Baseline serum levels of IgA anti-cyclic citrullinated protein antibodies in early rheumatoid arthritis predict radiographic progression after 11 years of treatment: a secondary analysis of the CIMESTRA study

OBJECTIVE

Smoking and periodontitis are risk factors for developing rheumatoid arthritis (RA), suggesting a break of tolerance on mucosal surfaces. Immunoglobulin A (IgA) antibodies are part of the mucosal immune system. The dominant autoantibodies in RA are anti-cyclic citrullinated protein antibodies (ACPAs), and IgG and IgA subclasses exist simultaneously. This study aimed to investigate the association of ACPA IgA subtypes with disease activity and long-term radiographic outcomes in RA, compared with ACPA IgG.

METHOD

Total ACPA IgG, IgA, IgA1, and IgA2 were quantified in serum from patients with early RA (n = 97). Patient characteristics, IgM rheumatoid factor (IgM-RF) status, clinical and biochemical disease activity scores, and radiographic status evaluated by total Sharp score (TSS), were assessed at baseline and after 2 and 11 years of treatment.

RESULTS

All patients with ACPA IgA also had ACPA IgG. ACPA IgA positivity was associated with IgM-RF and male gender. Both ACPA IgA and IgG levels at baseline were weakly associated with disease activity markers. Baseline ACPA IgA and IgG did not show a linear correlation with radiographic status after 10 years, but could predict radiographic progression (ΔTSS ≥ 5 from 0 to 11 years), with positive likelihood ratios of 3.7 and 4.0, respectively.

CONCLUSION

ACPA IgA and IgG were weakly associated with disease activity in early RA. RA patients with a ΔTSS ≥ 5 after 11 years of treatment had higher ACPA IgG and ACPA IgA levels at baseline; however, none of the ACPA subtypes was superior in predicting long-term radiographic progression.

Lymphocyte activation gene 3 is increased and affects cytokine production in rheumatoid arthritis

BACKGROUND

Lymphocyte activation gene-3 (LAG-3) inhibits T cell activation and interferes with the immune response by binding to MHC-II. As antigen presentation is central in rheumatoid arthritis (RA) pathogenesis, we studied aspects of LAG-3 as a serological marker and mediator in the pathogenesis of RA. Since Galectin-3 (Gal-3) is described as an additional binding partner for LAG-3, we also aimed to study the functional importance of this interaction.

METHODS

Plasma levels of soluble (s) LAG-3 were measured in early RA patients (eRA, n = 99) at baseline and after 12 months on a treat-to-target protocol, in self-reportedly healthy controls (HC, n = 32), and in paired plasma and synovial fluid (SF) from chronic RA patients (cRA, n = 38). Peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) were examined for LAG-3 expression by flow cytometry. The binding and functional outcomes of LAG-3 and Gal-3 interaction were assessed with surface plasmon resonance (SPR) and in cell cultures using rh-LAG3, an antagonistic LAG-3 antibody and a Gal-3 inhibitor.

RESULTS

Baseline sLAG-3 in the plasma was increased in eRA compared to HC and remained significantly elevated throughout 12 months of treatment. A high level of sLAG-3 at baseline was associated with the presence of IgM-RF and anti-CCP as well as radiographic progression. In cRA, sLAG-3 was significantly increased in SF compared with plasma, and LAG-3 was primarily expressed by activated T cells in SFMCs compared to PBMCs. Adding recombinant human LAG-3 to RA cell cultures resulted in decreased cytokine secretion, whereas blocking LAG-3 with an antagonistic antibody resulted in increased cytokine secretion. By SPR, we found a dose-dependent binding between LAG-3 and Gal-3. However, inhibiting Gal-3 in cultures did not further change cytokine production.

CONCLUSIONS

sLAG-3 in the plasma and synovial fluid is increased in both early and chronic RA patients, particularly in the inflamed joint. High levels of sLAG-3 are associated with autoantibody seropositivity and radiographic progression in eRA, and LAG-3 plays a biologically active role in cRA by decreasing inflammatory cytokine production. This functional outcome is not affected by Gal-3 interference. Our results suggest that LAG-3 is a faceted regulator of inflammation in early and chronic RA.

