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F Lund

Publications and source records attributed to F Lund.

At least 19 recordsLinked to original sources
PubMed2005

Ochratoxin A producing Penicillium verrucosum isolates from cereals reveal large AFLP fingerprinting variability.

AIMS: To examine if molecular amplified fragment length polymorphism (AFLP) fingerprinting of the only ochratoxin A-producing species in European cereals, Penicillium verrucosum, can be used as a method in hazard analysis using critical control points (HACCP). METHODS AND RESULTS: A total of 321 isolates of P. verrucosum were isolated from ochratoxin A-contaminated cereals from Denmark (oats), UK (wheat and barley) and Sweden (wheat). Of these, 236 produced ochratoxin A as determined by thin layer chromatography; 185 ochratoxin A-producing isolates were selected for AFLP fingerprinting. A total of 138 isolates had unique AFLP patterns, whereas 52 isolates could be allocated to small groups containing from two to four isolates with similar AFLP patterns. A total of 155 clones were found among the 185 P. verrucosum isolates, thus 84% of the isolates may represent different genets of P. verrucosum. As the few isolates that were grouped often came from the same farm, and those groups that contained AFLP-identical isolates from different countries were morphotypically different. On single farms up to 35 clones were found. The few groups of ramets from the same genet indicated that a HACCP approach based on clones may require a very large number of AFLP analysis to work in practice, we recommend basing the HACCP approach on the actual species P. verrucosum. A more detailed characterization should rather be based on the profile of species present at different control points, or analysis of the mycotoxins ochratoxin A and citrinin in the isolates. Examination of 86 isolates with HPLC and diode array detection of P. verrucosum showed that 66% produced ochratoxin A, 87% produced citrinin, 92% produced verrucin and 100% produced verrucolone. CONCLUSIONS: Among 184 ochratoxin A-producing Penicillium verrucosum, 155 clonal lineages were indicated by AFLP fingerprinting, indicating a high genetical diversity, yet the species P. verrucosum is phenotypically distinct and valid. SIGNIFICANCE AND IMPACT OF THE STUDY: AFLP fingerprinting of Penicillium verrucosum indicates that genetic recombination takes place in this fungus.

Avena↗
PubMed2003

Penicillium verrucosum in wheat and barley indicates presence of ochratoxin A.

AIMS: The aims of this study were to isolate and identify ochratoxin A (OTA) producing fungi in cereals containing OTA and to determine the best selective and indicative medium for recovery of OTA producing fungi. METHODS AND RESULTS: Seventy-six wheat, barley and rye samples from Europe containing OTA and 17 samples without OTA were investigated using three different media, dichloran yeast sucrose agar (DYSG), dichloran rose bengal yeast extract sucrose agar (DRYES) and dichloran 18% glycerol agar (DG18). Hundred kernels were plated on each medium and the kind and number of fungal OTA producers were recorded as percentage of infestation. Penicillium verrucosum was the sole OTA producer found in cereals. The average percentage of infestation of P. verrucosum counts was recorded as 28.3% on DYSG, 10.3% on DRYES and 9.9% on DG18 on the OTA containing samples and 0.8% on DYSG, 0.4% on DRYES and 0.6% on DG18 for the samples without OTA. CONCLUSIONS: Penicillium verrucosum was the sole OTA producer in European cereals. Determination of P. verrucosum infestation and infection was best detected on DYSG after 7 days at 20 degrees C. The percentage of infestation of P. verrucosum found on DYSG and OTA content in cereals were correlated. More than 7% infestation of P. verrucosum indicated OTA contamination. SIGNIFICANCE AND IMPACT OF THE STUDY: The developed method could be used as a cereal quality control.

Culture Media↗
PubMed2002

Normal-mode-vortex interactions.

Standing surface waves that interact with a confined, vertical, vorticity field with zero net circulation are studied both analytically and experimentally. The surface waves are generated by vertical vibration, and constant vorticity injection is achieved by a rotating disk flush mounted in the cell. Experimental results are indicative of a local wave-vortex interaction (no dislocation), and a simple theoretical model is able to explain them in quantitative detail.

