Ampicillin-sulbactam susceptibility testing criteria

In vitro studies in five different medical centers documented the susceptibility of 2,440 consecutive isolates of theEnterobacteriaceae against ampicillin-sulbactam disks of different potencies. For determination of MICs, both 2:1 or 1:1 ratios were used as long as the concentrations of sulbactam at the breakpoints remained the same, i.e. MIC 16/8.0 µg/ml or 8.0/8.0 µg/ml for the susceptible category. Disks containing 10 µg of ampicillin and 10 µg of sulbactam are still to be preferred with interpretive criteria of 15 mm for susceptible and 11 mm for resistant (MIC 64/32 µg/ml or 32/32 µg/ml). The reliability of the disk test actually diminished when the amount of sulbactam in the disk was increased.     

In vitro activity of saperconazole (R66 905) compared with amphotericin B and itraconazole againstAspergillus species

Twenty isolates of aspergillus were tested against saperconazole and 16 of these against itraconazole and amphotericin B using a macrodilution broth method. For 18 (90 %) of 20isolates tested against saperconazole, MICs were 3.1 mg/l and for 15 (75 %) of 20 isolates MFCs were 3.1 mg/l. For 9 (56 %) of 16 isolates tested against itraconazole, MICs were 3.1 mg/l, and for 4 (33 %) of 12 isolates MFCs were 3.1 mg/l. For all 16 isolates tested against amphotericin B MICs and MFCs were 4.0 mg/l; for 11 of 16 isolates MICs were 2.0 mg/l. Saperconazole appears to be highly active againstAspergillus spp. in vitro, with a bimodal distribution of MICs and MFCs.     

Measurement precision of a portable instrument to assess vibrotactile perception threshold

Summary The objective of the present study was to evaluate the reliability of a modified version of the commercially available Biothesiometer, and to examine vibrotactile perception thresholds with respect to age and gender. A standardized protocol for measuring vibrotactile perception threshold was administered to 80 subjects, once a week over 4 weeks. Inter-session variability was stable (analysis of variance for repeated measures; P>0.05) and correlations were high (Pearson's: 0.87r0.90; P0.001). For sites on both hands and feet, there was a significant increase with age (0.19r ²0.52; P0.001). Five factor analysis of variance model showed that vibrotactile perception threshold was significantly different with stimulus site, age category and gender; no differences were observed with alcohol consumption or smoking status. The findings indicate that the measurements from this device are highly reproducible and sensitive to expected threshold differences with age and gender. The authors attribute this to technical improvements of the original apparatus, rigid adherence to test protocol and maintenance of standard conditions. This type of instrument would be useful in assessing vibrotactile perception loss in occupational health studies.     

The LDL receptor and LRP are receptors for βVLDL on pigeon monocyte-derived macrophages

Receptors for the lipoprotein, beta very low density lipoprotein (VLDL), have been identified through the binding of VLDL-gold conjugates on two ligand-induced regions of pigeon monocyte-derived macrophages. These regions were microvilli/retraction fibers and membrane ruffles. The present study investigated the location and identity of VLDL receptors using an antiserum directed against the epidermal growth factor (EGF) precursor region of the human low density lipoprotein (LDL) receptor. The anti-receptor serum recognized two membrane proteins from pigeon monocyte-derived macrophages, a 116 kDa (LDL receptor) protein and a 600 kDa (low density lipoprotein receptor-related protein; LRP) protein. Ligand blot analysis demonstrated that pigeon VLDL bound to both the LDL receptor and LRP. Immuno-gold electron microscopy using the anti-receptor serum resulted in immunoglobulin localization on the same two ligand-induced regions, microvilli/retraction fibers and membrane ruffles, to which the ligand had bound. Furthermore, simultaneous immunogold localization of the lipoprotein receptor antigens and VLDL-gold (ligand) binding substantiated co-localization of the receptor antigens and VLDL on the ligand-induced regions. Cross-competition studies with the anti-receptor serum and VLDL-gold conjugates documented that increasing concentration of the anti-receptor serum resulted in 70% inhibition of VLDL-gold conjugate binding. These data suggest that pigeon monocyte-derived macrophages utilize both the LDL receptor and LRP as receptors for pigeon VLDL.Supported by grants National Institutes of Health Grants HL-41990, RR-02722 (National Resource for IVEM), HL-14164 (SCOR in Atherosclerosis), and American Heart Association Grant-In-Aid 93006580     