Experiences, perspectives, and practice patterns of pulmonary embolism follow-up in Denmark. A mixed method study informing the development of A sTrucTurEd INtegrateD post PE care model

Background

Practice patterns of follow-up after pulmonary embolism (PE) varies both within and between countries, and high-quality evidence to provide clinical guidance is lacking [1,2]. This study is part of the trial – A sTrucTurEd INtegrateD post Pulmonary Embolism care model (Attend-PE) aimed at developing and testing the effectiveness of a structured, integrated and patient-centered follow-up care model for patients with PE.

Purpose

To explore experiences, perspectives, and practice patterns of PE follow-up. Ultimately identifying and describing the opportunity space for a structured integrated post PE care model.

Methods

We performed a convergent mixed method study based on data from patient journey mapping including surveys, observations, and semi-structured patient interviews across all main hospitals treating PE in Denmark. An integrated mixed methods interpretation was conducted using joint displays.

Results

Main results are presented in joint displays in Figure 1 and 2. Observations and surveys were conducted at 18 hospitals including 12 in-depth patient-interviews.

The structure of care varied greatly. Patients expressed a need for early follow up and specialist care but at 18% of the sites first follow-up visit was not until 3–6 months after PE and 24% of the sites only had in-person contact with patients when follow-up echocardiography was needed. At some sites it was also highlighted that not all patients were referred to the post PE follow-up. anticoagulation clinics. Further, transition of care to the general practitioner was identified as a particular challenge.

All sites considered Non-vitamin K antagonist oral anticoagulants the preferred anticoagulant treatment with low-molecular-weight heparins/Vitamin K antagonists as second choice. The possible need for extended treatment and reduced dose favored Rivaroxaban and Apixaban. The decision on treatment duration was most often taken at the 3–6-month follow-up visit, and patients described the decision on extended treatment as positive and reassuring.

Patient information (oral and written) varied greatly and was most often focused on anticoagulant treatment, while knowledge on PE in general, symptom management, and activity was scarce. Two sites offered structured group-based patient education, but unstructured patient education at the individual follow-up visits was most common.

Help and guidance on managing post-PE symptoms and returning to everyday life was perceived essential by patients, as it affected them both physically and mentally. However, none of the sites routinely offered or referred patients to rehabilitation.

Involvement of relatives was considered important but 33% of the hospital sites did not systematically encourage relatives to attend follow-up.

Conclusion

The considerable variation in structure of PE follow-up care demonstrated in this mixed method study highlights the need for a structured integrated post pulmonary embolism care model.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The Danish Heart AssociationThe Novo Nordisk Foundation

Programmed death ligand 2 - A link between inflammation and bone loss in rheumatoid arthritis

Objective

Active rheumatoid arthritis (RA) is accompanied by increased appendicular and axial bone loss, closely associated to the degree of inflammation. The programmed death-1 (PD-1) pathway is important for maintaining peripheral tolerance, and its ligand PD-L2 has recently been associated with bone morphogenetic protein activity. Here, we report that PD-L2 plays a central role in RA osteoimmunology.

Methods

Femoral bone mineral density (BMD) and trabecular bone microstructure were evaluated by micro-CT in wild type (WT) and PD-L2^−/− mice. Osteoclasts were generated from RA synovial fluid mononuclear cells and peripheral blood monocytes. The effects of recombinant PD-L2, was evaluated by tartrate-resistant acid phosphatase (TRAP) activity and the development of bone erosions in the presence of anti-citrullinated protein antibodies (ACPA). Plasma soluble (s)PD-L2 levels were measured in patients with early (e)RA (n ​= ​103) treated with methotrexate alone or in combination with the TNF inhibitor Adalimumab.

Results

PD-L2^−/− mice had a decreased BMD and deteriorated trabecular bone microstructure that was not related to the RANKL/OPG pathway. PD-L2 decreased TRAP activity in osteoclasts and decreased ACPA-induced erosions. In the RA synovial membrane PD-L2 was highly expressed especially in the lining layer and plasma sPD-L2 levels were increased in eRA patients and decreased with treatment. One-year sPD-L2 correlated inversely with erosive progression two years after treatment initiation with methotrexate and placebo.

Conclusion

PD-L2 regulates bone homeostasis in RA. Our findings provide new insight into the relationship between the immune system and bone homeostasis, and suggest a potential therapeutic target for limiting inflammatory bone loss in RA.

