bluuebunny/crossref_metadata_2025 huggingface dataset:
Cloning of and complementation tests with alkaline phosphatase regulatory genes (phoS and phoT) of Escherichia coli
Authors: Amemura M , Shinagawa H , Makino K , Otsuji N , Nakata A
Published: June 2021

The regulatory genes of alkaline phosphatase, phoS and phoT, of Escherichia coli were cloned on pBR322, initially as an 11.8-kilobase EcoRI fragment. A restriction map of the hybrid plasmid was established. Deletion plasmids of various sizes were constructed in vitro, and the presence of phoS and phoT genes on the cloned DNA fragments was tested by introducing the plasmids into phoS64 and phoT9 strains for complementation tests. One set complemented only phoS64 but not phoT9; the other set complemented only phoT9 but not phoS64. We conclude that phoS64 and phoT9 mutations belong to different complementation groups and probably to different cistrons. The hybrid plasmid with the 11.8-kilobase chromosomal fragment also complemented the phoT35 mutation. A smaller derivative of the hybrid plasmid was constructed in vitro which complemented phoT35 but did not complement phoS64, phoT9, or pst-2. Our results agree with the suggestion that phoT35 lies in a different complementation group from phoS, phoT, or pst-2 (Zuckier and Torriani, J. Bacteriol. 145:1249--1256, 1981). Therefore, we propose to designate phoT35 as phoU. The effect of amplification of phoS or phoT on alkaline phosphatase production was examined. It was found that multiple copies of the phoS gene borne on pBR322 repressed enzyme production even in low-phosphate medium, whether it was introduced into wild-type strains (partially repressed) or phoR (phoR68 or phoR17) strains (fully repressed), whereas the introduction of multicopy plasmids bearing the phoT gene did not affect the inducibility of the enzyme.
Expression of the activating enzyme and Fe protein of nitrogenase from Rhodospirillum rubrum
Authors: Triplett E W , Wall J D , Ludden P W
Published: June 2021

Activating enzyme (AE) is responsible for the in vitro activation of inactive Fe protein of nitrogenase from Rhodospirillum rubrum cells cultured anaerobically with glutamate as the N source. The expression of Fe protein and AE was examined in R. rubrum cultured photosynthetically or aerobically on media containing malate as the carbon source. One of the following N sources was used in each culture: glutamate, glutamine, limiting ammonia, high ammonia, glutamate plus histidine, and high ammonia plus histidine. Chromatophores from every culture exhibited AE activity; activity was highest in glutamate-grown cells. Fe protein was observed by rocket immunoelectrophoresis in cultures with nitrogenase activity. Several Nif-, Gln-, and His- mutants of R. rubrum were assayed for AE activity, nitrogenase activity, and Fe protein. Every mutant expressed AE activity, and Fe protein was observed in those cultures with nitrogenase activity. AE from every preparation was O2 labile, and each O2-denatured AE preparation inhibited activation by active AE.
Coupling of methyl coenzyme M reduction with carbon dioxide activation in extracts of Methanobacterium thermoautotrophicum
Authors: Romesser J A , Wolfe R S
Published: June 2021

The stimulation of carbon dioxide reduction to methane by addition of 2-(methylthio)ethanesulfonate (CH3-S-CoM) to cell extracts of Methanobacterium thermoautotrophicum was investigated. Similar stimulation of CO2 reduction by CH3-S-CoM was found for cell extracts of Methanobacterium bryantii and Methanospirillum hungatei. The CH3-S-CoM requirement could be met by the methanogenic precursors formaldehyde, serine, or pyruvate, or by 2-(ethylthio)ethanesulfonate (CH3CH2-S-CoM), but not by other coenzyme M derivatives. Efficient reduction of CO2 to CH4 was favored by low concentrations of CH3-S-CoM and high concentrations of CO2. Sulfhydryl compounds were identified as effective inhibitors of CO2 reduction. Both an allosteric model and a free-radical model for the mechanism of CO2 activation and reduction are discussed.
Growth inhibition by alpha-aminoadipate and reversal of the effect by specific amino acid supplements in Saccharomyces cerevisiae
Authors: Winston M K , Bhattacharjee J K
Published: June 2021

The growth of Saccharomyces cerevisiae wild-type strain X2180 in minimal medium was inhibited by the addition of higher-than-supplementary levels of alpha-aminoadipate. This inhibitory effect was reversed by the addition of arginine, asparagine, aspartate, glutamine, homoserine, methionine, or serine as single amino acid supplements. Mutants belonging to the lys2 and lys14 loci were able to grow in lysine-supplemented alpha-aminoadipate medium, although not as well as when selected amino acids were added. Growth in alpha-aminoadipate medium by all strains was accompanied by an accumulation of alpha-ketoadipate. Glutamate:keto-adipate transaminase levels were derepressed two- to fivefold in lys2 mutants using alpha-aminoadipate as a nitrogen source. Wild-type strain X2180 growing in amino acid-supplemented AA medium exhibited higher levels of alpha-aminoadipate reductase. Mutants unable to use alpha-aminoadipate without amino acid supplementation were obtained by treatment of lys2 strain MW5-64 and were shown to have glutamate: ketoadipate transaminase activity and to lack alpha-aminoadipate reductase activity. Altered cell morphologies, including increased size, multiple buds, pseudohyphae, and germ tubes, evidenced by cells grown in alpha-aminoadipate medium suggest that higher-than-supplementary levels of alpha-aminoadipate result in an impairment of cell division.
Variance of ploidy in Candida albicans
Authors: Suzuki T , Nishibayashi S , Kuroiwa T , Kanbe T , Tanaka K
Published: June 2021

