Evaluating a 3D Ultrasound Imaging Resolution of Single Transmitter/Receiver with Coding Mask by Extracting Phase Information.

We are currently investigating the ultrasound imaging of a sensor that consists of a randomized encoding mask attached to a single lead zirconate titanate (PZT) oscillator for a puncture microscope application. The proposed model was conducted using a finite element method (FEM) simulator. To increase the number of measurements required by a single element system that affects its resolution, the transducer was rotated at different angles. The image was constructed by solving a linear equation of the image model resulting in a poor quality. In a previous work, the phase information was extracted from the echo signal to improve the image quality. This study proposes a strategy by integrating the weighted frequency subbands compound and a super-resolution technique to enhance the resolution in range and lateral direction. The image performance with different methods was also evaluated using the experimental data. The results indicate that better image resolution and speckle suppression were obtained by applying the proposed method.

Pleuroperitoneal Communication and Ovarian Cancer Complicating Peritoneal Dialysis: A Case Report of a Patient with End-Stage Kidney Disease.

Peritoneal dialysis has been a widely accepted modality for treating end-stage kidney disease, but a regular dialysis schedule can be seriously disrupted by various comorbid conditions requiring surgical intervention. A 40-year-old woman who had been receiving peritoneal dialysis was sequentially but separately complicated by pleuroperitoneal communication and ovarian cancer. Despite the need for temporary interruption of her peritoneal dialysis schedule, it was successfully resumed after the relevant surgeries for each disease. Several concerns regarding overall postoperative dialytic management strategies, including how to deal with the peritoneal dialysis catheter during the postoperative period as well as how long peritoneal dialysis should be interrupted, which remain an unresolved issue in the field of nephrology, are also discussed.

Rapid method for electron tomographic reconstruction and three-dimensional modeling of the murine synapse using an automated fiducial marker-free system.

Electron tomography (ET) has recently afforded new insights into neuronal architecture. However, the tedious process of sample preparation, image acquisition, alignment, back projection, and additional segmentation process of ET repels beginners. We have tried Hitachi's commercial packages integrated with a Hitachi H-7650 TEM to examine the potential of using an automated fiducial-less approach for our own neuroscience research. Semi-thick sections (200-300 nm) were cut from blocks of fixed mouse (C57BL) cerebellum and prepared for ET. Sets of images were collected automatically as each section was tilted by 2° increments (±60°). "Virtual" image volumes were computationally reconstructed in three dimension (3D) with the EMIP software using either the commonly used "weighted back-projection" (WBP) method or "topography-based reconstruction" (TBR) algorithm for comparison. Computed tomograms using the TBR were more precisely reconstructed compared with the WBP method. Following reconstruction, the image volumes were imported into the 3D editing software A-View and segmented according to synaptic organization. The detailed synaptic components were revealed by very thin virtual image slices; 3D models of synapse structure could be constructed efficiently. Overall, this simplified system provided us with a graspable tool for pursuing ET studies in neuroscience.

Long-term biopersistence of tangled oxidized carbon nanotubes inside and outside macrophages in rat subcutaneous tissue.

Because of their mechanical strength, chemical stability, and low molecular weight, carbon nanotubes (CNTs) are attractive biological implant materials. Biomaterials are typically implanted into subcutaneous tissue or bone; however, the long-term biopersistence of CNTs in these tissues is unknown. Here, tangled oxidized multi-walled CNTs (t-ox-MWCNTs) were implanted into rat subcutaneous tissues and structural changes in the t-ox-MWCNTs located inside and outside of macrophages were studied for 2 years post-implantation. The majority of the large agglomerates were present in the intercellular space, maintained a layered structure, and did not undergo degradation. By contrast, small agglomerates were found inside macrophages, where they were gradually degraded in lysosomes. None of the rats displayed symptoms of cancer or severe inflammatory reactions such as necrosis. These results indicate that t-ox-MWCNTs have high biopersistence and do not evoke adverse events in rat subcutaneous tissue in vivo, demonstrating their potential utility as implantable biomaterials.

Fine visualization of filamentous structures in the bacterial cytoplasm.

A new method was established for fine visualization of bacterial subcelluar filamentous structures by freezing the bacterial cells to displace cytoplasmic matrix granules to the periphery. This method was successfully applied in immunoelectron microscopy and electron microscopic tomography, and should be applicable for further studies of bacterial architecture and nanotransportation.

