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Artificial intelligence (AI) is increasingly being used in medicine to enhance the speed and accuracy of disease diagnosis and treatment. AI-based image analysis is expected to play a crucial role in future healthcare facilities and laboratories, offering improved precision and cost-effectiveness. As technology advances, the requirement for specialized software knowledge to utilize AI applications is diminishing. Our study will examine the advantages and challenges of employing AI-based image analysis in the field of immunology and will investigate whether physicians without software expertise can use MS Azure Portal for ANA IIF test classification and image analysis. This is the first study to perform Hep-2 image analysis using MS Azure Portal. We will also assess the potential for AI applications to aid physicians in interpreting ANA IIF results in immunology laboratories. The study was designed in four stages by two specialists. Stage 1: creation of an image library, Stage 2: finding an artificial intelligence application, Stage 3: uploading images and training artificial intelligence, Stage 4: performance analysis of the artificial intelligence application. In the first training, the average pattern identification accuracy for 72 testing images was 81.94%. After the second training, this accuracy increased to 87.5%. Patterns Precision improved from 71.42 to 79.96% after the second training. As a result, the number of correctly identified patterns and their accuracy increased with the second training process. Artificial intelligence-based image analysis shows promising potential. This technology is expected to become essential in healthcare facility laboratories, offering higher accuracy rates and lower costs.
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The coexistence within a subcellular complex of inter-cellular proteins Ro60, responsible for preserving ncRNA quality, and Ro52, involved in intracellular proteolysis, has been a subject of ongoing debate. Employing molecular docking in tandem with experimental methods like Quartz Crystal Microbalance with Dissipation (QCM-D), Proximity Ligation Assay (PLA), and Indirect Immunofluorescence (IIF), we reveal the presence of Ro60 associating with Ro52 within the cytoplasm. This result unveils the formation of a weak transient complex with a Ka ≈ (3.7 ± 0.3) x 106 M-1, where the toroid-shaped Ro60 structure interacts with the Ro52's Fc receptor, aligning horizontally within the PRY-SPRY domains of the Ro52's homodimer. The stability of this complex relies on the interaction between Ro52 chain A and specific Ro60 residues, such as K133, W177, or L185, vital in the Ro60-YRNA bond. These findings bridge the role of Ro60 in YRNA management with Ro52's function in intracellular proteolysis, emphasizing the potential impact of transient complexes on cellular pathways. See also the graphical abstract(Fig. 1).
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Introduction: Anti-rods and rings (anti-RR) antibodies have recently been described as a cytoplasmic pattern in IIF-based screening of autoantibodies on HEp-2 cells and ICAP has named it as AC-23. It is most frequently related to drug-induced antibody generation. This study aimed to investigate the clinical significance of AC-23 positivity and its relevance to the diagnosis and/or follow-up of the associated diseases and/or drug use. Methods: A multicenter retrospective study was conducted among 10 hospitals from six different provinces in Türkiye from January 2017 to December 2021. The laboratory data and clinical information of 600 patients with positive anti-RR antibodies out of 547.558 HEp-2 IIF ANA samples were analyzed. Results: The distribution of AC-23 positive patients by year indicated a steady increase between 2017-2021. Anti-RR prevalence in post-COVID-19 period was significantly higher than that of pre-COVID-19 period (p=0.00). Concomitant ANA positivity was detected in 56.5% of patients, the most common patterns being AC-4 and AC-5 (41.1%). The most frequent pathology among the anti-RR positive patients was an autoimmune disease (19.83%); 28.57% of which had rheumatoid arthritis and 17.65% autoimmune liver disease. Among the 600 patients, 65 (10.83%) were diagnosed as hepatitis C virus (HCV) infection. Available data for 38 of the HCV patients revealed that 71.05% of them had a history of interferon alfa+ribavirin and 28.95% of them had a history of NS3/4/5A/5B polymerase inhibitor or protease inhibitor drug use. Significant increase in the rate of anti-RR positivity was observed in the post-COVID-19 period when compared to pre-COVID-19 period (p:0.00). Discussion: This is the first multicenter study in Türkiye about the clinical association of anti-RR antibodies which may be ignored during routine HEp-2 IIF testing. Pathologies other than HCV should be taken into consideration in terms of the possible role of anti-RR in autoimmune diseases and other pathologies. The preliminary data obtained in this study suggest that anti-RR antibody development might also be associated to COVID-19, supporting the several previous data related to the potential of viruses triggering the formation of autoantibodies. Large-scale prospective studies should elucidate the clinical significance of RR pattern and determine its role in patient diagnosis and follow-up.