•

PD-L2 is closely related to bone homeostasis in a mouse model.

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PD-L2 inhibits osteoclastogenesis and osteoclast activation in vitro.

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PD-L2 is highly expressed by cells in the synovial membrane of rheumatoid arthritis.

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PD-L2 is associated with less radiographic progression in patients with early rheumatoid arthritis.

The DR6 protein from human herpesvirus-6B induces p53-independent cell cycle arrest in G2/M

HHV-6B infection inhibits cell proliferation in G2/M, but no protein has so far been recognized to exert this function. Here we identify the protein product of direct repeat 6, DR6, as an inhibitor of G2/M cell-cycle progression. Transfection of DR6 reduced the total number of cells compared with mock-transfected cells. Lentiviral transduction of DR6 inhibited host cell DNA synthesis in a p53-independent manner, and this inhibition was DR6 dose-dependent. A deletion of 66 amino acids from the N-terminal part of DR6 prevented efficient nuclear translocation and the ability to inhibit DNA synthesis. DR6-induced accumulation of cells in G2/M was accompanied by an enhanced expression of cyclin B1 that accumulated predominantly in the cytoplasm. Pull-down of cyclin B1 brought down pCdk1 with the inactivating phosphorylation at Tyr15. Together, DR6 delays cell cycle with an accumulation of cells in G2/M and thus might be involved in HHV-6B-induced cell-cycle arrest.

Assessing peristomal skin changes in ostomy patients: validation of the Ostomy Skin Tool

BACKGROUND

Peristomal skin problems are common and are treated by a variety of health professionals. Clear and consistent communication among these professionals is therefore particularly important. The Ostomy Skin Tool (OST) is a new assessment instrument for the extent and severity of peristomal skin conditions. Formal tests of reliability and validity are necessary for its use in clinical practice, research, and education.

OBJECTIVES

To estimate inter- and intra nurse assessment variability of the OST and validity by comparison to a 'gold standard' (GS) defined by an expert panel.

METHODS

Thirty photographs of peristomal skin were presented twice to 20 ostomy care nurses--10 from Denmark (DK) and 10 from Spain (ES)--to determine intra- and inter nurse assessment variability. The same photographs were presented to an international group of experts (dermatologist and ostomy care nurses), to establish a GS for comparison and validation of the results.

RESULTS

A high intra-nurse assessment agreement, κ=0·84, was found with no differences in the intra-nurse assessments from the two groups of nurses (DK and ES). The inter-nurse assessment agreement was 'moderate to good', κ=0·54, with the agreement between the experts higher, κ=0·70. A high correlation between the scores from the nurses and the GS were seen in the lower part of the two scales [Discoloration, Erosion, Tissue overgrowth (DET) score<7)].

CONCLUSION

The study supported the validity of the OST. It is suggested that a categorical scale can be used to illustrate the severity of the DET scores.

Effect of red wine and red grape extract on blood lipids, haemostatic factors, and other risk factors for cardiovascular disease

OBJECTIVE

Some epidemiological studies found a lower risk of cardiovascular disease among wine drinkers than among drinkers of other types of ethanol. This difference might be due to an effect of nonalcohol compounds in wine on important cardiovascular risk factors. The objective of this study was to compare the effect of red wine, nonalcohol compounds of red wine and placebo on established cardiovascular risk factors.

DESIGN

A parallel, four-armed intervention study.

SUBJECTS

A total of 69 healthy 38-74-y-old men and women.

INTERVENTIONS

Subjects were randomised to either 1: red wine (males: 300 ml/day, 38.3 g alcohol/day, female subjects: 200 ml/day, 25.5 g alcohol/day), 2: water + red grape extract tablets (wine-equivalent dose), 3: water + red grape extract tablets (half dose), or 4: water + placebo tablets for a period of 4 weeks. No other sources of alcohol or anthocyanin were allowed. Plasma high-density lipoprotein (HDL)-cholesterol (HDL-C), low-density lipoprotein (LDL)-cholesterol (LDL-C), HDL-C/LDL-C-ratio, very-low-density lipoprotein (VLDL)-triacylglycerol, total cholesterol, fibrinogen, factor VII coagulant activity (FVIIc), blood pressure, and body weight were determined before and after intervention.