Journal Article↗
PubMed2000

[Tuberculosis of the hand].

Since 1985 there has been an increase in the incidence of skeletal tuberculosis in Denmark. This increase is attributed to a high incidence of tuberculosis among HIV-positive patients, elderly people and the increasing number of immigrants from areas with endemic tuberculosis. We present a case of hand tuberculosis in a young Somali male adult, where the tubercle bacilli find their way to the third metacarpal bone of the left hand, without a history of trauma or previous pulmonary tuberculosis. There was a delay in the treatment due to misdiagnosis of just three weeks. The abscess totally vanished two months after start of treatment.

Adult↗
PubMed2000

Computerized analysis of video fluorescein imaging (VFI) of the skin.

Video fluorescein imaging (VFI) is a new technique to continuously follow the development of fluorescence in the skin, i.e. blood inflow and perfusion, after intravenous injection of sodium fluorescein. The method is supplementary to other microcirculatory techniques for evaluation of peripheral arterial occlusive disease, particularly in critical ischaemia. In the present article we describe a totally computerized digital imaging processing system for evaluation and present results from a comparison between the evaluations of the appearance and development of the fluorescence in the sole of the foot using the computerized and the previously used manual techniques. With the computerized system the images are stored and correlated with the start of the injection. Regions of interest are then marked and a mean value of fluorescence intensity is calculated for each image. Using this computerized system the time required for evaluation has been shortened to about 10 min. The results of the comparison between the manual and computerized evaluations of appearance times showed that a significant correlation existed in all examined parts of the feet between the two techniques. The methods gave approximately the same results in regions with fluorescence appearance times between 20 and 50 s. With longer appearance times than approximately 50 s a systematic difference between the two techniques seemed to exist. In this interval shorter appearance times were measured with the computerized technique than with the manual technique. However, the clinical information with regard to prognosis would be relatively unchanged when the new computerized assessment technique and a new cut-off level for the appearance time are used. Also, regarding the development of fluorescence after the appearance time, expressed by the slope, a significant correlation was found between the manual and the computerized evaluation.

Aged↗
PubMed2000

Ultrasound scattering and the study of vortex correlations in disordered flows

In an idealized way, some turbulent flows can be pictured by assemblies of many vortices characterized by a set of particle distribution functions. Ultrasound provides a useful, nonintrusive, tool to study the spatial structure of vorticity in flows. This is analogous to the use of elastic neutron scattering to determine liquid structure. We express the dispersion relation, as well as the scattering cross section, of sound waves propagating in a "liquid" of identical vortices as a function of vortex pair correlation functions. In two dimensions, formal analogies with ionic liquids are pointed out.

Journal Article↗
PubMed1999

Generalized Griffith criterion for dynamic fracture and the stability of crack motion at high velocities.

We use Eshelby's energy momentum tensor of dynamic elasticity to compute the forces acting on a moving crack front in a three-dimensional elastic solid [Philos. Mag. 42, 1401 (1951)]. The crack front is allowed to be any curve in three dimensions, but its curvature is assumed small enough so that near the front the dynamics is locally governed by two-dimensional physics. In this case the component of the elastic force on the crack front that is tangent to the front vanishes. However, both the other components, parallel and perpendicular to the direction of motion, do not vanish. We propose that the dynamics of cracks that are allowed to deviate from straight line motion is governed by a vector equation that reflects a balance of elastic forces with dissipative forces at the crack tip, and a phenomenological model for those dissipative forces is advanced. Under certain assumptions for the parameters that characterize the model for the dissipative forces, we find a second order dynamic instability for the crack trajectory. This is signaled by the existence of a critical velocity V(c) such that for velocities V V(c) it is governed by K(II) not equal to 0. This result provides a qualitative explanation for some experimental results associated with dynamic fracture instabilities in thin brittle plates. When deviations from straight line motion are suppressed, the usual equation of straight line crack motion based on a Griffiths-like criterion is recovered.

Journal Article↗
PubMed1999

Scattering of dislocated wave fronts by vertical vorticity and the Aharonov-Bohm effect. I. Shallow water.