Myofibril and sarcoplasmic reticulum changes with exercise and growth

Summary The intent of this study was to observe the effects of different treadmill running programs upon selected biochemical properties of soleus muscle from young rats. Young 10 day litter-mates were assigned to endurance (E), sprint (S) and control (C) groups. Each was partitioned into either 21 or 51 day exercising groups and 10 day controls. For C the myofibril ATPase activity at 21 and 51 days were lower than 10 day activity (p0.05). In the 51 day E group ATPase activity (0.378±0.009 mol Pi·mg^–1·min^–1) was greater than at 10 and 21 days (0.307±0.006 and 0.323±0.008 mol Pi·mg^–1·min^–1) (p0.05). No change occurred in the S group from 10 to 21 and 51 days (p0.05). Both the 21 and 51 day S (0.318±0.011 and 0.399±0.010 mol Pi·mg^–1·min^–1) and E (0.323±0.008 and 0.378±0.009 mol Pi·mg^–1·min^–1) groups had higher activity compared to the C group (0.193±0.029 and 0.172±0.031 mol Pi·mg^–1·min^–1) (p0.05). Maturation (10–51 day) resulted in a lowered sarcoplasmic reticulum (SR) yield and Ca²⁺ binding (p0.05) while Ca²⁺ uptake ability did not change (p0.05). SR yield, Ca²⁺ binding and uptake were not altered with S training (p0.05). The E training resulted in greater Ca²⁺ uptake at 51 days compared to C and S (p0.05), with no change in Ca²⁺ binding (p0.05). The data suggest that E training alters the normal development pattern of young rat soleus muscle.Supported by grants A-6449 and A-0425 from the Natural Sciences and Engineering Research Council of Canada     

Y-intercept of the maximal work-duration relationship and anaerobic capacity in cyclists

The degree to which the y-intercept (Y-int) of the linear regression of maximal work output on exercise duration represented anaerobic capacity was determined in ten well-trained male cyclists [peak oxygen uptake ( = 69.8 (SD 4.2) ml · kg ^–1 · min ^–1). Each cyclist performed three exhausting cycle sessions on separate occasions; the mean exercise durations were 312, 243 and 141 s for the low (approximately 104% , medium (approximately 108% and high (approximately 113% intensities respectively, and Y-int (kilojoules; joules per kilogram was derived from the regression of work output on exercise duration. The muscle anaerobic adenosine 5-triphosphate (ATP) yield (ATP) and anaerobic capacity (AC) were estimated from changes in metabolites in the vastus lateralis muscle and blood lactate concentration during the high intensity cycling session. The activities of glycogen phosphorylase, phosphofructokinase and citrate synthase, as well as muscle buffer value (in vitro ) were also determined. The Y-int (kilojoules) was positively correlated (P0.05) with AC (r=0.73), ATP (r=0.70) and in vitro (r=0.71); similar correlations (P0.05) were observed for Y-int (joules per kilogram). The Y-int was not correlated (P>0.05) with any enzyme activity. When the Y-int was transformed into oxygen equivalents [litres of oxygen equivalent (1 O₂ Eq)] it was, on average, 0.92 1 O₂ Eq lower than AC (P0.05); however, an alternative method of establishing the work-duration regression yielded a mean Y-int which was only 0.19 1 O₂ Eq less than AC (P0.05). These findings support the validity of Y-int as a work estimate of anaerobic capacity in well-trained cyclists.     

Measurement of urinary Nτ-methylhistamine excretion: Correlation of a newly developed radioimmunoassay (RIA) with gas chromatography mass spectrometry (GCMS)

A newly developed radioimmunoassay (RIA, Y) for the determination of urinary N-methylhistamine concentrations was correlated with gas chromatography mass spectrometry (GCMS, X). In 34 urine samples, with histamine and N-methylhistamine levels within our reference values, the correlation was: Y=1.47X–0.245 mol/l (r=0.92;p-slope 0.0001). In 14 pathological urine samples, derived from patients with mastocytosis and having upper reference values, the correlation was: Y=1.75X–1.02 mol/l (r=0.93;p-slope 0.001). In spite of the greater specificity of the monoclonal antibody for N-methylhistamine compared with that of histamine, relatively high urinary histamine concentrations gave a false positive influence on the RIA results, which was 100% when the histamine/N-methylhistamine ratio was about 19. Clear cases of mastocytosis can be diagnosed, using the RIA-kit, but for a more precise N-methylhistamine value GCMS analyses will remain necessary.     

