Significant role of host sialylated glycans in the infection and spread of severe acute respiratory syndrome coronavirus 2.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been transmitted across all over the world, in contrast to the limited epidemic of genetically- and virologically-related SARS-CoV. However, the molecular basis explaining the difference in the virological characteristics among SARS-CoV-2 and SARS-CoV has been poorly defined. Here we identified that host sialoglycans play a significant role in the efficient spread of SARS-CoV-2 infection, while this was not the case with SARS-CoV. SARS-CoV-2 infection was significantly inhibited by α2-6-linked sialic acid-containing compounds, but not by α2-3 analog, in VeroE6/TMPRSS2 cells. The α2-6-linked compound bound to SARS-CoV-2 spike S1 subunit to competitively inhibit SARS-CoV-2 attachment to cells. Enzymatic removal of cell surface sialic acids impaired the interaction between SARS-CoV-2 spike and angiotensin-converting enzyme 2 (ACE2), and suppressed the efficient spread of SARS-CoV-2 infection over time, in contrast to its least effect on SARS-CoV spread. Our study provides a novel molecular basis of SARS-CoV-2 infection which illustrates the distinctive characteristics from SARS-CoV.

The kinesin KIF4 mediates HBV/HDV entry through the regulation of surface NTCP localization and can be targeted by RXR agonists in vitro.

Intracellular transport via microtubule-based dynein and kinesin family motors plays a key role in viral reproduction and transmission. We show here that Kinesin Family Member 4 (KIF4) plays an important role in HBV/HDV infection. We intended to explore host factors impacting the HBV life cycle that can be therapeutically addressed using siRNA library transfection and HBV/NLuc (HBV/NL) reporter virus infection in HepG2-hNTCP cells. KIF4 silencing resulted in a 3-fold reduction in luciferase activity following HBV/NL infection. KIF4 knockdown suppressed both HBV and HDV infection. Transient KIF4 depletion reduced surface and raised intracellular NTCP (HBV/HDV entry receptor) levels, according to both cellular fractionation and immunofluorescence analysis (IF). Overexpression of wild-type KIF4 but not ATPase-null KIF4 mutant regained the surface localization of NTCP and significantly restored HBV permissiveness in these cells. IF revealed KIF4 and NTCP colocalization across microtubule filaments, and a co-immunoprecipitation study revealed that KIF4 interacts with NTCP. KIF4 expression is regulated by FOXM1. Interestingly, we discovered that RXR agonists (Bexarotene, and Alitretinoin) down-regulated KIF4 expression via FOXM1-mediated suppression, resulting in a substantial decrease in HBV-Pre-S1 protein attachment to HepG2-hNTCP cell surface and subsequent HBV infection in both HepG2-hNTCP and primary human hepatocyte (PXB) (Bexarotene, IC50 1.89 ± 0.98 µM) cultures. Overall, our findings show that human KIF4 is a critical regulator of NTCP surface transport and localization, which is required for NTCP to function as a receptor for HBV/HDV entry. Furthermore, small molecules that suppress or alleviate KIF4 expression would be potential antiviral candidates targeting HBV and HDV entry.

Patient Preference for Surgical Methods for Ipsilateral Breast Tumor Recurrence.

BACKGROUND: Mastectomy has been the standard surgical treatment for ipsilateral breast tumor recurrence (IBTR). Recently, there has been growing interest in repeat breast-conserving surgery (rBCS) for IBTR among breast surgeons; however, there is currently little information regarding patient preferences for surgical procedure for IBTR. The purpose of this study was to evaluate preference for surgical procedure (mastectomy vs. rBCS) among breast cancer patients who had undergone salvage surgery for IBTR. METHODS: Overall, 100 breast cancer patients who had undergone salvage surgery for IBTR were asked about their preferred surgical methods for IBTR and the reason. The association of patient preference and the reasons related to various clinical and pathological factors were assessed. RESULTS: Of the 100 respondents, only 11 patients (11%) preferred rBCS. Patients who had undergone rBCS and radiotherapy for IBTR were significantly more likely to prefer to undergo rBCS than other groups (p = 0.030). The most frequent reason for choosing rBCS was the patient's desire to minimize breast deformity and surgical wounds. CONCLUSIONS: Our study revealed that there is a low rate of patients who opt to undergo rBCS among patients who had undergone salvage surgery for IBTR. Discrepancies in perceptions regarding the surgical procedure for IBTR between patients and their surgeons may exist.

