At the end of December 2019, epidemic cases of pneumonia of unknown cause in Wuhan, China were reported to the World Health Organization (WHO). A novel species of coronavirus was identified as the causative agent and named SARS coronavirus type 2 (SARS-CoV-2) because its genome sequence was found to be similar to that of SARS coronavirus (SARS-CoV), which caused the outbreak of severe acute respiratory syndrome (SARS) from 2002 to 2003. The WHO has designated the official name of SARS-CoV-2 infection as coronavirus disease 2019 (COVID-19) and declared it a pandemic on March 11, 2020. As of this writing (March, 2022), there are about 480 million people who have been infected with SARS-CoV-2 and more than 6 million killed worldwide, and the pandemic is inflicting a huge negative impact on various aspects of human life. Six species of coronavirus, which cause human diseases, had been identified before the outbreak of COVID-19. Four of them cause the common cold, and the other two cause severe respiratory disease with high case fatality rates. In this paper, the possible origins and phylogenetic properties of these human coronaviruses are summarized, and the future of the COVID-19 pandemic will be speculated based on the characteristics of pre-existing human coronaviruses.

Acute myocardial infarction (AMI) is a major cause of morbidity and mortality worldwide. Primary percutaneous coronary intervention (PPCI) is the gold standard treatment for patients presenting with ST-segment elevation myocardial infarction (STEMI). PPCI reperfusion therapy has the potential to reduce infarct size, preserve the left ventricle ejection fraction (LVEF), prevent lethal complications, and improve prognosis. A significant proportion of STEMI patients, however, develop post-infarct heart failure despite optimal PPCI. One of the reasons for post-infarct heart failure is that reperfusion injury increases the infarct area after PPCI. This article reviews the current understanding and up-to-date evidence basis for therapeutic intervention of reperfusion injury. Specifically, the combination of myocardial ischemia secondary to acute coronary occlusion and reperfusion injury leads to further myocardial injury and cell death. Multiple treatment modalities have been shown to be cardioprotective and reduce reperfusion injury in experimental animal models. Recent clinical trials have assessed multiple cardioprotective strategies, including ischemic pre- and post-conditioning, pharmacologic therapies, and mechanical devices. While several therapies have been shown to reduce infarct size in animal models or proof-of-concept studies, many large-scale trial results have proven inconsistent and disappointing. To decrease the incidence of severe heart failure in patients and extend healthy life expectancy in an aging society, further development of prevention strategies for reperfusion injury is needed, including novel maneuvers, drugs, devices, and combinations of the three.

Objective: To determine whether tumor necrosis factor (TNF) blockade improves small airway obstruction in rheumatoid arthritis (RA) patients without apparent respiratory symptoms.

Methods: Pulmonary function tests were performed before and one year after TNF blockade therapy in 29 RA patients without apparent respiratory symptoms. As a control, pulmonary function was examined at a one-year interval in 27 RA patients with conventional disease-modifying antirheumatic drugs (DMARDs) alone. Small airway obstruction was diagnosed when one of maximal mid-expiratory flow rate (MMEF), forced expiratory flow at 50% (FEF50) or 75% (FEF75) of the vital capacity was decreased to less than 60%, 55%, or 45% of predicted values, respectively.

Results: Small airway obstruction was found in 62.5% of RA patients. No differences were found in age, sex, disease duration, or disease activities. TNF inhibitors dramatically reduced disease activities. However, TNF inhibitors failed to improve small airway obstructions but worsened them.

Conclusions: TNF blockade fails to improve small airway obstruction, suggesting that TNF-independent pathways play important roles in the development of small airway obstruction in RA.

Introduction: Embolus due to plaque rupture is a risk of cerebral infarction for carotid artery stenting (CAS). Female have been controversial as a risk factor for cardiovascular interventions in recent years. MMP-9 has been previously reported to be associated with acute ischemic stroke and to be a potential marker for arteriosclerosis.

Therefore, this paper aimed to investigate the gender difference of embolic complications for CAS using MMP-9.

Material and Methods: We analyzed 46 consecutive cases of CAS performed with distal balloon protection, including 34 males and 12 females. Serum levels of matrix metalloproteinase (MMP) -9 were measured before and after CAS. Embolic events were examined in Diffusion Weighted Imaging (DWI) on MRI the next day after CAS.

Results: 13 cases (28.3%) had DWI-positive findings after CAS, and these results showed a significant gender difference (female 58.3% vs. male 17.6%, p < 0.05). Pre-CAS MMP-9 was significantly higher in females than in males (661.7 vs. 428.1 ng/ml, p < 0.05).

