Host immunity and KLF 11 deficiency together promote fibrosis in a mouse model of endometriosis

BACKGROUND

Endometriosis is a debilitating disease typically characterized by prolific fibrotic scarring. Earlier we reported downregulation of two transcription factors belonging TGF-βR signaling pathway Sp/Krüppel-like factor 11 (KLF11) and 10 (KLF10) in human endometriosis lesions. Here we investigated the role of these nuclear factors and immunity in the scaring fibrosis associated with endometriosis.

METHODS

We used a well characterized experimental mouse model of endometriosis. WT, KLF10 or KLF11 deficient mice were compared. The lesions were evaluated histologically, fibrosis was quantified with Masons' Trichome staining, immune-infiltrates were quantified by immunohistochemistry, peritoneal adhesions were score, gene expression was evaluated by bulk RNA sequencing.

RESULTS

Intense fibrotic reactions and large changes in gene expression were detected in KLF11 deficient implants associated with squamous metaplasia of the ectopic endometrium, as compared to KLF10 deficient or WT implants. Fibrosis was mitigated with pharmacologic agents that blocked histone acetylation or TGF-βR signaling or with genetic deficiency for SMAD3. The lesions were richly infiltrated with T-cells, regulatory T-cells, and innate immune cells. Fibrosis was exacerbated when implants expressed ectopic genes implicating autoimmunity as a major factor contributing to the scaring fibrosis.

CONCLUSIONS

Our findings identify KLF11 and TGF-βR signaling as cell intrinsic mechanisms and autoimmune responses as cell extrinsic mechanisms of scaring fibrosis in ectopic endometrium lesions.

GENERAL SIGNIFICANCE

Immunological factors associated with inflammation and tissue repair drive scaring fibrosis in experimental endometriosis, providing the rationale for immune therapy of endometriosis.

Automated scoring of total inflammation in renal allograft biopsies

BACKGROUND

Computer-assisted scoring is gaining prominence in the evaluation of renal histology; however, much of the focus has been on identifying larger objects such as glomeruli. Total inflammation impacts graft outcome, and its quantification requires tools to identify objects at the cellular level or smaller. The goal of the current study was to use CD45 stained slides coupled with image analysis tools to quantify the amount of non-glomerular inflammation within the cortex.

METHODS

Sixty renal transplant whole slide images were used for digital image analysis. Multiple thresholding methods using pixel intensity and object size were used to identify inflammation in the cortex. Additionally, convolutional neural networks were used to separate glomeruli from other objects in the cortex. This combined measure of inflammation was then correlated with rescored Banff total inflammation classification and outcomes.

RESULTS

Identification of glomeruli on biopsies had high fidelity (mean pixelwise dice coefficient of .858). Continuous total inflammation scores correlated well with Banff rescoring (maximum Pearson correlation .824). A separate set of thresholds resulted in a significant correlation with alloimmune graft loss.

CONCLUSIONS

Automated scoring of inflammation showed a high correlation with Banff scoring. Digital image analysis provides a powerful tool for analysis of renal pathology, not only because it is reproducible and can be automated, but also because it provides much more granular data for studies.

MO075KLF11 DEFICIENCY ENHANCES CHEMOKINE GENERATION AND INJURY IN MURINE UNILATERAL URETERIC OBSTRUCTION

Background and Aims

Kruppel-like factors (KLFs) comprise a family of zinc-finger transcription factors that play a critical role in development, proliferation, and regeneration following injury. There are over 17 members of this family; recent studies have shown that KLF family members regulate podocyte differentiation, preservation of the glomerular filtration barrier, and regulation of mitochondrial function. However, a role for KLF11 in renal pathophysiology has not been previously established.

Method

Wild-type (WT) and KLF11 knockout (KO) mice were subjected to unilateral ureteric obstruction (UUO), a well-established model of renal inflammation and fibrosis; controls included mice subjected to manipulation of the ureter without ligation. Kidneys were harvested after 9 days (n=8 animals per group). Semiquantitative histopathologic analysis of renal atrophy, fibrosis, and inflammation was performed in a blinded fashion. Gene expression analysis was performed on renal cortex employing the Pathway Detect RNA array and RNASeq.

