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PubMed2001

Genetic diversity among Mycoplasma species bovine group 7: clonal isolates from an outbreak of polyarthritis, mastitis, and abortion in dairy cattle.

A comprehensive genetic analysis of 60 Mycoplasma sp. bovine group 7 isolates from different geographic origins and epidemiological settings is presented. Twenty-four isolates were recovered from the joints of calves during sporadic episodes of polyarthritis in geographically distinct regions of Queensland and New South Wales, Australia, including two clones of the type strain PG5O. A further three Australian isolates were also recovered from the tympanic bulla, retropharyngeal lymph node and the lung and another three isolates had unconfirmed histories. Six isolates originated from Germany, Portugal, Nigeria, and France. Twenty-four epidemiologically related isolates of Mycoplasma sp. bovine group 7 were recovered from multiple tissue sites and body fluids of infected calves with polyarthritis, mastitic milk, and from the stomach contents, lung and liver from aborted foetuses in three large, centrally managed dairy herds in New South Wales, Australia. Restriction endonuclease analysis (REA) of genomic DNA differentiated 29 Cfol profiles among these 60 isolates and grouped all 24 epidemiologically related isolates in a defined pattern showing a clonal origin. Three isolates of this clonal cluster were recovered from mastitic milk and the synovial exudate of clinically-affected calves and appeared sporadically for periods up to 18 months after the initial outbreak of polyarthritis indicating a persistent, close association of the organism with cattle in these herds. The Cfol profile representative of the clonal cluster was distinguishable from profiles of isolates recovered from multiple, unrelated cases of polyarthritis in Queensland and New South Wales and from other countries. All 24 isolates from the clonal cluster possessed a plasmid (pBG7AU) with a molecular size of 1022 bp. DNA sequence analysis of pBG7AU identified two open reading frames sharing 81 and 99% DNA sequence similarity with hypothetical replication control proteins A and B respectively, previously described in plasmid pADB201 isolated from M. mycoides subspecies mycoides. Other isolates of bovine group 7, epidemiologically unrelated to the clonal cluster, including two clones of the type strain PG5O, possessed a similar-sized plasmid. These data confirm that Mycoplasma sp. bovine group 7 is capable of migrating to, and multiplying within, different tissue sites within a single animal and among different animals within a herd.

Abortion, Veterinary↗
PubMed2002

Expression of extracellular matrix components in a highly infiltrative in vivo glioma model.

This work demonstrates the expression of extracellular matrix (ECM) components in a highly infiltrative brain tumor model developed by simple inoculation of spheroids from five human glioma biopsy tissues directly into the brains of immunodeficient rats. Non-invasive tumors derived from one glioblastoma biopsy specimen and two glioma cell lines (D-54MG and U-251MG) were also included in this study. The extent of tumor cell infiltration was studied using a pan-human monoclonal anti-vimentin antibody. The cellular origin for several of these ECM components was identified using human-specific monoclonal antibodies and polyclonal antibodies detecting epitopes from both species. Immunostaining revealed a diffuse parenchymal staining of glioma-produced tenascin, whereas vitronectin was produced mainly by the invading glioma cells. ECM components such as laminin, fibronectin and collagen type IV were most probably produced by the host and were mainly associated with the blood vessels in the tumors. However, some parenchymal staining with regional variations was observed. The expression pattern of these components was different in cell lines tumors as compared to the biopsy specimen tumors. The alpha3 and beta1 integrin subunits were mainly observed in areas of tumor cell invasion in the invasive tumors. In conclusion, the observed staining patterns clarify the cellular origin and indicate the possible biological function of tenascin, vitronectin, laminin, fibronectin and collagen type IV in these highly invasive malignant tumors of glial origin.

Animals↗
PubMed2004

MusLABEL: a program to model striated muscle A-band lattices, to explore crossbridge interaction geometries and to simulate muscle diffraction patterns.

