Association Between Causative Pathogen and Occurrence of Infection-Related Glomerulonephritis in Infective Endocarditis.

Among patients with pathologically proven infective endocarditis, the association of pathogen with occurrence of infection-related glomerulonephritis (IRGN) was examined in 48 case patients with IRGN and 192 propensity score-matched controls. Bartonella was very strongly associated with IRGN (odds ratio, 38.2 [95% confidence interval, 6.7-718.8]; P < .001); other microorganisms were not.

High frequency of multidrug-resistant Escherichia coli from cattle in the Cerrado and Pantanal biomes of Brazil.

The indiscriminate use of antimicrobials has led to the emergence of resistant bacteria, especially pathogenic strains of Escherichia coli, which are associated with diseases in animals and humans. The aim of the present study was to characterize E. coli isolates in calves with regards to the presence of virulence genes and investigate the resistance of the isolates to different antimicrobials. Between 2021 and 2023, 456 fecal samples were collected from calves in the Pantanal and Cerrado biomes of the state of Mato Grosso do Sul, Brazil. All samples were subjected to microbiological analysis and disc diffusion antibiogram testing. The polymerase chain reaction method was used to detect virulence genes. Bacterial growth was found in 451 of the 456 samples and biochemically identified as Escherichia coli. All 451 isolates (100 %) exhibited some phenotypic resistance to antimicrobials and 67.62 % exhibited multidrug resistance. The frequency of multidrug-resistant isolates in the Cerrado biome was significantly higher than that in the Pantanal biome (p = 0.0001). In the Cerrado, the most common pathotype was Shiga toxin-producing Escherichia coli (STEC) (28 %), followed by toxigenic Escherichia coli (ETEC) (11 %), enterohemorrhagic Escherichia coli (EHEC) (8 %) and enteropathogenic Escherichia coli (EPEC) (2 %). In most cases, the concomitant occurrence of pathotypes was more common, the most frequent of which were ETEC + STEC (33 %), ETEC + EHEC (15 %) and ETEC + EPEC (3 %). The STEC pathotype (30 %) was also found more frequently in the Pantanal, followed by EHEC (12 %), ETEC (9 %) and EPEC (6 %). The STEC pathotype had a significantly higher frequency of multidrug resistance (p = 0.0486) compared to the other pathotypes identified. The frequency of resistance was lower in strains from the Pantanal biome compared to those from the Cerrado biome. Although some factors are discussed in this paper, it is necessary to clarify the reasons for this difference and the possible impacts of these findings on both animal and human health in the region.

Podocyte density is reduced in kidney allografts with high-risk APOL1 genotypes at transplantation.

Variants in apolipoprotein L1 (APOL1) gene are associated with nondiabetic kidney diseases in black subjects and reduced kidney transplant graft survival. Living and deceased black kidney donors (n = 107) were genotyped for APOL1 variants. To determine whether allografts from high-risk APOL1 donors have reduced podocyte densities contributing to allograft failure, we morphometrically estimated podocyte number, glomerular volume, and podocyte density. We compared allograft loss and eGFR trajectories stratified by APOL1 high-risk and low-risk genotypes. Demographic characteristics were similar in high-risk (n = 16) and low-risk (n = 91) donors. Podocyte density was significantly lower in high-risk than low-risk donors (108 ± 26 vs 127 ± 40 podocytes/106 um3 , P = .03). Kaplan-Meier graft survival (high-risk 61% vs. low-risk 91%, p-value = 0.049) and multivariable Cox models (hazard ratio = 2.6; 95% CI, 0.9-7.8) revealed higher graft loss in recipients of APOL1 high-risk allografts over 48 months. More rapid eGFR decline was seen in recipients of high-risk APOL1 allografts (P < .001). At 60 months, eGFR was 27 vs. 51 mL/min/1.73 min2 in recipients of APOL1 high-risk vs low-risk kidney allografts, respectively. Kidneys from high-risk APOL1 donors had worse outcomes versus low-risk APOL1 genotypes. Lower podocyte density in kidneys from high-risk APOL1 donors may increase susceptibility to CKD from subsequent stresses in both the recipients and donors.