Biometrical characteristics and physiological responses to a local cold exposure of the extremities

The aim of this study was firstly to describe the physiological responses observed in 19 subjects during immersion of the arm up to the elbow in water at 5 °C (5 min) followed by a 10-min recovery and secondly, to correlate the observed physiological responses with biometrical characteristics of the subjects (maximal oxygen uptake, VO_2max, percentage fat content of whole body, BF, and arm, forearm and hand skinfold thickness). The results showed that the time courses of changes in forearm and hand skin temperature were different compared to those of finger skin temperatures both during local cooling and during rewarming (P < 0.05). Cardiovascular responses (heart rate, systolic and diastolic blood pressures) and finger skin temperatures were not related to the biometrical characteristics of the subjects. However, at the end of the immersion, decreased hand skin temperature was correlated to VO_2max (r = 0.45, P 0.05) whereas decreased forearm skin temperature was correlated both to VO_2max (r = 0.44, P 0.05) and to skinfold thickness (r = –0.44, P 0.05) but not to BF. During the beginning of the recovery period only, outside, inside forearm and hand skin temperatures were related to VO_2max (r = 0.54, P 0.05; r = 0.66, P 0.01 and r = 0.45, P 0.05, respectively) and all the skinfold thicknesses (r = –0.47 to –0.71, P 0.05). It was concluded that the local skin temperature profiles differed according to the upper limb segment both during cooling and during early rewarming. Moreover, VO_2max and upper limb skinfold thickness but not BF did influence the forearm and hand skin temperature changes during cooling and early rewarming but not the finger skin temperature changes and cardiovascular responses.     

Partitioning of Cortical and Deep Cytoskeleton Responses from Transient Magnetic Bead Twisting

We attempted to estimate in living adherent epithelial alveolar cells, the degree of structural and mechanical heterogeneity by considering two individualized cytoskeleton components, i.e., a submembranous cortical cytoskeleton and a deep cytoskeleton (CSK). F-actin structure characterizing each CSK component was visualized from spatial reconstructions at low and high density, respectively, especially in a 10-m-cubic neighborhood including the bead. Specific mechanical properties (Young elastic and viscous modulus E and ) were revealed after partitioning the magnetic twisting cytometry response using a double viscoelastic solid model with asymmetric plastic relaxation. Results show that the cortical CSK response is a faster ( ₁ 0.7s), softer (E₁: 63-109 Pa), moderately viscous (₁: 7-18 Pa s), slightly tensed, and easily damaged structure compared to the deep CSK structure which appears slower (₂ min), stiffer (E₂: 95-204 Pa), highly viscous (₂: 760-1967 Pa s), more tensed, and fully elastic, while exhibiting a larger stress hardening behavior. Adding drug depolymerizing actin filaments decreased predominantly the deep CSK stiffness. By contrast, an agent altering cell–matrix interactions affected essentially the cortical CSK stiffness. We concluded that partitioning the CSK within cortical and deep structures is largely consistent with their respective functional activities. © 2003 Biomedical Engineering Society. PAC2003: 8716Ka, 8716Ac, 8380Lz     

Decreased serum levels of TGF-β in patients with acutePlasmodium falciparum malaria

Apart from cellular immunity and immunopathology, various cytokines have been implicated in malaria-associated immunosuppression. In this study, serum levels of transforming growth factor- (TGF-) were determined with an enzyme-linked immunosorbent assay in 37 patients with acutePlasmodium falciparum malaria prior to, during, and after therapy and in 17 healthy controls in Bangkok, Thailand. Patients were treated with artesunate and mefloquine. TGF- serum levels were found decreased prior to treatment (14±11 pg/ml versus 63±15 pg/ml in healthy controls;P<0.05). The serum concentrations of TGF- increased after initiation of treatment and were within normal range on day 21. Serum levels of both tumor necrosis factor-ga (TNF-) and soluble TNF-receptor 55 kDa were inversely correlated to serum levels of TGF- (r= –0.667 andr=}-0.592, n=37; respectively,P < 0.05 for both). No correlation between parasitemia and serum levels of TGF- could be found. The results are compatible with a decreased production and release, an enhanced clearance or utilization, or tissue accumulation of TGF- in acuteP. falciparum malaria.     