Development and prevention of morphologic and ultrastructural changes in uremia-induced hyperplastic parathyroid gland.

The detailed ultrastructural changes of uremia-induced hyperplastic parathyroid gland and the effects of current medical treatments for secondary hyperparathyroidism were investigated. Marked enlargement of parathyroid cell with accumulation of mitochondria and lipids and a significant increase in the thickness of the pericapillary area with increased fibrosis and appearance of fibroblast like cells were noted in the hyperplastic gland caused by uremia and phosphate retention. These ultrastructural changes and biochemical findings indicating hyperparathyroidism were significantly suppressed by all of the treatment using phosphate restriction, calcitriol, and cinacalcet. The characteristic ultrastructural changes, including the morphologic evidence of nodule formation, were indicated.

The interaction of LFA-1 on mononuclear cells and ICAM-1 on tubular epithelial cells accelerates TGF-ß1-induced renal epithelial-mesenchymal transition.

The epithelial-mesenchymal transition (EMT) of renal epithelial cells (RTECs) has pivotal roles in the development of renal fibrosis. Although the interaction of lymphocyte function-associated antigen 1 (LFA-1) on leukocytes and its ligand, intracellular adhesion molecule 1 (ICAM-1), plays essential roles in most inflammatory reactions, its pathogenetic role in the EMT of RTECs remains to be clarified. In the present study, we investigated the effect of the interaction of LFA-1 on peripheral blood mononuclear cells (PBMCs) and ICAM-1 on HK-2 cells after stimulation with TGF-ß(1) on the EMT of RTECs. ICAM-1 was highly expressed in HK-2 cells. After TGF-ß(1) stimulation, the chemokines CCL3 and CXCL12 increased on HK-2 cells. After co-culture of PBMCs and HK-2 cells pre-stimulated with TGF-ß(1) (0.1 ng/ml) (HK-2-TGF-ß(1) (0.1)), the expression of the active form of LFA-1 increased on PBMCs; however, total LFA-1 expression did not change. The expression of the active form of LFA-1 on PBMCs did not increase after co-culture with not CCL3 but CXCL12 knockdown HK-2-TGF-ß(1) (0.1). The expression of epithelial cell junction markers (E-cadherin and occludin) further decreased and that of mesenchymal markers (vimentin and fibronectin) further increased in HK-2-TGF-ß(1) (0.1) after co-culture with PBMCs for 24 hrs (HK-2-TGF-ß(1) (0.1)-PBMCs). The phosphorylation of ERK 1/2 but not smad2 and smad3 increased in HK-2-TGF-ß(1) (0.1)-PBMCs. The snail and slug signaling did not increase HK-2-TGF-ß(1) (0.1)-PBMCs. Although the migration and invasion of HK-2 cells induced full EMT by a high dose (10.0 ng/ml) and long-term (72-96 hrs) TGF-ß(1) stimulation increased, that of HK-2-TGF-ß(1) (0.1)-PBMCs did not increase. These results suggested that HK-2 cells stimulated with TGF-ß(1) induced conformational activation of LFA-1 on PBMCs by increased CXCL12. Then, the direct interaction of LFA-1 on PBMCs and ICAM-1 on HK-2 cells activated ERK1/2 signaling to accelerate the part of EMT of HK-2 cells induced by TGF-ß(1).

A case of cervical cancer-related membranous nephropathy treated with radiation therapy.

Paraneoplastic nephropathy is a rare complication of malignant disease. We present a case of cervical cancer with biopsy-proven membranous nephropathy and associated nephrotic syndrome. Irradiation to the specific neoplasm site and to the metastatic paraaortic lymph node tissues lead to regression of the nephrotic syndrome without causing severe adverse events. Radiation therapy can be the first choice in the treatment of paraneoplastic nephrotic syndrome if the primary neoplasm is unresectable. Invasiveness of intervention and patient prognosis should be carefully deliberated in the management of the two diseases.

Development of a technique for introduction of an expressed complementary deoxyribonucleic acid into parathyroid cells by direct injection.

