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The macrolide and lincosamide (ML) resistance phenotype of 65 pigeon and 30 human Streptococcus gallolyticus strains was determined by the disk diffusion method. Constitutive resistance against the tested antibiotics was seen in 13 human and 28 pigeon strains. Simultaneous screening for the presence of erm(B) and mef(A) genes using PCR revealed that the erm(B) gene was present in 40 out of these 41 phenotypically resistant S. gallolyticus strains while the mef(A) gene was detected in only one resistant and one susceptible human-derived strain. The erm(B) genes of 10 human and 10 pigeon S. gallolyticus strains were sequenced and compared. Four human and seven pigeon strains possessed exactly the same sequence for the erm(B) gene. The sequence of the erm(B) gene of the remaining strains differed in one to five nucleotides. These findings could indicate a possible exchange of resistance genes between human and pigeon strains.

Ambulatory 24-hour double-probe pH monitoring seems to be the best test to measure reflux. Artifacts caused by intake of acid foods and beverages have to be excluded, necessitating a time-consuming manual review of the 24-hour data. Dietary restrictions used to bypass these artifacts would interfere with the normal daily life situation. Therefore, the influence of food and beverages ingested during the monitoring period was studied. Data from 252 patients who underwent double-probe pH monitoring were analyzed, first by visual inspection of the 24-hour tracing and second by leaving out the intake periods. As to the registration of gastroesophageal reflux, the inclusion or omission of meals and beverages hardly influenced the data. However, the registration of laryngopharyngeal reflux was severely biased by intake of food and beverages and other artifacts. Leaving out meals and beverages did not correct for all artifacts. Therefore, we recommend review of each laryngopharyngeal pH drop.

Antimicrobial resistance profiles were assessed in Enterococcus faecium, Enterococcus faecalis, and Enterococcus columbae strains isolated from racing pigeons (Columba livia). E. columbae is the most prevalent enterococcal species in the intestines of pigeons. Acquired resistance against the antimicrobials bambermycin, vancomycin, monensin, narasin, virginiamycin (cross-resistant with quinupristin/dalfopristin), avilamycin (cross-resistant with evernimicin), and ampicillin was not seen. Only for the antimicrobials tetracycline and tylosin was a frequent occurrence of resistance found in all three enterococcal species tested. Resistance to the fluoroquinolone antimicrobial enrofloxacin was present in E. columbae. Bacitracin resistance was seen in the species E. faecalis and E. faecium but not in E. columbae. High-level streptomycin resistance was found in E. columbae and in one E. faecium strain, whereas high-level gentamicin resistance was mainly associated with E. faecalis. The differences noted between the different species illustrate the difficulties related to the choice of indicator bacteria for antimicrobial resistance in the intestinal flora.

Background & Aims:Survivin is an inhibitor of apoptosis protein (IAP), which also is crucial for mitosis and cell cycle progression. IAPs participate in regulating Fas ligand-induced hepatic apoptosis. The aim was to study the contribution of survivin to hepatic apoptosis by generating transgenic mice lacking survivin. Methods:The survivin gene was inactivated in mice by homologous recombination in embryonic stem cells. Survivin+/− and survivin+/+ mice were generated and injected with the Fas agonistic antibody Jo2. Results:In 3 genetic backgrounds, survivin−/− embryos died before 4.5 days post coitum. Survivin+/− mice appeared normal, but liver lysates revealed aseline low-level activation of procaspase-8, Bid, procaspase-9, and procaspase-3, with accumulation of Bax, and release of cytochrome c, indicating a proapoptotic state. Intraperitoneal injection of low-dose Jo2 had no effect on survivin+/+ mice at 2 hours. However, in survivin+/− mice, Jo2 caused hemorrhagic necrosis of the liver, associated with prominent activation of the apoptotic pathway via the mitochondria, and up-regulation of hepatocellular expression of survivin in the cytosol, nuclei, and mitochondria. Isolated mitochondria from survivin+/− livers had more defects in oxidative phosphorylation after C2-ceramide exposure. Conclusions:Absence of survivin is incompatible with life. Although Jo2 induces expression of survivin, diminished baseline levels render the liver more sensitive to Fas, possibly due to functional effects on the mitochondria. This is the first in vivo documentation that survivin modulates caspase activation and that Fas-mediated hepatic apoptosis is regulated by survivin via mitochondrial pathways.