Interpretive criteria and quality control for antimicrobial susceptibility tests of levofloxacin

To confirm preliminary interpretive breakpoints for prototype 5 µg levofloxacin disks, 490 strains were tested in vitro using commercially manufactured disks. For in vitro susceptibility testing, 5 µg levofloxacin disks can be used with interpretive criteria of 12 mm for resistant (MIC 8.0 µg/ml) and 16 mm for susceptible (MIC 2.0 µg/ml). Proposed quality control limits for tests of levofloxacin are as follows:Escherichia coli ATCC 25922, zones 29–37 mm or MIC 0.008–0.03 µg/ml;Pseudomonas aeruginosa ATCC 27853, zones 19–26 mm or MIC 0.5–2.0 µg/ml;Staphylococcus aureus ATCC 25923, zones 24–31 mm;Staphylococcus aureus ATCC 29213, MIC 0.06–0.25 µg/ml andEnterococcus faecalis ATCC 29212, MIC 0.25–2.0 µg/ml.     

Combination therapy of cyclosporine with steroid inhibits γ-interferon and interleukin-1 gene expression at the level of mRNA synthesisin vivo

The present study examined the effect of cyclosporine (CsA) administered with steroidin vivo on the capacity of peripheral blood mononuclear cells (PBMC) from kidney transplant recipients to generate cytokines and their gene expression at the level of messenger RNA (mRNA). PBMC from CsA-prednisolone (Pred)-treated recipients displayed 66.9% inhibition (54.3±12.4 IU/ml;N=42;P<0.01) of -interferon (-IFN) production compared with normal individuals (134.6±18.6 IU/ml;N=23). Azathioprine (Az)-Pred-treated recipients displayed significantly less inhibition of -IFN generation (96.0±16.1 IU/ml;N=22;P<0.05) than CsA-treated patients. Macrophages (m) from CsA-Pred-treated recipients displayed 60.0% inhibition (5.1±0.7 U/ml;N=20;P<0.01) of interleukin-1 (IL-1) production compared with normal individuals (13.0±2.9 U/ml;N=21). These results were confirmed by the experiments using cDNA probe for -IFN or IL-1 (, ). High levels of -IFN mRNA in phytohemagglutinin (PHA)-stimulated PBMC or IL-1() mRNA in lipopolysaccharide (LPS)-stimulated m were present in normal individuals but not in CsA-treated recipients as judged by hybridization to a cloned human -IFN or IL-1() cDNA probe. These studies demonstrated that combination therapy of CsA with steroid inhibits both -IFN and IL-1 gene expression at the level of mRNA at physiological concentrations.     

Comparative in vitro activity of cefdinir (CI-983; FK-482) against staphylococci,gram-negative bacilli and respiratory tract pathogens

The in vitro activity of cefdinir (CI-983; FK-482), a new oral cephalosporin, was compared with that of other antimicrobial agents against clinical isolates of staphylocci, gram-negative bacilli and common respiratory tract pathogens. Cefdinir (MIC90 2.0 µg/ml) was more active than cefixime (MIC90 >64 µg/ml) and equally as active as cefuroxime (MIC90 2.0 µg/ml) against oxacillin-susceptible staphylococci. Cefdinir was active againstHaemophilus influenzae, including -lactamase producers (MIC90 0.5 µg/ml),Moraxella catarrhalis (MIC90 0.12 µg/ml),Streptococcus pneumoniae (MIC90 0.06 µg/ml) andStreptococcus pyogenes (MIC90 0.06 µg/ml). The activity of cefdinir against gram-negative bacilli was variable; organisms with chromosomal cephalosporinases were often resistant.     

Provisional quality control parameters and interpretive criteria for testing susceptibility ofStreptococcus pneumoniae andHaemophilus influenzae to quinupristin/dalfopristin (RP59500)

Studies were undertaken to select tentative criteria for susceptibility testing of quinupristin/dalfopristin againstStreptococcus pneumoniae andHaemophilus influenzae. Against 612 isolates ofStreptococcus pneumoniae, MICs of quinupristin/dalfopristin were 1.0 g/ml for all but one strain. With a tentative MIC breakpoint of either 1.0 g/ml or 2.0 g/ml for susceptible, a disk diffusion zone diameter breakpoint of 19 mm embraced all but two of the susceptible pneumococci; 16 mm included all strains. ForHaemophilus influenzae, MICs of quinupristin/dalfopristin clustered near the tentative breakpoints; 91.5% of the MICs were 2.0 to 8.0 g/ml. This precluded satisfactory performance of the disk diffusion test in discriminating between resistant and susceptible isolates unless MIC breakpoints are modified for this species: clinical experience will be needed before that can be justified. Based on data from a multilaboratory study, the following quality control limits are proposed forStreptococcus pneumoniae ATCC 49619 when testing quinupristin/dalfopristin: 0.25 to 1.0 g/ml for broth microdilution tests and 19 to 24 mm for disk diffusion tests. For tests ofHaemophilus influenzae ATCC 29247, MIC limits are 2.0 to 16 g/ml; disk tests were very reproducible but are not yet recommended.     

