Machine learning-based test smell detection.

Test smells are symptoms of sub-optimal design choices adopted when developing test cases. Previous studies have proved their harmfulness for test code maintainability and effectiveness. Therefore, researchers have been proposing automated, heuristic-based techniques to detect them. However, the performance of these detectors is still limited and dependent on tunable thresholds. We design and experiment with a novel test smell detection approach based on machine learning to detect four test smells. First, we develop the largest dataset of manually-validated test smells to enable experimentation. Afterward, we train six machine learners and assess their capabilities in within- and cross-project scenarios. Finally, we compare the ML-based approach with state-of-the-art heuristic-based techniques. The key findings of the study report a negative result. The performance of the machine learning-based detector is significantly better than heuristic-based techniques, but none of the learners able to overcome an average F-Measure of 51%. We further elaborate and discuss the reasons behind this negative result through a qualitative investigation into the current issues and challenges that prevent the appropriate detection of test smells, which allowed us to catalog the next steps that the research community may pursue to improve test smell detection techniques.

Unveiling the Electronic Structure of Pseudotetragonal WO3 Thin Films.

WO3 is a 5d compound that undergoes several structural transitions in its bulk form. Its versatility is well-documented, with a wide range of applications, such as flexopiezoelectricity, electrochromism, gating-induced phase transitions, and its ability to improve the performance of Li-based batteries. The synthesis of WO3 thin films holds promise in stabilizing electronic phases for practical applications. However, despite its potential, the electronic structure of this material remains experimentally unexplored. Furthermore, its thermal instability limits its use in certain technological devices. Here, we employ tensile strain to stabilize WO3 thin films, which we call the pseudotetragonal phase, and investigate its electronic structure using a combination of photoelectron spectroscopy and density functional theory calculations. This study reveals the Fermiology of the system, notably identifying significant energy splittings between different orbital manifolds arising from atomic distortions. These splittings, along with the system's thermal stability, offer a potential avenue for controlling inter- and intraband scattering for electronic applications.

Final results of the real-life observational VICTOR-6 study on metronomic chemotherapy in elderly metastatic breast cancer (MBC) patients.

Nowadays, treatment of metastatic breast cancer (MBC) has been enriched with novel therapeutical strategies. Metronomic chemotherapy (mCHT) is a continuous and frequent administration of chemotherapy at a lower dose and so whit less toxicity. Thus, this strategy could be attractive for elderly MBC patients. Aim of this analysis is to provide insights into mCHT's activity in a real-life setting of elderly MBC patients. Data of patients ≥ 75 years old included in VICTOR-6 study were analyzed. VICTOR-6 is a multicentre, Italian, retrospective study, which collected data on mCHT in MBC patients treated between 2011 and 2016. A total of 112 patients were included. At the beginning of mCHT, median age was 81 years (75-98) and in 33% of the patients mCHT was the first line choice. Overall Response Rate (ORR) and Disease Control Rate (DCR) were 27.9% and 79.3%, respectively. Median PFS ranged between 7.6 and 9.1 months, OS between 14.1 and 18.5 months. The most relevant toxicity was the hematological one (24.1%); severe toxicity (grade 3-4) ranged from 0.9% for skin toxicity up to 8% for hematologic one. This is a large study about mCHT in elderly MBC patients, providing insights to be further investigated in this subgroup of frail patients.

Giant Biquadratic Exchange in 2D Magnets and Its Role in Stabilizing Ferromagnetism of NiCl_{2} Monolayers.

Two-dimensional (2D) van der Waals (vdW) magnets provide an ideal platform for exploring, on the fundamental side, new microscopic mechanisms and for developing, on the technological side, ultracompact spintronic applications. So far, bilinear spin Hamiltonians have been commonly adopted to investigate the magnetic properties of 2D magnets, neglecting higher order magnetic interactions. However, we here provide quantitative evidence of giant biquadratic exchange interactions in monolayer NiX_{2} (X=Cl, Br and I), by combining first-principles calculations and the newly developed machine learning method for constructing Hamiltonian. Interestingly, we show that the ferromagnetic ground state within NiCl_{2} single layers cannot be explained by means of the bilinear Heisenberg Hamiltonian; rather, the nearest-neighbor biquadratic interaction is found to be crucial. Furthermore, using a three-orbitals Hubbard model, we propose that the giant biquadratic exchange interaction originates from large hopping between unoccupied and occupied orbitals on neighboring magnetic ions. On a general framework, our work suggests biquadratic exchange interactions to be important in 2D magnets with edge-shared octahedra.