IgA Vasculitis in Adults: a Rare yet Challenging Disease.

PURPOSE OF REVIEW: IgA vasculitis (IgAV) is a rare and poorly understood systemic vasculitis in adults. Its diagnosis and treatment remain a challenge. Herein, we review the clinical manifestations, diagnosis, management, and prognosis of IgAV in adults. RECENT FINDINGS: The clinical course of IgAV in adults appears to be different from pediatric IgAV, especially due to its higher risk of evolving into end-stage renal disease. Rising awareness and interest in adult-onset IgA vasculitis has resulted in recent increasing number of publications on different treatment experiences. However, there is still controversy over the role of glucocorticoid (GC) and different immunosuppressive therapies such as cyclophosphamide, rituximab, and mychophenolate mofetil for more severe IgAV. Data regarding potential benefits of targeting the mucosal immune system, toll-like receptors, complements, and tyrosine kinase inhibitors in the treatment of IgA nephropathy are emerging. High quality evidence or guidelines in the treatment of severe IgAV are lacking and there is still a great need for controlled trials.

Motility and cell shape roles in the rheology of growing bacteria cultures.

Cell shape, size and self-motility appear as determinant intrinsic cell factors in the rheological behavior of living bacterial cultures during the growth process. In this work three different species were considered due to their differences on these intrinsic characteristics: two different strains of Staphylococcus aureus - strain COL and its isogenic cell wall autolysis mutant, RUSAL9 - both non-motile and Escherichia coli and Bacillus subtilis - both presenting intrinsic motility. In situ real-time rheology, was used to characterize the activity of growing bacteria, under steady-shear conditions, in particular the viscosity growth curve was measured, for a constant shear flow rate, presenting for all studied cultures, different and rich flow curves. These complex rheological behaviors are a consequence of two coupled effects: the cell density continuous increase and its changing interacting properties, where cell size and shape and intrinsic motility are major players.

C3 glomerulonephritis and dense deposit disease share a similar disease course in a large United States cohort of patients with C3 glomerulopathy.

C3 glomerulonephritis (C3GN) and dense deposit disease comprise the two classes of C3 glomerulopathy. Studies from Europe and Asia have aided our understanding of this recently defined disorder, but whether these data apply to a diverse United States patient population remains unclear. We, therefore, reviewed clinical and histopathological data, including generation of a C3 Glomerulopathy Histologic Index to score biopsy activity and chronicity, to determine predictors of progression to end-stage renal disease (ESRD) and advanced chronic kidney disease (CKD) in 111 patients (approximately 35% non-white) with C3 glomerulopathy: 87 with C3GN and 24 with dense deposit disease. Complement-associated gene variants and autoantibodies were detected in 24% and 35% of screened patients, respectively. Our C3 Glomerulopathy Histologic Index denoted higher activity in patients with C3GN and higher chronicity in patients with dense deposit disease. Over an average of 72 months of follow-up, remission occurred in 38% of patients with C3GN and 25% of patients with dense deposit disease. Progression to late-stage CKD and ESRD was common, with no differences between C3GN (39%) and dense deposit disease (42%). In multivariable models, the strongest predictors for progression were estimated glomerular filtration rate at diagnosis (clinical variables model) and tubular atrophy/interstitial fibrosis (histopathology variables model). Using our C3 Glomerulopathy Histologic Index, both total activity and total chronicity scores emerged as the strongest predictors of progression. Thus, in a large, diverse American cohort of patients with C3 glomerulopathy, there is a high rate of progression to CKD and ESRD with no differences between C3GN and dense deposit disease.

Assessment of ecotoxicological effects of ciprofloxacin in Daphnia magna: life-history traits, biochemical and genotoxic effects.