Determination of ploidy was performed on isolates of Candida albicans from clinical sources by measuring nuclear DNA content with fluorescent microscope photometry. By this criterion and UV irradiation survival experiments, haploid, diploid, and tetraploid strains were identified in this organism. The dimensions of nucleus-associated organelles (equivalent to spindle pole bodies) in these strains increased as a function of ploidy number.
Nitrogen fixation (nif) genes and large plasmids of Rhizobium japonicum
Authors: Masterson R V , Russell P R , Atherly A G
Published: June 2021

The location of structural nitrogen-fixation genes was determined for the slow- and fast-growing types of Rhizobium japonicum. Slow-growing R. japonicum strains do not harbor structural nif genes, homologous to nifD and nifH, on large plasmids (100 to 200 megadaltons). In contrast, all fast-growing R. japonicum strains, except PRC194, contain structural nif genes on large plasmids.
UDP Glucuronate Decarboxylase and Synthesis of Capsular Polysaccharide in
Cryptococcus neoformans
Authors: Jacobson Eric S. , Payne William R.
Published: June 2021

UDP glucuronate decarboxylase activity was comparable in encapsulated and non-encapsulated strains of
Cryptococcus neoformans
, required NAD (

K
a

= 0.2 mM), and was inhibited by NADH (

K
i

= 0.1 mM) and UDP xylose.
Penicillin-binding proteins and carboxypeptidase/transpeptidase activities in Proteus vulgaris P18 and its penicillin-induced stable L-forms
Authors: Rousset A , Nguyen-Distèche M , Minck R , Ghuysen J M
Published: June 2021

The originally penicillin-induced, wall-less stable L-forms of Proteus vulgaris P18, isolated by Tulasne in 1949 and since then cultured in he absence of penicillin, have kept the ability to synthesize the seven penicillin-binding proteins and the various DD- and LD-peptidase activities found in the parental bacteria and known to be involved in wall peptidoglycan metabolism. The stable L-forms, however, secrete during growth both the highly penicillin-sensitive, DD-carboxy-peptidase-transpeptidase penicillin-binding protein PBP4 (which in normal bacteria is relatively loosely bound to the plasma membrane) and the penicillin-insensitive LD-carboxypeptidase (which in normal bacteria is located in the periplasmic region).
Multiple mechanisms for expression of incompatibility by broad-host-range plasmid RK2
Authors: Meyer R , Hinds M
Published: June 2021

By cloning fragments of plasmid DNA, we have shown that RK2 expresses incompatibility by more than one mechanism. One previously identified (R. J. Meyer, Mol. Gen, Genet. 177:155--161, 1979; Thomas et al., Mol. Gen. Genet. 181:1--7, 1981) determinant for incompatibility is linked to the origin of plasmid DNA replication. When cloned into a plasmid vector, this determinant prevents the stable inheritance of a coresident RK2. However, susceptibility to this mechanism of incompatibility requires an active RK2 replicon and is abolished if another replicator is provided. We have also cloned a second incompatibility determinant, encoded within the 54.1- to 56.4-kilobase region of RK2 DNA, which we call IncP-1(II). An RK2 derivative remains sensitive to IncP-1(II), even when it is not replicating by means of the RK2 replicon. The 54.1- to 56.4-kilobase DNA does not confer susceptibility to the IncP-1(II) mechanism, nor does it encode a detectable system for efficient plasmid partitioning. The incompatibility may be related to the expression of genes mapping in the 54.1- to 56.4-kilobase region, which are required for plasmid maintenance and suppression of plasmid-encoded killing functions.
2-pyrone-4,6-dicarboxylic acid, a catabolite of gallic acids in Pseudomonas species
Authors: Kersten P J , Dagley S , Whittaker J W , Arciero D M , Lipscomb J D
Published: June 2021

2-Pyrone-4,6-dicarboxylate hydrolase was purified from 4-hydroxybenzoate-grown Pseudomonas testosteroni. Gel filtration and electrophoretic measurements indicated that the preparation was homogeneous and gave a molecular weight of 37,200 for the single subunit of the enzyme. Hydrolytic activity was dependent upon a functioning sulfhydryl group(s) and was freely reversible; the equilibrium position was dependent upon pH, with equimolar amounts of pyrone and open-chain form present at pH 7.9. Since the hydrolase was strongly induced when the nonfluorescent organisms P. testosteroni and P. acidovorans grew with 4-hydroxybenzoate, it is suggested that 2-pyrone-4,6-dicarboxylate is a normal intermediate in the meta fission degradative pathway of protocatechuate. Laboratory strains of fluorescent pseudomonads did not metabolize 2-pyrone-4,6-dicarboxylate, but a strain of P. putida was isolated from soil that utilized this compound for growth; the hydrolase was then induced, but it was absent from extracts of 4-hydroxybenzoate-grown cells that readily catabolized protocatechuate by ortho fission reactions. 2-Pyrone-4,6-dicarboxylic acid was the major product formed when gallic acid was oxidized by purified protocatechuate 3,4-dioxygenase. Protocatechuate 4,5-dioxygenase gave only the open-chain ring fission product when gallic acid was oxidized, but the enzyme attacked 3-O-methylgallic acid, giving 2-pyrone-4,6-dicarboxylic acid as the major product. Cell suspensions of 4-hydroxybenzoate-grown P. testosteroni readily oxidized 3-O-methylgallate with accumulation of methanol.
Mapping of Streptococcus faecalis plasmids pAD1 and pAD2 and studies relating to transposition of Tn917
Authors: Clewell D B , Tomich P K , Gawron-Burke M C , Franke A E , Yagi Y , An F Y
Published: June 2021

