Communication: Evaluation of the Humasis COVID-19 Antigen Rapid Diagnostic Test for the Diagnosis of SARS-CoV-2 Infection.

OBJECTIVE: We assessed the performance of the Humasis COVID-19 AgHS Test (Humasis, Korea), a novel antigen rapid diagnostic test (Ag-RDT) based on lateral flow immunoassay. METHODS: 85 SARS-CoV-2-positive and 155 SARS-CoV-2-negative nasopharyngeal swab specimens confirmed by rRT-PCR were tested using the Humasis and PBCheck Ag-RDTs. The analytical specificity of the Humasis Ag-RDT was evaluated using 27 strains of human respiratory pathogens. RESULTS: The overall sensitivity and specificity were 72.9% and 99.4% for the Humasis Ag-RDT and 64.7% and 100% for the PBCheck Ag-RDT, respectively. The sensitivity for specimens with Ct≤25 was 100% for both Ag-RDTs. The Humasis Ag-RDT showed no cross-reactivity with other respiratory pathogens. CONCLUSION: Our data suggests that the Humasis Ag-RDT can be a useful diagnostic tool for the detection of SARS-CoV-2 infection.

Cytomorphologic features of small cell carcinoma of lung in effusion fluid using a liquid-based cytology technique.

BACKGROUND: Liquid-based cytology (LBC) testing induces morphologic changes due to the use of specific fixatives and preparation techniques, and the cytologies of effusions determined in this manner differ morphologically from those of conventional cytopreparation (CCP) smear methods. We compared the cytologic features of pulmonary small cell carcinoma in effusion fluid using CCP and LBC preparations. METHODS: Fifty-three malignant effusion specimens from 36 patients with small cell carcinoma were examined, including 41 LBCs from 27 patients and 12 CCPs from 9 patients. RESULTS: LBC and CCP preparations preserved the typical features of small cell carcinoma, that is, nuclear molding, very high nuclear to cytoplasmic ratio and granular chromatin. The architectural patterns involved small cohesive clusters and chains with nuclear molding, tight three-dimensional clusters, or single cell dispersion were preserved in both preparations. Oval nuclei (83.3% vs 26.8%, P < .001) and a discernable rim of cytoplasm (66.7% vs 26.8%, P = .043) were more frequently identified in CCPs, whereas cellular degeneration and dry artifact were more frequent in LBC preparations (73.2% vs 8.3%, P < .001). LBC had a tendency to show frequent nuclear size variation (51.2% vs 25.0%) than CCP. CONCLUSION: LBC tends to show more degeneration and dry artifact with exaggerated irregular nuclear shape and nuclear size variation and scanty cytoplasm than CCP. Cytopathologists should be familiar with the cytomorphologic spectrum of this tumor in CCP and LBC prepared effusions.

Abundant expression of BMI1 in follicular lymphoma is associated with reduced overall survival.

Although generally indolent, follicular lymphoma (FL) sometimes pursues a more aggressive course leading to early death. B-cell-specific Mo-MLV insertion site-1 (BMI1) is a member of the polycomb group (PcG) proteins that confer stem cell properties through gene silencing. We used multi-channel immunofluorescence and automated image analysis to quantify BMI1 selectively in the nuclei of FL-derived B-cells in routine biopsy specimens. Applying this assay to 109 pretreatment FL biopsy samples demonstrates a significant association between abundant BMI1 and reduced overall survival (p = .001); the statistically significant association with mortality persists in a Cox proportional hazards model that includes Follicular Lymphoma International Prognostic Index (FLIPI) score, histological grade, and the presence of a component of diffuse large B-cell lymphoma in the biopsy sample. Ascertaining BMI1 over-expression may be useful in identifying patients who might benefit from novel therapies directed at reversing the chromatin-modifying functions of BMI1.

Heavy-ion injector based on an electron cyclotron ion source for the superconducting linear accelerator of the Rare Isotope Science Project.

