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Abstract Background Deep-level second generation sequencing (2GS) technologies are now being applied to non-model species as a viable and favourable alternative to Sanger sequencing. Large-scale SNP discovery was undertaken in blackcurrant (Ribes nigrum L.) using transcriptome-based 2GS 454 sequencing on the parental genotypes of a reference mapping population, to generate large numbers of novel markers for the construction of a high-density linkage map. Results Over 700,000 reads were produced, from which a total of 7,000 SNPs were found. A subset of polymorphic SNPs was selected to develop a 384-SNP OPA assay using the Illumina BeadXpress platform. Additionally, the data enabled identification of 3,000 novel EST-SSRs. The selected SNPs and SSRs were validated across diverse Ribes germplasm, including mapping populations and other selected Ribes species. SNP-based maps were developed from two blackcurrant mapping populations, incorporating 48% and 27% of assayed SNPs respectively. A relatively high proportion of visually monomorphic SNPs were investigated further by quantitative trait mapping of theta score outputs from BeadStudio analysis, and this enabled additional SNPs to be placed on the two maps. Conclusions The use of 2GS technology for the development of markers is superior to previously described methods, in both numbers of markers and biological informativeness of those markers. Whilst the numbers of reads and assembled contigs were comparable to similar sized studies of other non-model species, here a high proportion of novel genes were discovered across a wide range of putative function and localisation. The potential utility of markers developed using the 2GS approach in downstream breeding applications is discussed.

Abstract Background The detrimental effects of mild winter temperatures on the consistency of cropping of blackcurrant (Ribes nigrum L.) in parts of Europe have led to increasing interest in the genetic control of dormancy release in this species. This study examined patterns of gene expression in leaf buds of blackcurrant to identify key differential changes in these profiles around the time of budbreak. Results Using leaf bud tissue of blackcurrant, a cDNA library was generated as a source of blackcurrant ESTs for construction of a custom microarray, which was used to identify differential gene expression during dormancy release. Gene activity was lowest in early stages of dormancy, increasing to reach a maximum around the time of budbreak. Genes with significantly changing expression profiles were clustered and evidence is provided for the transient activity of genes previously associated with dormancy processes in other species. Expression profiling identified candidate genes which were mapped onto a blackcurrant genetic linkage map containing budbreak-related QTL. Three genes, which putatively encode calmodulin-binding protein, beta tubulin and acetyl CoA carboxylase respectively, were found to co-localise with budbreak QTL. Conclusions This study provides insight into the genetic control of dormancy transition in blackcurrant, identifying key changes in gene expression around budbreak. Genetic mapping of ESTs enabled the identification of genes which co-localise with previously-characterised blackcurrant QTL, and it is concluded that these genes have probable roles in release of dormancy and can therefore provide a basis for the development of genetic markers for future breeding deployment.