Plasmids pAD1 (37.8 megadaltons) and pAD2 (17.1 megadaltons) of Streptococcus faecalis strain DS16 have been mapped with restriction enzymes. The location of a hemolysin-bacteriocin determinant on the conjugative pAD1 plasmid was derived from analyses of transposon insertions. Electron microscope and hybridization analyses located Tn917(Em) and the streptomycin (Sm) and kanamycin (Km) resistance determinants on the nonconjugative pAD2 plasmid. It was shown previously that the erythromycin (Em) resistance associated with Tn917 is inducible and that transposition from pAD2 to pAD1 is also stimulated by exposure of cells to low concentrations of Em. Here we show that inducing concentrations of Em also increase the conjugative transfer potential of pAD1; this is possibly related to a mild and short-lived inhibitory stress placed on the cells before full induction of resistance. Selection of Em-resistant transconjugants arising from matings between DS16 and a plasmid-free recipient gave rise to transconjugants which primarily harbor stable pAD1::pAD2 cointegrates. A 30-min exposure of donors to Em (0.5 microgram/ml) before mating resulted in a severalfold increase in the number of such transconjugants. However, a small fraction (e.g., 3 of 40) of these Emr Smr Kmr transconjugants harbored pAD1::Tn917 and pAD2 molecules. Since we believe pAD2 is incapable of being mobilized by pAD1 without being covalently linked, it is likely that transfer in these cases involved cointegrates representing structural intermediates in the transposition of Tn917 from pAD2 to pAD1. It follows that such intermediates probably had two copies of Tn917 and readily resolved after transfer. (These cointegrates are different from the stable cointegrates which were shown to have only a single copy of Tn917; the latter are assumed not to be related to transposition.) Two variants with altered Tn917 transposition properties were derived. One of them transposed at an elevated frequency, whereas the other showed no detectabel transposition. In neither case was transposition influenced by Em exposure; however, both remained inducible for Em resistance.
Cloning of the chromosomal determinants encoding hemolysin production and mannose-resistant hemagglutination in Escherichia coli
Authors: Berger H , Hacker J , Juarez A , Hughes C , Goebel W
Published: June 2021

We have cloned the chromosomal hemolysin determinants from Escherichia coli strains belonging to the four O-serotypes O4, O6, O18, and O75. The hemolysin-producing clones were isolated from gene banks of these strains which were constructed by inserting partial Sau3A fragments of chromosomal DNA into the cosmid pJC74. The hemolytic cosmid clones were relatively stable. The inserts were further subcloned either as SalI fragments in pACYC184 or as BamHI-SalI fragments in a recombinant plasmid (pANN202) containing cistron C (hlyC) of the plasmid-encoded hemolysin determinant. Detailed restriction maps of each of these determinants were constructed, and it was found that, despite sharing overall homology, the determinants exhibited minor specific differences in their structure. These appeared to be restricted to cistron A (hlyA), which is the structural gene for hemolysin. In the gene banks of two of these hemolytic strains, we could also identify clones which carried the genetic determinants for the mannose-resistant hemagglutination antigens Vb and VIc. Both of these fimbrial antigens were expressed in the E. coli K-12 clones to an extent similar to that observed in the wild-type strains. These recombinant cosmids were rather unstable, and, in the absence of selection, segregated at a high frequency.
Agrobacterium tumefaciens mutants affected in attachment to plant cells
Authors: Douglas C J , Halperin W , Nester E W
Published: June 2021

An analysis of Agrobacterium tumefaciens mutants with Tn5 insertions in chromosomal DNA showed that the chromosome of A. tumefaciens codes for a specific ability of this bacterium to attach to plant cells. This ability is associated with tumorigenesis by A. tumefaciens, the ability of avirulent A. tumefaciens to inhibit tumorigenesis, and the ability to adsorb certain phages. A second class of chromosomal mutations affects tumorigenesis without altering the ability to attach to plant cells. The attachment of A. tumefaciens to plant cells was assayed by mixing radiolabeled bacteria with suspensions of tobacco tissue culture cells or freshly isolated Zinnia leaf mesophyll cells. Under the conditions of this assay, an avirulent Ti plasmid-cured strain attached to the same extent as the same strain containing pTiB6806. Six of eight avirulent mutants with Tn5 insertions in chromosomal DNA showed defective attachment, whereas two retained wild-type attachment ability. In contrast to the strains showing wild-type attachment, the attachment-defective mutants failed to inhibit tumorigenesis when inoculated onto Jerusalem artichoke slices before inoculation of a virulent strain and also showed a loss of sensitivity to two Agrobacterium phages. The loss of phage sensitivity appeared to be due to a loss of ability to adsorb the phages. Staining with Calcofluor indicated that the mutants retained the ability to synthesize cellulose fibrils, which have been implicated in the attachment process. Southern filter hybridizations demonstrated that each mutant contained a single Tn5 insertion, and genetic linkage between the Tn5 insertion in one mutant and the attachment phenotype has also been demonstrated.
Cloning and characterization of Escherichia coli K-12 regulator gene tyrR
Authors: Cornish E C , Davidson B E , Pittard J
Published: June 2021