Antibiotics (e.g. ciprofloxacin) have been detected in surface water and groundwater for several decades. In order to understand the potential impact of the continuous exposure of aquatic organisms to ciprofloxacin, a chronic assay was carried out with Daphnia magna. This approach allowed evaluation of the effects of ciprofloxacin on life-history and sub-individual parameters (antioxidant status and metabolic response: activities of catalase and glutathione S-transferases - GSTs; peroxidative damage; thiobarbituric acid reactive substances and genotoxic effects (genetic damage index, measured by the comet assay). Life-history parameters of D. magna showed no significant effects after ciprofloxacin exposure. Concerning oxidative stress and metabolism parameters, no significant alterations were reported for catalase and GSTs activities. However, a dual response was observed, with a significant decrease in lipid peroxidation levels at low ciprofloxacin concentrations (<0.013 mg/L), while a significant increase was verified at high ciprofloxacin concentrations (0.078 mg/L). The genotoxicity assay detected a significant increase in genetic damage index up to 0.013 mg/L of ciprofloxacin. The here-tested ciprofloxacin concentrations, which are ecologically relevant, did not cause significant impacts concerning the life-history parameters of D. magna; however, at the same levels of ciprofloxacin an oxidative stress and genotoxic damage scenarios were recorded.

Performance and bacterial diversity of bioreactors used for simultaneous removal of sulfide, solids and organic matter from UASB reactor effluents.

Two bioreactors were investigated as an alternative to post-treatment of effluent from an upflow anaerobic sludge blanket (UASB) reactor treating domestic sewage, with an aim of oxidizing sulfide into elemental sulfur, and removal of solid and organic material. The bioreactors were operated at different hydraulic retention times (HRTs) (6, 4, and 2 h) and in the presence or absence (control) of packing material (polypropylene rings). Greater sulfide removal efficiencies - 75% (control reactor) and 92% (packed reactor) - were achieved in both reactors for an HRT of 6 h. Higher organic matter (COD) and solid (TSS) removal levels were observed in the packed reactor, which produced effluent with low COD (100 mg CODL-1) and TSS concentrations (30 mg TSSL-1). Denaturing gradient gel electrophoresis results revealed that a metabolically diverse bacterial community was present in both bioreactors, with sequences related to heterotrophic bacteria, sulfur bacteria (Thiocapsa, Sulfurimonas sp., Chlorobaculum sp., Chromatiales and Sulfuricellales), phototrophic purple non-sulfur bacteria (Rhodopseudomonas, Rhodocyclus sp.) and cyanobacteria. The packed reactor presented higher extracellular sulfur formation and potential for elemental sulfur recovery was seen. Higher efficiencies related to the packed reactor were attributed to the presence of packing material and higher cell retention time. The studied bioreactors seemed to be a simple and low-cost alternative for the post-treatment of anaerobic effluent.

Soft nanostructured films for directing the assembly of functional materials.

Lipids are a class of biological small molecules with hydrophilic and hydrophobic constituents forming the structural membranes in cells. Over the past century an extensive understanding of lipid biology and biophysics has been developed illuminating lipids as an intricate, highly tunable, and hierarchical soft-matter system. In addition to serving as cell membrane models, lipids have been investigated as microphase separated structures in aqueous solutions. In terms of applications lipids have been realized as powerful structural motifs for the encapsulation and cellular delivery of genetic material. More recently, lipids have also revealed promise as thin film materials, exhibiting long-range periodic nano-scale order and tunable orientation. In this review we summarize the pertinent understanding of lipid nanostructure development in bulk aqueous systems followed by the current and potential perturbations to these results induced by introduction of a substrate. These effects are punctuated by a summary of our published results in the field of lipid thin films with added nucleic acids and key results introducing hard materials into lipid nanostructured substrates.

Sensitivity and specificity of real-time PCR and bacteriological culture for francisellosis in farm-raised Nile tilapia (Oreochromis niloticus L.).

Despite the worldwide occurrence of Francisella noatunensis subsp. orientalis (Fno) infection in farmed tilapia, sensitivity and specificity estimates of commonly used diagnostic tests have not been reported. This study aimed to estimate the sensitivity and specificity of bacteriological culture and qPCR to detect Fno infection. We tested 559 fish, sampled from four farms with different epidemiological scenarios: (i) healthy fish in a hatchery free of Fno; (ii) targeted sampling of diseased fish with suggestive external clinical signs of francisellosis during an outbreak; (iii) convenience sampling of diseased and clinically healthy fish during an outbreak; and (iv) sampling of healthy fish in a cage farm without a history of outbreaks, but with francisellosis reported in other farms in the same reservoir. The qPCR had higher median sensitivity (range, 48.8-99.5%) than culture (range, 1.6-74.4%). Culture had a substantially lower median sensitivity (1.6%) than qPCR (48.8%) to detect Fno in carrier tilapia (farm 4). Median specificity estimates for both tests were >99.2%. The qPCR is the superior test for use in surveillance and monitoring programmes for francisellosis in farmed Nile tilapia, but both tests have high sensitivity and specificity which make them fit for use in the diagnosis of Fno outbreaks.

