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Showing papers by "University of Alcalá published in 1998"


Journal ArticleDOI
26 Mar 1998-Nature
TL;DR: Although substance P did not mediate the signalling of acute pain or hyperalgesia, it was essential for the full development of stress-induced analgesia and for an aggressive response to territorial challenge, demonstrating that the peptide plays an unexpected role in the adaptive response to stress.
Abstract: The peptide neurotransmitter substance P modulates sensitivity to pain by activating the neurokinin-1 (NK-1) receptor, which is expressed by discrete populations of neurons throughout the central nervous system. Substance P is synthesized by small-diameter sensory 'pain' fibres, and release of the peptide into the dorsal horn of the spinal cord following intense peripheral stimulation promotes central hyperexcitability and increased sensitivity to pain. However, despite the availability of specific NK-1 antagonists, the function of substance P in the perception of pain remains unclear. Here we investigate the effect of disrupting the gene encoding the NK-1 receptor in mice. We found that the mutant mice were healthy and fertile, but the characteristic amplification ('wind up') and intensity coding of nociceptive reflexes was absent. Although substance P did not mediate the signalling of acute pain or hyperalgesia, it was essential for the full development of stress-induced analgesia and for an aggressive response to territorial challenge, demonstrating that the peptide plays an unexpected role in the adaptive response to stress.

749 citations


Journal ArticleDOI
TL;DR: It is demonstrated that CD36 is a high affinity receptor for the native lipoproteins HDL, LDL, VLDL, and, as previously reported, for OxLDL and AcLDL.

374 citations


Journal ArticleDOI
TL;DR: The results revealed differences between pulp and peel in all cases studied, and high levels of catechins and flavonol glycosides, especially rutin, were found in apple peels.

344 citations


Journal ArticleDOI
TL;DR: In this article, a theoretical model is built to explain the role of migration, labor force participation, and real wage flexibility at the regional level, in determining the degree of persistence of regional relative unemployment.

327 citations


Journal ArticleDOI
Pilar Bustamante1, S. Romero1, Ángeles Peña1, B. Escalera1, A. Reillo1 
TL;DR: The behavior of the apparent thermodynamic magnitudes for the solubility of paracetamol, acetanilide, and nalidixic acid is studied and suggests that the nonlinear enthalpy-entropy compensation effect may be characteristic of the solubsility of semipolar drugs in dioxane-water mixtures.

235 citations


Journal ArticleDOI
15 Apr 1998-Blood
TL;DR: The results show that simultaneous assessment of FSC/SSC and reactivity for the CD117, CD2, CD25, CD33, and CD35 forms the basis for the immunophenotypic characterization of BMMC from SMCD in adults and should be integrated with clinical and morphologic studies for the diagnosis of the disease.

228 citations


Journal ArticleDOI
TL;DR: Several 5-substituted 1,2,3-triazole-TSAO derivatives proved to be potent inhibitors of HIV-1 replication with higher antiviral selectivity than that of the parent TSAO prototype.
Abstract: Several 5-N-alkyl and 5-N,N-dialkylcarbamoyl substituted analogues of the anti-human immunodeficiency virus (HIV) type 1 lead compound[1-[2‘,5’-bis-O-(tert-butyldimethylsilyl)-β-D-ribofuranosyl]-5-...

217 citations


Journal ArticleDOI
TL;DR: A two-part review of the current literature on journal peer review can be found in this paper, where the authors present a survey of the literature on peer review and its applications.
Abstract: This two-part article reviews the current literature on journal peer review. Research on this subject has grown during the 1980s and 1990s, and has increased our awareness of both the myths and fac...

187 citations


Journal ArticleDOI
TL;DR: The possibility that low CSF zinc levels were due to a deficiency of dietary intake seems unlikely, but it is possible that they might be related to the interaction of beta-amyloid and/or amyloid precursor protein with zinc, that could result in a depletion of zinc levels.
Abstract: We compared CSF and serum levels of iron, copper, manganese, and zinc, measured by atomic absorption spectrophotometry, in 26 patients patients with Alzheimer's disease (AD) without major clinical signs of undernutrition, and 28 matched controls. CSF zinc levels were significantly decreased in AD patients as compared with controls (p < 0.05). The serum levels of zinc, and the CSF and serum levels of iron, copper, and manganese, did not differ significantly between AD-patient and control groups. These values were not correlated with age, age at onset, duration of the disease, and scores of the MiniMental State Examination in the AD group. Weight and body mass index were significantly lower in AD patients than in controls. Because serum zinc levels were normal, the possibility that low CSF zinc levels were due to a deficiency of dietary intake seems unlikely. However, it is possible that they might be related to the interaction of beta-amyloid and/or amyloid precursor protein with zinc, that could result in a depletion of zinc levels.