PTH is a major mediator of bone and mineral metabolism. However, physiological and pathological investigations of parathyroid cells (PTCs) have been limited because of the lack of available cell lines and because the organ is too small for detailed studies. Here, we describe a novel method for adenovirus-mediated cDNA transfer into PTCs, and we show the accuracy of the method in a rat model of uremia-induced secondary hyperparathyroidism. Rats underwent a 5/6-nephrectomy and were fed with a high-phosphate diet for 8 wk. The parathyroid glands were surgically exposed and adenoviruses containing LacZ or Ca-sensing receptor (CaSR) were directly injected into the glands under a zoom-stereo microscope. The parathyroid glands were analyzed for infection of adenovirus and immunohistochemically for expression of CaSR. The functional activity of exogenous CaSR in PTCs after this treatment was investigated based on changes of the calcium and PTH curve. A virus concentration of more than 10(9) plaque-forming units/ml was required for adequate infection of PTCs within 7 d after treatment. Marked increase of CaSR-positive PTCs by 2.39 +/- 0.72 times relative to control treatment, and significant colocalization of CaSR overexpression and virus labeling, were observed in glands after gene introduction. The calcium and PTH curve was shifted to the left from the basal position (set point, 1.10 +/- 0.09 to 0.76 +/- 0.12 mm; P < 0.0001), indicating successful introduction of a functionally active cDNA into the PTCs. This technique may facilitate an elucidation of biological effects through targeting and identification of specific features of PTCs, which may provide the basis for new clinical approaches.

[Case of lupus nephritis and enteritis associated with bilateral hydronephrosis].

A case of nephrotic syndrome associated with bilateral hydronephrosis in a 26-year-old female is reported. She was referred to our hospital because of persistent diarrhea, abdominal pain, and urinary disorders. On admission, ascites, intestinal edema, and bilateral hydronephrosis, were demonstrated by radiographic analysis. The findings of both physical and laboratory examinations showed evidence of systemic lupus erythematosus (SLE). In addition, diffuse proliferative lupus nephritis was consistently confirmed by a renal biopsy. Immediately after the initiation of steroid treatment, her abdominal symptoms disappeared followed by an improvement in the symptoms of intestinal edema, hydronephrosis, and the renal function. The relationship between ureterohydronephrosis and lupus cystitis, and the fact that lupus enteritis is often associated with lupus cystitis have been demonstrated by previous studies. Finally, the clinical manifestations observed in our case led us to consider the association of lupus enteritis and cystitis. We should bear in mind the possible association of several disorders, including nephrotic syndrome, enteritis, and hydronephrosis due to cystitis, in cases presenting with SLE.

Improvement of impaired calcium and skeletal homeostasis in vitamin D receptor knockout mice by a high dose of calcitriol and maxacalcitol.

Vitamin D plays a major role in mineral and skeletal homeostasis through interaction with the nuclear vitamin D receptor (VDR) of target cells. Recent reports have indicated that some cellular effects of vitamin D may occur via alternative signaling pathways, but concrete evidence for mineral homeostasis has not been shown in vivo. To investigate this issue, the actions of calcitriol (1,25D) and maxacalcitol (OCT), which were developed for treatment of uremia-induced secondary hyperparathyroidism, were analyzed in VDR knockout (VDR(-/-)) mice. The VDR(-/-) mice were fed a rescue diet immediately after weaning. 1,25D, OCT or a control solution was administered intraperitoneally to these mice three times a week for eight weeks. Biological markers and bone growth were measured and bone histomorphometric analysis of the calcein-labeled tibia was performed 24 h after the final administration. Significantly higher levels of serum Ca(2+) were observed in 1,25D- and OCT-treated mice, but the serum parathyroid hormone level was unchanged by both agents. Impaired bone growth, enlarged and distorted cartilaginous growth plates, morphological abnormalities of cancellous and cortical bones; a morbid osteoid increase, lack of calcein labeling, and thinning of cortical bone, were all significantly improved by 1,25D and OCT. The significance of these effects was confirmed by bone histomorphometrical analysis. Upregulation of the calbindin D(9k) mRNA expression level in the duodenum may explain these findings, since this protein is a major modulator of Ca transport in the small intestine. We conclude that 1,25D and OCT both at a high dose exert significant effects on Ca and skeletal homeostasis with the principal improvement of Ca status in VDR(-/-) mice, and some of these effects may occur through an alternative vitamin D signaling pathway.

Tonsillectomy and steroid pulse (TSP) therapy for patients with IgA nephropathy: a nationwide survey of TSP therapy in Japan and an analysis of the predictive factors for resistance to TSP therapy.