Ticks represent important vectors of a number of bacterial and viral disease agents, owing to their hematophagous nature and their questing behavior (the process in which they seek new hosts). Questing activity is notably seasonal with spatiotemporal dynamics that needs to be understood in detail as part of mediating and mitigating tick-borne disease risk. Models of the geography of tick questing activity developed to date, however, have ignored the temporal dimensions of that behavior; more fundamentally, they have often not considered the sampling underlying available occurrence data. Here, we have addressed these shortfalls for Amblyomma americanum, the most commonly encountered tick in the central Great Plains, via (1) detailed, longitudinal sampling to characterize the spatiotemporal dimensions of tick questing activity; (2) randomization tests to establish in which environmental dimensions a species is manifesting selective use; and (3) modeling methods that include both presence data and absence data, taking fullest advantage of the information available in the data resource. The outcome was a detailed picture of geographic and temporal variation in suitability for the species through the two-year course of this study. Such models that take full advantage of available information will be crucial in understanding the risk of tick-borne disease into the future., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Cobos et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Bacterial infections caused by Gram-negative pathogens, such as those in the family Enterobacteriaceae, are among the most difficult to treat because effective therapeutic options are either very limited or non-existent. This raises serious concern regarding the emergence and spread of multi-drug resistant (MDR) pathogens in the community setting; and thus, creates the need for discovery efforts and/or early-stage development of novel therapies for infections. Our work is directed towards branched polyethylenimine (BPEI) modified with polyethylene glycol (PEG) as a strategy for targeting virulence from Gram-negative bacterial pathogens. Here, we neutralize lipopolysaccharide (LPS) as a barrier to the influx of antibiotics. Data demonstrate that the β-lactam antibiotic oxacillin, generally regarded as ineffective against Gram-negative bacteria, can be potentiated by 600 Da BPEI to kill some Escherichia coli and some Klebsiella pneumoniae. Modification of 600 Da BPEI with polyethylene glycol (PEG) could increase drug safety and improves potentiation activity. The ability to use the Gram-positive agent, oxacillin, against Gram-negative pathogens could expand the capability to deliver effective treatments that simplify, reduce, or eliminate some complicated treatment regimens., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Charles V. Rice reports financial support was provided by National Institutes of Health., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Odocoileus virginianus (white-tailed deer) is the primary host of adult Ixodes scapularis (deer tick). Most of the research into I. scapularis has been geographically restricted to the northeastern United States, with limited interest in Oklahoma until recently as the I. scapularis populations spread due to climate change. Ticks serve as a vector for pathogenic bacteria, protozoans, and viruses that pose a significant human health risk. To date, there has been limited research to determine what potential tick-borne pathogens are present in I. scapularis in central Oklahoma. Using a one-step multiplex real-time reverse transcription-PCR, I. scapularis collected from white-tailed deer was screened for Anaplasma phagocytophilum , Borrelia burgdorferi , Borrelia miyamotoi , Babesia microti , and deer tick virus (DTV). Ticks ( n  = 394) were pooled by gender and life stage into 117 samples. Three pooled samples were positive for B. miyamotoi and five pooled samples were positive for DTV. This represents a minimum infection rate of 0.8% and 1.2%, respectively. A. phagocytophilum , B. burgdorferi , and B. microti were not detected in any samples. This is the first report of B. miyamotoi and DTV detection in Oklahoma I. scapularis ticks. This demonstrates that I. scapularis pathogens are present in Oklahoma and that further surveillance of I. scapularis is warranted.

For the past 30 years, the number of people infected with causative agents of ehrlichiosis, Rocky Mountain spotted fever, and spotted fever group rickettiosis (SFGR) has increased in Oklahoma. However, there is a lack of data on pathogen prevalence within urban environments. To assess the prevalence of tick-borne pathogens in different environments, 434 Amblyomma americanum (lone star) ticks were collected from the environment in two parks in Edmond, Oklahoma. The presence of Ehrlichia spp. and spotted fever group (SFG) Rickettsia spp. was determined using quantitative real-time polymerase chain reaction (qPCR). 33.6% (146/434) of the A. americanum ticks were positive for Rickettsia amblyommatis and 15.2% (66/434) were positive for Ehrlichia chaffeensis . No ticks were positive for other SFG Rickettsiae ( R. rickettsii, R. parkeri ) or other Ehrlichiae ( E. ewingii, and Panola Mountain Ehrlichia ). These studies provide increased understanding of the potential risk for encountering tick-borne pathogens in urban environments.

Infections from antibiotic-resistant Staphylococcus aureus and Pseudomonas aeruginosa are a serious threat because reduced antibiotic efficacy complicates treatment decisions and prolongs the disease state in many patients. To expand the arsenal of treatments against antimicrobial-resistant (AMR) pathogens, 600-Da branched polyethylenimine (BPEI) can overcome antibiotic resistance mechanisms and potentiate β-lactam antibiotics against Gram-positive bacteria. BPEI binds cell-wall teichoic acids and disables resistance factors from penicillin binding proteins PBP2a and PBP4. This study describes a new mechanism of action for BPEI potentiation of antibiotics generally regarded as agents effective against Gram-positive pathogens but not Gram-negative bacteria. 600-Da BPEI is able to reduce the barriers to drug influx and facilitate the uptake of a non-β-lactam co-drug, erythromycin, which targets the intracellular machinery. Also, BPEI can suppress production of the cytokine interleukin IL-8 by human epithelial keratinocytes. This enables BPEI to function as a broad-spectrum antibiotic potentiator, and expands the opportunities to improve drug design, antibiotic development, and therapeutic approaches against pathogenic bacteria, especially for wound care., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Various ecological and economical concerns have spurred mankind's quest for materials that can provide enhanced weight savings and improved fuel efficiency. As part of this pursuit, we have microstructurally tailored an exceptionally high-strength titanium alloy, Ti-6Al-2Sn-4Zr-6Mo (Ti6246) through friction stir processing (FSP). FSP has altered the as-received bimodal microstructure into a unique modulated microstructure comprised of fine acicular α″-laths with nano precipitates within the laths. The sequence of phase transformations responsible for the modulated microstructure and consequently for the strength is discussed with the help of scanning electron microscopy, transmission electron microscopy, and synchrotron X-ray diffraction studies. The specific strength attained in one of the conditions is close to 450 MPa m 3 /mg, which is about 22% to 85% greater than any commercially available metallic material. Therefore, our novel nano particle strengthened Ti alloy is a potential replacement for many structural alloys, enabling significant weight reduction opportunities.