Metronomic chemotherapy (mCHT) in metastatic triple-negative breast cancer (TNBC) patients: results of the VICTOR-6 study.

PURPOSE: Triple-negative breast cancer (TNBC) represents a subtype of breast cancer which lacks the expression of oestrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER2): TNBC accounts for approximately 20% of newly diagnosed breast cancers and is associated with younger age at diagnosis, greater recurrence risk and shorter survival time. Therapeutic options are very scarce. Aim of the present analysis is to provide further insights into the clinical activity of metronomic chemotherapy (mCHT), in a real-life setting. METHODS: We used data included in the VICTOR-6 study for the present analysis. VICTOR-6 is an Italian multicentre retrospective cohort study, which collected data of metastatic breast cancer (MBC) patients who have received mCHT between 2011 and 2016. Amongst the 584 patients included in the study, 97 were triple negative. In 40.2% of the TNBC patients, mCHT was the first chemotherapy treatment, whereas 32.9% had received 2 or more lines of treatment for the metastatic disease. 45.4% out of 97 TNBC patients received a vinorelbine (VRL)-based regimen, which resulted in the most used type of mCHT, followed by cyclophosphamide (CTX)-based regimens (30.9%) and capecitabine (CAPE)-based combinations (22.7%). RESULTS: Overall response rate (ORR) and disease control rate (DCR) were 17.5% and 64.9%, respectively. Median progression free survival (PFS) and overall survival (OS) were 6.0 months (95% CI: 4.9-7.2) and 12.1 months (95% CI: 9.6-16.7). Median PFS was 6.9 months for CAPE-based regimens (95% CI: 5.0-18.4), 6.1 months (95% CI: 4.0-8.9) for CTX-based and 5.3 months (95% CI: 4.1-9.5) for VRL-based ones. Median OS was 18.2 months (95% CI: 9.1-NE) for CAPE-based regimens and 11.8 months for VRL- (95% CI: 9.3-16.7 and CTX-based ones (95%CI: 8.7-52.8). Tumour response, PFS and OS decreased proportionally in later lines. CONCLUSION: This analysis represents the largest series of TNBC patients treated with mCHT in a real-life setting and provides further insights into the advantages of using this strategy even in this poor prognosis subpopulation.

Metronomic chemotherapy for advanced breast cancer patients in the real world practice: Final results of the VICTOR-6 study.

Metronomic chemotherapy (mCHT) refers to the minimum biologically effective dose of a chemotherapy agent given as a continuous dosing regimen, with no prolonged drug-free breaks, that leads to antitumor activity. Aim of the present study is to describe the use of mCHT in a retrospective cohort of metastatic breast cancer (MBC) patients in order to collect data regarding the different types and regimens of drugs employed, their efficacy and safety. Between January 2011 and December 2016, data of 584 metastatic breast cancer patients treated with mCHT were collected. The use of VRL-based regimens increased during the time of observation (2011: 16.8% - 2016: 29.8%), as well as CTX-based ones (2011: 17.1% - 2016: 25.6%), whereas CAPE-based and MTX-based regimens remained stable. In the 1st-line setting, the highest ORR and DCR were observed for VRL-based regimens (single agent: 44% and 88%; combination: 36.7% and 82.4%, respectively). Assuming VRL-single agent as the referee treatment (median PFS: 7.2 months, 95% CI: 5.3-10.3), the longest median PFS were observed in VRL-combination regimens (9.5, 95%CI 88.8-11.3, HR = 0.72) and in CAPE-single agent (10.7, 95%CI 8.3-15.8, HR = 0.70). The VICTOR-6 study provides new data coming from the real-life setting, by adding new information regarding the use of mCHT as an option of treatment for MBC patients.

Metronomic oral vinorelbine for the treatment of advanced non-small cell lung cancer: a multicenter international retrospective analysis.

