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We report the investigations of spin wave modes of arrays of Ni and Co nanorods using Brillouin light scattering. We have revealed the significant influence of spin wave modes along the nanorod axis in contrast to infinite magnetic nanowires. Unusual optical properties featuring an inverted Stokes/anti-Stokes asymmetry of the Brillouin scattering spectra have been observed. The spectrum of spin wave modes in the nanorod array has been calculated and compared with the experiment. Experimental observations are explained in terms of a combined numerical–analytical approach taking into account both the low aspect ratio of individual magnetic nanorods and dipolar magnetic coupling between the nanorods in the array. The optical studies of spin-wave modes in nanorod metamaterials with low aspect ratio nanorods have revealed new magnetic and magneto-optical properties compared to continuous magnetic films or infinite magnetic nanowires. Such magnetic artificial materials are important class of active metamaterials needed for prospective data storage and signal processing applications.

SUMMARY The annual cycle of Lesser Redpolls breeding in Northumberland is described. Birds return in late April and could rear at least two broods, in the absence of predation, before they begin to moult in early August. The complete moult of both sexes usually begins just after the last brood of young reaches independence. Moult ends in late September and the adults then move southwards immediately. Juveniles also finish their partial moult before they migrate, but those which finish moult well before the adults, apparently wait for the latter before undertaking extensive southward movements, though some disperse over short distances in early September. Some adults and juveniles caught during moult at one site returned to moult there in later autumns, even though they did not breed there. Movement in autumn from Britain to the Continent takes place only at the short sea-crossings. More recoveries are obtained abroad in years of poor birch seed crop in southern England. Moult of the remiges and rectrices of the adults is described, and its progress recorded by a numerical scoring system whose merits are discussed. The moult score of the primary feathers follows an approximately linear relationship with date, and the moult scores of all individuals of each sex in each year have been used in regression analyses to yield averages of the duration, start and end of moult, an average daily increase of primary moult score, and the spread of the start of moult within each sample of birds. The results are discussed in relation to breeding and migration. The rates of moult of the primaries, secondaries and tail are not independent of each other, though, in contrast to the primaries, the secondary moult score does not increase linearly with date. The average daily increase of primary moult score is closely correlated with the number of primaries growing simultaneously. Each primary took about 16 days to complete growth in each year, but the duration of moult varied between 43 and 56 days in different years. Variation in the timing and duration of moult of Redpolls in Norway, Iceland and Britain is discussed in relation to the breeding season. Plumage sequences of the Lesser Redpoll are reviewed, with emphasis on their application to separation of sex and age classes. Wing lengths of the males and females of a given age overlap considerably, and abrasion alters these lengths only slightly. Older birds have longer wings. Weight changes of adults and juveniles in autumn are examined in detail. Weight variation of individual birds in August and September is more often due to hourly changes in response to feeding than day-to-day changes in response to temperature. Weights of adults, but not first-year birds, decrease at the start but then increase towards the end of the moult, but apparently there is no deposition of fat for migration. Weights of birds caught during their southward movement also show no increase, nor did a group of Lesser Redpolls caught near Oxford in December. It is suggested that day length may be an additional reason for southward migration, besides a reduction in food supply.

“We must not, I think, deny migration in general: because migration certainly does subsist in certain places, as my brother in Andalusia has fully informed me. Of the motions of these birds he has ocular demonstration”.–Gilbert White, 12 February 1771. Summary 1. Migration was stuaied on the south coast of Spain between Gibraltar and Huelva during five successive springs. Systematic observations were made during a total of 11 weeks by four parties, and casual observations made by other observers have also been used. 2. West of Cape Trafalgar, grounded passerine night migrants were seen in numbers only during east winds. Observations of birds crossing the moon indicated that this correlation was due to drift, and that in the absence of east winds many more birds pass over the Straits of Gibraltar than over the wider stretch of sea to the west, probably after diversion towards the Straits by the west coast of Morocco. 3. The mean heading of nocturnal migrants seen crossing the moon at the Straits of Gibraltar was usually between north and N.N.E., but was N.W. on one night when clouds obscured the stars. 4. Within the periods of east winds, observed migration was correlated with dry weather and rising night temperature in Morocco, but not merely with high temperature. It may also have been correlated with clear skies, but there is slight evidence that cloud cover also caused increased drift. 5. Migration of raptors and storks was seen on most days. Largest numbers were seen at the east end of the Straits in west winds, and vice versa; this is probably due to drift. 6. Other day-migrants seen included Turtle Dove Streptopelia turtur, Bee-eater Merops apiaster, Swift Apus apus, Alpine Swift A. melba, Swallow Hirundo rustica, Sand Martin Riparia riparia, and Short-toed Lark Calandrella cinerea. Many were drifted west of the Straits, retaining their N.E. heading, but others–perhaps those breeding in western Iberia–were seen flying N.W. after crossing the Straits. 7. Large numbers of Black Terns Chlidonias niger were seen flying east or N.E. on a few days of strong east wind.