Pre-CAS MMP-9 tended to be higher in DWI-positive cases than DWI-negative cases with no significant difference (676.9 vs. 415.0 ng/ml, p = 0.051).

Conclusion: High serum MMP-9 in female have correlation with DWI positive findings after CAS. We suggest that high serum MMP-9 have a risk of cerebral infarction for CAS. Considering the results, CAS should be carefully performed, especially in female.

Introduction: Inflammation-based prognostic scores (IBPSs) is suggested to be associated with prognosis in many carcinomas including oral squamous cell carcinoma (OSCC), but we are skeptical that each IBPS alone is a strong prognostic factor. We examined whether IBPSs are valid prognostic predictors in a retrospective cohort study of patients undergoing primary surgery for OSCC.

Methods: The study was performed in 287 patients with OSCC primarily treated by surgery from 2007 to 2019 at our center. The IBPSs examined were the neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), lymphocyte-monocyte ratio (LMR), prognostic index (PI), and modified Glasgow prognostic score (mGPS), evaluated by blood tests at the first visit and at the end of primary treatment.

Results: There was no significant difference in OS and DFS between the two groups based on the cutoffs for NLR, PLR and LMR at first visit. Similarly, a comparison in OS and DFS for cases with mGPS and PI scores of 0 and 1 + 2 at the first visit showed no significant difference. The relative (at the end of primary treatment/the first visit) NLR, PLR and LMR had no effect on death or events. Whereas, worsening of mGPS and of PI at the end of primary treatment were both significantly correlated with poor prognosis for death and events (both p < 0.001).

Conclusions: This study found that IBPSs were not effective as presurgical prognostic factors for patient with OSCC in our center. Further investigation and validation of indices and assessment methods are required to improve the impact of IBPS biomarkers on prognosis prediction and treatment choice in patients with OSCC.

In the diagnosis of malignant lymphoma (ML), lymphadenectomy specimens are separated as needed for histological diagnosis, flow cytometry, and various genetic analyses after determining the suitability of the specimens from gross findings. We investigated gross findings for cut surfaces of lymphadenectomy specimens. Of the 57 patients who underwent lymphadenectomies, 7 were diagnosed with reactive lymphoid hyperplasia (RLH), 19 with follicular lymphoma (FL), 20 with diffuse large B-cell lymphoma (DLBCL), and 11 with Hodgkin lymphoma (HL). The gross findings for fresh, unfixed lymph node specimens with the maximum cut surface were evaluated in terms of color homogeneity, unevenness of cut surface, aspect ratio, presence of internal nodules, and capsular disruption. After this evaluation, a histological diagnosis was performed. In a comparison of color homogeneity, significantly more cases in the ML group (30/50 [60.0%]) were homogeneous than in the RLH group (1/7 [14.2%]) (P = 0.039). Capsular disruption was not observed in the RLH group, whereas it was found in 42/50 (84.0%) cases in the ML group (P = 0.001). The internal nodules between the FL group (17/19 [89.5%]) and HL group (9/11 [81.8%]) occurred more frequently than those of the DLBCL group (11/20 [55.0%]) (P = 0.039). Moreover, the internal nodules tended to be smaller in FL and HL than in DLBCL (P = 0.007). The color homogeneity and capsular disruption findings were important in differentiating ML from RLH, and the presence and size of the internal nodules were important in differentiating the ML subtypes.

Purpose: This study examined respiratory and circulatory responses during low-intensity resistance exercise using a KAATSU device, which results in moderate blood flow restriction, in both healthy male adults and male patients with cardiovascular disease.

Methods: Healthy males (n = 10, 29.8 ± 7.0 years) and male patients in cardiac rehabilitation (n = 10, 76.9 ± 3.4 years) performed leg extensions (3 sets of 15 repetitions at low-intensity [20% of a 1-repetition maximum]) not using and using a KAATSU device. We measured expiratory gas and impedance cardiography before (baseline) and during exercise, as well as dyspnea and rate of perceived exertion (RPE) during knee extensor effort immediately after each set of repetitions.

Results: The patients were older than the healthy participants. At baseline, although heart rates and ventilatory equivalents did not differ between groups, oxygen uptake, carbon dioxide output, and left cardiac work index (LCWi) were lower in patients than in healthy participants. There were no GROUP × KAATSU interactions in terms of respiratory and circulatory responses during low-intensity resistance exercise. Dyspnea and RPE increased with exercise set repetitions and the KAATSU device augmented the RPE in both groups.

