Published papers

IgA nephropathy (IgAN) is the most common type of primary glomerulonephritis worldwide and leads to end-stage kidney disease. The proteinuria selectivity index (PSI) has been used to assess the prognosis in nephrotic syndrome, but its predictive value in patients with IgAN remains unclear. This single-center retrospective cohort study included patients who diagnosed with IgAN between March 2012 and March 2020. The PSI was calculated at the time of kidney biopsy. Patients were followed up from the time of kidney biopsy to kidney replacement therapy, death, transfer to another facility, or study completion. Ninety-four patients with a median age of 51 years were enrolled and divided according to the cutoff value of PSI determined by the receiver operating characteristic curve analysis into low-PSI (PSI <0.243, n = 39) and high-PSI groups (PSI ≥0.243, n = 55). The median follow-up duration was 70 months. Rates of remission of proteinuria and survival without a two-fold increase in serum creatinine were significantly better in the low-PSI group (both p < 0.01, log-rank test). Cox regression analysis showed that a low PSI was significantly associated with an increased likelihood of remission of proteinuria and hematuria (hazard ratio [HR] 1.96; 95% confidence interval [CI] 1.02-3.85 and HR 1.75; 95% CI 1.01-3.13, respectively), and a decreased risk of a two-fold increase in serum creatinine (HR 0.10; 95% CI 0.01-0.81). In conclusion, The PSI could have the potential to support the assessment of the prognosis of IgAN, in addition to established prognostic markers, by reflecting the overall glomerular permeability.

OBJECTIVE: There is a pressing need to understand the pathogenesis of histological findings and identify the biomarkers for predicting the histological severity in lupus nephritis (LN). This study aimed to identify the pathogenic signal pathway and elucidate urinary biomarkers for predicting the presence or severity of histological findings in LN. METHODS: Urine samples from patients with biopsy-proven active LN were screened for 1305 proteins using an aptamer-based proteomic assay. The diversity and expansion of individual renal histological features in LN were quantified to identify the urinary proteins associated with the histological findings found in each score. Candidate urinary proteins were validated in a validation cohort. Immunohistochemical staining of the renal tissues was performed to clarify the localisation of the candidate proteins. RESULTS: Cluster analysis extracted five histological subgroups according to their correlations with each histological finding in LN. Protein groups which correlated with each histological subgroup revealed a distinct pathogenesis in LN using pathway analyses. Enzyme-linked immunosorbent assay validation revealed that urinary calgranulin B (S100A9), MCP-1, and IGFBP-5 levels could specifically predict the presence and severity of active glomerular lesions, interstitial inflammation, and interstitial fibrosis, respectively. Immunohistochemical staining revealed the localisation of these proteins in each lesion. CONCLUSIONS: Renal histological findings may reflect the different pathogeneses involved in each lesion, and estimating the urinary calgranulin B, MCP-1, and IGFBP-5 levels may be useful in predicting the presence and severity of histological findings in LN.

Background: The mechanism for the development of thrombotic microangiopathy (TMA) during sepsis has only been partially elucidated. TMA is recognized as a disease caused by various factors, and may be involved in the emergence of organ damage in severe sepsis. Here we report a case of TMA that followed disseminated intravascular coagulation (DIC) due to severe infection in a patient with a reduced ADAMTS-13 activity level. Case presentation: An 86-year-old Japanese woman was admitted to our hospital because of low back pain and fever. A careful evaluation led to a diagnosis of acute obstructive pyelonephritis due to a ureteral stone. Proteus mirabilis was isolated from both blood and urine cultures. The patient developed systemic inflammatory response syndrome and DIC, and was treated with antibiotics and daily continuous hemodiafiltration. Although infection and the coagulation abnormalities due to DIC were successfully controlled, renal failure persisted and her consciousness level deteriorated progressively in association with severe thrombocytopenia and microangiopathic hemolytic anemia. We therefore suspected the presence of TMA and started plasma exchange, which resulted in an impressive improvement in consciousness as well as the laboratory abnormalities. The ADAMTS-13 activity was 44% and the patient tested negative for the ADAMTS-13 inhibitor prior to the initiation of plasma exchange. A renal biopsy was performed to determine the etiology of acute renal injury, which revealed findings that were interpreted to be compatible with the sequelae of TMA. The follow-up studies performed after the successful treatment of TMA showed that her plasma ADAMTS-13 activity level remained persistently low. It is surmised that septic DIC occurring in the presence of preexisting reduced ADAMTS-13 activity have led to the development of secondary TMA in the present case. Conclusion: The present case suggests that TMA can be superimposed on sepsis-induced DIC, and plasma exchange is expected to be beneficial in such situations. Clinicians should consider the possibility of secondary TMA that follows sepsis-induced DIC in certain indicative clinical settings.

