OP0042 BLOCKING OF CD103+ TISSUE RESIDENT MEMORY T CELLS (TRM) AS A THERAPEUTIC STRATEGY IN SJOGREN’S SYNDROME

Background:

Tissue-resident memory T cells (TRM), are a recently identified T cells population featuring tissue localization and expression of markers of tissue homing, CD69 and CD103. Recently, the expansion of CD8+ TRMs and their involvement in the sialadenitis was described in a murine model of SS. However, CD4+ and CD8+ TRM’s functional relevance in pSS is still not fully understood, and the TRM therapeutic targeting unexplored.

Objectives:

The study aimed to address the role of CD4+ and CD8+ TRMs in the pathogenesis of pSS and to explore the therapeutic targeting of the tissue residency marker of TRM CD103.

Methods:

An animal model of experimental (ESS) obtained by immunization of female C57BL/6 mice (n=10) with salivary glands (SG) protein extract and Freund’s complete adjuvant used to investigate the dynamic of infiltration of SG by CD4+ and CD8+ TRMs, their frequency, and the impact of CD103 blockade. For the therapeutic intervention, at 10-weeks post-immunization, the salivary gland was cannulated via Wharton’s duct, and an anti-CD103 neutralizing antibody or vehicle-injected. The mice’s saliva flow rate was assessed, and SGs were analyzed by Flow-cytometry and immunohistochemistry (IHC).

The frequency and localization of TRMs was analyzed in minor SG of sicca syndrome (nSS) and pSS patients (n=39) by flow cytometry and IHC. The expression of genes involved in the tissue retention of TRMs was assessed in SG by RT-PCR.

Results:

Upon the ESS progression, a significant progressive increase in CD45+CD103+ cells frequency was observed from 5wk to 20wk post-immunization (p<0.001), where the CD8+ were the most abundant, followed by CD4+. Consistently, CD103+CD8+ T cells were detected within the lymphocytic infiltration of SG from ESS mice. Sorted purified SG CD10+CD3+CD8+ T cells showed higher Granzyme B, TNF-alpha expression compared to CD103-CD3+CD8+ at both mRNA and protein levels. Notably, ESS mice treated with anti-CD103 showed improvement in salivary function (p<0.05) and reduced lymphocytic infiltrations measured as focus score (FS) (p<0.01) and area-fraction (p<0.01). Consistently, anti-CD103 treatment consistently reduced CD103+ cells and IFN-gamma+, Granzyme B+, and TNFa+ CD8+ cells. We next performed phenotypic analysis of CD45+CD103+ immune cells in the SG of pSS patients observing an increase in both with CD8+CD103+CD69+ and CD4+CD103+CD69+ (p<0.05). Finally, IHC showed that the expansion of TRMs in pSS salivary glands was accompanied by a down-regulation of E-cadherin glandular expression and their migration outside the epithelium in the context of inflammatory infiltrates. SG of patients with pSS showed a significant up-regulation of BLIMP1, KFL-2, and S1PR1 and down-regulation of ITGB2. CXCL9 and CXCL10, and IL-15 involved in the tissue recruitment and long-term survival of TRMs were significantly modulated in pSS salivary glands.

Conclusion:

TRM are expanded and activated in the SG of pSS and ESS, participating in the organization of tissue inflammation. Although the mechanisms behind this expansion are still not fully understood, CD103 could be a valuable novel therapeutic target to prevent lymphocytic infiltrations and glandular destruction in Sjogren syndrome.

Disclosure of Interests:

None declared

POS0833 A RETROSPECTIVE COHORT STUDY IN CHINESE PATIENTS WITH ADULT POLYMYOSITIS AND DERMATOMYOSITIS: RISK OF COMORBIDITIES AND SUBCLASSIFICATION USING MACHINE LEARNING

Background:

Idiopathic inflammatory myopathy (IIM), also known as myositis, refers to a group of heterogeneous disorders including polymyositis (PM), dermatomyositis (DM), inclusion body myositis and immune-mediated necrotising myopathy. Phenotype, pathogenesis, and prognosis vary due to multi-organ involvement and comorbidities. With the clinical application of MSAs, a new classification system for myositis was explored to reduce confusion between subgroups. But it is far from showing the full picture of myositis due to high heterogeneity. Therefore, it is necessary to systematically evaluate the relevant risk factors of myositis for ILD, other rheumatic diseases, and malignancy for better clinical vigilance. And further exploring the subclassification of myositis is critical.

Objectives:

To identify the risk factors in Chinese patients with adult polymyositis and dermatomyositis for their comorbidities and explore a subclassification system.

Methods:

Clinical records of 397 patients with idiopathic inflammatory myopathies were retrospectively reviewed. Logistic regression was used to identify potential risk factors for interstitial lung disease (ILD), other rheumatic diseases, and malignancy after bivariate analysis. Hierarchical clustering and decisional tree were utilized to identify subgroups and explore a subclassification system.

Results:

A total of 119 polymyositis and 191 dermatomyositis patients were included. Anti-PM/Scl, anti-Ro52, anti-aminoacyl-tRNA synthetase and anti-MDA5 (adjusted odds ratios (AOR)=4.779, 1.917, 5.092 and 7.714 respectively) antibodies were risks (p<0.05), whereas overlapping malignancy was protective (AOR=0.107; p=0.002) for ILD across polymyositis, dermatomyositis and the total group. In subgroup models, Raynaud’s phenomenon, arthralgia and semi-quantitative anti-nuclear antibody (AOR=51.233, 4.261, 3.047 respectively) were risks for other overlapping rheumatic diseases (p<0.05). For overlapping malignancy, male and anti-TIF1γ antibodies (AOR=2.533, 16.949) were risks (p<0.05), whereas disease duration and combination of ILD (AOR=0.954, 0.106) were protective in the total group (p<0.05); while anti-NXP2 antibodies were identified as risk factors (AOR=73.152; p=0.038) in polymyositis. Hierarchical clustering suggested a subclassification with 6 subgroups: malignancy overlapping dermatomyositis, classical dermatomyositis, polymyositis with severe muscle involvement, dermatomyositis with ILD, polymyositis with ILD, and overlapping of myositis with other rheumatic diseases according to the characteristics of grouped patients. Accuracy of the classification and regression trees model was 0.768 (95% CI 0.711 to 0.819) on training set and 0.633 (95%CI 0.499 to 0.754) on test set.

