Lactobacillus rhamnosus CNCM I-3690 and the commensal bacterium Faecalibacterium prausnitzii A2-165 exhibit similar protective effects to induced barrier hyper-permeability in mice

Impaired gut barrier function has been reported in a wide range of diseases and syndromes and in some functional gastrointestinal disorders. In addition, there is increasing evidence that suggests the gut microbiota tightly regulates gut barrier function and recent studies demonstrate that probiotic bacteria can enhance barrier integrity. Here, we aimed to investigate the effects of Lactobacillus rhamnosus CNCM I-3690 on intestinal barrier function. In vitro results using a Caco-2 monolayer cells stimulated with TNF-α confirmed the anti-inflammatory nature of the strain CNCM I-3690 and pointed out a putative role for the protection of the epithelial function. Next, we tested the protective effects of L. rhamnosus CNCM I-3690 in a mouse model of increased colonic permeability. Most importantly, we compared its performance to that of the well-known beneficial human commensal bacterium Faecalibacterium prauznitzii A2-165. Increased colonic permeability was normalized by both strains to a similar degree. Modulation of apical tight junction proteins expression was then analyzed to decipher the mechanism underlying this effect. We showed that CNCM I-3690 partially restored the function of the intestinal barrier and increased the levels of tight junction proteins Occludin and E-cadherin. The results indicate L. rhamnosus CNCM I-3690 is as effective as the commensal anti-inflammatory bacterium F. prausnitzii to treat functional barrier abnormalities.

Preliminary design of laser-induced breakdown spectroscopy for proto-Material Plasma Exposure eXperiment

Laser-induced breakdown spectroscopy (LIBS) is a technique for measuring surface matter composition. LIBS is performed by focusing laser radiation onto a target surface, ablating the surface, forming a plasma, and analyzing the light produced. LIBS surface analysis is a possible diagnostic for characterizing plasma-facing materials in ITER. Oak Ridge National Laboratory has enabled the initial installation of a laser-induced breakdown spectroscopy diagnostic on the prototype Material-Plasma Exposure eXperiment (Proto-MPEX), which strives to mimic the conditions found at the surface of the ITER divertor. This paper will discuss the LIBS implementation on Proto-MPEX, preliminary design of the fiber optic LIBS collection probe, and the expected results.

Design of a real-time two-color interferometer for MAST Upgrade

A single chord two-color CO2/HeNe (10.6/0.633 μm) heterodyne laser interferometer has been designed to measure the line integral electron density along the mid-plane of the MAST Upgrade tokamak, with a typical error of 1 × 10(18) m(-3) (∼2° phase error) at 4 MHz temporal resolution. To ensure this diagnostic system can be restored from any failures without stopping MAST Upgrade operations, it has been located outside of the machine area. The final design and initial testing of this system, including details of the optics, vibration isolation, and a novel phase detection scheme are discussed in this paper.

Conceptual design of a neutron camera for MAST Upgrade

This paper presents two different conceptual designs of neutron cameras for Mega Ampere Spherical Tokamak (MAST) Upgrade. The first one consists of two horizontal cameras, one equatorial and one vertically down-shifted by 65 cm. The second design, viewing the plasma in a poloidal section, also consists of two cameras, one radial and the other one with a diagonal view. Design parameters for the different cameras were selected on the basis of neutron transport calculations and on a set of target measurement requirements taking into account the predicted neutron emissivities in the different MAST Upgrade operating scenarios. Based on a comparison of the cameras' profile resolving power, the horizontal cameras are suggested as the best option.

Evaluation of the utility of subjective clinical parameters for estimating fecal egg counts and packed cell volume in Canadian sheep flocks

