Evaluation of quantitative trait loci affecting intramuscular fat and reproductive traits in pigs using marker-assisted introgression.

We investigated the effects of previously identified quantitative trait loci (QTL) in an experimental backcross (BC) between Chinese Meishan pigs and commercial Duroc pigs. We performed marker-assisted introgression of two QTL for intramuscular fat (IMF) content (IMF population) and three QTL for reproductive traits (reproduction population) from a donor Meishan pig into a recipient Duroc pig. At the fourth BC generation of the IMF population and third BC generation of the reproduction population, carrier animals were selected for the production of animals homozygous for the QTL. Our previous studies have shown that the presence of a Meishan allele on the IMF QTL is associated with low IMF values, and the Meishan allele on the reproductive QTL is associated with large litters. In this study, the presence of a Duroc allele at the IMF QTL on SSC9 resulted in a 0.27% increase in IMF (additive effect = 0.27 ± 0.08), whereas the presence of a Meishan allele at the IMF QTL on SSC7 resulted in a 0.34% increase in IMF (additive effect = -0.34 ± 0.09). The presence of the Meishan allele at the IMF QTL on SSC7 thus had the opposite effect to our previous studies, that is, increased IMF. In the reproduction population, we observed no differences between the genotypes of the three QTL in regard to number of corpora lutea or litter size. Marker-assisted introgression at these QTL is thus unlikely to result in an associated increase in litter size. These results show that it is possible to introgress alleles from other breeds into a selection population using molecular markers; any unexpected results might be associated with the genetic background.

Sequence polymorphisms in porcine homologs of murine coat colour-related genes.

Herein, we report the variability among 57 porcine homologs of murine coat colour-related genes. We identified single nucleotide polymorphisms (SNPs) and insertions/deletions (InDels) within 44 expressed gene sequences by aligning eight pig complementary DNA (cDNA) samples. The sequence alignment revealed a total of 485 SNPs and 15 InDels. The polymorphisms were then validated by performing matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) with reference DNA samples obtained from 384 porcine individuals. Of the 384 individuals, three parents of the experimental F(2) family were included to detect polymorphisms between them for linkage mapping. We also genotyped previously reported polymorphisms of 12 genes, and one SNP each in three genes that were detected by performing a BLAST search of the Trace database. A total of 211 SNPs and three InDels were successfully genotyped from our porcine DNA panel. We detected SNPs in 33 of the 44 genes among the parents of an experimental F(2) family and then constructed a linkage map of the 33 genes for this family. The linkage assignment of each gene to the porcine chromosomes was consistent with the location of the BAC clone in the porcine genome and the corresponding gene sequence. We confirmed complete substitutions of EDNRB and MLPH in the Jinhua and Clawn miniature breeds, respectively. Furthermore, we identified polymorphic alleles exclusive to each pig group: 13 for Jinhua, two for Duroc, three for Meishan, four for the Japanese wild boar, one for the Clawn miniature pig and four for the Potbelly pig.

Clinicopathological features and prognosis in immunoglobulin light and heavy chain deposition disease.

BACKGROUND: There are three subtypes of monoclonal immunoglobulin deposition disease: light chain deposition disease (LCDD), light and heavy chain deposition disease (LHCDD), and heavy chain deposition disease (HCDD). Although it has been considered that LHCDD is a variant of LCDD, information on clinicopathological features and prognosis in LHCDD is presently limited. METHODS: We reviewed 5,443 renal biopsies, and evaluated clinicopathological features and outcomes in patients with LHCDD, in comparison with those in patients with LCDD and previously reported patients with HCDD. We also characterized paraprotein deposits in patients with LHCDD. RESULTS: We identified 6 patients with LHCDD, 6 patients with LCDD, and 1 patient with HCDD. The most common clinicopathological findings in patients with LHCDD were proteinuria, renal insufficiency, and nodular sclerosing glomerulopathy. Three patients had IgG-k deposits and 3 patients had IgG-l deposits. Heavy chain subclass analysis performed in 4 patients showed IgG3 deposits in all patients. Dual immunostaining revealed glomerular colocalization of light and heavy chains. In contrast with LCDD, glomerular C3 and C1q deposits were common findings in LHCDD and HCDD. All patients with LHCDD were treated with steroids and cytotoxic agents, but no effect on proteinuria was observed. Three patients developed end-stage renal disease requiring hemodialysis. The underlying hematological disorders in LHCDD and HCDD were milder than in LCDD. Early renal survival and overall patient survival in our patients appeared to be better in LHCDD than in LCDD. CONCLUSIONS: There are apparent differences in clinicopathological features and prognosis between LHCDD and LCDD. LHCDD is probably more similar to HCDD.