The injector for the main driver linear accelerator of the Rare Isotope Science Project in Korea, has been developed to allow heavy ions up to uranium to be delivered to the inflight fragmentation system. The critical components of the injector are the superconducting electron cyclotron resonance (ECR) ion sources, the radio frequency quadrupole (RFQ), and matching systems for low and medium energy beams. We have built superconducting magnets for the ECR ion source, and a prototype with one segment of the RFQ structure, with the aim of developing a design that can satisfy our specifications, demonstrate stable operation, and prove results to compare the design simulation.

Development of superconducting magnets for RAON 28 GHz ECR ion source.

RAON, a 28 GHz electron cyclotron resonance ion source (ECR IS), was designed and tested as a Rare Isotope Science Project. It is expected that RAON would provide not only rare-isotope beams but also stable heavy ions ranging from protons to uranium. In order to obtain the steady heavy-ion beam required for ECR IS, we must use a 28 GHz microwave source as well as a high magnetic field. A superconducting magnet using a NbTi wire was designed and manufactured for producing the ECR IS and a test was conducted. In this paper, the design and fabrication of the superconducting magnet for the ECR IS are presented. Experimental results show that the quench current increases whenever quenching occurs, but it has not yet reached the designed current. The experiment is expected to reveal the ideal conditions required to reach the designed current.

Emittance study of a 28 GHz electron cyclotron resonance ion source for the Rare Isotope Science Project superconducting linear accelerator.

A 28 GHz electron cyclotron resonance (ECR) ion source is being developed for use as an injector for the superconducting linear accelerator of the Rare Isotope Science Project. Beam extraction from the ECR ion source has been simulated using the KOBRA3-INP software. The simulation software can calculate charged particle trajectories in three dimensional complex magnetic field structures, which in this case are formed by the arrangement of five superconducting magnets. In this study, the beam emittance is simulated to understand the effects of plasma potential, mass-to-charge ratio, and spatial distribution. The results of these simulations and their comparison to experimental results are presented in this paper.

Incidental diagnosis of vaginal schwannoma in a patient with thigh pain.

Schwannoma commonly arises from Schwann cells of the neural sheath, and is rare in the groin region. Here, we describe a vaginal schwannoma incidentally detected by magnetic resonance imaging (MRI) in a patient with thigh pain. A 43-year-old woman presented with thigh pain with burning and tingling sensations in the medial aspect of her left thigh. MRI revealed a mass lesion of heterogeneous intensity 5.2 × 5.7 cm in the left vaginal wall. The mass was resected and histology revealed schwannoma.

Squamous cell carcinoma arising in an ovarian mature cystic teratoma complicating pregnancy.

Mature cystic teratomas of the ovary (MCT) are usually observed in women of reproductive age with the most dreadful complication being malignant transformation which occurs in approximately 1% to 3% of MCTs. In this case report, we present a patient with squamous cell carcinoma which developed from a MCT during pregnancy. The patient was treated conservatively without adjuvant chemotherapy and was followed without evidence of disease for more than 60 months using conventional tools as well as positron emission tomography-computed tomography following the initial surgery. We report this case along with the review of literature.

Liver recurrence in early endometrial cancer with focal myometrial invasion.

Endometrial cancer is the most common malignancy of the female genital tract. The cancer spreads by direct extension, transtubal dissemination, lymphatic dissemination, and/or by hematogenous spread, usually results in lung metastasis, but may less commonly involve liver, brain, and bone. Here, we describe a patient with stage IA endometrial cancer who developed liver recurrence 17 months after surgery.

Cytological findings of the micropapillary variant of urothelial carcinoma: a comparison with typical high-grade urothelial carcinoma.

BACKGROUND: Micropapillary variant of urothelial carcinoma (MPUC) showed distinct pathologic features and aggressive behavior. The cytologic findings of MPUC are still indistinct. In this study, we evaluated the cytological findings of MPUC compared with those of high-grade urothelial carcinoma (HGUC). METHODS: The voided urine cytology of 8 cases of MPUC and 8 cases of HGUC was reviewed. Following cytological parameters were evaluated: cellularity, background, number of small, tight papillary clusters, small acinar structure, scattered single cells, cytoplasmic features, nuclear-to-cytoplasmic ratio, nuclear pleomorphism, nuclear membrane irregularity, hyperchromasia, chromatin pattern and nucleoli. RESULTS: Compared to that of HGUC, cytology of MPUC showed large numbers of small, tight papillary clusters, small acinar structure, few numbers of single cells, and hyperchromatic nuclei. Other parameters were similar between the two groups; both groups showed similar cellularity, dense or vacuolated cytoplasm, moderate to severe nuclear pleomorphism, irregular nuclear membrane, coarse granular chromatin, and small and prominent nucleoli. CONCLUSIONS: The urine cytology of MPUCs showed smaller and tighter papillary cell clusters, more small acinar structures, fewer numbers of scattered single cells, and more hyperchromatic nuclei than that of HGUC. These features can help to distinguish MPUC and HGUC and offer an early cytological diagnosis of MPUC.