A study was conducted in sheep on Canadian farms to describe the relationship between packed cell volume (PCV) or fecal egg counts (FEC) and subjective clinical parameters that may indicate the severity of parasitic gastroenteritis. Twenty-one farms in Ontario (ON) and 8 farms in Quebec (QC) were purposively selected and visited during April-May (spring) and August (summer) 2007. At each farm visit, blood and fecal samples were collected from 10 ewes and 10 female lambs; body condition score (BCS), dag score (DS), fecal consistency score (FCS) and FAMACHA score were recorded for all sampled sheep. Packed cell volume was determined for all blood samples, and FEC were performed for all fecal samples. Summary statistics and simple correlations were performed for the parameters recorded. Two mixed models with random effects at the farm level were developed; one using PCV as the response variable and another using the natural log of eggs per gram of feces (lnEPG). Finally, the residuals from both models were correlated to the covariates in the models. The mean PCV values during the spring were 29.7% and 36.7% for lambs, and 28.8% and 31.1% for ewes, in ON and QC, respectively. During the summer, the mean PCV was 32.0% and 32.8% for lambs, and 30.1% and 29.9% for ewes, in ON and QC, respectively. The arithmetic mean FEC per gram of feces (EPG) during the spring was 3 and 2 for lambs, and 1266 and 789 for ewes, in ON and QC, respectively, whereas during summer the arithmetic mean EPG was 907 and 237 for lambs, and 458 and 246 for ewes, in ON and QC, respectively. Results from simple correlations indicated that PCV was negatively correlated with lnEPG (r = -0.255; r(2) = 6.5%) and FAMACHA (r = -0.312; r(2) = 9.7%), and positively correlated with BCS (r = 0.317; r(2) = 10%). LnEPG was negatively correlated with BCS (r = -0.232; r(2) = 5.4%) and PCV (r = -0.255; r(2) = 6.5%), but positively correlated with FAMACHA (r = 0.178; r(2) = 3.2%) and DS (r = 0.086; r(2) = 0.7%). Results from the models indicated that PCV and lnEPG residuals were negatively correlated with FAMACHA, FCS and almost all categories of BCS and DS, although the correlations were very low. The main results from this study suggested that none of the subjective clinical parameters evaluated were highly correlated with PCV or lnEPG and therefore were not good predictors of lnEPG or PCV on the studied farms in Ontario and Quebec.

[Patellofemoral pain syndrome: understand better in order to treat better]

Patellofemoral pain syndrome (PFPS) is one of the most frequent cause of anterior knee pain in adolescents and adults. Due to its complex etiology, which is multifactorial and still poorly understood, its management is a major challenge for the practitioner. The diagnosis is made primarily on the history and clinical examination of the knee, but also of the entire lower limb, which may sometimes require the completion of imaging. The treatment is mostly conservative, focussing on rehabilitation with targeted and personalized therapy. Surgical treatment is reserved for cases with a causal structural lesion.

Crystal and Molecular Structure of Bis(N,N,N′,N′ -tetramethyl-1,4-diaminobenzeniumyl) [Wurster s Blue Cation]-tetracyanoplatinate(II)-mono-hydrate

The title compound crystallizes in the monoclinic space group A 2/m (C2h 3) with a = 10.61(3) Å, b = 9.511(5) Å and c = 16.47(5) Å, β = 124.2(1)° and two formula units in the unit cell. The structure was solved by Patterson and Fourier methods and refined by least squares to R = 0.071 based on 1251 observed intensities. The organic cations are slightly distorted and are arranged in dimers along the crystallographic a-axis. There are “mixed stacks” of the planar [Pt(CN)4]2− units which are separated from each other by the WB2 2+ dimers along b. There is IR-evidence for the formation of hydrogen bridges between [Pt(CN)4]2− units and the crystal water during the modification change of the compound at room temperature.

Structure of a Pt(II)-Pt(IY) Mixed-Valence Linear Chain Complex: Bis (1,2-diaminopropane )platinum(II)bis (1,2-diaminepropane ) - dibromoplatinum(IV)tetraperchlorate

[Pt(C3H10N2)2][Pt(C3H10N2)2Br2](ClO4)4 crystallizes as flat orthorhombic needles with cell dimensions: a = 7.74(1); b = 11.14(2); c = 19.42(3) Å, Z = 1. Since rotation photo­graphs showed diffuse patterns corresponding to odd values of k without any Bragg reflections, the subcell for which b = 5.57(1) Å was adopted for the structural analysis; it has systematic absences consistent with space groups Pc 2 a and Pcma; the structure was refined in both space groups by least squares and difference Fourier syntheses to R = 0.062 in Pc 2a and R = 0.064 in Pcma. A final decision between the two space groups proved to be impossible within the scope of the experiment. An analysis of the “diffuse” layers reveals that the bridging bromines vibrate in a one-dimensional collective mode within a lattice of “uniform”, fixed platinum cations.

