Purification, and biochemical and structural characterization of a fimbrial haemagglutinin of Renibacterium salmoninarum

Renibacterium salmoninarum was shown to possess peritrichous fimbriae. Electron microscopy of strains FMV 84-01 and ATCC 33209T revealed short, flexible fimbriae less than 2 nm in diameter. These surface appendages were isolated from the bacteria by a procedure involving water extraction and urea solubilization. The fimbrin was purified to homogeneity by Fast Pressure Liquid Chromatography, and shown by SDS-PAGE to be a protein of 57 kDa. Isoelectric focusing under non-denaturing conditions indicated a pI of 4.8. The protein had an amino acid composition rich in glycine, Asx (aspartic acid and asparagine), valine and alanine; methionine was absent. Approximately 33% of the amino acid residues were hydrophobic. Immunoblotting using a polyclonal antiserum raised against whole cells showed that the 57 kDa protein was the immunodominant antigen on the cell surface. Immunogold labelling using polyclonal antibodies raised against the fimbrin revealed an alignment of gold particles along the fimbriae. Purified fimbriae caused agglutination of rabbit erythrocytes and antifimbrial serum inhibited this haemagglutination. Altogether the results indicate that the fimbriae on the surface of R. salmoninarum are responsible for the haemagglutinating activity.

Comparing two sampling techniques for endocervical cell recovery on Papanicolaou smears

The importance of endocervical cells in a Pap smear is well-recognized. A Pap smear lacking endocervical cells is considered inadequate and necessitates a repeat test. Clinicians continue to search for techniques that will ensure consistently adequate samples. In this study, Pap smears were obtained for 200 subjects, alternating use of a saline-moistened cotton-tipped applicator with the Zelsmyr Cytobrush for endocervical cell collection. Endocervical cells were present in all 100 Cytobrush smears, compared with 91 of the cotton-tipped applicator smears. The difference is significant (p less than 0.005). The nine smears that lacked endocervical cells were repeated, using the Cytobrush; all nine repeat smears contained endocervical cells. Although the sample used in this study was small, results indicate that the Cytobrush is more effective in obtaining endocervical cells than the cotton-tipped applicator. Use of the Cytobrush is recommended in the interest of reducing the number of false negative reports.

Clinical and microbiological evidence for endemic pharyngitis among adults due to group C streptococci

Group C beta-hemolytic streptococci cause rare epidemic outbreaks of pharyngitis, but their role in sporadic endemic pharyngitis has been uncertain. We addressed the question of whether non-group A beta-hemolytic streptococci are associated with endemic pharyngitis in two ways. First, we compared rates of isolation from throat swabs of group A, B, C, and G and ungrouped beta-hemolytic streptococci ("culture negative") in adult patients vs those rates in controls. Second, we collected in standardized form clinical indexes of patients with pharyngitis: signs and symptoms graded for severity, the examining physician's subjective estimate of the probability of streptococcal pharyngitis, a logistic regression score predicting streptococcal pharyngitis, and whether antibiotic therapy was prescribed. After collecting data and cultures on 1425 patients with sore throats and cultures on 284 controls, we found the following: group C streptococci were isolated significantly more frequently in patients with sore throats than in controls (6% vs 1.4%); four clinical signs and two symptoms distinguished group C-associated pharyngitis as more severe than culture-negative pharyngitis; and six clinical signs and one symptom distinguished group C-associated pharyngitis as less severe than group A pharyngitis. Physicians' subjective estimates, logistic regression scores, and antibiotic treatment all characterized group C-associated pharyngitis as more severe than culture-negative sore throats but less severe than group A pharyngitis. From these data we present the first definitive evidence that group C streptococci are associated with endemic pharyngitis, show that clinical presentation distinguishes a group of patients with group C-associated pharyngitis from populations with culture-negative sore throats and from those with group A pharyngitis. Physicians' response to that presentation merits consideration in the context of rapid group-specific diagnosis of streptococcal pharyngitis by group A antigen tests.

