Susceptibility of Coxiella burnetii to chemical disinfectants.
Explore the source record for details and available documents.
Coxiella↗
Biomedical subjects
J C Williams
Publications and source records attributed to J C Williams.
Antigenic structure of Coxiella burnetii. A comparison of lipopolysaccharide and protein antigens as vaccines against Q fever.
The antigenic structure of Coxiella burnetii is being investigated by identifying both external and internal cellular epitopes of the morphologic cell types. Both the phase I lipopolysaccharide (LPSI) and several surface proteins are candidates for the development of subunit multivalent vaccines. The protective efficacy of purified LPSI was demonstrated in A/J mice. The purified LPSI preparations contained residual peptides detected by amino acid analysis. Therefore, the protection afforded by LPSI may be, in part, due to the presence of peptides. The purification of proteins free of LPSI must be accomplished before the protective efficacy of proteins or peptides can be established. We have identified three proteins that are both antigenic and immunogenic, as indicated by either enzyme immunoassay, radioimmunoprecipitation, immunoblot assay, or lymphocyte transformation. A 62-kDa protein antigen encoded by the htpB gene of C. burnetii was analyzed for immunogenicity. The purified protein antigen was immunogenic, as it elicited specific antibodies and performed as recall antigen in lymphocyte stimulation assays. The antigen was not detected on the surface of phase I cells but was highly represented on the surface of phase II cells. Therefore, the protein may not be a good candidate for vaccine development. The diagnostic utility of the 62-kDa protein antigen lies in the fact that convalescent and chronic Q fever sera from human patients reacted with the antigen, whereas acute sera did not. Although the 62-kDa protein is a "common antigen," specific peptide-based diagnostic reagents may be useful in the detection of Q fever disease progression. A major surface protein (P1) of roughly 29.5 kDa was purified from the phase I Nine Mile (clone 7) strain. No LPSI was detected in the P1 preparation by three different LPSI monoclonal antibodies. Monoclonal antibodies prepared against P1 were effective in localizing the protein on the cell surface, in the cell wall, and associated with the peptidoglycan of large cells of C. burnetii. Small, pressure-resistant cells did not contain P1. Mice immunized with two 25-micrograms injections of LPSI produced antibodies against LPSI and phase I whole cells. No antibody was detected against phase II whole cells. Immunization with P1 induced antibody against the LPSI fraction and phase I and phase II whole cells. P1 was more effective than LPSI in reducing the number of infectious C. burnetii in the spleens of challenged mice. The gene encoding another protein (P2) recognized by P1 monoclonal antibodies was cloned and sequenced.(ABSTRACT TRUNCATED AT 400 WORDS)
Animals↗
Characterization of Coxiella burnetii pyrB.
The C. burnetii pyrB gene was cloned on a 7-kbp EcoR I fragment. DNA sequence analysis, enzyme assays, and amino acid homologies with E. coli and B. subtilis pyrB gene products suggest that (i) C. burnetii ATCase exists as a trimer, (ii) the microorganism may not synthesize a regulatory polypeptide, and (iii) pyrB may be part of an operon whose expression is under the control of an upstream promoter. The high degree of homology of the active site further suggests that a common mechanism of catalysis for ATCase exists between such diverse organisms as C. burnetii, E. coli, and B. subtilis.
Amino Acid Sequence↗
Characterization of the origin of DNA replication of the Coxiella burnetii chromosome.
Explore the source record for details and available documents.
Chromosomes, Bacterial↗
The immune response in a cat-related outbreak of Q fever as measured by the indirect immunofluorescence test and the enzyme-linked immunosorbent assay.
The isotypic immune response of 16 individuals who developed Q fever pneumonia following exposure to an infected parturient cat was studied. The enzyme-linked immunosorbent (ELISA) test was used to detect IgM, IgA, and IgG antibodies to phase I and phase II Coxiella burnetii whole-cell antigens and to the phase I lipopolysaccharide. The indirect immunofluorescent antibody (IFA) test was also used to detect antibodies to phase I and phase II whole cells. None of the 16 subjects developed antibodies to the phase I lipopolysaccharide. The ELISA was more sensitive than the IFA test. IgM antibodies to phase II antigen were detectable by ELISA in 80% of the subjects at the time of onset of symptoms and were still present in 7 of the 8 tested at 32 weeks following the onset of symptoms. In all instances (ELISA: IgG, IgM; IFA: IgG, IgM) phase II antibodies developed earlier and reached higher levels than did phase I antibodies. The absence of antibodies to phase I lipopolysaccharide in acute Q fever combined with our unpublished findings of antibodies to phase I lipopolysaccharide in chronic Q fever suggests that this test may be used to distinguish acute from chronic Q fever.