Results

In UUO, renal atrophy was more severe in KLF11 KO mice than WT mice (p<0.001). Deposition of collagen, as assessed by quantitative analysis of Sirus Red stained sections, was greater in KLF11 KO mice, compared to WT mice subjected to UUO; COL3A1 expression was also increased (p<0.05). Atrophy was associated with an increase in F4/80+ (p<0.01) and CD206+ macrophages (p<0.05), but not CD3+ T cells in KLF11 KO vs. WT mice. Induction of CC chemokines, including CCL2, CCL5, CCL7, CCL12, and CCL2 as well as CCR2 was significantly higher in KLF11 KO versus WT mice subjected to UUO (all p<0.001). Expression of NF-kB (p<0.01) and TNF alpha (p<0.01), but not IL-1 beta, IL-6, or IL-10 were significantly higher in KLF11 KO than WT mice with UUO. Expression of TGF-beta 1, Smad2, and Smad3 were also higher in KLF11 KO mice than WT mice with UUO (p<0.05).

Conclusion

Renal injury in UUO is exacerbated in KLF11 KO mice, compared to WT mice. Injury is associated with increased macrophage influx and production of pro-inflammatory chemokines. Future studies will determine how KLF11 deficiency directs transcription of pro-inflammatory and pro-fibrotic genes.

i-IFTA and chronic active T cell-mediated rejection: A tale of 2 (DeKAF) cohorts

Inflammation in areas of fibrosis (i-IFTA) in posttransplant biopsies is part of the diagnostic criteria for chronic active TCMR (CA TCMR -- i-IFTA ≥ 2, ti ≥ 2, t ≥ 2). We evaluated i-IFTA and CA TCMR in the DeKAF indication biopsy cohorts: prospective (n = 585, mean time to biopsy = 1.7 years); cross-sectional (n = 458, mean time to biopsy = 7.8 years). Grouped by i-IFTA scores, the 3-year postbiopsy DC-GS is similar across cohorts. Although a previous acute rejection episode (AR) was more common in those with i-IFTA on biopsy, the majority of those with i-IFTA had not had previous AR. There was no association between type of previous AR (AMR, TCMR) and presence of i-IFTA. In both cohorts, i-IFTA was associated with markers of both cellular (increased Banff i, t, ti) and humoral (increased g, ptc, C4d, DSA) activity. Biopsies with i-IFTA = 1 and i-IFTA ≥ 2 with concurrent t ≥ 2 and ti ≥ 2 had similar DC-GS. These results suggest that (a) i-IFTA≥1 should be considered a threshold for diagnoses incorporating i-IFTA, ti, and t; (b) given that i-IFTA ≥ 2,t ≥ 2, ti ≥ 2 can occur in the absence of preceding TCMR and that the component histologic scores (i-IFTA,t,ti) each indicate an acute change (albeit i-IFTA on the nonspecific background of IFTA), the diagnostic category "CA TCMR" should be reconsidered.

Recurrence of DNAJB9-Positive Fibrillary Glomerulonephritis After Kidney Transplantation: A Case Series

RATIONALE & OBJECTIVE

Fibrillary glomerulonephritis (FGN) is a rare glomerular disease that often progresses to kidney failure requiring kidney replacement therapy. We have recently identified a novel biomarker of FGN, DnaJ homolog subfamily B member 9 (DNAJB9). In this study, we used sequential protocol allograft biopsies and DNAJB9 staining to help characterize a series of patients with native kidney FGN who underwent kidney transplantation.

STUDY DESIGN

Case series.

SETTING & PARTICIPANTS

Between 1996 and 2016, kidney transplantation was performed on 19 patients with a reported diagnosis of FGN in their native/transplant kidneys. Using standard diagnostic criteria and DNAJB9 staining, we excluded 5 patients (4 atypical cases diagnosed as possible FGN and 1 donor-derived FGN). Protocol allograft biopsies had been performed at 4, 12, 24, 60, and 120 months posttransplantation. DNAJB9 immunohistochemistry was performed using an anti-DNAJB9 rabbit polyclonal antibody. Pre- and posttransplantation demographic and clinical characteristics were collected. Summary statistical analysis was performed, including nonparametric statistical tests.

