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Insertion of a nitrogen atom modifies the electronic structures and photochemistry of polycyclic aromatic hydrocarbons by introducing nπ* states into the molecules. To better understand the electronic structures of isolated polycyclic aromatic nitrogen-containing hydrocarbons (PANHs) and their dimers as well as the influence of the position of the nitrogen atom in the molecule, we investigate three different azaphenanthrenes, benzo[f]quinoline, benzo[h]quinoline, and phenanthridine, in a joint experimental and computational study. Experimentally, resonance-enhanced multiphoton ionization (REMPI) spectroscopy is applied to characterize the excited electronic states. The REMPI spectra of the azaphenanthrene monomers have a rather similar appearance, with origins between 3.645 and 3.670 eV for the 1ππ* ← S0 transition. In contrast to the phenanthrene parent, 2ππ* ← S0 is broad and unstructured even at the band origin. The experiments are accompanied by density functional theory computation, and vibrationally resolved spectra are simulated using a time-independent approach. The differences between phenanthrene and the azaphenanthrenes are assigned to perturbations due to the low-lying 1(nπ*) state, which accelerates nonradiative deactivation. For the dimers, it is found that two π-stacked isomers with two electronic transitions each contribute to the electronic spectrum, leading to overlapping bands that are difficult to assign.

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INTRODUCTION: The sonographic findings of the udder parenchyma and udder lymph nodes in 30 lactating sheep after experimental infection with Mycoplasma agalactiae are described. The objective of the study was to describe infection related changes in the udder parenchyma and udder lymph nodes using physical, sonographic, and histological examination and to detect associations between sonographic and histological changes of the tissues. Animals were intramammarily infected with different mutant cocktails and the wild type PG2. One group served as a negative control. A 15 MHz linear transducer (Esaote MyLab 30 CV, Esaote, Florence, Italy) was used for sonographic examinations. Compared with the uninfected control group with homogeneously granular parenchyma, the udder lymph nodes were larger and the udder parenchyma was more inhomogeneous and partially hyperechoic. The corresponding histological findings in infected mammary glands comprised proliferation of interstitial connective tissue, non-purulent interstitial mastitis, and purulent galactophoritis. The infected udder lymph nodes showed reactive hyperplasia. The findings obtained in this study may improve the diagnosis of Mycoplasma mastitis in sheep.

INTRODUCTION: Les constatations échographiques sur le parenchyme de la mamelle et des ganglions lymphatiques de la mamelle chez 30 brebis en lactation après une infection expérimentale avec Mycoplasma agalactiae sont décrits. L'objectif de l'étude était de décrire les modifications liées à l'infection dans le parenchyme mammaire et les ganglions lymphatiques de la mamelle à l'aide d'un examen physique, échographique et histologique et de détecter les associations entre les altérations échographiques et histologiques des tissus. Les animaux ont été infectés par voie intramammaire avec différents cocktails de mutants et le type sauvage PG2. Un groupe a servi de contrôle négatif. Une sonde linéaire de 15 MHz (Esaote MyLab 30 CV, Esaote, Florence, Italie) a été utilisé pour les examens échographiques. Comparativement au groupe témoin non infecté avec un parenchyme granulaire homogène, les ganglions lymphatiques de la mamelle étaient plus gros et le parenchyme de la mamelle était plus inhomogène et partiellement hyperéchogène. Les résultats histologiques correspondants dans les glandes mammaires infectées comprenaient une prolifération de tissu conjonctif interstitiel, une mammite interstitielle non purulente et une galactophorite purulente. Les ganglions lymphatiques de la mamelle infectée présentaient une hyperplasie réactive. Les résultats obtenus dans cette étude peuvent améliorer le diagnostic de la mammite à Mycoplasma chez le mouton.

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OBJECTIVE: This 12-month randomized, non-inferiority clinical trial sought to determine the impact of consuming soy protein as part of an energy-restricted, high-protein diet on weight loss, body composition and cardiometabolic health. METHODS: Seventy-one adults (58 female) with overweight or obesity (body mass index: 32.9 ± 3.6 kg m-2) were randomly assigned to consume three servings of soy (S) or non-soy (NS) protein foods per day for 12 months. All participants completed a group-based behavioural weight loss program lasting 4 months (M4), and follow-up assessments were completed at month 12 (M12). RESULTS: Body weight was reduced in both groups at M4 (S: -7.0% ± 5.2%, NS: -7.1% ± 5.7%) and M12 (S: 3.6% ± 5.1%, NS: -4.8% ± 7.3%). Body weight reductions (mean difference [90% confidence interval]) were not different between S and NS at either time point (M4: -0.16% [-1.4, 3.6], P = 0.90; M12: 1.1% [-1.4, 3.6], P = 0.44). Differences in body fat mass loss were not different between S and NS at M4 (0.29 ± 0.84 kg, P = 0.73) or M12 (0.78 ± 1.5 kg, P = 0.59). Weight loss-induced improvements in cholesterol, triglycerides and blood pressure did not differ between S and NS. CONCLUSION: These results indicate that soy-based protein foods can be effectively incorporated into an energy-restricted, high-protein diet for improving body weight, body composition and cardiometabolic health.

