Loop-Mediated Isothermal Amplification for Diagnosing SARS-CoV-2 Infection in Two School Children and a Neonate.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide and become a major public health problem. Although real-time reverse-transcription polymerase chain reaction (RT-PCR) is the gold standard for diagnosing coronavirus disease 2019 (COVID-19) and there are many reports discussing it, reports about loop-mediated isothermal amplification (LAMP) tests for SARS-CoV-2, especially in children, are limited. In this study, we present the results of LAMP test in three children with COVID-19 in a family cluster, and assess these results. The LAMP test results of these children showed a sensitivity and specificity of 63.6% and 100%, respectively, and that was comparable to the RT-PCR results. The results of both LAMP test and RT-PCR test using nasopharyngeal swab (NPS) were almost consistently similar in two school children throughout hospitalization except at the very early stages of infection. The preliminary results suggest that saliva samples would be less sensitive than NPS for LAMP testing in the late stages of infection, and that LAMP test would not provide accurate results in neonates.

The First Death in Japan Attributed to COVID-19: A Brief Report.

Our hospital encountered the first coronavirus disease 19 (COVID-19) pneumonia death in Japan. Moreover, we prevented nosocomial infection by taking appropriate infection control measures, without a negative pressure chamber. The patient was an 82-year-old woman who had no history of traveling to Wuhan or any direct contact with individuals who had been to Wuhan. Our patient had a seven-day history of fatigue, sudden fever, and hypoxemia. Chest computerized tomography images revealed peripheral ground-glass opacities in her lungs. A diagnostic COVID-19 reverse-transcription polymerase chain reaction (RT-PCR) analysis was positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The patient did not respond to any treatment and died 13 days after admission. The possibility of COVID-19 in a patient must always be considered, especially in the current scenario, to prevent nosocomial infection from spreading.

Downregulation of epidermal growth factor receptor family receptors and ligands in a mutant K-ras group of patients with colorectal cancer.

The present study investigated the expression profiles of the epidermal growth factor receptor (EGFR) family, which consists of four transmembrane tyrosine kinase receptors and their eight ligands, in 122 patients with colorectal cancer (CRC) using reverse transcription-quantitative polymerase chain reaction analysis. On comparison of the CRC primary tumor and matched adjacent normal mucosa (ANM) tissue samples, the mRNA expression levels of ErbB3, but not ErbB1, were significantly increased in CRC tissue samples, compared with those in the ANM tissues. The expression levels of the ligands exhibited opposing trends to their corresponding receptors, including EGF, BTC, AREG, EREG and HB­EGF, which were increased in the CRC tissues, whereas NRG1 and NGR2 were decreased in thee CRC tissues, compared with those in the AMN tissues. Subsequently, the present study investigated the frequency of K-ras mutations in the patients with CRC. The K­ras mutations were found to be present in 36.8% (45/122) of the cases, however, no correlation was observed between K­ras mutations and clinicopathological characteristics. In the CRC tissues, the expression levels of the EGFR family receptors and their ligands were determined in wild-type and mutant K-ras CRC cases. The expression levels of ErbB1, ErbB2, ErbB3, BTC, AREG, EREG, NRG1 and NRG2 were significantly decreased in the mutant K­ras cases, compared with those in the wild­type K­ras cases. These results suggested that the tumorigenesis of CRC with wild­type K­ras was mediated through, not only ErbB1, but also through the ErbB2 and ErbB3 pathways. Notably, although ErbB2 does not bind any ErbB ligands, ErbB2 may activate tumorigenesis via a heterodimer, rather than a homodimer. Therefore, the results of the present study suggest that the most effective strategy to target not only ErbB1, but also ErbB2 and ErbB3, is the use of monoclonal antibody treatment.

Clinicopathological significance and prognostic value of Wilms' tumor gene expression in colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is one of the most commonly diagnosed cancers, and novel effective treatments and diagnostic tools are urgently required. OBJECTIVE: The selection of appropriate targeting tumor-associated antigens (TAAs) is critical for immunotherapy. Therefore, we analyzed TAA expression levels and investigated their relationship with clinical factors in adjacent normal mucosa (ANM) and CRC tissue. METHODS: We obtained specimens of CRC primary tumors and matched ANM from 137 patients with CRC who underwent surgical resection. The mRNA levels of seven TAAs, Wilms' tumor gene (WT1), kinetochore associated-2 (KNTC2), cell division cycle associated-1 (CDCA1), M phase phosphoprotein-1 (MPHOSPH1), DEP domain-containing 1 (DEPDC1), 34-kDa translocase of the outer mitochondrial membrane (TOMM34) and ring finger protein-43 (RNF43), were analyzed using quantitative real-time reverse transcription-polymerase chain reaction, and their relationships with clinicopathological factors and the cell cycle were analyzed. RESULTS: The expression levels of all seven TAAs were significantly higher in CRC tissues than in ANM. Expression levels of WT1 in CRC tissues did not correlate with the cell cycle. Furthermore, WT1 expression in CRC tissues was significantly related to tumor progression, lymph node metastasis, distant metastasis and clinical stage. CONCLUSIONS: WT1 is a potential marker for prognosis and tumor progression in CRC.

Advanced gastric cancer showing long-term complete remission in response to S-1 monotherapy: two case reports.

We herein report two cases showing long-term complete remission (CR) in response to S-1 monotherapy. Case 1 was a 65-year-old male diagnosed with an advanced poorly differentiated adenocarcinoma of the stomach with paraaortic lymph node metastases, which disappeared after S-1 monotherapy. Subsequently a total gastrectomy was performed, and histological CR was evident. His progress is presently uneventful without recurrence 50 months after surgery. Case 2 was a 59-year-old female who underwent a total gastrectomy with a jejunal pouch. The resected tumor was a medullary type poorly differentiated adenocarcinoma infiltrating the serosa and involving the regional lymph nodes. One year after surgery, endoscopy revealed a recurrent tumor in the jejunal pouch. After the administration of S-1, this recurrent tumor completely disappeared, and she has since maintained CR for 39 months. These cases suggest that a subgroup of patients with advanced gastric cancer may attain CR with S-1 monotherapy.