The initial development of intestinal microbiota in poultry plays an important role in production performance, overall health and resistance against microbial infections. Multiplexed sequencing of ...16S ribosomal RNA gene amplicons is often used in studies, such as feed intervention or antimicrobial drug trials, to determine corresponding effects on the composition of intestinal microbiota. However, considerable variation of intestinal microbiota composition has been observed both within and across studies. Such variation may in part be attributed to technical factors, such as sampling procedures, sample storage, DNA extraction, the choice of PCR primers and corresponding region to be sequenced, and the sequencing platforms used. Furthermore, part of this variation in microbiota composition may also be explained by different host characteristics and environmental factors. To facilitate the improvement of design, reproducibility and interpretation of poultry microbiota studies, we have reviewed the literature on confounding factors influencing the observed intestinal microbiota in chickens. First, it has been identified that host-related factors, such as age, sex, and breed, have a large effect on intestinal microbiota. The diversity of chicken intestinal microbiota tends to increase most during the first weeks of life, and corresponding colonization patterns seem to differ between layer- and meat-type chickens. Second, it has been found that environmental factors, such as biosecurity level, housing, litter, feed access and climate also have an effect on the composition of the intestinal microbiota. As microbiota studies have to deal with many of these unknown or hidden host and environmental variables, the choice of study designs can have a great impact on study outcomes and interpretation of the data. Providing details on a broad range of host and environmental factors in articles and sequence data repositories is highly recommended. This creates opportunities to combine data from different studies for meta-analysis, which will facilitate scientific breakthroughs toward nutritional and husbandry associated strategies to improve animal health and performance.
This study evaluated predictors for patient and renal survival in patients with ANCA-associated vasculitis (AAV) with and without renal involvement.
There were 273 consecutive AAV patients from ...January 1990 until December 2007 who were followed until death, loss to follow-up, or December 2010. Based on organ involvement, patients were divided into renal (n=212) and nonrenal groups (n=61). The primary end point was ESRD requiring renal replacement therapy (RRT) or renal transplantation or death.
Patient survival was significantly better in the nonrenal group compared with the renal group (hazard ratio, 0.55; 95% confidence interval, 0.33 to 0.92; P=0.02). In the renal group, renal survival was significantly worse in MPO-ANCA-positive patients (n=65) compared with PR3-ANCA-positive patients (n=138) (hazard ratio, 2.1; 95% confidence interval, 1.11 to 3.8; P=0.01). Of 48 patients who needed RRT at diagnosis, 11 patients (23%) died within 6 months and 14 patients (29%) did not regain renal function. Of all 23 patients who regained renal function after RRT, 7 patients (30%) were temporarily dialysis independent and needed dialysis later (range, 13-63 months). Five patients had a renal relapse in the 6 months before restart of RRT. Of all 203 PR3-ANCA-positive and MPO-ANCA-positive patients with renal involvement, 12 patients (6%) developed ESRD during follow-up. These patients were classified as CKD stage 4 or 5 after initial treatment and eight patients had a renal relapse before becoming dialysis dependent.
AAV patients with renal involvement who needed RRT had the worst survival probability. In multivariate analysis, the only major determinants for long-term renal survival were renal function at 6 months and renal relapses.
Kidney histopathology in lethal human sepsis Aslan, Adnan; van den Heuvel, Marius C; Stegeman, Coen A ...
Critical care (London, England),
12/2018, Volume:
22, Issue:
1
Journal Article
Peer reviewed
Open access
The histopathology of sepsis-associated acute kidney injury (AKI) in critically ill patients remains an understudied area. Previous studies have identified that acute tubular necrosis (ATN) is not ...the only driver of sepsis-AKI. The focus of this study was to identify additional candidate processes that may drive sepsis-AKI. To do this we immunohistochemically characterized the histopathological and cellular features in various compartments of human septic kidneys.
We studied the following histopathological features: leukocyte subsets, fibroblast activation, cellular proliferation, apoptosis, and fibrin deposition in the glomerulus and the tubulointerstitium in human post-mortem kidney biopsy tissue. Biopsy tissue samples from 27 patients with sepsis-AKI were collected 33 min (range 24-150) after death in the ICU. The unaffected part of the kidneys from 12 patients undergoing total nephrectomy as a result of renal carcinoma served as controls.