Structure of Dibromo(1,2-diaminoethane)palladium(IV)-bis(1,2-diaminoethane)- palladium(II) Tetrakisperchlorate, [Pd(en)2Br2][Pd(en)2](ClO4)4

Orthorhombic [Pd(C2H8N2)2Br2][Pd(C2H8N2)][ClO4]4, C8H32Br2Cl4N8O16Pd2, Mr = 890.42, crystallizes in space group Iba2, a = 9.651(2), b = 13.951(8), c = 10.771(2) Å, Z = 2, V = 1412.80 Å3, dc = 2.05 g cm-3, R = 0.0564 for 1545 unique reflections. Data collection: MoKα, λ = 0.71069 Å, room temperature.

The structure is a typical Wolffram’s Salt Analogue (WSA) with infinite stacks of planar [Pd(en)2]2+,4+ complex cations bridged by bromides. The ligands are three-dimensionally ordered. Intra-chain and inter-chain hydrogen bridges link the ligands with the perchlorate counter ions which occupy statistically two different orientations. Diffuse sheets appear together with Bragg reflections for 1 odd layers indicating a thermally activated motion of the bromides in chain direction. This model was confirmed with temperature dependent Weissenberg work

Kristall- und Molekülstruktur eines „linearen“ Festkörpers mit drei verschiedenen Metallsträngen: [Pt(dapn)2] [Pt(dapn)2Br2] [(Cu3Br5)2] (dapn = 1.2-Diaminopropan)/Crystal and Molecular Structure of a Linear Chain Solid with Three Different Metal Chains: [Pt(dapn)2][Pt(dapn)2Br2][(Cu3Br5)2] (dapn = 1,2-diaminopropane)

The compound {[Pt(dapn)2][Pt(dapn)2Br2]}(Cu3Br5)2, which was prepared by oxidation of Pt(dapn)2Br2 with CuBr2, crystallizes in the orthorhombic space group Bmmb (D2h 17), a = 5.617(4) Å, b = 16.206(6) Å, c = 22.00(1) Å, Z = 2. The experimentally determined density is 3.22 g · cm-3 (calculated 3.40). The structure has been determined by Patterson and Fourier methods from single crystal diffractometer data and refined by least squares to R = 0.085 for 485 independent reflections. Crystals of the title compound contain halide-bridged copper and platinum chains.

Crystal and Molecular Structure of the Linear Chain Bis(1,2-diaminopropane)platinum(II,IV)tribromide

[Pt(dapn)2]Br3 (dapn = 1,2-diaminopropane), ortho-rhombic, Immm (D25 2h), a = 5.338(1), b = 6.900(5), c= 19.738(4) Å, Z = 2, V= 727 Å3 , dc = 2.7 g · cm-3 . The structure was refined to R = 0.094 for 576 reflections and can be described as a Wolffram's salt analogue. A rotating crystal photograph shows weak diffuse layers between the Bragg reflections as evidence for one-dimensional order along the M-X-M chain, but for successful refinement the M-X distance (2.673(1) Å) have to be assumed to be equal.

Rare Eugenol-and Z-Coniferyl Alcohol Derivatives in Roots of Three Coreopsis Species

Roots of three species of the genus Coreopsis (Compositae), C. tinctoria, C. lanceolata and C. grandiflora were investigated for the occurrence of phenylpropanoids. In addition to phenylpropanoids already known from other Coreopsis species some new derivatives of eugenol- and Z-coniferyl alcohol were found. In this report we present their structures together with their 1H NMR. 13C NMR and MS data. Two aromatic acetylenes - one of them not previously described for Coreopsis species - were identified as well.

Efficacy of Bifidobacterium breve NCC2950 against DSS-induced colitis is dependent on bacterial preparation and timing of administration