163 citations


Journal ArticleDOI
TL;DR: It is suggested that low CSF zinc concentrations might be related with the risk for Parkinson's disease, although they could berelated with oxidative stress processes.
Abstract: We compared CSF and serum levels of iron, copper, manganese, and zinc, measured by atomic absorption spectrophotometry, in 37 patients with Parkinson's disease (PD) and 37 matched controls. The CSF levels of zinc were significantly decreased in PD patients as compared with controls (p < 0.05). The serum levels of zinc, and the CSF and serum levels of iron, copper, and manganese, did not differ significantly between PD-patient and control groups. There was no influence of antiparkinsonian therapy on CSF levels of none of these transition metals. These values were not correlated with age, age at onset, duration of the disease, scores of the Unified Parkinson Disease Rating Scale of the Hoehn and Yahr staging in the PD group, with the exception of CSF copper levels with the duration of the disease (r = 0.38, p < 0.05). These results suggest that low CSF zinc concentrations might be related with the risk for PD, although they could be related with oxidative stress processes.

140 citations


Journal ArticleDOI
TL;DR: The timing of arrival from spring migration was studied in 4 years for male Pied Flycatchers in central Spain to determine whether arrival times are consistent within individuals between years and are similar between relatives.
Abstract: The timing of arrival from spring migration was studied in 4 years for male Pied Flycatchers (Ficedula hypoleuca) in central Spain. Heritability and repeatability analyses were performed at several levels of familial resemblance and male age in order to determine whether arrival times are consistent within individuals between years and are similar between relatives. Oldest males arrived earlier. Arrival time explained much of the variation in laying time and number of young fledged. Age-independent variation in wing length also affected arrival date, the males with longest wings settling earlier. Arrival times were not repeatable within individuals across years and were not similar between relatives (parents-sons, full-sibs). Although genetic variation may exist in departure dates of long-distance migrant birds, the close connection of an early arrival to high reproductive success may have depleted genetic variation in arrival time. In addition, environmental variation probably is too high to detect significant heritability in arrival times without very large sample sizes.

Journal ArticleDOI
TL;DR: Evidence is provided that a polymerized actin cytoskeleton is required for normal apical growth, hyphal tip shape and polarized enzyme secretion in A. nidulans.
Abstract: Summary: The role of actin in apical growth and enzyme secretion in the filamentous fungus Aspergillus nidulans was studied by treating the hyphae with cytochalasin A (CA), which inhibits actin polymerization. Indirect immunofluorescence microscopy revealed actin at the tips of main hyphae and branches, and at the sites of developing septa. CA inhibited the growth of the fungus and changed the growth pattern of hyphal tips from cylindrical tubes to spherical beads. The regions with swellings showed no actin fluorescence, and neither was actin seen in association with septa. After 4 h exposure, hyphae were able to resume the normal tip growth pattern in the presence of CA for a short period of time and new cylindrical hyphae, with actin fluorescence at the apex, emerged from the swollen tips. Later, the tips of the hyphae swelled again, which led to a beaded apperance. We also studied the effect of CA on the secretion of α- and β-galactosidase. α-Galactosidase is secreted into the culture medium, whereas β-galactosidase remains in the mycelium, with part of its activity bound to the cell wall. When A. nidulans mycelium was incubated in the presence of CA, a reduction in the secretion of α-galactosidase into the culture medium and a decrease in the α- and β-galactosidase activities bound to the cell wall was detected. However, the CA dose used for the hyphae did not modify the secretion of the enzymes from protoplasts. Results described here provide evidence that a polymerized actin cytoskeleton is required for normal apical growth, hyphal tip shape and polarized enzyme secretion in A. nidulans. Cytochalasin-induced disruptions of the actin cytoskeleton could result in the alterations of apical growth and inhibition of enzyme secretion observed by blocking secretory vesicle transport to the apex.