BACKGROUND: Tonsillectomy and steroid pulse (TSP) therapy was proposed as a curative treatment for IgA nephropathy by Hotta et al. (Am J Kidney Dis 38:736-742, 2001) based on data that about 50% of patients achieved clinical remission (CR) of urinary abnormalities. MATERIALS AND METHODS: As a primary survey, we sent a questionnaire and letter to 848 hospitals in Japan, each of which employed a Fellow of the Japanese Society of Nephrology between October and December of 2006, in order to gather information about the prevalence and efficacy of TSP therapy for patients with IgA nephropathy. As a secondary survey, we collected data from both low- and high-CR-rate groups to determine which factors predicted resistance to TSP therapy. RESULTS: A total of 2,746 patients received TSP therapy between 2000 and 2006. The CR rates, calculated by measuring urinary criteria 6 and 12 months after TSP therapy, were 32.0% (347/1,085) and 45.6% (452/991), respectively. Analysis of the 30 hospitals in which TSP therapy had been performed on at least ten patients revealed that the CR rates varied from below 10% to 100%. A secondary survey of ten hospitals revealed that, after correction of the CR rate from each hospital, patients could be categorized into three groups: those with a low CR rate (122 patients in four hospitals), a middle CR rate (78 patients in four hospitals), and a high CR rate (103 patients in two hospitals). The CR rate of all patients (N = 303) was 54.1%. A comparison of patient data between the low- and high-CR-rate groups showed a significant difference in age at onset (years; P = 0.05), amount of proteinuria (g/day; P = 0.02), total protein (g/dl; P = 0.02), pathological grade (P = 0.009), and prognostic score as described by Wakai et al. [Nephrol Dial Transplant 21:2800-2808, 2006, (P = 0.04)]. Univariate analysis revealed that there was a significant difference between non-CR and CR subgroups in duration from diagnosis until TSP therapy (6.9 +/- 6.8 versus 5.3 +/- 5.2 years; P = 0.02), amount of proteinuria (1.5 +/- 1.6 versus 0.8 +/- 0.8 g/day; P < 0.0001), serum creatinine (0.99 +/- 0.40 versus 0.87 +/- 0.34 mg/dl; P = 0.006), pathological grade (P = 0.0006), and Wakai et al.'s prognostic score (37.4 +/- 17.8 versus 28.1 +/- 15.1; P < 0.0001). A multivariate logistic analysis demonstrated that resistance to TSP therapy depends on age at onset, amount of proteinuria, hematuria grade, and pathological grade, and a score predicting resistance to TSP therapy could be derived by the formula: [(-0.0330) x (age) + (0.4772) x log (amount of proteinuria) - (0.0273) x (hematuria grade: 0, 1, 2, and 3) + (0.7604) x (pathological grade: 1, 2, 3, and 4) - 0.1894]. A receiver operating characteristic (ROC) curve showed that patients with a resistance score of greater than -0.02 easily resist TSP therapy (sensitivity 69%, specificity 75%, positive likelihood ratio 2.76). CONCLUSION: TSP therapy shows promise as a treatment that can bring about CR of urinary abnormalities, but unfortunately the average CR rate is about 50% at 1 year after treatment. Predictive factors for resistance to TSP therapy are age at onset, amount of proteinuria, hematuria grade, and pathological grade. The present study suggests that patients with either early-stage or mild to moderate IgA nephropathy easily achieve CR following TSP therapy, whereas patients with late-stage or severe disease are prone to TSP therapy resistance.

[Nephrotic syndrome associated with lung adenocarcinoma: report of an autopsy case].

A 73-year-old male with nephrotic syndrome was admitted to our hospital. He was empirically treated with prednisolone, which resulted in the alleviation of proteinuria, hypoproteinemia, and pleural effusion. Thereafter, a computed tomographic scan revealed a mass lesion in the right-lower lung field. Finally, the patient died of multiple organ failure induced by disseminated intravascular coagulation. Adenocarcinoma of the lung and membranous nephropathy (MN) were revealed by autopsy. MN tends to occur in the elderly, and is also occasionally associated with solid tumors, such as lung and gastrointestinal cancer. Therefore, a malignancy survey may be useful in the management of cases with nephrotic syndrome in which MN is pathologically defined. However, the initiation of empirical treatment without a pathological diagnosis is not an exceptional phenomenon. Physicians should, therefore, bear in mind the potential association of malignancy and immediately and carefully investigate the potential presence of a malignancy in elderly patients with a new onset of nephrotic syndrome.