Background Rat models of peritoneal dialysis (PD) are useful for studying the physiology of peritoneal transport and evaluating new osmotic agents. Intraperitoneal (IP) solute concentrations and their evolution over time are easy to measure, but IP volume (IPV) is not. Direct volumetric measurements are the “gold standard,” but they are expensive and do not allow for repetitive measurements in the same animal. The indicator dilution technique is therefore used as an alternative. However, that technique is based on assumptions that are not always valid. The present study compares direct volume measurement with the indicator dilution technique [radioiodinated serum albumin (RISA)] to determine the IPV over time curves in a rat model of PD.Methods In series 1, 17 Sprague–Dawley rats were instilled IP with 25 mL 1.36% glucose dialysate through a Teflon catheter. In 9 animals, 0.35 mL dialysate was sampled and discarded at time points 0, 3, 15, 30, 60, 180, and 240 minutes. In the other 8 animals, no sampling was performed. At 240 minutes, all 12 animals were humanely killed, and direct volumetric measurements of IPV were performed. In series 2, rats were instilled IP with 25 mL 1.36% glucose dialysate containing 18.5 kBq 131I RISA. In 9 animals, dialysate was sampled at 0, 3, 15, 30, 60, 90, 120, 180, and 240 minutes for the construction of the RISA concentration-over-time curve, and to calculate the elimination constant Ke. At 30, 60, 180, and 240 minutes, dialysate was sampled in 6 different animals (total n= 24) to calculate IPV using the RISA dilution technique. Immediately afterward, the animals were humanely killed, and direct volumetric measurements of IPV were performed.Results In series 1, after 240 minutes’ dwell time, the IPV was lower in the sampled animals as compared with the non sampled animals (27.11 ± 1.85 mL vs 30.75 ± 0.59 mL, p= 0.001). In series 2, the evolution of RISA activity in the dialysate over time was described by piecewise linear regression, yielding 3288 – 8.2T counts (cts) for T < 52.72 minutes and 2973 – 1.99T counts for T > 52.72 minutes. The IPV was better predicted with a Kethat took into account the disappearance of RISA by sampling than with a Kethat took into account disappearance of RISA only by absorption.Conclusions If indicator dilution techniques are used to measure IPV, attention must be paid to the disappearance of the osmotic agent and the marker by multiple sampling. The best way to meet that goal is to use micropipettes to avoid large sample volumes.

Seven Enterococcus moraviensisand 16 Enterococcus haemoperoxidusas well as nine reference cultures of other enterococcal species obtained from the Czech Collection of Microorganisms were characterized using ribotyping with EcoRI and HindIII in the present work. The ribopatterns obtained by both restriction enzymes clearly distinguished all E. moraviensisand E. haemoperoxidusstrains from the other enterococci (E. faecalis, E. faecium, E. avium, E. raffinosus, E. pseudoavium, E. malodoratus) and they differentiated both species from each other as well. Although all strains were isolated from different sampling sites, many strains shared the same band patterns. E. moraviensisformed four ribogroups using EcoRI and two ribogroups using HindIII restriction enzyme. E. haemoperoxidusgave six different patterns with EcoRI and five using the HindIII restriction enzyme.

ABSTRACTThe prevalence of acquired resistance in 146 Enterococcus faeciumand 166 Enterococcus faecalisstrains from farm and pet animals, isolated in 1998 and 1999 in Belgium, against antibiotics used for growth promotion and for therapy was determined. Acquired resistance against flavomycin and monensin, two antibiotics used solely for growth promotion, was not detected. Avoparcin (glycopeptide) resistance was found sporadically in E. faeciumonly. Avilamycin resistance was almost exclusively seen in strains from farm animals. Resistance rates were higher in E. faeciumstrains from broiler chickens than in strains from other animal groups with tylosin and virginiamycin and in E. faecalisas well as in E. faeciumstrains with narasin and bacitracin. Resistance against ampicillin was mainly found among E. faeciumstrains from pets and was absent inE. faecalis. Tetracycline resistance occurred most often in strains from farm animals, while enrofloxacin resistance, only found inE. faecalis, occurred equally among strains from all origins. Resistance against gentamicin was very rare in broiler strains, whereas resistance rates were high in strains from other origins. It can be concluded that resistance against antibiotics used solely for growth promotion was more prevalent in E. faeciumstrains than in E. faecalisstrains. With few exceptions, resistance against the different categories of antibiotics was more prevalent in strains from farm animals than in those from pets.