Summary The nonlinear optical properties of gold nanorod arrays have been studied with a two-colour continuosly working (CW) pump-probe spectroscopy. The hybridization of the nanorod arrays with a nonlinear polymer (poly-3BCMU) has been investigated for the purposes of active photonic component design. The sensitivity of the plasmonic resonances of the hybrid nanostructured system to pump-induced changes in the refractive index of the polymer surroundings has been used to control the optical extinction of the array. Both reversible and non-reversible behaviour has been observed reflecting the combined effects from the third-order nonlinear response of the hybrid metallo-dielectric system and post-photopolymerization triggered reactions in the polymer.

Central nervous system correlates of the visceral hyperalgesia documented in patients with irritable bowel syndrome are limited. Reproducible cerebral evoked potentials can be recorded in response to rhythmic balloon distension of the rectum in healthy adults. Irritable bowel syndrome patients and healthy subjects were studied to compare the characteristics of mechanically-evoked rectal cerebral potentials obtained during fasting and after the ingestion of a standard meal.Twenty-two pairs of age-matched healthy female subjects and female irritable bowel syndrome patients were studied. Cerebral evoked potentials were recorded in response to rhythmic rectal distension (two distension series each of 100 repetitions at 0.8 hertz); cerebral evoked potential recordings were repeated after a 1000 kcal (46% fat) liquid meal. Trait and state anxiety questionnaires were also completed.Compared to healthy subjects, irritable bowel syndrome patients demonstrated higher prevalence of cerebral evoked potential early peaks (latency100 ms) postprandially, and uniformly shorter cerebral evoked potential latencies both before and after feeding.These findings provide further objective evidence for defective visceral afferent transmission in irritable bowel syndrome patients.

Fructose-sorbitol (F-S) mixtures can provoke symptoms in irritable bowel syndrome (IBS) patients, and a proportion of IBS patients also have enteric hypersensitivity to distension. We hypothesized, therefore, that sugar malabsorption and fermentation to produce hydrogen gas may provoke symptoms to a greater extent in IBS patients hypersensitive to distension than in those patients without such hypersensitivity. Our aims were therefore to compare, in IBS patients, symptoms and breath hydrogen responses after F-S, on the basis of jejunal sensitivity and jejunal motor function.Fifteen female IBS patients (44 +/- 15 years) underwent, on separate occasions, 3-h breath hydrogen analyses after ingesting 10 g lactulose and 25 g fructose with 5 g sorbitol. Jejunal sensitivity and motor function were determined by balloon distension and 24-h manometry studies, respectively. Cumulative symptom scores and breath hydrogen production were analysed on the basis of the presence or absence of jejunal hypersensitivity and dysmotility.Four and seven patients had jejunal hypersensitivity for initial perception and pain, respectively. Eleven, nine, and nine patients had jejunal dysmotility for fasting phase 3, phase 2, and fed motor activity, respectively. Of the patients with symptom provocation after F-S (n = 8 within 3 h, n = 12 within 12 h) or with F-S malabsorption (n = 10), the relative proportion did not differ on the basis of the presence or absence of jejunal hypersensitivity or of motor dysfunction. Symptom scores and hydrogen production also were not different in these subgroups.Although carbohydrate malabsorption can provoke symptoms in some IBS patients, there is no consistent association between such a phenomenon and the presence of either jejunal hypersensitivity or dysmotility.