Conclusion:

Accompanying ILD, other rheumatic diseases and malignancy are strongly associated with clinical manifestation and myositis-specific or myositis-associated autoantibodies among Chinese polymyositis and dermatomyositis patients. The subclassification system proposed a more precise phenotype defining toward stratified treatments.

Acknowledgements:

The study was supported by the Natural Science Foundation of China [No. 81803932] and the Natural Science Foundation of Guangdong Province [No. 2018030310025 and 2017A030313868]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Disclosure of Interests:

None declared

A functional variant in the promoter region of IGF1 gene is associated with chicken abdominal fat deposition

Insulin-like growth factor 1 (IGF1) plays an important role in the regulation of cell growth, proliferation, differentiation, and apoptosis. Previously several studies revealed that genotypes of chicken IGF1 c.-366A > C were significantly associated with abdominal fat weight and body weight in chickens. But the underlying mechanism is still unknown. To investigate the mechanism underlying the association, herein, we performed IGF1 gene mRNA expression profiling, a dual-luciferase reporter assay and electrophoretic mobility shift assay (EMSA). Quantitative real-time PCR results showed that IGF1 gene was widely expressed in 14 tissues. The mRNA expression levels of IGF1 gene in both abdominal fat and jejunum were significantly higher in fat broilers than in lean broilers. However, the opposite results were observed in the pancreas. The reporter gene assay showed that the promoter luciferase activity of allele A was significantly higher than that of allele C (P < 0.05). In addition, the luciferase activity of allele A promoted by the transcription factor AP1 and OCT1 was higher than that of allele C (P < 0.05). Electrophoretic mobility shift assay result showed that allele A binding to the transcription factor AP1 and OCT1 was stronger than that of allele C. All in all, our data indicated that the IGF1 gene c.-366A > C is a functional SNP responsible for chicken adipose deposition.

MiR-802 inhibits the malignant biological behavior of oral squamous cell carcinoma by targeting proto-oncogene MET

OBJECTIVE

Oral squamous cell carcinoma (OSCC) is one of the frequently occurring malignancies, but effective treatments are lacking. It is believed that exploring new molecular targets could help us to improve the treatment of OSCC. Therefore, we hope to find a new miRNA target to control OSCC.

PATIENTS AND METHODS

qPCR and Western blots were used to test the expressions of miR-802 and target gene in OSCC tissues and cell lines. Luciferase reporter assay was performed to check whether miR-802 could directly target MET. CCK-8, wound healing, cell invasion, colony formation, and tumor growth assays were used to determine the functions of miR-802 and MET in the malignant biological behavior of OSCC.

RESULTS

The results suggested that miR-802 was low expressed in OSCC tissues and cell lines. Overexpression of miR-802 inhibited the cell viability, colony formation, migration and invasion of Tca8113 and SCC9 cells, and tumor growth in vivo. It was predicted that miR-802 might target the mRNA of proto-oncogene MET. Overexpressing miR-802 suppressed the expression of wild-type MET at both protein and mRNA levels in Tca8113 and SCC9 cells. Moreover, the expression of MET was high and significantly correlated with the low expression of miR-802 in OSCC tissues. Overexpression of MET in Tca8113 and SCC9 cells reduced the tumor-suppressive effects, which was induced by miR-802 overexpression.

CONCLUSIONS

MiR-802 suppresses the malignant biological behavior of OSCC by targeting proto-oncogene MET. This work provides a new potential molecular target for treating OSCC.

Clinical outcomes of COVID-19 in long-term care facilities for people with epilepsy

In this cohort study, we aim to compare outcomes from coronavirus disease 2019 (COVID-19) in people with severe epilepsy and other co-morbidities living in long-term care facilities which all implemented early preventative measures, but different levels of surveillance. During 25-week observation period (16 March-6 September 2020), we included 404 residents (118 children), and 1643 caregivers. We compare strategies for infection prevention, control, and containment, and related outcomes, across four UK long-term care facilities. Strategies included early on-site enhancement of preventative and infection control measures, early identification and isolation of symptomatic cases, contact tracing, mass surveillance of asymptomatic cases and contacts. We measured infection rate among vulnerable people living in the facilities and their caregivers, with asymptomatic and symptomatic cases, including fatality rate. We report 38 individuals (17 residents) who tested severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive, with outbreaks amongst residents in two facilities. At Chalfont Centre for Epilepsy (CCE), 10/98 residents tested positive: two symptomatic (one died), eight asymptomatic on weekly enhanced surveillance; 2/275 caregivers tested positive: one symptomatic, one asymptomatic. At St Elizabeth's (STE), 7/146 residents tested positive: four symptomatic (one died), one positive during hospital admission for symptoms unrelated to COVID-19, two asymptomatic on one-off testing of all 146 residents; 106/601 symptomatic caregivers were tested, 13 positive. In addition, during two cycles of systematically testing all asymptomatic carers, four tested positive. At The Meath (TM), 8/80 residents were symptomatic but none tested; 26/250 caregivers were tested, two positive. At Young Epilepsy (YE), 8/80 children were tested, all negative; 22/517 caregivers were tested, one positive. Infection outbreaks in long-term care facilities for vulnerable people with epilepsy can be quickly contained, but only if asymptomatic individuals are identified through enhanced surveillance at resident and caregiver level. We observed a low rate of morbidity and mortality, which confirmed that preventative measures with isolation of suspected and confirmed COVID-19 residents can reduce resident-to-resident and resident-to-caregiver transmission. Children and young adults appear to have lower infection rates. Even in people with epilepsy and multiple co-morbidities, we observed a high percentage of asymptomatic people suggesting that epilepsy-related factors (anti-seizure medications and seizures) do not necessarily lead to poor outcomes.