Journal ArticleDOI
TL;DR: A two-part review of the current literature on journal peer review can be found in this paper, where the authors present a survey of both the myths and fact of peer review.
Abstract: This two-part article reviews the current literature on journal peer review. Research on this subject has grown during the 1980s and 1990s and has increased our awareness of both the myths and fact...

Journal ArticleDOI
TL;DR: It is suggested that CD117 in combination with other antigens may be of great help for the identification of leukemia-associated phenotypes that could be used to monitor MRD in both acute myeloid leukemias and multiple myeloma patients achieving morphological complete remission.
Abstract: The c-kit proto-oncogen (CD 117) has been shown to be present in several cell types including normal and neoplastic hemopoietic cells. Among normal BM cells, CD117 expression has been found in about half of the CD34+ precursors including progenitors committed to the erythroid, granulo-monocytic, and megakaryocytic cell lineages. In addition, strong CD117 expression is detected in bone marrow mast cells as well as in a small subset of NK cells displaying strong reactivity for CD56, and in a relatively important proportion of CD3 /CD4 /CD8 prothymocytes. These results suggest that CD117 expression can be detected in both myeloid and lymphoid lineages although for the lymphoid lineage it would be restricted to a small NK-cell subset and early T-cell precursors. In acute leukemias CD117 expression was initially associated with AML. Nevertheless, at present it is well established that CD 117 expression may also be found in a relatively important proportion of T-ALL while it is usually absent in B-lineage ALL. Moreover, recent studies have shown that in about one-third of multiple myeloma cases and patients with monoclonal gammopathy of undetermined significance plasma cells display reactivity for CD1117. The prognostic influence of CD117 expression has not yet been clearly established. The analysis of this marker may also be of value for the investigation of minimal residual disease (MRD). It has been suggested that CD117 in combination with other antigens may be of great help for the identification of leukemia-associated phenotypes that could be used to monitor MRD in both acute myeloid leukemias and multiple myeloma patients achieving morphological complete remission.

Journal ArticleDOI
TL;DR: COMBINE analysis is validated as a powerful methodology for predicting binding affinities and pharmacological activities of congeneric ligands that bind to a common receptor.
Abstract: A comparative binding energy (COMBINE) analysis (Ortiz et al. J. Med. Chem. 1995, 38, 2681−2691) has been performed on a training set of 33 HIV-1 protease inhibitors, and the resulting regression models have been validated using an additional external set of 16 inhibitors. This data set was originally reported by Holloway et al. (J. Med. Chem. 1995, 38, 305−317), who showed the usefulness of molecular mechanics interaction energies for predicting the activity of novel HIV-1 protease inhibitors within the framework of the MM2X force field and linear regression techniques. We first used the AMBER force field on the same set of three-dimensional structures to check up on any possible force-field dependencies. In agreement with the previous findings, the calculated raw ligand−receptor interaction energies were highly correlated with the inhibitory activities (r2 = 0.81), and the linear regression model relating both magnitudes had an acceptable predictive ability both in internal validation tests (q2 = 0.79, ...

Journal ArticleDOI
TL;DR: Intraspecific variability of phenology was found to be low among populations of the same species, and it is hypothesised that type I species possess deeper roots, rely on predictable water sources and occupy mature stages of succession and type II species, on the contrary, are expected to depend on more unpredictable water sources, to possess shallower root systems and to colonise earlier stages ofsuccess.
Abstract: The phenological pattern of fifteen Mediterranean phanaerophytes has been studied in several sites per species, by visiting the populations on a monthly basis over a one year period. Studied phenophases were dolichoblast vegetative growth (DVG), flower bud formation (FBF), flowering (F), fruit setting (FS), seed dispersal (SD), and leaf shedding of dolichoblasts (LSD). Considering the whole set of species, DVG, FBF and F took place mainly in spring, FS in summer, SD in autumn and LSD in summer and in autumn. Interspecific comparisons showed a wide variety of phenological patterns, which have been sorted according to the 'phenophase sequence index' (PSI). This index quantified the degree of superposition between DVG, FBF and F, and it constituted the basis for a functional classification of phenological patterns. Two groups were established. The 'type I' group was characterised by the concentration of phenophases in a short time in spring, while the 'type II' by the protraction and sequential arrangement of phenophases. Type I species performed most of their functions during a resource surplus period, but they have to face an intraplant competition between vegetative and reproductive demands. Type II species avoided intraplant competition but had to develop part of DVG, FBF and F during sub-optimal periods. It is hypothesised that type I species possess deeper roots, rely on predictable water sources and occupy mature stages of succession. Type II species, on the contrary, are expected to depend on more unpredictable water sources, to possess shallower root systems and to colonise earlier stages of succession. Intraspecific variability of phenology was found to be low among populations of the same species. Bud structure, which is a phylogenetic trait, may exert important constraints on plant phenology. Nomenclature: Flora Iberica – Castroviejo et al. 1986–1997, Flora Europaea – Tutin et al. 1964–1980.