Probiotics have been proposed as a therapy for inflammatory bowel disease, but variations in strains, formulations, and protocols used in clinical trials have hindered the creation of guidelines for their use. Thus, preclinical insight into the mechanisms of specific probiotic strains and mode of administration would be useful to guide future clinical trial design. In this study, live, heat inactivated (HI), and spent culture medium preparations of the probiotic Bifidobacterium breve NCC2950 were administered to specific pathogen free C57BL/6 mice before or during colitis, as well as before colitis reactivation. Five days of 3.5% dextran sulphate sodium in drinking water was used to induce colitis. Pretreatment with live B. breve reduced disease severity, myeloperoxidase activity, microscopic damage, cytokine production, interleukin (IL)-12/IL-10 ratio, and lymphocyte infiltration in the colon. B. breve did not attenuate on-going colitis. After acute colitis, disease symptoms were normalised sooner with live and HI B. breve treatment; however, reactivation of colitis was not prevented. These findings indicate that the efficacy of a probiotic to modulate intestinal inflammation is dependent on the formulation as well as state of inflammation when administered. Overall, live B. breve was most efficacious in preventing acute colitis. Live and HI B. breve also promoted recovery from diarrhoea and colon bleeding after a bout of acute colitis.

Negative pressure wound therapy for managementof the surgical incision in orthopaedic surgery: A review of evidence and mechanisms for an emerging indication

Objectives

The period of post-operative treatment before surgical wounds are completely closed remains a key window, during which one can apply new technologies that can minimise complications. One such technology is the use of negative pressure wound therapy to manage and accelerate healing of the closed incisional wound (incisional NPWT).

Methods

We undertook a literature review of this emerging indication to identify evidence within orthopaedic surgery and other surgical disciplines. Literature that supports our current understanding of the mechanisms of action was also reviewed in detail.

Results

A total of 33 publications were identified, including nine clinical study reports from orthopaedic surgery; four from cardiothoracic surgery and 12 from studies in abdominal, plastic and vascular disciplines. Most papers (26 of 33) had been published within the past three years. Thus far two randomised controlled trials – one in orthopaedic and one in cardiothoracic surgery – show evidence of reduced incidence of wound healing complications after between three and five days of post-operative NPWT of two- and four-fold, respectively. Investigations show that reduction in haematoma and seroma, accelerated wound healing and increased clearance of oedema are significant mechanisms of action.

Conclusions

There is a rapidly emerging literature on the effect of NPWT on the closed incision. Initiated and confirmed first with a randomised controlled trial in orthopaedic trauma surgery, studies in abdominal, plastic and vascular surgery with high rates of complications have been reported recently. The evidence from single-use NPWT devices is accumulating. There are no large randomised studies yet in reconstructive joint replacement.

Cite this article: Bone Joint Res 2013;2:276–84.

Disentangling coordination among functional traits using an individual-centred model: impact on plant performance at intra- and inter-specific levels

Background

Plant functional traits co-vary along strategy spectra, thereby defining trade-offs for resource acquisition and utilization amongst other processes. A main objective of plant ecology is to quantify the correlations among traits and ask why some of them are sufficiently closely coordinated to form a single axis of functional specialization. However, due to trait co-variations in nature, it is difficult to propose a mechanistic and causal explanation for the origin of trade-offs among traits observed at both intra- and inter-specific level.

Methodology/Principal Findings

Using the Gemini individual-centered model which coordinates physiological and morphological processes, we investigated with 12 grass species the consequences of deliberately decoupling variation of leaf traits (specific leaf area, leaf lifespan) and plant stature (height and tiller number) on plant growth and phenotypic variability. For all species under both high and low N supplies, simulated trait values maximizing plant growth in monocultures matched observed trait values. Moreover, at the intraspecific level, plastic trait responses to N addition predicted by the model were in close agreement with observed trait responses. In a 4D trait space, our modeling approach highlighted that the unique trait combination maximizing plant growth under a given environmental condition was determined by a coordination of leaf, root and whole plant processes that tended to co-limit the acquisition and use of carbon and of nitrogen.

Conclusion/Significance

Our study provides a mechanistic explanation for the origin of trade-offs between plant functional traits and further predicts plasticity in plant traits in response to environmental changes. In a multidimensional trait space, regions occupied by current plant species can therefore be viewed as adaptive corridors where trait combinations minimize allometric and physiological constraints from the organ to the whole plant levels. The regions outside this corridor are empty because of inferior plant performance.

Impact of hepatectomy margin on survival following resection of colorectal metastasis: the role of adjuvant therapy and its effects

INTRODUCTION

The optimal width of microscopic margin and the use of adjuvant therapy after a positive margin for hepatic resection for colorectal liver metastasis (CRCLM) has not been conclusively determined. The aim of the current study is to evaluate the influence of width of surgical margin and adjunctive therapy upon disease free and overall survival.