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Anticuerpos Antinucleares , COVID-19 , Humanos , Estudios Retrospectivos , Anticuerpos Antinucleares/inmunología , Anticuerpos Antinucleares/sangre , Femenino , Masculino , COVID-19/inmunología , COVID-19/diagnóstico , Persona de Mediana Edad , Técnica del Anticuerpo Fluorescente Indirecta , Anciano , Adulto , SARS-CoV-2/inmunología , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/diagnósticoRESUMEN
Background: The interlobar bronchovascular structures hidden in the incomplete interlobar fissures (IFs) are often inadvertently transected during pulmonary resections, which could inevitably lead to accidental injury and potentially compromise the function of the preserved area. A thorough examination of the anatomical distribution of translobar bronchi, arteries, and veins holds significant clinical importance. Methods: Three-dimensional computed tomography bronchography and angiography (3D-CTBA) data from patients who underwent pulmonary resection between December 2018 and November 2019 were retrospectively analyzed. The translobar bronchi, arteries, and veins were categorized based on their origin and distribution. Surgical results of patients who underwent surgery involving translobar structures were further reviewed. Results: Among the 310 enrolled patients, incomplete IFs (IIFs) were most frequently observed in horizontal fissures (68.7%), followed by right upper oblique fissures (42.3%), left lower oblique fissures (32.6%), left upper oblique fissures (12.9%), and right lower oblique fissures (11.0%). The incidence of bronchovascular structures was significantly higher in IIFs than in complete IFs (CIFs; 85.5% vs. 5.2%, χ2=1,021.1, P<0.001). A total of three subtypes of translobar bronchi, five subtypes of translobar arteries, and 14 subtypes of translobar veins were identified. Primary subtypes of translobar arteries (frequency >5%) included the left A4/5 (18.7%) that branched from A7/8/7+8 and the common trunk of right Asc.A2+A6 (6.1%). Primary subtypes of translobar veins (frequency >5%) included the right V2 draining into inferior pulmonary vein (IPV) (5.8%), the interlobar V3b (58.4%) within horizontal fissures, the right V4/5 draining into V2/3 (26.1%), the left V4/5 draining into IPV (7.4%), the right V6 draining into V2 (38.4%), and the common trunk of left IPV and superior pulmonary vein (SPV; 9.4%). Moreover, 12.0% of translobar arteries and 75.0% of translobar veins were mistransected during anatomical pulmonary resection, resulting in gas-exchanging dysfunction in the preserved territory. Conclusions: Translobar bronchovascular structures exhibited a high incidence and were more commonly present in IIFs. Surgeons should pay increased attention to these structures to prevent accidental injuries during anatomical pulmonary resection.
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Autoantibodies are the hallmark of autoimmunity, and specifically, antinuclear antibodies (ANA) are one of the most relevant antibodies present in systemic autoimmune diseases (AID). In the present study, we evaluate the relationship between ANA and sociodemographic and biobehavioral factors in a population with a low pre-test probability for systemic AID. ANA were determined in serum samples at baseline visit from 2997 participants from the Camargo Cohort using indirect immunofluorescence assay, and two solid phase assays (SPA), addressable laser bead immunoassay, and fluorescence enzyme immunoassay. Sociodemographic and biobehavioral features of the subjects were obtained at baseline visit using a structured questionnaire. The prevalence of ANA positive results was significantly higher when indirect immunofluorescence assay was used as screening method in comparison with SPAs, being higher in females, older subjects, and those with higher C-reactive protein levels. Considering biobehavioral features, the prevalence was higher in those individuals with a sedentary lifestyle, and in ex- and non-alcohol users. Moreover, considering the relevance of the antibody load using ANA Screen, the prevalence of the antibody load also increased with age, especially in females. In conclusion, the prevalence of ANA varies depending on sociodemographic and biobehavioral features of the subjects, which could be relevant specifically in a population with a low pre-test probability for systemic AIDs.