[Case of Henoch-Schönlein purpura nephritis associated with IgA monoclonal gammopathy of undetermined significance].

We report the case of a 72-year-old man with nephritic syndrome and rapidly progressive renal failure due to Henoch-Schönlein purpura nephritis (HSPN). He was successfully treated with methylprednisolone pulse therapy, followed by oral prednisolone at the dose of 30 mg per day. He was also diagnosed by immunoelectrophoresis as IgA-lambda monoclonal gammopathy of undetermined significance (IgA-MGUS). Renal biopsy revealed the diffuse crescentic glomerulonephritis associated with mesangial deposition of IgA and C3. Since an immunofluorescence examination failed to show the deposition of lambda, the significance of IgA paraproteinemia on the HSPN was obscure in the present case. However, we must bear in mind the latent presence of IgA-MGUS in cases of HSPN.

Molecular and morphological approach of uremia-induced hyperplastic parathyroid gland following direct maxacalcitol injection.

The mechanisms explaining the clinical effects of direct maxacalcitol (OCT) injection into the hyperplastic parathyroid gland (PTG) in uremic patients with advanced secondary hyperparathyroidism (SHPT) were investigated by molecular and morphological examination. PTG of uremia-induced SHPT model rats were treated by a direct injection of OCT (DI-OCT) or vehicle (DI-vehicle). The changes in serum intact parathyroid hormone (intact-PTH) level, vitamin D and Ca-sensing receptor (VDR and CaSR, respectively) expression levels in PTG, and the calcium (Ca)-PTH response curve were examined; the induction of apoptosis in parathyroid cells (PTC) was also analyzed by the TUNEL method, DNA electrophoresis, and electron microscopic examination. Serum intact-PTH level following DI-OCT significantly decreased. Upregulation of both VDR and CaSR, a clear shift to the left downward in the Ca-PTH curve, and many apoptotic PTCs were observed in the DI-OCT-treated PTGs. However, these findings were not observed in the DI-vehicle-treated PTGs. Moreover, these effects were confirmed by the DI-OCT into one PTG and DI-vehicle alone into another PTG in the same rat. DI-OCT may introduce simultaneous VDR and CaSR upregulation and the regression of hyperplastic PTG, and these effects may provide a strategy for strongly suppressing PTH level in uremia-induced advanced SHPT.

Spironolactone suppresses peritubular capillary loss and prevents deoxycorticosterone acetate/salt-induced tubulointerstitial fibrosis.

We examined whether and how peritubular capillary (PTC) loss in the renal cortex contributes to the development of deoxycorticosterone acetate (DOCA)/salt-induced tubulointerstitial fibrosis. Uninephrectomized rats provided with 0.9% NaCl/0.3% KCl drinking solution ad libitum were divided into control, DOCA, and spironolactone groups, which were administered vehicle, DOCA alone, and DOCA plus spironolactone for 1 (initial phase) and 4 weeks (delayed phase), respectively. Exposure to DOCA initiated a sequence of events that initially involved reduced PTC density, followed by a delayed response that involved further reduced PTC density, development of tubulointerstitial fibrosis and hypertension, enhanced expression of transforming growth factor-beta1 and connective tissue growth factor, and impaired renal function. Concomitant with the reduced PTC density, the 2 hypoxia-responsive angiogenic factors (vascular endothelial growth factor and hypoxia-inducible factor-1alpha) and the antiangiogenic factor (thrombospondin-1) were upregulated in cortical tubular cells of the DOCA group during the 2 phases and only in the delayed phase, respectively. In the DOCA group, PTC endothelial cell apoptosis was enhanced during the 2 phases, and PTC endothelial cell proliferation was inhibited in the delayed phase. In accordance with upregulation of thrombospondin-1, p53 expression was enhanced in the DOCA group in the delayed phase. The initial and delayed effects of DOCA were blocked in the spironolactone group. We conclude that exposure to DOCA initially caused the reduced PTC density associated with enhanced apoptosis independent of thrombospondin-1, which induced tubulointerstitial fibrosis via p53-mediated thrombospondin-1 activation, and spironolactone conversely corrected the effects of DOCA to prevent fibrosis.

[Case of Henoch-Schönlein purpura nephritis complicated with essential mixed cryoglobulinemia].