Mutants of Escherichia coli O9:K30 with altered synthesis and expression of the capsular K30 antigen

Escherichia coli K30 produces a thermostable group I capsular polysaccharide. Two classes of mutants were isolated with defects in the synthesis or expression of capsule. The most common mutant phenotype was acapsular (K-), with no K-antigen synthesized. A second class of mutants, termed Ki or intermediate forms, produced colonies which were indistinguishable from those of acapsular forms yet K-antigenicity was expressed. Previous studies had demonstrated that E. coli strains that produce K30 antigen synthesize a lipopolysaccharide (LPS) fraction that is recognised by monoclonal antibodies against the K30 antigen. Synthesis of this LPS fraction was not affected in Ki forms. The results of morphological examination, LPS analysis and phage sensitivity studies are consistent with the interpretation that the defect in Ki strains results from an inability to polymerize the K30 antigen. Using plasmid pULB113 (RP4::mini-Mu), mutations resulting in both K- and Ki phenotypes were localized near the his region of the chromosome.

Simultaneous determination of the reducible and nonreducible cross-links of connective tissue. Analysis of mineralized and nonmineralized bone collagen

Secondary amine cross-links occur in collagen and elastin from a number of tissue sources. Quantification of these cross-links by amino acid analysis is complicated by the problem of separating cross-links, which are often minor components, from the more common amino acids and also because relatively large amounts of a cross-link are required to determine a color factor. A specific radioactive labeling method has been developed and used to quantify cross-links in bone collagen. Primary amines such as lysine and hydroxylysine are first guanidinated with 3,5-dimethylpyrazole-1-carboxamidine nitrate (DMPC). Secondary amines, which are unreactive with DMPC, are then quantitatively cyanoethylated with [14C]acrylonitrile. This procedure can be used to detect any secondary amine cross-link, with higher sensitivity than ninhydrin analysis, in peptide form as well as in acid hydrolysates. It is applied here in conjunction with [3H]NaBH4 reduction to simultaneously quantify Schiff base cross-links and amounts of in vivo reduction of Schiff bases in mineralized versus nonmineralized bovine bone.

Peptidylglycine alpha-amidating monooxygenase activity in spinal cord, dorsal roots, and dorsal root ganglia of Macaca fascicularis

Several peptides synthesized by primary sensory neurons are alpha-amidated at the C-terminal residue, including vasoactive intestinal polypeptide, neurokinin A and substance P, which is also abundant in spinal cord. In pituitary and other tissues, the C-terminal amidation is catalyzed by peptidylglycine alpha-amidating monooxygenase (PAM). In the present study, soluble PAM activity in spinal cord and in primary sensory neurons is quantified and characterized as to cofactor and cosubstrate requirements and substrate specificity.

Molybdate transport by Bradyrhizobium japonicum bacteroids

Bacteroid suspensions of Bradyrhizobium japonicum USDA 136 isolated from soybeans grown in Mo-deficient conditions were able to transport molybdate at a nearly constant rate for up to 1 min. The apparent Km for molybdate was 0.1 microM, and the Vmax was about 5 pmol/min per mg (dry weight) of bacteroid. Supplementation of bacteroid suspensions with oxidizable carbon sources did not markedly increase molybdate uptake rates. Anaerobically isolated bacteroids accumulated twice as much Mo in 1 h as aerobically isolated cells did, but the first 5 min of molybdate uptake was not dependent on the isolation condition with respect to O2. Respiratory inhibitors such as cyanide, azide, and hydroxylamine did not appreciably affect molybdate uptake, even at concentrations that inhibited O2 uptake. The uncouplers carbonyl cyanide m-chlorophenylhydrazone (CCCP) and carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP) and the ionophores nigericin and monensin significantly inhibited molybdate uptake. The electrogenic ionophores valinomycin and gramicidin stimulated molybdate uptake. Rapid pH shift experiments indicated that molybdate transport depends on a transmembrane proton gradient (delta pH), and it is probably transported electroneutrally as H2MoO4. Most of the 99MoO4(2-) taken up was not exchangeable with a 100-fold excess of unlabeled MoO4(2-). Tungstate was a competitive inhibitor of molybdate uptake, with a Ki of 0.034 microM, and vanadate inhibited molybdate uptake slightly.

Mycobacterium avium complex pseudobacteriuria from a hospital water supply

From July 1983 through November 1985, organisms belonging to Mycobacterium avium complex were isolated from the urine of 29 patients. Strains recovered from the urine of nine patients from July 1983 through August 1984 were serotyped. Eight of the nine samples belonged to serovar 4. M. avium complex was isolated from the urine of 21 patients during the period from November 1984 through November 1985. While the possibility of a point source contamination was investigated, M. avium complex was recovered from the phenol red solution used for processing urine specimens in the mycobacteriology laboratory and the deionized tap water of that laboratory that is used to make the reagent. M. avium complex serovar 4 was subsequently recovered from the tap water of the laboratory and four hospital wards. During the year following the installation of a microbiological filter for the mycobacteriology laboratory deionized tap water, 2 urine isolates were recovered, compared to 26 the previous year. This study demonstrates the importance of filtration devices at tap water sites that are used to make laboratory reagents and the value of serotyping as a marker for the detection of a specific source of M. avium complex contamination.

