Unexpected discovery of renal mass in a patient with granulomatosis with polyangiitis: accidental or inevitable?

Granulomatosis with polyangiitis (GPA) is an uncommon disorder that mainly involves the upper and lower respiratory tract and kidney, presenting as sinusitis, saddle nose, otitis media, pulmonary nodule and cavity, rapidly progressive glomerulonephritis. It also affects skin, eye, heart, joint and nervous system. Renal involvement in GPA is commonly manifested as necrotising glomerulonephritis, while renal mass is very rare. We herein present two hospitalised cases with fever, pulmonary cavity and renal mass. Clinical course and examinations of the cases, from symptoms to diagnosis, will be discussed in detail, along with a relevant literature review of this unusual renal manifestation.

Leflunomide: Traditional immunosuppressant with concurrent antiviral effects.

Leflunomide is a classic disease-modifying anti-rheumatic drug that is widely used to treat autoimmune diseases. Studies also show its antiviral effects in in vitro and/or in vivo experiments. Considering glucocorticoids, immunosuppressants and newly emerged antibodies commonly used in autoimmune diseases and autoinflammatory disorders bring risk of infection such as viral infection, leflunomide with combination of anti-viral and immunosuppressive features to maintain the balance between infection and anti-inflammation are attractive. Here we summarize the actions and mechanisms of leflunomide in immunoregulatory and antiviral effects.

A randomized, controlled trial on fenofibrate in primary biliary cholangitis patients with incomplete response to ursodeoxycholic acid.

Introduction: About one-third of primary biliary cholangitis (PBC) patients do not exhibit complete response to ursodeoxycholic acid (UDCA). Some of these patients were reported to benefit from the combination therapy of fibrates and UDCA, but more clinical evidence is required. In this study, we conducted a randomized, controlled trial on the safety and efficacy of fenofibrate in the treatment of patients with PBC. Methods: Forty-eight PBC patients with incomplete response to UDCA were enrolled and randomly assigned to two groups (24 in the experiment group and 24 in the control group). For the experimental group, the patients were administered 13-15 mg/kg/day UDCA in combination with 200 mg/day fenofibrate. For the control group, the patients continued to receive UDCA at 13-15 mg/kg/day. The patients were followed up for at least 12 months. The serum levels of alkaline phosphatase (ALP), gamma-glutamyl transferase (γ-GT), aspartate aminotransferase (AST), and other biochemical parameters were measured at 3, 6, and 12 months during the trial to assess patient conditions. Results: At 12 months, 20.8% of the patients in the experimental group had all three indexes of serum ALP, γ-GT, and total bilirubin normalized, while 0% of patients in the control group reached the primary outcome (difference, 20.8 percentage points; 95% CI, 4.6-37.0). 54.2% of the patients had normal ALP levels in the experimental group and 4.2% in the control group (difference, 50 percentage points; 95% CI, 28.5-71.5). The experimental group had greater improvement of ALP (p < 0.001) and IgG (p = 0.026) than the control group. The biochemical indexes of the patients in the experimental group also significantly improved during the treatment of fenofibrate. Conclusion: Addition of fenofibrate can improve biochemical indexes of PBC patients who had an incomplete response to UDCA. Reversible elevation of serum creatine and transaminases is observed in some patients.The trial was registered in the Chinese Clinical Trial Registry (ChiCTR) as ChiCTR1800020160 (protocol available online: http://www.chictr.org.cn/showproj.aspx?proj=32443).

Mesenchymal stem cell-based treatment in autoimmune liver diseases: underlying roles, advantages and challenges.

Autoimmune liver disease (AILD) is a series of chronic liver diseases with abnormal immune responses, including autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC). The treatment options for AILD remain limited, and the adverse side effects of the drugs that are typically used for treatment frequently lead to a low quality of life for AILD patients. Moreover, AILD patients may have a poor prognosis, especially those with an incomplete response to first-line treatment. Mesenchymal stem cells (MSCs) are pluripotent stem cells with low immunogenicity and can be conveniently harvested. MSC-based therapy is emerging as a promising approach for treating liver diseases based on their advantageous characteristics of immunomodulation, anti-fibrosis effects, and differentiation to hepatocytes, and accumulating evidence has revealed the positive effects of MSC therapy in AILD. In this review, we first summarize the mechanisms, safety, and efficacy of MSC treatment for AILD based on work in animal and clinical studies. We also discuss the challenges of MSC therapy in clinical applications. In summary, although promising data from preclinical studies are now available, MSC therapy is currently far for being applied in clinical practice, thus developing MSC therapy in AILD is still challenging and warrants further research.

Elemental Fluorine Detection by Dielectric Barrier Discharge Coupled to Nanoelectrospray Ionization Mass Spectrometry for Nontargeted Analysis of Fluorinated Compounds.