RESULTS

Wine consumption was associated with a significant 11-16% increase in fasting HDL-C and 8-15% decrease in fasting fibrinogen relative to not drinking wine. There were no significant treatment effects on fasting LDL-C, HDL-C/LDL-C-ratio, VLDL-triacylglycerol, total cholesterol, FVIIc, or blood pressure. Drinking wine was associated with relative body weight increments closely corresponding to the energy contributed by the alcohol component.

CONCLUSION

Moderate red wine consumption for 4 weeks is associated with desirable changes in HDL-C and fibrinogen compared with drinking water with or without red grape extract. The impact of wine on the measured cardiovascular risk factors thus seems primarily explained by an alcohol effect. Our finding suggests that the putative difference in cardiac risk associated with wine vs other alcoholic beverages might be rather explained by other life-style confounders than by red wine contents of nonalcohol components.

Effect of 8 week intake of probiotic milk products on risk factors for cardiovascular diseases

OBJECTIVE

To investigate the effect of a probiotic milk product containing the culture CAUSIDO(R) and of two alternative products on risk factors for cardiovascular disease in overweight and obese subjects.

DESIGN

An 8 week randomized, double-blind, placebo- and compliance-controlled, parallel study.

SUBJECTS

Seventy healthy, weight-stable, overweight and obese (25.0<BMI<37.5 kg/m2) males (n=20) and females (n=50), 18-55 y old, were randomly assigned into five groups.

INTERVENTION

Four groups consumed 450 ml fermented milk products (yoghurt) daily. Group 1: a yoghurt fermented with two strains of Streptococcus thermophilus and two strains of Lactobacillus acidophilus (StLa). Group 2: a placebo yoghurt fermented with delta-acid-lactone (PY). Group 3: a yoghurt fermented with two strains of Streptococcus thermophilus and one strain of Lactobacillus rhamnosus (StLr). Group 4: a yoghurt fermented with one strain of Enterococcus faecium and two strains of Streptococcus thermophilus (CAUSIDO(R) culture), GAIO(R) (G). The dietary composition of the yoghurt was otherwise similar. The fifth group was given two placebo pills (PP) daily.

RESULTS

When comparing all five treatment groups, unadjusted for changes in body weight, no statistical effects were observed in week 8 in the G-group on low density lipoproteins (LDL)-cholesterol (P=0.29). After adjustment for small changes in body weight, LDL-cholesterol decreased by 8.4% (0.26+/-0.10 mmol/l; P<0.05) and fibrinogen increased (0.74+/-0.32 mmol/l; P<0.05) after 8 weeks in the G-group. This was significantly different from the group consuming chemically fermented yoghurt and the group consuming placebo pills (P<0.05). After 8 weeks, systolic blood pressure was significantly more reduced in the StLa and G-group compared to StLr. No other differences were found.

CONCLUSION

The CAUSIDO(R) culture reduced LDL-cholesterol and increased fibrinogen in the overweight subjects at a 450 ml consumption daily for 8 weeks. The effect on LDL-cholesterol confirms previous studies. An immunostimulation by one of the strains in the product might explain the effect on fibrinogen in the G-group.

SPONSORSHIP

MD Foods A/S, Denmark.

A quantitative assay to measure the interaction between immunogenic peptides and purified class I major histocompatibility complex molecules

A direct and sensitive biochemical assay to measure the interaction in solution between peptides and affinity-purified major histocompatibility complex (MHC) class I molecules has been generated. Specific binding reflecting the known class I restriction of cytotoxic T cell responses was obtained. Adding an excess of beta 2-microglobulin (beta 2m) significantly increased the rate of peptide association, but it did not affect the rate of dissociation. Binding was complicated by a rapid and apparently irreversible loss of functional MHC class I at 37 degrees C which might limit the life span of empty MHC class I thereby preventing the inadvertent exchange of peptides at the target cell surface. All class I molecules tested bound peptides of the canonical octa- to nona-meric length. However, one class I molecule, Kk, also bound peptides, which were much longer suggesting that the preference of class I molecules for short epitopes is not absolute and may be caused by factors other than the peptide-MHC class I binding event itself.