In recent years, human tick-borne disease occurrence has risen in Oklahoma, U.S.A., but year-round data on tick presence in frequently used recreational areas is not widely available. In this study, ticks were collected monthly for one year at residential and non-residential sites in a suburban area of Oklahoma County, OK, U.S.A. At each trapping site, dry ice traps were used in both woodland and grassland areas and fabric tick drags were used in grassland areas. Four species were collected from each park: Amblyomma americanum, Amblyomma maculatum, Dermacentor variabilis, and Ixodes scapularis. Prior to this study, A. americanum was the only species with an established population in Oklahoma County. Consistent with this, A. americanum was collected in all months of the year and accounted for over 90% of ticks collected at each site. Based on our tick survey, we report that A. maculatum, D. variabilis, and I. scapularis, which were each collected in numbers greater than six within a single sampling occasion, are now each confirmed as established populations in Oklahoma County., (© 2019 The Society for Vector Ecology.)

Trypanosoma cruzi is a vector-borne protozoan parasite that infects seven million individuals in Central and South America and is the etiologic agent of Chagas disease. There are increasing reports of endemic transmission within the southern US. Trypanosoma cruzi occurs in wild raccoons and dogs in Oklahoma, but its endemicity in the state is poorly studied. We suspected Mexican free-tailed bats ( Tadarida brasiliensis) contributed to the endemicity of T. cruzi in Oklahoma due to their annual migration from Central America to their North American maternity roosts. During the summer of 2017, we sampled 361 Mexican free-tailed bats for T. cruzi at three maternity roosts in Oklahoma. We collected wing tissues, extracted T. cruzi DNA, amplified target DNA by PCR using the primers TCZ1/TCZ2, and observed amplification by gel electrophoresis. One juvenile Mexican free-tailed bat was positive for T. cruzi resulting in a 0.27% prevalence in the 361 sampled bats. Our finding of a wild bat naturally infected with T. cruzi in Oklahoma provided insight on the endemicity of T. cruzi in underrepresented endemic areas. The positive sample was sequenced, confirmed as T. cruzi, and uploaded to GenBank (no. MG869732). Future research will focus on monitoring T. cruzi prevalence in wild bats and insect vectors to better understand the enzootic emergence of this neglected tropical parasite.

A doped non-diamagnetic alumina (Al 2 O 3 ) would enable the usage of cutting edge technology, such as magnetoforming, to create advanced systems that take advantage of the high chemical and physical resilience of alumina. This study elucidates the magnetic properties of Cr, Fe, Ni, and Cu doped α- and ϑ-alumina. Density functional theory was used to predict the structural, electronic, and magnetic properties of doped alumina, as well as its stability. The results indicate that the dopant species and coordination environment are the most important factors in determining the spin density distribution and net magnetic moment, which will strongly direct the ability of the doped alumina to couple with an external field. Similar coordination environments in different phases produce similar spin densities and magnetic moments, indicating that the results presented in this work may be generalizable to the other five or more phases of alumina not studied here.

