Mutations in the nonstructural proteins of SARS-CoV-2 may contribute to adverse clinical outcome in patients with COVID-19.

Background: From late March through April 2021, we experienced a cluster of patients with COVID-19, named "Cluster K", with rapid severe illness compared with those who were infected before.

Methods: Patients with COVID-19 who were enrolled in this study were divided into two groups: 66 patients from November 2020 to March 2021 (group A) and 37 patients whose infection links were traced from Cluster K (group B). The primary outcome was mortality rate, and the secondary outcome was maximal oxygen flow rate as the severity of the disease.

Rare Clinical Course of Immunoglobulin G4-Related Inflammatory Abdominal Aortic Aneurysm with Multiple Rare Complications.

Immunoglobulin G4- (IgG4-) related inflammatory abdominal aortic aneurysm (AAA) has been recognized as a manifestation of IgG4-related disease (IgG4-RD). We experienced one patient with multiple consecutive manifestations before and after endovascular stent grafting for IgG4-related inflammatory AAA (IAAA). A 71-year-old man was diagnosed with IgG4-RD due to increased IgG4 serum concentration, typical findings of parotid gland biopsy, and periaortitis in another hospital 2 years and 7 months before visiting our hospital.

Solitary thymic metastasis of breast cancer 13 years after surgery.

A 59-year-old woman was noted to have an anterior mediastinal mass on computed tomography at a regular follow-up 13 years after initial surgery for left breast cancer. Magnetic resonance imaging showed an anterior mediastinal mass. A total thymectomy with excision of surrounding lymphoid tissue was performed.

Unruptured cystic artery pseudoaneurysm accompanied by Mirizzi syndrome: a report of a case.

Pseudoaneurysm of the cystic artery is a rare complication of cholecystitis. 34 cases have been reported from 1976 to 2012, searched on MEDLINE and most of the cases have presented with gastrointestinal bleeding. We report the third case of an unruptured pseudoaneurysm of the cystic artery associated with calculous cholecystitis.

Low-reflective wire-grid polarizers with absorptive interference overlayers.

Wire-grid (WG) polarizers with low reflectivity for visible light have been successfully developed. We theoretically consider the optical properties of simple sandwich structures of absorptive layer/transparent layer (gap layer)/high-reflective mirrors and found that it is possible to develop an antireflection (AR) coating owing to the interference along with the absorption in the absorptive layer. A wide variety of materials can be used for AR coatings by tuning the thicknesses of both the absorptive and the gap layers.

[Synchronous double invasive ductal carcinomas of the pancreas with multifocal branch duct intraductal papillary mucinous neoplasms of the pancreas].

A 52-year-old man with a history of distal gastrectomy for gastric cancer was admitted to our hospital because of jaundice. CT scan revealed double tumors in the pancreatic head and body concomitant with multicystic lesions of the pancreas. Total pancreatectomy with splenectomy and remnant gastrectomy was performed.

Granulocytic sarcoma of the gingiva: two case reports.

The intraoral occurrence of granulocytic sarcoma is extremely rare. This article describes 2 cases of granulocytic sarcoma of the gingiva in different clinical situations: one as a precursor to acute myeloid leukemia in a 50-year-old man and the other as a sign of blast crisis in a 59-year-old man with chronic myelomonocytic leukemia. Clinicians and oral surgeons should consider the possibility of tumorous lesion and systemic disease when an intractable ulcer is encountered in an oral cavity.

[ALK-negative primary gastric anaplastic large cell lymphoma].

A 56-year-old Japanese woman was admitted to our hospital with upper abdominal pain. Gastroendoscopy revealed a Borrmann III type tumor which was diagnosed from the biopsied specimen as an anaplastic large cell lymphoma (ALCL). CT scan revealed para-aortic and left-supra clavicular lymph node swelling, so her clinical stage was defined as IIIE according to the Ann Arbor classification.

Enhanced production of p24 Gag protein in HIV-1-infected rat cells fused with uninfected human cells.

Although many human molecules have been suggested to affect replication of human immunodeficiency virus type 1 (HIV-1), the distribution of such cofactors in human cell types is not well understood. Rat W31/D4R4 fibroblasts expressing human CD4 and CXCR4 receptors were infected with HIV-1. The provirus was integrated in the host genome, but only a limited amount of p24 Gag protein was produced in the cells and culture supernatants.