The interaction between beta 2-microglobulin (beta 2m) and purified class-I major histocompatibility (MHC) antigen

The function of MHC class-I molecules is to sample peptides from the intracellular environment and present them to CD8+ cytotoxic T lymphocytes. To understand the molecular details of the assembly (and disassembly) of peptide-beta 2m-class-I complexes a biochemical peptide-class-I binding assay has been generated recently and this paper reports on a similar assay for the interaction between beta 2m and class I. As a model system human beta 2m binding to mouse class I was used. The assay is strictly biochemical using purified reagents which interact in solution and complex formation is determined by size separation. It is specific and highly sensitive. The observed affinity of the interaction, KD, is close to 0.4 nM. The rate of association at 37 degrees C is very fast (the ka is around 5 x 10(4)/M/s) whereas the dissociation is slow (the kd is around 8 x 10(-6)/s); the ratio of dissociation to association yields a calculated KD close to the observed value. At 37 degrees C almost all of the purified class I participates in binding of the exogenously offered beta 2m showing that a considerable exchange of the endogenous beta 2m occurs. Finally, it was demonstrated that exogenous beta 2m enhances binding to MHC class-I of short perfectly-matching peptides as well as longer peptides.

A mouse aminopeptidase N is a marker for antigen-presenting cells and appears to be co-expressed with major histocompatibility complex class II molecules

To analyze the expression of mouse aminopeptidase N (APN) on the cells of the immune system a panel of rat monoclonal antibodies against mouse intestinal APN was generated. These antibodies were used to affinity purify functional mouse APN from both intestine and kidney, and by flow cytometry to examine the APN expression of the cells of the mouse immune system. An APN closely related, perhaps identical, to the intestinal APN was expressed on a subpopulation of spleen cells and stimulated peritoneal exudate cells, primarily representing antigen-presenting cells, such as B cells, macrophages, dendritic cells, and veiled cells. In contrast this APN expression could not be detected on thymocytes or spleen T cells. As a corollary, APN was expressed on monocyte, macrophage, and B lymphoma cell lines, but not on T hybridoma or thymoma cell lines. The expression of APN showed a striking correlation with the MHC class II expression in all the cell populations studied. This apparent co-expression suggests a role for APN in antigen processing.

MHC molecules protect T cell epitopes against proteolytic destruction

There is a subtle duality in the role of proteolytic enzymes in Ag processing. They are required to fragment protein Ag ingested by APC. However, prolonged exposure to proteolytic enzymes may lead to a complete degradation of the Ag, leaving nothing for the T cell system to recognize. What ensures that some of the Ag is salvaged? Using a cell-free system we demonstrate that an Ag fragment, once bound to a MHC class II molecule, is effectively protected against proteolytic destruction by cathepsin B and pronase E. The bound fragment, however, can be modified by aminopeptidase N. We suggest that MHC class II molecules play an important regulatory role in the physiologic processing of Ag.

MHC molecules protect T cell epitopes against proteolytic destruction

There is a subtle duality in the role of proteolytic enzymes in Ag processing. They are required to fragment protein Ag ingested by APC. However, prolonged exposure to proteolytic enzymes may lead to a complete degradation of the Ag, leaving nothing for the T cell system to recognize. What ensures that some of the Ag is salvaged? Using a cell-free system we demonstrate that an Ag fragment, once bound to a MHC class II molecule, is effectively protected against proteolytic destruction by cathepsin B and pronase E. The bound fragment, however, can be modified by aminopeptidase N. We suggest that MHC class II molecules play an important regulatory role in the physiologic processing of Ag.

pH dependence of the interaction between immunogenic peptides and MHC class II molecules. Evidence for an acidic intracellular compartment being the organelle of interaction

The pH dependence of the interaction between immunogenic peptide and MHC class II was studied both in a direct biochemical binding assay and in a functional Ag presentation assay. The two approaches yielded similar results. All of the peptides tested bound optimally to their relevant MHC class II restriction element at around pH 4.5. Indeed, several of the peptides did not bind at neutral pH. These results demonstrate that Ag under physiologic conditions meet MHC class II in a quite acidic environment. The very acidic pH optimal for peptide-MHC class II interaction is only found intracellularly and most notably in the endosome-lysosome compartment in which Ag processing is thought to occur. Thus, Ag processing and interaction with MHC class II molecules can potentially happen in the very same compartment. This yet undefined acidic compartment would have to contain proteolytic enzymes and MHC class II molecules.