[Perioperative safety and feasibility of simultaneous off-pump coronary artery bypass grafting with non-cardiac surgical procedures of moderate-to-severe severity]

Objective: To examine the perioperative safety and feasibility of simultaneous off-pump coronary artery bypass grafting (OPCAB) with non-cardiac surgical procedures of moderate-to-severe severity. Methods: The perioperative results of 54 patients underwent simultaneous OPCAB with non-cardiac surgical procedures from September 2013 to January 2019 at Department of Cardiac Surgery, Peking University First Hospital were assessed retrospectively. There were 46 males and 8 females, aging (65.8±8.8) years (range: 41 to 85 years). All simultaneous non-cardiac surgical procedures, including vascular (n=1), thoracic (n=26), general (n=12) and urologic surgical procedures (n=15), were assessed to be of moderate-to-severe grade by operative severity scoring system. Perioperative results were compared between the OPCAB patients who underwent simultaneous non-cardiac surgical procedures (n=54) and 1∶2 matched patients who underwent isolated OPCAB performed most recently by the same cardiac team with similar procedures accordingly (n=108), using t test, Mann-Whitney U test, χ² test or Fisher exact test. Results: All baseline factors were matched between the two groups, with no significant difference on European system for cardiac operative risk evaluation (EuroSCORE) Ⅱ (1.185(0.758)% vs. 1.215(0.905)%, Z=‒0.036, P=0.972). No perioperative death was observed in the two groups. Although patients underwent simultaneous non-cardiac surgical procedures showed prolonged operation duration time ((324.9±97.1) minutes vs. (166.7±36.7) minites, t=11.564, P<0.01) and increased intraoperaive blood loss ((462.2±269.6) ml vs. (304.5±177.8) ml, t=3.866, P<0.01), primary postoperative complications, including perioperative myocardial infarction, atrial fibrillation, perioperative stroke, acute renal failure, wound infection, and bleeding reoperation did not show significant differences between the two groups (all P>0.05), while total blood transfusion volume, mechanical ventilation time and intensive care unit residence time also showed no significant differences between the two groups (all P>0.05). Conclusion: Simultaneous OPCAB with non-cardiac surgical procedures of moderate-to-severe severity in patients with operative indications are safe and feasible, and are not associated with increased postoperative risks when compared with isolated OPCAB.

Dose-response relationship between serum fibroblast growth factor 21 and liver fat content in non-alcoholic fatty liver disease

BACKGROUND & AIM

Although serum fibroblast growth factor 21 (FGF21) levels are associated with liver fat content in non-alcoholic liver fat disease (NAFLD), the precise nature of the association remains undetermined. Therefore, this study aimed to explore the potential dose-response relationship between FGF21 and liver fat content in NAFLD.

METHODS

For this exploratory study from a randomized trial, 220 NAFLD patients with central obesity were recruited via community-based screening and randomly assigned to either control, moderate or vigorous-moderate exercise groups for 12 months. After this exercise intervention, patients were followed-up for a further 12 months. Serum FGF21 levels were measured by ELISA. Intrahepatic triglyceride (IHTG) content was determined by proton magnetic resonance spectroscopy.

RESULTS

Of the 220 patients, 149 (67.7%) were female; mean age was 53.9 ± 7.1 years and mean BMI was 28.0 ± 2.9 kg/m² for all patients. Baseline IHGT increased gradually (P = 0.029 for trend) according to baseline serum FGF21 quartiles 1, 2, 3 and 4 (212.3, 358.9, 538.7 and 793.5 pg/mL, respectively). On grouping the distribution of serum FGF21 level changes into quartiles at month 12, the relative IHTG loss increased as serum FGF21 levels were reduced (P = 0.004 for trend). A similar trend was observed at month 24 (P = 0.006 for trend). Multivariate linear regression analysis revealed that changes in serum FGF21 levels were independently associated with changes in IHTG at both month 12 [β (SE), 0.136 (0.118); P = 0.048] and month 24 [β (SE), 0.152 (0.139); P = 0.041]. Using restricted cubic spline regression, changes in serum FGF21 were strongly and positively associated with their corresponding relative IHTG loss at both month 12 and follow-up (P_overall = 0.017, P_non-linear = 0.044 and P_overall = 0.020, P_non-linear = 0.361, respectively, for dose-response).

CONCLUSION

Serum FGF21 is strongly associated with liver fat content in a dose-response manner in centrally obese NAFLD patients. These findings support the use of serum FGF21 as a biomarker of liver fat content in NAFLD.

[Effect of c-myc gene silence on the expression of oncogenes and apoptotic genes in hepatocytes treated with PM(2).5]

Objective: To construct the c-myc gene silenced hepatocytes, study the effect of c-myc gene silence on expression of oncogenes and apoptosis genes in hepatocytes treated with PM2.5. Methods: According to the c-myc gene mRNA sequence provided by GenBank, three interfering sequences were designed and synthesized, the recombinant lentiviral vector was transfected into L02 hepatocytes. The real-time quantitative PCR and western blotting were used to identify the effect of c-myc gene silencing. L02 cells and c-myc gene silenced cells were used as experimental subjects. The normal L02 cells and c-myc silenced cells were treated with 50 μg/ml PM(2.5) water soluble solution, 10 μM positive control Cr(6+) and a blank control, the treatment period was 24 h. The mRNA levels of oncogenes (c-myc, c-fos, k-ras, p53) and apoptotic genes (Caspase-3, Caspase-8, Caspase-9) were detected by real-time PCR. The protein levels of oncogenes and apoptotic genes were detected by western blotting. Results: The mRNA level and protein level of c-myc decreased by 81% and 70% in c-myc silenced cells when compared with the normal L02 hepatocytes, the above results indicate that c-myc gene silenced cells were successfully constructed. After c-myc silenced cells were treated with PM2.5 water soluble solution, The mRNA levels of c-myc, c-fos, and k-ras decreased by 84.1%, 45.4%, and 54.6% (P<0.05) , p53 increased by 192.9% (P<0.05) , and the expression of Caspase-3, Caspase-8, and Caspase-9 decreased by 24.4%, 36.1%, 60.9% (P<0.05) . In the Cr(6+) positive control group, the expression of c-myc, c-fos, and k-ras decreased by 72.1%, 82.2%, and 54.0% (P<0.05) , p53 increased by 250.0% (P<0.05) , the expression of Caspase-3, Caspase-8, and Caspase-9 decreased by 34.6%, 36.0%, 68.9% (P<0.05) , respectively, when compared with the normal L02 hepatocytes (P<0.05) . Western blotting results showed that the protein levels of c-myc and c-fos increased, p53 decreased after PM(2.5) exposure; the protein levels of Caspase-3, Caspase-8, Caspase-9 increased after PM(2.5) exposure (P<0.05) . When in comparison with the c-myc silenced group, the protein levels of c-myc and c-fos decreased, p53 protein increased in PM(2).5 exposed group (P<0.05) . Conclusion: c-myc gene silenced cells were successfully constructed in this paper. PM(2.5) could promote the expression of oncogenes and apoptotic genes in L02 cells, and c-myc gene silencing can inhibit the expression of oncogenes and apoptotic genes after PM(2.5) treatment in L02 cells.

