Serum proteomics of severe fever with thrombocytopenia syndrome patients.

BACKGROUND: Dabie bandavirus, also termed as severe fever with thrombocytopenia syndrome virus (SFTSV), was first isolated in China in 2010. At this time, the virus was found to have spread to South Korea, Japan, and other countries. A high case fatality rate is reported for SFTS, ranging from 12-50% within various sources. Several omics for clinical studies among SFTS patients as well as studies of cultured SFTSV have attempted to characterize the relevant molecular biology and epidemiology of the disease. However, a global serum proteomics analysis among SFTS patients has not yet been reported to date. METHODS: In the current study, we evaluated comparative serum proteomics among SFTS patients (eight recovered patients and three deceased patients) with the goal of identifying the protein expression patterns associated with the clinical manifestations of SFTS. RESULTS: The proteomic results in the current study showed that the coagulation factor proteins, protein S and protein C, were statistically significantly downregulated among the deceased patients. Downregulation of the complement system as well as prolonged neutrophil activation were also observed. Additionally, the downstream proteins of tumour necrosis factor alpha, neutrophil-activating cytokine, and interleukin-1ß, an inflammatory cytokine, were overexpressed. CONCLUSIONS: Thrombocytopenia and multiple organ failure are the major immediate causes of death among SFTS patients. In this study, serum proteomic changes related to thrombocytopenia, abnormal immune response, and inflammatory activation were documented in SFTS patients. These findings provide useful information for understanding the clinical manifestations of SFTS.

Rapid Biosensor of SARS-CoV-2 Using Specific Monoclonal Antibodies Recognizing Conserved Nucleocapsid Protein Epitopes.

Coronavirus disease 2019 (COVID-19), the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is characterized by symptoms such as fever, fatigue, a sore throat, diarrhea, and coughing. Although various new vaccines against COVID-19 have been developed, early diagnostics, isolation, and prevention remain important due to virus mutations resulting in rapid and high disease transmission. Amino acid substitutions in the major diagnostic target antigens of SARS-CoV-2 may lower the sensitivity for the detection of SARS-CoV-2. For this reason, we developed specific monoclonal antibodies that bind to epitope peptides as antigens for the rapid detection of SARS-CoV-2 NP. The binding affinity between antigenic peptides and monoclonal antibodies was investigated, and a sandwich pair for capture and detection was employed to develop a rapid biosensor for SARS-CoV-2 NP. The rapid biosensor, based on a monoclonal antibody pair binding to conserved epitopes of SARS-CoV-2 NP, detected cultured virus samples of SARS-CoV-2 (1.4 × 103 TCID50/reaction) and recombinant NP (1 ng/mL). Laboratory confirmation of the rapid biosensor was performed with clinical specimens (n = 16) from COVID-19 patients and other pathogens. The rapid biosensor consisting of a monoclonal antibody pair (75E12 for capture and the 54G6/54G10 combination for detection) binding to conserved epitopes of SARS-CoV-2 NP could assist in the detection of SARS-CoV-2 NP under the circumstance of spreading SARS-CoV-2 variants.

Ultrastructural visualization of Orientia tsutsugamushi in biopsied eschars and monocytes from scrub typhus patients in South Korea.

Scrub typhus, which is caused by Orientia tsutsugamushi, is a public health problem in the Asian-Pacific region and is the third most frequently reported infectious disease in South Korea. While ultrastructural studies have been performed on O. tsutsugamushi in murine fibroblasts, its variable locations in patients have hampered similar studies in humans. Two patients with scrub typhus agreed to provide an eschar biopsy and peripheral blood, respectively. Transmission electron microscopy was performed separately on the necrotic crust and perifocal skin of the eschar, the peripheral blood, and the infected murine L cells. O. tsutsugamushi was located within or adjacent to the outermost layer of the perifocal inflamed skin of the eschar but not in the necrotic centre. O. tsutsugamushi in peripheral blood monocytes exhibited the characteristic features of O. tsutsugamushi in L cells, namely, nearly round shaped bacteria with a size of 1-2 µm and a double membrane bearing a clear halo-like outer layer. The findings confirmed that the bacterium was predominantly located in the inflamed skin around the eschar and that the bacterium had the same ultrastructural features in human monocytes as in L cells. These findings suggest that the perifocal area, not the necrotic centre, should be sampled for diagnosis.

A Case of Jejunal Intussusception caused by Burkitt Lymphoma in an Acquired Immunodeficiency Syndrome Patient.