PURPOSE: Metronomic oral vinorelbine (MOV) could be a treatment option for unfit patients with advanced non-small cell lung cancer (NSCLC) based on its safety profile and high patient compliance. METHODS: We retrospectively collected data on 270 patients [median age 76 (range 48-92) years, M/F 204/66, PS 0 (27)/1 (110)/≥ 2 (133), median of 3 serious comorbidities] with stage IIIB-IV NSCLC treated with MOV as first (T1) (67%), second (T2) (19%) or subsequent (T3) (14%) line. Schedules consisted of vinorelbine 50 mg (138), 40 mg (68) or 30 mg (64) three times a week continuously. RESULTS: Patients received an overall median of 6 (range 1-25) cycles with a total of 1253 cycles delivered. The overall response rate was 17.8% with 46 partial and 2 complete responses and 119 patients (44.1%) experienced stable disease > 12 weeks with an overall disease control rate of 61.9%. Median overall time to progression was 5 (range 1-21) months [T1 7 (1-21), T2 5.5 (1-19) and T3 4 (1-19) months] and median overall survival 9 (range 1-36) months [T1 10 (1-31), T2 8 (1-36) and T3 6.5 (2-29) months]. Treatment was extremely well tolerated with 2% (25/1253) G3/4 toxicity (mainly G3 fatigue and anemia) and no toxic deaths. We observed the longer OS 14 (range 7-36) months in a subset of squamous NSCLC patients receiving immunotherapy after metronomic oral vinorelbine. CONCLUSION: We confirmed MOV as an extremely safe treatment in a large real world population of advanced NSCLC with an interesting activity mainly consisting of long-term disease stabilization. We speculate the possibility of a synergistic effect with subsequent immunotherapy.

Nutritional status and intrarenal arterial stiffness in cardiorenal syndrome: a pilot study.

OBJECTIVE: Cardio-Renal Syndrome (CRS) is a condition, which is more frequently observed in clinical practice. The aim of this study is to explore nutritional status and intrarenal arterial stiffness in patients affected by CRS. PATIENTS AND METHODS: 14 consecutive CRS patients, screened for anthropometry, biochemistry, nutritional and metabolic status underwent renal Doppler ultrasound and whole-body bioimpedance spectroscopy (BIS). RESULTS: We found a positive correlation between phase angle (PA) and CKD-EPI and MDRD (p=0.011 and p=0.007), and between body mass index and renal resistive index (RRI) (p=0.002). Finally, we found a negative correlation between fat-free mass and RRI (p=0.024). CONCLUSIONS: Body composition assessment may improve the care of patients with chronic kidney disease (CKD). Also, BIS may help identify changes in hydration status in CKD patients resulting as a significant predictor of mortality.

Continuation or reintroduction of bevacizumab beyond progression to first-line therapy in metastatic colorectal cancer: final results of the randomized BEBYP trial.

BACKGROUND: The combination of bevacizumab with fluorouracil-based chemotherapy is a standard first-line treatment option in metastatic colorectal cancer (mCRC). We studied the efficacy of continuing or reintroducing bevacizumab in combination with second-line chemotherapy after progression to bevacizumab-based first-line therapy. PATIENTS AND METHODS: In this phase III study, patients with mCRC treated with fluoropyrimidine-based first-line chemotherapy plus bevacizumab were randomized to receive in second-line mFOLFOX-6 or FOLFIRI (depending on first-line regimen) with or without bevacizumab. The primary end point was progression-free survival. To detect a hazard ratio (HR) for progression of 0.70 with an α and ß error of 0.05 and 0.20, respectively, 262 patients were required. RESULTS: In consideration of the results of the ML18147 trial, the study was prematurely stopped. Between April 2008 and May 2012, a total of 185 patients were randomized. Bevacizumab-free interval was longer than 3 months in 43% of patients in chemotherapy alone arm and in 50% of patients in the bevacizumab arm. At a median follow-up of 45.3 months, the median progression-free survival was 5.0 months in the chemotherapy group and 6.8 months in the bevacizumab group [adjusted HR = 0.70; 95% confidence interval (CI) 0.52-0.95; stratified log-rank P = 0.010]. Subgroup analyses showed a consistent benefit in all subgroups analyzed and in particular in patients who had continued or reintroduced bevacizumab. An improved overall survival was also observed in the bevacizumab arm (adjusted HR = 0.77; 95% CI 0.56-1.06; stratified log-rank P = 0.043). Responses (RECIST 1.0) were similar in the chemotherapy and bevacizumab groups (17% and 21%; P = 0.573). Toxicity profile was consistent with previously reported data. CONCLUSIONS: This study demonstrates that the continuation or the reintroduction of bevacizumab with second-line chemotherapy beyond first progression improves the outcome and supports the use of this strategy in the treatment of mCRC. ClinicalTrials.gov number: NCT00720512.