OBSERVATIONS

The 14 patients with FGN had a median posttransplantation follow-up of 5.7 (IQR, 2.9-13.8) years. 3 (21%) patients had recurrence of FGN, detected on the 5- (n=1) and 10-year (n=2) allograft biopsies. Median time to recurrence was 10.2 (IQR, 5-10.5) years. Median levels of proteinuria and iothalamate clearance at the time of recurrence were 243mg/d and 56mL/min. The remaining 11 patients had no evidence of histologic recurrence on the last posttransplantation biopsy, although the median time of follow-up was significantly less at 4.4 (IQR, 2.9-14.4) years. 3 (21%) patients had a monoclonal protein detectable in serum obtained pretransplantation; none of these patients had recurrent FGN.

LIMITATIONS

Small study sample and shorter follow-up time in the nonrecurrent versus recurrent group.

CONCLUSIONS

In this series, FGN had an indolent course in the kidney allograft in that detectable histologic recurrence did not appear for at least 5 years posttransplantation.

Immune profiles in experimental two-Kidney-one-cuff (2K-1C) model of renovascular hypertension that predicts reversible versus irreversible renal injury

Renal artery stenosis is common in the elderly population; biomarkers that predict response to restoration of blood flow have not been previously established.

Methods

We have previously shown in murine model that cuff removal 7 days (7D Cuff-off) after initial placement on the renal artery results in reversible injury whereas cuff removal 14 days (14D Cuff-off) after placement results in irreversible renal injury, when assessed at 28 days after initial surgery. Positive and negative controls consisted of cuff placement for 28 days (28D) and sham surgeries respectively. We performed RNASeq on whole renal cortex to identify innate immune pathways that correlate with reversible versus irreversible injury. Data were normalized to appropriate sham controls in all the groups. Induction of greater than log2 ratio > 2 and p < 0.00001 were considered significant (following adjustment for multiple comparisons).

Results

As assessed by RNASeq, progression of renal disease (14D Cuff-off & 28D mice) was associated with persistent upregulation of genes associated with T cell signaling and macrophage polarization compared to reversible injury (7D Cuff off). Upregulated genes included but not limited to: CCL5, CCR5, CCL2, CXCL1, CXCL9, CXCL10, CXCR3, TLR2, KLF6, CD74, CD4, CD14, CD44, CD83, CD84, IL1R1, IL1B, SPP1, AIF1, SLC7A2, TRAF1, S100A4, SLC9A9, CRIP1, CLEC7A, CLEC10A, EGR2, MGL2, SOCS2, CTLA2B, and FCGR1.

Conclusion

We have identified genes associated with T cell and macrophage activation that were down regulated in the 7D Cuff-off versus 14D Cuff-off and 28D mice; future studies in isolated T cells and macrophages will determine whether these genes represents biomarker(s) of renal disease progression in 2K-1C renovascular hypertension.

Targeting senescent cells alleviates obesity-induced metabolic dysfunction

Adipose tissue inflammation and dysfunction are associated with obesity-related insulin resistance and diabetes, but mechanisms underlying this relationship are unclear. Although senescent cells accumulate in adipose tissue of obese humans and rodents, a direct pathogenic role for these cells in the development of diabetes remains to be demonstrated. Here, we show that reducing senescent cell burden in obese mice, either by activating drug-inducible "suicide" genes driven by the p16Ink4a promoter or by treatment with senolytic agents, alleviates metabolic and adipose tissue dysfunction. These senolytic interventions improved glucose tolerance, enhanced insulin sensitivity, lowered circulating inflammatory mediators, and promoted adipogenesis in obese mice. Elimination of senescent cells also prevented the migration of transplanted monocytes into intra-abdominal adipose tissue and reduced the number of macrophages in this tissue. In addition, microalbuminuria, renal podocyte function, and cardiac diastolic function improved with senolytic therapy. Our results implicate cellular senescence as a causal factor in obesity-related inflammation and metabolic derangements and show that emerging senolytic agents hold promise for treating obesity-related metabolic dysfunction and its complications.