Non-Hodgkin's lymphoma of B-cell type is the second most common neoplasm after Kaposi's sarcoma among patients with human immunodeficiency virus infection. Most non-Hodgkin's lymphoma cases that are associated with acquired immunodeficiency syndrome (AIDS) involve extranodal sites, especially the digestive tract and the central nervous system. We report a case of multiple jejunal intussusception caused by Burkitt lymphoma in a 42-year-old AIDS patient. Upper gastrointestinal endoscopy and surgical biopsy were performed and a complete diagnostic study including histological and immunohistochemical analyses showed Burkitt lymphoma.

Successfully Managed Acute Transverse Myelitis Related to Scrub Typhus and Serial Image Findings.

Central nervous system involvement manifesting as meningitis or meningoencephalitis is a known complication of scrub typhus, but very few spinal cord lesions such as acute transverse myelitis (ATM) have been reported in association with this disease. Scrub typhus patients with a spinal lesion present with neurologic symptoms including dysuria, motor, and sensory weakness. Herein, we describe a rare case of ATM associated with scrub typhus. Clinical characteristics, cerebrospinal fluid cytology, Orientia tsutsugamushi serum antibody titer, and serial magnetic resonance imaging scans resulted in a diagnosis of ATM associated with scrub typhus.

Splenic infarction associated with acute infectious mononucleosis due to Epstein-Barr virus infection.

The purpose of this study was to report a case of a previously healthy 20-year-old woman diagnosed with splenic infarction following infectious mononucleosis (IM) by Epstein-Barr virus (EBV) infection and to perform the first systematic review of the clinical characteristics of splenic infarction associated with IM. A systematic review was conducted using English, French, and Japanese literatures of splenic infarction associated with IM due to EBV infection published between 1961 and 2015 in PubMed Medline. A total of 19 cases were extracted from the collected articles. Left upper quadrant (LUQ) pain was observed in 15 (79%) patients. Splenectomy was performed in five (26%) cases, among which four patients presented with stable vital signs. Splenic rupture was accompanied in two (10%) patients. The median time from the onset of IM symptoms to the diagnosis of splenic infarction was 5 days (range, 1-25 days). Fourteen (74%) of 19 patients experienced improvement through medical treatment, and there were no deaths. Splenic infarction associated with IM due to EBV infection can show a favorable clinical outcome after medical treatment. Clinicians should consider the possibility of splenic infarction when patients with IM experience LUQ pain. J. Med. Virol. 89:332-336, 2017. © 2016 Wiley Periodicals, Inc.

Cross-protection against Vibrio cholerae infection by monoclonal antibodies against Vibrio vulnificus RtxA1/MARTXVv.

Gram-negative Vibrio species secrete multifunctional autoprocessing repeats-in-toxin (MARTX) toxins associated with bacterial pathogenesis. Here, the cross-reactivity and cross-protectivity of mAbs against V. vulnificus RtxA1/MARTXVv was evaluated. Passive administration of any of these mAbs (21RA, 24RA, 46RA, 47RA and 50RA) provided strong protection against lethal V. cholerae infection. Interestingly, 24RA and 46RA, which map to the cysteine protease domain of V. cholerae MARTXVc , inhibited CPD autocleavage in vitro; this process is involved in V. cholerae pathogenesis. These results generate new insight into the development of broadly protective mAbs and/or vaccines against Vibrio species with MARTX toxins.

Fabrication and characterization of SnO2/ZnO gas sensors for detecting toluene gas.

This study investigates the use of SnO2, ZnO, Ag, Au, Cu, In, Pd, Ru and carbon black to improve the sensitivity of a gas sensor for detecting toluene gas. Metal-SnO2/ZnO thick films were screen-printed onto Al2O3 substrates with platinum electrodes. The physico-chemical properties of the sensor materials were characterized using SEM/EDS, XRD, and BET analyses. Measuring the electrical resistance of each sensor as a function of the gas concentration determined the sensing characteristics. The sensors were tested using toluene, benzene, xylene, ethanol, methanol, ammonia and trimethylamine vapors with concentrations of 1-2000 ppm. The gas sensing properties of metal-SnO2/ZnO thick films depended on the content and variety of metals and the content of carbon black. The optimum condition of sensor material for toluene gas detection is operation temperature 300 degrees C and when metal catalyst Cu and carbon black were added. The best sensitivity and selectivity for toluene gas at 300 degrees C resulted from doping with 5 wt.% carbon black, 1 wt.% Cu and 20 wt.% ZnO to SnO2.