GATA-3 is upregulated in peripheral blood mononuclear cells from patients with minimal change nephrotic syndrome.

BACKGROUND: An imbalance of Th1 and Th2 cytokines has been reported in MCNS. Interleukin-13 (IL-13: Th2 cytokine) has been implicated in the pathogenesis of MCNS, but Th1/Th2 regulators such as T-bet (Th1-specific transcription factor) and GATA-3 (Th2-specific transcription factor) have not been examined. METHODS: We isolated PBMC from 25 patients with MCNS during nephrosis and remission phases, from 17 nephrotic patients with membranous nephropathy (MN), and from 25 healthy subjects. We measured mRNA expression levels of T-bet, GATA-3, Stat5A (regulator of Th2 priming), IFN-gamma (Th1 cytokine), IL-2 (Th1 cytokine and activator of Stat5), IL-4 (Th2 cytokine), and IL-13 in PBMC, using real-time RT-PCR. RESULTS: GATA-3, Stat5A, and IL-13 mRNA expression levels were higher in the nephrotic MCNS group compared to the others. IL-2 mRNA expression levels were higher in nephrotic patients with MCNS and MN than in MCNS patients in remission and healthy controls. There were no differences in mRNA expression levels of T-bet, IFN-gamma, and IL-4 between MCNS and MN patients and healthy controls. CONCLUSIONS: This study is the first to reveal increased mRNA expression levels of GATA-3 and Stat5A in PBMC from MCNS patients in nephrosis. This study also supports recent findings suggesting the role of IL-13 in the development of MCNS. A predominant Th2 type of T cell activation may be involved in the pathogenesis of MCNS.

Characteristics of proliferative glomerulo-nephritis with monoclonal IgG deposits associated with membranoproliferative features.

BACKGROUND: Proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) associated with membranoproliferative features is an extremely rare entity. Information on clinicopathological features and prognosis in this entity is limited. METHODS: We reviewed 5,443 renal biopsies processed at our department, and identified 4 patients with PGNMID associated with membranoproliferative features. We evaluated clinicopathological features and outcomes in these patients, and characterized paraprotein deposits by immunofluorescence studies. RESULTS: Three out of 4 patients had nephrotic syndrome with renal insufficiency at presentation. Cryoglobulin or monoclonal protein in serum and urine was not detected. Renal biopsy showed membranoproliferative features with or without nodular formation. Tubulointerstitial and vascular alterations were mild in three patients. All patients had glomerular IgG-kappa deposits. Heavy chain subclass analysis performed in 3 patients showed IgG3 deposits. Immunofluorescence studies using antibodies specific for gamma-heavy chain C(H)1, C(H)2, and C(H)3 domains and gamma3 hinge did not show any apparent deletion. Confocal microscopy revealed glomerular colocalization of light and heavy chains. On electron microscopy, granular deposits were predominantly mesangial and subendothelial. All patients were treated with steroids and cytotoxic agents, but no effect on proteinuria was observed. The renal outcome was progressive in all patients. Early death was observed in two elder patients. No patient had overt myeloma or lymphoma at presentation or over the course of follow-up (mean 43 months). CONCLUSIONS: Our study suggests a predominance of IgG3-kappa glomerular deposits of nondeleted whole immunoglobulin molecules in PGNMID associated with membranoproliferative features. The clinical outcome in patients with this entity appears to be poor.

Up-regulated expression of Toll-like receptors mRNAs in peripheral blood mononuclear cells from patients with systemic lupus erythematosus.