The program MusLABEL has been devised as a simple aid both in understanding the origin and appearance of fibre diffraction patterns from helical structures and also to simulate the structure and some features of the diffraction patterns from striated muscles and their filament components. Helices are common as preferred conformations in both natural and synthetic macromolecules (e.g. DNA, alpha -helices, polysaccharides, synthetic polymers), and they also occur frequently in extended macromolecular aggregates (e.g. actin filaments, myosin filaments, microtubules, amyloid filaments etc). For this reason, a simple way of visualising the kinds of diffraction patterns that these filament structures can give, particularly for the actin and myosin filaments in muscle, can have educational value and can also be useful as a quick means of evaluating possible symmetries in structural interpretations of diffraction data before embarking on full helical diffraction analysis. A feature of the MusLABEL program is that, when a particular kind of A-band lattice has been set up, for example for vertebrate striated muscle or insect flight muscle, additional parameters can be defined both to describe the limits to the azimuthal and axial ranges over which a myosin head can search for an actin binding site and also to describe the size and position of an actin 'target area' assuming that the azimuthal position of an actin monomer has a large effect in determining whether or not a myosin head can bind to it. By this means the effects of lattice geometry on head attachment can be explored and the diffraction effects of specific labelling patterns on actin can be calculated and simulated. The MusLABEL program, running under Microsoft Windows, is available free on the CCP13 website (www.ccp13.ac.uk) where further documentation is given.

Animals↗
PubMed1992

Information for Mandarin tones in the amplitude contour and in brief segments.

While the tones of Mandarin are conveyed mainly by the F0 contour, they also differ consistently in duration and in amplitude contour. The contribution of these factors was examined by using signal-correlated noise stimuli, in which natural speech is manipulated so that it has no F0 or formant structure but retains its original amplitude contour and duration. Tones 2, 3 and 4 were perceptible from just the amplitude contour, even when duration was not also a cue. In two further experiments, the location of the critical information for the tones during the course of the syllable was examined by extracting small segments from each part of the original syllable. Tones 2 and 3 were often confused with each other, and segments which did not have much F0 change were most often heard as Tone 1. There were, though, also cases in which a low, unchanging pitch was heard as Tone 3, indicating a partial effect of register even in Mandarin. F0 was positively correlated with amplitude, even when both were computed on a pitch period basis. Taken together, the results show that Mandarin tones are realized in more than just the F0 pattern, that amplitude contours can be used by listeners as cues for tone identification, and that not every portion of the F0 pattern unambiguously indicates the original tone.

Adult↗
PubMed1999

Cardiovascular drugs: discrepancies in demographics between pre- and post-registration use.

OBJECTIVES: To study discrepancies in demographic characteristics between patients participating in pre-registration phase III trials of cardiovascular drugs, registered in the Netherlands, and patient populations in daily practice representing the actual users of the drugs after registration. METHODS: Comparison of age and sex distribution in registration files of 15 cardiovascular drugs [angiotensin-converting enzyme (ACE)inhibitors/angiotensin II receptor antagonists, calcium channel blockers, beta-adrenergic blocking agents, vasodilators, HMG-CoA reductase inhibitors and thrombolytics] with patients selected from a general practitioner (GP) registration database, who had received prescriptions for drugs from the therapeutic classes for the registered indications (hypertension, hypercholesterolaemia or angina pectoris) or were diagnosed with myocardial infarction. Moderate discrepancy was defined as more than 10% difference between the populations, large discrepancy by more than 20% difference. Clinical trials were also analysed by region of trial performance with respect to patient selection criteria, differences in male/female ratios and ethnic origin of patients. RESULTS: Phase III clinical trials in registration files of drugs registered for hypertension, angina pectoris and myocardial infarction had a moderate to large under-representation of female patients. Patients aged more than 65 years, who accounted for more than 50% of drug use indicated for hypertension, angina pectoris and myocardial infarction, were under-represented in the clinical trials of drugs registered for all indications. Trials performed in North America included relatively fewer female patients compared with European trials, and showed different patterns in the ethnic origin between indications. CONCLUSIONS: Clinically relevant subgroups of cardiovascular patients are under-represented in pre-registration phase III trials. These findings concern major areas of cardiovascular diseases, i.e. hypertension, hypercholesterolaemia, angina pectoris and myocardial infarction. Widely used therapeutic classes of drugs are affected and regional differences in trial performance are present.