This paper describes an investigation into the dynamic characteristics of a rolling mill. Those characteristics representing limitations, to both productivity and gauge accuracy, are clearly identified with reference to results from a recently installed rolling mill. A linearized mathematical model is developed that conceptually describes these limitations. This model highlights the significance of gauge tension interactions, the second natural frequency of the mill stack dynamic system and the first natural frequency of the entry coil dynamic system.

An increasing demand for HLA-B27 typing as one of the tests used in the diagnosis of ankylosing spondylitis had led us to develop a rapid, automated, flow cytometric assay using whole blood and an HLA-B27 specific monoclonal antibody FD705. This article shows the data from 2093 samples tested during a 2 year period of routine HLA-B27 typing. 21.6% were clearly HLA-B27 positive whilst 73.2% were HLA-B27 negative, the remaining 5.2% required further testing before assignment of HLA-B27 status. Additional work was carried out on blood samples from individuals positive for the newly described subtype HLA-B2708.

Linear and nonlinear magneto-optical properties of the metamaterials based on nickel nanorod assemblies have been studied. The second-harmonic generation properties follow the effective medium description of the metamaterial as a homogeneous layer isotropic in the direction normal to the nanorod axes. Magneto-optical and nonlinear magneto-optical Kerr effects are enhanced in the vicinity of the plasmonic modes of Ni nanorods and of the photonic resonance of the metamaterial layer, while conventional (nonmagnetic) optical response does not exhibit plasmonic-related features. The observed surprisingly high sensitivity of magneto-optical and nonlinear magneto-optical responses to the metamaterial photonic modes is prospective for the diagnostics of plasmonic excitations in magnetic nanostructures and for possible applications in high density magneto-optical data storage.

Europe is currently in a state of flux, not just in political and economic terms, but also with regard to medicine. Changes in the provision of medical care have been common throughout both western and eastern Europe.1 The changes have two main determinants: the need to match limited resources to increasing health care demands, and - especially in central and eastern Europe - the search for new health care philosophies allied to new methods of financing and delivery. Within this process of change, primary medical care is of increasing importance. In many countries hospital based care has traditionally been overvalued and emphasised to the neglect of the appropriate funding and development of primary care. This has led to the inefficient use of both primary and secondary care sectors, often with a lack of proper cooperation and integration. Growing value is placed on the role of the well educated and trained generalist at the primary level. This is clear from developments in the United Kingdom, Holland, Denmark, Sweden, Finland, Spain, and Portugal. From the countries of central and eastern Europe, in which Soviet-style health systems have increasingly failed to meet patients' needs, come numerous requests for information, literature, and expertise on topics such as the principles of primary health care, the role of the family physician, education and training of general practitioners, and the development of the discipline of general practice in both academic and medicopolitical terms. General practice throughout Europe is diverse in its development, organisation, and funding. Some aspects of this diversity can be seen clearly from table I, which shows the numbers of doctors in European countries and the percentage of general practitioners. Table II indicates the considerable variety in consulting patterns by general practitioners throughout the European Union. In spite of this considerable diversity, which has …

SUMMARY HLA-DR/DQ-DP linkage disequilibrium was investigated in healthy, unrelated British (n= 150) and French Canadian (n= 67) caucasoid subjects. HLA-DR and DQ typing was performed by Taq I DNA-RFLP analysis, while DPB1 typing was performed by PCR-SSOP. χ2 and Fisher's exact tests were performed for all 2-locus biallelic comparisons and coefficients of linkage disequilibrium determined. In the British population, only one example of linkage disequilibrium, significant at P= 0.05 (after correction for the number of comparisons made) was seen (DPB1*0101-DRB1*0301[171]). Additional associations, significant at P = 0.05 before correction for the number of comparisons were also seen, including DPB1*0401-DRB1*15, DPB1*1101-DRB1*0701(71), DPB1*1701-DRB1*0701/ 2(72), DPB1*0101-DQA1*0501, DPB1*0401-DQA1*0102, DPB1*0501-DQA1*0102, DPB1*0101-DQB1*0201, DPB1*0401-DQB1*0602/0603 and DPB1*1101-DQB1*0201. With one exception (DPB1*1101-DQB1*0201), none of these associations was seen in the French Canadian group. These results indicate that although more frequent than thought hitherto, HLA class II linkage disequilibrium involving DPB1 alleles is generally weak, and can differ even between different caucasoid populations. This may have implications for HLA and disease studies.