Recent studies in animal models for systemic lupus erythematosus (SLE) have shown that Toll-like receptors (TLR-7 and TLR-9) and interferon (IFN)-alpha are involved in the pathogenesis of murine lupus. Recent studies using flow cytometry have also shown increased expression of TLR-9 in peripheral blood mononuclear cells (PBMCs) from SLE patients. In this study, we performed quantitative real-time reverse transcription-polymerase chain reaction analyses of PBMCs from 21 SLE patients and 21 healthy subjects, to estimate TLR2, TLR3, TLR4, TLR5, TLR7, TLR8, TLR9, IFN-alpha and LY6E (a type I IFN-inducible gene) mRNA expression levels. Expression levels of TLR2, TLR7, TLR9, IFN-alpha and LY6E mRNAs in SLE patients were significantly higher than those in healthy controls. Expression levels of TLR7 and TLR9 mRNAs correlated with that of IFN-alpha mRNA in SLE patients. These results suggest that up-regulated expression of TLR7 and TLR9 mRNAs together with increased expression of IFN-alpha mRNA in PBMCs may also contribute to the pathogenesis of human lupus.

Renal amyloidosis associated with extracapillary glomerulonephritis and vasculitis in a patient with inflammatory bowel disease treated with infliximab.

A 70-year-old woman with an 11-year history of indeterminate inflammatory bowel disease developed rapidly progressive glomerulonephritis (RPGN) 3 months after the initiation of infliximab therapy. A renal biopsy showed Congo red-positive homogenous deposits in the mesangial area, glomerular capillary walls and arterial walls. Cellular and fibrocellular crescents were observed in 7 of 28 functioning glomeruli. There were findings of active tubulointerstitial nephritis and vasculitis of the small arteries. On electron microscopy, amyloid fibrils were observed in the deposits. Immunohistochemistry showed positive staining for amyloid A (AA) protein. After cessation of infliximab therapy, she was treated with methylprednisolone pulse therapy followed by oral prednisolone therapy. Thereafter, her RPGN was improved. This is a rare case of co-existent focal extracapillary glomerulonephritis with vasculitis and AA renal amyloidosis. Considering the temporal association of drug use with new onset of RPGN in our patient, we suggest a causal link between infliximab and RPGN due to extracapillary glomerulonephritis and vasculitis.

Successful treatment of post-MRSA infection glomerulonephritis with steroid therapy.

A 48-year-old man without underlying disease developed mediastinitis and was treated by mediastinal drainage. Methicillin-resistant Staphylococcus aureus (MRSA) was detected in a culture of the abscess material. He was treated with anti-MRSA antibiotics and the MRSA infection improved. Four weeks after the onset of MRSA infection, he developed rapidly progressive glomerulonephritis (RPGN) with nephrotic syndrome (NS). A renal biopsy showed endocapillary proliferative glomerulonephritis with IgA-predominant glomerular deposition. These clinicopathological findings were consistent with those in glomerulonephritis following MRSA infection (post-MRSA infection glomerulonephritis). The level of serum creatinine increased to 6.3 mg/dl, 7 weeks after the onset of RPGN. At that time, the eradication of MRSA infection was considered. He was given middle-dose steroid therapy. Thereafter, his RPGN with NS improved. MRSA infection did not recur. If the disease activity of post-MRSA infection glomerulonephritis persists after the disappearance of MRSA infection, the application of immunosuppressive therapy with steroids may be useful.

Predominant tubulointerstitial nephritis in a patient with systemic lupus erythematosus: phenotype of infiltrating cells.