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Epidermal lipids play important roles in skin homeostasis and diseases. Psoriasis is an inflammatory disease characterized by keratinocyte hyperproliferation and Th17 immune responses. We previously reported that ethanolamine-type lysoplasmalogen (P-LPE), preferentially produced by group IIF secreted PLA2 (sPLA2-IIF/PLA2G2F) that is expressed in the suprabasal epidermis, promotes epidermal hyperplasia in psoriatic inflammation. Herein, we show that forcible degradation of epidermal P-LPE by topical application of recombinant lysophospholipase D (LyPls-PLD) from Thermocrispum, a lysoplasmalogen-specific hydrolase, attenuated epidermal hyperplasia and inflammation in imiquimod-induced and K5.Stat3C-transgenic mouse psoriasis models. In humans, P-LPE levels were elevated in the tape-stripped stratum corneum of patients with psoriasis. Moreover, in primary cultured human epidermal keratinocytes, aberrant cell proliferation and activation by psoriatic cytokines were sPLA2-IIF/P-LPE-dependent and were suppressed by the addition of LyPls-PLD with a decrease in P-LPE. These findings confirm that the sPLA2-IIF/P-LPE axis in the epidermis indeed regulates psoriasis, that P-LPE is a lipid biomarker that predicts the severity of psoriasis, and that pharmacological removal of this bioactive lipid is useful to prevent the disease. Thus, our study may lead to the development of drug discovery and diagnostic techniques based on this pathway.
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Fosfolipasas A2 Secretoras , Psoriasis , Ratones , Animales , Humanos , Hiperplasia/metabolismo , Epidermis/metabolismo , Epidermis/patología , Queratinocitos/metabolismo , Inflamación/metabolismo , Psoriasis/metabolismo , Ratones Transgénicos , Fosfolipasas A2 Secretoras/metabolismo , LípidosRESUMEN
Antinuclear antibodies (ANA) are the most widely used immunological test for the diagnosis of autoimmune diseases. Despite the recommendations of experts, there is some variability in performing and interpreting this test in routine practice. In this context, the Spanish Group on Autoimmune Diseases (GEAI) of the Spanish Society of Immunology (SEI) conducted a national survey of 50 autoimmunity laboratories. Here we report the survey results on ANA testing, detection of related antigens, and our recommendations. The survey showed that most of the participating laboratories use a similar approach for most key practices: 84% perform ANA by indirect immunofluorescence (IIF) on HEp-2 cells as the screening methodology while the other laboratories use IIF to confirm positive screens; 90% report ANA test results as either negative or positive with titer and pattern; 86% indicated that the ANA pattern conditioned follow-up testing for specific antigen-related antibodies; and 70% confirm positive anti-dsDNA. However, testing practices were highly heterogeneous for certain items, such as sera dilutions and the minimum time period for repeating ANA and related antigen determinations. Overall, this survey shows that most autoimmune laboratories in Spain use a similar approach but that further standardization of testing and reporting protocols is needed.