We present an optical sensor based on plasmonic nanorod metamaterials. The sensor operates similar to well-established surface plasmon polariton sensors, but offers order-of-magnitude improvement over existing technology. Optical and biological applications are discussed.

Dynamic magnetic properties of arrays of Ni nanorods with a low aspect ratio have been investigated. It has been shown that the spectra of spin-wave resonances localized on nanorods with a low aspect ratio typically feature the presence of zones with high density of states resulting in a characteristic two-peak pattern of Stokes and anti-Stokes lines of magneto-optical (MO) Brillouin light scattering with pronounced Stokes--anti-Stokes (S-AS) asymmetry. A simple theoretical model based on the analysis of the elliptic character of the polarization of the optical wave interacting with a dipole magnetostatic wave has been proposed. It has been shown that the S-AS asymmetry is due entirely to the asymmetry of the MO interaction efficiency with respect to time reversal of the magnetic precession in a magnon.

Oesophageal intramural pseudodiverticulosis is a rare condition that presents with dysphagia. The diagnosis is usually not apparent endoscopically and careful radiological evaluation is required. Previous reports suggest a benign course with good response of dysphagia to oesophageal dilatation and complications have not been described. Two cases are reported, one in whom life threatening haemorrhage developed following dilatation, and one complicated by a retro-oesophageal collection. It is possible that oesophageal intramural pseudodiverticulosis results in an increased propensity to trauma and even perforation.

We demonstrate that the coupling between plasmonic modes of oriented metallic nanorods results in the formation of an extended (guided) plasmonic mode of the nanorod array. The electromagnetic field distribution associated to this mode is found to be concentrated between the nanorods within the assembly and propagates normally to the nanorod long axes, similar to a photonic mode waveguided by an anisotropic slab. This collective plasmonic mode determines the optical properties of nanorod assemblies and can be tuned in a wide spectral range by changing the nanorod array geometry. This geometry represents a unique opportunity for light guiding applications and manipulation at the nanoscale as well as sensing applications and development of molecular plasmonic devices.

Sperm morphological analysis was performed by 2 methods: light microscopy on Papanicolaou stained material and scanning electron microscopy. Both methods were found to have acceptably low levels of observer error and a positive correlation existed between them. Sperm morphology was analysed by both methods in 2 groups: (1) 104 proven "fertile" men, husbands of women who had just given birth and whose paternity had been proven by HLA studies with greater than 95.5% certainty; (2) 53 infertile men from primary infertile marriages in whom no female cause could be found and excluding those with azoospermia. There was no statistically significant difference in medians between the 2 groups when sperm morphology was analysed by light microscopy, but analysis by scanning electron microscopy did show a significant difference.

The optical properties of metallic nanorod arrays acting as plasmonic nanoantennas have been studied. Large area arrays consisting of bare Au nanorods of diameter and length tuneable in the range of 20--40 and $200--400\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, respectively, and spacing of about $40--100\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ have been electrochemically fabricated using templates of anodized nanoporous aluminium oxide. We demonstrate a very strong sensitivity of their resonant optical properties to both the presence of a dielectric load (which is much smaller than the wavelength of the resonant electromagnetic radiation) and modification of the refractive index of this load. This allows us to finely tune the spectral position of the plasmonic resonance of the nanoantenna arrays throughout the visible spectral range from about $550\phantom{\rule{0.3em}{0ex}}\text{to}\phantom{\rule{0.3em}{0ex}}800\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ with a sensitivity better than $3\phantom{\rule{0.3em}{0ex}}\mathrm{\AA{}}$ per $1\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ thickness of the dielectric load. Such dielectric-loaded plasmonic nanoantenna arrays represent a type of anisotropic metallodielectric metamaterials with fully adjustable optical properties for imaging, sensing, and nonlinear optical applications.