Secondary polycythemia with increased production of erythropoietin (EPO) is known to occur in kidney diseases such as hydronephrosis and cystic disease, but the mechanism remains unclear. We report an 18-year-old female with isolated renal relapse of acute lymphoblastic leukemia accompanied by polycythemia. At the relapse, she presented with bilateral nephromegaly, mild renal dysfunction, and erythrocytosis with increased serum EPO levels up to 52.1 mIU/mL (9.1-32.8). Renal biopsy demonstrated diffuse lymphoblastic infiltration. The expression of hypoxia-inducible factor (HIF)-1 alpha, which is undetectable in normal kidney, was observed in the renal tubule epithelium compressed by lymphoblastic cells. These findings suggest that erythrocytosis was caused by renal ischemia due to leukemic infiltration. Polycythemia probably became apparent because of the lack of leukemic involvement of the bone marrow. With chemotherapy, the serum EPO level rapidly decreased to normal range accompanied by the normalization of kidney size and function. Renal leukemic infiltration may enhance EPO production, although not recognized in the majority of cases because of bone marrow involvement. C onclusion: Our case has clarified the mechanism of previously reported polycythemia associated with renal diseases as renal ischemia. Furthermore, we have added renal ischemia resulting from tumor infiltration to the list of causes of secondary polycythemia.

Histological evaluation of fibrosis after a liver biopsy is crucial for evaluating the pathology of patients with chronic liver disease. Previous studies have reported quantitative analyses of fibrosis using images of collagen-stained sections. However, analysis of these studies requires manual selection of the region of interest. In addition, the quantification of elastic fibers is not considered. The present study was conducted in order to measure both the collagen and elastic fiber area ratios using Elastica van Gieson-stained whole-slide images (WSIs) of liver biopsy specimens. High-resolution WSIs provide precise color classification, enabling accurate detection of even fine collagen and elastic fibers. To minimize the influence of pre-existing fibrous tissue, median area ratios of the collagen and elastic fibers were independently calculated from the image tiles of the WSIs. These median area ratios were highly concordant with area ratios after the pre-existing fibrous tissues were manually trimmed from the WSI. Further, these median area ratios were correlated with liver stiffness as measured by transient elastography (collagen: r=0.73 [P<0.01], elastic: r=0.53 [P<0.01]). Our approach to quantifying liver fibrosis will serve as an effective tool to evaluate liver diseases in routine practice.

Small cell esophageal carcinoma is a type of small cell neuroendocrine carcinoma (SCNEC). SCNEC follows an aggressive clinical course and has a poor prognosis despite multidisciplinary therapies. A standard therapeutic strategy, including surgery, radiation and first-/second-line chemotherapy, has not yet been established for SCNEC. We present a case of SCNEC of the esophagus. A 66-year-old male with SCNEC as extensive disease was treated with 60 mg/m(2) cisplatin on day 1 plus 60 mg/m(2) irinotecan on days 1,8 and 15 every 4 weeks (IP) with successful complete remission. After the sixth course of IP, increasing pro-gastrin-releasing peptide (ProGRP) and nonspecific enolase (NSE) levels and intense fluorodeoxyglucose (FDG) avidity in a lymph node around the celiac artery (SUVmax, 8.3) indicated a refractory relapse of the disease. The patient was treated with three courses of amrubicin (AMR, 35 mg/m(2)) administered intravenously for 3 consecutive days every 3 weeks as a second-line chemotherapy. The ProGRP and NSE levels returned to the normal range I month after the initiation of second-line chemotherapy. However, the ProGRP and NSE levels were elevated after the third course of AMR, and PET-CT revealed progressive disease with liver metastasis and extended lymph node metastasis. As the patient remained asymptomatic, paclitaxel (100 mg/m(2)) was started as third-line chemotherapy. Patients with SCNEC of the esophagus with extensive disease should be treated with aggressive chemotherapy rather than surgery or radiation monotherapy. In the present case, tumor markers such as ProGRP and NSE were predictive of relapse and PET-CT was used to detect relapse. Further research is required to identify and exploit promising agents for resistant SCNEC.