Adult↗
PubMed1987

The neostriatal mosaic: III. Biochemical and developmental dissociation of patch-matrix mesostriatal systems.

In the previous paper (Gerfen et al., 1987) mesostriatal dopaminergic neurons were shown to be subdivided into dorsal and ventral tiers that project to the striatal matrix and patch compartments, respectively. The present study provides experimental evidence that these patch-matrix mesostriatal dopaminergic systems are biochemically and developmentally distinct. A 28 kDa calcium-binding protein (CaBP, or calbindin-D28 kDa) is expressed in dorsal tier mesostriatal dopaminergic neurons. The distribution of such neurons, located in the ventral tegmental area, dorsal tier of the substantia nigra pars compacta, and retrorubral area, matches that of dopaminergic neurons that project to the striatal matrix. Dopaminergic neurons that do not express CaBP--those in the ventral tier of the pars compacta and in the pars reticulata--are distributed in a pattern that matches the origin of the dopaminergic projection to the striatal patches. During development, dopaminergic afferents to the striatal patch compartment are in place prior to the development of those to the matrix. Injections of the neurotoxin 6-hydroxydopamine (6-OHDA) into the striatum of newborn rats result in a selective and long-lasting depletion of dopaminergic afferents in the striatal patches. The later-developing matrix projection is relatively spared by such lesions. The distribution of surviving dopaminergic neurons, labeled with tyrosine hydroxylase (TH) immunoreactivity, matches the pattern of dorsal tier neurons previously shown to provide inputs to the matrix. Surviving neurons also express CaBP immunoreactivity and have dendrites that spread mediolaterally, in the plane of the pars compacta. On the other hand, those neurons that project to the patches are selectively lesioned by the neonatal 6-OHDA striatal injections, do not express CaBP, and have dendrites that are directed ventrally into the pars reticulata.

Animals↗
PubMed1976

Precision of reinnervation of original postsynaptic sites in frog muscle after a nerve crush.

Regenerating neuromuscular junctions in the cutaneous pectoris muscle of the frog were examined by light and electron microscopy up to three months after crushing the motor nerve. The aim was to determine the precision of reinnervation of the original synaptic sites. More than 95% of the original postsynaptic membrane is recovered by nerve terminals and little, if any, synaptic contact is made on other portions of the muscle fibre surface. Even after prolonged denervation when the Schwann cells have retracted from 70-80% of the postsynaptic membrane, regenerating terminals return to and cover a large fraction of it. Although synapses are confined to the original synaptic sites, the pattern of innervation of muscle fibres is altered in several ways: (a) regenerating axon terminals can fail to branch leaving small stretches of postsynaptic membrane uncovered; (b) two terminal branches can lie side by side over a stretch of postsynaptic membrane normally occupied by one terminal; and (c) after growing along a stretch of postsynaptic membrane on one muscle fibre, terminals can leave it to end either in extracellular space or on the postsynaptic membrane of another fibre. Altogether the results demonstrate a strong and specific affinity between the original synaptic sites and regenerating nerve terminals.

Animals↗
PubMed2001

Corticotectal and corticostriatal projections from the frontal eye fields of the cat: an anatomical examination using WGA-HRP.