We report a case of purpura nephritis complicated with essential mixed cryoglobulinemia. The patient was referred to our hospital because of a petechial rash on the lower extremities, microscopic hematuria, and progressive deterioration of renal function. The presumptive diagnosis of Henoch-Schönlein purpura (HSP) was made, and the patient was treated with prednisolone at the dose of 40 mg/day. However, there was a persistent purpuric skin rash. On the other hand, immunoelectrophoresis of the serum revealed the presence of IgA-lambda and polyclonal IgG in the cryoprecipitate. Granular staining for polyclonal rather than monoclonal IgA and C3 segmentally along the capillary walls demonstrated by immunofluorescence analysis of renal biopsy led to the diagnosis of purpura nephritis as the major mechanism of renal damage. After three sessions of cryofiltration, the patient's serum cryoglobulins decreased and the active rash finally settled, along with improvement of renal function. These observations suggest that the presence of cryoglobulinemia modulated the clinical course of HSP in our case. Therefore, the possibility of the latent presence of cryoglobulinemia in cases with HSP having an active rash refractory to steroid treatment should not be overlooked.

Cellular changes following direct vitamin D injection into the uraemia-induced hyperplastic parathyroid gland.

Background. Hyperplasia of the parathyroid gland (PTG) is associated not only with excessive secretion of parathyroid hormone (PTH) but also with changes in the parathyroid cell (PTC) characteristics (i.e. hyperproliferative activity and low contents of vitamin D and calcium-sensing receptors). The control of PTG hyperplasia is most important in the management of secondary hyperparathyroidism (SHPT), because the advanced stage of hyperplasia is considered irreversible. For the better control of the PTH level in dialysis patients with such advanced SHPT, percutaneous vitamin D injection therapy (PDIT) under ultrasonographic guidance was developed and various cellular changes caused by this treatment were also investigated using an animal model. Methods. The PTGs of Sprague-Dawley rats, which had been 5/6-nephrectomized and fed a high-phosphate diet, were treated with the direct injections of vitamin D agents, and cellular effects focusing the above-mentioned characters were investigated. Results. An adequacy of the direct injection technique into the rats' PTGs and the successful effects of this treatment in various biochemical parameters were confirmed. Such characteristics of advanced SHPT were simultaneously improved; in particular, it was confirmed that this treatment may be effective in controlling PTG hyperplasia by, at least in part, apoptosis-induced cell death. Conclusions. A locally high level of vitamin D strongly may suppress PTH secretion and regress hyperplasia, which is involved in the induction of apoptosis in PTCs, based on the simultaneous improvements of cellular characters of advanced SHPT. The PTH control introduced by this treatment successfully ameliorated osteitis fibrosa (high bone turnover rate).

Electron tomography of Nafion ionomer coated on Pt/carbon black in high utilization electrode for PEFCs.

To confirm the superiority of newly developed electrocatalyst layer (ECL) for polymer electrolyte fuel cells, three-dimensional dispersion states of Nafion ionomer in Pt/carbon black agglomerates were analyzed by electron tomography based on multiple TEM images taken at different tilt angles. Uniform distribution of the ionomer has been first observed, proving the high catalyst utilization in the new ECL distinctive from that of the conventional one.

Application of an automated specimen search system installed in a transmission electron microscope for the detection of caliciviruses in clinical specimens.

To evaluate the performance of an automated specimen search system in the detection of caliciviruses such as Norwalk-like viruses and Sapporo-like viruses, a suitable negative staining method was developed and the viruses were examined using the system installed in a transmission electron microscope (TEM). Clear images of the viruses were obtained by staining with 2% uranyl acetate at pH 4.0 as compared with 2% phosphotungstic acid staining at any pH. When the image parameter of 30+/-6 nm for the diameter of a single virus-like particle of 2% uranyl-acetate-stained Norwalk-like virus was set on the automated specimen search system, 95% of the virus-like particles that were counted by the conventional TEM technique were detected. The system was used to detect Norwalk-like viruses in five semipurified stool samples in which Norwalk-like viruses had already been detected by reverse transcription-polymerase chain reaction assay and conventional electron microscopy. The positive detection rate for Norwalk-like viruses, which had been counted by the conventional technique, ranged from 56.2 to 77.9% using this system. Our findings indicate that the automated specimen search system installed in a TEM is suitable for the detection of caliciviruses in semipurified stool samples. The system is useful for clinical diagnosis without the need for operator intervention.