Late graft failure after kidney transplantation as the consequence of late versus early events

Beyond the first posttransplant year, 3% of kidney transplants fail annually. In a prospective, multicenter cohort study, we tested the relative impact of early versus late events on risk of long-term death-censored graft failure (DCGF). In grafts surviving at least 90 days, early events (acute rejection [AR] and delayed graft function [DGF] before day 90) were recorded; serum creatinine (Cr) at day 90 was defined as baseline. Thereafter, a 25% rise in serum Cr or new-onset proteinuria triggered graft biopsy (index biopsy, IBx), allowing comparison of risk of DCGF associated with early events (AR, DGF, baseline serum Cr >2.0 mg/dL) to that associated with later events (IBx). Among 3678 patients followed for 4.7 ± 1.9 years, 753 (20%) had IBx at a median of 15.3 months posttransplant. Early AR (HR = 1.77, P < .001) and elevated Cr at Day 90 (HR = 2.56, P < .0001) were associated with increased risk of DCGF; however, later-onset dysfunction requiring IBx had far greater impact (HR = 13.8, P < .0001). At 90 days, neither clinical characteristics nor early events distinguished those who subsequently did or did not undergo IBx or suffer DCGF. To improve long-term kidney allograft survival, management paradigms should promote prompt diagnosis and treatment of both early and later events.

Mesenchymal cell effect on the immune response in renovascular hypertension (INC1P.352)

Atherosclerotic renal artery sclerosis (RAS) is a significant public health concern, affecting 7% of the population over 65 years old and conveying an increased risk for cardiovascular as well as renal disease. Recent reports have failed to show a benefit of renal artery stenting to treat RAS. We tested the hypothesis that mesenchymal stem cells (MSC) slow the progression of renal injury by reducing inflammation. MSCs were isolated and cultured from murine adipocyte tissue and injected via the carotid artery into the animals 4 weeks after inducing RAS, a time at which the stenotic kidney has undergone severe atrophy. Conjugated microsphere labeling and flow cytometry confirmed that the MSCs migrate to the stenotic kidney. Half of the treatment group demonstrated a 90% reduction in atrophy and significantly lower level of regulatory T cell (Treg) infiltration while the other half demonstrated no change when compared to vehicle treated RAS mice. Array analysis showed a significant down-regulation of NOS2 (M1 macrophages), RORc (Th 17 cells), and CCR4 (associated with M1 macrophages) within those mice with low renal atrophy. The results suggest that under certain conditions, MSCs have a possible effect on the inflammatory environment present in RAS mice. Future studies will determine whether intervention prior to development of severe atrophy will increase therapeutic efficacy of MSC.

NLRP3 deficiency reduces renal atrophy in renovascular hypertension (HUM1P.306)

Renovascular hypertension (RVH) affects up to 7% of individuals over 65 years of age. We have previously demonstrated that induction of oxidative stress is an early event in the development of RVH that leads to development of inflammation and renal atrophy. NLRP3 is one of the most well-known sensors of oxidative stress. However, the role of NLRP3 in the development of RVH and subsequent end-organ damage is not well understood. We therefore sought to test the hypothesis that inhibition of NLRP3 activation protects the heart and the kidneys of mice subjected to RVH. In accordance with our previous observations, wild type (WT) mice subjected to RVH developed 26±6% of renal atrophy within 1 week following cuff placement that progressed to almost 100% by 4 weeks. In contrast, although NLRP3-/- mice (KO) subjected to RVH developed similar degree of atrophy to their age-matched WT in the first week (29 ± 17 vs. 39 ± 20), the atrophy did not progress when evaluated at 4 weeks (29 ± 13 vs. 78 ± 10, p=0.013). Histologic evaluation of renal cortex of KO mice showed no significant interstitial infiltration with CD3+ T cells or F4/80+ macrophages. In addition, KO mice developed no cardiac hypertrophy, no cardiac fibrosis, or aortic lesion despite similar elevation in systolic blood pressure to the WT mice. We propose that NLRP3 activation plays a critical role in the development of renal atrophy in mice subjected to RVH and represent a potential therapeutic target.