Electrophoretic deposition of iron catalyst on C-fiber textiles for the growth of carbon nanofibers.

In this study, carbon nanofibers synthesis has been conducted by chemical vapor deposition on C-fiber textiles coated with an iron catalyst via electrophoretic deposition. C-fiber textiles were oxidized with nitric acid before the iron catalyst was plated by electrophoretic deposition. Due to oxidation, the hydroxyl group was created on the C-fiber textiles and was used as an active site for iron catalyst deposition. It was verified that the iron catalyst was deposited on the C-fiber textiles, while current, voltage, and deposition time varied and the concentration of electrolyte was kept constant in electrophoretic deposition. After being deposited, the iron particles were dried in oven for 24 hours and reduced by hydrogen gas in a furnace. Ethylene gas was introduced for the growth of carbon nanofibers and the growth temperature was then varied to find the optimal growth temperature of the carbon nanofibers. Thus, the characteristics of carbon nanofibers were analyzed by Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), N2-sorption (BET), X-Ray Diffraction (XRD), and X-ray Photoelectron Spectroscopy (XPS). It is verified that the iron particles were most evenly deposited at 0.1 A for 3 minutes. Carbon nanofibers grew to 150-200 nm most evenly at 600 degrees C via temperature variations in CVD.

Characteristics of invasive Staphylococcus aureus infections in three regions of Korea, 2009-2011: a multi-center cohort study.

BACKGROUND: Despite the importance of invasive Staphylococcus aureus (ISA) infection, its overall burden in non-selected populations has only been defined in a small number of studies in Europe and North America. To define the characteristics of ISA infections in Korea, we conducted a multi-center cohort study to estimate population-based incidence rates. METHODS: We conducted a multicenter prospective cohort study at nine university-affiliated active-surveillance core centers (ASCs) in three regions of Korea. To cover all available clinical microbiologic laboratories, we classified the laboratories in these regions into three groups according to their clinical environment as: 1) Nine ASCs, 2) Five major commercial laboratories and 3) Forty-four acute-care hospital-affiliated microbiology laboratories. We requested all the laboratories to report prospectively their numbers of cases of S. aureus isolated from normally sterile sites. Detailed clinical information was collected about the cases in the nine ASCs. RESULTS: From 1 July 2009 to 30 June 2011, a total of 1,198 cases of ISA infection were identified at the nine ASCs, including 748 (62%) methicillin-resistant S. aureus (MRSA) infections. Most (81%) ISA infections were healthcare-associated (HCA): 653 (55%) hospital-onset and 322 (27%) community-onset. 223 (19%) were community-associated infections. The most common primary diagnosis was catheter-associated infection (225 cases, 19%). Respiratory tract infection (160, 13%), skin & soft tissue (152, 13%) and bone & joint infections (120, 10%) were also common. 30-day and 12-week mortality rates were 25.6% (262/1,024) and 36.5% (314/860), respectively. Complications, including metastatic infection within 12 weeks, occurred in 17.8% of ISA infections. The most common site of metastatic infection was the lung (9.8%, 84/860). Based on the total of 2,806 observed cases of ISA infection, estimated annual rates of ISA and invasive MRSA infections were 43.3 and 27.7 per 100,000 populations, respectively. CONCLUSIONS: Our data provide important information about the clinical characteristics of ISA infections. We estimate that over 21,000 ISA infections and 13,000 invasive MRSA infections occurred in Korea in 2010.

Development of a detection sensor for lethal H2S gas.

The gas which may be lethal to human body with short-term exposure in common industrial fields or workplaces in LAB may paralyze the olfactory sense and impose severe damages to central nervous system and lung. This study is concerned with the gas sensor which allows individuals to avoid the toxic gas that may be generated in the space with residues of organic wastes under 50 degrees C or above. This study investigates response and selectivity of the sensor to hydrogen sulfide gas with operating temperatures and catalysts. The thick-film semiconductor sensor for hydrogen sulfide gas detection was fabricated WO3/SnO2 prepared by sol-gel and precipitation methods. The nanosized SnO2 powder mixed with the various metal oxides (WO3, TiO2, and ZnO) and doped with transition metals (Au, Ru, Pd Ag and In). Particle sizes, specific surface areas and phases of sensor materials were investigated by SEM, BET and XRD analyses. The metal-WO3/SnO2 thick films were prepared by screen-printing method. The measured response to hydrogen sulfide gas is defined as the ratio (Ra/R,) of the resistance of WO3ISnO2 film in air to the resistance of WO3/SnO2 film in a hydrogen sulfide gas. It was shown that the highest response and selectivity of the sensor for hydrogen sulfide by doping with 1 wt% Ru and 10 wt% WO3 to SnO2 at the optimum operating temperature of 200 degrees C.