Immunohistochemical analysis revealed the presence of more neutrophils and macrophages in the glomeruli and more neutrophils in the tubulointerstitium of renal tissue from patients with sepsis compared to control renal tissue. Type II macrophages were predominant, with some macrophages expressing both type I and type II markers. In contrast, there were almost no macrophages found in control kidneys. The number of activated (myo)fibroblasts was low in the glomeruli of sepsis-AKI kidneys, yet this was not observed in the tubulointerstitium. Cell proliferation and fibrin deposition were more pronounced in the glomeruli and tubulointerstitium of sepsis-AKI than in control kidneys.
The extensive heterogeneity of observations among and within patients emphasizes the need to thoroughly characterize patients with sepsis-AKI in a large sample of renal biopsy tissue from patients with sepsis.
The antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) comprise granulomatosis with polyangiitis (GPA), primarily associated with antibodies to proteinase 3 (PR3-ANCA); ...microscopic polyangiitis (MPA); and eosinophilic granulomatosis with polyangiitis (EGPA), both principally associated with antibodies to myeloperoxidase (MPO-ANCA). Genetic and environmental factors are involved in their etiopathogenesis, with a possible role for silica exposure in AAVs and Staphylococcus aureus infection in GPA. The distinct associations of PR3-ANCA and MPO-ANCA with different HLA class II antigens, which are stronger than those with the associated diseases, suggest a pathogenic role for those ANCAs and indicate that GPA and MPA are different diseases. Both in vitro and in vivo experimental data have shown that MPO-ANCA can induce necrotizing small-vessel vasculitis and glomerulonephritis. The additional role of the alternative pathway of complement activation has been demonstrated in human and experimental pathology. Also, T cells seem to be involved in lesion development, particularly in the kidney. Granuloma formation, as seen in PR3-ANCA–associated GPA, is not well explained by the presence of autoantibodies in experimental models. Here, T cells seem crucial. Recently obtained insights into the pathogenesis of AAVs have led to more targeted treatment of these life-threatening diseases.
Poly(ADP-ribose)ylation (PARylation) by PAR polymerase 1 (PARP1) and PARylation removal by poly(ADP-ribose) glycohydrolase (PARG) critically regulate DNA damage responses; yet, conflicting reports ...obscure PARG biology and its impact on cancer cell resistance to PARP1 inhibitors. Here, we found that PARG expression is upregulated in many cancers. We employed chemical library screening to identify and optimize methylxanthine derivatives as selective bioavailable PARG inhibitors. Multiple crystal structures reveal how substituent positions on the methylxanthine core dictate binding modes and inducible-complementarity with a PARG-specific tyrosine clasp and arginine switch, supporting inhibitor specificity and a competitive inhibition mechanism. Cell-based assays show selective PARG inhibition and PARP1 hyperPARylation. Moreover, our PARG inhibitor sensitizes cells to radiation-induced DNA damage, suppresses replication fork progression and impedes cancer cell survival. In PARP inhibitor-resistant A172 glioblastoma cells, our PARG inhibitor shows comparable killing to Nedaplatin, providing further proof-of-concept that selectively inhibiting PARG can impair cancer cell survival.
Granulomatosis with polyangiitis (GPA) is an autoimmune disease affecting mainly small blood vessels. B-cells are important in the GPA pathogenesis as precursors of autoantibody-producing cells but ...likely also contribute (auto)antibody-independently. This has been underlined by the effectiveness of B-cell-depletion (with Rituximab) in inducing and maintaining disease remission. Mycophenolate-mofetil (MMF) and azathioprine (AZA) are immunosuppressive therapies frequently used in GPA-patients. Interestingly, MMF-treated GPA-patients are more prone to relapses than AZA-treated patients, while little is known about the influence of these drugs on B-cells. We investigated whether MMF or AZA treatment (or their active compounds) alters the circulating B-cell subset distribution and has differential effects on in vitro B-cell proliferation and cytokine production in GPA-patients that might underlie the different relapse rate. Circulating B-cell subset frequencies were determined in samples from AZA-treated (n = 13), MMF-treated (n = 12), untreated GPA-patients (n = 19) and matched HCs (n = 41). To determine the ex vivo effects of the active compounds of MMF and AZA, MPA and 6-MP respectively, on B-cell proliferation and cytokine production, PBMCs of untreated GPA-patients (n = 29) and matched HCs (n = 30) were cultured for 3-days in the presence of CpG-oligodeoxynucleotides (CpG) with MPA or 6-MP. After restimulation (with phorbol myristate acetate, calcium-ionophore), cytokine-positive B-cell frequencies were measured. Finally, to assess the effect of MMF or AZA treatment on in vitro B-cell proliferation and cytokine production, PBMCs of MMF-treated (n = 18), and AZA-treated patients (n = 28) and HCs (n = 41) were cultured with CpG. The memory B-cell frequency was increased in AZA- compared to MMF-treated patients, while no other subset was different. The active compounds of MMF and AZA showed in vitro that MPA decreased B-cell proliferation in GPA-patients and HCs. B-cell proliferation in MMF- and AZA-treated patients was not different. Finally, the IL-6.sup.