The Escherichia coli K-12 regulator gene tyrR was cloned into the multicopy plasmid pBR322 from a lambda(Tn10)tyrR+ specialized transducing phage. Further subcloning localized the gene within a 2.1-kilobase region. Analysis of plasmid-coded proteins showed that the tyrR gene codes for a 63,000-dalton polypeptide.
Preparation of acid-fast microscopy smears for proficiency testing and quality control
Authors: Smithwick R W , Stratigos C B
Published: June 2021

A method is presented for preparing smears for proficiency testing and quality control in acid-fast microscopy. The work was prompted by the increased demand for acid-fast bacilli positive smears with characteristic microscopic appearance and among-smear uniformity.
Evaluation of Port-A-Cul transport system for protection of anaerobic bacteria
Authors: Mena E , Thompson F S , Armfield A Y , Dowell V R , Reinhardt D J
Published: June 2021

The protection of anaerobes in Port-A-Cul (PAC) transport system (Bioquest, Div. of Becton, Dickinson &Co., Cockeysville, Md.) tubes and vials was studied. Ten species of obligately anaerobic bacteria commonly isolated from clinical specimens were used to prepare simulated swab and fluid specimens in high and low concentrations. Samples in PAC tubes and vials were held for 2, 24, and 48 h at ambient temperature and in a refrigerator. In addition, samples of the simulated specimens were exposed to controlled anaerobic and aerobic conditions in vented tubes and vials, with and without PAC medium, at ambient and refrigerator temperatures. Viable bacterial colony counts from specimens in PAC tubes and vials used as recommended by the manufacturer were consistently greater than those from specimens exposed to the different controlled conditions. The protection in PAC was about equal for specimens with either high or low concentrations of bacteria. Protection of the anaerobes in PAC was more obvious with swab than with fluid specimens. Quantitative recovery of anaerobes from refrigerated PAC samples, with few exceptions, was comparable to that from PAC samples held at ambient temperature.
Standardization of the Analytab Enteric (API 20E) system to increase accuracy and reproducibility of the test for biotype characterization of bacteria
Authors: Murray P R
Published: June 2021

Procedures employing the Analytab Enteric (API 20E) system were standardized to improve the accuracy and reproducibility of the individual biochemical tests so that the system could be used to biochemically characterize bacteria for epidemiological studies. The standardized method and the method recommended by the manufacturer (routine method) were tested in parallel with 130 clinical isolates. Tests with 100 randomly selected clinical isolates demonstrated that the standardized method was more accurate and reproducible than the routine method. In addition, the standardized method accurately identified 24 of 30 clinical isolates which could not be identified with the routine method.
Biotyping of Serratia marcescens and its use in epidemiological studies
Authors: Grimont P A , Grimont F
Published: June 2021

A Serratia marcescens biotyping system using eight carbon sources (benzoate, DL-carnitine, m-erythritol, 3-hydroxybenzoate, 4-hydroxybenzoate, lactose, D-quinate, and trigonelline), a tetrathionate reduction test, production of prodigiosin, and horse blood hemolysis was derived from a recent numerical taxonomic study (Grimont et al., J. Gen. Microbiol. 98:39-66, 1977). A total of 98.6% of 2,210 isolates from various sources could be assigned to 1 of 19 biotypes. Distribution and spread of 1,088 S. marcescens isolates throughout 13 clinical departments of Pellegrin Hospital (Bordeaux, France) were studied from 1968 through 1975. Except for one that colonized the intestinal tract of newborns, the six pigmented biotypes were seldom isolated. Each of the 13 nonpigmented biotypes showed a particular pattern of distribution and spread. The usefulness of S. marcescens biotyping was shown by relating several isolates recovered from patients and their inanimate environment and by pointing out the possible existence of infections or colonizations by two unrelated biotypes. S. marcescens strains isolated from the natural environment (water) are usually pigmented, and their biotypes are uncommon in hospitals. Biotyping can, therefore, be of help in epidemiological and ecological surveys.
Preparation of prereduced anaerobically sterilized media and their use in cultivation of anaerobic bacteria
Authors: Chan E C , deVries J , Harvey R F
Published: June 2021

Several modifications of the roll-tube method have made it simpler for routine use in the isolation and growth of anaerobic bacteria. These include use of a check valve for the production of prereduced anaerobically sterilized media; a Salvarsan tube under oxygen-free gas pressure for the dispensing of molten prereduced anaerobically sterilized agar medium; a Kelly infusion bottle with a graduated pipette side arm (also under gas pressure) for quantitative delivery of fluid prereduced anaerobically sterilized media; and screw-capped prescription bottles for the cultivation of anaerobes. Colonies of Bacteroides melaninogenicus were easily identified and counted by this method. Other anaerobic bacteria have also been cultivated successfully.
Rapid identification of Actinomycetaceae and related bacteria
Authors: Kilian M
Published: June 2021

Identification of new isolates belonging to the family Actinomycetaceae requires extensive numbers of biochemical tests, supplemented with gas-liquid chromatography determination of fermentation end products and, often, analysis of cell wall composition. This paper describes the results of the testing of 162 strains of Actinomycetaceae and related taxa for 20 different enzymatic activities including phosphatases, esterases, aminopeptidases, and glycosidases. The results of all tests were read after 4 h of incubation. The results obtained in the study provide significant new information on the biochemical properties of these groups of bacteria. An identification scheme based upon 13 selected tests, which allow the identification of these groups of bacteria within 4 h, is proposed.
Determination of human immunoglobulin M rheumatoid factor by a solid-phase radioimmunoassay which uses human immunoglobulin G in antigen-antibody complexes
Authors: Ziola B , Meurman O , Matikainen M T , Salmi A , Kalliomäki J L
Published: June 2021