The growing use of fluorochemicals has elevated the need for nontargeted detection of unknown fluorinated compounds and transformation products. Elemental mass spectrometry (MS) coupled to chromatography offers a facile approach for such analyses by using fluorine as an elemental tag. However, efficient ionization of fluorine has been an ongoing challenge. Here, we demonstrate a novel atmospheric-pressure elemental ionization method where fluorinated compounds separated by gas chromatography (GC) are converted to Na2F+ for nontargeted detection. The compounds are first introduced into a helium dielectric barrier discharge (DBD) for breakdown. The plasma products are subsequently ionized by interaction with a nanoelectrospray ionization (nano-ESI) plume of sodium-containing aqueous electrolytes. Our studies point to HF as the main plasma product contributing to Na2F+ formation. Moreover, the results reveal that Na2F+ is largely formed by the ion-neutral reaction between HF and Na2A(NaA)n+, gas-phase reagent ions produced by nano-ESI where A represents the anion of the electrolyte. Near-uniform fluorine response factors are obtained for a wide range of compounds, highlighting good efficiency of HF formation by DBD regardless of the chemical structure of the compounds. Detection limits of 3.5-19.4 pg of fluorine on-column are obtained using the reported GC-DBD-nano-ESI-MS. As an example of nontargeted screening, extractions from oil-and-water-repellent fabrics are analyzed via monitoring Na2F+, resulting in detection of a fluorinated compound on a clothing item. Notably, facile switching of the ion source to atmospheric-pressure chemical ionization with the exact same chromatographic method allows identification of the detected compound at the flagged retention time.

High-Sensitivity Elemental Mass Spectrometry of Fluorine by Ionization in Plasma Afterglow.

Fluorine elemental analysis using inductively coupled plasma mass spectrometry (ICPMS) is challenging because of low F ionization efficiency in the plasma and severe isobaric interferences. Notably, there is an increasing demand for ppb level fluorine measurements due to the rising importance of fluorinated compounds in pharmaceutical, environmental, and food analyses. Here, we report a new elemental ionization method where fluorinated analytes are introduced into an ICP to produce NaF followed by Na2F+ formation in the atmospheric-pressure plasma afterglow. The new method offers over 2 orders of magnitude improved sensitivities (180-500 cps/ppb versus 1.6-3.2 cps/ppb) for F detection. This approach also yields compound-independent F response for quantitation without compound-specific standards. Detection limits of ∼50 ppb F are attained using a single-quadrupole instrument without discrimination against isobaric interferences. Similar LODs are achievable only by isobaric interference reduction in ICPMS/MS. Importantly, the new approach offers facile interfacing to molecular MS instruments where LODs can be further improved via MS/MS and high-resolution MS techniques. The tolerance to matrix is demonstrated by quantitation of fluoride in infant formula, yielding recoveries of 86%-98% with repeatabilities of 3.5-6.3 RSD%.

Atmospheric-Pressure Dielectric Barrier Discharge as an Elemental Ion Source for Gas Chromatographic Analysis of Organochlorines.

Atmospheric-pressure dielectric barrier discharge (AP-DBD) plasma has emerged in recent years as a versatile plasma for molecular ionization and elemental spectroscopy. However, its capabilities as an elemental ion source have been less explored, partly because of difficulties in the detection of positive elemental ions from this low-gas-temperature plasma. In this work, we investigate the detection of negative elemental ions to enable elemental mass spectrometry (MS) using AP-DBD. A gas chromatograph is coupled to a helium AP-DBD apparatus and positioned in front of an atmospheric-pressure-sampling mass spectrometer with no modifications to the ion sampling interface. We demonstrate that Cl- ions are detected with a compound-independent efficiency, enabling elemental quantification of organochlorines. Further, addition of oxygen at low concentration (11 ppm, v/v) to the helium plasma improves the analytical performance by reducing postcolumn peak broadening, whereas high oxygen concentrations (>110 ppm, v/v) lead to loss of the compound-independent response. The optimized GC-AP-DBD-MS setup shows close to 2 orders of magnitude of linearity for its compound-independent Cl response and offers detection limits of 0.5-1 pg of Cl on column (0.6 pg/s), suitable for analysis of organochlorines in food samples. We demonstrate this capability by analyzing orange juice spiked with pesticides at 9 µg/L and a single internal standard. Importantly, we demonstrate that a quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction followed by GC-AP-DBD-MS quantification using the single standard provides acceptable recoveries (80-120%). These results highlight uniform QuEChERS extraction of a range of compounds and the compound-independent response of AP-DBD for Cl, making the combination of the two methods desirable for the rapid quantification of organochlorines. Furthermore, we discuss ionization matrix effects in AP-DBD for chlorine detection and offer strategies to flag matrix-impacted analytes. These results suggest that AP-DBD has the potential to become a unified ion source for both elemental quantification and molecular identification of GC eluents on a single MS platform.

Elemental quantitation of carbon via production of polyatomic anions in gas chromatography-plasma assisted reaction chemical ionization mass spectrometry.

Elemental mass spectrometry offers quantitation and isotopic analysis without the need for compound-specific standards. We have recently introduced plasma assisted reaction chemical ionization (PARCI) as an efficient elemental ionization method for halogens. Here, we report a new ionization chemistry in PARCI for facile quantitation of elemental carbon in gas chromatography eluates. We demonstrate that in-plasma reactions of organic compounds followed by afterglow ionization lead to formation of polyatomic anions (CN-, OCN-, and CO3-), among which CN- offers the best analytical sensitivity with a detection limit of ~25 pg (21 pg/s) carbon on column. Using a mixture of pesticides with wide variations in structures and heteroatom content, we demonstrate that CN- ion response is quantitatively correlated with the carbon concentration over two orders of magnitude (r 2 = 0.985). We show that the novel GC-PARCI-MS method provides recoveries within 80-120% using a single standard for all analytes, highlighting the strength of elemental quantitation. Further, the ability of GC-PARCI-MS to identify 13C-tagged molecules without a priori knowledge of chemical formulas of analytes is demonstrated. Graphical abstract ᅟ.