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Anticuerpos Antinucleares , Enfermedades Autoinmunes , Humanos , Laboratorios , Pruebas Inmunológicas , Técnica del Anticuerpo Fluorescente Indirecta/métodosRESUMEN
Metacaspases are part of an evolutionarily broad family of multifunctional cysteine proteases, involved in disease and normal development. As the structure-function relationship of metacaspases remains poorly understood, we solved the X-ray crystal structure of an Arabidopsis thaliana type II metacaspase (AtMCA-IIf) belonging to a particular subgroup not requiring calcium ions for activation. To study metacaspase activity in plants, we developed an in vitro chemical screen to identify small molecule metacaspase inhibitors and found several hits with a minimal thioxodihydropyrimidine-dione structure, of which some are specific AtMCA-IIf inhibitors. We provide mechanistic insight into the basis of inhibition by the TDP-containing compounds through molecular docking onto the AtMCA-IIf crystal structure. Finally, a TDP-containing compound (TDP6) effectively hampered lateral root emergence in vivo, probably through inhibition of metacaspases specifically expressed in the endodermal cells overlying developing lateral root primordia. In the future, the small compound inhibitors and crystal structure of AtMCA-IIf can be used to study metacaspases in other species, such as important human pathogens, including those causing neglected diseases.
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Arabidopsis , Caspasas , Humanos , Caspasas/química , Simulación del Acoplamiento Molecular , Apoptosis , Proteínas de Unión al ADNRESUMEN
The antinuclear antibody (ANA) test has high sensitivity in diagnosing and classifying systemic lupus erythematosus (SLE). OBJECTIVES: To describe the immunological pattern of SLE patients through investigating specific antinuclear autoantibodies by enzyme dot immunoassay and studying their frequency in both positive and negative ANA indirect immunofluorescence assay (IIF) cases. METHODS: In a cross-sectional study, blood samples from 393 newly diagnosed SLE patients were analyzed using (IIF) on HEp-2 cells and ANA dot immunoassay by automated enzyme immunoassay (EIA) to detect 19 antibodies. RESULTS: Ninety-one percent of the patients are females; their mean age was 37 ± 12.28. Antinuclear antibody (ANA) was detected by IIF in 82.4% of cases, with 181 (46.1%) speckled and 167 (42.4%) homogeneous ANA patterns. The majority of patients (96%) demonstrated autoantibodies via EIA. Among the ANA-IIF-negative patients, 97.2% demonstrated autoantibodies. There was a significant difference in the frequency of certain autoantibodies between SLE patients with negative and positive ANA-IIF (1.44 0.73, 3.12 2.09, p = 0.00) respectively. CONCLUSION: The results of analyzing 19 autoantibodies with the ANA staining pattern increased the significance of analyzing the immune profile even if IIF is negative when clinical symptoms strongly suggest SLE diagnosis. Certain autoantibodies may evade staining by the IFA approach while they are present in the patient's serum, and they may not be detected by the ANA EIA profile if it does not contain that antigenic substrate. Key Points ⢠Indirect immunofluorescence on Hep-2 is the conventional method for ANA detection and is regarded as the "gold standard" for testing in clinical practice for SLE. ⢠In our study, ANA profile dot enzyme immunoassay (EIA)-based test was performed to evaluate 19 autoantibodies in SLE patients either positive or negative for ANA-IIF. ⢠The presence of anti-dsDNA with ANA-IIF-negative serum in 32.4% of SLE patients provides evidence that not all anti-dsDNA antibodies are identified on standard HEp-2 substrates. ⢠certain autoantibodies can evade staining by the ANA-IIF method despite being present in the SLE patient's blood; this supports the ANA profile enzyme dot immunoassay as a more sensitive test.