Although the majority of renal amyloidosis is caused by either acquired monoclonal immunoglobulin light-chain amyloidosis or reactive systemic amyloid A, some cases are caused by hereditary amyloidosis. Apolipoprotein A-II (apoAII) amyloidosis is a rare form of hereditary amyloidosis and cannot be diagnosed by a routine examination. Thus, the prevalence and etiology of apoAII amyloidosis are uncertain. In humans, a genetic mutation in the stop codon of apoAII is considered to be a cause of amyloid fibril formation. We report on a 68-year-old man who presented with proteinuria by apoAII amyloidosis without family history. His proteinuria gradually increased to 6 g/day within 1 year. A renal biopsy showed amyloid deposition in the glomeruli, however, acquired monoclonal immunoglobulin light-chain amyloidosis and reactive systemic amyloid A were ruled out. Immunohistochemistry revealed apoAII deposition in the glomeruli, but DNA sequencing did not identify any genetic mutation in the coding sequence of apoAII. Here, we report a case of apoAII amyloidosis without a genetic mutation in the coding sequence and discuss the etiology of apoAII amyloidosis.

Objective. Rho GTPase may be involved in human cancer invasion via the augmentation of cell motility and adhesion. We report on two point mutations of the D4-guanine diphosphate (GDP)-dissociation inhibitor (GDI) gene, one of the Rho-GDIs, which were found in a human leukemic cell line, Reh, and the mutated D4-GDI functions as an accelerator of leukemic cell invasion. Material and Methods. We investigated the altered activity of GDP dissociation by mutated (mt) D4-GDI and the functions of this mt and wild-type (wt) D4-GDI in invasion. The mice inoculated with wt or mt D4-GDI vector-transfected Raji cells were observed and examined pathologically. Adhesiveness and cell motility of wt or mt D4-GDI vector-transfected Raji cells were examined. Finally, it was examined whether Rho activation was changed by mutation of D4-GDI under the condition of Rho-GDI knockdown. Results. Two point mutations of the D4-GDI gene were found in Reh cells. The region of mutations is conserved among members of the Rho-GDI family at the amino acid level. D4-GDI with two mutations (V68L and V69A) functioned in a dominant negative manner in the inhibition of GDP dissociation from Rho. Severe combined immune-deficient mice inoculated with Raji cells developed hemiparalysis. The Raji cells were present in bone marrow and peripheral blood, and hepatic invasion was observed in 20% of the mice. Mice inoculated with wt D4-GDI vector-transfected Raji cells (wt 134) showed later paralysis and none developed hepatic invasion. Mice inoculated with mt D4-GDI-transfected Raji cells (mt D4) showed a 5-day reduction in the time to paraplegia and death. In addition, hepatic invasion was evident in 80% of mice transplanted with mt D4 cells. There were no differences in growth rates and amounts of guanine triphosphate (GTP)-bound Rho, cdc42, or Rac among all clones, however, GTP-bound Rho in mt D4 clone with short hairpin RNA (shRNA) vector for Rho-GDI knockdown was increased compared with wt D4 clone with shRNA vector for Rho-GDI knockdown. The mt D4 cells showed an augmentation of adhesiveness and cell motility. On the other hand, wt D4 cells showed a decreased ability of cell motility. Conclusion. These results suggest the mutated D4-GDI functions as a dominant negative molecule against the wt D4-GDI and accelerates invasion via regulation of cytoskeletal machinery. (c) 2008 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc.