Expansion of neopterin and beta2-microglobulin in cerebrospinal fluid reaches maximum levels early and late in the course of human immunodeficiency virus infection

Summary Elevated cerebrospinal fluid (CSF) levels of neopterin and beta₂-microglobulin (\2MG) reflect activation of the cellular immune response in the central nervous system (CNS). In 118 consecutive subjects [15 controls and 103 patients with human immunodeficiency virus (HIV) infection classified according to the Walter Reed staging system (WR)], neopterin and 2MG were determined in paired samples of CSF and serum. The permeability of the blood-CSF barrier and local release of neopterin and 2MG were taken into account: The molecular weight and diameter were used to determine filtration at the blood-CSF barrier. CSF neopterin levels were increased in all stages of HIV infection. 2MG levels were elevated in WR2 and later stages. Neopterin, 2MG, and cell counts similarly showed peaks in WR2, as did neopterin and 2MG also in the later stages WR5 and WR6. Neurologically asymptomatic patients exhibited higher neopterin CSF levels than did controls (12.67 ± 11.6 vs. 2.34 ± 1.05 nmol/l, P < 0.001) and higher CSF 2MG (2.12 ± 1.25 vs. 1.3 ± 0.37 mg/l, P=0.001). Patients with HIV encephalopathy had higher levels of 2MG (3.75 ± 1.83 mg/1) than asymptomatic patients (P < 0.01). CSF levels of neopterin were markedly different in patients with HIV encephalopathy and toxoplasmosis (P < 0.01). A high quantity of local release of the markers neopterin and 2MG may reflect HIV infection of the CNS in early and late stages and additional release upon opportunistic infections.Abbreviations AIDS acquired immunodeficiency syndrome - \2MG beta₂-microglobulin - CNS central nervous system - CSF cerebrospinal fluid - HIV human immunodeficiency virus (type I) - RIA radioimmunoassay - SD standard deviation - SEM standard error of the mean - WR Walter Reed (staging classification) - ELISA enzyme-linked immunosorbent assay     

Metabolic capacity of muscle fibers from high-altitude natives

We evaluate the effects of chronic hypoxia on the metabolic phenotype of the muscle fiber types of humans. The subjects were three Quechua natives residing in the Peruvian Andes at an altitude greater than 3300 m, and three lowlanders from below 700 m. Biopsy specimens were obtained from the vastus lateralis muscles of volunteers. Muscle fibers were identified histochemically as type 1 (oxidative), 2a (oxidativeglycolytic) or 2b (glycolytic). The relative contribution of each fiber type to the total cross-sectional area of each biopsy sample was determined. In individual fibers, the activities of malate dehydrogenase (MDH, citric acid cycle), lactate dehydrogenase (LDH, glycolysis) and adenylokinase (high-energy phosphate) were quantified. The cross-sectional area of the muscle occupied by each fiber type is comparable between Quechuas and lowlanders. Type 1 fibers are the only fiber type to demonstrate statistically significant (P 50.05) differences in enzyme activities between Quechuas and lowlanders. MDH activity is, on average, 19.6% less (P 0.0001) and LDH activity 28.1% more (P 0.0001) in the type 1 fibers of the Quechuas. Chronic hypoxia appears to produce a shift from oxidative to glycolytic metabolism in those fibers which are typically the, most aerobic in human muscle.     

Molecular Characterization of Complement Components (C3, C4, and Factor B) in Human Saliva

A molecular analysis of complement components (C3, C4, and factor B) in human saliva was performed by SDS-PAGE and immunoblotting. Complement C3 was detected as a molecule composed of a 115-kDa -chain linked to a 70-kDa chain by disulfide bonds, and C3 levels ranged from 0.52 to 15.0 /g/ml (n = 15). C4 was detected as a triple-chain molecule (98-kDa chain, 73-kDa chain, and 33-kDa chain) linked by disulfide bonds, and C4 levels ranged from 0.086 to 4.8 g/ml. Factor B was detected as a 100-kDa single chain, and factor B levels ranged from 0.042 to 0.62/g/ml. The sizes and subunit structures of the complement components in human saliva were compatible with those reported in human serum. The results of a hemolytic assay indicated that the complement molecules in human saliva were functionally active. These complement components may participate in the local immune and inflammatory responses in the oral cavity.     