ABSTRACTThe discriminatory power, speed, and interlaboratory reproducibility of tRNA intergenic length polymorphism analysis (tDNA-PCR) combined with capillary electrophoresis was evaluated for the identification of streptococci. This method was carried out in three different laboratories under highly standardized conditions for 54 strains belonging to 18 different species. It was concluded that interlaboratory reproducibility of tDNA fingerprints produced by means of capillary electrophoresis was sufficiently high to permit the exchange between different laboratories and the construction of common libraries which can be consulted for comparison with fingerprints obtained independently in separate laboratories. In a second step, 17 other species were included in the study and examined in one of the participating laboratories. All Streptococcusspecies studied, except S. mitis, S. oralis, S. parasanguinis, S. pneumoniae, S. thermophilus, and S. vestibularis, showed distinguishable tDNA fingerprints. A database of well-characterized strains was constructed to enable computer-aided identification of unknown streptococcal isolates.

In this chapter, a learning account is discussed as a potential explanation for the symptoms in multiple chemical sensitivity. Clinical evidence is scarce and anecdotal. A laboratory model provides more convincing results. After a few breathing trials containing CO2-enriched air as an unconditioned stimulus in a compound with harmless odor substances as conditioned stimuli, subjective symptoms are elicited and respiratory behavior is altered by the odors only. Also, mental images can become conditioned stimuli to trigger subjective symptoms. The learning effects cannot be explained by a response bias or by conditioned arousal, and they appear to involve basic associative processes that do not overlap with aware cognition of the relationship between the odors and the CO2inhalation. Learned symptoms generalize to new odors and they can be eliminated in a Pavlovian extinction procedure. In accordance with clinical findings, neurotic subjects and psychiatric cases are more vulnerable to learning subjective symptoms in response to odors. Consistent with a learning account, cognitive-behavioral treatment techniques appear to produce beneficial results in clinical cases. Several criticisms and unresolved questions regarding the potential role of learning mechanisms are discussed.

ABSTRACTtRNA intergenic spacer PCR (tDNA-PCR) was evaluated for its usefulness in the differentiation of enterococcal species of human and animal origin. This technique was carried out for 124 strains belonging to 17 enterococcal species and generated DNA fragments, which were separated by capillary electrophoresis. tDNA-PCR enabled us to discriminate for all species tested. Enterococcus faeciumshowed minor but reproducible differences with Enterococcus durans, while Enterococcus hiraewas easily distinguishable. Enterococcus avium, Enterococcus malodoratus, and Enterococcus raffinosusgenerated highly similar though distinctive patterns.

The growth-promoting antibiotic flavomycin (also called bambermycin, flavophospholipol and moenomycin) has a complex spectrum of activity against enterococci, with some species being naturally resistant and others susceptible. In this study, proteins added to Mueller-Hinton II medium had a strong deleterious effect on the activity of flavomycin, glucose had no effect and starch decreased the activity of flavomycin. The fatty substances Tween 80 and tributyrin increased the activity of flavomycin for several enterococcal species. Slight differences in the composition of the susceptibility test medium affected the MIC results obtained, indicating that strict standardization of the test medium is necessary.

ObjectivesLaryngopharyngeal reflux may play a role in the etiology of squamous cell cancer of the head and neck and contribute to complications in head and neck cancer patients after surgery or during radiotherapy.

Growing healthcare needs leverage the potential savings of using resources efficiently. To that end, ProMoBed is a comprehensive model that supports strategic planning of bed capacity in inpatient hospitals. The model consists of an extrapolation and simulation component, the former supplying input for the latter. The extrapolation model forecasts admission rates and the average Length of Stay for pathology groups, and corrects for demographic changes. Subsequently, the simulation model emulates the demand for bed capacity, and makes service-level based bed capacity suggestions. Additionally, the model uses the Shapley value principle to disaggregate the effects on demand for inpatient days due to different causes. Results from the extrapolation model are applied to regions in Belgium, showing expected divergence in inpatient day demand evolution.