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Diarrhoea is a condition with tremendous impact on calf health. Infectious agents play a dominant role; however, non-infective factors may also contribute to pathogenesis of diarrhoea. One factor, the abomasal emptying rate, is mainly influenced by the composition of feed. The aim of the study was to assess the influence of different protein sources in milk replacers on abomasal emptying rate and clinical parameters. The effect of increasing age of the calves on abomasal emptying was also evaluated. The study compared abomasal emptying rates and clinical parameters in calves, which were fed either milk replacer containing only whey protein or one which partially contained wheat protein. Abomasal emptying rate was estimated by ultrasonography. Ten calves were used in the study over 18 days, and each calf was fed 3 periods of 3 days length using different milk replacers in an alternating crossover design. The abomasum was emptied significantly faster when the wheat protein containing milk replacer was fed (half-emptying time wheat protein 49.1 ± 4.1 min, half-emptying time milk protein 59.1 ± 7.4 min); however, clinical parameters and weight gain did not differ between the feeding regimes. Age did not significantly influence abomasal emptying rate. As milk replacers containing wheat proteins increased abomasal emptying rate, they may have a higher potential to initiate diarrhoea, especially if high volumes are fed. Thus, the feeding regimes are likely to be even more important when such milk replacers are used.

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A mouse model resembling Streptococcus equi subspecies equi infection in the horse, strangles, was used to assess the protective effect of vaccination with selected recombinant proteins from S. equi subsp. equi. After challenge the infection was monitored by weight loss and by nasal colonisation with S. equi subsp. equi. Vaccination with a collagen-binding protein (CNE) and a collagen-like protein (SclC) resulted in protective antibodies, whereas a novel fibronectin-binding protein (FNEB) did not. Co-administration of CNE with EAG, a poorly immunogenic alpha2-macroglobulin-, albumin- and immunoglobulin G-binding protein, resulted in a significant synergistic effect and enhanced the protective immune response against EAG.

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Fifty-two cattle with diseases of the udder were evaluated by means of sonography between 2000 and 2004. The udders were examined with 3.5 and 5.0 MHz convex transducers and 7.5 and 13.0 MHz linear transducers. Bacteriological examinations were also performed on individual quarter samples. Ultrasonography gave additional information on the status of the udder and showed findings specific for some causal agents, e.g., Enterobacteriaceae and Arcanobacterium pyogenes as well as udder haematomas. All forms of mastitis required bacteriological confirmation for the final diagnosis.

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The pleura and lungs were evaluated by means of sonography in 55 bovine patients with diseases of the thoracic cavity. For these ultrasound examinations, a range of transducers was used. As the lung surface was most often involved in cases of pulmonary disease, it was possible to detect ultrasonographically bronchopneumonia, consolidation, pleural effusion, pulmonary emphysema and pleuritis. Determination of the amount of lung tissue affected provided prognostic information. It was not possible to visualise lesions located deeper within the lungs where peripheral tissue was not affected. A diagnosis of thoracic disease was made on the basis of clinical and ultrasonographic findings and confirmed in 33 cases at necropsy.

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In total records of 363 East Friesian breed of sheep and 15 Lacaunes from 15 flocks located in Lower Austria, Upper Austria and Styria were available to investigate the influences on milk urea content. In one flock different groups of ewes were fed with low, medium and high amounts of energy and protein, but constant protein and energy ratio. The milk urea levels exhibited to statistically significant differences but the tendency of the feeding effect could be confirmed. Additional parameters influencing the urea content of milk of ewes are: herd specific factors, stage of lactation, mastitis, preservation and different analytical methods. The content of urea in milk is not suitable for assessment of the energy/protein-ratio of ewes with mastitis problems. Due to the special composition of sheep milk it is important to take account of the analytical method for determination of urea. Thus milk urea of one flock should be evaluated but not of individual sheep. In spite of these influence factors the determination of milk urea is a valuable tool for assessment of the energy and protein intake.