BACKGROUND: Low birthweight infants have a reduced number of nephrons and are at high risk of chronic kidney disease. Preterm birth and/or intrauterine growth restriction (IUGR) may also affect peritubular capillary development, as has been shown in other organs. CASE-DIAGNOSIS/TREATMENT: We report two patients with a history of preterm birth and extremely low birthweight who showed polycythemia and renal capillary rarefaction. Patient 1 and 2, born at 25 weeks of gestation with a birthweight of 728 and 466 g, showed mild proteinuria at age 8 and 6 years, respectively. In addition to increasing proteinuria, hemoglobin levels became elevated towards adolescence and their serum erythropoietin (EPO) was high despite polycythemia. Light microscopic examination of renal biopsy specimens showed glomerular hypertrophy, focal segmental glomerulosclerosis, and only mild tubulointerstitial fibrosis. A decrease in the immunohistochemical staining of CD31 and CD34 endothelial cells in renal biopsy specimens was consistent with peritubular capillary rarefaction. CONCLUSIONS: Since kidney function was almost normal and fibrosis was not severe, we consider that the capillary rarefaction and polycythemia associated with elevated EPO levels were largely attributable to preterm birth and/or IUGR.

We recently established a high-speed, label-free, spectral imaging method based on stimulated Raman scattering (SRS). This method enables examination of cellular features within relatively short periods, thus enabling new imaging applications in pathology. Previously, we reported on label-free visualization of mouse tissue using SRS spectral microscopy combined with multivariate image analysis, but the feasibility of applying this approach to diseased tissues with diverse morphology and irregular chemical species has not been examined. We, therefore, assessed acetaminophen-induced liver injury to evaluate the potential use of Raman spectral microscopy for visualizing histopathologic specimens. Acetaminophen-overdosed mouse liver was prepared and the pathologic changes including centrilobular necrosis were confirmed. Multi-colored images were reconstructed through principal component analysis (PCA) of a multi-band SRS dataset, which provided rich information compared with a monochrome single-band SRS dataset. A wide view of the multi-colored principal component (PC) images showed the distribution of cellular constituents, which was similar to that observed by fat staining. In addition, different types of cells in liver parenchyma were also demonstrated. In conclusion, the combination of SRS spectral microscopy and PCA has the potential to reveal both the morphological and chemical features of specimens and therefore has potential utility in diagnostic pathology.

The patient was a 48-year-old Japanese woman diagnosed as having systemic lupus erythematosus at the age of 21 years when she presented with fever and an erythematous skin rash on her face and extremities. Prednisolonewas initiated at that time. Thirteen days before admission to our hospital, she was referred to us by her family physician. Upon admission, blood tests showed pancytopenia, hypocomplementemia, and renal dysfunction, as well as the presence of lupus anticoagulant. Urinalysis showed abundant proteinuria and heavy microscopic hematuria. After performing a renal biopsy, we initiated immunosuppressive therapy and an anticoagulant. On the 22nd hospital day, microangiopathic hemolytic anemia appeared with the progression of thrombocytopenia and renal failure, and the patient subsequently underwent ten sessions of plasma exchange. After the commencement of the plasma exchange, her general condition improved. Her renal dysfunction, however, continued to progress, and hemodialysis was started on the 36th hospital day. The light microscopy showed severe endo- And extra-capillary proliferative glomerulonephritis with abundant crescents, and massive thrombi in the capillary lumen of the glomeruli. The arterioles contained occlusive hyaline materials. An immunofluorescence study showed granular staining of immunoglobulins and complements along the glomerular capillary wall. An electron microscopy examination revealed the presence of electron-dense deposits in the subepithelial and intramembranous areas of the glomeruli, but subendo- Thelial deposits were absent. For cases with lupus nephritis (LN), immunosuppressive therapy based on corticosteroid remains the mainstay of treatment. However, immunosuppression alone may be insufficient when antiphos- pholipid antibody syndrome and thrombotic microangiopathy (TMA) are also present, and other treatment modalities including antiplatelet therapy, anticoagulation, and plasma exchange are likely to be necessary, as illustrated by the present case. Although the mechanism responsible for LN remains uncertain, we report a case of LN suggesting that TMA is associated with renal dysfunction.

