ABSTRACT
OBJECTIVES: The aims of this study were to investigate the prevalence of dose reduction in patients with SLE treated with belimumab (BEL) in Spain, analyze treatment modalities, and determine impact on control of disease activity. METHODS: Retrospective longitudinal and multicentre study of SLE patients treated with BEL. Data on disease activity, treatments and outcomes were recorded before and after reduction (6-12 months), and they were compared. RESULTS: A total of 324 patients were included. The dose was reduced in 29 patients (8.9%). The dosing interval was increased in 9 patients receiving subcutaneous BEL and in 6 patients receiving intravenous BEL. The dose per administration was reduced in 16 patients.Pre-reduction status was remission (2021 DORIS) in 15/26 patients (57.7%) and LLDAS in 23/26 patients (88.5%). After reduction, 2/24 patients (8.3%) and 3/22 patients (13.6%) lost remission at 6 months and 12 months, respectively (not statistically significant [NS]). As for LLDAS, 2/23 patients (8.7%) and 2/21 patients (9.5%) lost their status at 6 and 12 months, respectively (NS). Significantly fewer patients were taking glucocorticoids (GCs) at their 12-month visit, although the median dose of GCs was higher at the 12-month visit (5 [0.62-8.75] vs 2.5 [0-5] at baseline). CONCLUSION: Doses of BEL can be reduced with no relevant changes in disease activity-at least in the short term-in a significant percentage of patients, and most maintain the reduced dose. However, increased clinical or serologic activity may be observed in some patients. Consequently, tighter post-reduction follow-up is advisable.
ABSTRACT
BACKGROUND: Persistent periapical lesions (PPL) are the result of pulpar necrosis induced by bacterial infection resulting in bone degradation and culminating with the loss of dental piece. Pathological changes in the peripapice are associated with the presence of free radicals. The transcription factor Nrf2 is the main regulator of the endogenous antioxidant response against oxidative stress and has been implicated in the regulation of osteoclastogenesis.The aim is to determine the oxidative condition in samples from patients with Persistent Periapical Injuries as a detonating factor of tissue damage. MATERIAL AND METHODS: An observational, descriptive, cross-sectional study was carried out in samples with PPL (cases) and samples by removal of third molars (controls) obtained in the clinic of the specialty in endodontics, University of Guadalajara. Samples were submitted to histological staining with Hematoxylin-Eosin, lipoperoxide analysis, Superoxide Dismutase (SOD), Glutathione-Peroxidase (GPx) and Catalase (CAT) activities were determined by immunoenzymatic assays and NrF2 by Western Blot analysis. RESULTS: Samples from PPL patients histologically showed an increased presence of lymphocytes, plasma cells, and eosinophils, as well as a decrease in extracellular matrix proteins and fibroblast cells. There was a rise in lipid peroxidation, GPx and SOD activities, but an important decline (36%) in Catalase activity was observed (p<0.005); finally, NrF2-protein was diminished at 10.41%. All comparisons were between cases vs controls. CONCLUSIONS: The alterations in antioxidants endogenous NrF2-controlled are related to osseous destruction in patients with PPL.
Subject(s)
Antioxidants , NF-E2-Related Factor 2 , Catalase/metabolism , NF-E2-Related Factor 2/metabolism , Cross-Sectional Studies , Antioxidants/metabolism , Superoxide Dismutase/metabolism , Glutathione Peroxidase/metabolismABSTRACT
Hazara nairovirus (HAZV) is an enveloped trisegmented negative-strand RNA virus classified within the Nairoviridae family of the Bunyavirales order and a member of the same subtype as Crimean-Congo hemorrhagic fever virus, responsible for fatal human disease. Nairoviral subversion of cellular trafficking pathways to permit viral entry, gene expression, assembly, and egress is poorly understood. Here, we generated a recombinant HAZV expressing enhanced green fluorescent protein and used live-cell fluorescent imaging to screen an siRNA library targeting genes involved in cellular trafficking networks, the first such screen for a nairovirus. The screen revealed prominent roles for subunits of the coat protein 1 (COPI)-vesicle coatomer, which regulates retrograde trafficking of cargo between the Golgi apparatus and the endoplasmic reticulum, as well as intra-Golgi transport. We show the requirement of COPI-coatomer subunits impacted at least two stages of the HAZV replication cycle: an early stage prior to and including gene expression and also a later stage during assembly and egress of infectious virus, with COPI-knockdown reducing titers by approximately 1,000-fold. Treatment of HAZV-infected cells with brefeldin A (BFA), an inhibitor of Arf1 activation required for COPI coatomer formation, revealed that this late COPI-dependent stage was Arf1 dependent, consistent with the established role of Arf1 in COPI vesicle formation. In contrast, the early COPI-dependent stage was Arf1 independent, with neither BFA treatment nor siRNA-mediated ARF1 knockdown affecting HAZV gene expression. HAZV exploitation of COPI components in a noncanonical Arf1-independent process suggests that COPI coatomer components may perform roles unrelated to vesicle formation, adding further complexity to our understanding of cargo-mediated transport.IMPORTANCE Nairoviruses are tick-borne enveloped RNA viruses that include several pathogens responsible for fatal disease in humans and animals. Here, we analyzed host genes involved in trafficking networks to examine their involvement in nairovirus replication. We revealed important roles for genes that express multiple components of the COPI complex, which regulates transport of Golgi apparatus-resident cargos. COPI components influenced at least two stages of the nairovirus replication cycle: an early stage prior to and including gene expression and also a later stage during assembly of infectious virus, with COPI knockdown reducing titers by approximately 1,000-fold. Importantly, while the late stage was Arf1 dependent, as expected for canonical COPI vesicle formation, the early stage was found to be Arf1 independent, suggestive of a previously unreported function of COPI unrelated to vesicle formation. Collectively, these data improve our understanding of nairovirus host-pathogen interactions and suggest a new Arf1-independent role for components of the COPI coatomer complex.