A solid-phase radioimmunoassay for the rapid determination of human immunoglobulin M (IgM) rheumatoid factor (RF) has been developed. Preparation of the solid phase for the assay involved the formation of complexes between respiratory syncytial virus-specific human IgG antibodies and virus antigen on the surface of polystyrene balls. Binding of serum RF to IgG in the immune complex was subsequently detected by 125I-labeled mu-chain-specific antibodies to human IgM. The amount of radioactive indicator antibody bound was converted to units of RF by comparison to the standard curve for an RF reference-serum pool. This assay should prove useful in studies of the physiological role of RF, since it can effectively measure low levels of circulating RF.
Conjunctivitis due to adenovirus type 19
Authors: Taylor J W , Chandler J W , Cooney M K
Published: June 2021

An outbreak of unusual conjunctivitis occurred in Seattle in the summer of 1974. We found evidence of adenovirus type 19 (Ad19) infection in 28 of 42 (67%) referred cases from whom specimens for virus isolation and/or serology were obtained. Virus was isolated from conjunctiva, throats, and/or stools, often in week 2 of illness. Ad19-related cases more frequently had severe ocular pathology, transient visual impairment, and active disease for longer than a week. Secondary illnesses were more frequent in relation to Ad19 infection (26%) than to conjunctivitis of other etiology (5%, P less than 0.05). Persons with Ad19 infection commonly experienced sore throats without coughs or fevers. No common source of infection was identified in the outbreak, and illness was unrelated to occupation, residence, or family characteristics. A 3- to 8-day incubation period was suggested by two related cases.
Detection of cells producing surface antigen-specific antibody to influenza viruses
Authors: McLaren C , Grubbs G E , Ennis F A
Published: June 2021

B cells producing antibodies to influenza virus antigens were detected and quantitated by a hemolytic plaque assay. Responses of mice after primary infection and immunization with influenza viruses were measured and compared with responses after secondary immunization. The B-cell responses were specific and differentiated between A and B influenza viruses and between different subtypes of A influenza viruses. Responses to closely related influenza A virus strains of the H3N2 subtype cross-reacted but could also be differentiated. Cells secreting antibody to either of the virus surface antigens (hemagglutinin and neuraminidase) could be separately enumerated. Evidence that immunoglobulin G- secreting cells are detected in the assay without the use of facilitating anti-immunoglobulin G sera is presented.
Role of rotavirus (reo-like) in weanling diarrhea of pigs
Authors: Lecce J G , King M W
Published: June 2021

Piglets weaned abruptly and precociously at 3 weeks of age and placed in a crowded nursery commenced diarrhea 3 to 5 days later. Death losses were low (approximately 6%), but weight gain ceased for 2 weeks. Large numbers of rotavirus (reo-like) particles were seen by electron microscopy in diarrhetic fluids. Sections of intestines showed a loss of adsorptive surface in that villi were shortened and fused with adjacent villi. Immunofluorescence revealed rotaviral antigens within damaged enterocytes. Rotavirus-containing gut fluid was harvested from sick, weaned piglets. This fluid, filtered free of bacteria, was used to inoculate per os colostrum-deprived piglets. These infected piglets developed diarrhea and dehydration, and large numbers of rotaviral particles were seen in their diarrhetic fluid. Also, rotaviral antigens were present in aberrant enterocytes, and the intestinal villi were shortened. Since the weaned piglets (3 weeks old) came from sows that were providing their piglet's intestine with passive antibody protection via milk, we concluded that the abrupt removal of the piglet from the gut-bathing antibody combined with the stress of weaning produced a neonate vulnerable to the ubiquitous rotavirus. Similar circumstances may prevail and operate in exacerbating rotaviral diarrhea in neonates of other species of mammals.
Rapid test for acetyl-methyl-carbinol formation by Enterobacteriaceae
Authors: Qadri S M , Nichols C W , Qadri S G , Villarreal A
Published: June 2021

A modified Voges-Proskauer test is described which distinguishes within 4 to 8 hours between organisms that can produce acetyl-methyl-carbinol (acetoin) from glucose fermentation and those that cannot.
Factors affecting production of catalase by Bacteroides
Authors: Wilkins T D , Wagner D L , Veltri B J , Gregory E M
Published: June 2021

Several variables affected the production of catalase by members of the "Bacteroides fragilis group" of anaerobic bacteria. Both media yielded higher catalase levels than the respective agar media. Addition of hemin to media after autoclave sterilization, rather than before, significantly increased production of catalase. Both of these variables could be related to the available hemin concentration present in the medium being tested. Significantly higher amounts of hemin were required for catalase production than were required for growth. For catalase production by B. fragilis ATCC 25285, 1 microgram of hemin per ml was required. Of the various media tested, the use of chopped meat broth resulted in the highest levels of catalase production (up to 50 to 60 U of catalase per mg of protein). Of the various species and DNA homology groups tested, strains of B. fragilis and Bacteroides distasonis were catalase positive. Strains of Bacteroides thetaiotaomicron, Bacteroides ovatus, and Bacteroides eggerthi possessed variable catalase activity. Bacteroides vulgatus, Bacteroides uniformis, and DNA homology groups "3452A" and "subsp. a" were catalase negative. A catalase well test, in which equal volumes of 3% H2O2 and chopped meat culture are mixed, is described and recommended for routine catalase tests.
Immunodiagnosis of histoplasmosis in a compromised host
Authors: Land G A , Foxworth J H , Smith K E
Published: June 2021