Adult↗
Examination of the physical characteristics in a diverse group of dwarf White Leghorn pullets before and after first oviposition.
The purpose of the present experiment was to measure changes in physical variables with sexual maturity (SM), the oviposition of first egg, in sex-linked dwarf pullets when SM was delayed by the photoschedule. Offspring were produced from matings of dwarf Single Comb White Leghorn chickens divergently selected for high (H) or low (L) 20-wk BW. At 15 wk of age, pullets from half-sibling sets were randomly assigned to a diet either of low energy (LE: 2,500 kcal/kg of ME, 15% CP) or high energy (HE: 3,000 kcal/kg of ME, 15% CP) and were placed in cages. When a pullet reached SM, the mature (M) pullet and an immature (I, absence of oviposition), half-sibling pullet on the same diet were sampled for BW as well as for the weights of abdominal fat, liver, ovary, oviduct, whole egg (M pullets), yolk, and shell and for the number of rapidly developing follicles. Proximate measurements (wet weight) were made for defeathered carcasses and livers as well as for ovaries and oviducts. There were significant (P less than or equal to .01) line effects for BW at SM (H greater than L); age at SM (L greater than H); weights for the liver, abdominal fat, egg, albumen, shell (H greater than L), and yolk (L greater than H); number of developing follicles (H greater than L); percentage of carcass protein (L greater than H) and of fat (H greater than L); as well as for liver protein (L greater than H), fat (H greater than L), and ash (L greater than H). There were significant (P less than .01) diet effects for abdominal fat (HE greater than LE) and shell weight (LE greater than HE). There was a line-by-diet interaction for total feed intake and for total energy intake from 15 wk to oviposition of the first egg. There were significant (P less than .01) SM effects (M greater than I) for BW at SM, number of developing follicles, oviduct weight, and fat content of the reproductive organs; also, reproductive organ weights accounted for differences in BW at SM. There was an interaction for line by maturity state; the L pullets showed a greater increase in ovarian weight with oviposition of the first egg than did the H pullets. The results of this study indicated that the threshold requirements for BW, composition, or both, for SM may have been exceeded in Leghorn-type chickens when photoscheduling was used to delay the onset of SM.
Abdomen↗
Effects of ivermectin and fenbendazole in strategic treatment of gastrointestinal nematode infections in cattle.
Four groups of 18 beef calves each were used to evaluate effects of different treatments on parasite control and weight gains. The investigation extended from November 1986 (weaning) to October 1987. Group-1 calves were treated with ivermectin (200 micrograms/kg of body weight, SC) at approximately 6-week intervals for a total of 8 treatments; group-2 calves were given the same dosage of ivermectin by the same route of administration as group-1 calves in November, March, and July; group-3 calves were given fenbendazole paste (5 mg/kg, PO) at the same times as group-2 calves; and group-4 calves served as untreated controls with provision for ivermectin salvage treatment. All groups grazed on individual pairs of larval-contaminated, 1.6-ha pastures. Highest (P less than 0.05) initial worm counts in fall tracer calves were found in group 3 (Ostertagia ostertagi and Trichostrongylus axei adults) and group 4 (O ostertagi and Haemonchus adults). Fecal egg counts of group-1 calves were low throughout the experiment and pasture larval counts remained negligible after July. Egg counts and larval counts of other groups remained higher into summer. Worm counts, including O ostertagi inhibited early fourth-stage larvae (EL4), were highest (P less than 0.05) in groups-3 and -4 spring tracer calves; numbers of O ostertagi EL4 were similarly high in groups 2, 3, and 4; and T axei counts were highest (P less than 0.05) in groups-3 and -4 yearlings slaughtered in spring. Liveweights of group-1 calves were greater (P less than 0.05) than in other groups from March 2 to October, and by July 2, group-2 calves had a liveweight advantage over group-4 calves. Group-3 calves had the lowest rate of gain from March to July and mean liveweight of the group was less (P less than 0.05) than in all other groups from April to October. Only minimal worm numbers were recovered from groups-1 or -2 calves in October. Large numbers of O ostertagi and T axei were recovered from group-4 calves and O ostertagi from group-3 calves. A few calves in groups 3 and 4, but particularly in group 4, were affected by type-II disease (chronic to acute gastritis caused by maturation and emergence of previously inhibited larvae) from August to October. Final mean liveweights in descending order were 365 kg in group 1, 328 kg in group 2, 316 kg in group 4, and 281 kg in group 3.
