Lameness in Piglets. Abrasions in Nursing Piglets and Transfer of Protection towards Infections with Streptococci from Sow to Offspring

A group of 175 newborn piglets were monitored with respect to development of abrasions and lameness. Lameness was diagnosed in 10.9% of the piglets. About every second litter was affected and around 75% of these diagnoses took place during the first 3 weeks of life. Skin lesions were present already on day 3. They increased in magnitude until day 10 and thereafter declined. They were generally bilateral and most commonly observed as abrasions over the carpal joints. Hocks, face and tails were affected in a similar way, but at lower magnitudes. Sole bruising was observed in 87% of the piglets on the third day of life, and moderate to severe lesions dominated until day 10. Thereafter the incidence decreased, indicating healing with time. Still 39% of the piglets were affected at day 17. There was a significant positive correlation between skin lesions of carpus and hock within all examination days in selected piglets with known identity (n = 48). Between day 10 and 17 significant positive correlations were found within all examination sites with exception of abdomen and teats. The offspring of sows treated against mastitis expressed more abrasions then piglets delivered by healthy sows and the mortality during the first 17 days postpartum was significantly higher among piglets delivered by sows treated for mastitis. The level of serum antibodies to Streptococcus equisimilis in eight dams decreased during the last month of gestation and a declining maternal immunity to S. equisimilis was demonstrated in all piglets (n = 47) during the first 5 weeks of life. During the first 2 weeks of life somewhat lower median levels of serum antibodies were recorded among the piglets that were treated against arthritis (n = 8).

Wound ventilation with carbon dioxide: a simple method to prevent direct airborne contamination during cardiac surgery?

Carbon dioxide (CO2) insufflation in the cardiothoracic wound cavity is used in open-heart surgery for prevention of arterial air embolism. The objective of this study was to investigate if CO2 insufflation may influence the rate of airborne contamination of the cardiothoracic wound. This was studied in a cardiothoracic wound cavity model that contained two 9 cm blood agar plates. Contamination rates were compared between a control without insufflation and insufflation with: (1) a thin open-ended tube or a gas-diffuser, (2) air or CO2, and (3) CO2 flows of 5 or 10 L/min. CO2 insufflation at 5 L/min with an open-ended tube resulted in a contamination rate almost four times that of the control (P = 0.01), whereas with the gas-diffuser the contamination rate decreased (P = 0.01). With the gas-diffuser, air insufflation at 5 L/min markedly reduced the contamination rate compared with the control (P < 0.001), but was less protective than CO2 insufflation at the same flow (P < 0.001). With both gases, the contamination rate was particularly low close to the gas-diffuser (P < 0.001). Increasing the CO2 flow from 5 to 10 L/min reduced the average contamination rate in the model from 30% to 22% (P < 0.001) of the control. At a CO2 flow of 10 L/min the contamination rate within 9 cm of the gas-diffuser was 14% of the control. Intraoperative wound ventilation with CO2 using a gas-diffuser may not only prevent air embolism, but may also significantly reduce the risk of airborne contamination and postoperative wound infection in cardiac surgery. In contrast, insufflation with an open-ended tube substantially increases these risks.

Spin splitting of s and p states in single atoms and magnetic coupling in dimers on a surface

Electronic states of magnetic atoms (Mn, Fe, and Co) and artificially assembled dimers (Mn2, Fe2, and Co2) on a NiAl(110) surface were probed by scanning tunneling spectroscopy at 17 K. Resonance peaks characteristic of each adsorbed species were observed in the unoccupied density of states. Comparison of the measured spectra with calculations by density functional theory revealed spin splitting in the unoccupied states with s and p characters for the single magnetic adatoms and addimers. The magnitude of the resonance splitting for the adatoms increased with the calculated values of magnetic moments. The resonance structures for the addimers exhibited signatures of their internal magnetic coupling.

Validation of fractional moving blood volume measurement with power Doppler ultrasound in an experimental sheep model

OBJECTIVE

To compare fractional moving blood volume (FMBV) estimation using power Doppler ultrasound (PDU) with blood flow estimation using radioactive microspheres (RMS) for evaluation of fetal organ blood perfusion.

METHODS

Blood flow was measured in the adrenal gland of nine exteriorized fetal lambs. Five fetal lambs underwent total umbilical cord occlusion in order to induce changes in the adrenal blood flow (asphyxia group). Four lambs were used as sham controls (control group). Three RMS injections, with coincident PDU recordings of the adrenal gland, were performed in each lamb. In the asphyxia group, measurements were taken before the cord occlusion, 5 min later and when the mean blood pressure decreased below 25 mmHg. In the control group, the measurements were done with an interval of 5 min. FMBV normalized for attenuation of PDU signals, and mean pixel intensity (MPI) were estimated offline. After completion of the study, adrenal blood perfusion was calculated according to the reference sample microsphere technique, using the isotope activity and expressed in mL/min/100 g. The correlation between RMS and FMBV and MPI, respectively, was analyzed individually for each lamb.

RESULTS

In the asphyxia group, all lambs showed a marked reduction in the adrenal blood perfusion towards the third RMS injection. In the control group, the adrenal perfusion showed small variations throughout the experiment. In the total material, there was a higher correlation between FMBV and RMS (median, r = 0.90; range, 0.43-0.99) than between MPI and RMS (median, r = 0.55; range, -0.53 to 0.99).

CONCLUSION

The FMBV method of quantifying PDU signals correlates highly with blood flow perfusion estimation using RMS in the fetal lamb adrenal gland.

Effect of CO2 insufflation on the number and behavior of air microemboli in open-heart surgery: a randomized clinical trial

BACKGROUND

The risks that the presence of air microemboli implies in open-heart surgery have recently been emphasized by reports that their number is correlated with the degree of postoperative neuropsychological disorder. Therefore, we studied the effect of CO2 insufflation into the cardiothoracic wound on the incidence and behavior of microemboli in the heart and ascending aorta.

METHODS AND RESULTS

Twenty patients undergoing single-valve surgery were randomly divided into 2 groups. Ten patients were insufflated with CO2 via a gas diffuser, and 10 were not. Microemboli were ascertained by intraoperative transesophageal echocardiography (TEE) and recorded on videotape from the moment that the aortic cross-clamp was released until 20 minutes after end of cardiopulmonary bypass (CPB). The surgeon performed standard de-airing maneuvers without being aware of TEE findings. Postoperatively, a blinded assessor determined the maximal number of gas emboli during each consecutive minute in the left atrium, left ventricle, and ascending aorta. The 2 groups did not differ in the usual clinical parameters. The median number of microemboli registered during the whole study period was 161 in the CO2 group versus 723 in the control group (P<0.001). Corresponding numbers for the left atrium were 69 versus 340 (P<0.001), left ventricle 68 versus 254 (P<0.001), and ascending aorta 56 versus 185 (P<0.001). In the CO2 group, the median number of detectable microemboli after CPB fell to zero 7 minutes after CPB versus 19 minutes in the control group (P<0.001).

CONCLUSIONS

Insufflation of CO2 into the thoracic wound markedly decreases the incidence of microemboli.

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.