Research Note: Responses of growth performance, immune traits, and small intestinal morphology to dietary supplementation of chromium propionate in heat-stressed broilers

This study was conducted to investigate the dose responses of growth performance, immune traits, and small intestinal morphology to dietary supplementation of chromium propionate (CrPro) in heat-stressed broilers. A total of 252 1-day-old Cobb 500 male broilers were randomly assigned to 6 treatments with 7 replicate cages of 6 birds per cage. The dietary treatments consisted of a basal diet supplemented with 0, 0.2, 0.4, 0.8, 1.6, and 3.2 mg/kg Cr in the form of CrPro. The birds had ad libitum access to feed and tap water for an experimental period of 42 D. For induction of heat stress, the house temperature was set at 35°C ± 2°C from 22 to 42 D of age. No differences were detected among treatments in growth performance during the experimental period (P > 0.05). Serum IgA concentrations were not affected by treatment (P > 0.05). However, a quadratic response was detected for serum IgG (P < 0.01) and IgM (P < 0.01) concentration as dietary Cr supplementation was increased. The highest response of IgG and IgM in serum was observed for broilers fed a diet supplemented with 0.2 mg of Cr/kg. Dietary supplementation of Cr had no impacts on villus height, crypt depth, or the ratio of villus height to crypt depth in the jejunum and ileum. A quadratic response of villus height and the ratio of villus height to crypt depth and a linear response of crypt depth to increased dietary Cr supplementation were observed in the duodenum (P < 0.01). The results indicate that CrPro supplementation could modify the intestinal morphology of the duodenum and influence serum IgG and IgM concentrations in heat-stressed broiler chickens. Based on the results of this experiment, the 0.2-mg Cr/kg diet from CrPro increases immune response and intestinal health in heat-stressed broilers.

[Expression, purification and polyclonal antibody preparation of the Schistosoma japonicum SjGrpE protein]

OBJECTIVE

To investigate the biological properties of Schistosoma japonicum SjGrpE protein, and to express and purify the recombinant SjGrpE protein and test its immunogenicity.

METHODS

The amino acid composition, molecular weight, hydrophilicity and hydrophobicity, transmembrane region, signal peptide, localization, phosphorylation site, ubiquitination site, glycosylation site, secondary and tertiary structures and B cell epitopes of the SjGrpE protein were predicted using bioinformatics analyses. The SjGrpE gene was amplified using PCR assay using S. japonicum cDNA as a template, double enzyme-digested and linked to the pET28a vector to yield the recombinant plasmid pET28a-SjGrpE. The recombinant plasmid pET28a-SjGrpE was transformed into Escherichia coli BL21, and then IPTG was employed to induce the expression of the target protein, which was purified by nickel ion affinity chromatography. After mice were immunized with the recombinant SjGrpE protein, mouse sera were collected, and the polyclonal antibody against the SjGrpE protein was characterized.

RESULTS

SjGrpE protein, which was identified as a hydrophilic protein, was predicted to have a molecular weight of approximately 24.3 kDa without transmembrane regions or signal peptides, and locate in the mitochondrion. SjGrpE protein contained 18 phosphorylation sites and 2 ubiquitination sites, but had no glycosylation sites. In addition, SjGrpE protein contained 5 B-cell epitopes. The full length of SjGrpE gene was approximately 660 bp. The recombinant pET28a-SjGrpE plasmid was successfully generated, and the recombinant SjGrpE protein was obtained following the affinity chromatography, which stimulated mice to secrete high-titer antibodies.

CONCLUSIONS

The recombinant SjGrpE protein has been successfully prepared and this recombinant protein has a high immunogenicity, which provides a basis for evaluating its value as a vaccine candidate for S. japonicum infections.

Impaired naming performance in temporal lobe epilepsy: language fMRI responses are modulated by disease characteristics

OBJECTIVE

To investigate alterations of language networks and their relation to impaired naming performance in temporal lobe epilepsy (TLE) using functional MRI.

METHODS

Seventy-two adult TLE patients (41 left) and 36 controls were studied with overt auditory and picture naming fMRI tasks to assess temporal lobe language areas, and a covert verbal fluency task to probe frontal lobe language regions. Correlation of fMRI activation with clinical naming scores, and alteration of language network patterns in relation to epilepsy duration, age at onset and seizure frequency, were investigated with whole-brain multiple regression analyses.

RESULTS

Auditory and picture naming fMRI activated the left posterior temporal lobe, and stronger activation correlated with better clinical naming scores. Verbal fluency MRI mainly activated frontal lobe regions. In left and right TLE, a later age of epilepsy onset related to stronger temporal lobe activations, while earlier age of onset was associated with impaired deactivation of extratemporal regions. In left TLE patients, longer disease duration and higher seizure frequency were associated with reduced deactivation. Frontal lobe language networks were unaffected by disease characteristics.

CONCLUSIONS

While frontal lobe language regions appear spared, temporal lobe language areas are susceptible to dysfunction and reorganisation, particularly in left TLE. Early onset and long duration of epilepsy, and high seizure frequency, were associated with compromised activation and deactivation patterns of task-associated regions, which might account for impaired naming performance in individuals with TLE.

Motor hyperactivation during cognitive tasks: An endophenotype of juvenile myoclonic epilepsy

OBJECTIVE

Juvenile myoclonic epilepsy (JME) is the most common genetic generalized epilepsy syndrome. Myoclonus may relate to motor system hyperexcitability and can be provoked by cognitive activities. To aid genetic mapping in complex neuropsychiatric disorders, recent research has utilized imaging intermediate phenotypes (endophenotypes). Here, we aimed to (a) characterize activation profiles of the motor system during different cognitive tasks in patients with JME and their unaffected siblings, and (b) validate those as endophenotypes of JME.

METHODS

This prospective cross-sectional investigation included 32 patients with JME, 12 unaffected siblings, and 26 controls, comparable for age, sex, handedness, language laterality, neuropsychological performance, and anxiety and depression scores. We investigated patterns of motor system activation during episodic memory encoding and verb generation functional magnetic resonance imaging (fMRI) tasks.

RESULTS

During both tasks, patients and unaffected siblings showed increased activation of motor system areas compared to controls. Effects were more prominent during memory encoding, which entailed hand motion via joystick responses. Subgroup analyses identified stronger activation of the motor cortex in JME patients with ongoing seizures compared to seizure-free patients. Receiver-operating characteristic curves, based on measures of motor activation, accurately discriminated both patients with JME and their siblings from healthy controls (area under the curve: 0.75 and 0.77, for JME and a combined patient-sibling group against controls, respectively; P < .005).