A phase II study of erlotinib in combination with bevacizumab versus chemotherapy plus bevacizumab in the first-line treatment of advanced non-squamous non-small cell lung cancer.

BACKGROUND: Molecularly targeted agents for non-small cell lung cancer (NSCLC) can provide similar efficacy to chemotherapy without chemotherapy-associated toxicities. Combining two agents with different modes of action could further increase the efficacy of these therapies. The TASK study evaluated the efficacy and safety of the epidermal growth factor receptor tyrosine kinase inhibitor erlotinib in combination with the anti-angiogenic agent bevacizumab as first-line therapy in unselected, advanced non-squamous NSCLC patients. METHODS: Patients were recruited from December 2007 to September 2008. Planned sample size was 200 patients, a total of 124 patients were randomized. Patients were randomized using a minimization algorithm 1:1 to receive bevacizumab (iv 15 mg/kg day 1 of each 21-day cycle) plus chemotherapy (gemcitabine/cisplatin or carboplatin/paclitaxel standard doses, 4-6 cycles) (BC arm) or bevacizumab plus erlotinib (p.o. 150 mg/day; BE arm) until disease progression or unacceptable toxicity. The primary endpoint was progression-free survival (PFS). If the hazard ratio (HR) of PFS for BE relative to BC was above 1.25 at the pre-planned interim analysis in favor of BC, the study would be re-evaluated. Secondary endpoints included overall survival, response rate and safety. RESULTS: All randomized patients (n = 63 BE; n = 61 BC) were evaluated for the efficacy analyses. At the updated interim analysis, median PFS was 18.4 weeks (95% confidence interval [CI] 17.0-25.1) versus 25.0 weeks (95% CI 20.6-[not reached]) for BE versus BC, respectively (HR for death or disease progression, BE relative to BC, 2.05, p = 0.0183). The incidence of death was 19% for BE treatment compared with 11.5% for BC treatment. The HR for PFS at the updated interim analysis was above 1.25, therefore patients on the BE arm were permitted to change arms or switch to another drug and the study was terminated. Adverse events reported were as expected. CONCLUSIONS: The TASK study did not show a benefit in terms of PFS for the combination of erlotinib with bevacizumab in unselected first-line advanced non-squamous NSCLC compared with chemotherapy plus bevacizumab.

Predictor factors for renal outcome in renal artery stenosis.

BACKGROUND: Atherosclerotic ischemic renal disease is a frequent cause of end-stage renal failure. Correction of renal artery stenosis (RAS) may fail to stabilize or improve renal function. AIMS OF THE STUDY: Carotid and aortic Intima media thickness (IMT), resistance renal resistance index (RI), arterial blood pressure (BP), serum creatinine (SCr), creatinine clearance (CrCl), proteinuria and uricemia were considered as possible predictive factors and measured before renal-artery stenosis correction and during 12 months follow-up. MATERIALS AND METHODS: we performed an observational study on a total of 55 patients to find predictive factors of the outcome of renal function after renal percutaneous transluminal angioplasty and stenting (RPTAs). RESULTS: We found that uricemia, proteinuria and IR were higher at baseline in patients who worsened renal function after revascularization. CONCLUSIONS: The identification of predictive factors (uricemia; proteinuria and RI) of chronic kidney disease (CKD) progression in patients with RAS undergone revascularization could be useful to predict renal long term outcome and to select patients that really could benefit of this.

First-line chemotherapy with planned sequential administration of cisplatin/gemcitabine followed by docetaxel in elderly 'unfrail' patients with advanced non-small-cell lung cancer: a multicenter phase II study.

