoclasts (and osteoblasts) obtained from the endocranium of newborn rats were tested for Fc receptors using the rosette assay and examined by scanning electron microscopy. No rosettes were observed on the surfaces of the osteoclasts that had been approximal to the bone. Bone specimens were cultured for 30 min at 37° C in control medium, or in medium with the addition of 10, 50 or 100 gmg/ml trypsin, 0.5 U/ml parathyroid extract (PTE), or 0.5 or 1U/ml parathyroid hormone 1–34 (PTH). Additionally, two week-old rats were injected intraperitoneally with PTE (1.5 U/g body weight or 1USP/g body weight) or with PTH (1U/g body weight) or with vehicle alone, 6 h before sacrifice. The specimens were assayed for Fc receptors and examined by scanning electron microscopy. Macrophages were always used as controls for the assay. No rosettes were present on osteoclasts subjected to any of these treatments. Accordingly, the hypotheses were not supported.     

The effect of cyanobacteria and azolla on the performance of rice under different levels of fertilizer nitrogen

Cyanobacteria and/or azolla were inoculated, with urea at 0, 72 or 144 kg N/ha, in plots in which azolla-free Indica rice var. IR 28 was grown. Productive tillers, yield and nitrogen contents of grain and straw positively responded to inoculation with cyanobacteria or azolla, even with fertilizer-N up to 144 kg N/ha. Inoculation improved colonization by cyanobacteria. Azolla were superior to the asymbiotic cyanobacteria in enhancing rice performance. Urea at a rate of 72 kg N/ha was found to support the best colonizations when applied with cyanobacteria or azolla or, to give maximum rice yields, both inoculants.     

The effect of thiols on immunologic release of slow reacting substance of anaphylaxis. I. Human lung.

Preincubation of human lung fragments with cysteine for 2.5 to 5.0 min resulted in dose-dependent, selective enhancement of the antigen-induced or anti-IgE-induced formation and release of slow reacting substance of anaphylaxis (SRS-A). Comparable effects were observed with sodium sulfide and thioglycolate but not with other more potent reducing agents or metabolites of cysteine. Sulfhydryl alkylated derivatives of cysteine were ineffective. The effects observed with the active thiols were easily reversed and could not be attributed to an action in the bioassay or on SRS-A itself. The physicochemical characteristics of the contractile activity were identical to those described for SRS-A.     

Morphology of the canine pyloric sphincter in relation to function

The ultrastructure and immunocytochemistry of the canine distal pyloric muscle loop, the pyloric sphincter, were studied. Cells in this muscle were connected by gap junctions, fewer than in the antrum or corpus. The sphincter had a dense innervation and a sparse population of interstitial cells of Cajal. Most such cells were of the circular muscle type but a few were of the type in the myenteric plexus. Nerves were sometimes associated with interstitial cell profiles, but most nerves were neither close to nor associated with interstitial cells nor close to smooth muscle cells. Nerve profiles were characterized by an unusually high proportion of varicosities with a majority or a high proportion of large granular vesicles. Many of these were shown to contain material immunoreactive for vasoactive intestinal polypeptide (VIP) and some had substance P (SP) immunoreactive material. All were presumed to be peptidergic. VIP was present in a higher concentration in this muscle than in adjacent antral or duodenal circular muscle. Interstitial cells of Cajal made gap junctions to smooth muscle and to one another and might provide myogenic pacemaking activity for this muscle, but there was no evidence of a close or special relationship between nerves with VIP or SP and these cells. The absence of close relationships between nerves and either interstitial cells or smooth muscle cells leaves unanswered questions about the structural basis for previous observations of discrete excitatory responses or pyloric sphincter to single stimuli or nerves up to one per second. In conclusion, the structural observations suggest that this muscle has special neural and myogenic control systems and that interstitial cells may function to control myogenic activity of this muscle but not to mediate neural signals.     

Infection of SDAV-immune rats with SDAV and rat coronavirus

Infection of rats with sialodacryoadenitis virus (SDAV) or rat coronavirus (RCV) is acute and self-limiting, and elimination and control of either virus is based on the assumption that recovered rats are immune to reinfection. To test this hypothesis, we examined whether SDAV-immune rats could be infected with RCV or reinfected with SDAV. Sprague Dawley (SD) rats were inoculated intranasally with SDAV or with culture medium alone and serial SDAV antibody titers were obtained. Eleven months after inoculation, when antibody titers had stabilized, SDAV-immune and nonimmune rats were challenged with SDAV or RCV, and euthanatized 3 or 6 days later. SDAV-immune rats challenged with SDAV or RCV manifested acute rhinitis associated with virus antigen by 3 days after inoculation, but no lesions or antigen were subsequently found in the lower respiratory tract, salivary glands or lacrimal glands. There was also a marked anamnestic increase in antibody titer by 6 days after challenge. SDAV-immune rats challenged with SDAV or RCV also transmitted infection to nonimmune cage mates. This study indicates that 11 months after primary infection with SDAV, rats can be infected with SDAV or RCV, but that the severity of disease is significantly reduced.