SIGNIFICANCE

Motor system hyperactivation represents a cognitive, domain-independent endophenotype of JME. We propose measures of motor system activation as quantitative traits for future genetic imaging studies in this syndrome.

THU0270 ONLINE INTERACTION AND FREQUENT SELF-ASSESSMENTS PROMOTED TREAT-TO-TARGET FOR SLE VIA EMPOWERING PATIENTS: A COHORT STUDY FROM CHINA BY SMART SYSTEM OF DISEASE MANAGEMENT (SSDM)

Background:

Treating to target (T2T) is routine in RA, but no comparable standard has been defined for SLE. In 2015, the definition of Lupus Low Disease Activity State (LLDAS) was generated by Asia-Pacific Lupus Collaboration, and the preliminary validation demonstrated its attainment to be associated with improved outcomes in SLE. A SLEDAI-2K score lower than 4 is the main criteria for LLDAS. SSDM is an interactive mobile disease management application, including application systems for both the doctors and patients.

Objectives:

To evaluate the patterns of T2T and related influential factors among SLE patients after applying SSDM in real world.

Methods:

Patients were trained to master SSDM by healthcare professionals in clinics. The first assessment for SLEDAI-2K was performed as the baseline. Patients were required to perform repeated self-assessments after leaving the clinics. The data is synchronized to the SSDM of authorized rheumatologists. Based on the patients’ data, rheumatologists will provide medical advices to the patients.

Results:

From July 2015 to Jan 2020, 32,559 SLE patients enrolled in SSDM. The mean age is 36.35 years old and median disease duration is 3.85 years. Among them 1,937 SLE patients from 134 hospitals across China were followed up for more than 12 months, and the demographics were summarized in table 1.

Table 1.Baseline\Final follow-upn%x <= 4%5 <= x <= 9%10 <= x <= 14%15 <= x%x <= 4104053.69%82078.85%13512.98%504.81%353.37%5 <= x <= 935718.43%23064.43%6016.81%328.96%359.80%10 <= x <= 1422211.46%12054.05%3817.12%4018.02%2410.81%15 <= x31816.42%15649.06%4915.41%4714.78%6620.75%Total1937100%132668.46%28214.56%1698.72%1608.26%

The ratio of T2T achievers was 53.69% (1,040/1,937) at the baseline and improved significantly to 68.46% (1,326/1,937) after a 12-month follow-up, p<0.01. Among T2T achievers at the baseline, 78.85% (820/1,040) maintained T2T, and 21.15% (220/1,040) relapsed. Of patients who didn’t achieve T2T at baseline, 56.41% (506/897) of the patients achieve T2T after 12-month follow-up.

The impact of the online interaction and the frequency of self-assessment for SLEDAI-2K on T2T has been analyzed. Compared with 1,475 patients who didn’t interact online with their physicians through SSDM, 462 patients with online interaction achieved higher rate of T2T improvement (19.48% vs 13.29%, p<0.05). The more frequent of the self-assessments being performed by patients, the higher improvement of T2T rate will be. The improvement rates of T2T in the subgroups which self-assessed with SSDM by quarterly, bimonthly and monthly were 8.56%, 16.14% and 23.24% respectively. The improvement rate (y) of T2T was positively correlated with the frequency of self-assessment for SLEDAI-2K(x) independently, r = 0.9998. (Figure 1)

Conclusion:

After proactive disease management via SSDM for more than 12 months, the rate of T2T in SLE patients increased significantly. Online interaction between patients and physicians contributed in promoting T2T improvement rate. The patients who performed more self-assessments through SSDM had higher probability of T2T achievement. SSDM is a valuable tool for long term SLE follow-up through empowering patients.

References:

Acknowledgments:

SSDM was developed by Shanghai Gothic Internet Technology Co., Ltd.

Disclosure of Interests:

None declared

SAT0250 CLINICAL CHARACTERISTICS AND THE DISEASE ACTIVITY OF BEHCET’S DISEASE IN CHINA: A STUDY BASED ON SMART SYSTEM OF DISEASE MANAGEMENT (SSDM)

Background:

Behcet´s disease (BD) is a systemic autoimmune disease that affects multiple organ systems with recurrent oral ulcers, genital ulcers and skin lesions. Behcet´s Disease Current Activity Form (BDCAF) and Electronic Medical Record-based Activity Index (EMRAI) are commonly used internationally to evaluate the disease activity of BD.

Objectives:

This study aimed to analyze the clinical characteristics, the level of disease activity, and the incidence of anxiety and depression for Chinese BD patients. Patients can perform self-management of disease with SSDM.

Methods:

SSDM is a series of doctor-patient interactive applications for self-management of patients with chronic diseases. Patients can perform self-assessment with SSDM and upload the data to their authorized doctors. The SSDM patients’ application system integrates the BDCAF and EMRAI into one scoring system. Patients could obtain scores of BDCAF and EMRAI by responding to one questionnaire through SSDM.

Results:

From Apr 2017 to Jan 2020, 719 BD patients from 166 hospitals used SSDM, with a mean age of 38.97±12.71 (14~81) years old, and median disease duration of 20.8 months. 719 patients performed BDCAF and EMRAI self-assessment 1321 times, 252 patients repeat assessments for 855 times. The mean score of BDCAF and EMRAI are 3.57±2.17 and 3.44±1.90, respectively. The matching degree of the two score was 0.8747.

The most common clinical characteristics were oral ulcers (83.73%), ocular symptoms (62.03%), joint pain (50.07%). The comparative study between males and females revealed significant difference in the aspects of epididymitis (10.94% vs 0, p<0.001), genital ulcer (35.09% vs 44.93%, p=0.01), headache (24.15% vs 33.92%, p=0.01) and superficial thrombophlebitis (24.15% vs 33.92%, p=0.01). Table 1.

Table 1.

Clinical Characteristics of different systems in Chinese BD patients.