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Anticuerpos Antinucleares , Lupus Eritematoso Sistémico , Femenino , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , Masculino , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Estudios Transversales , AutoanticuerposRESUMEN
OBJECTIVES: Autoantibodies and, specifically antinuclear antibodies (ANA), are the hallmark of systemic autoimmune diseases (AID). In the last decades, there has been great technical development to detect these autoantibodies along with an increased request for this test by clinicians, while the overall pre-test probability has decreased. In this study, we compare the diagnostic performance of three different methods for ANA screening (indirect immunofluorescence [IIF], addressable laser bead immunoassay [ALBIA], and fluorescence enzyme immunoassay [FEIA]). METHODS: Serum samples at baseline visit from 2,997 participants from the Camargo Cohort, a population with an overall low pre-test probability for systemic AID, were analyzed with the three methods. Participants have a minimum follow-up of 10 years and the development of autoimmune diseases was collected from clinical records. RESULTS: The highest frequency of positive ANA was observed by IIF assay. However, ALBIA showed high sensitivity for AID. Likewise, solid phase assays (SPA) presented higher specificity than IIF for AID. ANA prevalence with any method was significantly higher in females and overall increased with age. Triple positivity for ANA was significantly related to the presence of anti-dsDNA-SSA/Ro60, Ro52, SSB/La, RNP, Scl-70, and centromere-specificities. No association was found for anti-Sm - RNP68, or ribosomal P - specificities. Noteworthy, triple positivity for ANA screening was associated with diagnosis of systemic AID both at baseline visit and follow-up. CONCLUSIONS: ANA detection by IIF may be better when the pre-test probability is high, whereas SPA techniques are more useful in populations with an overall low pre-test probability for systemic AID.
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Anticuerpos Antinucleares , Enfermedades Autoinmunes , Femenino , Humanos , Autoanticuerpos , Enfermedades Autoinmunes/diagnóstico , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Inmunoensayo/métodosRESUMEN
OBJECTIVES: Antinuclear antibodies (ANAs) are associated with several autoimmune diseases. Indirect immunofluorescence (IIF) on human epithelial type 2 (HEp-2) cells is the golden standard for ANA detection in the clinic. In case of a positive HEp-2 IIF test result, follow-up tests are done to determine autoantibody specificity. For a fraction of the HEp-2 IIF-positive samples, the nature of the autoantigens remains uncharacterized. Our objective was to characterize autoantigens in such samples. METHODS: To characterize autoantigens in an unbiased way, we combined protein immunoprecipitation with liquid chromatography (LC) tandem mass spectrometry (MS/MS) sequencing. RESULTS: Using such approach we detected the Ki antigen, also referred to as PA28γ, in the immunoprecipitate of serum samples of three individuals with an autoimmune disease. The HEp-2 nuclear speckled IIF fluorescent signal of all three serum samples was abolished after pre-absorption of the serum with recombinant Ki antigen, confirming that autoantibodies against Ki underlie the HEp-2 IIF signal. CONCLUSIONS: Our data suggest that anti-Ki autoantibodies can underlie a nuclear speckled HEp-2 IIF pattern.
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Autoanticuerpos , Enfermedades Autoinmunes , Humanos , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Espectrometría de Masas en Tándem , Autoantígenos , Anticuerpos Antinucleares , Enfermedades Autoinmunes/diagnósticoRESUMEN
Background: For the management of connective tissue disorders (CTDs), antinuclear antibody (ANA) testing is essential, both from diagnostic and prognostic points of view. Usually, patterns obtained by ANA-IIF testing correlates to specific autoantibodies as obtained from the test for ENA (by LIA/ELISA, etc.). But to apply these data from western studies, we may need validation in the local population like our subjects in sub-Himalayan (Garhwal region) area where CTDs are common. Also, suppose ANA-IFA pattern's correlation is reliably known in our population, it can minimize the cost of managing CTDs by limiting ENA testing, which is 10 times costlier than ANA-IIF. Hence, this study was undertaken to know the specific autoantibody targets (ENA by LIA) against ANA-IIF patterns in our local population. Materials and Methods: In this retrospective cross-sectional work, serum samples of CTDs were tested for ANA by IIF (Euroimmune AG) and ENA by LIA (Euroline ANA-3G) continuously for 36 months. The manufacturer's kit insert was followed, and results were analyzed applying appropriate statistical methods. Results: Major ANA-IIF patterns were found to be associated with specific autoantibodies, for example, Nuclear homogenous with dsDNA, nucleosomes, histones; speckled pattern with nRNP/Sm, Sm, SSA/Ro-52, SSB; nucleolar pattern with Scl-70, Pm-Scl 100 and centromere pattern with CENP-B. Anticytoplasmic (ACA) are found to be linked with some ANA negative (by IIF) samples, emphasizing the need for careful observation for ACA especially where ANA is not found. Conclusions: In most subjects, specific ENA targets correlated well with ANA-IIF patterns, implying effective cost minimization in CTD management. Similar future prospective studies (with clinical data) can provide a database and reference for our population.