The stenotic kidney of Rag1 mice subjected to 2K1C hypertension is protected from atrophy (P3078)

Renal artery stenosis is a common finding in patients with cardiovascular disease. Recent studies have provided evidence that innate immunity plays a critical role in the development of chronic renal disease in renovascular hypertension. We have previously demonstrated that interstitial infiltration of lymphocytes is an early event in the development of renal atrophy in the 2K1C model of renovascular hypertension. We therefore sought to test the hypothesis that lymphocytes play a role in the development of progressive atrophy/fibrosis in this model. We subjected mice to renal artery stenosis through placement of a polytetrafluoroethylene cuff on the right renal artery. In accordance with our previous observations, wild type mice subjected to RAS developed renal atrophy within 2 weeks following placement of the cuff (70.5 +/- 11.9%). Chemokine expression in renal cortex of the stenotic kidney reflected predominantly a Th1 response (STAT1, STAT4, TBX21); CCL2, CCL17, CCL12, and TNF mRNA expression were also upregulated, but not IL-6 and IL-10. In striking contrast to wild type mice, Rag1 mice developed significantly less atrophy (23.1 +/- 10.4, p&lt;0.0037 vs wild type). Unlike wild type mice, histologic evaluation of renal cortex of Rag1 mice showed no significant interstitial infiltration with CD3+ T cells or F4/80+ macrophages. We propose that T cell-mediated inflammation plays a critical role in the development of renal atrophy in 2K1C mice.

Decidua mesenchymal stem cells migrated toward mammary tumors in vitro and in vivo affecting tumor growth and tumor development

Mesenchymal stem cells (MSCs) have affinity to tumor sites where they home, affecting their biology and growth. Previously, we have isolated mesenchymal cells from the decidua of the human placenta named as decidua-derived MSCs (DMSCs). The aims of the present study were to investigate the migration capacity of DMSCs in vitro, and in vivo in a preclinical model of mammary tumors induced by N-nitroso-N-methylurea (NMU). Additionally, we assessed the safety of DMSC administration in vivo and their effect on tumor growth. In vitro studies showed that DMSCs significantly migrate toward both, healthy human breast tissue and breast adenocarcinoma. Nevertheless, the effect on DMSC migration was significantly higher in the presence of tumor tissue. DMSCs also significantly migrated in vitro in the presence of NMU-mammary tumor homogenate when compared with control media alone. In vivo studies showed both migration and engraftment of DMSCs into NMU-induced tumors. Interestingly, DMSCs showed an inhibitory effect on the growth of primary tumors and in the development of new tumors. DMSCs did not affect the growth of secondary tumors, although secondary tumors appeared 2 weeks later, and the number of secondary tumors was lower in the DMSC-treated rats as compared with vehicle-treated rats. To our knowledge, this is the first report showing placental MSCs effect on tumor growth. In conclusion, DMSCs could serve as a therapeutic agent themselves and as a cellular vehicle of anticancer drugs.

Inflammation in areas of tubular atrophy in kidney allograft biopsies: a potent predictor of allograft failure

The Banff scoring schema provides a common ground to analyze kidney transplant biopsies. Interstitial inflammation (i) and tubulitis (t) in areas of viable tissue are features in scoring acute rejection, but are excluded in areas of tubular atrophy (TA). We studied inflammation and tubulitis in a cohort of kidney transplant recipients undergoing allograft biopsy for new-onset late graft dysfunction (N = 337). We found inflammation ('iatr') and tubulitis ('tatr') in regions of fibrosis and atrophy to be strongly correlated with each other (p < 0.0001). Moreover, iatr was strongly associated with death-censored graft failure when compared to recipients whose biopsies had no inflammation, even after adjusting for the presence of interstitial fibrosis (Hazard Ratio = 2.31, [1.10-4.83]; p = 0.0262) or TA (hazard ratio = 2.42, [1.16-5.08]; p = 0.191), serum creatinine at the time of biopsy, time to biopsy and i score. Further, these results did not qualitatively change after additional adjustments for C4d staining or donor specific antibody. Stepwise regression identified the most significant markers of graft failure which include iatr score. We propose that a more global assessment of inflammation in kidney allograft biopsies to include inflammation in atrophic areas may provide better prognostic information. Phenotypic characterization of these inflammatory cells and appropriate treatment may ameliorate late allograft failure.