A 63-year-old man with systemic lupus erythematosus developed tubular proteinuria. All subclasses of serum IgG increased, and the largest IgG subclass increase was IgG4. A renal biopsy showed lupus nephritis (Class II) with severe tubulointerstitial nephritis (so-called predominant tubulointerstitial lupus nephritis, an unusual form of lupus nephritis). Immunofluorescence microscopy revealed positive granular staining for IgG, C3 and C1q in the mesangium and peritubular interstitium, and along the tubular basement membranes (TBM). Electron microscopy also showed electron-dense deposits in the mesangium and TBM. Immunophenotyping of interstitial infiltrating cells disclosed a predominance of T cells. CD8-positive cytotoxic T cells infiltrated the peritubular interstitium, and some of these cells infiltrated the tubules. B cell-rich lymphoid follicles were also observed. IgG subclass analyses showed glomerular IgG1, IgG2 and IgG4 deposition, positive staining of IgG4 in the peritubular interstitium and along the TBM, and abundant IgG1-, IgG3- and IgG4-positive plasma cells in the interstitium. The patient responded well to moderate-dose steroid therapy. This is the first report of immunophenotyping of interstitial infiltrates in predominant tubulointerstitial lupus nephritis. The results suggest CD8-positive cytotoxic T cell-mediated tubular injury. Furthermore, immune complexes containing IgG4 might be one of etiologic factors.

Focal segmental glomerulosclerosis associated with polycythemia vera: report of a case and review of the literature.

A 69-year-old female with a 3-year history of polycythemia vera (PV) developed nephrotic syndrome. A renal biopsy showed focal and segmental glomerulosclerosis (FSGS). The patient was treated with prednisolone and myelosuppressive agents. Thereafter, parallel improvement of the two conditions was observed. After 4-year treatment, proteinuria disappeared. To our knowledge, there are five reported cases of FSGS associated with PV. Among them, three patients suffered from progressive azotemia. We suggest that steroid therapy with myelosuppressive agents can resolve the renal lesion in patients with PV.

Increased serum levels of S100A12 in patients with MPO-ANCA-associated glomerulonephritis.

BACKGROUND: Increased serum levels of S100A12, a proinflammatory protein secreted by activated neutrophils, have recently been shown in patients with active inflammatory diseases, such as rheumatoid arthritis and Kawasaki disease. In this study, we investigated serum levels of S100A 12 in patients with small-vessel vasculitis, myeloperoxidase anti-neutrophil cytoplasmic antibodies- (MPO-ANCA) associated pauci-immune glomerulonephritis. METHODS: Serum S100A12 concentrations were measured by a sandwich enzyme-linked immunosorbent assay (ELISA) in 46 patients with MPO-ANCA-associated glomerulonephritis and 29 healthy controls. We analyzed correlations between serum S100A12 levels and a clinical index of vasculitis activity, the Birmingham Vasculitis Activity Score (BVAS), various laboratory parameters, and pathological activity scores in the patients. We also analyzed changes of serum S100A12 levels in 10 patients after treatment. RESULTS: ELISA showed about 4-fold higher levels of serum S100A12 in patients with MPO-ANCA-associated glomerulonephritis than healthy controls. Serum S100A12 levels correlated with the BVAS scores, the peripheral white blood cell count, levels of serum C-reactive protein and creatinine, and pathological activity scores in the patients, but did not correlate with serum MPO-ANCA titers. Serum S100A12 levels after treatment decreased in all the 10 patients examined. CONCLUSION: We demonstrated that increased serum S100A12 levels correlate with clinical, laboratory and pathological parameters of disease activity in patients with MPO-ANCA-associated glomerulonephritis. Serum S100A12 level may be one of the useful markers of disease activity in MPO-ANCA-associated glomerulonephritis.

Analysis of the NPHP genes in two Japanese patients with suspected sporadic juvenile or adolescent nephronophthisis.

BACKGROUND: Mutations in 3 genes (NPHP1, NPHP3 and NPHP4) have been identified in patients with juvenile or adolescent nephronophthisis (NPHP) without extrarenal involvement, mainly in patients from western countries. In this study, we analyzed mutations in the NPHP genes of 2 Japanese patients with suspected sporadic juvenile or adolescent NPHP without extrarenal involvement. METHODS: A renal biopsy was performed in the 2 patients. Genomic DNA was prepared from peripheral blood mononuclear cells of the patients and their family members. The above NPHP genes were examined by deletion analysis or direct automated sequencing of polymerase chain reaction-amplified DNA products. RESULTS: Histological findings in the patients were compatible with those of NPHP. In 1 patient, we identified a novel deletion mutation including about half of exons of the NPHP1 gene. In another patient, there was no mutation in the NPHP genes examined. CONCLUSIONS: We found a novel NPHP1 deletion in 1 patient. To our knowledge, this is the second Japanese NPHP case in which genetic diagnosis was made.

