Actinobacillus pleuropneumoniae in Thai Pig Herds. Prevalence of Serum Antibodies and Relation to Performance

The aim of the study was to investigate the prevalence of Actinobacillus pleuropneumoniae infections in market weight pigs in Thailand. ELISA systems employing purified lipopolysaccharide antigens were used to detect antibodies in 549 serum samples collected from pigs of 22 herds. Relevant cut-off values were established from three herds defined seronegative. Serum antibodies were detected to all serotypes except serotype 10. Almost 60% of the samples were seropositive to at least one serotype and 45% of the pigs were seropositive to more than one serotype. Antibodies to the cross-reacting serotypes 1, 9 or 11 were found in 29% of the pigs. Other common serotypes included the cross-reacting serotypes 3, 6 or 8 (26% seropositive pigs) and serotype 5a (also 26%). Antibodies to serotypes 2, 5b and 12 were low in prevalence (<10%). Three herds were regarded to be seronegative and six to have a low pathogen load with respect to the prevalence of seropositive pigs. The remaining 13 herds had a high incidence of pigs with antibodies to A. pleuropneumoniae, dominated by serotypes 1-9-11 and 5a (n = 6), serotypes 3-6-8, and 5a (n = 4) or 1-9-11, 3-6-8, 5a and 4-7 (n = 3). A low pathogen load with respect to A. pleuropneumoniae, as well as small herd size and age-segregated rearing, tended to improve the performance of growers.

Mechanisms of molecular manipulation with the scanning tunneling microscope at room temperature: chlorobenzene/si(111)-(7 x 7)

We report a systematic experimental investigation of the mechanism of desorption of chlorobenzene molecules from the Si(111)-(7 x 7) surface induced by the STM at room temperature. We measure the desorption probability as a function of both tunneling current and a wide range of sample bias voltages between -3 V and +4 V. The results exclude field desorption, thermally induced desorption, and mechanical tip-surface effects. They indicate that desorption is driven by the population of negative (or positive) ion resonances of the chemisorbed molecule by the tunneling electrons (or holes). Density functional calculations suggest that these resonant states are associated with the pi orbitals of the benzene ring.

Antiseptic wound ventilation with a gas diffuser: a new intraoperative method to prevent surgical wound infection?

Postoperative wound infections are often a result of peri-operative contamination by Staphylococcus aureus. With a new insufflation device, a gas diffuser, it has become possible to establish a local micro-environment of almost 100% carbon dioxide in an open surgical wound. The device enables ventilation of the wound with an antiseptic agent, which in gaseous form can be delivered as a low uniform dose to all parts of the wound. The use of carbon dioxide (CO2) as a carrier gas eliminates possible inflammability of an antiseptic agent and helps to concentrate it to the site of interest by gravity. Using the above delivery system we have demonstrated the antibacterial effect of gaseous ethanol on S. aureus inoculated on sterile filter disks and blood agar plates, respectively. Ethanol is a very potent antiseptic agent with known properties, which makes it suitable for testing the maximal decontamination level. On filter disks, CO2 carrying vapour from a 95% ethanol solution decreased the number of colony-forming units after 5 min of exposure (P=0.04), and killed all bacteria within 10-15 min (P<0.001). In the presence of organic material, i.e. on exposed blood agar plates, the colony size decreased with exposure time, and no colonies were detected after 60 min of exposure (P<0.001). Antiseptic gas derived from 70% ethanol solution was less effective than that from 95% ethanol (P<0.001). CO2 humidified with water did not have a significant effect on number or size of the colonies. Our findings suggest that intraoperative wound antisepsis with a gas mixture of CO2 and an antiseptic agent delivered with a gas diffuser, may be a simple method to reduce the risk of postoperative wound infection.

Distance dependence of the interaction between single atoms: gold dimers on NiAl(110)

The importance of substrate-mediated adsorbate-adsorbate interactions on electronic states has been demonstrated for Au dimers on NiAl(110) with a scanning tunneling microscope and density functional calculations. An unoccupied resonance observed in single Au atoms splits into a doublet in Au dimers. The energy splitting depends inversely on the distance between the two adatoms, revealing the relative importance of direct and substrate-mediated interactions. Spatially resolved conductance measurements of Au dimers reveal the symmetric and antisymmetric characters of the doublet states.