Corticofugal projections from the frontal eye fields (FEF) are believed to access the superior colliculus (SC) directly (i.e., monosynaptically) and indirectly (i.e., multisynaptically) through the basal ganglia. The present results suggest that these two pathways are derived from largely segregated populations of corticofugal neurons. Furthermore, while the different subregions of the FEF from which these pathways originate have different termination patterns in the basal ganglia (i.e., striatum, ST), they share a common termination pattern in the SC. Injections of wheat germ agglutinin-horseradish peroxidase (WGA-HRP) into the two major subdivisions of the FEF (presylvian and cruciate sulci) resulted in dense label in both the ST (bilaterally) and the SC (ipsilaterally). Corticostriatal labeling was found in the caudal part of the head of the caudate nucleus (heaviest ipsilaterally), with labeling from cruciate injections located ventromedial to that produced by presylvian injections. Only presylvian injections resulted in labeling in the putamen. Retrograde tracing experiments demonstrated that both presylvian and cruciate corticostriatal projections originated from neurons in lamina III and the upper aspects of lamina V. An additional but small group of presylvian corticostriatal projections was found in lamina VI. Corticotectal terminal labeling was restricted to the deep laminae of the SC and was derived exclusively from lamina V neurons in cortex. They differed from their corticostriatal counterparts in laminar/sub-laminar location and in soma sizes.

Animals↗
PubMed2002

Hormone receptor immunohistochemistry and human papillomavirus in situ hybridization are useful for distinguishing endocervical and endometrial adenocarcinomas.

Determining the origin of uterine adenocarcinomas can be difficult in biopsy and curettage specimens because the morphologic spectrum of endocervical and endometrial adenocarcinomas overlaps. In addition, in hysterectomy specimens the primary site is often equivocal for tumors that involve predominantly the lower uterine segment and endocervix and lack identifiable precursor lesions. We assessed the value of immunohistochemistry for estrogen and progesterone receptors and in situ hybridization for human papillomavirus DNA detection in making this clinically relevant distinction. We evaluated a set of 48 adenocarcinomas of unequivocal origin (24 endocervical carcinomas and 24 endometrial endometrioid carcinomas without cervical extension) and then tested seven lower uterine segment/endocervical carcinomas of equivocal origin to determine whether patterns established in the initial set would permit definitive assignment of primary site for the equivocal set. Only one (4.2%) of 24 endocervical carcinomas was positive for both estrogen receptor and progesterone receptor, whereas 18 (75%) of 24 endometrial carcinomas were positive for estrogen receptor and 23 (95.8%) of 24 endometrial carcinomas were positive for progesterone receptor (p <0.001, chi2 test). Human papillomavirus DNA was detected in 16 (66.7%) of 24 endocervical carcinomas and in none of 24 endometrial carcinomas (p <0.001, chi2 test). Of the seven tumors of equivocal origin, five could be definitively classified as either endocervical or endometrial in origin based on their demonstration of a characteristic profile with these assays (either estrogen receptor/progesterone receptor-negative/human papillomavirus-positive, consistent with endocervical origin or estrogen receptor/progesterone receptor-positive/human papillomavirus-negative, consistent with endometrial origin). We conclude that hormone receptor immunohistochemistry and human papillomavirus in situ hybridization are useful for distinguishing endocervical and endometrial adenocarcinomas. The clinical utility of these techniques should be evaluated in studies that include curettage and biopsy specimens.

Adenocarcinoma↗
PubMed2004

Molecular epidemiology of avian pathogenic Escherichia coli (APEC) isolated from colisepticemia in poultry.

The molecular biology and epidemiology of 150 avian pathogenic Escherichia coli strains (APEC) isolated from septicemic poultry in Germany was investigated by serotyping, pulsed field gel electrophoresis (PFGE), and polymerase chain reaction (PCR). Only 49.6% of the isolates could be grouped to serogroups O1, O2, and O78. Macrorestriction analyses data revealed two large clonal groups (clusters I and II) among the APEC strains with a similarity of 60.9% to each other. An association between restriction pattern and serogroup or origin of the strains was only present in a few subgroups of each clusters I and II, but was not evident. In contrast, our data revealed distinct combinations of virulence-associated genes in that 51.2% of the O2-strains harboured a combination of the genes fyuA, irp2, iucD, tsh, vat, fimC, and colV and 36.4% of the O78-strains possessed the same gene combination with exception of vat. With 34 different gene combinations the non-O1, -O2, -O78 isolates revealed a higher variability in their virulence gene pattern than O1-, O2-, and O78-strains with 6, 13, and 9 patterns, respectively. Our data indicate only a limited association between the virulence gene pattern and the serogroup of APEC strains and question the sensitivity of O-typing for APEC identification without the application of further diagnostic tools. Although a limited number of APEC clones exist, horizontal gene transfer seems to be common in these pathogens. These findings strengthen further research on the population structure of APEC and may be the reason for the lack of clear definition of this common E. coli pathotype.