PURPOSE: The role of cisplatin in the first-line treatment for elderly advanced non-small-cell lung cancer is not completely defined. We previously reported in this subset of patients an interesting efficacy and tolerability of a sequential schedule of gemcitabine followed by docetaxel. METHODS: Patients aged ≥70 years and with Eastern Cooperative Oncology Group performance status 0 or 1 received cisplatin 60 mg/m(2) on Day 1 and gemcitabine 1,000 mg/m(2) on Day 1 and 8 every 3 weeks for 3 courses followed by 3 courses of docetaxel 37.5 mg/m(2) on Day 1 and 8 every 3 weeks, provided there was no evidence of disease progression. Patients were excluded if considered 'frail' according to the Multidimensional Geriatric Assessment. The main objective of the study was the 4-month progression-free survival rate. Simon's two-stage minimax design was applied to calculate the sample size. RESULTS: After 30 patients were enroled into the study, the 4-month progression-free survival rate was 53.3 % and the study was closed at the first stage for futility; the overall response rate was 16.7 %; the median time to progression and median duration of survival were 5.1 and 8.6 months, respectively; the 1-year survival rate was 30 %. CONCLUSION: The incorporation of cisplatin in a sequential schedule of gemcitabine followed by docetaxel is feasible but did not yield a substantial advantage to deserve further investigations.

Phase II trial of single-agent oral vinorelbine in elderly (> or =70 years) patients with advanced non-small-cell lung cancer and poor performance status.

BACKGROUND: Elderly patients with advanced non-small-cell lung cancer (NSCLC) with poor performance status (PS) are a special population requiring particular attention. Single-agent oral vinorelbine could be an attractive option. PATIENTS AND METHODS: A total of 43 patients with stage IIIB-IV NSCLC and Eastern Cooperative Oncology Group (ECOG) PS of two or more with good functional status were prospectively recruited. Oral vinorelbine was administered at the dose of 60 mg/m(2) on days 1-8 every 3 weeks. Primary end points were response rate and safety. RESULTS: Overall response rate was 18.6% with 8 partial responses; 18 of 43 (41.8%) experienced stable disease lasting >12 weeks and 17 of 43 (39.6%) disease progression for an overall clinical benefit of 60.4%. Median time to progression was 4.0 (range 2-22) months and median overall survival 8.0 (range 3-35) months. Treatment was well tolerated. Of 187 cycles, we did not observe any grade 3/4 toxicity with the exception of a single not-febrile G3 neutropenia. Regardless of severity, main toxic effects observed were nausea in 48.1% and vomiting in 22.9% of patients, anemia in 43.2%, fatigue in 32.6% and leukopenia in 23.2%. CONCLUSION: Single-agent oral vinorelbine is extremely safe in elderly patients with advanced NSCLC and ECOG PS of two or more and may represent a valid option in this very special population.

A multicenter phase II study of the combination of oxaliplatin, irinotecan and capecitabine in the first-line treatment of metastatic colorectal cancer.

The triple drug combination consisting of irinotecan, oxaliplatin and 5-fluorouracil (FOLFOXIRI) has demonstrated higher activity and efficacy compared to the doublet FOLFIRI. 5-Fluorouracil could be substituted in FOLFOXIRI regimen by capecitabine, an oral fluoropyrimidine with similar efficacy. Recently, a dose-finding trial has demonstrated the feasibility of the combination of irinotecan, oxaliplatin and capecitabine (XELOXIRI) and established their recommended doses. The aim of this study was to evaluate the activity of XELOXIRI. A total of 36 patients with unresectable metastatic colorectal cancer received irinotecan 165 mg m(-2) and oxaliplatin 85 mg m(-2) on day 1 plus capecitabine 2000 mg m(-2) per day orally in two doses from day 1 to day 7, every 2 weeks. Grade 3-4 toxicities were infrequent, expect for neutropenia and diarrhoea, which were each observed in 30% of patients. Two complete and twenty-two partial responses were obtained, corresponding to an overall response rate of 67% (95% CI 51.4-82%). After a median follow-up of 17.7 months, the median progression-free and overall survival were 10.1 and 17.9 months, respectively. The substitution of 5-fluorouracil with capecitabine, in combination with irinotecan and oxaliplatin, is feasible and does not impair the activity of the regimen. However, the XELOXIRI combination is associated with a high incidence of diarrhoea and, therefore, should be considered as a not preferable alternative to FOLFOXIRI.

The CAP-CR study: direct medical costs in Italian metastatic colorectal cancer patients on first-line infusional 5-fluorouracil or oral capecitabine.