Arterial pulse wave velocity with tissue Doppler imaging

This paper describes a new noninvasive ultrasonic method for estimating pulse wave velocity (PWV), an important physical parameter for characterizing the elastic properties of the arterial walls. The method utilizes a relatively new color Doppler modality for measuring tissue motion (tissue Doppler imaging or TDI). In contrast to previously proposed methods, the TDI modality offers multiple recording sites along the artery that improve the PWV estimation considerably. The new PWV estimation method was evaluated through an in vitro setup consisting of an elastic vessel supplied with a pulsatile pump. The study concentrated on the effect of different system parameters controlling resolution, sensitivity and the amount of acquired data. It was shown that the system parameters have a significant effect on the PWV variance, whereas the PWV mean remains unchanged. It was also established that high temporal resolution is the most vital parameter for minimizing PWV variance. Finally, the new PWV estimation method was applied to a limited set of human carotid artery data sets, with good results.

Energy loss of atoms at metal surfaces due to electron-hole pair excitations: first-principles theory of "chemicurrents"

A method is presented for calculating electron-hole pair excitation due to an incident atom or molecule interacting with a metal surface. Energy loss is described using an ab initio approach that obtains a position-dependent friction coefficient for an adsorbate moving near a metal surface from a total energy pseudopotential calculation. A semiclassical forced oscillator model is constructed to describe excitation of the electron gas due to the incident molecule. This approach is applied to H and D atoms incident on a Cu(111) surface, and we obtain theoretical estimates of the "chemicurrents" measured by Nienhaus et al. [Phys. Rev. Lett. 82, 446 (1999)] for these atoms incident on the surface of a Schottky diode.

The reproducibility of a new dietary record routine in geriatric patients

BACKGROUND AND AIM

Malnutrition in nursing home residents is an important clinical and public health problem. Knowledge is lacking about the reproducibility of dietary recording in geriatric patients. Few studies have described water intake in this age group. The aim of this study was to test the reproducibility of a 7-day dietary record routine in a clinical setting.

METHODS

The dietary intake of 81 geriatric patients was recorded for two discrete periods of 7 consecutive days by the ward staff. The dietary record routine, which assessed both food and fluid intake, was based on standardized portion sizes and household measurements.

RESULTS

The mean daily energy intake during the first period was 7.07 MJ and 6.84 MJ during the second period, with a mean difference of 4%. Corresponding values and the mean difference for water intake from food and beverages were 1781 g, 1702 g and 4% respectively. Age, gender, diagnosis, length of stay, diets or ADL function did not influence the results. The correlation coefficient for fluid intake between the periods was 0.84 for women and 0.72 for men.

CONCLUSION

The 7-day dietary record routine seems to have a good reproducibility in assessing the intake of energy and fluids in geriatric patients.

Female alcoholism: differences between female alcoholics with and without a history of additional substance misuse

The purpose of the present study was to investigate personality traits and platelet monoamine oxidase (MAO) activity, as well as occurrence of personality disorder criteria, family characteristics, and criminal activity as related to misuse pattern in a sample of female in-patients with severe alcohol dependence. In accordance with theoretical assumptions and empirical findings of underlying neurobiological correlates of disinhibition in individuals with double or multiple misuse patterns, the female alcoholics were divided into subgroups with: (1) alcohol as their single drug of misuse (ALC; n = 16); (2) a history of additional substance misuse (ALC-DRUG; n = 11). Platelet MAO activity of the female subgroups was studied in comparison to a control group of non-clinical female subjects. Marked differences were obtained between the two subgroups. The ALC-DRUG females scored significantly higher with regard to Karolinska Scales of Personality (KSP) impulsiveness, anxiety-related traits, and non-conformity, displayed higher frequency of depression in first degree relatives, were more frequently involved in criminal activity, and more frequently diagnosed for any personality disorder according to DSM-IV, axis II. Finally, the ALC-DRUG females displayed significantly lower platelet MAO activity than controls. In conclusion, the results support the usefulness of a classification of severe alcoholic female subjects according to having/not having a history of additional substance misuse. The present female alcoholics with a history of additional misuse formed a group of individuals fulfilling the criteria similar for male type 2 alcoholism.