METHODS

All patients undergoing hepatectomy for CRCLM from 1997 to 2012 were identified from a prospectively maintained, IRB approved database. Patients were divided into four subgroups based on the parenchymal margin: positive, <0.1 cm, 0.1 cm-1 cm, and >1 cm.

RESULTS

A total of 373 patients were included for analysis with a median follow up of 26 months (range 9-103 months) and a median overall survival of 53 months. The resection margin was positive (26 patients median OS 24 months), <0.1 cm (48 patients median OS 36 mon), 0.1 cm-1 cm (82 patients median OS 44 months), and >1 cm (217 patients median OS 64 months). The most common adjunctive therapy was chemotherapy, hepatic arterial therapy, or local. Patients with positive margins also had the shortest disease free survival (DFS), 16 months. The DFS was similar amongst the other margin groups (<0.1 cm: 21 months, 0.1-1 cm: 22 months, >1 cm 25 months). Hepatectomy margin independently influenced survival (p = 0.017) and disease free survival (p = 0.034). Patients with negative margins has similar overall recurrence rates (p = 0.36) and survival rates (p = 0.89).

CONCLUSIONS

A positive surgical margin indicates a worse overall biology of disease for patients undergoing hepatectomy for CRCLM, and appropriate multi-disciplinary therapy should be considered in this high risk patient population. Marginal width if a complete resection has been achieved does not adversely effect overall surgical in patients with CRCLM.

[Return to sport after anterior cruciate ligament reconstruction]

Despite continuous advances in techniques for anterior cruciate ligament reconstruction (ACLR), return to play (RTP) after surgery remains a challenge. More than one-third of the patients are unable to return to their preinjury sport level, for most because of a fear to sustain another injury. And when a RTP is attempted, up to 20% will tear their graft and a similar % will sustain an ACL tear on the opposite side. We believe that these failures result from an incomplete recovery. Based on a literature review and on our experience, we suggest 6 objective criteria to allow a safer RTP. They rely on laxity, strength, neuromuscular function, and psychological evaluations. Rehabilitation after ACLR should focus on the deficits identified by these tests and on they specific needs of the sport that the athlete plans to return to.

[Hyperspectral imaging in head & neck oncology]

Hyperspectral Imaging has long been established in other scientific disciplines than medicine (e. g. earth science) as a means for objective classification of image data information. Some 10 years ago it was first introduced into medicine. Due to its immanent advantages - non-destructive specimen, compatibility with established optical tools (microscope, endoscope), objectivity, and user-independence - several attempts have been made in order to use its potential for the treatment of cancer patients. This publication reviews which methods have been developed for analogue issues in disciplines other than medicine, how these can be transferred into medicine, and what the perspectives are for the traditional innovative field of head-and-neck-oncology.

Outcomes and complications of total hip replacement in super-obese patients

The purpose of this study was to examine the complications and outcomes of total hip replacement (THR) in super-obese patients (body mass index (BMI) > 50 kg/m2) compared with class I obese (BMI 30 to 34.9 kg/m2) and normal-weight patients (BMI 18.5 to 24.9 kg/m2), as defined by the World Health Organization.

A total of 39 THRs were performed in 30 super-obese patients with a mean age of 53 years (31 to 72), who were followed for a mean of 4.2 years (2.0 to 11.7). This group was matched with two cohorts of normal-weight and class I obese patients, each comprising 39 THRs in 39 patients. Statistical analysis was performed to determine differences among these groups with respect to complications and satisfaction based on the Western Ontario and McMaster Universities (WOMAC) osteoarthritis index, the Harris hip score (HHS) and the Short-Form (SF)-12 questionnaire.

Super-obese patients experienced significantly longer hospital stays and higher rates of major complications and readmissions than normal-weight and class I obese patients. Although super-obese patients demonstrated reduced pre-operative and post-operative satisfaction scores, there was no significant difference in improvement, or change in the score, with respect to HHS or the WOMAC osteoarthritis index.

Super-obese patients obtain similar satisfaction outcomes as class I obese and normal-weight patients with respect to improvement in their scores. However, they experience a significant increase in length of hospital stay and major complication and readmission rates.

Cite this article: Bone Joint J 2013;95-B:758–63.