ABSTRACTNonlipophilic corynebacteria associated with clinical and subclinical mastitis in dairy cows were found to belong to four species: Corynebacterium amycolatum, Corynebacterium ulcerans, Corynebacterium pseudotuberculosis, andCorynebacterium minutissimum. These species may easily be confused. However, clear-cut differences between C. ulceransand C. pseudotuberculosiswere found in their acid production from maltotriose and ethylene glycol, susceptibility to vibriostatic agent O129, and alkaline phosphatase. Absence of growth at 20°C and lack of a-glucosidase and 4MU-a-d-glycoside hydrolysis activity differentiatedC. amycolatumfrom C. pseudotuberculosisandC. ulcerans. The mastitis C. pseudotuberculosisstrains differed from the biovar equi and ovis reference strains and from caprine field strains in their colony morphologies and in their reduced inhibitory activity on staphylococcal ß-hemolysin.C. amycolatumwas the most frequently isolated nonlipophilic corynebacterium.

ABSTRACTOne hundred thirty-two glycopeptide-resistant Enterococcus faecium(GREF) isolates from different hospitals and pig and poultry farms in Belgium were compared on the basis of (i) their antibiotic susceptibilities, (ii) their SmaI pulsed-field gel electrophoresis (PFGE) patterns, and (iii) the organization of their Tn1546or related elements in order to detect possible phenotypic and genotypic relationships among both groups of isolates. Human and animal vanA-positive GREF isolates were found to have similar susceptibility patterns; they remained susceptible to gentamicin and were, in general, susceptible to ampicillin. PFGE demonstrated a very high degree of genomic heterogeneity in both groups of isolates. However, indistinguishable isolates were found within different farms or hospitals, and in two instances, epidemiologically unrelated pig and human isolates showed indistinguishable PFGE patterns. In total, eight different transposon types were identified, and all were related to the prototype transposon Tn1546. The two predominant types, Tn1546and type 2 transposons, which differed at three band positions, were present in both human and animal isolates. Type 2 transposons were significantly associated with pig isolates. The other types were seldom detected. These data suggest a possible exchange of glycopeptide resistance markers between animals and humans.

Experimental infections with four different rabbit enteropathogenic Escherichia coli (EPEC) biotypes were carried out in EPEC free rabbits, and intestinal colonisation was assessed by measuring semi-quantitatively the rectal colonisation. When the animals were infected for the first time shortly after weaning, the excretion followed an approximately identical course with all four EPEC: at 3-9 d post-infection all rabbits excreted the infecting EPEC strain in high quantities, and continued to do so for 1-2 wks. Rabbits that had survived such a colonisation with one EPEC, were protected against colonisation with strains belonging to other EPEC groups.

The antibiotic susceptibility pattern of 5. bovis strains isolated from pigeons was studied. In vitro, S. bovis strains were sensitive to penicillins, macrolides, lincomycin, tetracyclines, chloramphenicol and nitrofurans. However, the prevalence of acquired resistance against tetracyclines was approximately 40%. Sulphonamides and trimethoprim had little in vitro activity against 5. bovis while activity of the quinolone enrofloxacin and the aminoglycoside antibiotics, neomycin and gentamicin, were in or near to the intermediate range.The comparative efficacy of 5 antimicrobials administered via the drinking water for the treatment of experimental S. bovis infection in pigeons was also tested. Morbidity after intravenous inoculation of S. bovis in groups of pigeons treated with ampicillin, erythromycin, doxycycline, enrofloxacin and trimethoprim was 20%, 30%, 20%, 70% and 90%, respectively. Morbidity in an untreated control group was 90%.

Feeds supplemented with lincomycin, novobiocin, tylosin and chlortetra-cycline suppressed experimentally inoculated in vitro sensitive Staphylococcus aureus skin populations on young chickens. The same effects were seen with drinking water medications containing erythromycin and spiramycin. Funfeolidone-, bacitracin-, nitrovin- and virginiamycin-containing feeds and single intramuscular injections of macrolide antibiotics did not exert any detectable effects on these experimental skin colonizations.