Hemoperitoneum due to acute cytomegalovirus infection in a patient receiving peritoneal dialysis.

A 27-year-old man receiving continuous ambulatory peritoneal dialysis (CAPD) developed high-grade fever, dyspnea, and hemoperitoneum 32 months after the start of CAPD. A chest computed tomograph showed fine reticular shadows in the bilateral lower lung fields. Cytomegalovirus (CMV) antigenemia were detected, and immunoglobulin (Ig) M and IgG antibodies for CMV were also positive. The absolute counts of helper T cells (478/microL) and the ratio of helper T cells/suppressor T cells (0.25) decreased, despite no evidence of hematologic or immunologic diseases, including human immunodeficiency virus (HIV) or human T cell lymphoma virus-1 (HTLV-1) infection, or the use of immunosuppressive drugs. All symptoms, including hemoperitoneum and the ratio of helper T cells/suppressor T cells, improved gradually and spontaneously. Acute and primary cytomegalovirus (CMV) infection induced hemoperitoneum in a patient who was receiving CAPD.

Remission of the nephrotic syndrome in a patient with renal amyloidosis due to rheumatoid arthritis treated with prednisolone and methotrexate.

A 46-year-old woman developed nephrotic syndrome secondary to rheumatoid arthritis (RA). A renal biopsy showed deposition of amyloid fibrils in the subendothelial space of the glomerular capillary walls. After treatment with prednisolone (PSL, 40 mg/day), the levels of C-reactive protein (CRP) and serum amyloid A decreased to within normal limits for 2 weeks. However, the nephrotic syndrome persisted for 6 months after the therapy. To maintain the suppression of disease activity and to reduce PSL, methotrexate (5 mg/week) was added. The nephrotic syndrome resolved gradually, and the level of serum albumin returned to normal. Although renal prognosis of patients with nephrotic syndrome due to amyloidosis caused by RA has been considered poor, adequate and long-term treatment of RA with antiinflammatory drugs, including PSL and methotrexate, is useful for patients with secondary amyloidosis complicated by RA.

Endocapillary proliferative glomerulonephritis in a patient with parvovirus B19 infection.

A 45-year-old woman developed acute nephritic syndrome after erythema infectiosum. Laboratory data on admission showed decreased serum C3, C4, and CH50 levels and the presence of both immunoglobulin (Ig) M and IgG antibodies to human parvovirus B19 (HPV). A renal biopsy showed diffuse endocapillary proliferative glomerulonephritis. Immunofluorescence microscopy indicated 2+ granular staining for IgG, IgM, and C3 over the mesangial area and along glomerular capillary walls. HPV antigen was also detected in glomeruli by immunohistochemistry. Electron microscopy showed electron-dense deposits in the subendothelial space and the paramesangial area. These findings suggest that immune complex-type glomerulonephritis is caused by glomerular deposition of HPV antigen-antibody complexes in some patients with HPV infection.

Disappearance of nodular mesangial lesions in a patient with light chain nephropathy after long-term chemotherapy.

A 64-year-old man developed multiple myeloma (kappa light chain type), nephrotic syndrome, and renal insufficiency in 1993. A renal biopsy showed typical histological findings of light chain nephropathy: nodular glomerulosclerosis with deposition of kappa light chains in the mesangial area and subendothelial space of the glomerular capillary walls. Long-term intermittent MEVP chemotherapy (melphalan, 4 mg/d for 4 days; cyclophosphamide, 100 mg/d for 4 days; vincristine, 1 mg/d; prednisolone, 40 mg/d for 4 days) diminished proteinuria and improved renal function. In April 1999, a follow-up biopsy showed remarkable diminution of nodular lesions and disappearance of kappa light chain deposits. Although the prognosis of light chain nephropathy has been considered poor, long-term successful chemotherapy can clear light chain deposits and restore renal function.

Collagenofibrotic glomerulopathy: a systemic disease.