Cytologic findings of clear cell adenocarcinoma of the urethra: a case report.

Clear cell adenocarcinoma of the urethra is a rare disease entity with an uncertain histogenesis. Here, we present a case of primary clear cell adenocarcinoma of the female urethra with its cytological findings. A 54-year-old woman presented with a painless gross hematuria lasting 3 months. On vaginal sonography, there was a sausage-like, elongated mass in the urethra, measuring 3.8×4.3 cm. The voided urine cytology revealed small clusters of rounded or papillary cells. The necrotic debris and inflammatory cells were present within some clusters of tumor cells. These tumor cells were enlarged and had abundant clear or granular cytoplasm with cytoplasmic vacuoles. The nucleus was granular and contained vesicular chromatin with prominent nucleoli. The hobnail cells and hyaline globules were also present as in a histologic section. The histologic findings were compatible with clear cell adenocarcinoma. The tumor showed distinctive cytological features. Cytologically, however, it is necessary to make a differential diagnosis from other adenocarcinoma or high-grade urothelial carcinoma.

Histopathology and TB-PCR kit analysis in differentiating the diagnosis of intestinal tuberculosis and Crohn's disease.

AIM: To compare the histopathologic features of intestinal tuberculosis (ITB) and Crohn's disease (CD) and to identify whether polymerase chain reaction for Mycobacterium tuberculosis (TB-PCR) would be helpful for differential diagnosis between ITB and CD. METHODS: We selected 97 patients with established diagnoses (55 cases of ITB and 42 cases of CD) who underwent colonoscopic biopsies. Microscopic features of ITB and CD were reviewed, and eight pathologic parameters were evaluated. Nine cases of acid fast bacilli culture-positive specimens and 10 normal colonic tissue specimens were evaluated as the positive and negative control of the TB-PCR test, respectively. PCR assays were done using two commercial kits: kit detected IS6110 and MPB64, and kit detected IS6110 only; a manual in-house PCR method was also performed on formalin-fixed, paraffin-embedded colonoscopic biopsy specimens. RESULTS: Statistically significant differences were noted between ITB and CD with regard histopathologic criteria: size of granulomas (P = 0.000), giant cells (P = 0.015), caseation necrosis (P = 0.003), confluent granulomas (P = 0.001), discrete granulomas (P = 0.000), and granulomas with lymphoid cuffs (P = 0.037). However, 29 cases (52.7%) of ITB showed less than five kinds of pathologic parameters, resulting in confusion with CD. The sensitivities and specificities of the TB-PCR test by kit , kit , and the in-house PCR method were 88.9% and 100%, 88.9% and 100%, and 66.7% and 100% in positive and negative controls, respectively. The PCR test done on endoscopic biopsy specimens of ITB and CD were significantly different with kit (P = 0.000) and kit (P = 0.000). The sensitivities and specificities of TB-PCR were 45.5% and 88.1%, 36.4% and 100%, and 5.8% and 100%, for kit and kit and in-house PCR method on endoscopic biopsy specimens. Among the 29 cases of histopathologically confusing CD, 10 cases assayed using kit and 6 cases assayed using kit were TB-PCR positive. A combination of histologic findings and TB-PCR testing led to an increase of diagnostic sensitivity and the increase (from 47.3% to 58.2) was statistically significant with kit (P = 0.000). CONCLUSION: The TB-PCR test combined with histopathologic factors appears to be a helpful technique in formulating the differential diagnosis of ITB and CD in endoscopic biopsy samples.