Animals↗
Efficacy of concomitant early summer treatment with fenbendazole and clorsulon against Fasciola hepatica and gastrointestinal nematodes in calves in Louisiana.
The efficacy, safety, and compatibility of fenbendazole (FBZ) and clorsulon (CLN) were tested after oral administration of label recommended and of higher (5x) dosage rates to calves naturally infected with gastrointestinal nematodes and Fasciola hepatica. Results for 42 calves allotted to 4 treatment groups indicated a similar efficacy against mature F hepatica by FBZ (5 mg/kg of body weight) and CLN (7 mg/kg) in a combined oral suspension, compared with CLN (7 mg/kg) alone (100 vs 99% reduction). A lesser efficacy was observed against immature flukes (88.6 and 84.9% reduction, respectively). Calves given 25 mg of FBZ/kg and 35 mg of CLN/kg had nearly complete reduction of both mature (99.6%) and immature flukes (99.1%). Fasciola egg counts were reduced by greater than 99.5% in all treated groups. Against Ostertagia ostertagi, the percentage of efficacy of the combined FBZ (5 mg/kg) and CLN (7 mg/kg) treatment was 94.3% against adults and 81.3% against inhibited larvae. Efficacy against all other nematodes was 100%, except against Cooperia spp adults (98.3%) and immature Oesaphagostomum radiatum (88.0%). At 5 x dosage rates for FBZ and CLN, percentage of removal of adults and inhibited larvae of O ostertagi was 99.3 and 99.0%, respectively, and 99 to 100% for other nematodes. Results indicate that FBZ and CLN are compatible when mixed together and administered as an oral suspension to cattle and that the efficacy is similar to that of the drugs individually. On the basis of further results, we suggest that summer treatment may be superior in preventive value for gastrointestinal nematodes and F hepatica, compared with spring treatment, because of seasonal infection dynamics of the major cattle parasites in Louisiana.
Animals↗
Genomic imprinting and the Beckwith-Wiedemann syndrome.
Explore the source record for details and available documents.
Beckwith-Wiedemann Syndrome↗
Prenatal genetic diagnosis following recurrent early pregnancy loss.
Recurrent pregnancy loss affects 1% of patients, an incidence higher than expected from the prevalence of spontaneous abortion in the general population. Some couples may show a tendency for aneuploid conceptions. Genetic counseling and amniocentesis or chorionic villus sampling were offered to 305 couples with a history of two or more pregnancy losses and normal parental karyotypes, with no additional known risk factors for aneuploidy. Prenatal diagnostic procedures were performed in 96 pregnancies. Two hundred nine couples declined active intervention, and these pregnancies were followed to delivery. Five chromosomal abnormalities (1.6%) were diagnosed in the study group. A group of 979 prenatal diagnostic procedures performed in "low-risk" pregnancies in Hutzel Hospital was used as controls, and three chromosomal anomalies (0.3%) were diagnosed. That the rate of aneuploid conceptions was statistically significantly (P = .02) higher in low-risk couples experiencing recurrent pregnancy loss than in controls points to a tendency for chromosomal aberrations in their offspring and suggests a place for prenatal diagnosis in subsequent pregnancies.
Abortion, Habitual↗
Maternal allele loss in Wilms' tumour.
Explore the source record for details and available documents.
Alleles↗
Genetic evidence for superoperonal organization of genes for photosynthetic pigments and pigment-binding proteins in Rhodobacter capsulatus.