Otitis externa caused by Malassezia slooffiae complicated with mastoiditis: A case report.

Herein, we report a case of otitis externa caused by Malassezia slooffiae complicated with mastoiditis. A 70-year-old male complained of fever and severe otorrhea from left external auditory canal 2 months after undergoing a craniotomy to remove a hematoma. He had right-sided paralysis and undertook bed rest. Brain computed tomography revealed continuous fluid accumulation in the left mastoid air cells and middle ear from left external auditory canal in addition to leukocytosis and increased C-reactive protein level. The tympanic membrane was severely swelling. These results indicated the presence of otitis media and mastoiditis. Otorrhea culture showed large amounts of M. slooffiae. The administration of liposomal amphotericin B (L-AMB), the irrigation of external auditory canal with normal saline, and the application of topical ketoconazole ointment were started. The administration of L-AMB for 8 weeks and voriconazole, which was switched from L-AMB, for 4 weeks ameliorated his infection and he was transferred to another hospital to receive rehabilitation. From these results and his clinical course, the diagnosis of otitis externa caused by Malassezia slooffiae complicated with mastoiditis was made. And the possibility of the contamination by M. slooffiae was very low. Clinicians should be aware that M.slooffiae can provoke otological infections since M. slooffiae is the most common Malassezia sp. in external auditory canal.

[A Case of Chronic Expanding Hematoma of the Lower Abdomen after Reconstruction of Deep Inferior Epigastric Perforator Flap for Breast Cancer].

A 49-year-old woman who had surgery for left breast cancer and subsequently underwent a two-stage deep inferior epigastric perforator(DIEP)flap reconstruction. One month postoperatively, she became aware of abdominal distention and visited a local hospital. CT scan revealed subcutaneous fluid accumulation with capsular formation in the lower abdomen. Imaging findings and physical examination showed no abdominal wall scar hernia. After multiple puncture aspirations, fluid accumulation was observed again, and the possibility of a chronic expanding hematoma was considered. Later, hematoma removal, including the capsules, was performed; pathological findings showed no evidence of malignancy. No fluid retention was observed postoperatively. In cases where imaging evaluation reveals hematoma formation with capsules, hematoma removal, including the capsules, should be performed to avert the possibility of a chronic expanding hematoma.

Direct microorganism species identification and antimicrobial susceptibility tests from positive blood culture bottles using rapid Sepsityper Kit.

INTRODUCTION: We evaluated the performance of Rapid Sepsityper Kit in species identification (ID) and antimicrobial susceptibility testing (AST). METHODS: Positive blood culture bottles (n = 227) containing single microorganisms were enrolled. We compared the direct method using Rapid Sepsityper Kit for ID and AST with the conventional method. The analyses of ID and AST were performed using MALDI Biotyper and BD Phoenix platform, respectively. RESULTS: The direct ID method correctly identified 89.4% (203/227) of samples, and Gram-negative bacilli (95.2%) had a higher ID rate than Gram-positive cocci (84.4%). Five cases were misidentified, and non-acceptable identification was high among Streptococcus species. Direct AST results were obtained from 168 isolates. Non-acceptable ID occurred among 24 isolates; 4 Streptococcus species, and 31 isolates, which did not grow in the direct AST method, were excluded. A total of 1714 antibiotic susceptibility tests (625 from 69 Gram-positive cocci and 1089 from 99 Gram-negative bacilli) were performed. The direct AST methods showed 98.3% (1685/1714) of categorical agreement (CA), 0.7% (12/1714) of very major errors, 0.2% (4/1714) of major errors, and 0.8% (13/1714) of minor errors. Complete CA was obtained for methicillin-resistant Staphylococcus aureus and extended-spectrum beta-lactamase-producing Escherichia coli. CONCLUSIONS: The direct ID method using Rapid Sepsityper Kit and the direct AST method in combination with the BD Phoenix platform, which was associated with a reduction of turnaround time, may be a reliable approach for blood culture bottles. However, additional validation and further improvements, especially for Gram-positive cocci, would have an impact on microbiological diagnoses.