Journal ArticleDOI
01 Mar 1998-Methods
TL;DR: Improved knowledge of stacking interactions may lead to a better understanding of the architecture and inherent flexibility of particular DNA sequences and may provide insight into the principles that dictate the structural changes and specificity patterns observed in the binding of some intercalating ligands to DNA.

Journal ArticleDOI
TL;DR: La forte survie des plants du traitement irrigue non ombrage coincidait avec une forte couverture des adventices (Amaranthus retroflexus L.) au cours of the premiere annee.
Abstract: En Europe, de nombreuses terres agricoles ont ete boisees. La politique agricole de l'Union europeenne subventionne actuellement la transformation de terres cultivees en foret avec une attention speciale accordee aux especes feuillues. Pour evaluer les pratiques de boisement, nous avons analyse la croissance et la survie de 800 plants de Quercus ilex sub-espece ballota sur une ancienne terre agricole soumise aux conditions climatiques semi-arides du climat mediterraneen du Centre de l'Espagne. Apres plantation, la survie et la croissance des plants ont ete suivies pendant trois ans. Le dispositif incluait quatre combinaisons : 1) irrigation ou non irrigation pendant la saison seche, 2) ombrage artificiel ou non ombrage. Les traitements ont differe en evapotranspiration potentielle (ETP) (p < 0,0002) et evapotranspiration reelle (ETR) (p < 0,0001). Ces traitements ont induit des differences dans la production d'adventices (p < 0,0001) lesquelles etaient uniquement affectees par l'irrigation. L'irrigation, l'ombrage et l'interaction entre l'irrigation et l'ombrage ont induit un effet positif sur la survie des plants (valeurs-p plus petites que 0,007, 0,0007 et 0,01 respectivement). Les plus grandes differences en terme de survie des plants sont apparues au cours de la fin de la premiere saison seche. La survie ne differait cependant pas de facon significative entre les traitements d'irrigation, d'ombrage et combine. En revanche, chacun des trois traitements ont induit de maniere significative moins de mortalite que le temoin. La forte survie des plants du traitement irrigue non ombrage coincidait avec une forte couverture des adventices (Amaranthus retroflexus L.) au cours de la premiere annee. Des effets significatifs des traitements sur la croissance des plants ont ete notes: p < 0,002 pour le diametre de la tige, et p < 0,0001 pour la hauteur et la surface projetee du houppier (SPH). L'effet de l'ombrage etait significatif pour toutes les mesures de croissance (p < 0,003 diametre de la tige et p < 0,0001 pour la hauteur et la SPH). L'irrigation seule a eu un effet significatif sur le diametre de la tige (p < 0,03) et l'interaction entre l'irrigation et l'ombrage a produit un effet significatif sur la croissance en diametre (p <0,04) et en SPH (p < 0,02). A la fin de la premiere annee, le plus fort diametre correspondait aux parcelles irriguees non ombragees. Toutes les variables mesurees de la croissance etaient correlees avec la quantite d'eau et avec l'ETR (r compris entre 0,35 et 0,78, et valeurs-p entre 0,01 et 0,0001). Les coefficients de correlation etaient plus eleves de 50 % pour la quantite d'eau que pour l'ETR. Nous concluons qu'il faut chercher a reduire le deficit hydrique des plants si l'on veut ameliorer le succes des plantations en terres agricoles dans des milieux secs. L'irrigation des plants pendant l'ete cree des conditions qui permettent la survie des plants apres plantation. En deuxieme et troiseme annee, les traitements d'irrigation et/ou ombrage augmentent la croissance des plants.