pH dependence of the interaction between immunogenic peptides and MHC class II molecules. Evidence for an acidic intracellular compartment being the organelle of interaction

The pH dependence of the interaction between immunogenic peptide and MHC class II was studied both in a direct biochemical binding assay and in a functional Ag presentation assay. The two approaches yielded similar results. All of the peptides tested bound optimally to their relevant MHC class II restriction element at around pH 4.5. Indeed, several of the peptides did not bind at neutral pH. These results demonstrate that Ag under physiologic conditions meet MHC class II in a quite acidic environment. The very acidic pH optimal for peptide-MHC class II interaction is only found intracellularly and most notably in the endosome-lysosome compartment in which Ag processing is thought to occur. Thus, Ag processing and interaction with MHC class II molecules can potentially happen in the very same compartment. This yet undefined acidic compartment would have to contain proteolytic enzymes and MHC class II molecules.

Efficacy of HLö-7 and pyrimidoxime as antidotes of nerve agent poisoning in mice

The toxicity and efficacy of two oximes, HLö-7 and pyrimidoxime, were evaluated in mice and compared to those obtained with HI-6. HLö-7 and pyrimidoxime produced 24 h LD50 values of 356 and 291 mg/kg (i.p.), respectively. In combination with atropine (17.4 mg/kg, i.p.), HLö-7 was a very efficient therapy against poisoning by 3 x LD50 dose of soman, sarin and GF and 2 x LD50 dose of tabun with ED50 values of 12.4, 0.31, 0.32 and 25.2 mg/kg, respectively. In contrast, pyrimidoxime was a relatively poor therapy which resulted in ED50 values of greater than 150, 5.88, 100 and 71 mg/kg against poisoning by soman, sarin, GF and tabun, respectively. HLö-7 produced significant (p less than 0.05) reactivation of phosphorylated acetylcholinesterase, in vivo, resulting in 47, 38, 27 and 10% reactivation of sarin, GF, soman and tabun inhibited mouse diaphragm acetylcholinesterase, respectively. HLö-7 also antagonized sarin-induced hypothermia in mice suggesting that it reactivated central acetylcholinesterase. The potential of HLö-7 as a replacement oxime for the treatment of nerve agent poisoning is discussed.

Comparison of several oximes against poisoning by soman, tabun and GF

Three oximes currently being evaluated for adoption as replacement nerve agent therapy by various countries were compared for therapeutic efficacy against the toxic organophosphate inhibitors soman and tabun under a standard set of conditions. These oximes together with PAM-Cl and toxogonin, were also compared for efficacy against GF, an agent weaponized by Iraq. The order of effectiveness against soman was HI-6 greater than HLö-7 greater than pyrimidoxime. HLö-7 was very effective against tabun poisoning while HI-6 and pyrimidoxime were of moderate value. Against GF, HI-6 and HLö-7 were extremely effective, toxogonin was moderately effective, and PAM-Cl and pyrimidoxime were the least effective. HI-6 provided a high level of protection against all of the agents tested as did HLö-7 to a slightly lesser degree. The other oximes suffered from their lack of effects against one or more of the organophosphates.

Toxicity of organophosphate nerve agents and related phosphonylated oximes compared to their anticholinesterase activity in neuron cultures

Oximes, such as pralidoxime and toxogonin, are important therapeutic agents for the treatment of organophosphate (OP) nerve agent poisoning. Oximes can react with these nerve agents to give intermediates, phosphonylated oximes, which may be equally toxic to the parent OP. The sc LD50s of a series of phosphonylated 2-butanone and 2,3-butanedione monoximes were compared to the sc LD50s of their parent OPs (tabun, sarin, and VX) in CD-1 mice. In every case the derivatives were significantly less toxic than their parent nerve agents. Times to death, and to signs of poisoning, were inversely proportional to the dose of test compound, and in all mortalities, blood serum acetylcholinesterase (AChE) was severely inhibited. The relative potencies of these compounds, as well as soman, cyclohexyl methylphosphonofluoridate, and diisopropyl fluorophosphate, as inhibitors of AChE in primary cultures of mouse embryo neurons, correlated with their in vivo toxicities. The results indicate that mouse embryo neuron cultures may be a useful model with which to study this class of compounds.