Three serological tests for the diagnosis of histoplasmosis were compared for sensitivity and specificity in serum from blood bank donors, patients with histoplasmosis, and infected or noninfected immunosuppressed patients. The histoplasmin latex agglutination test was positive in 9% of the normal patients, 33% of the histoplasmosis patients, and 61% of the noninfected immunosuppressed patients. Since the test is prone to many false-positive results in patients with inflammatory diseases or non-Histoplasma infections, it has limited potential as a screening test among compromised patients. Immunodiffusion and counterimmunoelectrophoresis using a mycelial antigen were found to be more sensitive than either test using a combined yeast and mycelial antigen or a pure yeast phase antigen. Counterimmunoelectrophoresis at pH 7.2 proved to be the test of choice for serodiagnosis of histoplasmosis, resolving 85% of the immunocompetent infected patients and 100% of the infected immunosuppressed patients. Results indicated that counterimmunoelectrophoresis in conjunction with immunodiffusion could be used as a screening protocol to determine infection in incoming patients in a cancer hospital.
Immune response in urinary tract infection determined by radioimmunoassay and immunofluorescence: serum antibody levels against infecting bacterium and Enterobacteriaceae common antigen
Authors: Sanford B A , Thomas V L , Forland M , Carson S , Shelokov A
Published: June 2021

A solid-phase radioimmunoassay (RIA) procedure was compared with the indirect fluorescent antibody (IFA) test in a serological study of 76 female adults with urinary tract infections. Relative serum antibody activity was determined against patients' homologous infecting enterobacteria by RIA and IFA and against heterologous enterobacterial common antigen (Escherichia coli O14) by RIA. There was marked correlation between results of the IFA and RIA methods using the homologous system; 22 of 51 patients (43%) with pyelonephritis had significantly elevated serum antibody activity by both IFA (titers greater than or equal to 512) and RIA (binding ratio greater than or equal to 2.0) when compared with normal serum controls; three had significant antibody activity detectable by RIA only. Eighteen (72%) of 25 patients with pyelonephritis had RIA binding ratios of greater than or equal to 2.0 against their homologous bacterial isolates and the enterobacterial common antigen; an additional 6 patients had binding ratios of greater than or equal to 2.0 against the antigen only. All 25 patients with cystitis had low serum antibody levels by IFA and RIA when tested against their own isolate as well as enterobacterial common antigen. The RIA procedure was objective, quantitative, and less tedious to perform than IFA.
Counterimmunoelectrophoretic Detection of a High Incidence of Precipitin Reactions in Normal Human Sera Against Staphylococcal Teichoic Acids and Protein A
Authors: Leffell M. S. , Folds J. D. , Wasilauskas B.
Published: June 2021

The use of counterimmunoelectrophoresis (CIE) for detection of serum antibodies to staphylococcal teichoic acids was evaluated against teichoic acids prepared by sonic treatment or lysostaphin extraction of
Staphylococcus aureus
(Lafferty strain). Of 54 patient sera from suspected cases of staphylococcal endocarditis, osteomyelitis, or septicemia, 33 (61.1%) were positive by CIE analysis; however, 128 of 291 sera (44.0%) from normal adult donors were also positive. Selected CIE-positive sera from patient and control groups were titered by Ouchterlony gel diffusion. In the control group of normal sera, 65% were also positive by gel diffusion, but only 15% had titers of ≥1:2. Of the patient sera, 44.4% had gel diffusion titers of ≥1:2. In addition to the specific teichoic acid band, a second precipitation band could be demonstrated with both patient or normal sera by CIE or gel diffusion. This second precipitin band was shown to involve interactions of test sera with staphylococcal protein A present in the teichoic acid extracts. The protein A precipitins were detected at high concentrations of the antigen extracts, whereas the anti-teichoic acid precipitins were optimally detected at lower antigen concentrations. The formation of protein A precipitin bands did not correlate with the presence of anti-teichoic acid antibodies, as most sera tested were positive for protein A regardless of anti-teichoic acid activity. This study suggests that a high incidence of normal people have levels of antibodies to teichoic acids which are detectable by the highly sensitive, but nonspecific, technique of CIE.
Quality of Cary-Blair Transport Medium After Aging Nineteen Months
Authors: Morris George K. , Heck Jean
Published: June 2021

Cary-Blair medium retains its ability to serve as a transport medium after 19 months of aging at room temperature. This eliminates the necessity for the frequent replacement of the stored supplies of this medium.
Rapid micro-carbohydrate test for confirmation of Neisseria gonorrhoeae
Authors: Yong D C , Prytula A
Published: June 2021

A rapid carbohydrate utilization procedure for the confirmation of Neisseria gonorrhoeae and identification of other Neisseria species has been developed. This method utilizes both preformed enzymes, introduced in a heavy inoculum, and enzymes formed by the microorganisms as a result of growth in a small volume of super-enriched medium. Expected carbohydrate reactions were produced by 383 clinical isolates of neisseriae and were clearly visible within 4 h of incubation. The combined use of disposable glass tubes (6 by 50 mm) and microamounts of media (0.05 ml) make this method not only rapid, but also low in cost.
Cellular fatty acids of Flavobacterium meningosepticum and Flavobacterium species group IIb
Authors: Moss C W , Dees S B
Published: June 2021