When using different cameras and displays in the shot and display of one subject, different color images are often showed. To solve this problem, we have developed a color chart in which the constituent colors dyed with dyes are evenly distributed in the color space. We have also developed a tool that creates an International Color Consortium (ICC) profile from the captured image of this color chart. In this report, we will describe the color difference correction accuracy when our method is applied to actual stained pathological specimens taken with multiple whole-slide imaging (WSI). We confirmed color correction accuracy of Lab values in major parts such as the cell nucleus. The Lab value of the specimen itself measured by a spectrocolorimeter was compared with that of the captured image. As a result, the color difference ?E in H&E-stained cell nucleus was improved from 32.2 to 6.4 for Nanozoomer and from 13.5 to 7.2 for ultra-fast scanner (UFS) by our color correction. The results of the evaluations for other areas and other stain methods (PAS, EVG, MT, and PAM) were good. In the future, high-accuracy color correction of teacher data/evaluation data in AI diagnosis using pathological images will be important.

This study elucidated the etiology of C3 glomerulonephritis (C3GN) and non-C3GN with primary membranoproliferative glomerulonephritis (MPGN) using transmission electron microscopy (TEM) and periodic acid-methenamine silver stain (PAM-EM). Thirty-one primary MPGN cases were analyzed by TEM and PAM-EM to distinguish among MPGN I, MPGN II, MPGN III Burkholder subtype (MPGN IIIB), and Anders and Strife subtype (MPGN IIIA/S). Each case was also classified into C3GN or non-C3GN according to the standard C3GN definition using immunostaining. Four cases of MPGN II met C3 glomerulopathy; whereas, four cases of MPGN IIIB did not meet C3 glomerulopathy. Seven of 11 cases (64%) of MPGN I without GBM disruption and 7 of 12 cases (58%) of MPGN IIIA/S with GBM disruption met the non-C3GN criteria with significant immunoglobulins' deposition. Regardless of the C3GN or non-C3GN diagnosis, the deposits in primary MPGN I and MPGN IIIA/S exhibited ill-defined, amorphous, and foggy characteristics similar to those found in postinfectious GN but were different from immune complex (IC) deposits seen in MPGN IIIB. Not only C3GN but also non-C3GN was due to mechanisms other than IC deposition as found in postinfectious GN. Consequently, GBM disruption of MPGN IIIA/S was not due to IC deposition.

Objective: To evaluate the roles of circulating B cells in the pathogenic process of systemic lupus erythematosus (SLE) by measuring the expression of chemokines and their receptors. Methods: Peripheral-blood mononuclear cells were obtained from 17 active, 21 inactive SLE patients, and 13 healthy controls. The expression of CXCR4, CXCR5, and CCR7 on CD19+ B cells was determined by flow cytometry, serum concentration of CXCL12 was measured by enzyme-linked immunosorbent assay, and the chemotactic responsiveness of B cells toward CXCL12 was evaluated. B or plasma cells expressing CXCR4 in renal biopsy specimens were detected using immnofluorescent staining. Results: Flow cytometric analysis revealed that expression level of CXCR4 on circulating B cells was significantly higher in patients with active disease than in those with inactive disease or controls. Serum CXCL12 concentration was not different between these groups. In addition, the migratory ability of B cells toward CXCL12 was enhanced in active SLE patients. Finally, CXCR4-expressing B cells were more frequently observed in the renal biopsy specimens of lupus nephritis. Conclusion: Up-regulated CXCR4 expression on circulating B cells in active SLE may enhance their chemotactic response toward CXCL12, which may promote infiltration of these cells into inflamed renal tissue and contribute to the development of SLE.

BACKGROUND: Primary breast lymphoma (PBL) is a rare type of extranodal lymphoma, the diagnostic process for which presents significant challenges owing to an overlap in clinical and pathological features with those observed in triple-negative breast cancer (TNBC). However, the current literature reveals a paucity of information regarding the ramifications of potential diagnostic errors, particularly in the context of emergent therapeutic strategies for TNBC. Thus, we present a unique report of a case of PBL. CASE PRESENTATION: A 76-year-old female with no past medical or family history presented to the hospital with the chief complaint of a mass in the right breast. Two masses were palpated in the right breast: one 56 mm mass (No. 1) located at 10 o'clock, and a 21 mm large, elastic, hard mass (No. 2) at 4 o'clock. Needle biopsy was performed only on the larger 56 mm mass (No. 1). The results showed invasive carcinoma that was negative for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor-2. The preoperative diagnosis was right breast cancer (T3N0M0 Stage IIB) of the TNBC subtype. The patient refused the preoperative chemotherapy recommended by the treatment team; therefore, right breast mastectomy and sentinel lymph-node biopsy were performed instead. The histopathological diagnosis of the first mass was diffuse large B-cell lymphoma (DLBCL); that of the second mass (No. 2) was an invasive breast carcinoma of no special type. Postoperative treatment consisted of endocrine therapy (letrozole) for breast cancer, while the DLBCL was treated with chemotherapy and three courses of intrathecal chemotherapy. At the time of this report, the patient is still living, and neither tumor had recurred in the 2 years following surgery. CONCLUSIONS: On rare occasions, PBL can preoperatively mimic TNBC. While this case did not lead to serious consequences, because surgery was eventually selected as the first therapy, clinicians should be aware that the diagnosis of PBL is challenging using only a core-needle biopsy and can often be misdiagnosed as TNBC.