When a surface wave interacts with a vertical vortex in shallow water the latter induces a dislocation in the incident wave fronts that is analogous to what happens in the Aharonov-Bohm effect for the scattering of electrons by a confined magnetic field. In addition to this global similarity between these two physical systems there is scattering. This paper reports a detailed calculation of this scattering, which is quantitatively different from the electronic case in that a surface wave penetrates the inside of a vortex while electrons do not penetrate a solenoid. This difference, together with an additional difference in the equations that govern both physical systems, lead to a quite different scattering in the case of surface waves, whose main characteristic is a strong asymmetry in the scattering cross section. The assumptions and approximations under which these effects happen are carefully considered, and their applicability to the case of the scattering of acoustic waves by vorticity is noted.

Journal Article↗
PubMed1999

Scattering of dislocated wave fronts by vertical vorticity and the Aharonov-Bohm effect. II. Dispersive waves.

Previous results on the scattering of surface waves by vertical vorticity on shallow water are generalized to the case of dispersive water waves. Dispersion effects are treated perturbatively around the shallow water limit, to first order in the ratio of depth to wavelength. The dislocation of the incident wave front, analogous to the Aharonov-Bohm effect, is still observed. At short wavelengths the scattering is qualitatively similar to the nondispersive case. At moderate wavelengths, however, there are two markedly different scattering regimes according to whether the depth is smaller or larger than sqrt[3] times capillary length. In the latter case, dispersion and advection may compensate leading to a spiral interference pattern. The dislocation is characterized by a parameter that depends both on phase and group velocity. The validity range of the calculation is the same as in the shallow water case: wavelengths small compared to vortex radius, and low Mach number. The implications of these limitations are carefully considered.

Journal Article↗
PubMed1999

Intravenous hydroxyethylrutosides combined with long-term oral anticoagulation in atherosclerotic nonreconstructable critical leg ischemia: a retrospective study.

OBJECTIVE: To evaluate in a group of seriously diseased patients with nonreconstructable chronic critical leg ischemia (CLI), treated by a combination of i.v. hydroxyethylrutosides (HR)* and oral anticoagulation (AC) by warfarin, the short-term effects on the cutaneous microvascular blood perfusion of the soles of feet and especially the long-term clinical outcome in terms of amputation and death. DESIGN: A retrospective comparison between two groups of patients, HR + AC and a comparable reference group, fulfilling the same inclusion and exclusion criteria corresponding to the definition of CLI according to the Second European Consensus Document (1991). Clinical follow-up in both groups was made after 1, 3, 6, 12, and 24 months. SETTING: Patients were examined at university departments of clinical physiology with special interest in peripheral vascular disease, in cooperation with colleagues at university departments of surgery, internal medicine and dermatology of Karolinska Hospital, Södersjukhuset and Huddinge Hospital. PATIENTS: A total of seventy patients with CLI according to the definition of the Second European Consensus Document, 1991, ie, besides severe rest pain or ischemic lesions also a toe blood pressure < 30 mg Hg. Group with HR + anticoagulation (AC): 42 patients (19 diabetics, 23 nondiabetics). Reference group: 28 patients (18 diabetics, 10 nondiabetics). For distribution of age and toe blood pressure at baseline, see Table I. INTERVENTIONS: Therapy group: besides ordinary standard therapy, daily HR infusions for a mean period of 3.6 weeks + oral anticoagulation continued to the end of the study at 24 months. A comparable reference group on the same basic therapy but without the combination HR + AC. PARAMETERS IN EVALUATION: Short-term parameters: clinical data, skin temperature, and fluorescein imaging. Long-term outcome: amputation or death. RESULTS: Short-term and long-term results with HR + AC indicated that patients with severe CLI and very poor prognosis benefited in terms of survival and limb salvage from initial therapy with HR infusion combined with long-term oral anticoagulation. Results of this combined treatment seem at least comparable with those with i.v. prostacyclin analogies.

Administration, Oral↗
PubMed1997

Video fluorescein imaging of the skin: description of an overviewing technique for functional evaluation of regional cutaneous blood perfusion in occlusive arterial disease of the limbs.