Comparison of gadoxetic acid-enhanced MR imaging versus four-phase multi-detector row computed tomography in assessing tumor regression after radiofrequency ablation in subjects with hepatocellular carcinomas.

PURPOSE: To assess the diagnostic value of gadoxetic acid-enhanced magnetic resonance (MR) imaging in follow-up of patients with hepatocellular carcinomas (HCCs) who were treated with radiofrequency (RF) ablation and to compare it with that of four-phase multi-detector row computed tomography (CT). MATERIALS AND METHODS: From July 2007 to May 2008, 36 patients (43 HCCs) were enrolled who were treated with RF ablation (tumor size, 20-47 mm; mean, 24.5 mm) and underwent gadoxetic acid-enhanced MR imaging and four-phase (precontrast, arterial, portal venous, and equilibrium) multidetector CT for follow-up. Two radiologists independently reviewed these images, and conspicuity of tumor margins and detection of residual or recurrent tumor were assessed on a five-point scale with receiver operating characteristic (ROC) curve analysis. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were evaluated. RESULTS: The mean conspicuity value of tumor margins was significantly higher on MR imaging than on multidetector CT (P < .001). The degree of differentiation between residual/recurrent tumor and hyperemia was significantly greater on MR imaging (P < .001). The mean area under the ROC curve was significantly higher with MR imaging (P = .015), as were sensitivity, specificity, PPV, NPV, and accuracy of detection rate (mean, 100%, 96.2%, 82.4%, 100%, and 96.7%, respectively, vs 41.7%, 56.8%, 13.5%, 85.7%, and 54.7% for multidetector CT). The interobserver agreement rate for MR imaging was higher (0.919) than for multidetector CT (0.672; P < .05). CONCLUSIONS: Diagnostic accuracy, conspicuity of tumor margins, and detection rate of residual or recurrent tumor were found to be better with gadoxetic acid-enhanced MR imaging than with four-phase multidetector CT.

PPARgamma agonist and angiotensin II receptor antagonist ameliorate renal tubulointerstitial fibrosis.

The peroxisome proliferator activated receptor (PPAR)gamma agonist is used as antidiabetic agent with antihyperglycemic and antihyperinsulinemic actions. Beyond these actions, antifibrotic effects have been reported. We examined antifibrotic effects of PPARgamma agonist and interaction with angiotensin receptor antagonist in the unilateral ureteral obstruction (UUO) model. After UUO, mice were divided to four groups: no treatment (CONT), pioglitazone treatment, L158809 treatment, and L158809+ pioglitazone treatment. On day 14, CONT mice showed severe fibrosis and all treated mice showed decreased fibrosis. The immunohistochmistry of PAI-1, F4/80 and p-Smad2 demonstrated that their expressions were increased in CONT group and decreased in the all treated groups compared to CONT. PAI-1 and p-Smad2 determined from Western blotting, among treated groups, was decreased compared to CONT group. The expression of TGF-beta1 from real time RT PCR showed markedly increased in the CONT group and decreased in all treated groups compared to CONT. These data suggest the pioglitazone inhibited tubulointerstitial fibrosis, however, the synergism between pioglitazone and L158809 is not clear. Considering decreased expression of PAI-1 and TGF-beta/Smad2 in the treated groups, PAI-1 and TGF-beta are likely linked to the decreased renal tubulointerstitial fibrosis. According to these results, the PPARgamma agonist might be used in the treatment of renal fibrotic disease.

Spontaneous liver rupture in a patient with peliosis hepatis: a case report.

Peliosis hepatis is a rare pathological entity and may cause fatal hepatic hemorrhage and liver failure. Here, we present a young male patient with aplastic anemia, who had received long-term treatment with oxymetholone. The patient suffered from sudden onset of intra-abdominal hemorrhage with profuse hemoperitoneum. The patient was treated successfully with a right hemihepatectomy and is in good health after 13 postoperative months. We suggest that peliosis hepatis be considered in patients with hepatic parenchymal hematoma, especially in patients under prolonged synthetic anabolic steroid medication. The possibility of a potentially life-threatening complication of massive intra-abdominal bleeding should also be considered.

Human immunodeficiency virus-negative plasmablastic lymphoma in Korea.