Hydrogen-mediated enhancement of hydrogenase expression in Azotobacter vinelandii

Azotobacter vinelandii cultures express more H2 uptake hydrogenase activity when fixing N2 than when provided with fixed N. Hydrogen, a product of the nitrogenase reaction, is at least partly responsible for this increase. The addition of H2 to NH4+-grown wild-type cultures caused increased whole-cell H2 uptake activity, methylene blue-dependent H2 uptake activity of membranes, and accumulation of hydrogenase protein (large subunit as detected immunologically) in membranes. Both rifampin and chloramphenicol inhibited the H2-mediated enhancement of hydrogenase synthesis. Nif- A. vinelandii mutants with deletions or insertions in the nif genes responded to added H2 by increasing the amount of both whole-cell and membrane-bound hydrogenase activities. Nif- mutant strain CA11 contained fourfold more hydrogenase protein when incubated in N-free medium with H2 than when incubated in the same medium containing Ar. N2-fixing wild-type cultures that produce H2 did not increase hydrogenase protein levels in response to added H2.

Developing a Primary Health Care Task Force

As the number of people with AIDS increases, the number of people impacted by the AIDS crisis will also increase. Larger metropolitan areas have already responded to the crisis with various services (Deuchar, 1984); but the disease has yet to fully impact on smaller cities and towns. The formation of community service groups to cope with the AIDS crisis is a virtual necessity in health care preparation for persons with AIDS. The experience of the Fort Wayne AIDS Task Force reflects the potential of any community to utilize the existing resources in the gay and lesbian community, health and social service professions, and among family and friends of persons with AIDS. Consultation and resources are available through local and state boards of health, as well as local social service and health personnel currently dealing with the AIDS crisis.

Variability in molybdenum uptake activity in Bradyrhizobium japonicum strains

Twenty naturally occurring strains of Bradyrhizobium japonicum in 11 serogroups were screened for the ability to take up Mo as bacteroids from soybean root nodules. The strains varied greatly in their ability to take up Mo in a 1-min period. The best strain was USDA 136, which had an Mo uptake activity of almost 3.0 pmol/min per mg of bacteroid (dry weight). In contrast, the poorest strain, USDA 62, had an Mo uptake activity of 0.35 pmol of Mo per min per mg of bacteroid. There were similarities in Mo uptake ability among most of the same serogroup members. The variability in Mo uptake rates between the best (USDA 136 and USDA 122) and poorest (USDA 62 and USDA 140) strains was attributed to their differing affinities for Mo. Double-reciprocal plots of velocity versus substrate indicated a Km for USDA 136 and USDA 122 of 0.045 and 0.054 microM, respectively, whereas strains USDA 62 and USDA 140 both exhibited an apparent Km for MoO42- of about 0.36 microM. The two strains with the higher-affinity Mo binding also accumulated four to five times as much Mo over a 30-min period as the other strains. Soybeans were grown in Mo-deficient and Mo-supplemented conditions after inoculation with the three top-ranking Mo uptake strains and the three poorest Mo uptake strains. Two separate greenhouse studies indicated that Mo supplementation significantly increased the N2 fixation activity of USDA 140 nodules; up to a 35% increase in specific nitrogen fixation activity of nodules due to Mo supplementation was observed. Strain USDA 62 nodule N2 fixation responded positively to Mo supplementation in one of the two experiments. The results indicate that MoO42- transport and, specifically, affinity for Mo by the bacteroid may ultimately affect symbiotic N2 fixation activity. Attempts to reactivate nitrogenase by adding molybdate to bacteroids from plants grown in Mo-deficient conditions were unsuccessful.