Animals↗
PubMed1989

Cellular contribution to symmetrical forelimbs from triploid-marked "polarizing region" in the embryo of axolotl, Ambystoma mexicanum.

Grafts of posterior tissue placed anterior to the limb bud in the salamander embryo exert a polarizing influence. To explain this result, the idea that the anteroposterior axis of the developing forelimb is polarized by a diffusible morphogen has been proposed. An alternative hypothesis, and the working hypothesis of the present study, is that the polarization of the developing salamander forelimb is accomplished by short-range cellular interactions resulting in intercalation rather than by the more global influence of a diffusible morphogen. One prediction of this intercalation hypothesis is that cells will be contributed to the limb from the "polarizing tissue." To test this idea, grafts of triploid marked polarizing tissue were implanted anterior to the limb bud in 82 diploid axolotl embryos at stages 32-34 of development. A total of 27 (33%) of the limbs that resulted were symmetrical and ranged in complexity from one to seven digits. Histological analysis of a subgroup of the original symmetrical limbs revealed that mesodermally derived tissues in the anterior side of these limbs (the side which formed as a duplication in response to the influence of the graft) contained high percentages of trinucleolate cells (muscle, 12.1%; connective tissue tissue, 12.5%; and cartilage, 13.4%) when compared to similar tissues in the posterior side of the same symmetrical limbs (muscle, 1.8%; connective tissue , 0.7%; and cartilage, 0.6%). When symmetrical limbs were amputated, 73% regenerated symmetrical limbs. When these regenerated limbs were again amputated, 63% formed symmetrical secondary regenerates. Histological analysis of the first generation of regenerated limbs revealed that the pattern of distribution of trinucleolate cells in each regenerate was similar to the pattern seen in the original symmetrical limb. These results indicate that there is considerable cellular contribution to the anterior side of the symmetrical forelimb from the mesoderm of grafted "polarizing tissue." This result supports the idea that short-range cellular interaction are sufficient for formation of symmetrical forelimbs in salamander embryos.

Ambystoma↗
PubMed1981

Pattern of group I fibre projections from ankle flexor and extensor muscles in man.

Variations in the H-reflex of soleus, tibialis anterior, quadriceps and short head of biceps femoris muscles were studied in normal man, preceded by a conditioning stimulus applied to either gastrocnemius medialis, the inferior branch of soleus or the common peroneal nerve. The observed variations were evoked by low threshold afferents, had a very short latency suggesting oligosynaptic linkage and disappeared during a selective ischaemic blockade of group I fibres; they were therefore regarded as due to group I fibre stimulation. Biphasic variations were observed in almost all cases: evidence is presented that the early low threshold effects, facilitatory for synergistic and inhibitory for antagonistic motoneurone pools, are due to stimulation of Ia fibres, while the subsequent opposite effects which had a slightly higher threshold are Ib in origin. Even though the pattern of projections of group I fibres from ankle flexors and extensors is qualitatively the same in normal man as in the spinal cat, large quantitative differences are observed; in normal man the effects of group I fibres from ankle flexors and extensors upon close synergistic and direct antagonistic motoneurone pools are weak, and often negligible, whereas they are extremely potent upon quadriceps motoneurones.

Adult↗
PubMed1998

Electrophysiological and morphological features of rat claustral neurons: an intracellular staining study.