Spontaneous lupus-like syndrome in HLA-DQ2 transgenic mice with a mixed genetic background

To investigate the role of HLA-DQ2 in the pathogenesis of associated immune disorders, we generated transgenic mice that expressed HLA-DQ2 in the absence of endogenous murine class II molecules (AE(0)DQ2). These AE(0)DQ2 mice with a mixed genetic background spontaneously developed skin lesions on their ears, whereas control AE(0)DQ6 genotype control mice (also with a mixed genetic background) did not. The skin lesions were characterized by deep subepidermal blistering with hydropic degeneration and lymphoid infiltration in the subepidermal area as determined by histopathology. Immunofluorescence analysis revealed thick band-like granular deposition of IgG, IgM, and a thin band of IgA deposition along the basement membrane. AE(0)DQ2 mice also developed significant and progressive hematuria and proteinuria as compared with the AE(0)DQ6 mice (p < 0.05). Histopathology showed immune complex deposits in the glomeruli of AE(0)DQ2 mice. Immunofluorescence analysis showed progressive mesangial and capillary wall deposition of IgA, IgM, IgG and C1q in the kidney. With electron microscopy, the deposits showed a 'fingerprint' substructure; and tubuloreticular structures were identified within endothelial cells. Conversely, these changes were not observed in AE(0)DQ6 mice. Serum anti-double stranded (ds)DNA IgM and IgG levels were also significantly elevated among AE(0)DQ2 mice compared with AE(0)DQ6 mice (p < 0.001). In conclusion, AE(0)DQ2 mice spontaneously develop an autoimmune lupus-like syndrome and are useful model for this disease. It remains to be determined whether genetic admixture played a role in the development of this systemic lupus erythematosus-like syndrome in HLA-DQ2 transgenic mice. Lupus (2010) 19, 815-829.

Pathological and clinical characterization of the 'troubled transplant': data from the DeKAF study

We are studying two cohorts of kidney transplant recipients, with the goal of defining specific clinicopathologic entities that cause late graft dysfunction: (1) prevalent patients with new onset late graft dysfunction (cross-sectional cohort); and (2) newly transplanted patients (prospective cohort). For the cross-sectional cohort (n = 440), mean time from transplant to biopsy was 7.5 +/- 6.1 years. Local pathology diagnoses included CAN (48%), CNI toxicity (30%), and perhaps surprisingly, acute rejection (cellular- or Ab-mediated) (23%). Actuarial rate of death-censored graft loss at 1 year postbiopsy was 17.7%; at 2 years, 29.8%. There was no difference in postbiopsy graft survival for recipients with versus without CAN (p = 0.9). Prospective cohort patients (n = 2427) developing graft dysfunction >3 months posttransplant undergo 'index' biopsy. The rate of index biopsy was 8.8% between 3 and 12 months, and 18.2% by 2 years. Mean time from transplant to index biopsy was 1.0 +/- 0.6 years. Local pathology diagnoses included CAN (27%), and acute rejection (39%). Intervention to halt late graft deterioration cannot be developed in the absence of meaningful diagnostic entities. We found CAN in late posttransplant biopsies to be of no prognostic value. The DeKAF study will provide broadly applicable diagnostic information to serve as the basis for future trials.

Histopathologic clusters differentiate subgroups within the nonspecific diagnoses of CAN or CR: preliminary data from the DeKAF study

The nonspecific diagnoses 'chronic rejection''CAN', or 'IF/TA' suggest neither identifiable pathophysiologic mechanisms nor possible treatments. As a first step to developing a more useful taxonomy for causes of new-onset late kidney allograft dysfunction, we used cluster analysis of individual Banff score components to define subgroups. In this multicenter study, eligibility included being transplanted prior to October 1, 2005, having a 'baseline' serum creatinine < or =2.0 mg/dL before January 1, 2006, and subsequently developing deterioration of graft function leading to a biopsy. Mean time from transplant to biopsy was 7.5 +/- 6.1 years. Of the 265 biopsies (all with blinded central pathology interpretation), 240 grouped into six large (n > 13) clusters. There were no major differences between clusters in recipient demographics. The actuarial postbiopsy graft survival varied by cluster (p = 0.002). CAN and CNI toxicity were common diagnoses in each cluster (and did not differentiate clusters). Similarly, C4d and presence of donor specific antibody were frequently observed across clusters. We conclude that for recipients with new-onset late graft dysfunction, cluster analysis of Banff scores distinguishes meaningful subgroups with differing outcomes.