Natural coinfection by Streptococcus agalactiae and Francisella noatunensis subsp. orientalis in farmed Nile tilapia (Oreochromis niloticus L.).

Streptococcus agalactiae and Francisella noatunensis subsp. orientalis (Fno) are important pathogens for farm-raised tilapia worldwide. There are no reports of coinfection caused by S. agalactiae and Fno in fish. This study aimed to determine the aetiology of atypical mortalities in a cage farm of Nile tilapia and to characterize the genetic diversity of the isolates. Fifty-two fish were sampled and subjected to parasitological and bacteriological examination. The S. agalactiae and Fno isolates were genotyped using MLST and REP-PCR, respectively. Whole-genome sequencing was performed to confirm the MLST results. Seven fish were shown coinfected by S. agalactiae and Fno. Chronic hypoxia and a reduction in the water temperature were determined as risk factors for coinfection. Fno isolates were shown clonally related in REP-PCR. The MLST analysis revealed that the S. agalactiae isolates from seven coinfected fish were negative for the glcK gene; however, these were determined to be members of clonal complex CC-552. This is the first description of coinfection by S. agalactiae and Fno in farm-raised Nile tilapia. The coinfection was predisposed by chronic hypoxia and was caused by the main genotypes of S. agalactiae and Fno reported in Brazil. Finally, a new S. agalactiae genotype with glcK gene partially deleted was described.

Lactococcus garvieae outbreaks in Brazilian farms Lactococcosis in Pseudoplatystoma sp. - development of an autogenous vaccine as a control strategy.

This study evaluated the control of streptococcosis outbreaks in Brazil, isolated from diseased sorubim and identified as Lactococcus garvieae by genetic sequencing. This report determined the potential for lactococcosis control in sorubim Pseudoplatystoma sp. with two vaccines: an aqueous-based, whole-cell inactivated vaccine (bacterin) and an oil-adjuvanted bacterin. Their efficacy was evaluated at 30 days post-vaccination (d.p.v.) by challenge with L. garvieae, and the antibody production response at 15, 30 and 60 d.p.v. and the non-specific immune response were compared amongst treatments. High protection levels (P < 0.05) were achieved with the oil-adjuvanted vaccine with a relative percentage survival value of 81.7% at 30 d.p.v. Additionally, the oil-adjuvanted vaccine increased the immunogenicity of the bacterin as indicated by greater agglutination antibody titres from 15 until 60 d.p.v. This is the first report of a positive effect of vaccine administration on the specific immunity of sorubim, and the study showed that a specific antibody plays an important role in sorubim defence against lactococcosis because the innate immune responses were similar in all of the studied animals. These results demonstrated that oil-adjuvanted vaccine can be an effective alternative for the protection of sorubim from L. garvieae disease.

A comparative study of the effects of intramuscular administration of gonadorelin, mating and intrauterine infusion of either raw seminal plasma or seminal plasma purified ß-NGF on luteal development in llamas.