Loss of retinal nerve fibre layer axons indicates white but not grey matter damage in early multiple sclerosis

BACKGROUND AND PURPOSE

Optical coherence tomography (OCT) has shown thinning of the retinal nerve fibre layer (RNFL) and total macular volume (TMV) in multiple sclerosis (MS) patients. Measures of retinal atrophy are associated with the brain parenchymal fraction (BPF) assessed by magnetic resonance imaging (MRI). However, in MS, data on the relation of OCT measures and grey and white matter volumes are contradictory. We performed a prospective cross-sectional study with a statistically pre-defined endpoint to test our hypothesis that OCT measures of neuro-axonal degeneration are related to global and partial brain atrophy in early forms of MS.

METHODS AND RESULTS

Forty-four patients with clinically isolated syndrome (n = 10) or relapsing-remitting MS (n = 34; mean disease duration = 3.2 years, median EDSS = 1.5) were enrolled in the study. Peripapillary- and volumetric OCT scans of the macula were performed using latest spectral-domain OCT technology. BPF as well as white and grey matter fractions (WMF/GMF) were assessed by 1.5 Tesla MRI scans. Generalized estimating equation models adjusted for age and linear regression statistics were used to assess the association between OCT and MRI measures. RNFL thickness, TMV and age were significantly associated with BPF. RNFL thickness and TMV independently predicted WMF (P = 0.003 and P = 0.032) but not GMF (P = 0.717 and P = 0.357) when corrected for age. In contrast, age was strongly associated with GMF (P < 0.001) but not WMF.

CONCLUSION

Our study suggests that, in early MS, OCT measures of retinal atrophy are related to volumetric changes in the white but not grey matter compartment as assessed by MRI. It further substantiates the association of retinal thinning and brain tissue loss in MS.

Loss of caveolin-1 from bronchial epithelial cells and monocytes in human subjects with asthma

BACKGROUND

Caveolin-1 has emerged as a critical regulator of signaling pathways involved in lung fibrosis and inflammation.

METHODS

Therefore, we investigated whether caveolin-1 is deficient in asthmatic patients and in a murine model of asthma.

RESULTS

Immunohistochemical analyses of endobronchial biopsies showed a remarkable loss of caveolin-1 in the lungs of asthmatic patients compared with controls. This loss was most evident in bronchial epithelial cells and associated with an increase in the expression of extracellular matrix proteins: collagen I, tenascin, and periostin. Cultured primary bronchial epithelial cells of asthmatics had lower caveolin-1 expression compared with control cells. In addition, caveolin-1 expression was significantly decreased in peripheral blood monocytes from asthma patients. The loss of caveolin-1 was also observed in a mouse model for asthma (mice sensitized and challenged with aspergillus fumigatus).

CONCLUSIONS

To our knowledge, this is the first demonstration that the regulatory protein caveolin-1 is reduced in patients with asthma.

Cause of death and correlation with autopsy findings in burns patients

OBJECTIVE

Global mortality from burns is decreasing however there is a relative paucity of mortality data in the literature from burns units in the United Kingdom. We present an analysis of burns deaths and correlation with coroners' autopsy findings from a large regional burns unit.

DESIGN

Retrospective medical note review of patients who died over a 7 year period (January 2005 to April 2011) was undertaken. Patient demographics were recorded in addition to: burn size, depth, length of stay, presence of inhalational injury, organs failing and diagnosis of sepsis. In order to evaluate the accuracy of our pre-mortem clinical diagnosis, we compared post-mortem cause of death with clinical cause of death.

RESULTS

There were 92 deaths out of 4745 admissions for acute burn (crude mortality 1.9%). 37 patients were immediately given comfort care and excluded from analysis. Average age was 52.9 years±19.4, average percentage burn 43.7%±26.8, and length of stay 26.4±45 days. 80% of deaths were attributable to flame burn (44/55), and 51% (28/55) suffered inhalational injury. Multi-organ failure was the primary cause of death (39/55), with sepsis being the primary trigger (20/39, 51%). Pseudomonas was the most common organism isolated in septic patients. There were significant difficulties in obtaining post-mortem reports and an obvious lack of correlation between coroners' reports and clinical cause of death.

CONCLUSIONS

The principal cause of mortality in our unit was multi-organ failure due to sepsis, which concurs with current literature. Autopsy has previously been shown to be a useful retrospective diagnostic tool, however we challenge its reliability as a result of our study.