Simulation of Deformation of Ni Twinned Nanocrystal Model by Molecular Dynamics

Molecular dynamics simulation of nickel crystal under uniaxial tensile and compressive deformation was performed for single nenocrystal model and twinned nanocrystal model composed of 1550 atoms using EAM (embedded atom method) potential with the object of investigating deformation induced phase tranformation (especially twin deformation). In the case of single nanocrystal model, the evolution and development of twin deformation, (111)[11(2)], is observed under compressive loading in [001] direction, whereas either slip or twin deformation is not recognized under tensile loading. In the case of twinned nanocrystal model, twin, (111)[11(2)], decreases and disappears under tensile loading, and develops under compressive loading, It is suggested from the difference of results between single nanocrystal model and twinned nanocrystal model that it is easy for twin to induce local deformation

Simultaneous hot and cold thyroid nodules: Which is malignant?

Physicians should be aware of the risk of malignancy in patients with toxic multinodular goiter. Radionuclide scan cannot be used to predict the malignant potential of thyroid nodules. A comprehensive evaluation of imaging studies is needed

Barium appendicitis

We have presented a case of barium appendicitis, which is a rare complication of barium enema studies. Barium sulfate is used widely for gastrointestinal radiographic studies and is associated with few complications. Clinicians need to be fully aware of this complication

A patient with human coronavirus NL63 falsely diagnosed with COVID-19; Lesson learned for the importance of definitive diagnosis

The gold standard for the diagnosis of coronavirus disease 2019 (COVID-19) is a nucleic acid detection test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which may occasionally reveal false-positive or false-negative results. Herein, we describe the case of a patient infected with human coronavirus NL63 (HCoV-NL63) who was falsely diagnosed with COVID-19 using the Ampdirect™ 2019-nCoV detection kit (Shimadzu Corporation, Japan) and admitted to a COVID-19 hospital ward. We suspected a cross-reaction between HCoV-NL63 and SARS-CoV-2; however, the reported genome sequences of HCoV-NL63 and N1/N2 primers for SARS-CoV-2 do not correspond. Thus, the patient was supposed to be false positive by the instrument, possibly due to contamination. Although the issue of a false-negative result has been the focus of much attention to prevent the spread of the disease, a false positive is fraught with problems as well. Physicians should recognize that unnecessary isolation violates human rights and a careful diagnosis is indispensable when the results of laboratory testing for COVID-19 are unclear, for instance if the duplicate PCR test is partially positive or the CT value is high

Angina Simultaneously Diagnosed with the Recurrence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) mainly affects young adults and can have a potential impact on social functioning. As this syndrome is associated with endothelial dysfunction, the heart can be damaged via ischemia due to endothelial damage. This might potentially lead to heart failure, which accounts for approximately 20% of deaths among patients with ME/CFS. While cardiac ischemia is thought be a pathophysiologically important manifestation of this syndrome, this is not yet reported. Herein, we present a case of a young female with newly diagnosed vasospastic or microvascular angina and concurrent exacerbation of ME/CFS severity. Her anginal symptoms, including exertional chest pain and transient chest discomfort, mimicked those of ME/CFS but were relieved after the administration of a calcium channel blocker. We emphasize the possibility of concurrent angina and exacerbation of ME/CFS and the importance of detecting cardiac ischemia to avoid unfavorable outcomes

Clinical Characteristics of Japanese Patients Who Visited a COVID-19 Aftercare Clinic for Post-Acute Sequelae of COVID-19/Long COVID

Introduction The long-term clinical course, prognosis, and optimal management of symptoms and conditions after the acute phase of coronavirus disease 2019 (COVID-19) remain to be elucidated. The purpose of this study was to clarify the characteristics of patients referred to a COVID-19 aftercare (CAC) clinic established at a tertiary academic hospital in Japan. Methods This study was a descriptive case series study. All patients who visited the CAC clinic between February 15 and September 17 in 2021 were included. Patients' background, chief complaints, and clinical courses after the onset of COVID-19 were described. Results A total of 87 Japanese patients (median age, 40.0 years; interquartile range [IQR], 26.5-53.0 years; 52.9% women) were referred to the CAC clinic. The median interval between the onset of COVID-19 and the visit to the clinic was 79.0 (IQR, 52.5-112.0) days. Referral sources were hospitals (36 patients), clinics (47 patients), a local healthcare center (3 patients), and other (1 patient). The most common chief complaint was general fatigue (50.4%) followed by dysosmia (28.7%), dysgeusia (26.4%), hair loss (18.4%), headache (17.2%), dyspnea (16.1%), and dyssomnia (13.1%). Respiratory symptoms were common in the early stages of the disease but were less common as the chief complaints when visiting the clinic. On the other hand, neurological, psychiatric, and extremity symptoms were predominant one month after the onset of COVID-19. Conclusions Regardless of the severity in the acute phase, patients visiting our CAC clinic suffered from a variety of symptoms. General physicians skilled in using a comprehensive approach would be optimal to see patients with such complex symptoms

胆嚢前癌性病変および胆嚢癌組織における腸上皮化生の検討

胆嚢粘膜の腸上皮化生が胆嚢癌の組織発生にどのように関与しているかを探る目的で,胆嚢前癌性病変および胆嚢癌組織内にみられた化生性変化の種類と頻度を組織学的に検討した.対象として腺腫8例,異型上皮7例,過形成性ポリープ20例,粘膜癌11例および進行癌37例の計83例を用いた.その結果,異型上皮では杯細胞,粘液腺および内分泌細胞が60～80%の頻度でみられ,また過形成性ポリープでも粘液腺,杯細胞,内分泌細胞およびパネート細胞がおのおの10～100%の頻度で認められた.しかし腺腫では杯細胞のみが25%にみられたにすぎなかった.また粘膜癌では杯細胞と内分泌細胞が22～36%で,進行癌では同様の細胞が8～16%で認められた.以上より,胆嚢粘膜の腸上皮化生は,種々の化生性変化を高率に伴う異型上皮や過形成性ポリープから癌化する場合に重要な役割を演じ,化生性変化を伴うことが少ない腺腫からの癌化にはあまり関与しないものと推定した.In order to study the relationship between mucosal metaplastic changes and cancer histogenesis in the gallbladder, precancerous lesions and carcinomas were investigated histologically for frequency and the variety of intestinal metaplasia in them. The materials included 8 cases of adenoma, 7 cases of dysplasia, 20 cases of hyperplastic polyp, 11 cases of mucosal carcinoma and 37 cases of advanced carcinoma. Goblet cells, mucous glands and endocrine cells were detected in 60-80% of cases with dysplasia and 10-100% of cases with hyperplastic polyp. However, adenoma only displayed goblet cells in 25% of cases. In cases with carcinoma, goblet cells and endocrine cells were present in 22-36% of mucosal carcinomas and 8-16% of advanced carcinomas, all of which were well differentiated adenocarcinomas. These results seem to indicate that intestinal metaplasia play an important role in malignant changes from dysplasia and hyperplastic polyp rather than adenoma