Conclusions: There were no patient-specific changes in respiratory and circulatory responses, dyspnea, and responses to knee extensor effort using the KAATSU device during low-intensity resistance exercise, despite patients being older than healthy participants and exhibiting a lower respiratory function and LCWi at baseline than them. These results suggest that low-intensity resistance exercise using a KAATSU device can be a safe and useful training method for cardiac rehabilitation.

Background: Infection is an important factor in the development of renal diseases. We investigated the relationship between infection trends and the disease trends in renal biopsies.

Methods: The frequency of renal biopsy diseases in our department over the past 25 years was plotted annually and monthly and compared with the trends of sentinel observation of infectious diseases.

Results: IgA nephropathy increased in a cycle of 3 to 7 years, but its peak gradually decreases. IgA nephropathy showed a weak correlation with group A hemolytic streptococcus and drug-resistant Pseudomonas aeruginosa. On the other hand, in Henoch-Schönlein purpura showed a significant positive correlation with the secular variation of MRSA (r = 0.57, p < 0.01), influenza (r = 0.46, p < 0.05), and genital herpes (r = 0.45, p < 0.05) and condyloma (r = 0.43, p < 0.05). The frequency of ANCA nephritis was significantly correlated with the infection trends of adenovirus pharyngoconjunctival fever (r = 0.48, p < 0.05), hand-foot-mouth disease (r = 0.48, p < 0.05), influenza (r = 0.41, p < 0.05). It also showed a weak correlation with the secular and seasonal trends of group A hemolytic streptococcus. Minimal change nephrotic syndrome increased in a cycle of 4-5 years, and significantly correlated with group A hemolytic streptococcus (r = 0.561, p < 0.01), and the seasonal variation was associated with mycoplasma pneumonia, infectious erythema. Focal segmental glomerulosclerosis showed a significant correlation with the infectious trend of drug-resistant Pseudomonas aeruginosa (r = 0.62, p < 0.01), MRSA (r = 0.53, p < 0.05), Roseola (r = 0.53, p < 0.01), whooping cough (r = 0.42, p < 0.05).

Conclusion: Renal diseases diagnosed by renal biopsy have cyclical variations associated with seasonal and secular variations in infectious disease epidemics.

Limb-sparing surgery is important treatment for soft tissue sarcoma, but resection of major muscles in the lower extremities causes motor and gait dysfunction. However, we have experienced limb-sparing patients who have had significant improvement in their ability to walk.

We present the case of a 52-year-old woman who had limb-sparing surgery for soft tissue sarcoma that removed hamstring muscles (biceps femoris, semimembranosus, and semitendinosus). After surgery, the patient suffered from gait disturbance but was able to stabilize her gait by wearing ankle-foot orthosis. The patient underwent knee flexor strength testing and gait analysis with and without the ankle-foot orthosis. The maximum torque of the knee flexor muscles was higher when the patient used the ankle-foot orthosis than without it. Gait analysis demonstrated improvement of knee flexion with the ankle-foot orthosis. The surface electromyogram showed that gastrocnemius activity was increased markedly by using the ankle-foot orthosis.

The ankle-foot orthosis not only fixed the ankle in place to avoid foot drop, but also allowed gastrocnemius to act effectively as a knee flexor muscle after hamstring resection. We recommend using an ankle-foot orthosis to improve the gait of patients who have undergone hamstring resection because of a soft tissue tumor, infection, or trauma.

The differential diagnoses of cystic epithelial masses in the sellar and parasellar regions, when based on clinical findings, imaging, and even histopathological examination, can be challenging. Considerable evidence in the literature supports the existence of a common ectodermal origin of selected sellar and suprasellar cysts, which may account for the overlap of radiological features and pathological transitional states observed among these lesions. Here, we describe a case of suprasellar Rathke's cleft cyst (RCC) mimicking a dermoid cyst, which after successful removal by endoscopic endonasal surgery (EES) by an experienced team of neurosurgeons and otolaryngologists achieved a good clinical outcome. A 30-year-old male was referred with chief complaints of left-sided loss of vision and headache. Magnetic resonance imaging findings indicated possible diagnoses as RCC, craniopharyngioma, or dermoid cyst because the cyst partly contained fluid with a lipid signal. The cyst was resected en-bloc with EES, and the histopathological diagnosis was RCC. RCCs may contain lipid components within the cyst, presumed to be cholesterin crystals due to chronic inflammation. In preoperative imaging of suprasellar cystic lesions, the presence of lipid components in the cyst may not indicate dermoid cyst, and care should be taken to differentiate it from RCC or craniopharyngioma.