Comparison of electron paramagnetic resonance methods to determine distances between spin labels on human carbonic anhydrase II

Four doubly spin-labeled variants of human carbonic anhydrase II and corresponding singly labeled variants were prepared by site-directed spin labeling. The distances between the spin labels were obtained from continuous-wave electron paramagnetic resonance spectra by analysis of the relative intensity of the half-field transition, Fourier deconvolution of line-shape broadening, and computer simulation of line-shape changes. Distances also were determined by four-pulse double electron-electron resonance. For each variant, at least two methods were applicable and reasonable agreement between methods was obtained. Distances ranged from 7 to 24 A. The doubly spin-labeled samples contained some singly labeled protein due to incomplete labeling. The sensitivity of each of the distance determination methods to the non-interacting component was compared.

Mandibular advancement device in patients with obstructive sleep apnea : long-term effects on apnea and sleep

STUDY OBJECTIVES

To evaluate the long-term effects on apneas and sleep and the tolerability of a mandibular advancement device in patients with obstructive sleep apnea.

DESIGN

Prospective study.

SETTING

Department of Respiratory Medicine, University Hospital, Umeå, Sweden.

PATIENTS

Thirty-three consecutively treated patients.

INTERVENTIONS

Individually adjusted mandibular advancement devices.

MEASUREMENTS AND RESULTS

Polysomnographic sleep recordings on 1 night without the device and 1 night with the device were performed after 0.7 +/- 0.5 years (mean +/- SD) and after 5.2 +/- 0.4 years from the start of treatment. Nineteen of the 33 patients experienced a short-term satisfactory treatment result with an apnea-hypopnea index of < 10 events per hour and a satisfactory reduction in snoring. Fourteen patients were regarded as being insufficiently treated with the device. Seventeen of the short-term satisfactorily treated patients (90%) and 2 of the remaining patients continued treatment on a long-term basis. The apnea-hypopnea index was reduced by the device from 22 +/- 17 to 4.9 +/- 5.1 events per hour (p < 0.001) in these 19 long-term treatment patients, which did not differ from what was found at the short-term follow-up visits in these patients. Patients with their devices replaced or adjusted experienced a better long-term effect than patients still using their original devices (p < 0.05).

CONCLUSIONS

The long-term effect and tolerability of a mandibular advancement device are good in patients who are recommended the treatment on the basis of a short-term sleep recording, provided that the device is continuously adjusted or replaced with a new one when needed. A short-term follow-up is valuable in the selection of patients who will benefit from long-term treatment with a mandibular advancement device.

Protein compactness measured by fluorescence resonance energy transfer. Human carbonic anhydrase ii is considerably expanded by the interaction of GroEL

Nine single-cysteine mutants were labeled with 5-(2-iodoacetylaminoethylamino)naphthalene-1-sulfonic acid, an efficient acceptor of Trp fluorescence in fluorescence resonance energy transfer. The ratio between the fluorescence intensity of the 5-(2-acetylaminoethylamino)naphthalene-1-sulfonic acid (AEDANS) moiety excited at 295 nm (Trp absorption) and 350 nm (direct AEDANS absorption) was used to estimate the average distances between the seven Trp residues in human carbonic anhydrase II (HCA II) and the AEDANS label. Guanidine HCl denaturation of the HCA II variants was also performed to obtain a curve that reflected the compactness of the protein at various stages of the unfolding, which could serve as a scale of the expansion of the protein. This approach was developed in this study and was used to estimate the compactness of HCA II during heat denaturation and interaction with GroEL. It was shown that thermally induced unfolding of HCA II proceeded only to the molten globule state. Reaching this state was sufficient to allow HCA II to bind to GroEL, and the volume of the molten globule intermediate increased approximately 2.2-fold compared with that of the native state. GroEL-bound HCA II expands to a volume three to four times that of the native state (to approximately 117,000 A(3)), which correlates well with a stretched and loosened-up HCA II molecule in an enlarged GroEL cavity. Recently, we found that HCA II binding causes such an inflation of the GroEL molecule, and this probably represents the mechanism by which GroEL actively stretches its protein substrates apart (Hammarström, P., Persson, M., Owenius, R., Lindgren, M., and Carlsson, U. (2000) J. Biol. Chem. 275, 22832-22838), thereby facilitating rearrangement of misfolded structure.