The electrophysiological and morphological features of neurons in the rat rostral claustrum were examined using intracellular recording and staining methods in vivo. A total of 31 neurons were analysed electrophysiologically, and 21 of these were stained well with intracellular biocytin injection. The following electrophysiological properties were analysed by intracellular current injection: firing properties, the shape of single action potentials and input resistance. The firing patterns of the claustral neurons seemed to be similar to those of regular spiking cells in the cerebral cortex. They had action potentials with a maximum rate of rise much higher than that of fall, and showed spike-frequency adaptation during long depolarizing pulses. The morphological analysis demonstrated that the claustral neurons were of various types: the somata were polygonal, triangular, ovoid, round, or fusiform, sometimes with a stout dendrite. Such a dendrite extended toward the superficial layers in the more rostral orbital cortex, and was revealed to be a distorted apical dendrite by a three-dimensional computer-aided system. The embryological origin of the claustrum has been a matter of controversy: two main hypotheses of cortical germinal origin and ganglionic eminence origin. Considering the firing patterns and morphological features, the present findings suggest that the neurons in the rostral claustrum share some physiological characteristics with cortical neurons in rats.

Action Potentials↗
PubMed1996

Global patterns of linkage disequilibrium at the CD4 locus and modern human origins.

Haplotypes consisting of alleles at a short tandem repeat polymorphism (STRP) and an Alu deletion polymorphism at the CD4 locus on chromosome 12 were analyzed in more than 1600 individuals sampled from 42 geographically dispersed populations (13 African, 2 Middle Eastern, 7 European, 9 Asian, 3 Pacific, and 8 Amerindian). Sub-Saharan African populations had more haplotypes and exhibited more variability in frequencies of haplotypes than the Northeast African or non-African populations. The Alu deletion was nearly always associated with a single STRP allele in non-African and Northeast African populations but was associated with a wide range of STRP alleles in the sub-Saharan African populations. This global pattern of haplotype variation and linkage disequilibrium suggests a common and recent African origin for all non-African human populations.

Africa↗
PubMed1998

Monoclonal expansion of synoviocytes in rheumatoid arthritis.

OBJECTIVE: To examine whether synoviocytes from patients with rheumatoid arthritis (RA) have a stronger growth ability than those from patients with osteoarthritis (OA), and to determine whether these synoviocytes clonally expand in situ. METHODS: Synovial tissues from 13 RA patients and 4 OA patients were cultured, and their ability to form colonies in soft agarose was examined. RA and OA synoviocytes were also examined in varying concentrations of fetal calf serum (FCS)-containing medium to test the effects of FCS on colony formation. DNA was extracted from clones with colony-forming ability in nonpannus lesions and from synoviocytes in pannus lesions. Restriction fragment length polymorphism (RFLP) analysis was used to examine phosphoglycerate kinase 1 (PGK-1) gene patterns. Production of cytokines by these cells was also assessed. RESULTS: All 13 RA synoviocytes exhibited colony formation, whereas none of the 4 OA synoviocytes did. This tendency was also seen with all of the concentrations of FCS examined, although growth varied in a dose-dependent manner. In contrast to OA synovial clones, cloned RA synoviocytes obtained from colonies exhibited a partial RFLP PGK-1 gene pattern, suggesting that the clones originated from monoclonal cells. Of note, 3 of 7 noncloned synoviocytes from pannus lesions exhibited a monoclonal pattern. Pannus cells produced high levels of transforming growth factor beta and platelet-derived growth factor. CONCLUSION: These findings suggest that synoviocytes with a strong growth ability are present in the rheumatoid synovium, and that these cells expand monoclonally, particularly in pannus lesions.

Adult↗
PubMed1989

Abnormal spatial patterns of elbow muscle activation in hemiparetic human subjects.