+ B-cell frequency was decreased by MPA compared to 6-MP. No differences in IL-10.sup.+, IL-6.sup.+ or TNFalpha.sup.+ B-cell proportions or proliferation were found in MMF- and AZA-treated patients. Our results indicate that MMF could be superior to AZA in inhibiting B-cell cytokine production in GPA-patients. Future studies should assess the effects of these immunosuppressive drugs on other immune cells to elucidate mechanisms underlying the potential differences in relapse rates.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Oxalate nephropathy, due to secondary hyperoxaluria has widely been described in gastrointestinal diseases. However, reports of oxalate nephropathy in newly diagnosed celiac disease are rare. A ...72-year-old Caucasian male presented to the hospital with abdominal discomfort and acute renal insufficiency with a creatinine of 290 µmol/L. The clinical course, laboratory results and urinalysis were suspect for tubular injury. Renal biopsy showed calcium oxalate depositions. Elevated plasma and urine oxalate levels established the diagnosis oxalate nephropathy. The abdominal complaints with steatorrhea and positive anti-tissue transglutaminase antibodies were diagnosed as celiac disease, which was confirmed after duodenal biopsies. Treatment with prednisone, and gluten-free, low oxalate and normal calcium diet, lowered the plasma oxalate levels and improved his renal function. Decreased absorption of free fatty acids can lead to increased free oxalate in the colon due to the binding of free fatty acids to calcium, preventing the formation of the less absorbable calcium oxalate in the colon. Oxalate dispositions in the kidney can lead to acute tubular injury and chronic renal insufficiency. Celiac disease is therefore one of the intestinal diseases that can lead to hyperoxaluria and oxalate nephropathy.
During autumn-winter 2016-2017, highly pathogenic avian influenza A(H5N8) viruses caused mass die-offs among wild birds in the Netherlands. Among the ≈13,600 birds reported dead, most were tufted ...ducks (Aythya fuligula) and Eurasian wigeons (Anas penelope). Recurrence of avian influenza outbreaks might alter wild bird population dynamics.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To describe renal outcomes of the lupus nephritis (LN) population of the University Medical Centre Groningen (UMCG) in the Netherlands and to identify predictors for renal flares and long-term renal ...outcome in daily clinical practice.
A retrospective analysis of biopsy-proven LN patients with induction and maintenance treatment in the UMCG between 1982 and 2016 was performed. Data were collected at time of diagnosis, after 6 months and every year up to 10 years after diagnosis. Outcome measures were renal relapse (biopsy proven), progression to chronic kidney disease (CKD) stage 3 or 4 and chronic renal replacement therapy. The ability of serum creatinine, proteinuria, creatinine clearance, serum anti-double stranded DNA (anti-dsDNA) antibodies, serum complement 3 (C3) and serum complement 4 (C4), as well as biographic data and histopathological class to predict long-term renal outcome was assessed.
Seventy-one patients were included, with median follow-up of 120 months (IQR 48-120 months). During follow-up - up to 10 years - twenty-one (30%) patients experienced at least one relapse. Eleven (15%) patients had CKD stage 3 or 4, of whom eight showed persistent CKD since baseline and two (3%) patients required chronic renal replacement therapy. At baseline, low levels of serum C3 were a significant predictor of renal relapse. Low levels of C3 and C4 at 6 and 12 and proteinuria and high levels of anti-dsDNA at 12 months were significant predictors of renal relapse. At baseline, 6 months and 12 months serum creatinine and creatinine clearance were significant predictors for persistent or newly developed CKD 3 or 4, and need for chronic renal replacement therapy.
Almost one-third of LN patients experience at least one renal relapse during long-term follow up, but only 3% need chronic renal replacement therapy. Our data suggests that early serological remission is associated with a low risk of renal relapse. Decreased renal function at onset and the first year after diagnosis is predictive for decreased renal function at a later stage.
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