Magneto-dielectric nano-composite (magnetic nanowire in anodic alumina) films are fabricated on silicon substrate. Kerr measurements reveal magnetic properties of the nano-composite, while the microwave measurements in the frequency band 0.2-18 GHz show relatively low dielectric losses. After a proper optimisation these nano- composite films may be used in nonreciprocal and magnetically tuned devices in silicon substrate based Multi-Chip Modules (MCM).

A series of experiments has been undertaken to understand more about the fundamental origin of the thickness-induced permittivity collapse often observed in conventional thin film ferroelectric heterostructures. The various experiments are discussed, highlighting the eventual need to examine permittivity collapse in thin film single crystal material. It has been seen that dielectric collapse is not a direct consequence of reduced size, and neither is it a consequence of unavoidable physics associated with the ferroelectric-electrode boundary. Research on three-dimensional shape-constrained ferroelectrics, emphasizing self-assembled structures based on nanoporous alumina templates and on FIB-milled single crystals, is also presented, and appears to represent an exciting area for ongoing research.

OBJECTIVE--To report multiple cases of recurrent seronegative arthropathy, enthesopathy, or both, occurring in a single family in the absence of the HLA-B27 tissue type, coexistent psoriasis or inflammatory bowel disease. METHODS--Three generations of one family together with their general practitioners completed a standard questionnaire. All subjects with a positive questionnaire and two randomly chosen subjects with negative questionnaires were then examined by a single observer. HLA tissue typing and standard sacroiliac radiographs were performed. RESULTS--Seven of 12 family members with a positive questionnaire had early onset oligo- or polyarthritis, enthesitis, or both, and fulfilled established criteria for spondyloarthropathy, although none had radiological evidence of sacroiliitis. The mean age at first symptom in this group was 22 years with only one individual having the first symptom over the age of 30 years. All subjects were rheumatoid factor negative. Histocompatibility studies showed a strong association with the HLA-B7 antigen. CONCLUSIONS--The observations provide further support for the existence of 9undifferentiated9 spondyloarthropathy and suggest that this can be associated with genetic factors other than HLA-B27.

Internalization signals of the Yxx phi type (phi = bulky hydrophobic side chain) interact with the mu 2 chain of AP-2 adaptors. Internalization activity is intolerant of non-conservative substitution of either the tyrosine or the phi side chains, which bind to hydrophobic pockets in mu 2 adaptin in a conformation described as 'a two pinned plug into a socket'. P-selectin, a type I transmembrane protein, contains the Yxx phi-like sequence YGVF in its cytoplasmic domain, but substitution of either the tyrosine or phenylalanine with alanine in the full-length protein causes only small changes in the rate of endocytosis. It is shown here that the sequence YGVF contained within a peptide corresponding to the 17 COOH-terminal amino acids of P-selectin binds to mu 2 adaptin in the same fashion previously seen for other Yxx phi motifs. In addition, the P-selectin peptide binds to a third hydrophobic pocket in mu 2 adaptin through a leucine at position Y-3 in the peptide. This structure suggests that some sequences can function as a 'three pinned plug', in which internalization activity is not critically dependent on any one of the three interacting side chains.

We report three cases of a rare late complication of neck dissection: anterior dislocation and hypertrophy of the sternal head of the clavicle manifesting as a hard lump in the lower neck. We describe the mode of presentation, etiology, and methods of prevention.

Alterations in both gastric emptying (GE) and small bowel motility have been reported in irritable bowel syndrome (IBS); the relationship, however, between these different measures of upper gut motor function in IBS has not been assessed. The aims of this study were therefore: (1) to compare the prevalence and characteristics of altered small bowel motility in IBS patients with and without delayed GE; and (2) to assess the interrelationships between fasting and postprandial small bowel motility in IBS, accounting for delayed GE. Forty-four IBS patients and 25 healthy controls underwent 24 hr ambulant recording of interdigestive and digestive small bowel motility. On a separate occasion the IBS patients had GE of both solids and liquids measured by a dual-isotope scintigraphic technique. Thirty-nine percent of IBS patients had delayed GE. Patients with normal GE had no interdigestive small bowel abnormalities. However, in patients with delayed GE fasting phase II burst frequency was higher than in controls [median 0.21/hr (IQR 0.15-0.34) vs 0.06/hr (0-0,16), P = 0.004]. Postprandially, abnormal phase III-like activity was higher in diarrhea-predominant IBS patients (0-0.08/hr vs 0/hr, P = 0.01), than in patients with normal GE or controls. Furthermore, IBS patients with delayed GE did not have the normal correlation between fasting and postprandial motor parameters (percentage occurrence of clustered contractions, postprandial pattern duration vs preceding MMC cycle length). In conclusion, small bowel motor dysfunction occurs more frequently in IBS patients with concomitant gastroparesis than in patients with normal GE. These findings provide further evidence that a neuropathic process may contribute to the pathogenesis of IBS in a subgroup of IBS patients.