Identification of natural compounds extracted from crude drugs as novel inhibitors of hepatitis C virus.

Natural product-derived crude drugs are expected to yield an abundance of new drugs to treat infectious diseases. Hepatitis C virus (HCV) is an oncogenic virus that significantly impacts public health. In this study, we sought to identify anti-HCV compounds in extracts of natural products. A total of 110 natural compounds extracted from several herbal medicine plants were examined for antiviral activity against HCV. Using a Huh7-mCherry-NLS-IPS reporter system for HCV infection, we first performed a rapid screening for anti-HCV compounds extracted from crude drugs. The compounds threo-2,3-bis(4-hydroxy-3-methoxyphenyl)-3-butoxypropan-1-ol (#106) and medioresinol (#110), which were extracted from Crataegus cuneate, exhibited anti-HCV activity and significantly inhibited HCV production in a dose-dependent manner. Analyses using HCV pseudoparticle and subgenomic replicon systems indicated that compounds #106 and #110 specifically inhibit HCV RNA replication but not viral entry or translation. Interestingly, compound #106 also inhibited the replication and production of hepatitis A virus. Our findings suggest that C. cuneate is a new source for novel anti-hepatitis virus drug development.

Infected aortic aneurysm caused by Streptococcus pyogenes: A case report.

We reported the case with infected abdominal aortic aneurysm (AAA) caused by Streptococcus (S.) pyogenes. A seventy-seven-year-old man, who had the history of uncontrolled diabetes mellitus (DM), complained fever and abdominal pain. Abdominal computed tomography scan revealed the aneurysm above common iliac artery with false lumen. On admission, laboratory tests found marked elevation of inflammatory biomarkers. Thereby the infected AAA was suspected and blood culture was taken. The administration of meropenem (MEPM) and daptomycin (DAP) was started. Next day he underwent abdominal aortic replacement with prosthetic graft and debridement because of persistent abdominal pain and the enlargement of aneurysm. S. pyogenes in blood culture samples was identified by Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry. Same result was obtained from the tissue samples of the resected AAA. Then the diagnosis of infected AAA caused by S. pyogenes was made. Since isolated S. pyogenes showed the susceptibility to antibiotics tested including penicillin, antibiotics were changed to ampicillin (ABPC) for the de-escalation of antibiotics. He had kept the administration of ABPC for 4 weeks and transferred to another hospital for the further treatment of DM. The aneurysms by S. pyogenes are extremely rare, but we should note that S. pyogenes could induce the aneurysms.

High fibrin/fibrinogen degradation product value as a risk factor for progressive remote traumatic intracranial haemorrhage following neurosurgery.

INTRODUCTION: Remote traumatic intracranial haemorrhage (RTIH) may develop after neurosurgery. Recognition of the risk factors for RTIH before surgery might be of great value. The purpose of this study was to verify if the fibrin/fibrinogen degradation product (FDP) value may be a risk factor for RTIH. METHODS: This was a retrospective study of the data of 56 patients with traumatic intracranial hematomas shown on initial computed tomography (CT) who were treated with craniotomy or decompressive craniectomy and underwent a follow-up CT at a single centre over a period of approximately 10.5 years. We divided the patients into 2 groups: those who developed RTIH (Positive: P-group) and those who did not (Negative: N-group). We compared the 2 groups in terms of not only the laboratory data before surgery, but also patient age, sex, antiplatelet/antithrombotic medications received, cause of injury, and GCS score on arrival. RESULTS: RTIH was observed in 22 patients (P-group, 39.3%). The FDP value was the only significant risk factor identified in this study (p = 0.00076). The cut-off value was estimated on the basis of the area under the receiver operating characteristic (ROC) curve. The cut-off FDP value was 120 µg/mL (63.6% sensitivity and 85.3% specificity). CONCLUSIONS: FDP levels over 120 µg/mL were determined to be a risk factor for progressive RTIH after neurosurgery. We suggest the FDP level be checked before surgery for traumatic intracranial haemorrhage and follow-up CT be done as soon as possible after the surgery if the serum FDP level is over 120 µg/mL.