In peripheral arterial occlusive disease (PAOD), and particularly in critical limb ischaemia, fluorescence recording of the skin after i.v. injection of sodium fluorescein provides an overviewing functional imaging of regional blood perfusion as revealed by a continuous, almost geographical, mapping of changes in the dynamic fluorescence pattern. Based on the previously used technique of rapid sequence flash photography introduced by Lund and Lund in 1973, a new video fluorescence imaging (VFI) technique has been developed and used in clinical routine. VFI has a broad versatility with non-touch access to areas of different size, such as the feet, hands or larger limb areas. Examples of application are the diagnosis of small artery disease, predictive prognosis of critical limb ischaemia, evaluation of distal outflow in connection with arterial reconstruction or pharmacotherapy of non-reconstructable critical ischaemia, as well as in decisions on amputation and assessment of amputation level. Thanks to its overviewing qualities with reproducible mapping of blood perfusion in standardized examination conditions, VFI would seem to have a well-justified role in angiology and above all in PAOD in both research and clinical routine work.

Adult↗
PubMed1996

Associated mycoflora of rye bread.

Penicillium roqueforti (27%), P. corylophilum (20%) and Eurotium species (15%) made up the important mycoflora associated with rye bread on 3425 identified fungi isolates. These fungi were dominant as spoilers of packaged rye bread in almost every month of a 4 year investigation. Penicillium decumbens (3%), Paecilomyces variotti (8%) and Aspergillus flavus (5%) were found more rarely, but were the major species found over periods of a few months. Penicillium commune (5%), P. solitum (4%), A. niger (4%) and Mucor species (2%) were a constant, but small, part of the total mycoflora of rye bread. Identification of the fungi in the production environment in a rye bread factory showed the locality of potential contamination sources. Elimination of the contamination sources by improved cleaning and disinfection procedures quickly resulted in a significant reduction in the frequency of mould growth in the packaged rye bread.

Aspergillus flavus↗
PubMed1996

Direct identification of the common cheese contaminant Penicillium commune in factory air samples as an aid to factory hygiene.

Creatine sucrose dichloran agar (CREAD) was used as a selective medium for Penicillium commune and related species found in air samples in a cheese factory. Using growth and simple colony characters on CREAD together with detection of indole metabolites with a filter paper method, it was possible to identify all 22 P. commune isolates from a total of 43 Penicillium isolates. Penicillium commune numbers on CREAD were compared with those found on a general isolation medium, dichloran 18% glycerol agar.

Air Microbiology↗
PubMed1995

Murine CD38: an immunoregulatory ectoenzyme.

CD38 is an ectoenzyme that utilizes NAD+ and is expressed by many cells of hematopoietic origin. Antibodies to CD38 potentiate many biological activities on lymphocytes, including induction of murine B-cell proliferation. In this article, Frances Lund and colleagues summarize information concerning the expression, enzymatic activity and signal transduction pathway utilized by murine CD38.

ADP-ribosyl Cyclase↗
PubMed1995

Peripheral artery disease in patients with coronary artery disease.

The prevalence of peripheral vascular disease in patients with coronary artery disease has been investigated in many different ways and depends on the diagnostic methods and the definition of the atherosclerotic manifestations in the different vascular beds. In this study we used the non-invasive methods digital volume pulse plethysmography and ankle and toe blood pressure measurements to identify arterial abnormalities in the lower limbs in 58 patients (49 males and 9 females; age 37-72 years) examined with coronary angiography. The prevalence of peripheral artery disease was 22%, in agreement with the results of most previous investigations. There was a tendency towards increasing prevalence of peripheral artery disease with more advanced coronary artery disease: 14% of the patients with no or minimal coronary atheromotous lesions, 18% of the patients with moderate coronary atheromotous lesions and 32% of the patients with marked coronary atheromotous disease. For this reason a non-invasive investigation of the peripheral arterial circulation should be included early in the clinical consideration of patients with chest pain or similar symptoms suggesting coronary heart disease. Toe pressure measurement appears to be the most appropriate technique being rather simple in management and also in evaluation of results.

Arteriosclerosis↗