Osteoblastoma del hueso ganchoso. A propósito de un caso

Se presenta el caso de un osteoblastoma recidivante del hueso ganchoso y se revisa el tratamiento de esta lesión. Paciente varón joven con dolor y tumefacción en el dorso de la mano de seis meses de evolución sin respuesta al tratamiento sintomático. A la exploración radiológica se apreció una tumoración lítica del hueso ganchoso, y la RM mostró una tumoración con edema. Por biopsia incisional se diagnóstico que se trataba de un osteoblastoma, por lo que fue intervenido para practicar curetaje intralesional con aporte de esponjosa de cresta ilíaca autóloga. A los seis meses se observó una recidiva local, por lo que fue reintervenido mediante resección en bloque, con resultado final satisfactorio.

Fatal embryo chondral damage associated with fluoroquinolones in eggs of threatened avian scavengers

Stabled livestock reared in housed conditions are often subjected to intensive treatments with veterinary drug, which residues may be present in livestock meat ingested by scavengers, but nothing is known about their presence in eggs of wild birds and their potential detrimental effects on breeding success. We searched for residues of veterinary drugs and other toxicants in infertile and embryonated unhatched eggs of griffon vultures (Gyps fulvus) and red kites (Milvus milvus), two threatened avian scavengers. Quinolones (ciprofloxacin and enrofloxacin) were found in most unhatched eggs of both scavenger species clearly associated with severe alterations in the development of embryo cartilage and bones that could preclude embryo movements and subsequently normal development, pre-hatch position and successful hatching. The detrimental effects on developing eggs of veterinary drugs from livestock operations may help to explain reduced breeding success of avian scavengers.

Inflammatory myofibroblastic tumour of the larynx

A case of inflammatory myofibroblastic tumour of the larynx in a 74-year old man is reported. The lesion presented as a polypoid tumour arising in the left true vocal fold. The patient died of non-tumour-related causes and the autopsy showed persistence of the laryngeal tumour. Multicentricity and distant metastases were not detected. The literature about this entity and its differential diagnosis is reviewed and briefly commented upon.

[A matter of heart--two examinations of the same heart with a sixty year interval]

The 20th of May 1869, Professor Emanuel Winge used a human heart as an exhibit at a meeting of The Medical Society in Christiania. This heart was later conserved and kept in the museum of the Institute of Pathology. Sixty years later, one of Winge's successors, Professor Francis Harbitz, used the very same heart, also at a meeting of The Medical Society. Harbitz had then confirmed Winge's hypothesis of 1869, that the endocarditis of this heart was due to a bacterial infection. This article contemplates the disparity between the "scientific gazes" of Winge and Harbitz, and why Harbitz was able to convert Winges hypothesis of 1869 into a scientific discovery in 1929.

The Banff 97 working classification of renal allograft pathology

BACKGROUND

Standardization of renal allograft biopsy interpretation is necessary to guide therapy and to establish an objective end point for clinical trials. This manuscript describes a classification, Banff 97, developed by investigators using the Banff Schema and the Collaborative Clinical Trials in Transplantation (CCTT) modification for diagnosis of renal allograft pathology.

METHODS

Banff 97 grew from an international consensus discussion begun at Banff and continued via the Internet. This schema developed from (a) analysis of data using the Banff classification, (b) publication of and experience with the CCTT modification, (c) international conferences, and (d) data from recent studies on impact of vasculitis on transplant outcome.

RESULTS

Semiquantitative lesion scoring continues to focus on tubulitis and arteritis but includes a minimum threshold for interstitial inflammation. Banff 97 defines "types" of acute/active rejection. Type I is tubulointerstitial rejection without arteritis. Type II is vascular rejection with intimal arteritis, and type III is severe rejection with transmural arterial changes. Biopsies with only mild inflammation are graded as "borderline/suspicious for rejection." Chronic/sclerosing allograft changes are graded based on severity of tubular atrophy and interstitial fibrosis. Antibody-mediated rejection, hyperacute or accelerated acute in presentation, is also categorized, as are other significant allograft findings.