Establishment of infectious genotype 4 cell culture-derived hepatitis C virus.

To establish infectious genotype 4a (GT4a) cell culture-derived hepatitis C virus (HCVcc), we constructed full-length ED43 and 12 mutants possessing single or double mutations that increase ED43 replicon replication, and performed cell culture after RNA transfection. Sequential long-term culture of full-length ED43 RNA-transfected cells showed increased viral production in two ED43 mutants named ED43 QK/SI and TR/SI among the tested clones. These ED43 mutants possessed a common mutation, R1405G, in the NS3 helicase region and another mutation, D2413G or V2414A, in the NS5a-NS5b cleavage site. Furthermore, serial reinfection of naïve Huh7.5.1 cells accelerated peak HCV production at an earlier time point after every infection. After the fourth infection, we found a common mutation, R1405G, and six additional mutations in both ED43 QK/SI and TR/SI mutants. All seven mutations supported continuous viral production for more than 40 days in both ED43 QS-7M (QK/SI with seven mutations) and ED43 TS-7M (TR/SI with seven mutations). In addition, ED43 TS-7M did not require additional mutations for continuous virus culture up to 124 days. Both ED43 QS-7M and TS-7M were sensitive to the neutralizing E2 antibodies HCV1 and AR3A and the direct-acting antivirals, simeprevir, ledipasvir and sofosbuvir. In conclusion, we established an infectious ED43 strain containing adaptive mutations, which is important for the analysis of HCV genotype-specific pathogenesis, development of pan-genotypic agents and analysis of drug resistance.

Malignant transformation of pleomorphic xanthoastrocytoma and differential diagnosis: case report.

BACKGROUND: Pleomorphic xanthoastrocytoma (PXA) is a rare astrocytic glioma, characterized by large pleomorphic and frequently multinucleated cells, spindle and lipidized cells, a dense pericellular reticulin network, and numerous eosinophilic granular bodies according to the grade II glial tumor standards of the World Health Organization's (WHO) 2016 guidelines. PXA rarely transforms into anaplastic PXA or glioblastoma (GBM) and anaplastic PXA, classified as WHO grade III, has a more aggressive clinical behavior with poorer prognosis than PXA. CASE PRESENTATION: Here we describe an unusual case of PXA in a 19-year-old woman, first admitted with headache and a mass in the left temporal lobe in 2005 that was removed. Twelve years later, she returned with left temporal headache, diplopia and tinnitus. A local tumor recurrence was found, and a second resection was performed. The specimen showed highly malignant findings, such as necrosis, microvascular proliferation, and multiple mitoses. The integrated diagnosis was made as high grade glioma, probably derived from PXA. Immunohistochemical (IHC) stains were positive for oligo2, and approximately 21% positive for Ki-67, while negative for CD34, IDH1 R132H. INI1 and ATRX were retained. As the histological classification was glioblastoma, the patient received GBM-appropriate chemotherapy and radiation therapy and outpatient follow-ups have demonstrated no obvious symptoms for 1 year after surgery. Additional molecular analyses found BRAF V600E mutations in both resections, supporting the idea that the recurrent tumor had derived from PXA. CONCLUSIONS: This case highlights the complexities of differential diagnosis based on the World Health Organization's 2016 guidelines. More integrated criteria to differentiate anaplastic PXA from GBM and epithelioid GBM, combined with genetic screening results, might be needed.