Three adjacent operons, each concerned with photosynthesis in Rhodobacter capsulatus, have been shown by genetic means to be cotranscribable. In the course of describing the characteristics of the bchCA operon, which encodes two enzymes essential for bacteriochlorophyll synthesis, we found that the expression of the bchCA genes is influenced by readthrough from the upstream crtE and crtF genes. The crtE and crtF genes encode enzymes required for carotenoid biosynthesis and function as an operon. Furthermore, the distal structural gene of the bchCA operon, bchA, contains within it both the major oxygen-regulated promotor (Ppuf1) and the constitutive (Ppuf2) promotor for the puf operon. Since these three operons, crtEF, bchCA, and puf, are all transcribed in the same direction, it appears that polymerases traversing the downstream regions may start at any of several promoters. This pattern of transcription, which is unusual among bacteria, demonstrates that the activities of individual operons in a superoperonal cluster may be affected by their positions within the cluster.
Amino Acid Sequence↗
Neurological deterioration in adult phenylketonuria.
A 28-year-old man with classical phenylketonuria had increased seizure frequency and rapidly progressive spasticity. There was a marked reduction of biogenic amine neurotransmitter metabolites in cerebrospinal fluid. Dietary therapy reduced serum phenylalanine levels, improved symptoms of hypertonicity, and cerebrospinal fluid neurotransmitter metabolites became normal. An adolescent male with classical phenylketonuria, treated by dietary restriction until age 6 years, was assessed for decreasing school performance at 18 years. Cerebrospinal fluid biogenic amine neurotransmitter metabolites were significantly reduced. Magnetic resonance imaging in both subjects showed multiple areas of increased signal intensity in cerebral white matter. Neuropathological changes in classical phenylketonuria have been characterized as a dysmyelinating or demyelinating process. Neurochemical studies show a defect in brain lipids and biogenic amine metabolism. In the past, dietary therapy was directed at reducing hyperphenylalaninaemia only during the first decade of life. This report, as well as other studies, indicates that dietary therapy should be lifelong in patients with classical phenylketonuria, in order to prevent progressive and insidious neurological deterioration in later life.
Adolescent↗
Epidemiology of Dictyocaulus viviparus in Louisiana (U.S.A.).
An epidemiological investigation was conducted during a 1-year period on a permanent pasture naturally contaminated with Dictyocaulus viviparus and grazed by a varying number of yearling cattle. Seasonal variation in pasture infectivity to cattle was monitored by monthly slaughter of tracer calves, slaughter of pairs of resident yearlings at 30-60-day intervals, herbage larval recovery and by counts of first stage larvae in feces (modified Baermann technique) of resident cattle. A clinical outbreak of dictyocauliasis occurred during January-March 1986 and was associated with peak levels of pasture infectivity. Carrier animals were considered responsible for the survival of infection over summer. Although soil samples were taken regularly on a monthly basis to study the epidemiological importance of the soil as a source of infection, infective larvae were not recovered at any time. The epidemiological pattern observed in the present study provides basic information on the factors involved in infection and diseases outbreaks under sub-tropical conditions.
Animals↗
Three treatments with ivermectin in year-long control of gastrointestinal nematode parasites of weaner-yearling beef cattle.
Four groups of 17 crossbred beef weaners were used in an experiment which extended from 14 November 1985 to 8 October 1986 (328 days). All groups began grazing on separate, contaminated pastures at a stocking rate of 5.3 cattle ha-1 and the different treatments were: Group 1, ivermectin (IVM) injectable X 1 (200 micrograms kg-1) on 14 November only, with provision for individual salvage treatment; Group 2, IVM X 3 on 14 November, 4 February and 2 July; Group 3, IVM X 2 on 14 November and 2 July; Group 4, fenbendazole (FBZ) paste X 2 (5 mg kg-1) on 14 November and 2 July. Pairs of parasite-free tracer calves were grazed on all group pastures for 1 month at the beginning of the experiment (13 November-12 December and in spring (1 April-1 May). Yearling cattle from each group were randomly selected and removed from pasture during spring (n = 2 per group, 3 April) and at the end of the experiment (n = 3 per group, 8 October) for slaughter analysis of worm population characteristics and observation of gross pathology in the abomasum and intestinal tract. At monthly intervals, all cattle were weighed and fecal egg counts, pasture larval counts and plasma pepsinogen values were determined. The results of this investigation demonstrated that three IVM treatments of weaner-yearling beef cattle during year-long grazing, were more effective than a single IVM treatment or two treatments with IVM or FBZ in the enhancement of productivity and protection from the effects of infection with nematode parasites.