Bradyrhizobium japonicum mutants defective in nitrogen fixation and molybdenum metabolism

Bradyrhizobium japonicum JH mutants deficient in molybdenum metabolism into the enzymes nitrogenase and nitrate reductase were isolated by using the vector pSUP1011, which carries transposon Tn5 (streptomycin and kanamycin resistance). Mutants in Mo metabolism were obtained at a frequency of 3.6 X 10(-3) (per Kan Strr colony). The mutants were detected by their poor ability to grow in nitrate-containing medium without added Mo. One of the mutant types required 10(5) times more molybdate than the wild type to obtain maximal nitrogen fixation activity. Double-reciprocal plots of Mo uptake versus concentration indicated that the wild-type strain had a high- and a lower-affinity component for Mo binding. Mutant strains JH-90 and JH-119 lacked the high-affinity Mo uptake component and were also clearly deficient in Mo accumulation into a nonexchangeable form. Nitrogenase activity as well as Mo uptake ability could be restored in strains JH-90 and JH-119 by the addition of the sterile supernatant fraction of the wild type. Therefore, mutant strains JH-90 and JH-119 appeared to be deficient in an extracellular Mo-binding factor produced by the wild type. Mutant strains JH-14 and JH-143 had Mo uptake kinetics like those of the wild type (both high- and low-affinity binding for Mo) and appeared to be deficient in intracellular Mo metabolism processes. The addition of the wild-type supernatant did not restore Mo uptake or nitrogenase activity in these strains.

Differential medium for mixed cultures of alpha-hemolytic streptococci from blood

Alpha-hemolytic streptococci (AHS) were isolated from blood cultures from 100 patients, and species were identified by the Ruoff and Kunz scheme. When isolates were inoculated onto sheep blood agar, all 100 cultures appeared to be pure, with identifications based on colonial morphology and Gram stain. When isolates were subcultured onto mitis salivarius agar (MSA), mixtures of two species of AHS were detected in 10 cultures from patients (10%). These mixed cultures would have been reported as pure cultures of Streptococcus milleri (six cultures), Streptococcus salivarius (three cultures), Streptococcus sanguis I (one culture), with identifications based on biochemical profiles. Cultures on MSA demonstrated S. milleri (six cultures), Streptococcus mitis (five cultures), S. salivarius (three cultures), S. sanguis I (one culture), and S. sanguis II (five cultures). The inability to separate AHS species by colony morphology on sheep blood agar demands that a differential medium such as MSA be routinely used for subculture. Failure to use such a medium may account for some of the confusing biochemical profiles associated with AHS species identification.

Enrichment for Hydrogen-Oxidizing Acinetobacter spp. in the Rhizosphere of Hydrogen-Evolving Soybean Root Nodules

Field soybean plants were inoculated with Hup + wild-type or H 2 uptake-negative (Hup − ) mutants of Bradyrhizobium japonicum . For two consecutive summers we found an enrichment for acinetobacters associated with the surfaces of the H 2 -evolving nodules. Soybean root nodules that evolved H 2 had up to 12 times more Acinetobacter spp. bacteria associated with their surfaces than did nodules incapable of evolving H 2 . All of the newly isolated strains identified as Acinetobacter obtained from the surfaces of root nodules, as well as known established Acinetobacter strains, were capable of oxidizing H 2 , a property not previously described for this alkane-degrading soil bacterium.

Effect of medium and cultivation conditions on comparisons between latex agglutination and culture detection of group A streptococci

In the laboratory diagnosis of pharyngitis, results from latex agglutination tests (LAT) performed directly on throat swabs are often compared with the isolation of group A beta-hemolytic streptococci (GABHS) from simultaneously obtained swabs cultivated on a variety of media under different atmospheric conditions. In this study, results of an LAT, Directigen, were compared with those of two different media: sheep blood agar (SBA) and group A selective strep agar (ssA). Specimens inoculated on SBA were incubated in three different atmospheres: air, 3 to 5% CO2, and anaerobically. Those inoculated on ssA were incubated in 3 to 5% CO2 only. Isolation of GABHS was confirmed by coagglutination. The standard for true positivity was the isolation of GABHS from at least one of the simultaneous cultures. Comparisons were made with samples from 693 adult patients. GABHS was isolated on at least one of the three cultures in 143 patients, demonstrating an isolation rate of 20.6%. LAT exhibited a sensitivity of 95.1%. SBA incubated in air, in CO2, or anaerobically had sensitivities of 86.2, 85.9, and 93.7%, respectively. The ssA detected 99.3% of the positive specimens. Single SBA culture proved to be inferior to LAT and therefore was a poor standard for measuring LAT performance. Single ssA cultures demonstrated the greatest sensitivity in GABHS detection and therefore could serve as a standard for measuring LAT performance.