[Toxicologic information center's hotline--well-received and cost-effective for the society]

Our evaluation using postal and interview surveys suggests that the telephone hotline service at the Swedish Poisons Information Centre ('Giftinformationscentralen') may be cost-effective for society. Advice to physicians--which was highly regarded for its speed, competence and applicability--was time-saving and facilitated better treatment. Similarly, advice direct to households eliminated many unnecessary emergency visits. Indeed, we found that the annual costs of running the centre can be completely offset by savings in health care resources. Improved outcomes, time savings for individual households, and reduced uncertainty for both households and health care staff provide additional benefits.

Estrogen receptor alpha in giant cell arteritis: a molecular genetic study

OBJECTIVE

Giant cell arteritis (GCA) predominantly affects postmenopausal women. Estrogen receptor alpha (ER alpha) accumulates in the cytoplasm of smooth muscle cells, activated mononuclear inflammatory cells and giant cells in the temporal arteries of GCA patients, as well as in smooth muscle cells in arteries from non-GCA controls. The aim of this study was to analyse whether this accumulation is related to structural aberrations in the ER alpha mRNA leading to a change in protein structure.

METHODS

Total RNA was extracted from inflamed temporal artery tissue in two GCA patients and from non-inflamed arteries in two non-GCA controls. Products from the nested RT-PCR of the cDNA were cloned and plasmid inserts of 20 different clones from each case were investigated using nucleotide sequence analysis.

RESULTS

A total of eight different types of transcripts lacking parts of the ER alpha mRNA were detected. Seven of these could be explained by alternative splicing. There were no significant differences between the GCA patients and the non-GCA controls in terms of the number of transcript variants.

CONCLUSION

The accumulated cytoplasmic ER alpha in temporal arterial tissue from elderly persons appears mainly to be of wild type. The main structural changes in the ER alpha mRNA may be due to alternative splicing. Somatic mutations of the ER alpha gene appear to be rare and it is therefore unlikely that they are involved in the pathogenesis of GCA.

Orthodontic side-effects of mandibular advancement devices during treatment of snoring and sleep apnoea

The aims of this study were to investigate possible orthodontic side-effects following the use of mandibular advancement devices (MAD) in adults with snoring and sleep apnoea. A second objective was to analyse the effect of the appliance design. Seventy-five patients treated with MAD and 17 reference patients were studied at follow-up after 2.5 +/- 0.5 years. In the test group, 47 patients were provided with soft elastomeric devices, while the remaining 28 patients received hard acrylic devices. The treatment induced a change in overjet of -0.4 +/- 0.8 mm (mean +/- SD) and a change in overbite of -0.4 +/- 0.7 mm (mean +/- SD). These changes were larger than those found in the reference group (P < 0.01). The odds ratio (OR) for the largest quartile of reduction in overjet was 3.8 in patients using hard acrylic devices compared with those using soft elastomeric devices (P < 0.05). A large reduction in overjet in patients using the hard acrylic devices was unrelated to the degree of mandibular protrusion by the device. The OR for a large reduction in overjet in patients using the soft elastomeric devices with a protrusion of 6 mm or above was 6.8 compared with smaller mandibular protrusions (P < 0.05). The results indicate that the orthodontic side-effects are small during the treatment of adult subjects with MAD for snoring and sleep apnoea, especially in patients using soft elastomeric devices with mandibular protrusions of less than 6 mm. The follow-up of patients treated with MAD is recommended, as individual patients may experience marked orthodontic side-effects.