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Extracellular adherence protein Eap secreted from Staphylococcus aureus was previously found to enhance the adherence of S. aureus to eukaryotic cells. This enhancement effect is due to the ability of Eap to rebind to S. aureus and to bind to eukaryotic cells and several plasma and matrix proteins. In this study we defined one potential binding target for Eap on the surface of S. aureus, a surface-located neutral phosphatase. This phosphatase lacks an LPXTG region, but around 80% is retained on the cell surface. The soluble phosphatase can form a complex with Eap at a nonrandom molar ratio, and phosphatase activity is retained. The phosphatase can also bind to fibronectin. The cell surface-located portion presumably contributes to adherence of S. aureus to fibronectin.

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Efb (previously Fib) is a fibrinogen-binding protein secreted by Staphylococcus aureus. It has previously been shown that it plays a role in a wound infection model in the rat and that antibodies against Efb reduce the number of recovered bacteria from the mammary glands in a mouse mastitis model. Efb binds to the alpha-chain of fibrinogen and does not participate in bacterial adherence to fibrinogen. The binding of Efb to fibrinogen is divalent, with one binding site within the two repeat regions in Efb at the N terminus and one binding site at the C terminus. The divalent binding nature leads to precipitation of Efb-fibrinogen complex when the proteins are added to each other at a 1:1 molar ratio. The interaction between Efb and fibrinogen is strongly enhanced by Ca2+ or Zn2+ but not by Mg2.

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In vitro collagen binding of 216 Staphylococcus aureus isolates from patients with various diagnoses was studied. Polymerase chain reaction was used to examine these isolates regarding the existence of the corresponding cna gene. Distribution of capsular polysaccharide (CP) types was examined. Fifty-six (57%) of 99 S. aureus isolates from patients with endocarditis or bacteremic bone or joint infection were cna-positive compared with 65 (56%) of 117 isolates from bacteremic patients without signs of bone or joint infection (P = .99). There was a good correlation between in vitro collagen binding and presence of the cna gene. These data suggest that collagen binding is not a prerequisite for the development of endocarditis, osteomyelitis, or septic arthritis. There was no significant difference in the distribution of CP types among various patient groups, although there was a strong association between CP type 8 and the existence of the cna gene.

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OBJECTIVES: Syphilis in the United States is focally distributed, with high incidence rates in the South and in metropolitan areas nationwide. In this study an ecological analysis, using the county as the unit of analysis, was performed to generate hypotheses about community-level determinants of syphilis rates. METHODS: Bivariate rank correlations and multivariate, backward stepwise elimination linear regressions were performed. Mean annual incidence of primary- and secondary-stage syphilis in a county was the dependent variable, and county sociodemographic characteristics (from census data) were the independent variables. RESULTS: In the multivariate regression model, sociodemographic characteristics accounted for 71% of the variation in syphilis rates among counties. With other factors accounted for, the most highly correlated characteristics were percentage non-Hispanic Black population, county location in the South, percentage of the population that was urban, percentage Hispanic population, and percentage of births to women younger than 20 years. CONCLUSIONS: Most of the variation in syphilis rates among counties is accounted for by sociodemographic characteristics. Identification and remediation of modifiable health determinants for which these factors are markers are needed to improve the health status of these populations.

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Streptococcus mutans P1 antigen functions as an adhesion factor for binding to salivary pellicle on tooth surfaces. It induces increased antibody titres in patients with Strep. mutans endocarditis. A mutant of Strep. mutans deficient in the function of the gene (spa P) encoding the surface antigen P1, and its isogenic parental strain, were used in a rat endocarditis experiment. Absence of P1 did not decrease adhesion to vegetations determined l h after intravenous infection. The number of bacteria recovered from valvular vegetations after 48 h from animals with manifest endocarditis did not differ between the strains. Consequently, the Pl antigen appears to be unimportant both for adhesion and virulence in endocarditis caused by Strep. mutans.