Heat shock proteins (HSPs) have been recognized as molecules that maintain cellular homeostasis during changes in the environment. Here we report that HSP90 functions not only in stress responses but also in certain aspects of cellular differentiation. We found that HSP90 showed remarkably high expression in undifferentiated human embryonal carcinoma (EC) cells, which Here subsequently dramatically down-regulated during in vitro cellular differentiation, following retinoic acid (RA) treatment, at the protein level. Surprisingly, heat shock treatment also triggered the clown-regulation of HSP90 within 48 h at the protein level. Furthermore, the heat treatment induced cellular differentiation into neural cells. This down-regulation of HSP90 by heat treatment was shifted to an up-regulation pattern after cellular differentiation in response to RA treatment. In order to clarify the functions of HSP90 in cellular differentiation, we conducted various experiments, including overexpression of HSP90 via gene transfer. We showed that the RA-induced differentiation of EC cells into a neural cell lineage was inhibited by overexpression of the HSP90 alpha or -beta isoform via the gene transfer method. On the other hand, the overexpression of HSP90 beta alone impaired cellular differentiation into trophoectoderm. These results show that down-regulation of HSP90 is a physiologically critical event in the differentiation of human EC cells and that specific HSP90 isoforms may be involved in differentiation into specific cell lineages.

A man who was an inactive hepatitis B virus (HBV) carrier with positive hepatitis B surface antigen (HBs antigen) and undetectable HBV-DNA under anti-viral treatment developed nephrotic syndrome at 52 years old, and a renal biopsy revealed advanced membranous nephropathy (MN) with focal cellular crescents, interstitial hemorrhaging, and peritubular capillaritis. Immunofluorescence studies demonstrated granular IgG deposition and HBs antigen-positivity along the capillaries. Glomeruli were negative for phospholipase A2 receptor 1. There were no clinical findings of systemic vasculitis. We considered MN combined with small-vessel vasculitis due to HBV infection. These results suggest that HBV-related kidney disease should be considered even in patients with an inactive HBV carrier status under treatment.

BACKGROUND: The histological subtype of lung adenocarcinoma is a major prognostic factor. We developed a new artificial intelligence model to classify lung adenocarcinoma images into seven histological subtypes and adopted the model for whole-slide images to investigate the relationship between the distribution of histological subtypes and clinicopathological factors. METHODS: Using histological subtype images, which are typical for pathologists, we trained and validated an artificial intelligence model. Then, the model was applied to whole-slide images of resected lung adenocarcinoma specimens from 147 cases. RESULT: The model achieved an accuracy of 99.7% in training sets and 90.4% in validation sets consisting of typical tiles of histological subtyping for pathologists. When the model was applied to whole-slide images, the predominant subtype according to the artificial intelligence model classification matched that determined by pathologists in 75.5% of cases. The predominant subtype and tumor grade (using the WHO fourth and fifth classifications) determined by the artificial intelligence model resulted in similar recurrence-free survival curves to those determined by pathologists. Furthermore, we stratified the recurrence-free survival curves for patients with different proportions of high-grade components (solid, micropapillary and cribriform) according to the physical distribution of the high-grade component. The results suggested that tumors with centrally located high-grade components had a higher malignant potential (P < 0.001 for 5-20% high-grade component). CONCLUSION: The new artificial intelligence model for histological subtyping of lung adenocarcinoma achieved high accuracy, and subtype quantification and subtype distribution analyses could be achieved. Artificial intelligence model therefore has potential for clinical application for both quantification and spatial analysis.