The potential of high-entropy alloys (HEAs) to exhibit an extraordinary combination of properties by shifting the compositional regime from the corners towards the centers of phase diagrams has led to worldwide attention by material scientists. Here we present a strong and ductile non-equiatomic HEA obtained after friction stir processing (FSP). A transformation-induced plasticity (TRIP) assisted HEA with composition Fe 50 Mn 30 Co 10 Cr 10 (at.%) was severely deformed by FSP and evaluated for its microstructure-mechanical property relationship. The FSP-engineered microstructure of the TRIP HEA exhibited a substantially smaller grain size, and optimized fractions of face-centered cubic (f.c.c., γ) and hexagonal close-packed (h.c.p., ε) phases, as compared to the as-homogenized reference material. This results in synergistic strengthening via TRIP, grain boundary strengthening, and effective strain partitioning between the γ and ε phases during deformation, thus leading to enhanced strength and ductility of the TRIP-assisted dual-phase HEA engineered via FSP.

Marine litter has been a serious and growing problem for some decades now. Yet, there is still much speculation among researchers, policy makers and planners about how to tackle marine litter from land-based sources. This paper provides insights into approaches for managing marine litter by reporting and analyzing survey results of litter dispersal and makeup from three areas along an Arab-Israeli coastal town in view of other recent studies conducted around the Mediterranean Sea. Based on our results and analysis, we posit that bathing beach activities should be a high priority for waste managers as a point of intervention and beach-goers must be encouraged to take a more active role in keeping beaches clean. Further, plastic fragments on the beach should be targeted as a first priority for prevention (and cleanup) of marine litter with plastic bottle caps being a high priority to be targeted among plastics. More survey research is needed on non-plastic litter composition for which amounts and geographic dispersal in the region vary greatly from place to place along Mediterranean shores. In general, findings of this study lead us to recommend exploring persuasive beach trash can design coupled with greater enforcement for short term waste management intervention while considering the local socio-economic and institutional context further for long-term efforts., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Misconceptions, or alternative conceptions, are incorrect understandings that students have incorporated into their prior knowledge. The goal of this study was the identification of misconceptions in microbiology held by undergraduate students upon entry into an introductory, general microbiology course. This work was the first step in developing a microbiology concept inventory based on the American Society for Microbiology's Recommended Curriculum Guidelines for Undergraduate Microbiology. Responses to true/false (T/F) questions accompanied by written explanations by undergraduate students at a diverse set of institutions were used to reveal misconceptions for fundamental microbiology concepts. These data were analyzed to identify the most difficult core concepts, misalignment between explanations and answer choices, and the most common misconceptions for each core concept. From across the core concepts, nineteen misconception themes found in at least 5% of the coded answers for a given question were identified. The top five misconceptions, with coded responses ranging from 19% to 43% of the explanations, are described, along with suggested classroom interventions. Identification of student misconceptions in microbiology provides a foundation upon which to understand students' prior knowledge and to design appropriate tools for improving instruction in microbiology.

If we are to teach effectively, tools are needed to measure student learning. A widely used method for quickly measuring student understanding of core concepts in a discipline is the concept inventory (CI). Using the American Society for Microbiology Curriculum Guidelines (ASMCG) for microbiology, faculty from 11 academic institutions created and validated a new microbiology concept inventory (MCI). The MCI was developed in three phases. In phase one, learning outcomes and fundamental statements from the ASMCG were used to create T/F questions coupled with open responses. In phase two, the 743 responses to MCI 1.0 were examined to find the most common misconceptions, which were used to create distractors for multiple-choice questions. MCI 2.0 was then administered to 1,043 students. The responses of these students were used to create MCI 3.0, a 23-question CI that measures students' understanding of all 27 fundamental statements. MCI 3.0 was found to be reliable, with a Cronbach's alpha score of 0.705 and Ferguson's delta of 0.97. Test item analysis demonstrated good validity and discriminatory power as judged by item difficulty, item discrimination, and point-biserial correlation coefficient. Comparison of pre- and posttest scores showed that microbiology students at 10 institutions showed an increase in understanding of concepts after instruction, except for questions probing metabolism (average normalized learning gain was 0.15). The MCI will enable quantitative analysis of student learning gains in understanding microbiology, help to identify misconceptions, and point toward areas where efforts should be made to develop teaching approaches to overcome them.