Catheter-related bacteremia caused by multidrug-resistant Leclercia adecarboxylata in a patient with breast cancer.

We report a multidrug-resistant strain of Leclercia adecarboxylata responsible for catheter-related bacteremia in a 47-year-old female with breast cancer. The isolated strain was resistant to several ß-lactams, aminoglycosides, and folate pathway inhibitors and harbored bla(TEM-1) and bla(CTX-M) group 1 and intl1 genes (dfrA12-orfF-aadA2) as genetic determinants for resistance. Based on a review of the L. adecarboxylata literature, there have been only 4 reports of antibiotic-resistant strains. To our knowledge, this is the first report of an L. adecarboxylata strain with simultaneous resistance to ß-lactams, aminoglycosides, and sulfonamides.

Impact of a national hospital evaluation program using clinical performance indicators on the use of surgical antibiotic prophylaxis in Korea.

OBJECTIVES: Clinical performance measurement in surgical antibiotic prophylaxis (SAP) was implemented as part of a national hospital evaluation program (NHEP) in Korea in 2007. This study investigated changes in SAP quality before and after the implementation of clinical performance measurement. METHODS: The medical records of patients who underwent three types of surgery that were included for assessment in the NHEP (NHEP surgery) - arthroplasty, gastrectomy, and hysterectomy - and two other types of non-NHEP assessment surgery - craniotomy and spine surgery (non-NHEP surgery) - at six hospitals, from August to October in 2006-2008, were retrospectively reviewed. Three clinical indicators of SAP (antibiotic selection, timing of administration of the first dose, and duration) and the development of surgical site infections (SSIs) were compared before and after implementation. RESULTS: A total of 1949 patients were enrolled: 356 arthroplasty, 273 gastrectomy, 615 hysterectomy, 168 craniotomy, and 537 spinal surgery. There were no significant changes in age, gender, wound class, or ASA score for each surgery during the study period. From 2007, SAP quality was significantly improved in NHEP surgery for the three clinical indicators. The timing of administration of the first dose was most markedly improved. SAP quality was also improved in non-NHEP surgery, but not as much as in NHEP surgery. Changes in the SSI rates for each surgery were not significant. CONCLUSIONS: Hospital evaluation using clinical performance indicators can considerably improve the use of SAP. Further studies are warranted to investigate whether this hospital evaluation will decrease the development of SSIs.

Severity predictors in eschar-positive scrub typhus and role of serum osteopontin.

We prospectively evaluated severity predictors in terms of host, microorganism, and treatment factors in 153 eschar-positive scrub typhus patients. Severity was assessed with the Acute Physiology and Chronic Health Evaluation (APACHE) II score (< 10 versus ≥ 10) and predefined criteria of severe complications. Genotypes of Orientia tsutsugamushi were determined. Independent risk factors for severity (APACHE II score ≥ 10) were old age, diabetes mellitus, serum osteopontin > 100 ng/mL, and a group of underlying diseases (congestive heart failure, cerebrovascular disease, chronic liver disease, bronchial asthma, and chronic obstructive lung diseases). Anemia (≤ 10 g/dL) and C-reactive protein > 10 mg/dL were indicators of current severity. Neither the delay in antibiotics administration nor strain types (Boryong, Taguchi, or Kanda/Kawasaki) contributed to the severity. The risk factors for severe complications were similar. Serum osteopontin > 100 ng/mL had a negative predictive value of 96% for severe complications. This marker can be used to rule out severe disease status.

Tumor necrosis factor-α and mortality in patients infected with Vibrio vulnificus.

Serum tumor necrosis factor-α (TNF-α) was evaluated in Vibrio vulnificus-infected patients at admission. The median TNF-α concentration in the non-survivor group was determined to be 261.0 pg/mL, in contrast to 69.5 pg/mL in the survivor group (P = 0.001). Hence, serum TNF-α concentration may potentially be an early predictor of the mortality in patients with Vibrio septicemia.