Animals↗
Urine glyceraldehyde excretion is elevated in the renal Fanconi syndrome.
We analyzed urinary constituents using GC/MS in 16 children with the renal Fanconi syndrome and 13 normal individuals. Urine glyceraldehyde levels were strikingly elevated in the renal Fanconi syndrome group (mean 5.1 +/- 4.8 mg/mg creatinine) compared to levels in the normal group (mean 0.04 +/- 0.04 mg/mg creatinine, P less than 0.001). Urine lactate levels were also elevated in the renal Fanconi syndrome group (mean 2.3 +/- 2.6 mg/mg creatinine) compared to normals (mean 0.01 +/- 0.01 mg/mg creatinine, P less than 0.003). Only small elevations of glyceraldehyde and lactate were found in urine from children with other renal disorders. Serum levels of glyceraldehyde and lactate were no greater in individuals with the Fanconi syndrome than in the normals. The fractional reabsorption of both glyceraldehyde and lactate was virtually complete in the normals, but was markedly impaired in the Fanconi syndrome patients where, in some cases, glyceraldehyde excretion greatly exceeded the excretion of creatinine. We conclude that marked glyceraldehyde excretion is a previously unrecognized feature of the renal Fanconi syndrome which may result from disordered proximal tubular glycolytic metabolism. Further studies will be required to determine the role of glyceraldehyde loss in the pathogenesis of this generalized disturbance of proximal tubular function.
Child↗
Energy metabolism of monocytic Ehrlichia.
We investigated if the monocytic Ehrlichia are totally dependent on their host cells for energy, or, as Rickettsia, are capable of some ATP synthesis in vitro. The Miyayama strain of Ehrlichia sennetsu and the Maryland and Illinois strains of Ehrlichia risticii were cultivated in a mouse macrophage cell line, separated from host cell constituents by procedures that included Renografin or Percoll gradient centrifugation, and tested after cryopreservation. Cells incubated without a metabolizing substrate contained little, if any, ATP. When the Ehrlichia cells were incubated for 1 hr at 34 degrees C with glutamine, significant amounts of ATP were detected. The amounts of ATP attained with glutamine were decreased in some instances by the addition of atractyloside, an inhibitor of adenine nucleotide translocase in mitochondria, and were decreased consistently and to a greater extent by 2,4-dinitrophenol. When ATP, instead of glutamine, was added to the ehrlichiae, upon incubation the amount of ATP was markedly decreased. Comparable responses under all these conditions were obtained with Rickettsia typhi, although the final ATP levels were higher. Control preparations derived from uninfected mouse macrophages or from the discards of the Ehrlichia purification procedures contained negligible amounts of ATP, which were not increased by incubation with glutamine. We conclude that with respect to ATP metabolism, the monocytic Ehrlichia resemble Rickettsia more closely than Chlamydia, even though Ehrlichia resemble Chlamydia in their intracellular location in the phagosomes and in possibly having a developmental cycle.
2,4-Dinitrophenol↗
Inactivation of Coxiella burnetii by gamma irradiation.
The gamma radiation inactivation kinetics for Coxiella burnetii at -79 degrees C were exponential. The radiation dose needed to reduce the number of infective C. burnetii by 90% varied from 0.64 to 1.2 kGy depending on the phase of the micro-organism, purity of the culture and composition of suspending menstruum. The viability of preparations containing 10(11) C. burnetii ml-1 was completely abolished by 10 kGy without diminishing antigenicity or ability to elicit a protective immune response in vaccinated mice. Immunocytochemical examinations using monoclonal antibodies and electron microscopy demonstrated that radiation doses of 20 kGy did not alter cell-wall morphology or cell-surface antigenic epitopes.
Animals↗