The aim of this study was to compare the effect of the intramuscular administration of 50 µg of gonadorelin acetate versus natural mating, intrauterine infusion (i.u.) of a physiological relevant dose of either raw llama seminal plasma (SP) or purified beta-nerve growth factor from seminal origin (spß-NGF) on ovulation rate and corpus luteum (CL) development and function in llamas. Females with a follicle (≥8 mm) were assigned to groups: (i) i.m. administration of 50 µg of gonadorelin acetate (GnRH; positive control; n = 4); (ii) single mating (mating; n = 6); (iii) i.u. infusion of 4 ml of llama SP (SP; n = 4); or (iv) i.u. infusion of 10 mg of spß-NGF contained in 4 ml of PBS (phosphate-buffered saline) (spß-NGF; n = 6). Ovaries were examined by power Doppler ultrasonography at 0, 1, 3, 6, 12 and 24 hr after treatment to determine preovulatory follicle vascularization area (VA), and additionally every 12 hr until Day 2 (Day of treatment = Day 0) to determine ovulation. Afterwards, ovaries were examined every other day until Day 8 to evaluate CL diameter and VA. Blood samples were collected on Days 0, 2, 4, 6 and 8 to determine plasma progesterone (P4) concentration. Ovulation rate did not differ (p = .7) among groups, but treatment affected (p < .0001) preovulatory follicle VA. Neither treatment administration nor treatment by time interaction affected (p ≥ .4) CL diameter, VA and plasma P4 concentration. Mating tended (p = .08) to increase CL VA when compared to the seminal plasma group by Day 8. Intrauterine administration of seminal plasma or spß-NGF does not increase CL size and function when compared to i.m. GnRH treatment, suggesting that the administration route of spß-NGF influences its luteotrophic effect in llamas.

Deficiency of fibroblast growth factor-inducible 14 (Fn14) preserves the filtration barrier and ameliorates lupus nephritis.

TNF ligand superfamily member 12, also known as TNF-related weak inducer of apoptosis (TWEAK), acts through its receptor, fibroblast growth factor-inducible 14 (Fn14), to mediate several key pathologic processes involved in tissue injury relating to lupus nephritis. To explore the potential for renal protection in lupus nephritis by targeting this pathway, we introduced the Fn14 null allele into the MRL-lpr/lpr lupus mouse strain. At 26-38 weeks of age, female Fn14-knockout MRL-lpr/lpr mice had significantly lower levels of proteinuria compared with female wild-type MRL-lpr/lpr mice. Furthermore, Fn14-knockout mice had significantly improved renal histopathology accompanied by attenuated glomerular and tubulointerstitial inflammation. There was a significant reduction in glomerular Ig deposition in Fn14-knockout mice, despite no detectable differences in either serum levels of antibodies or splenic immune cell subsets. Notably, we found that the Fn14-knockout mice displayed substantial preservation of podocytes in glomeruli and that TWEAK signaling directly damaged barrier function and increased filtration through podocyte and glomerular endothelial cell monolayers. Our results show that deficiency of the Fn14 receptor significantly improves renal disease in a spontaneous lupus nephritis model through prevention of the direct injurious effects of TWEAK on the filtration barrier and/or modulation of cytokine production by resident kidney cells. Thus, blocking the TWEAK/Fn14 axis may be a novel therapeutic intervention in immune-mediated proliferative GN.

Neuropsychiatric systemic lupus erythematosus persists despite attenuation of systemic disease in MRL/lpr mice.

BACKGROUND: Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease marked by both B and T cell hyperactivity which commonly affects the joints, skin, kidneys, and brain. Neuropsychiatric disease affects about 40 % of SLE patients, most frequently manifesting as depression, memory deficits, and general cognitive decline. One important and yet unresolved question is whether neuropsychiatric SLE (NPSLE) is a complication of systemic autoimmunity or whether it is primarily driven by brain-intrinsic factors. METHODS: To dissect the relative contributions of the central nervous system from those of the hematopoietic compartment, we generated bone marrow chimeras between healthy control (MRL/+) and lupus-prone MRL/Tnfrsf6 (lpr/lpr) mice (MRL/+ → MRL/lpr), as well as control chimeras. After bone marrow reconstitution, mice underwent extensive behavioral testing, analysis of brain tissue, and histological assessment. RESULTS: Despite transfer of healthy MRL/+ bone marrow and marked attenuation of systemic disease, we found that MRL/+ → MRL/lpr mice had a behavioral phenotype consisting of depressive-like behavior and visuospatial memory deficits, comparable to MRL/lpr → MRL/lpr control transplanted mice and the behavioral profile previously established in MRL/lpr mice. Moreover, MRL/+ → MRL/lpr chimeric mice displayed increased brain RANTES expression, neurodegeneration, and cellular infiltration in the choroid plexus, as well as blood brain barrier disruption, all in the absence of significant systemic autoimmunity. CONCLUSIONS: Chimeric MRL/+ → MRL/lpr mice displayed no attenuation of the behavioral phenotype found in MRL/lpr mice, despite normalized serum autoantibodies and conserved renal function. Therefore, neuropsychiatric disease in the MRL/lpr lupus-prone strain of mice can occur absent any major contributions from systemic autoimmunity.