Journal ArticleDOI
TL;DR: The rational choice of immobilisation, transduction and biorecognition chemistries is demonstrated in this work to yield improved catalytic and affinity electrochemical biosensors for environmental applications.

Journal ArticleDOI
TL;DR: Continuous somatostatin infusion is as effective as sclerotherapy in preventing early variceal rebleeding and maintaining low mortality following acutevariceal hemorrhage.

Journal ArticleDOI
TL;DR: The formation of adhesions was almost inhibited when the parietal peritoneum was left intact, and in both TS and PS, polypropylene prostheses integrated completely although the composition of the scar tissue was seem to differ; and resistance to traction was similar in bothTS and PS.

Journal ArticleDOI
TL;DR: This study provides a rational basis for estimating the risk of relapse in patients with acute brucellosis, and may be helpful in deciding what subjects might benefit from extra attention.

Journal ArticleDOI
TL;DR: A sequence able to distinguish between the closely related A and D genomes of hexaploid oats is reported, offering new opportunities to analyze the relationships of Avena species and to explore the possible evolution of various polyploid oat species.
Abstract: A satellite DNA sequence, As120a, specific to the A-genome chromosomes in the hexaploid oat, Avena sativa L., was isolated by subcloning a fragment with internal tandem repeats from a plasmid, pAs120, that had been obtained from an Avena strigosa (As genome) genomic library. Southern and in situ hybridization showed that sequences with homology to sequences within pAs120 were dispersed throughout the genome of diploid (A and C genomes), tetraploid (AC genomes), and hexaploid (ACD genomes) Avena species. In contrast, sequences homologous to As120a were found in two A-genome species (A. strigosa and Avena longiglumis) and in the hexaploid A. sativa whereas this sequence was little amplified in the tetraploid Avena murphyi and was absent in the remaining A- and C-genome diploid species. In situ hybridization of pAs120a to hexaploid oat species revealed the distribution of elements of the As120a repeated family over both arms of 14 of 42 chromosomes of this species. By using double in situ hybridization with pAs120a and a C genome-specific probe, three sets of 14 chromosomes were revealed corresponding to the A, C, and D genomes of the hexaploid species. Simultaneous in situ hybridizations with pAs120a and ribosomal probes were used to assign the SAT chromosomes of hexaploid species to their correct genomes. This work reports a sequence able to distinguish between the closely related A and D genomes of hexaploid oats. This sequence offers new opportunities to analyze the relationships of Avena species and to explore the possible evolution of various polyploid oat species.

Journal ArticleDOI
TL;DR: An isolated retrovesical, retroperitoneal or even retrocrural cyst can be the unique manifestation of hydatid disease and although difficult, preoperative diagnosis is desirable for the selection of a surgical approach and prevention of allergic reactions and operative spillage.

Journal ArticleDOI
TL;DR: In this paper, the extension of the Ostrogradski method to relativistic field theories was carried out, and the results strongly support the formal covariant methods used in higher-derivative gravity.
Abstract: We carry out the extension of the Ostrogradski method to relativistic field theories. Higher-derivative Lagrangians reduce to second differential order with one explicit independent field for each degree of freedom. We consider a higher-derivative relativistic theory of a scalar field and validate a powerful order-reducing covariant procedure by a rigorous phase-space analysis. The physical and ghost fields appear explicitly. Our results strongly support the formal covariant methods used in higher-derivative gravity.

Journal ArticleDOI
TL;DR: The presence of a Ureteric stone evokes excitability changes of spinal neurons (enhanced background activity, greater number of ureter-driven cells, decreased threshold of convergent somatic receptive fields), which likely account for the referred hyperalgesia seen in rats with calculosis.
Abstract: Roza, Carolina, Jennifer M. A. Laird, and Fernando Cervero. Spinal mechanisms underlying persistent pain and referred hyperalgesia in rats with an experimental ureteric stone. J. Neurophysiol. 79: 1603–1612, 1998. Spinal neurons processing information from the ureter have been characterized in rats 1–4 days after the implantation of an experimental ureteric stone and compared with those of normal rats. The effects of a conditioning noxious stimulation of the ureter in the presence of the hyperalgesia evoked by the calculosis also were examined. Extracellular recordings were performed at the T12–L1 segments of the spinal cord. In rats with calculosis, more neurons expressed a ureter input (53 vs. 42% in normal rats); such cells being more likely to show background activity, at a higher rate than normals (6.6 ± 1.2 vs. 3.2 ± 0.9 spikes/s; mean ± SE) and increasing with the continuing presence of the stone. The threshold pressure for a ureteric response was higher than in normal rats (79 ± 5 vs. 54 ± 4 mmHg)...