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Anticuerpos Antinucleares , Enfermedades del Tejido Conjuntivo , Humanos , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Anticuerpos Antinucleares/análisis , Estudios Transversales , Estudios Retrospectivos , Estudios Prospectivos , Estudios de Factibilidad , Autoanticuerpos , Enfermedades del Tejido Conjuntivo/diagnóstico , IndiaRESUMEN
Mitochondria play a major role in energy metabolism, particularly in cell respiration, cellular metabolism, and signal transduction, and are also involved in other processes, such as cell signaling, cell cycle control, cell growth, differentiation and apoptosis. Programmed cell death is associated with the production of reactive oxygen species (ROS) and a concomitant decrease in antioxidant capacity, which, in turn, determines the aging of living organisms and organs and thus also seeds. During the aging process, cell redox homeostasis is disrupted, and these changes decrease the viability of stored seeds. Mitochondrial peroxiredoxin-IIF (PRXIIF), a thiol peroxidase, has a significant role in protecting the cell and sensing oxidative stress that occurs during the disturbance of redox homeostasis. Thioredoxins (TRXs), which function as redox transmitters and switch protein function in mitochondria, can regulate respiratory metabolism. TRXs serve as electron donors to PRXIIF, as shown in Arabidopsis. In contrast, sulfiredoxin (SRX) can regenerate mitochondrial PRXIIF once hyperoxidized to sulfinic acid. To protect against oxidative stress, another type of thiol peroxidases, glutathione peroxidase-like protein (GPXL), is important and receives electrons from the TRX system. They remove peroxides produced in the mitochondrial matrix. However, the TRX/PRX and TRX/GPXL systems are not well understood in mitochondria. Knowledge of both systems is important because these systems play an important role in stress sensing, response and acclimation, including redox imbalance and generation of ROS and reactive nitrogen species (RNS). The TRX/PRX and TRX/GPXL systems are important for maintaining cellular ROS homeostasis and maintaining redox homeostasis under stress conditions. This minireview focuses on the functions of PRXIIF discovered in plant cells approximately 20 years ago and addresses the question of how PRXIIF affects seed viability maintenance and aging. Increasing evidence suggests that the mitochondrial PRXIIF plays a major role in metabolic processes in seeds, which was not previously known.
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Autoantibodies are a hallmark of autoimmunity and, specifically, antinuclear antibodies (ANAs) are the most relevant autoantibodies present in systemic autoimmune rheumatic diseases (SARDs). Over the years, different methods from LE cell to HEp-2 indirect immunofluorescence (IIF), solid-phase assays (SPAs), and finally multianalyte technologies have been developed to study ANA-associated SARDs. All of them provide complementary information that is important to provide the most clinically valuable information. The identification of new biomarkers together with multianalyte platforms will help close the so-called "seronegative gap" and to correctly classify and diagnose patients with SARDs. Finally, artificial intelligence and machine learning is an area still to be exploited but in a next future will help to extract patterns within patient data, and exploit these patterns to predict patient outcomes for improved clinical management.
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BACKGROUND: The Bosniak classification is a CT classification which stratifies renal cysts based on imaging appearances and therefore associated risk of malignancy. Bosniak IIf cysts are renal which have complex features and therefore require surveillance. AIMS: The aim of this study is to assess the economic and workload burden of diagnosing and following up Bosniak IIf cysts on the urology service in a tertiary hospital in the West of Ireland. METHODS: All patients with a diagnosis of Bosniak IIf renal cysts attending our urology service between 1st of January 2012 and 31st December 2020 were analysed. The following data were collected: number and modality of follow up scans, number of MDT discussions, number and type of outpatient appointments, surgical intervention, and length of follow up. Financial data were provided by the hospital finance department. RESULTS: One hundred and sixty-two patients were included. Total cost of follow up was 164,056, costing 1,012.7 per patient. Cost of outpatient visits was 77,850. Follow-up length ranged from 1 to 109 months, median follow up time 17.5 months. Overall cost of imaging was 74,518. There were a total of 80 MDT discussions at an overall cost of 11,688. CONCLUSIONS: This study demonstrates that surveillance of patients with Bosniak IIf renal cysts represents a significant burden upon both radiology and urology services. Surveillance for these patients could be streamlined in the future through a number of initiatives such as virtual OPDs and dedicated MDTs.