Understanding the mental constructs underlying people's social responses, decisions and behaviors is crucial to defining the governance challenges faced in dealing with marine anthropogenic litter. Using interactive governance theory, this study provides qualitative insights into how a small group of Arab-Israeli artisanal fishermen perceive marine litter and its impact (system to be governed) in the context of the socio-institutional structures (governing system) which manage waste and aim to protect the surrounding environment. It demonstrates that, until the relationships between local people and the various governing institutions are transformed, there is little hope for citizen cooperation in reducing marine litter long-term in the case-study site. More generally, underlying narratives and politics playing out at a local level need to be understood in order to identify which interventions are likely to be effective and which are not. An intervention checklist to assess the potential effectiveness of a marine litter intervention is proposed., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: Periplasmically localized copper-zinc co-factored superoxide dismutase (SodC) enzymes have been identified in a wide range of Gram-negative bacteria and are proposed to protect bacteria from exogenously produced toxic oxygen radicals, which indicates the potential significance of a Coxiella burnetii SodC., Results: Assays for SOD activity demonstrated that the cloned C. burnetii insert codes for a SOD that was active over a wide range of pH and inhibitable with 5 mM H2O2 and 1 mM sodium diethyldithiocarbamate, a characteristic of Cu/ZnSODs that distinguishes them from Fe or Mn SODs. The sodC was expressed by C. burnetii, has a molecular weight of approximately 18 kDa, which is consistent with the predicted molecular weight, and localized towards the periphery of C. burnetii. Over expression of the C. burnetii sodC in an E. coli sodC mutant restored resistance to H2O2 killing to wild type levels., Conclusions: We have demonstrated that C. burnetii does express a Cu/ZnSOD that is functional at low pH, appears to be excreted, and was able to restore H2O2 resistance in an E. coli sodC mutant. Taken together, these results indicate that the C. burnetii Cu/ZnSOD is a potentially important virulence factor.

Host control of Coxiella burnetii infections is believed to be mediated primarily by activated monocytes/macrophages. The activation of macrophages by cytokines leads to the production of reactive oxygen intermediates (ROI) and reactive nitrogen intermediates (RNI) that have potent antimicrobial activities. The contributions of ROI and RNI to the inhibition of C. burnetii replication were examined in vitro by the use of murine macrophage-like cell lines and primary mouse macrophages. A gamma interferon (IFN-gamma) treatment of infected cell lines and primary macrophages resulted in an increased production of nitric oxide (NO) and hydrogen peroxide (H2O2) and a significant inhibition of C. burnetii replication. The inhibition of replication was reversed in the murine cell line J774.16 upon the addition of either the inducible nitric oxide synthase (iNOS) inhibitor NG-monomethyl-L-arginine (NGMMLA) or the H2O2 scavenger catalase. IFN-gamma-treated primary macrophages from iNOS-/- and p47phox-/- mice significantly inhibited replication but were less efficient at controlling infection than IFN-gamma-treated wild-type macrophages. To investigate the contributions of ROI and RNI to resistance to infection, we performed in vivo studies, using C57BL/6 wild-type mice and knockout mice lacking iNOS or p47phox. Both iNOS-/- and p47phox-/- mice were attenuated in the ability to control C. burnetii infection compared to wild-type mice. Together, these results strongly support a role for both RNI and ROI in the host control of C. burnetii infection.

Coxiella burnetii is an obligate intracellular bacterium. The inability to cultivate this organism on axenic medium has made calculation of infectious units challenging and prevents the use of conventional antibiotic susceptibility assays. A rapid and reliable real-time PCR assay was developed to quantify C. burnetii cells from J774.16 mouse macrophage cells and was applied to antibiotic susceptibility testing of C. burnetii Nine Mile, phase I. For calculation of bacterial replication, real-time PCR performed equally as well as immunofluorescent-antibody (IFA) assay when J774.16 cells were infected with 10-fold serial dilutions of C. burnetii and was significantly (P < 0.05) more repeatable than IFA when 2-fold dilutions were used. Newly infected murine macrophage-like J774.16 cells were treated with 8 microg of chloramphenicol per ml, 4 microg of tetracycline per ml, 4 microg of rifampin per ml, 4 microg of ampicillin per ml, or 1 microg of ciprofloxacin per ml. After 6 days of treatment, tetracycline, rifampin, and ampicillin significantly (P < 0.01) inhibited the replication of C. burnetii, while chloramphenicol and ciprofloxacin did not. In general, these results are consistent with those from prior reports on the efficacy of these antibiotics against C. burnetii Nine Mile, phase I, and indicate that a real-time PCR-based assay is an appropriate alternative to the present methodology for evaluation of the antibiotic susceptibilities of C. burnetii.