Collagenofibrotic glomerulopathy is a recently discovered entity that is characterized by massive accumulation of spiraled and frayed collagen fibrils in mesangial and subendothelial areas, and elevated serum levels of procollagen III peptide. We report the autopsy of a patient who received continuous ambulatory peritoneal dialysis (CAPD) therapy for 7 years. Autopsy disclosed that massive accumulation of peculiar collagen fibers was found not only in the kidney, but also in many organs including spleen, liver, myocardium, and thyroid gland. Although the possibility remains that CAPD for 7 years might change or aggravate the deposition of abnormal collagen, the current case suggests a possibility that collagenofibrotic glomerulopathy is a systemic disorder with abnormal metabolism of type III collagen.

Extensive intraglomerular thrombi of monoclonal IgM-kappa in a patient with malignant lymphoma.

We describe an 80-year-old man who developed malignant lymphoma (ML) complicated by extensive intraglomerular thrombi of immunoglobulin M (IgM)-kappa monoclonal immunoglobulin. The clinical picture was characterized by nephrotic syndrome and systemic lymphadenopathy. Laboratory examination showed mild anemia and a small amount of monoclonal IgM-kappa in the blood. The histopathologic findings and surface immunoglobulin analysis of the lymph node biopsy specimen were consistent with CD5-positive diffuse large B-cell (type, IgM-kappa) lymphoma. The subsequent renal biopsy showed a massive deposition of amorphous material in the glomerular capillary lumens, subendothelial areas, and mesangium. Nodular glomerulosclerosis was not found. An immunofluorescent study showed that the deposits consisted of IgM-kappa monoclonal immunoglobulin. Ultrastructurally, the deposits were composed of granular electron-dense material. Chemotherapy was effective for both the ML and nephrotic syndrome, and the patient's urine analysis results returned to normal. The histopathologic manifestations of this case are rare, and the pathogenesis of these glomerular lesions was obviously associated with ML.

A clinical analysis of 52 adult patients with hemophagocytic syndrome: the prognostic significance of the underlying diseases.

We retrospectively analyzed 52 adult patients with hemophagocytic syndrome (HPS). The underlying diseases were heterogeneous, including malignant lymphoma (lymphoma-associated hemophagocytic syndrome [LAHS]) in 26 patients, systemic lupus erythematosus in 3 patients, viral infections in 7 patients, and bacteria] or fungal infections in 6 patients. More than 83% of patients received prednisolone as an initial treatment. Multiple-agent chemotherapies (cyclophosphamide, doxorubicin, and vincristine) were administered to 96% of LAHS patients after a histopathological diagnosis of lymphoma. HPSs were controllable and remissions were achieved except for those patients with LAHS, fulminant Epstein-Barr virus-associated HPS, and an immunosuppressive state. Twenty-one (81%) of the LAHS patients had uncontrollable HPS and died of multiple organ failure and disseminated intravascular coagulation. The median survival time of LAHS patients was 83 days. In contrast, 3 (12%) of the other HPS patients died of multiple organ failure within 44 days.The clinical manifestations and the laboratory findings of LAHS and the other HPSs were too variable to establish the prognosis based only on the findings at the onset of HPS. The prognostic factors of adult HPS were found to be the underlying diseases, notably malignant lymphoma and infections, accompanied by the immunosuppressive state.

Crohn's disease associated with renal amyloidosis successfully treated with an elemental diet.

We report a case of Crohn's disease associated with nephrotic syndrome due to renal amyloidosis in a 21-year-old man in whom remission of both Crohn's disease and the nephrotic syndrome has been maintained with an elemental diet. The patient developed toxic megacolon and nephrotic syndrome due to renal amyloidosis. Intensive intravenous prednisolone therapy with total parenteral nutrition was dramatically effective in treating the toxic megacolon and inducing remission in Crohn's disease and afterward, remission of the nephrotic syndrome. Remission of both conditions has been maintained for more than 2 years with the elemental diet. To our knowledge, this is the first confirmed case of Crohn's disease complicated with renal amyloidosis in which only slight proteinuria (below 0.3 g/day) was shown with an elemental diet used for a long period.