Bloodstream infection by multidrug-resistant Streptococcus oralis in a leukemic patient with febrile neutropenia after hematopoietic stem cell transplantation.

We reported the case of a patient with leukemia who developed febrile neutropenia after hematopoietic stem cell transplantation. Blood culture results revealed the presence of Streptococcus oralis, while antimicrobial susceptibility testing showed the resistance to penicillin and cephem. Furthermore, isolates were not susceptible to either meropenem or daptomycin but not to vancomycin. S oralis is known to belong to Streptococcus mitis group and be a causative agent of bacteremia in the neutropenic patients, but multidrug resistance of S oralis is rare. Our findings suggest that we might pay attention to the emergence of the microorganisms acquiring multidrug resistance in neutropenic patients.

Thoracic aortic mycotic aneurysm due to Staphylococcus argenteus: A case report.

Staphylococcus argenteus was subdivided as a novel species from Staphylococcus aureus in 2014. We herein report a case of mycotic aneurysm caused by S. argenteus. A 59-year-old woman with diabetes and schizophrenia visited at the emergency room because of falling. Chest computed tomography revealed a left humerus fracture and a thoracic aortic aneurysm. With her elevated WBC count and CRP level, she was suspected to have a mycotic aneurysm. After being transferred to our hospital, vascular graft replacement surgery was performed. Isolates of blood cultures and surgical specimens were identified as S. argenteus by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MAS MALDI Biotyper Ver. 8.0). Although S. argenteus lacks staphyloxanthin, a carotenoid pigment, it is coagulase positive. In addition to traditional and automated biochemical identification systems, even MALDI-TOF MAS may misidentify the organism as S. aureus depending on its version. S. argenteus should be considered when coagulase-negative Staphylococcus like colonies are obtained from samples of S. aureus infection. To our knowledge, this is the first case of aortic mycotic aneurysm caused by S. argenteus in Japan. Although S. argenteus is considered less virulent than Staphylococcus aureus, we should closely monitor the prevalence and the clinical impact of this pathogen on community-acquired infections and health care-associated infections.

[A Case of Medullary Carcinoma of the Colon with Poor Prognosis].

An 87-year-oldwoman was referredowing to lightheadedness. Severe anemia(Hb 3.9 g/dL)was detected, and colonoscopy revealeda circumferential elevatedlesion at the transverse colon(Group 5, por). The patient was diagnosed with colon cancer(cT4a, N0, M0, Stage Ⅱ), andright hemicolectomy was performed. Immunochemical analysis showedthat the lesion was MLH1- andPMS2- and confirmed a diagnosis of medullary carcinoma. Although the patient was discharged 48 days after surgery without any incident, she was readmitted because of lower leg edema. Liver metastasis and peritoneal dissemination were suspectedon performing computedtomography, andthe patient died3 5 days after readmission. Medullary carcinoma has molecular pathological features such as methylation of the promoter region andassociatedattenuation of MLH1 protein expression, as well as microsatellite instability. The prognosis for medullary carcinoma is relatively good comparedto that for poorly differentiatedad enocarcinoma, though the present case hada poor prognosis. Herein, we report a literature review.

False-positive blood culture results in patients with hematologic malignancies.

Blood cultures are the most valuable tool when bacteremia is clinically suspected. Technical advances have led to the development of automated blood culture systems to detect bacterial infections. Usually positive signals in automated blood culture systems result from the proliferation of microorganisms. Cases are classified as false-positive when the automated blood culture system produces a positive signal but no microorganisms are detected on Gram-stained smears and no microorganism growth is observed in blood subcultures. False-positive blood culture results are very rare in patients with hematologic malignancies. Recently, we encountered four patients who had false-positive blood culture results. Two of the patients were diagnosed with acute leukemia, involving hyperleukocytosis and an excess of blasts. The other two patients were diagnosed with acute leukemia and diffuse large B cell lymphoma with leukocytopenia. Although hypercapnia or acidosis, apart from hyperleukocytosis, might also cause false-positive results, our cases clearly did not have these conditions. We should be aware of the possibility that false-positive blood culture results can occur in patients with leukocytopenia, as well as hyperleukocytosis. To understand the mechanisms responsible for the observed false-positive results, additional studies are needed after the accumulation of similar cases.