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Quistes , Enfermedades Renales Quísticas , Neoplasias Renales , Humanos , Centros de Atención Terciaria , Estrés Financiero , Carga de Trabajo , Enfermedades Renales Quísticas/diagnóstico por imagen , Enfermedades Renales Quísticas/epidemiología , Neoplasias Renales/patología , Estudios RetrospectivosRESUMEN
Anti-neutrophil cytoplasmic antibodies (ANCAs) are autoantibodies that recognize neutrophil cytoplasmic antigens. The major ANCA antigens are myeloperoxidase and proteinase 3. Necrotizing small vessel vasculitis accompanied by ANCA production is called ANCA-associated vasculitis (AAV). In addition to AAV, ANCA is sometimes produced in patients with connective tissue diseases, such as systemic lupus erythematosus, and inflammatory bowel diseases. Indirect immunofluorescence (IIF) and enzyme immunoassay (EIA) have been used to detect ANCAs. Recently, the accuracy of EIA has improved and it has become the gold standard for ANCA detection. However, IIF does not lose its role in ANCA detection because EIA cannot detect ANCAs that recognize antigens other than those coated on the plate. For IIF, neutrophil substrates prepared with two different fixations, namely, ethanol fixation and formalin fixation, are used. There is a recommended protocol for ethanol fixation but not for formalin fixation. This study prepared neutrophil substrates according to the recommended protocol for ethanol fixation and protocols in the literature and original protocols for formalin fixation and then examined ANCA specificity and how storage period would influence the number of cells, antigen distribution, and antigenicity of the substrates. As a result, the number of cells and antigen distribution did not change after storage for up to 2 months regardless of fixation protocols, whereas a time-dependent decline in ANCA antigenicity and a fixation protocol-dependent difference in ANCA specificity were observed. How neutrophils are fixed on the glass slide needs to be checked upon evaluation of ANCAs by IIF.
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Anticuerpos Anticitoplasma de Neutrófilos/análisis , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Neutrófilos , Fijación del Tejido/métodos , Etanol/farmacología , Fijadores/farmacología , Formaldehído/farmacología , Humanos , Sensibilidad y Especificidad , Manejo de Especímenes/métodosRESUMEN
Feline morbillivirus (FeMV) was isolated for the first time in 2012 with an association with chronic kidney disease (CKD) suggested. This study aimed at investigating in cats from southern Italy FeMV prevalence and risk factors for exposure to FeMV, including the relationship with CKD; sequencing amplicons and analyzing phylogeny of PCR positive samples. Blood serum, K3EDTA blood and urine samples from 223 cats were investigated. Ten carcasses were also evaluated. FeMV RNA was detected in 2.4% (5/211) blood and 16.1% (36/223) urine samples. One carcass tested positive by qPCRFeMV from kidney, urinary bladder, and submandibular lymph nodes. Antibodies against FeMV were detected in 14.5% (28/193) cats. We followed up 27 cats (13 FeMV positive cats) and documented in some cases urine shedding after up to 360 days. Older and foundling cats and cats living in rescue catteries, were more frequently infected with FeMV. A significant correlation between FeMV and higher serum creatinine values or low urine specific gravity was found. FeMV positivity was significantly associated with retroviral infection, and the presence of some clinical signs apart from CKD clinicopathological markers. Our study highlights the possibility of a link between FeMV exposure and CKD and a general impairment of feline health.