Macrophage depletion ameliorates nephritis induced by pathogenic antibodies.

Kidney involvement affects 40-60% of patients with lupus, and is responsible for significant morbidity and mortality. Using depletion approaches, several studies have suggested that macrophages may play a key role in the pathogenesis of lupus nephritis. However, "off target" effects of macrophage depletion, such as altered hematopoiesis or enhanced autoantibody production, impeded the determination of a conclusive relationship. In this study, we investigated the role of macrophages in mice receiving rabbit anti-glomerular antibodies, or nephrotoxic serum (NTS), an experimental model which closely mimics the immune complex mediated disease seen in murine and human lupus nephritis. GW2580, a selective inhibitor of the colony stimulating factor-1 (CSF-1) receptor kinase, was used for macrophage depletion. We found that GW2580-treated, NTS challenged mice did not develop the increased levels of proteinuria, serum creatinine, and BUN seen in control-treated, NTS challenged mice. NTS challenged mice exhibited significantly increased kidney expression of inflammatory cytokines including RANTES, IP-10, VCAM-1 and iNOS, whereas GW2580-treated mice were protected from the robust expression of these inflammatory cytokines that are associated with lupus nephritis. Quantification of macrophage related gene expression, flow cytometry analysis of kidney single cell suspensions, and immunofluorescence staining confirmed the depletion of macrophages in GW2580-treated mice, specifically within renal glomeruli. Our results strongly implicate a specific and necessary role for macrophages in the development of immune glomerulonephritis mediated by pathogenic antibodies, and support the development of macrophage targeting approaches for the treatment of lupus nephritis.

New hosts and genetic diversity of Flavobacterium columnare isolated from Brazilian native species and Nile tilapia.

Flavobacterium columnare is responsible for disease outbreaks in freshwater fish farms. Several Brazilian native fish have been commercially exploited or studied for aquaculture purposes, including Amazon catfish Leiarius marmoratus × Pseudoplatystoma fasciatum and pacamã Lophiosilurus alexandri. This study aimed to identify the aetiology of disease outbreaks in Amazon catfish and pacamã hatcheries and to address the genetic diversity of F. columnare isolates obtained from diseased fish. Two outbreaks in Amazon catfish and pacamã hatcheries took place in 2010 and 2011. Four F. columnare strains were isolated from these fish and identified by PCR. The disease was successfully reproduced under experimental conditions for both fish species, fulfilling Koch's postulates. The genomovar of these 4 isolates and of an additional 11 isolates from Nile tilapia Oreochromis niloticus was determined by 16S rRNA restriction fragment length polymorphism PCR. The genetic diversity was evaluated by phylogenetic analysis of the 16S rRNA gene and repetitive extragenic palindromic PCR (REP-PCR). Most isolates (n = 13) belonged to genomovar II; the remaining 2 isolates (both from Nile tilapia) were assigned to genomovar I. Phylogenetic analysis and REP-PCR were able to demonstrate intragenomovar diversity. This is the first report of columnaris in Brazilian native Amazon catfish and pacamã. The Brazilian F. columnare isolates showed moderate diversity, and REP-PCR was demonstrated to be a feasible method to evaluate genetic variability in this bacterium.

Characterization of Weissella ceti infections in Brazilian rainbow trout, Oncorhynchus mykiss (Walbaum), farms and development of an oil-adjuvanted vaccine.