Streptococcus bovis infection was diagnosed in pigeons from 20 lofts submitted for post mortem investigation. Clinical signs were very variable and ranged from hyperacute death to chronic lameness with arthritis. Lesions were generally unspecific except for single cases of muscle necrosis with purulent myositis. Histological examinations demonstrated the septicaemic nature of the infections.Intravenous inoculations of S. bovis resulted in prostration, long lasting loss of weight and polyuria. Microscopically purulent hepatitis and nephritis were the most characteristic lesions. After oral inoculation no clinical signs were seen.

Streptococcus bovis strains isolated from different lesions in pigeons were found to differ from most S. bovis asociated with mammals. S.bovis was only infrequently found in the gut and faeces of pigeons without streptococcal disease. The bacterium was also isolated from the crop and the pharynx of a minority of healthy pigeons.

We surveyed a series of surface waters and sewage treatment plants in Flanders (north of Belgium) for the presence of estrogenic activity and a xeno‐estrogenic compound para‐nonylphenol (NP), respectively. The surface waters of rural origin, used for drinking water production, were free of significant levels of estrogenic activity and NP (<1 µg/L). Domestic sewage, after proper treatment, appeared to be no major source of this chemical. Yet, in some industrial effluents and surface waters of highly industrialized regions, NP and/or estrogenic activity was prominent, that is, <1 to 122 µg NP/L and 11 to 42 µg NP/L, respectively. This is because of the ongoing use of NP polyethoxylates in industry. The response of the recombinant yeast estrogen assay to the environmental samples tested was not consistent with the detected concentrations of NP. Standard addition of a natural estrogen, 17β‐estradiol, generated no or a reduced response compared to the standard curve concentration. Application of humic acids to standard series of NP and 17β‐estradiol resulted in a dose‐dependent decrease of the estrogenic response. It appears that this bioassay is subject to considerable interferences due to the complexity of environmental samples. Parallel implementation of extensive chemical screening for xenobiotics and use of the bioassay are needed for adequate assessment of the potential estrogenic hazard to avoid false negative evaluations.

Different antibiotics and chemotherapeutics were tested for therapeutic efficacy in rabbits, in an experimental model using a Pasteurella multocidastrain which causes hyperacute septicaemia in this animal species. Only enrof1oxacin, administered in the drinking water at a concentration of 50-100 mg/l cured the rabbits, provided that a daily intake of 5 mg/kg body weight was achieved. The other drugs tested (tetracycline, spiramycin, erythromycin and a combination of sulfamerazine with trimethoprim), at doses recommended for rabbits, showed little or no activity at all, with the exception of chloramphenicol, which was only partially effective.

Sixty-eight methicillin-resistant Staphylococcusaureus strains were isolated from mastitis milk samples originating from 20 Belgian dairy herds. All these strains appeared to be representatives of one single strain which was probably of human origin. Evidence is presented indicating a rapid in vivoevolutionary change in this strain. The following characteristics were found to be variable: the production of β haemolysin inversely connected with fibrinolysin (staphylokinase) activity; the production of lipase, enterotoxin B and δ haemolysin; the resistances to neomycin, chloramphenicol, tetracyclines, methicillin and spectinomycin associated with constitutive or inducible macrolide resistance.

The clinical manifestations of three cases of infection with NAD (V-factor)-requiring Haemophilus-like bacteria in psittacines are described. Case 1 involved members of the Platycercus family and produced mainly respiratory signs. In case 2 only conjunctivitis was seen among cockatiels. The third case was a hand-reared African grey parrot which developed a peracute septicaemia. The Haemophilus-like bacteria isolated from the three cases differed from each other as well as from the known avian NAD-requiring Haemophilus and Pasteurella species.

Pseudomonas aeruginosa infection was a factor associated with heavy losses on a broiler farm. The organism was repeatedly isolated from air sac lesions similar to those commonly observed in E. coli complicated Chronic Respiratory Disease, and from oedematous lesions present predominantly in the head region of some of the affected chickens.Losses continued in successive batches of chickens until an all-in all-out policy was adopted, although the organism was still present in the drinking water.