Ground pork patties were inoculated separately with 10(9) CFU/g each of three strains of Listeria monocytogenes obtained from the National Animal Disease Center (NADC). Inoculated patties were packaged under vacuum and treated at 414 megapascals (60,000 lb/in2) for up to 60 min by high hydrostatic pressure (HHP). Survivors were determined by surface plating onto modified Oxford agar and trypticase soy agar with yeast extract, as well as by the most probable number method using Listeria enrichment broth. Average D values ranged from 1.89 to 4.17 min, depending on the strain, with the most virulent strain (reported by the NADC) having the highest D value. We tested the usefulness of applying a mild heat treatment at 50 degrees C, simultaneously with HHP, to lower these values. Average D values ranged from 0.37 to 0.63 min, depending on the strain. Thus, a 10-log10 reduction could be achieved even in the most pressure-resistant strain of L. monocytogenes by a 6-min application of heat and HHP. Shelf life studies were also conducted, with spoilage levels reached after 5 days of storage at 4 degrees C for controls versus 28 days for treated samples. Sensory evaluation of uninoculated grilled patties showed that panelists could not distinguish between those treated by heat and HHP and untreated controls (P<0.05). Thus, treatment by HHP in combination with mild heating can be used successfully to produce safer, longer-lasting fresh pork without affecting quality.

Irradiation of ground beef patties inoculated with the organism Escherichia coli O157:H7 was performed either by gamma rays from a cobalt 60 source or by electron beam generated by a linear accelerator. Patties were packaged in one of the following materials: nylon/polyethylene bags, Saran/polyester/polyethylene bags (PM2), or Saran overwrap with a Styrofoam tray inside. Bags were sealed in air or under vacuum and were irradiated at either 5 or -15 degrees C. Average D10 values (dose required to inactivate 90% of a microbial population) ranged from 0.27 to 0.63 kGy, depending on the conditions. Overall, higher D10 values (P<0.0001) were obtained upon irradiation at -15 degrees C as compared with 5 degrees C. Cells inoculated in samples packaged in PM2 had the highest D10 values, but only if irradiated by electron beam at -15 degrees C (P<0.001). Since PM2 had the lowest oxygen permeability rate and since the temperature was too low for radicals to migrate easily, these conditions may have minimized the effect of oxygen- and water-derived radicals on microbial survival. Irradiation by gamma rays resulted in higher D10 values (P<0.047) than irradiation by electron beam, with the highest values being observed at -15 degrees C. Differences may be attributed to dose rate (1.0 kGy/h for gamma, 17 kGy/min for electron beam) since it is possible that, at low dose rates, microbial enzymes may have more time to repair damage to the cell due to irradiation, resulting in higher D10 values.

Objective: To determine systemic and mucosal antibody responses in calves to Pasteurella haemolytica 1:A and to 2 major outer membrane proteins (OMP) and 1 major iron-regulated OMP of P haemolytica 1:A., Animals: 23 crossbred calves., Procedure: 2 experiments were performed in the first experiment, 6 calves were vaccinated and challenge exposed intranasally with an aerosol of P haemolytica 1:A and 6 calves were only challenge exposed. In the second experiment, 8 calves were vaccinated in the area of the tracheal bifurcation with an aerosol of P haemolytica 1:A and 3 calves were used as controls. Serum, nasal secretions, and bronchoalveolar lavage (BAL) samples were collected, and IgG1, IgG2, IgA, and IgM titers were determined. Nasal secretions and BAL samples were also submitted for bacterial culture., Results: Serum antibody responses in the 2 groups were similar. Antibody titers in nasal secretions and BAL samples increased in calves vaccinated intranasally. In calves vaccinated in the area of the tracheal bifurcation, antibody titers increased in BAL samples but not in nasal secretions. Antibody responses did not correlate with results of bacterial culture., Conclusions: Results indicated that intranasal administration of P haemolytica 1:A may be a better method for stimulating protective immune responses in the upper portion of the respiratory tract than lung administration. The single dilution ELISA provided a reliable and economical method for determining antibody titers.