Presence of clinical characteristicsTotalMalesFemalesP valueOral ulcer83.73% (602)86.42% (229)82.16% (373)0.14Genital ulcer41.31% (297)35.09% (93)44.93% (204)0.01*Epididymitis4.03% (29)10.94% (29)0 (0)<0.001**Erythema29.49% (212)29.43% (78)29.52% (134)0.98Skin lesions26.84% (193)28.68% (76)25.77% (117)0.4Superficial thrombophlebitis30.32% (218)24.15% (64)33.92% (154)0.01*Headache30.32% (218)24.15% (64)33.92% (154)0.01*Joint pain50.07% (360)51.32% (136)49.34% (224)0.61Arthritis14.60% (105)14.72% (39)14.54% (66)0.95Gastrointestinal involvement24.90% (179)27.92% (74)23.13% (105)0.15Ocular symptoms62.03% (446)62.64% (166)61.67% (180)0.79Nervous involvement23.78% (171)25.66% (68)22.69% (103)0.37Vascular involvement15.72% (113)18.11% (48)14.32% (65)0.18

*P values are for the comparison between the males and females.

Conclusion:

Chinese BD patients can effectively perform BDCAF and EMRAI self-assessment with SSDM. The results of the assessment conducted by the two scoring systems are similar. The clinical characteristics of Chinese BD were different depending on gender.

Acknowledgments: :

Smart system of disease management (SSDM) was developed by Shanghai Gothic Internet Technology Co., Ltd.

Disclosure of Interests:

None declared

FRI0593 CORRELATION BETWEEN DISEASE ACTIVITY AND MENTAL HEALTH OF AS PATIENTS: A CROSS-SECTION STUDY WITH SELF-ASSESSMENTS BASED ON SMART SYSTEM OF DISEASE MANAGEMENT (SSDM) MOBILE TOOLS

Background:

WHO survey showed that the prevalence of anxiety and depression in Chinese population and Chinese patients with chronic diseases were between 3.1% - 4.2% and 3.1% - 7.3%, respectively. Ankylosing Spondylitis Disease Activity Score (ASDAS) and Hospital Anxiety and Depression Scale (HADS) are commonly used to evaluate AS patients’ disease activity and mental health. All those assessments were mainly performed by health professionals (HCPs) with paper questionnaire previously. SSDM is a novel smart disease management tool that allows patients to do self-assessments on ASDAS and HADS by mobile terminals.

Objectives:

To estimate the prevalence of anxiety and depression in Chinese patients with AS and to analyze the potential association between disease activity and mental health.

Methods:

Under the guidance and training by HCPs, AS patients downloaded SSDM and performed self-assessments bundle of ASDAS and HADS with SSDM. ASDAS<=1.3, 1.3-2.1, 2.1-3.5 and >3.5 are defined as inactive (IDA), moderate (MDA), high (HDA) and very high (VHDA) disease activity, respectively. ASDAS score <=1.3 represents inactive disease status and achievement of T2T. HADS score >=8 can be diagnosed with anxiety or depression.

Results:

From June 2016 to Jan 2020, 1,931 AS patients (1,118 male, 813 female) with a mean age of 34.09 ± 11.86 (12-82) years and the median disease duration of 2.61 years from 207 hospitals performed bundle self-assessments for 2,477 times in total. According to the HADS and ASDAS assessment results, the prevalence of anxiety and depression in all patients was 36.7% and 39.3% respectively, which was significantly higher than that in the WHO survey in Chinese population and chronic disease patients. The proportion of patients achieved and failed on T2T was 29% and 71%, respectively. The prevalence of anxiety (A) and depression (D) was 25% and 23% among T2T achievers; and 37% and 32% among T2T failures, respectively (pA<0.05, pD<0.05).

According to ASDAS, in IDA, MDA, HDA and VHDA subgroups, the prevalence of anxiety and depression was 27%, 36%, 41%, 52% and 29%, 38%, 45%, 56%, respectively. The correlation coefficients of anxiety (A) and depression (D) with ASDAS were rA=0.9908 and rD=0.9964. It suggested that with the increase of disease activity, the proportion of AS patients with anxiety and depression increased significantly. (Figure 1)

Figure 1.

The prevalence of anxiety and depression according to ASDAS.

Conclusion:

The prevalence of anxiety and depression in AS patients was significantly higher than that in the WHO survey in Chinese population and chronic disease patients. Higher prevalence of anxiety and depression were associated with higher levels of disease activity. SSDM is an effective mobile interface to monitor and study entanglement of disease activity and mental health in AS patients, which build a foundation for proactive interventions in future.

Acknowledgments:

Smart system of disease management (SSDM) was developed by Shanghai Gothic Internet Technology Co., Ltd.

Disclosure of Interests:

None declared

THU0252 CORRELATION BETWEEN DISEASE ACTIVITY AND MENTAL HEALTH IN SLE PATIENTS: A CROSS-SECTION STUDY WITH SELF-ASSESSMENTS BASED ON SMART SYSTEM OF DISEASE MANAGEMENT (SSDM) MOBILE TOOLS

Background:

WHO survey showed that the prevalence of anxiety and depression in Chinese population and Chinese patients with chronic diseases were between 3.1% - 4.2% and 3.1% - 7.3%, respectively. SLEDAI-2K and Hospital Anxiety and Depression Scale (HADS) are commonly used to evaluate SLE patients’ disease activity and mental health. All the Assessments were mainly performed by health professionals (HCPs) with paper questionnaire previously. SSDM is a novel smart disease management tool that allows patients to do self-assessments on SLEDAI-2K and HADS by mobile App.

Objectives:

To investigate the prevalence of anxiety and depression in Chinese patients with SLE and to analyze the potential association between disease activity of SLE and mental health.

Methods:

Under the guidance and training by HCPs, SLE patients downloaded SSDM and performed self-assessments bundle of SLEDAI-2K and HADS with SSDM. SLEDAI-2K <=4, 5-9, 10-14 and >=15 are defined SLE inactive, low (LDA), moderate (MDA) and high (HDA) disease activity, respectively. SLEDAI-2K score <= 4 is set as the main criteria for Lupus Low Disease Activity State (LLDAS) and achievement of T2T. HADS score >=8 can be diagnosed with anxiety or depression.

Results:

From June 2016 to Jan 2020, 3,332 SLE patients (199 male, 3,133 female) with a mean age of 36.34 ± 12.80 (10-91) years and the median disease duration of 3.43 years from 216 hospitals performed bundle self-assessments for 4,967 times in total. According to the HADS and SLEDAI-2K Assessment results, the prevalence of anxiety and depression in all patients was 36.7% and 39.3% respectively, which was significantly higher than that in the WHO survey in Chinese population and chronic disease patients. The proportion of patients achieved and failed on LLDAS was 53% and 47%, respectively. The prevalence of anxiety (A) and depression (D) was 19% and 27% among LLDAS achievers; 41% and 47% among LLDAS failures, respectively (pA<0.01, pD<0.01).