The cellular fatty acid profiles of Flavobacterium meningosepticum and Flavobacterium species group IIb were markedly different from those of related bacteria. The profiles were characterized by the presence of 13-methyl-tetradecanoate and three uncommon acids: 2-hydroxy-13-methyl-tetradecanoate, 15-methyl-hexadecanoate, and 3-hydroxy-15-methyl-hexadecanoate.
Eosinophilic appendicitis due toStrongyloides stercoralis: a challenging differential diagnosis for clinicians
Authors: Páramo-Zunzunegui Javier , Rubio-López Laura , Benito-Barbero Silvia , Muñoz-Fernández Ángeles
Published: June 2021

A 45-year-old man presents with 48-hour status of high temperature, cough and dyspnoea. In the context of pandemic, the patient is initially diagnosed with COVID-19 syndrome. Later, the laboratory and ultrasound study supported acute appendicitis diagnosis. Appendicectomy was performed. The histopathology study confirmed eosinophilic appendicitis and that a parasitic infection was suspected. The stool sample was positive forStrongyloides stercoralis. The diagnosis of aS.stercoralisis a rare finding in Spain.S. stercoralissimulates clinical findings of inflammatory bowel disease or eosinophilic gastroenteritis, which may lead to the wrong therapeutic choice. Since in inflammatory diseases corticosteroid treatments are considered the initial choice in many cases, in the case ofS. stercoralisinfection, the administration of this therapy can be fatal. In Spain, the number of diagnoses is much lower than in the past decade, although it is highly probable that the infection has been underdiagnosed due to low clinical awareness among Spanish population.
Case of COVID-19-induced vestibular neuritis in a child
Authors: Giannantonio Sara , Scorpecci Alessandro , Montemurri Berardo , Marsella Pasquale
Published: June 2021

Since the outbreak of the COVID-19 pandemic, there has been a growing need to fully understand all the possible clinical features of the epidemic, which often presents with unusual manifestations, especially in children. In this report, we describe the case of a child with a COVID-19 infection and suffering exclusively from vertigo and fever. Altogether, considering the clinical manifestation, laboratory tests and imaging, given the patient’s positivity to SARS-CoV-2 infection and its neurotropic potential, we assumed that the child had COVID-19-induced vestibular neuritis, which, in consideration of the spontaneous improvement of symptoms, did not require any therapeutic adjustments, apart from the natural compensation of the central nervous system.This case suggests the importance of having an index of suspicion for a COVID-19 infection in patients with paediatrics presenting with vertigo and adds valuable information to the limited literature on COVID-19 presentation and management in children.
Recreational cannabis use causing non-ischaemic cardiomyopathy and cardioembolism in a young adult
Authors: Singh Budha O , Panda Prasan Kumar , Walia Rohit
Published: June 2021

Cannabis is one of the most common illicit drugs and has been implicated with various complications which include stroke, acute myocardial infarction, arrhythmia and limb arteritis. We are reporting a case of a young man, who is a recreational cannabis smoker along with tobacco, who developed exertional progressive breathlessness for the last 4 months, mild cough for 2 months and acute left-sided hemiparesis along with ipsilateral facial palsy for 1 day that was attributed to an acute right middle cerebral artery territory infarct. There was also gangrene in his left forearm as a result of left radial artery thrombosis. Non-ischaemic-dilated cardiomyopathy was found in contrast-enhanced cardiac MRI and he was managed in the line of decompensated heart failure; the right-hand gangrene was later amputated in the subsequent follow-ups. Hence, cannabis can lead to cardiomyopathy and resulting cardioembolism. The mainstay of management remains supportive and avoidance of the offending agent. Social education is the need of the hour.
‘Good’ and ‘Bad’ deaths during the COVID-19 pandemic: insights from a rapid qualitative study
Authors: Simpson Nikita , Angland Michael , Bhogal Jaskiran K , Bowers Rebecca E , Cannell Fenella , Gardner Katy , Gheewala Lohiya Anishka , James Deborah , Jivraj Naseem , Koch Insa , Laws Megan , Lipton Jonah , Long Nicholas J , Vieira Jordan , Watt Connor , Whittle Catherine , Zidaru-Bărbulescu Teodor , Bear Laura
Published: June 2021

Dealing with excess death in the context of the COVID-19 pandemic has thrown the question of a ‘good or bad death’ into sharp relief as countries across the globe have grappled with multiple peaks of cases and mortality; and communities mourn those lost. In the UK, these challenges have included the fact that mortality has adversely affected minority communities. Corpse disposal and social distancing guidelines do not allow a process of mourning in which families and communities can be involved in the dying process. This study aimed to examine the main concerns of faith and non-faith communities across the UK in relation to death in the context of the COVID-19 pandemic. The research team used rapid ethnographic methods to examine the adaptations to the dying process prior to hospital admission, during admission, during the disposal and release of the body, during funerals and mourning. The study revealed that communities were experiencing collective loss, were making necessary adaptations to rituals that surrounded death, dying and mourning and would benefit from clear and compassionate communication and consultation with authorities.
Journalists’ views on media coverage of medical tests and overdiagnosis: a qualitative study
Authors: O'Keeffe Mary , Nickel Brooke , Dakin Thomas , Maher Chris G , Albarqouni Loai , McCaffery Kirsten , Barratt Alexandra , Moynihan Ray
Published: June 2021

Objective

Promotional media coverage of early detection tests is an important driver of overdiagnosis. Following research evidence that global media coverage presents the benefits of testing healthy people far more frequently than harms, and gives little coverage to overdiagnosis, we sought to examine journalists’ views on media reporting of tests, overdiagnosis, and strategies to improve critical reporting on tests.