A recent case in California raises legitimate concern about the risks of a lawsuit arising out of a routine physical examination. This ruling has an ominous portent for many physicians who either are not current or are not comfortable with the available testing procedures for screening asymptomatic patients for silent myocardial ischemia.

A retrospective study of clinical case records was conducted at the health centre of a rural central Australian Aboriginal community to determine the frequency of acute rheumatic fever and of rheumatic heart disease between 1978 and 1987. The case records of 976 residents over 5 years of age were examined for evidence of the clinical indicators of acute rheumatic fever or rheumatic heart disease; together they contributed 8015 person-years of study. During the 10-year study period, 18 patients developed acute rheumatic fever and 12 patients had rheumatic heart disease. The annual incidence of acute rheumatic fever (first and recurrent attacks) for children aged 5-14 years was 815 per 100,000 person-years. For the residents aged 5 years and over, the point prevalence for rheumatic heart disease at the end of 1987 was between 7.9 and 12.3 per 1000 persons, according to health clinic records and the official population census, respectively. These rates are similar to those reported for Third World countries. Preventive measures must include efforts by health professionals to help to alleviate the adverse living conditions in Aboriginal communities.

An athletic young female developed gradual onset of pain in the right leg. Plain radiographs demonstrated solid periosteal reaction in the tibia compatible with stress fracture. She stopped sport activities but her pain continued. Follow-up radiographs of the tibia revealed changes suspicious for osteoid osteoma. Computed tomography (CT) scan demonstrated periosteal reaction, but in addition, lucent fracture lines in the tibial cortex were evident. CT obviated the need for more invasive diagnostic procedures in this patient. In selected cases CT may be useful to confirm the diagnosis of stress fracture when plain radiographic or routine tomographic studies are not diagnostic.

Large renal parenchymal masses are a rare manifestation of metastatic malignant melanoma. We report the second and third such cases to be noted on excretory urography.

The indications for knee arthrography in children consist of: suspected internal derangement; osteochondritis dissecans; Blount's disease; popliteal cysts; loose bodies; synovial tumors; and miscellaneous abnormalities including unexplained knee pain.

Computed tomography (CT) is an ideal method for the imaging of the psoas muscle. The authors present 13 cases of patients with psoas abnormalities diagnosed by CT. The CT features of the different pathologic entities and comparison of CT with other imaging modalities are discussed.

Six patients with bifid blind-ending ureter diagnosed at excretory urography are presented. In four of six patients the blind ureter was an incidental discovery. All had a characteristic appearance on urography consisting of an elongated contrast-filled tubular structure which usually terminated in a bulbous proximal tip. Demonstration of the rounded tip at excretory urography is important as it indicates the entire blind ureter has been opacified, obviating the need for retrograde pyelography.

A booklet, "Assessment of Maternal Nutrition," has been published by the American College of Obstetricians and Gynecologists in cooperation with The American Dietetic Association as a useful guide for physicians, nurses, dietitians, and nutritionists. Nutritional risks during pregnancy are clearly outlined. Clinical, dietary, and biochemical factors, as well as medical, obstetric, and social factors, are delineated as components of nutritional assessment. An A.D.A. Liaison Committee had major responsibility for the development of the "Eating Habits Questionnaire," a tool to screen dietary intake for major deficits and excesses, which is included in the booklet. It should be useful also as a starting point for nutrition education. Additional evaluation of the use and reliability of the screening tool is recommended.