According to SLEDAI-2K, in LLDAS, LDA, MDA and HDA subgroups, the prevalence of anxiety and depression was 19%, 30%, 37%, 54% and 27%, 36%, 44%, 61%, respectively. The correlation coefficients of anxiety (A) and depression (D) with SLEDAI-2K were rA=0.9957 and rD=0.9819. It suggested that with the increase of disease activity, the proportion of SLE patients with anxiety and depression increased significantly. (Figure 1)

Conclusion:

Conclusion: Higher prevalence of anxiety and depression were Associated with higher levels of disease activity in SLE patients. SSDM is an effective mobile interface to monitor and study entanglement of disease activity and mental health in SLE patients, which build a foundation for proactive interventions physically and mentally in future.

References:

Acknowledgments:

SSDM was developed by Shanghai Gothic Internet Technology Co., Ltd.

Disclosure of Interests:

None declared

SAT0646-HPR PATTERN AND INFLUENTIAL FACTORS IN PROMOTING TREAT-TO-TARGET (T2T) FOR FOLLOW-UP OF ANKYLOSING SPONDYLITIS (AS) PATIENTS WITH A RHEUMATOLOGIST-PATIENT INTERACTIVE SMART SYSTEM OF DISEASE MANAGEMENT (SSDM): A COHORT STUDY FROM CHINA

Background:

Ankylosing Spondylitis Disease Activity Score (ASDAS) is adopted to evaluate the degree of disease activity and the inflammatory response in AS patients. ASDAS score <= 1.3 represents inactive disease status and achievement of T2T. SSDM is a mobile application for disease management.

Objectives:

To evaluate the patterns of T2T and related influential factors among AS patients after applying SSDM in the real world.

Methods:

AS Patients were trained to master SSDM by healthcare professionals (HCPs) and to conduct ASDAS self-assessments. Patients were also required for repeating self-assessments after leaving the hospital. After entry by patients, data can be synchronized to the SSDM terminal of authorized rheumatologists. Based on these data, the patients can apply for consultation to their physicians and rheumatologists can provide medical advices to their patients.

Results:

From Jan 2015 to Jan 2020, 17,870 AS patients enrolled in SSDM with the mean age of 34.62±10.98 years old and the median disease duration of 3.58 years. Among them, 1,127 AS patients from 150 hospitals were followed up for more than 6 months through SSDM. The results at baseline and in final follow up were summarized in Table 1.

Table 1.

The T2T results at baseline and in final follow up.

Baseline\Final follow-upn%x <= 1.3%1.3 < x <= 2.1%2.1 < x <= 3.5%3.5 < x%x <= 1.331527.95%20665.40%7423.49%268.25%92.86%1.3 < x <= 2.134030.17%13840.59%11433.53%7522.06%133.82%2.1 < x <= 3.536332.21%9526.17%10629.20%13336.64%297.99%3.5 < x1099.67%2422.02%2522.94%4238.53%1816.51%Total1,127100%46341.08%31928.31%27624.49%696.12%

The rate of T2T achievers were 27.95% (315/1,127) at baseline, and improved significantly to 41.08% (463/1,127) after 6 months follow up, p<0.01. Among T2T achievers at baseline, 65.40% (206/315) maintained T2T, 34.60% (109/315) relapsed. Of patients who didn’t achieve T2T at baseline, only 31.65% (257/812) achieved T2T after 6 months follow up.

The impact of the online interaction between patients and physicians and the frequency of self-assessment for ASDAS on T2T has been analyzed. Compared with 544 patients who didn’t interact online with their physicians and self-assessed less than 3times, 104 patients with online interaction and monthly assessments achieved significant higher improvement rate of T2T (9.19% vs 23.08%, p<0.01). The more frequent of the self-assessments being performed by patients, the higher improvement of T2T rate will be. The improvement of T2T rate(y) was positively correlated with times of self-assessment for ASDAS(x) independently. The regression equation as “y = 0.0304x + 0.0521”, r = 0.9107, p<0.01 (Figure 1).

Figure 1.

Conclusion:

Significant improvement was observed under applying SSDM through empowering AS patients. After proactive disease management via SSDM for more than 6 months, patients with ASDAS<=1.3 score at baseline had a significantly higher retention rate of inactive disease activity. The patients who performed more frequent self-assessments had lower probability of relapse and higher rate of T2T. Online interaction between patients and physicians contributed to promote the improvement rate of T2T. SSDM is a valuable tool for long term follow-up through empowering patients.

Acknowledgments:

SSDM was developed by Shanghai Gothic Internet Technology Co., Ltd.

Disclosure of Interests:

None declared

SAT0647-HPR DEVELOP A MACHINE LEARNING MODEL AND ALGORITHM BASED ON SMART SYSTEM OF DISEASE MANAGEMENT (SSDM) BIG DATA FOR RA FLARE PREDICTION

Background:

Flare, relapse from status of treat-to-target (T2T, DAS28<=3.2), is hard predicted. We try to make it predictable by applying machine learning to a database from smart system of disease management (SSDM). SSDM is an interactive mobile disease management APPs.

Objectives:

To develop and validate machine learning algorithms for flare prediction in RA.

Methods:

Patients were trained using SSDM and input their data, including demographic, comorbidities (COMBs), lab test, medications and monthly self-assessments, including DAS28, HAQ, SF-36, Hospital Anxiety and Depression Scale (HADS). The data was uploaded to cloud and synchronized to the mobile of authorized rheumatologists. The COMBs were by ICD-9, and medications were listed as cDMARDs, Bio (BioDMARDs), NSAIDs, Steroid, FS (food supplements), MC (medicine for COMBs), TCM (Traditional Chinese Medicine), and combinations.

Results:

From Jan of 2015 to Jan of 2020, 8811 RA patients, 85% female and 15% male, used to reach T2T. 4556 were flare-free and 4255 suffering at least one flare. The average 160 attributes were extracted from each flare-free patient at time of reaching T2T, and each flare patients at time of 3 months before the flare. Patients were randomly assigned as model setup (training) group (70%) and validation (testing) group30%.