Design

Qualitative study using semistructured telephone interviews. Interviews were conducted between February and March 2020 and were audiorecorded and transcribed verbatim. Framework thematic analysis was used to analyse the data.

Participants and setting

Twenty-two journalists (mainly specialising in health reporting, average 14.5 years’ experience) based in Australia.

Results

This sample of journalists acknowledged the potential harms of medical tests but felt that knowledge of harms was low among journalists and the public at large. Most were aware of the term overdiagnosis, but commonly felt that it is challenging to both understand and communicate in light of strong beliefs in the benefits of early detection. Journalists felt that newsworthiness in the form of major public health impact was the key ingredient for stories about medical tests. The journalists acknowledged that factors, like the press release and ‘click bait culture’ in particular, can influence the framing of coverage about tests. Lack of knowledge and training, as well as time pressures, were perceived to be the main barriers to critical reporting on tests. Journalists felt that training and better access to information about potential harms would enable more critical reporting.

Conclusions

Effectively communicating overdiagnosis is a challenge in light of common beliefs about the benefits of testing and the culture of current journalism practices. Providing journalists with training, support and better access to information about potential harms of tests could aid critical reporting of tests.
Proton therapy for craniopharyngioma in adults: a protocol for systematic review and meta-analysis
Authors: Li Pengtao , Wang Jialing , Axier Aximujiang , Zhou Kai , Yun Jingwei , Wang Huayi , Zhang Tingrong , Li Shaoshan
Published: June 2021

Introduction

Craniopharyngioma is the most challenging to treat brain tumour with high recurrence rates, which can be effectively reduced by adjuvant radiotherapy. In recent years, proton therapy (PT), with its physical properties of heavy ion beam, that is, Prague peak phenomenon, has been more frequently used in patients with craniopharyngioma. Compared with conventional X-ray beam radiotherapy, PT can reduce the damage to normal tissues and enlarge the damage to tumours. Some studies have shown that PT has advantages in the treatment of craniopharyngioma in adults. However, the optimal management of craniopharyngioma remains controversial. The purpose of this study was to evaluate the efficacy and safety of PT for craniopharyngioma in adults.

Methods and analysis

We will search six databases (MEDLINE, EMBASE, Web of Science, the Cochrane Library, Amed, Scopus), clinical research registration websites and grey literature, aiming to identify randomised controlled trials (RCTs) on PT for craniopharyngioma in adults between 1 January 1954 and 28 September 2021. In the RCTs, PT will be used as the intervention group, and conventional X-ray beam radiotherapy will be used as the comparator group. Tumour recurrence and survival will be the primary outcome, and treatment-related toxicity will be the secondary outcome. The study selection, data extraction, bias risk and quality evaluation will be operated by two to four researchers independently. We will use Review Manager V.5.2 (RevMan V.5.2) for data analysis. If there is significant heterogeneity, we will identify the source of heterogeneity by subgroup analysis.

Ethics and dissemination

Our study is based on existing RCTs and does not require ethical approval. The results of the study will be published in a peer-reviewed journal or at a related conference.

PROSPERO registration number

CRD42020200909.
Acceptance and commitment therapy for young brain tumour survivors: study protocol for an acceptability and feasibility trial
Authors: Malins Sam , Owen Ray , Wright Ingram , Borrill Heather , Limond Jenny , Gibson Faith , Grundy Richard G , Bailey Simon , Clifford Steven C , Lowis Stephen , Lemon James , Hayes Louise , Thomas Sophie
Published: June 2021

Introduction

Survivors of childhood brain tumours have the poorest health-related quality of life of all cancer survivors due to the multiple physical and psychological sequelae of brain tumours and their treatment. Remotely delivered acceptance and commitment therapy (ACT) may be a suitable and accessible psychological intervention to support young people who have survived brain tumours. This study aims to assess the feasibility and acceptability of remotely delivered ACT to improve quality of life among these young survivors.

Methods and analysis

This study is a two-arm, parallel group, randomised controlled trial comparing ACT with waitlist control at 12-week follow-up as the primary endpoint. Seventy-two participants will be recruited, who are aged 11–24 and have completed brain tumour treatment. Participants will be randomised to receive 12 weeks of ACT either immediately or after a 12-week wait. The DNA-v model of ACT will be employed, which is a developmentally appropriate model for young people. Feasibility will be assessed using the proportion of those showing interest who consent to the trial and complete the intervention. Acceptability will be assessed using participant evaluations of the intervention, alongside qualitative interviews and treatment diaries analysed thematically. A range of clinical outcome measures will also assess physical and mental health, everyday functioning, quality of life and service usage at 12-week follow-up. The durability of treatment effects will be assessed by further follow-up assessments at 24 weeks, 36 weeks and 48 weeks.

Ethics and dissemination

Ethical approval was given by East Midlands, Nottingham 1 Research Ethics Committee (Reference: 20/EM/0237). Study results will be disseminated in peer-reviewed journals, through public events and relevant third sector organisations.

Trial registration

ISRCTN10903290;NCT04722237.