Hepatic gas gangrene caused by Clostridium novyi.

We report the case of a patient with advanced gastric cancer and multiple liver metastases, who presented with bacteremia and hepatic gas gangrene caused by Clostridium novyi (C. novyi). The gas gangrene caused abscesses to form within metastatic lesions. This case highlights the antitumor effects of C. novyi in human.

[A Case of Hepatocellular Carcinoma Complicated with Idiopathic Thrombocytopenic Purpura].

The patient was a 72-year-oldwoman. She had been diagnosed with idiopathic thrombocytopenic purpura(ITP), hepatitis B, and diabetes mellitus. She was admitted to our hospital because of anemia andvomiting of blood vomiting and was diagnosed with hepatocellular carcinoma at S6. A splenectomy was performed, with a temporary improvement of her platelet count. We tried to control the platelet count with medication and performed transcatheter arterial embolization(TACE)3 times. However, the tumor size decreased only slightly anda new tumor was observed on S2. Therefore, we increased the patient's platelet count to 109×10 4/mL and performed a partial hepatectomy of 4 lesions. The postoperative complications included intraabdominal abscess, but there was no bleeding and the patient was discharged on POD 114. Platelet count is often difficult to maintain in patients diagnosed with ITP. We report our experiences and also provide a discussion of a case of operated hepatocellular carcinoma complicated with refractory ITP.

[A Case of a Duodenal GIST Observed as a Non-Functional Pancreatic Neuroendocrine Tumor].

A 67-year-oldman was referredto our hospital because his CEA level was increasing. In March 2007, abdominal computed tomography(CT)showedthe presence of a tumor(30mm in diameter)in the pancreatic head. Upon close inspection, the patient was diagnosed with a non-functional pancreatic neuroendocrine tumor and was observed. In September 2016, the patient showedhyperglycemia, liver dysfunction, andelevation of tumor markers. CT revealeda tumor(42mm in diameter) in the pancreatic head. It hadincreasedmore than before. We diagnosedhim with a gastrointestinal stromal tumor(GIST)of the duodenum based on endoscopic ultrasound-guided fine-needle aspiration biopsy and performed pancreaticoduodenectomy. Immunohistochemical staining showedpositive c-kit, andmore than 10%positive MIB-1. Currently, the patient is alive after the surgery.

[Curative Resection for Liver Metastasis Ten Years after Surgery for Rectosigmoid Cancer-A Case Report].

Here, we report the case of a 73-year-oldfemale patient, who previously underwent high anterior resection for rectosigmoidcancer at the age of 63. Her scheduled5 years of follow-up after colorectal surgery hadbeen finished, but she kept undergoing endoscopic mucosal resection for colorectal polyps every 1 or 2 years since then. Blood examination 10 years 6 months after surgery for rectosigmoidcancer revealedthat the value of her serum CEA was 5.5 ng/mL, which was slightly higher than the normal range. Contrast-enhancedCT showedan irregular-shapedtumor with a diameter of 3 cm in which the contrast of the peripheral area was mainly emphasized. When combining the results of MRI and PET-CT examinations, the liver tumor was clinically diagnosed as either intrahepatic cholangiocarcinoma or metastatic liver cancer. Since the first choice of therapy was tumor resection for both diagnoses, S8 subsegmental hepatectomy was performed 10 years 8 months after surgery for rectosigmoidcancer. HE staining of the resectedspecimen showedwell or moderately differentiatedad enocarcinoma, andits immunostaining findings were as follows: CDX-2: positive, CK20: positive, CK7: negative. It was pathologically diagnosed as liver metastasis from rectal cancer. It is rare for colorectal cancer to have metachronous liver metastasis more than 10 years after surgery. However, in any case where a tumor marker for colorectal cancer increases, it is necessary to examine carefully with the possibility of any metastasis in mind.