For training, data were processed using Python with statistical analyses in R. In R, random forests were implemented. Logistic regression via glm in base R. The random forest comprises a set of decision trees. “Splits” in the decision trees reflect binary (i.e., yes/no) respect to attributors. Bootstrapping was used to assess, quantify, and adjust for model optimism. Model performance was evaluated using AUC, precision and recall metrics. Brier scores for accuracy of probabilistic predictions ranged from 0 to 1 (0 is perfect discrimination).

The testing showed model performance for prediction windows are 0.78 for AUC (95% CI), 0.71 for Recall (sensitivity), 0.195 for Brier score, and 0.68 for precision (true positive 893, false positive 417, false negative 367, true negative 966).

Based on weighing in the random forest, the top 10 pro-flare attributes were CRP, swollen joint count (SJC), tender joint count (TJC), HAQ, DAS28, morning stiffness, gout, MCTD, OA, duration; while top 10 anti-flare attributes were cDMARDs+Bio, cDMARDs+steroid+NSAIDs, stable on HAQ, on morning stiffness, on SJC, medicine on COMBs, cDMARDs+TCM, stable on TJC, on ESR, income at 100-200k (Fig.1). The top weighing COMBs for pro-flaring were gout (0.81), MRD (0.75), OA (0.56), AS (0.48). The monotherapies with either Bio or NSAIDs, or steroid, or TCM was pro-flare; while with cDMARDs was anti-flare (-0.21).

Figure 1.

Conclusion:

The attempt to develop a machine learning algorithm for RA flare prediction is successful. The discrimination was acceptable. The attributes of both pro-flare and anti-flare are identified, which may inspire the proactive intervention.

Acknowledgments:

SSDM was developed by Shanghai Gothic Internet Technology Co., Ltd.

Disclosure of Interests:

None declared

0761 Independent Components Analysis And Graph Theoretical Analysis In Patients With Narcolepsy

Introduction

To evaluate resting state functional connectivity and topological properties of brain network in narcolepsy compared with healthy controls.

Methods

Resting state fMRI was performed in 26 adult narcolepsy patients and 30 matched healthy controls. MRI data was first analyzed by group independent component analysis, then a graph theoretical method was applied to evaluate topological properties within whole brain. Small-world network parameters and nodal topological properties were measured. Altered topological properties in brain areas between groups were selected as ROI-seeds, then functional connectivity among these ROI-seeds were compared between groups. Partial correlation analysis was performed to evaluate the relationship between sleepiness severity and functional connectivity or topological properties in the narcolepsy.

Results

21 independent components out of 48 components were obtained. Compared with healthy controls, narcolepsy exhibited a significant decreased functional connectivity within the executive and salience network, while increased functional connectivity in bilateral frontal lobe within executive network can be detected in narcolepsy. There were no differences in small-world network properties between narcolepsy and healthy controls. The altered brain areas in nodal topological properties were mainly located in inferior frontal cortex, basal ganglia, anterior cingulate, sensory cortex, supplementary motor cortex and visual cortex between groups. In the partial correlation analysis, nodal topological properties in putamen, anterior cingulate and sensory cortex as well as functional connectivity between these brain regions were correlated with the severity of sleepiness (sleep latency, REM sleep latency and ESS) among narcolepsy.

Conclusion

Altered connectivity within executive network and salience network were found in narcolepsy. Functional connection changes between left frontal cortex and left caudate nucleus may be one of the parameters describing the severity of narcolepsy. Nodal topological properties alterations in left putamen and left posterior cingulate, changes in functional connectivity between left supplementary motor area and right occipital as well as changes in functional connectivity between left anterior cingulate gyrus and bilateral postcentral gyrus can be considered to be a specific indicator for evaluating the severity of narcolepsy.

Support

National Natural Science Foundation of China (81700088)National Program on Key Basic Research Project of China (973 Program, 2015CB856405)

0009 Anti-Streptococcal Antibodies in Chinese Patients with Type -1 Narcolepsy

Introduction

Narcolepsy type 1 (NT1) is considered to be an autoimmune disease, and streptococcal infection may be an environmental trigger. However, previous studies from Asian narcolepsy patients did not reveal elevated anti-streptolysin O [ASO]. The aim is to investigate whether large sample Chinese patients with NT1 have an increase in antistreptococcal antibody titers.

Methods

A total of 214 narcolepsy patients and 360 healthy controls were recruited. All patients were DQB1*0602 positive with clear-cut cataplexy or had low CSF hypocretin-1. Participants were tested for ASO and anti DNAse B [ADB]. These patients were divided into five groups according to disease duration, including 29 patients less than 3 months; 25 from 3 months to 1 year; 40 from 1 to 3 years; 61 from 3 to 10 years and 59 patients over 10 years. Comparison was also made between children and adults with age matched controls, respectively.

Results

There were no significant differences between patients and healthy controls in regard to both ASO ≥ 200 IU (19.2% vs. 16.9%, p = 0.50) and ADB≥480IU (9.8% vs. 10.3%, p = 0.86). For children narcolepsy patients, ASO positive rates(19.8% vs. 18%, p = 0.68) and ADB positive rates(10.4% vs. 12%, p = 0.72) had no differences compared to age matched controls. And no difference was observed in adult narcolepsy patients either, with ASO positive rates (18.5% vs. 13.8%, p = 0.39) and ADB positive rates (9.3% vs. 5.3%, p = 0.42) compared to age matched controls, respectively. ASO (ADB) positive rates had no significant differences among different disease duration groups(p= 0.55, 0.9).

Conclusion

It is indicated that positive rates of ASO and ADB were not significantly different between Chinese patients with NT1 and healthy controls, including recent onset cases and children.

Support

The study was supported by the National Natural Science Foundation of China (No. 81420108002 and NO. 81570083)

Electrical molecular switch addressed by chemical stimuli

We demonstrate that the conductance switching of benzo-bis(imidazole) molecules upon protonation depends on the lateral functional groups. The protonated H-substituted molecule shows a higher conductance than the neutral one (Gpro > Gneu), while the opposite (Gneu > Gpro) is observed for a molecule laterally functionalized by amino-phenyl groups. These results are demonstrated at various scale lengths: self-assembled monolayers, tiny nanodot-molecule junctions and single molecules. From ab initio theoretical calculations, we conclude that for the H-substituted molecule, the result Gpro > Gneu is correctly explained by a reduction of the LUMO-HOMO gap, while for the amino-phenyl functionnalized molecule, the result Gneu > Gpro is consistent with a shift of the HOMO, which reduces the density of states at the Fermi energy.