Plasmablastic lymphoma (PBL) is very rare, and predominantly occurs in Human immunodeficiency virus (HIV)-positive individuals. It shows a strong affinity for the oral cavity and for the Epstein-Barr virus (EBV) positive. We investigated the clinicopathologic characteristics of six cases of PBL in Koreans. All patients were HIV-negative and without underlying immunodeficiency. The age distribution was bimodal, and four patients were older than 60 years. Male predominance was observed with male to female ratio of 5:1. The organs primarily involved were the terminal ileum, stomach, oral cavity, tonsil, nasal cavity and meninges. The tumors were histologically typical of PBL. Three of them were composed of monomorphic large immunoblastic or plasmablastic cells, and classified as PBL of the oral mucosa type. Another three cases were classified as PBL with plasmacytic differentiation. Five cases revealed loss of B-cell antigens with CD138 or MUM1 substitution. CD10 was positive in two cases (PBLs of the oral mucosa type), and one of them unexpectedly expressed cytokeratin. EBV was detected in one case (PBL with plasmacytic differentiation). Four patients succumbed to PBL in a relatively short period of time. We suggest that PBL is not strongly associated HIV or EBV in Koreans, and that it shows a variable organ distribution without an oro-nasal predilection.

Hyalinizing spindle cell tumor with giant rosettes arising in the lung: report of a case with FUS-CREB3L2 fusion transcripts.

Hyalinizing spindle cell tumor with giant rosettes (HSCT) is a very uncommon mesenchymal tumor that has similar morphological and biological features to the low-grade fibromyxoid sarcoma (LGFMS). Lung involvement of HSCT is extremely rare, and only one case has been reported in the English-language literature. Reported herein is a case of primary pulmonary HSCT that had FUS-CREB3L2 fusion transcripts, a product of characteristic chromosomal abnormality t(7;16)(q33;p11) of HSCT and LGFMS. The patient was a 50-year-old woman who had a large solitary mass in the lung. Histologically, it was composed of bland spindle cells with variable cellularity deposited in a densely hyalinized stroma alternating with myxoid areas. Characteristic collagen rosettes were scattered in the cellular areas. Reverse transcription-polymerase chain reaction (RT-PCR) assay using formalin-fixed, paraffin-embedded tissue detected FUS-CREB3L2 fusion transcripts. Despite its bland morphology, it is known as low-grade sarcoma and its recognition in the lung would be helpful for accurate diagnosis and proper management of this rare tumor. RT-PCR for detection of FUS-CREB3L2 fusion transcripts is a useful method for differential diagnosis of primary pulmonary HSCT.

Mucinous adenocarcinoma arising from one retroperitoneal mature cystic teratoma in a postmenopausal woman.

Malignant degeneration of a retroperitoneal mature cystic teratoma to adenocarcinoma at postmenopausal age is extremely rare. A 72-year-old woman with mucinous adenocarcinoma arising from a retroperitoneal mature cystic teratoma is presented.

Comparison of transepidermal water loss, capacitance and pH values in the skin between intrinsic and extrinsic atopic dermatitis patients.

Atopic dermatitis (AD), with the prevalence rate of around 10 to 15%, is characterized by an intensely pruritic skin lesions with typical distribution and morphology. Recently, AD is divided into extrinsic type (ADe) and intrinsic type (ADi) according to the laboratory findings and associated diseases. ADe is well-known for high IgE level, positive response to food- or aero-allergens, whereas ADi has clinically similar skin lesions and distribution patterns of AD with normal serum IgE levels, negative in vitro test for environmental or food allergens and without associated atopic diseases. To instrumentally evaluate the differences of skin involvement and functions between ADi and ADe, we checked the transepidermal water loss (TEWL), capacitance and pH in both types of childhood AD and age-matched control. The proportion of ADi was around 20% in all AD patients (10/51). Our experiment suggested possible differences between ADi and ADe. Antecubital fossa is a famous involvement site of childhood type of AD, where both types of AD patients showed higher TEWL and decreased capacitance. ADe patients showed increased TEWL in all sites and lower hydration in 4 sites, whereas ADi patients showed no significant differences of TEWL and hydration in forehead, cheek, and back of leg.