CONCLUSIONS

The Banff 97 working classification refines earlier schemas and represents input from two classifications most widely used in clinical rejection trials and in clinical practice worldwide. Major changes include the following: rejection with vasculitis is separated from tubulointerstitial rejection; severe rejection requires transmural changes in arteries; "borderline" rejection can only be interpreted in a clinical context; antibody-mediated rejection is further defined, and lesion scoring focuses on most severely involved structures. Criteria for specimen adequacy have also been modified. Banff 97 represents a significant refinement of allograft assessment, developed via international consensus discussions.

Redox regulation of renal DNA synthesis, transforming growth factor-beta1 and collagen gene expression

Growth and injury represent recurrent and related themes in the study of progressive renal disease. We have previously demonstrated that a prooxidant diet, one deficient in antioxidants, selenium and vitamin E, induces renal enlargement, proteinuria, mild tubulointerstitial disease and diminished glomerular filtration rate (GFR). Our present study represents continued examination of these processes. We demonstrate that these diets increase thymidine incorporation into DNA and net DNA content in renal tissue, and induce expression of the mRNA for the proto-oncogene, c-myc, and the histone, H2b. We localize increased DNA synthesis as occurring mainly in the distal renal tubular epithelium. These deficient kidneys also exhibit interstitial expansion that parallels the pattern of DNA synthesis in that both processes are more prominent in the medulla than in the cortex. mRNAs for collagens I, III and IV in conjunction with transforming growth factor-beta1 (TGF-beta1) are up-regulated in the kidney in rats maintained on the deficient diet. In complementary in vitro studies, the exposure of rat kidney fibroblasts, NRK 49F cells, to noncytolytic doses of hydrogen peroxide, induces collagen III, collagen IV and TGF-beta1 mRNA. Induction of these genes is also observed in mesangial cells so exposed to noncytolytic doses of hydrogen peroxide. A final aspect of our study was the examination of renal generation of hydrogen peroxide and the profile of the hydrogen peroxide-degrading enzymes. Deficient kidneys exhibit increased mitochondrial generation of hydrogen peroxide independent of oxygen consumption but in conjunction with suppression of glutathione peroxidase mRNA and activity. Lipid peroxidation was increased twofold in the cortex and medulla of the deficient kidneys. Surprisingly, catalase activity, measured in the cortex and medulla, and whole kidney catalase mRNA were also reduced in rats maintained on the antioxidant deficient diet, effects that may further compromise the clearance of hydrogen peroxide. These changes in catalase represent an adverse response to this dietary deficiency, and may be relevant to decreased catalase activity described in chronic renal insufficiency. Thus, a chronic prooxidant state, with features that mimic those of clinical uremia, increases DNA synthesis of renal tubular epithelium, induces mRNA expression for collagens I, III and IV in conjunction with the mRNA for the fibrogenic cytokine, TGF-beta1. Oxidants also induce collagen III, collagen IV and TGF-beta1 mRNA in vitro.

[Polymer microparticles for right and left heart echocardiography and imaging myocardial perfusion after peripheral vein injection]

It is conceivable that a stable ultrasound contrast agent could be used for reproducible right and left heart echocardiography and myocardial visualization after intravenous injection. Microparticles from different polymers and preparation procedures were screened in six dogs leading to one superior agent with reproducible high quality echo contrast in doses of 1 mg/kg. This special agent is based on condensates of aspartic acid, ethanolamine and decanoic acid. Out of this material particles were formed with an average diameter of 2 micrometers. The easily suspendable particles were used for the following studies in a dose of 1 mg/kg intravenously in eight pigs. Maximal video intensity averaged 116 +/- 42 relative intensity units (IU) in the right, 137 +/- 42 IU in the left ventricle, 42 +/- 7 in the normally perfused and 11 +/- 2 in the hypoperfused myocardium after circumflex ligature. The area under the intensity curve was 1942 +/- 100 IUxs in the right, 2452 +/- 1291 IUxs in the left ventricle, 518 +/- 124 in the normally perfused and 202 +/- 94 in the hypoperfused myocardium after circumflex ligature. There was no change of heart rate, central arterial or pulmonary artery pressure during and after the injections. There was also no loss of echo intensity during the passage of contrast material through the heart due to systolic pressure. The described agent can be used for the opacification and ultrasonic visualization of the right and left heart as well as normally and hypoperfused myocardium without visible side-effects in animal studies.