The role ofγδ T cells in the normal and disordered immune system

Summary A small population of T cells does not express the conventional T cell receptor characterized by the and polypeptide chains (TCR) but instead, two polypeptides termed and (TCR). This alternative receptor is able to recognize antigen. It appears early in T cell ontogeny, but its role in the thymus prior to the availability of TCR remains unclear. In selected sites such as skin or gut TCR predominates in mice which might suggest a role of T cells in the first line of defense against infection, T cells secrete lymphokines and display cytotoxic activity. However, their activation requirements may differ from what is known for T cells since MHC-nonrestricted and also CD4 and CD8 negative T cells have been described. Preferential activation by mycobacterial antigens possibly indicates a special repertoire of the T cells. In various diseases slightly increased numbers of T cells were found, but these preliminary studies have not yet provided evidence for a major pathogenetic role of T cells.List of abbreviations C constant region (immunoglobulin or TCR gene segment) - CD4 cluster of differentiation 4 (mainly on helper cells) - CD8 cluster of differentiation 8 (mainly on cytotoxic cells) - D diversity region (immunoglobulin or TCR gene segment) - DNA desoxyribonucleic acid - IL2 interleukin 2 - J joining region (immunoglobulin or TCR gene segment) - kD kiloDalton - MHC major histocompatibility complex - NK natural killer (cells) - RA rheumatoid arthritis - TCR T cell receptor - V variable region (immunoglobulin or TCR gene segment)     

Immunohistochemical studies on S-100 cells in the anterior pituitary gland of Sprague Dawley rats and spontaneous dwarf rats

The S-100 cells in the pituitary glands of adult male Sprague Dawley rats (SDs) and spontaneous dwarf rats (SDRs) were immunohistochemically examined using anti-S-100 and anti-S-100 monoclonal antibodies. The immunoreactive cells against S-100 protein were divided into three subtypes on the basis of their immunore-activity against subunits of S-100 protein: S-100 dominant type (the -type cell), S-100 dominant type (the \-type cell) and immunoreactive against both S-100 and S-100 (the -type cell). In the SD, -type cells represented 26% of the total S-100 immunoreactive cells (S-100 cells) and were localized in the peripheral area of the ventral region of the pituitary gland. This type of cell was observed forming clusters, with more abundant cytoplasm than the -type cell. The proportion of -type cells was 53%. They were diffusely distributed throughout the gland, and their processes were thicker than those of the -type cell. In the SDR, the proportion of -type cells was 55%, and they were observed throughout the gland. In contrast, -type cells totalled 12% and were localized in small areas of the central and peripheral region of the gland. The proportion of -type cells was 21% in the SD and 33% in the SDR and they were observed forming small clusters in both animal groups. The proportion of -type cells compared with the total of S-100-immunoreactive cells was significantly higher (P < 0.05) in the SDR than in the SD, while the proportion of -type cells was markedly lower (P < 0.05).     

Increase in TCRγδ T lymphocytes in synovia from rheumatoid arthritis patients with active synovitis

To determine the relative presence of TCR+ and TCR+ T cells in synovial tissue from patients with various types of inflammatory synovitis and in tissues from patients with a number of chronic T cell-mediated conditions, we stained frozen tissue sections with monoclonal antibodies in indirect immunofluorescence assays. In tissues obtained from patients with chronic T cell-mediated granulomatous conditions (Wegener's granulomatosis, lymphomatoid granulomatosis, granuloma annulare, Langerhan's cells granulomatosis, pigmented villonodular synovitis, Takayasu's arteritis, and talc granulomatosis), the T cells present were predominantly TCR+, without an increased presence of TCR+ cells. In contrast, 6 of 14 (43%) synovia from patients with rheumatoid arthritis (RA) showed increased TCR+ T cells (3–10 cells/hpf). The RA synovia with increased TCR+ cells present had an increased tissue inflammation score compared to RA synovia with few TCR+ cells [18.6±5.8 versus 11.6±4.2 (mean±SE),P<0.05]. In contrast, synovia from patients with osteoarthritis, systemic lupus erythematosus, and trauma did not show an increased presence of TCR+ T cells. Thus, in cellular inflammatory infiltrates the presence of increased TCR cells is not a component of noninfectious granulomatous inflammation but is found in approximately 40% of RA synovia with high levels of inflammation.