Subject(s)
ADP-Ribosylation Factor 1/genetics , ADP-Ribosylation Factor 1/metabolism , Coat Protein Complex I/genetics , Coat Protein Complex I/metabolism , Nairovirus/genetics , Nairovirus/metabolism , Virus Replication/physiology , Animals , Brefeldin A , Endoplasmic Reticulum/metabolism , Gene Expression Regulation, Viral , Gene Knockdown Techniques , Golgi Apparatus/metabolism , Host-Pathogen Interactions/genetics , Host-Pathogen Interactions/physiology , Nairovirus/pathogenicity , Protein Transport , RNA, Small Interfering , Virus Replication/geneticsABSTRACT
The Nairoviridae family within the Bunyavirales order comprise tick-borne segmented negative-sense RNA viruses that cause serious disease in a broad range of mammals, yet cause a latent and lifelong infection in tick hosts. An important member of this family is Crimean-Congo haemorrhagic fever virus (CCHFV), which is responsible for serious human disease that results in case fatality rates of up to 30â%, and which exhibits the most geographically broad distribution of any tick-borne virus. Here, we explored differences in the cellular response of both mammalian and tick cells to nairovirus infection using Hazara virus (HAZV), which is a close relative of CCHFV within the CCHFV serogroup. We show that HAZV infection of human-derived SW13 cells led to induction of apoptosis, evidenced by activation of cellular caspases 3, 7 and 9. This was followed by cleavage of the classical apoptosis marker poly ADP-ribose polymerase, as well as cellular genome fragmentation. In addition, we show that the HAZV nucleocapsid (N) protein was abundantly cleaved by caspase 3 in these mammalian cells at a conserved DQVD motif exposed at the tip of its arm domain, and that cleaved HAZV-N was subsequently packaged into nascent virions. However, in stark contrast, we show for the first time that nairovirus infection of cells of the tick vector failed to induce apoptosis, as evidenced by undetectable levels of cleaved caspases and lack of cleaved HAZV-N. Our findings reveal that nairoviruses elicit diametrically opposed cellular responses in mammalian and tick cells, which may influence the infection outcome in the respective hosts.
Subject(s)
Apoptosis , Bunyaviridae Infections/physiopathology , Nairovirus/metabolism , Nucleocapsid Proteins/metabolism , Ticks/virology , Amino Acid Motifs , Animals , Bunyaviridae Infections/enzymology , Bunyaviridae Infections/genetics , Bunyaviridae Infections/virology , Caspase 3/genetics , Caspase 3/metabolism , Caspase 7/genetics , Caspase 7/metabolism , Cell Line , Host-Pathogen Interactions , Humans , Nairovirus/chemistry , Nairovirus/genetics , Nucleocapsid Proteins/chemistry , Nucleocapsid Proteins/genetics , Protein Processing, Post-TranslationalABSTRACT
Vinca (Catharantus roseus (L.) G. Don) is a common ornamental landscape plant. From July to September 2012, blighted and wilted vinca plants were found in retail stores, commercial nurseries, and urban landscape areas of Culiacan, Sinaloa, in northwestern Mexico. In several commercial nurseries and a retail store, incidence of the unknown disease on vinca plants ranged from 20 to 50%, resulting in significant economic losses. Symptoms of the disease started with a foliar blight, and if warm and wet conditions were present, the disease progressed, causing plant wilting and death. Surface-sterilized (0.5% NaOCl 1 min) diseased plant tissue was plated on V8 agar medium, and after 72 h of incubation at 25°C, white colonies of coenocytic mycelium were developed from the plated tissues. Isolates produced cottony colonies on V8 agar medium, grew well between 7 and 30°C (optimum of 25°C), and produced spherical, intercalary, and terminal chlamydospores (17 to 30 µm) and non caducous, papillate, spherical to ovoid sporangia of 30 to 39 × 21 to 31 µm. Based on these morphological characteristics, Phytophthora isolates were identified as Phytophthora nicotianae Breda de Haan (1,3). The identity of two representative isolates OV4 and OV11 was confirmed by sequence analysis of the rDNA internal transcribed spacers (ITS; GenBank Accession Nos. KC248202 and KC248201), and of the ß-tubulin (ß-tub; KC248404 and KC248403) and translation elongation factor 1-α (EF1-α; KC248206 and KC248205) genes. Comparative sequence analysis against the NCBI nucleotide database showed a high degree of identity with reference sequences of P. nicotianae (ITS, 99%; ß-tub, 99%; EF1-α, 100%) (2). A pathogenicity test with a representative isolate of P. nicotianae was performed on 10-week-old healthy vinca seedlings (n = 10). An aliquot of 10 ml of a zoosporic suspension (104 zoospores/ml) was sprayed onto the seedlings' leaves. An equal number of non-inoculated control seedlings were sprayed with sterile distilled water. Seedlings were maintained in a moist chamber at 25°C with 80 to 90% relative humidity and watered as needed with sterile water. Inoculated plants showed initial symptoms of foliar blight after 4 days, whereas control plants remained healthy. Ten days after inoculation, inoculated plants showed severe wilting. P. nicotianae was reisolated only from inoculated plants, thus fulfilling Koch's postulates. To our knowledge, this is the first report of P. nicotianae attacking annual vinca in northwestern Mexico. References: (1) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul, MN, 1996. (2) L. P. Kroon et al. Fungal Genet Biol. 41:766, 2004. (3) F. N. Martin et al. Plant Dis. 96:1080, 2013.