Nutrient intake of a group of 22 young, mainly black, low-income pregnant women was evaluated by use of data resulting from laboratory analysis of foods prepared and consumed in the home over a 24-hour period. Magnesium, zinc, and folacin were the nutrients least well supplied in the foods consumed. Analyzed values for daily intake of the three were below 50% of the RDAs. Mean energy intake was considerably lower than recommended allowances, even though mean gain in weight was somewhat greater than that recommended for normal pregnancy, a finding like that of other investigators. The wide range in daily intake of energy and various nutrients among subjects is comparable with that found in a number of other studies, which showed that many individuals have marked deviations in intake from day to day. Analyzed diets also were examined in terms of nutrient density. Mean nutrient density for protein, calcium, phosphorus, vitamin A, thiamin, riboflavin, niacin, and ascorbic acid compared favorably with that of the RDAs, in contrast with the poor nutrient density for zinc, magnesium, and folacin. Laboratory analysis of the diets had the advantage of providing information about nutrient content of foods as prepared and consumed in the home. The analysis had particular advantage in the evaluation of content of zinc, magnesium, and folacin, as data for the three nutrients in food composition tables are limited.

Following 24-hour fasting and fluid deprivation, sequential changes in CT numbers of the canine kidney were determined in 4 dogs, each of whom received, at intervals, IV sodium diatrizoate, metrizamide, iopamidol, and sodium ioxaglate at a dose of 500 mgI/kg body weight. The urinary bladder was catheterized for baseline determination of urine osmolality and, subsequently, urine volume and CT number, CT number of the bladder urine from 0 to 10 minutes and from 10 to 20 minutes post-injection was obtained by scanning known dilutions of urine in vitro. Peak renal cortical enhancement occurred within 2 minutes of bolus injection and was not dependent on the chemical make-up of the contrast agent. Peak medullary enhancement occurred within 3 minutes of bolus injection. Peak medulla CT number following sodium diatrizoate was significantly less than that following metrizamide (P less than 0.025) or iopamidol (P less than 0.01). Peak medulla CT number was significantly less following sodium diatrizoate (P less than 0.01), metrizamide (P less than 0.01) and iopamidol (P less than 0.05) than following sodium ioxaglate. Urine iodine concentrations followed a similar pattern, with significant differences as follows: sodium diatrizoate less than metrizamide = iopamidol less than sodium ioxaglate. It was concluded that the investigational agents metrizamide, iopamidol, and sodium ioxaglate have theoretical advantage for excretory urography. Differences in renal handling of these agents are detectable, with CT scanning as differences in renal medullary enhancement and urine iodine concentration.

Using a 30-second computed tomography (CT) scanner, the sequential changes in CT numbers of the kidney were determined in three healthy dogs after intravenous administration of sodium and meglumine diatrizoate and iothalamate. For all contrast media, the mean CT number of the cortex was greatest within 2 minutes of rapid intravenous administration. At doses comparable to those used clinically, a linear relationship was demonstrated between the amount of iodine administered (in mg/kg body weight) and the corrected peak mean CT number of the cortex, such that doubling the amount of iodine caused the corrected peak mean CT number of the cortex to approximately double. Following the peak, the mean CT number of the cortex gradually declined. For all contrast media, the corrected mean CT number to corrected peak mean CT number ratios at 5, 10 and 20 minutes were 58 +/- 3%, 39 +/- 3%, and 28 +/- 5% respectively. Our data suggest that rapid-sequence CT may be a valuable tool for evaluating the physiology of renal contrast media excretion.

A calyx which fails completely to opacify on excretory urography (phantom calyx) is often the harbinger of serious underlying renal disease. Causes of a phantom calyx include tuberculosis, tumor, calculus, ischemia, trauma, and congenital anomaly. The pathologic basis for the radiographic findings in each of these entities is described and an overall approach to diagnosis is set forth.

The clinical, plain skull radiographic, brain scan, and CT findings of four patients with cerebral hemiatrophy are described. CT scanning is the most innocuous and most sensitive diagnostic method available to confirm the clinical diagnosis when plain skull radiographic changes are not confirmatory.

Nutrient composition of diets of low-income pregnant women was determined by laboratory analysis and by calculation from food tables. Twenty-two diet composites, each representing a subject's 24-hour intake, were so evaluated. Findings from use of the two methods were compared. Mean analyzed and calculated values compared favorably for food energy, protein, fat, carbohydrate, potassium, magnesium, and zinc, although large differences in values as determined by the two methods were found in some single diet composites. Analyzed values compared less favorably with calculated values for calcium, phosphorus, iron, sodium, and the six vitamins studied.