The patterns of electromyographic (EMG) activity in spastic-paretic and contralateral elbow muscles of 10 hemiparetic human subjects were compared during a sequence of graded voluntary isometric contractions against 4 different-sized loads. These loads were orientated successively at 8 different angles over a 360 degree range, referenced to a plane at the wrist orthogonal to the long axis of the forearm. Comparisons of EMG activity recorded from normal and paretic limbs revealed that there were marked differences in the torque angles which evoked significant EMG activity, in the angular range of EMG, in the angle of peak EMG, and in the scaling of EMG magnitude with increasing isometric loads. In severely impaired limbs, there was a marked shift in both the peak EMG angle and the angular domain of EMG activity for both biceps and triceps muscle groups, away from the normal elbow flexion-extension axis towards external humeral rotation and shoulder girdle elevation. The extent of the disturbance in the spatial patterns of EMG activity was closely correlated with the clinical severity of the spastic-paretic disability, which was quantified using a functional scale patterned after that described by Fugl Meyer et al. (1975). The observed patterns of EMG activity in paretic flexor muscles do not conform with established synergistic patterns, such as might be released by excitation of the flexor reflex in a normal limb. Possible origins for the anomalous EMG patterns are discussed.

Adult↗
PubMed2006

Global patterns reveal strong population structure in Haemonchus contortus, a nematode parasite of domesticated ruminants.

We have examined the global population genetic structure of Haemonchus contortus. The genetic variability was studied using both amplified fragment length polymorphism (AFLP) and nad4 sequences of the mitochondrial genome. To examine the performance and information content of the two different marker systems, comparative assessment of population genetic diversity was undertaken in 19 isolates of H. contortus, a parasitic nematode of small ruminants. A total of 150 individual adult worms representing 14 countries from all inhabited continents were analysed. Altogether 1,429 informative AFLP markers were generated using four different primer combinations. Also, the genetic variation was high, which agrees with results from previous AFLP studies of nematode parasites of livestock. The genetic structure was high, indicating limited gene flow between the different isolates and populations from each continent mostly formed monophyletic groups in the phylogenetic analysis. However, for isolates representing Australia, Greece and one laboratory strain that originated from South Africa (WRS), there was no clear genetic relationship between the isolates and the distance between their geographical origins. Basically the same pattern was observed for the mitochondrial marker, although the phylogenetic analysis was less resolved than for AFLP. In contrast with previous findings on the population genetic structure of H. contortus, the calculation of population structure gave high values (Nst=0.59). The strong structure was present also for the four Swedish isolates (Nst=0.16) representing a small geographical area.

Animals↗
PubMed1997

Reference sera for antinuclear antibodies. II. Further definition of antibody specificities in international antinuclear antibody reference sera by immunofluorescence and western blotting.

OBJECTIVE: To define the fine specificity of the 10 reference sera used for determination of antinuclear antibodies (ANA) and ANA subsets which are available from the Arthritis Foundation (AF) and from the Centers for Disease Control and Prevention (CDC). METHODS: AF/CDC sera were assessed by experienced laboratory staff, using indirect immunofluorescence and Western blotting. RESULTS: The original assignment of fluorescence patterns to 4 reference sera was confirmed, and the fluorescence intensities were determined using reference fluorescent beads. On Western blots, sera AF/CDC2 (anti-SS-B/La) and AF/CDC7 (anti-SS-A/Ro) did not detect Ro antigens, sera AF/CDC9 and AF/CDC10 appeared to be monospecific anti-Scl-70 and anti-Jo-1 sera, respectively, serum AF/CDC4 (anti-U1 small nuclear RNP) recognized the 70-kd band, and serum AF/CDC5 recognized the Sm antigen with its multiple bands. Semiquantitative analyses revealed that AF/CDC5, AF/CDC2, and AF/CDC10 were strongly reactive sera, whereas AF/CDC4 and AF/CDC9 were much weaker and should be used at lower dilutions on Western blots. CONCLUSION: The AF/CDC ANA reference sera, originally described as reference reagents for indirect immunofluorescence and double immunodiffusion techniques, are also useful for Western blotting. The data presented herein further support the use of these sera for reference purposes.

Antibodies, Antinuclear↗