Journal ArticleDOI
TL;DR: The usefulness of the S curve as a strategic analysis tool is discussed as well as the problems that can arise when the model is put into practice.

Journal ArticleDOI
TL;DR: It is suggested that TGF-beta1 may act as a fibrogenic growth factor that could be responsible, at least partially, for the renal interstitial fibrosis associated with aging.
Abstract: In the kidney, aging is characterized by the development of structural changes, including glomerulosclerosis and interstitial fibrosis. Transforming growth factor-beta1 (TGF-beta1) is known to play a critical role in the genesis of these alterations in pathologic conditions. The present experiments were designed to test the hypothesis that TGF-beta1 may be involved in the development of age-related histopathologic changes in rat kidney, and that captopril, an angiotensin-converting enzyme inhibitor, may influence the progression of glomerular and interstitial lesions. In this study, 3-, 18-, 24-, and 30-mo-old rats were examined, and an age-related increase in urinary protein excretion was found; plasma creatinine and systolic BP did not change. Significant structural changes, including glomerular sclerosis and interstitial fibrosis, were found in the group of aged rats (24- and 30-mo-old). Immunostaining for TGF-beta in the renal cortex interstitium was increased in the group of 24-mo-old rats, with a parallel increase in TGF-beta1 mRNA expression, measured with reverse-transcription PCR. Captopril-treated animals showed a statistically significant decrease in urinary protein excretion but no significant changes in BP. Moreover, captopril reduced the extent of interstitial fibrosis, but did not affect the degree of glomerulosclerosis. A significant inhibition of TGF-beta1 mRNA expression was observed in the captopril-treated animals. These findings suggest that TGF-beta1 may act as a fibrogenic growth factor that could be responsible, at least partially, for the renal interstitial fibrosis associated with aging. Treatment with captopril might delay the progression of these lesions.

Journal ArticleDOI
TL;DR: The incidence of HEV in Spain is similar to that in other Western European countries, and HEV is probably not transmitted parenterally to children.
Abstract: Background and Objectives: Hepatitis E virus (HEV) infection usually causes acute self–limited disease. HEV is associated with faecal–contaminated drinking water, but other vectors,

Journal ArticleDOI
TL;DR: The results show that BMMC from both healthy controls and HM patients display a relatively heterogenous immunophenotype, which is similar but heterogenous to bone marrow mast cells from other tissues.
Abstract: The goal of the present paper was to define the immunophenotype of bone marrow mast cells (BMMC) from healthy controls and patients with hematologic malignancies (HM) based on the use of multiple stainings with monoclonal antibodies analyzed by flow cytometry. Our results show that BMMC from both groups of individuals display a similar but heterogeneous immunophenotype. The overall numbers of BMMC are higher in the HM group of individuals (p = 0.08). Three patterns of antigen expression were detected: (1) markers constantly positive in all cases analyzed (CD9, CD29, CD33, CD43, CD44, CD49d, CD49e, CD51, CD71, CD117, and Fc(epsilon)RI), (2) antigens that were constantly negative (CD1a, CD2, CD3, CD5, CD6, CD11a, CD14, CD15, CD16, CD19, CD20, CD21, CD23, CD25, CD30, CD34, CD38, CD41a, CD42b, CD65, CD66b, HLA-DR, and CD138), and (3) markers that were positive in a variable proportion of cases--CD11b (50%), CD11c (77%), CD13 (40%), CD18 (20%), CD22 (68%), CD35 (27%), CD40 (67%), CD54 (88%) and CD61 (40%). In addition, BMMC from all cases explored were CD45+, and this antigen was expressed at an intensity similar to that of mature granulocytes. In summary, our results show that BMMC from both healthy controls and HM patients display a relatively heterogeneous immunophenotype. Interestingly, we have observed clear differences between the immunophenotype of BMMC and MC from other tissues. This could be due either to the heterogeneity of human MC according to their tissue localization or to the sensitivity of the method used for antigen detection.