Cases of Enterococcus hirae septicaemia are described in 10 different species of psittacine birds. In most of the cases other disease causes were not detected, and cytological examination confirmed the aetiological role of the bacteria isolated. Despite these findings, attempts to reproduce the disease in young budgerigars failed. The bacterium was isolated frequently from the faeces of healthy psittacine birds belonging to a wide range of species, and appeared to be member of the normal intestinal flora of these birds. The bacteriological diagnosis of E. hirae, and especially its differentiation from Enterococcus durons, is discussed.

Four cases of Streptococcus suis infection were diagnosed in psittacine birds and four others in zebrafinches, bullfinches, canaries and a duck. The main clinical and pathological manifestation was septicaemia with multiple sudden deaths in nestlings, young and adults. Other cases were solitary, with evidence for secondary involvement of S. suis. Four serotypable strains all belonged to serotype 9.

A description is given of an outbreak of acute staphylococcal dermatitis-septicaemia in 20-week-old broiler breeders. The preceding administration by feed of sulphadimidine (500 ppm) for 13 consecutive days is believed to have precipitated the disease. Results of antibiotic treatment are discussed.

Gastroesophageal reflux (GER) appears to be related to laryngeal carcinoma. Little is known about GER and gastropharyngeal reflux (GPR) in the laryngectomized patient. Therefore, GER and GPR were studied in laryngectomized patients. In 11 patients, 24-hour double-probe pH monitoring was performed in an ambulant setting. An optic fiberscope was used for the accurate positioning of the proximal probe in the upper esophageal sphincter. In 9 of 11 patients pathologic GPR was found. Four of these 9 patients had reflux in upright and supine position, 5 patients had reflux only in upright position. A high incidence of GPR in laryngectomized patients was found. These results raise the question whether all laryngectomized patients should be investigated for reflux and in the presence of pathologic reflux findings should be treated with reflux prophylaxis. © 1998 John Wiley & Sons, Inc. Head Neck 20: 619–622, 1998.

Staphylococcus aureusstrains originating from humans, cows, poultry, pigs, dogs and pigeons were characterised according to the biotyping scheme of Hájek and Maršálek (1971). All strains obtained from poultry, dogs and pigeons and the majority of bovine, human and porcine strains were classifiable as belonging to different biotypes. Two types were found to be present among poultry strains isolated in Europe and Japan. The porcine strains formed a heterogenic collection. One biotype predominated in the other host species. The characteristic S aureuswall teichoic acid (β-N-acetylglucosaminyl ribitol teichoic acid) was present in nearly all poultry and pig strains.

ABSTRACTBetween January 1992 and December 1996, Serpulina-like bacteria were demonstrated in intestinal tract lesions from 37 of 88 guinea pigs submitted to the University of Ghent in Ghent, Belgium, for necropsy because of disease and death from different unknown causes. All infected animals had a history of sudden death with minimal introductory clinical signs. Occasionally, they produced yellow, slimy feces or showed nervous signs, but the condition always had a fatal outcome within 24 h. When larger colonies of guinea pigs were involved, the disease spread very rapidly unless treatment with ronidazole was initiated. Lesions consisted of a catarrhal or hemorrhagic inflammation of the colon and cecum (typhlitis). Electron microscopy demonstrated the presence of large numbers ofSerpulina-like organisms adhering to the cecal mucosae of these animals. Attempts to isolate the agents failed. The organisms did not stain by an immunofluorescence technique for the detection ofSerpulina hyodysenteriae. The present data provide evidence that intestinal Serpulina-like organisms can be important as a cause of disease in guinea pigs.

Lactococcus lactissubsp. lactis, Lactococcus garvieaeand Lactococcus raffinolactiswere identified in samples from different domestic animal species, mainly in tonsils of ruminants, dogs and cats, and milk samples from cases of subclinical mastitis in dairy cows. Species differentiation was mainly based on SDS-PAGE analysis of whole-cell protein patterns. A comparison was made with results of biochemical activity tests and sensitivity patterns to clindamycin and oxacillin. These results were used to construct an improved identification scheme for lactococci from animal origin. By SDS-PAGE analysis of whole-cell proteins, Enterococcus seriolicidawas shown to be closely related to Lactococcus garvieae.