We report three cases of methotrexate (MTX) -induced oral erosions and ulcers mimicking Stevens-Johnson syndrome (SJS) in older women with rheumatoid arthritis, although they did not had conjunctivitis. Furthermore, age, dehydration, and renal dysfunction could trigger adverse reactions of MTX, but one patient underwent dialysis, which is a contraindication for MTX. It is sometimes very difficult to differentiate the toxicity of MTX from SJS. Learning from the three cases, we propose that oral mucosal erosions without conjunctive mucosal inflammation, leukopenia, and thrombocytopenia differentiate MTX toxicity from SJS. Furthermore, our patients nearly recovered from myelosuppression within seven days and recovered from mucosal erosions characteristic of MTX toxicity within 14 days. These clinical courses could also be characteristic for MTX toxicity rather than SJS, although quick recovery does not happen in all cases. Therefore, physicians who prescribe MTX must accurately know MTX-induced adverse reactions to recognize them early. Furthermore, as seen in our patients, oral mucosal erosions occur often. Therefore, dermatologists or others who examine these symptoms should consider that mucosal erosions mimicking SJS could be an adverse reaction of MTX, regardless of whether or not SJS/toxic epidermal necrolysis is suspected.

A case in which HCC was diagnosed by an abdominal ultrasound examination conducted as part of a routine examination during pregnancy, and the patient then underwent cesarean section at 34 weeks' gestation and hepatectomy on the same day is presented.

A 37-year-old woman was found to be hepatitis B surface (HBs) antigen-positive at a routine checkup in the 12th week of pregnancy. She was diagnosed as an inactive hepatitis B virus (HBV) carrier and underwent abdominal ultrasound examination, which found no liver tumor. However, further abdominal ultrasound at 30 weeks' gestation showed an irregular tumor in the right lobe of the liver. Based on the ultrasound findings, the tumor was diagnosed as HCC. There was no evidence of metastases. A cesarean section followed by S5 partial hepatectomy was performed at 34 weeks 3 days of gestation. Ultrasound screening for HCC of pregnant women who are HBV carriers is very important for both mother and child.

Lipoma of the transverse colon with intussusception is a rare disease. We report our experience of a case of lipoma of the transverse colon with intussusception that was successfully treated by laparoscopic surgery. The case was an 81-year-old woman who consulted a local clinic with a chief complaint of abdominal pain. The patient was referred to our department because abdominal CT scan revealed intussusception of the transverse colon. A fist-sized abdominal mass was found along with corresponding tenderness in her left upper abdominal area to the periumbilical area. The patient was diagnosed with intussusception caused by transverse colon tumor and was planned to undergo surgery. Intussusception associated with tumor was observed in the middle of the transverse colon. However, since the mobility in the abdominal cavity was favorable, partial resection of the transverse colon was performed through small laparotomy. The resection specimen showed a semi pedunculated submucosal tumor 9 × 6 cm in size. Histopathologically, the patient was diagnosed with adipose tumor outgrown with mature adipocytes in varied sizes.

Background: Previous studies have shown that the hyperechogenic area of the substantia nigra (SN) does not change over the disease course in patients with Parkinson's disease (PD). However, longitudinal changes in SN echogenicity in patients with atypical parkinsonian syndrome (APS) remain unclear. We evaluated the change in SN hyperechogenic area over time in patients with PD and those with APS, including multiple system atrophy (MSA) and progressive supranuclear palsy (PSP).

Methods: A total of 22 patients with parkinsonism (14 PD, aged 71.0 ± 8.3 years; 8 APS (6 PSP and 2 MSA), aged 69.9 ± 9.6 years) who underwent transcranial sonography twice (≥6 months apart) were included in this study. Patients with insufficient temporal bone windows were excluded.

Results: The mean interval between examinations was 24.7 ± 15.3 months. No differences were detected in the hyperechogenic SN area between the first and second examinations (all patients, 0.17 ± 0.09 cm² vs. 0.17 ± 0.08 cm², p = 0.67; PD, 0.20 ± 0.08 cm² vs. 0.20 ± 0.08 cm², p = 0.45; APS, 0.11 ± 0.06 cm² vs. 0.12 ± 0.06 cm², p = 0.37, respectively). In both groups, there were no correlations between the hyperechogenic SN area and disease duration or severity.

Conclusion: The hyperechogenic SN area did not change over the disease course in PD or APS patients.