AIM: To describe the healthcare resource consumption of metastatic colorectal cancer (MCRC) patients in the Italian healthcare setting. METHODS: A retrospective chart analysis estimating direct medical costs of first-line infusional 5-Fluorouracil (5-FU) or oral Capecitabine (CAP), associated or not with other chemotherapies, from the Italian Healthcare Service (IHCS) and Hospital (H) perspectives. RESULTS: 202 subjects were analysed. CAP patients (N=66) were older, with a more compromised clinical status and received less chemotherapy agents in association than 5-FU patients (N=136). From the IHCS perspective, mean total costs per patient were 12,029 euro and 5,781 euro in the 5-FU and CAP arms respectively; 7,338 euro and 4,688 euro from the H perspective. The infusional administration route of 5-FU was a cost driver from both perspectives. Sensitivity analyses found the results to be robust to variations in base case parameters. CONCLUSIONS: Management of MCRC by oral chemotherapies may be an economically advantageous option to both IHCS and hospitals.

First line chemotherapy with planned sequential administration of gemcitabine followed by docetaxel in elderly advanced non-small-cell lung cancer patients: a multicenter phase II study.

This multicenter phase II study evaluated, in chemonaive patients with stage IIIB-IV NSCLC, age >or=70 and with a performance status 0-2, the activity, efficacy and tolerability of planned sequential administration of gemcitabine 1200 mg m(-2) on days 1 and 8 every 3 weeks for three courses followed by three cycles of docetaxel 37.5 mg m(-2) on days 1 and 8 every 3 weeks, provided there was no evidence of disease progression. A total of 56 patients entered the study. According to intention-to-treat analysis, the objective response rate was 16.0% (95% CI 7.6-28.3%); 23 patients (41.0%) had stable disease and 24 patients (43%) had progressive disease. Five patients who had a stable disease after three courses of gemcitabine obtained a conversion to partial response by docetaxel. Median time to progression was 4.8 months (95% CI 3.6-6.0 months) and median duration of survival was 8.0 months (95% CI 5.6-10.5 months). The 1-year survival rate was 34%. No grade 4 haematological toxicity was observed and grade 3 neutropenia and thrombocytopenia were reported in 5.4 and 3.6% of the patients, respectively. Grade 3/4 mucositis and grade 3 diarrhoea, both occurred in 3.6% of the patients and grade 3 asthenia was observed in 9% of patients. One patient reported a grade 4 skin toxicity. No treatment-related deaths occurred. Sequential gemcitabine and docetaxel is a well-tolerated and effective regimen in elderly advanced NSCLC patients.

Clinical significance and treatment of skin rash from erlotinib in non-small cell lung cancer patients: results of an Experts Panel Meeting.

Advances in the knowledge of tumor biology and mechanisms of oncogenesis has granted the singling out of several molecular targets for non-small cell lung cancer (NSCLC) treatment. Among these targets, epidermal growth factor receptor (EGFR), or HER1, has received particular attention in lung cancer treatment. Erlotinib, an orally available inhibitor of EGFR tyrosine kinase in a phase III randomized placebo-controlled trial (BR.21), has been proven to prolong survival in NSCLC patients after first or second line chemotherapy. Skin rash is the most common adverse event associated with erlotinib treatment and it is often cause of negative impact on patients' quality of life. There is no specific treatment for this toxicity due to the lack of evidence-based data and recommendations. A panel of Italian oncologists, who had participated to clinical trials and to the Expanded Access Program for erlotinib in NSCLC treatment, and dermatologists with experience with cutaneous toxicity from EGFR inhibitors, attended a Meeting held in Rome on December 2006 to discuss skin rash from erlotinib and to provide suggestions for managing this frequent side-effect.

Urine chemokines: biomarkers of human lupus nephritis?

Lupus nephritis is characterized by intrarenal inflammation. Leukocytes trafficking from peripheral blood into affected tissues spaces represent an important factor in the development of many renal diseases. During the past few years has been attributed the crucial role of a family of chemotactic cytokines--the chemokines--in this process. In the course of renal diseases, the infiltration of monocytes/macrophages and T cells into kidneys represent an important role in progressive interstitial fibrosis and the progression of chronic renal failure. In this review, we summarize the in vitro and in vivo data on chemokines and chemokine receptors in kidney diseases, with a special focus on urine chemokine measurement as possible biomarker of human lupus nephritis.