It remains controversial whether manometric parameters recorded from the pancreatic and biliary segment of the sphincter of Oddi (SO) differ. We therefore studied 48 consecutive patients (40 women, 43 +/- 11 years) with suspected SO dysfunction, in 33 of whom successful dual-duct SO manometry was obtained. Measures of concordance between the two duct segments were moderate for basal sphincter pressure (K = 0.31) and for contractile frequency (0.35), and were low for peak pressure (0.15) and for proportion of retrograde propagation (-0.19). There was also low concordance (-0.13) for the overall manometric diagnosis, and in 48% (CI 31-66%) of patients a conflicting diagnosis (normal/abnormal) was obtained from the two ducts. There was no evidence of a differential motor effect of CCK on either duct, nor were there significant differences in the rate of manometric abnormality according to the order of initial duct cannulation. These results indicate that, if technically feasible, dual-duct manometry of the sphincter of Oddi is required for diagnostic precision.

Postcholecystectomy patients (N = 27) with severe recurrent biliary-like pain who had no evidence of organic disease were subdivided into those with and those without objective evidence of sphincter of Oddi dysfunction (SOD) based on two separate criteria: (1) clinical criteria-elevated liver function tests and/or amylase with pain, and/or a dilated bile duct, and/or delayed drainage at ERCP (N = 14, SOD classes I and II); and (2) abnormal biliary manometry (N = 19). Prolonged (24-48 hr) ambulant recording of duodenojejunal motor activity was performed in all patients and interdigestive small bowel motor activity compared between patient subgroups and a healthy control group. Phase II motor abnormality was more frequent in patients with, compared to those without, objective clinical criteria of SOD (7/14 vs 0/13, P = 0.003). Phase III abnormality also tended to be more frequent in these patients (7/14 vs 2/13, P = 0.06). In addition, both phase III (P = 0.03) and phase II (P = 0.03) motility index (MI) was higher in patients with sphincter dyskinesia compared to controls; phase II MI was also higher in patients with sphincter stenosis (P = 0.005). Disturbances of small bowel interdigestive motor activity are more prevalent in postcholecystectomy patients with, compared to those without, objective evidence of SOD, and especially in patients with SO dyskinesia. Postcholecystectomy SOD in some patients may thus represent a component of a more generalized intestinal motor disorder.

T HE VALUE of the flow cytometric crossmatch (FCXM) has been demonstrated in many centres to be a highly sensitive method for the detection of IgG antibodies in the sera of pretransplant patients that have a significant effect on subsequent renal graft function.’ Since its original description in 1983, many tissue-typing laboratories now perform the FCXM in addition to cytotoxic crossmatching as a method for the selection of a suitable recipient for a transplanted kidney. In the United Kingdom there are currently 20 centres using or intending to use the FCXM for this purpose. As with all clinical assays it is important to study the reproducibility of the FCXM between different centres. Accordingly, over the last 4 years the British Society for Histocompatibility and Immunogenetics (BSHI) Flow Cytometry Special Interest Group has investigated how differences in the method of performing the FCXM techniques may influence the result reported.