[14C]acrylonitrile: preparation via a stable tosylate intermediate and quantitative reaction with amine residues in collagen

A simple, convenient synthetic procedure for [14C]acrylonitrile is described. Na14CN is used as the radioactive starting material. Small (milligram) amounts are converted to 3-[14C]Hydroxypropionitrile by a substitution reaction with 2-chloroethanol. 3-[14C]Hydroxypropionitrile is then tosylated, and the specific activity of this intermediate product is easily determined using its uv extinction coefficient and scintillation counting. [14C]Acrylonitrile is obtained rapidly on distillation by heating the tosylate in the presence of a high boiling tertiary amine base catalyst. The tosylate intermediate can be stored, in contrast to radioactive acrylonitrile, which is unstable. The reaction of acrylonitrile with lysine, hydroxylysine, and histidine residues in human Achilles tendon collagen, as well as chromatographic separation and identification of the carboxyethyl derivatives of these amino acids, is also described.

Rhesus Du incompatibility in a newborn with high levels of anti D and a benign clinical course

The Rhesus variant Du is regarded as a weak form of the Rhesus D antigen, but haemolytic disease of the newborn may occur if the maternal serum contains Anti-D [5]. We describe the case of an infant with Rhesus Du incompatibility and high levels of Anti-D in the maternal serum, but without clinical evidence of haemolytic disease of the newborn.

Gastric outlet obstruction secondary to a distal duodenal stenosis

A case is presented where gastric outlet obstruction was found to be secondary to carcinoma of the distal duodenum in a patient with acute on chronic duodenal ulceration. The fallibility of barium studies in this condition is discussed.

Diffusion of labeled water and lipophilic solutes in the lung

A perfused, in situ rabbit lung preparation was used to study the diffusion of tritiated water and labeled lipophilic solutes from the airways into the pulmonary vasculature. Following instillation into the airways, initial concentrations of labeled ethanol and butanol in the left atrial outflow usually exceeded those of 3H2O when the lungs were perfused at 37 degrees. In contrast, initial concentrations of [14C]acetone equaled 3H2O concentrations, and those of [14C]antipyrine were below 3H2O concentrations. Increasing the rate of perfusion increased concentrations of the labeled butanol and acetone but decreased that of antipyrine relative to 3H2O. This suggests that the tissues separating the gaseous and vascular compartments of the lung are more permeable to 3H2O than to antipyrine but less permeable to 3H2O than to the alcohols and acetone. Cooling slowed permeation of ethanol and antipyrine relative to 3H2O but seemed to slow diffusion of butanol less than that of 3H2O. These differences cannot be related to movement in the aqueous phase and suggest that cooling slows solute diffusion through lipid membranes. This phenomenon appears to be related to the activation energy of each molecule between the aqueous and lipid phases rather than a phase change in the membrane. 3H2O seems to diffuse through aqueous regions of the air-perfusate barrier.

Immune response in BALB/c mice following immunization with heat-killed Mycobacterium lepraemurium

BALB/c mice were immunized with 1 X 10(7) heat-killed Mycobacterium lepraemurium (Mlm) via the hind foot pad. Four weeks later, the animals were infected with 1 X 10(9) Mlm intraperitoneally. Skin test studies, using footpad swelling as a parameter, indicated the development of skin reactivity to Mlm and M. leprae cell extracts. Immunized animals that were infected showed positive reactions to both antigens by the second week. This persisted up to fourteen weeks, at which time, bacillary restriction was also observed in the spleens and livers. Non-immunized infected animals, on the other hand showed a decline in skin reactivity to the two antigens used, and also showed proliferation of Mlm in the two organs examined. Animals receiving heat-killed Mlm or sensitized splenocytes when challenged with 5 X 10(3) M. leprae via hind foot pad, did not show inhibition of the infecting agent, thus indicating a lack of cross-protection.

Right atrial thrombus and superior vena cava syndrome in a child

Complications of central venous catheterization are well described. They include right atrial thrombosis and superior vena cava syndrome resulting from impaired venous drainage. Such complications are normally observed while the catheter is in place. They are often transient, resolving upon catheter removal. A patient with recurrent signs of superior vena caval obstruction 1 1/2 years after removal of the central venous catheter is described. The obstruction was determined to be intermittent and functionally related to elevated cardiac output due, in turn, to anemia. This patient was also found to have a calcific right atrial thrombus which was not obstructive.