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BACKGROUND AND OBJECTIVES: The distribution and trends of syphilis are influenced by biologic factors, sexual behaviors, biomedical technology, availability of and access to health care, public health efforts, changes in population dynamics, and sociocultural factors. The objective of this article is to review the epidemiology of syphilis in the United States during the period 1941-1993 in the context of some of these factors. STUDY DESIGN: Surveillance data on cases of syphilis and congenital syphilis reported by state and city health departments to the Centers for Disease Control and Prevention were analyzed to show distribution and trends by geographic location, racial and ethnic groups, gender, and age. RESULTS: Historically, syphilis was distributed widely throughout the country and declined rapidly after the introduction of penicillin therapy and broad-based public health programs, attaining its lowest levels in the 1950s. However, in recent years, the disease has returned and become focused in the southern region and in urban areas outside that region. Rates of syphilis have remained highest in black Americans, and the most recent national epidemic of syphilis primarily involved them. Rates in white men were at intermediate levels during the early 1980s but have declined to low rates in the 1990s, possibly because of changes in behavior in response to the AIDS epidemic. Rates in white women and other racial and ethnic groups have remained low throughout the 1980s and 1990s. CONCLUSIONS: Syphilis remains a significant problem in the United States, and its epidemiology is influenced by a complex combination of factors. To prevent and control syphilis effectively, public health practitioners must understand these factors and design programs and interventions that address the disease in the context of these factors.

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The potential energy surface of the neutral form ofγ-aminobutyric acid was investigated by means of ab-initio 4-31 G SCF calculations. Geometries, energies, and selected wave numbers of all 62 symmetry unique local minima are reported. Intramolecular interactions and all reactions, which involve the intramolecular hydrogen bond, are discussed and compared with those present in the homologuesß-alanine and glycine.

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Concurrent abortion and sterilization are preferred by many women to avoid a second hospitalization, operation, and, in some instances, general anesthesia. Several authors have shown concern, however, that the two procedures carry a higher risk of morbidity when performed concurrently versus separately. To determine whether the concurrent performance of sterilization and induced abortion is as safe as the two procedures performed separately, we selected women undergoing these procedures from two separate multicenter, prospective, national United States studies: the Joint Program for the Study of Abortion and the Collaborative Review of Sterilization. Using standard definitions of major morbidity, we calculated the crude rate of one or more major complications to be 0.9% for the abortion-only group, 1.7% for the group concurrent abortion and tubal sterilization. Thus our data suggest that performing concurrent abortion and sterilization is as safe as performing those procedures separately.

PIP: Concurrent abortion and sterilization are preferred by many women to avoid a 2nd hospitalization, operation, and, in some instances, general anesthesia. Several authors have shown concern, however, that the 2 procedures carry a higher risk of morbidity when performed concurrently versus separately. To determine whether the concurrent performance of sterilization and induced abortion is as safe as the 2 procedures performed separately, women undergoing these procedures from 2 separate multicenter, prospective, national US studies were selected: the Joint Program fro the Study of Abortion and the Collaborative Review of Sterilization. Using standard definitions of major morbidity, the crude rate of 1 or more major complications was calculated to be 0.9% for the abortion only group, 1.7% for the group concurrent abortion and tubal sterilization. Thus the authors' data suggest that performing concurrent abortion and sterilization is as safe as performing those procedures separately.

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To identify risk factors for febrile complications after suction curettage abortion, we analyzed the data of 26,332 women who underwent suction curettage abortion at five participating centers in the Joint Program for the Study of Abortion, Part III, from 1975 to 1978. We defined febrile morbidity as an oral temperature of greater than or equal to 38 degrees C for 2 days or longer. The febrile morbidity rate was 0.34 per 100 abortions. We performed a multivariate analysis using a linear logistic regression model. Prophylactic antibiotics proved to be the most protective factor, reducing the rate of febrile complications to about one third that of women who received no prophylactic antibiotics (relative risk 0.36; 95% confidence interval 0.18 to 0.70). Patients who had had one or more previous births also had a significantly lower risk of febrile morbidity (relative risk 0.54; 95% confidence interval 0.33 to 0.88). Other factors did not significantly affect the febrile complication rate.

PIP: To identify risk factors for febrile complications after suction curettage abortion, the authors analyzed the data of 26,332 women who underwent suction curettage abortion at 5 participating centers in the Joint Program for the Study of Abortion, Part III, from 1975-76. Febrile morbidity was defined as an oral temperature of greater than 38 degrees Centigrade for 2 days or longer. The febrile morbidity rate was 0.34/100 abortions. A multivariate analysis was performed using a linear logistic regression model. Prophylactic antibiotics proved to be the most protective factor, reducing the rate of febrile complications to about 1/3 that of women who received no prophylactic antibiotics (relative risk 0.36; 95% confidence interval 0.18-0.70). Patients who had had 1 or more previous births also had a significantly lower risk of febrile morbidity (relative risk 0.54; 95% confidence interval 0.33-0.88). Other factors did not significantly affect the febrile complication rate.

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