The flow cytometric crossmatch is a technique that is increasingly being used by clinical transplant laboratories. In this multicenter study by the British Society for Histocompatibility and Immunogenetics Flow Cytometry Group, a series of crossmatches were carried out to determine whether different centers obtained the same results when performing the same crossmatch. There was greater than 80% agreement among participating laboratories on the results of 34/54 tests. There was no clear agreement in the remaining 20 cases. Quantitative analysis, estimating the number of cell-bound fluorescein molecules, demonstrated that differences in the criteria used by each center to define a positive crossmatch were responsible for some of the discordant results. When applied, definition of positivity based on molecules of fluorescein increased concordance from 57.5% to 81.4%. These results suggest that a criterion for the interpretation of results based on quantitative analysis of bound antibody may be more reliable than methods in current routine use.

The potential for clinical HLA class I A and B typing utilizing the polymerase chain reaction combined with sequence-specific oligonucleotide probes (PCR-SSOP) was investigated. Two hundred and ten clinical samples for the HLA-B locus and 100 clinical samples for the HLA-A locus were typed by DNA-based methods and serology. For the HLA-B locus an improved SSOP typing system was developed which involved using HLA-B specific 5′ primers and two 3′ primers, in separate reactions. Using a panel of 30 digoxigenin-labelled SSOPs, HLAB types were assigned for all 210 individuals with an improvement in resolution over previously described DNA-based systems and confirming serologically assigned types in all cases except one. In addition, using a single primer pair and a panel of 16 SSOPs, 100 samples were successfully HLA-A typed by PCRSSOP resolving ambiguous serological types, including HLA-A19 subtypes and A2 homozygosity. In 25 samples, the assigned types were also confirmed by the amplification refractory mutation system (ARMSPCR). These results indicate that non-urgent clinical HLA-A and -B typing may be performed by PCRSSOP with a resolution at least equal to that of serology.

The potential for clinical HLA class I A and B typing utilizing the polymerase chain reaction combined with sequence-specific oligonucleotide probes (PCR-SSOP) was investigated. Two hundred and ten clinical samples for the HLA-B locus and 100 clinical samples for the HLA-A locus were typed by DNA-based methods and serology. For the HLA-B locus an improved SSOP typing system was developed which involved using HLA-B specific 5' primers and two 3' primers, in separate reactions. Using a panel of 30 digoxigenin-labelled SSOPs, HLA-B types were assigned for all 210 individuals with an improvement in resolution over previously described DNA-based systems and confirming serologically assigned types in all cases except one. In addition, using a single primer pair and a panel of 16 SSOPs, 100 samples were successfully HLA-A typed by PCR-SSOP resolving ambiguous serological types, including HLA-A19 subtypes and A2 homozygosity. In 25 samples, the assigned types were also confirmed by the amplification refractory mutation system (ARMS-PCR). These results indicate that non-urgent clinical HLA-A and -B typing may be performed by PCR-SSOP with a resolution at least equal to that of serology.

Tissue typing can help in the diagnosis of the seronegative arthropathy ankylosing spondylitis. Using an automatic sample preparation system and flow cytometry (FACSPrep/FACScan) we have developed a test for HLA-B27 screening using whole blood which is both rapid, reproducible, and permits simultaneous screening of large numbers of samples. We have used both indirect (248 cases) and direct (126 cases) monoclonal antibody staining techniques. Results were assessed using median channel shift (CS) from the negative control and relative fluorescence intensity. There is known cross-reactivity between HLA-B27 and HLA-B7 with the monoclonal antibody (MoAb) HLA-ABC-m3. Using this antibody and indirect staining, HLA-B7 samples had a significantly lower CS value than HLA-B27 samples. In 60% of these cases there was a clear distinction between HLA-B27 and HLA-B7. All HLA-B27 and HLA-B7 negative samples had a CS of 0 (P < 0.001). Using direct dual staining with CD3 and HLA-B27, all HLA-B7 negative samples had a low CS value (15 maximum), HLA-B7 samples had an intermediate CS value (20–85), and HLA-B27 samples had the highest CS values (70 upward). This system permits large scale rapid negative screening of samples with the elimination of over 60% as negatives (CS < 15). Limitations as a definitive test for HLA-B27 are due to MoAb cross-reactivity with HLA-B7 which necessitates other confirmatory techniques. The substitution of the HLA-ABC-m3 with the recently available HLA-B27 specific MoAb FD705 would substantially increase the value of this technique for routine HLA-B27 typing. © 1994 Wiley-Liss, Inc.