Weissella ceti is an emerging bacterial pathogen that affects rainbow trout, Oncorhynchus mykiss (Walbaum), farms. The aims of this study were to genotype W. ceti strains isolated from distinct geographical origins and to determine the efficacy of an oil-adjuvanted vaccine against the disease. Between 2010 and 2012, outbreaks were recorded in five Brazilian farms, and 34 W. ceti isolates were genetically characterized by repetitive extragenic palindromic PCR, enterobacterial repetitive intergenic consensus sequences PCR and pulsed-field gel electrophoresis. Two different W. ceti vaccines were tested: an aqueous-based whole-cell inactivated vaccine (bacterin) and oil-adjuvanted vaccine. Their efficacy was evaluated in rainbow trout at 30 and 60 days post-vaccination (d.p.v.). W. ceti was found to be a highly homogeneous population in Brazil, with clonally related genotypes. Oil-adjuvanted vaccine exhibited the best (P < 0.05) protection against disease, reaching relative percentage survival (RPS)values of 92% at 30 and 60 d.p.v. Bacterin resulted in RPS values of 67% and 58% at day 30 and 60, respectively. The oil-adjuvanted vaccine provided effective protection against W. ceti infection in rainbow trout.

BRAF overexpression is associated with BRAF V600E mutation in papillary thyroid carcinomas.

A common mutation in the BRAF gene, comprising the T1799A nucleotide transversion, which leads to the V600E amino acid substitution in the BRAF protein, has been observed in about 50% of papillary thyroid carcinomas (PTCs). However, BRAF protein expression has been rarely examined in such tumors. Clinical studies have shown important associations between BRAF mutation and clinical parameters in PTC, such as progression, invasion, and recurrence. The aim of this study was to evaluate the association between BRAF protein overexpression and the BRAF V600E mutation in a group of PTC patients. The study group included 116 patients with PTC from Araújo Jorge Hospital, Goiânia, Goiás, Brazil. Immunohistochemistry was utilized to analyze BRAF protein expression. Presence of the BRAF V600E mutation was determined by polymerase chain reaction amplification and restriction fragment length polymorphism, and confirmed by direct sequencing. The chi-square test with Yates correction and the Fisher exact test were used for statistical analysis. BRAF overexpression was detected in 55 patients with PTC (47.4%) and the BRAF V600E mutation was observed in 74 patients (63.8%). In the studied group, significant associations were observed between the BRAF V600E mutation and BRAF protein overexpression (P = 0.0115), and also between BRAF overexpression and extra-thyroid extension of the tumor (P = 0.0111). This study demonstrated a significant association between BRAF overexpression and the BRAF V600E mutation in PTC, highlighting the importance of these molecular events in the process of PTC carcinogenesis.

Toward a working definition of C3 glomerulopathy by immunofluorescence.

Precise immunofluorescence criteria for C3 glomerulopathy remain to be defined. Here we tested hierarchical immunofluorescence criteria with varying stringency for C3 glomerulopathy in a cohort with dense deposit disease as the gold standard and then applied these criteria to analyze the incidence of C3 glomerulopathy in membranoproliferative glomerulonephritis (MPGN) types 1 and 3. Among 319 archived cases of primary MPGN types 1-3, immunofluorescence reports were retrospectively coded as glomerular deposits of the following: C3 only; C3 dominant with trace or 1+ immunoglobulin (Ig)M only; and C3 dominant and at least two orders of intensity stronger than any combination of IgG, IgM, IgA, and C1q. The most restrictive criteria of 'C3 only' captured only half of the cases with dense deposit disease (compared with 8% of type 1 and 10% of type 3). Adding the most liberal definition identified 88% of those with dense deposit disease (compared with 31% of type 1 and 39% of type 3). The unaccounted 12% had stronger intensity of Ig staining, but it never exceeded the intensity of C3. Among MPGN type 3, 90% of C3 glomerulopathy cases were the Strife and Anders variant. Repeat biopsies in C3 glomerulopathy revealed a change in immunofluorescence pattern in 10 of 23 biopsies. The prevalence of low serum C3 and/or low C4 did not significantly differ among the three immunofluorescence criteria. Thus, 'C3 only' is an impractical definition of C3 glomerulopathy, and we propose a definition of C3 dominant and at least two orders of magnitude more intense than any other immune reactant, which requires validation by alternative pathway evaluation. These criteria provide a framework for identifying patients most likely to benefit from investigations of alternative complement pathway dysregulation.