[A case of thrombotic thrombocytopenic purpura with systemic lupus erythematosus].

We described a case of thrombotic thrombocytopenic purpura (TTP) with systemic lupus erythematosus (SLE). A-60-year old woman was admitted to our hospital because of fever, disconsciousness, and general fatigue. 32 years ago, she was diagnosed as SLE with Raynaud's phenomenon, rash, photosensitivity, arthritis, lymphocytopenia, and ANA.

Surveillance program for early detection of hepatocellular carcinoma in Japan: results of specialized department of liver disease.

Objective: Surveillance of cirrhotic patients enables early detection of hepatocellular carcinoma (HCC) and possibly prolongs survival. The aim of this study was to explore whether early-stage HCC can be detected earlier at a specialized department of liver disease than in other institutions.

Methods: The study subjects were 574 patients with HCC.

Pseudomyxoma peritonei due to mucinous cystadenocarcinoma in situ of the urachus presenting as an inguinal hernia.

Pseudomyxoma peritonei is generally caused by appendiceal and ovarian tumors. Other primary sites have been rarely reported. We describe herein the second reported case of pseudomyxoma peritonei due to mucinous cystadenocarcinoma of the urachus.

Value of fusing PET plus CT images in hepatocellular carcinoma and combined hepatocellular and cholangiocarcinoma patients with extrahepatic metastases: preliminary findings.

Background/aims: This study aimed to evaluate the usefulness of (18)F-fluoro-2-deoxy-d-glucose positron emission tomography (PET) and PET plus computed tomography (CT) fusion images for the detection of extrahepatic metastases of hepatocellular carcinoma (HCC) and combined hepatocellular and cholangiocarcinoma (combined HCC/CC).

Methods: Twenty-one patients with HCC and combined HCC/CC were enrolled in the study from December 2004 to February 2005. In all patients, PET and CT of the chest to pelvis region were performed.

Pyoderma gangrenosum complicated with myelodysplastic syndrome followed by rapidly progressing pyothorax-associated lymphoma: a case report.

This report describes a patient with pyoderma gangrenosum (PG) complicated with myelodysplastic syndrome (MDS) followed by rapidly progressing pyothorax-associated lymphoma (PAL). A 74-year-old man was admitted with cutaneous gangrene associated with MDS. We diagnosed him as having PG, and high-dose oral prednisolone was started.

Unilateral renal cortical necrosis with contralateral hydronephrosis after surgery for uterus carcinoma.

Renal cortical necrosis (RCN) represents a rare cause of acute renal failure that is characterized by necrosis of the renal cortex with sparing of the medulla. Most previous RCN cases reported have been bilateral and have occurred in pregnancy. Unilateral RCN is a quite rare disorder.

Diagnostic clues for recurrent hepatocellular carcinoma: comparison of tumour markers and imaging studies.

Objective: To elucidate the usefulness of monitoring Lens culinaris agglutinin-reactive alpha-fetoprotein (AFP-L3) and des-gamma-carboxy prothrombin detected with a revised kit (DCP-R) as clues to the diagnosis of recurrent hepatocellular carcinoma (HCC).

Methods: A total of 57 patients with HCC were enrolled in the study. They were classified into two groups: group A comprised 27 patients in whom the diagnostic clue to recurrent HCC appeared before November 1997; these patients were monitored by ultrasonography, computed tomography (CT), AFP and des-gamma-carboxy prothrombin detected with a conventional kit (DCP-C).

[A case treated successfully with low-dose CDDP and 5-FU for the treatment of liver and para-aortic lymph node metastases and second metastasis to anterior mediastinum lymph nodes from gastric cancer after gastrectomy].

A 64-year-old-male had recurrent paraaortic lymph node and liver metastases eight months after total gastrectomy and with distal pancreatectomy and splenectomy for advanced gastric cancer. Combined chemotherapy with 5-FU and a low-dose of CDDP was effective and the both lesions disappeared. Thirteen months later, a second recurrence of anterior mediastinum lymph node metastases occurred.