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Background: Sterility and safety assurance of hematopoietic stem cell (HSC) products is critical in transplantation. Microbial contamination can lead to product disposal and increases the risk of unsuccessful clinical outcomes. Therefore, it is important to implement and maintain good practice guidelines and regulations for the HSC collection and processing unit in each hospital. We aimed to share our experiences and suggest strategies to improve the quality assurance of HSC processing. Methods: We retrospectively analyzed microbial culture results of 11,743 HSC products processed over a 25-year period (January 1996 to May 2021). Because of reorganization of the HSC management system in 2008, the 25-year period was divided into periods 1 (January 1996 to December 2007) and 2 (January 2008 to May 2021). We reviewed all culture results of the HSC products and stored aliquot samples and collected culture results for peripheral blood and catheter samples. Results: Of the 11,743 products in total, 35 (0.3%) were contaminated by microorganisms, including 19 (0.5%) of 3,861 products during period 1 and 16 (0.2%) of 7,882 products during period 2. Penicillium was the most commonly identified microorganism (15.8%) during period 1 and coagulase-negative Staphylococcus was the most commonly identified (31.3%) during period 2. HSC product contamination occurred most often during HSC collection and processing. Conclusions: The contamination rate decreased significantly during period 2, when the HSC management system was reorganized. Our results imply that handling HSC products by trained personnel and adopting established protocols, including quality assurance programs, aid in decreasing the contamination risk. [ABSTRACT FROM AUTHOR]

Antibacterial low-density polyethylene (LDPE)- and poly (lactide)/poly (butylene adipate-co-terephthalate) (PLA/PBAT)-based films incorporated with elemental sulfur (ES) and sulfur nanoparticles (SNPs) were prepared using a blow extrusion method for food packaging applications. Flexible and free-standing films were manufactured using an industrial processing method without any modification. The films were characterized using ultraviolet (UV)--visible spectroscopy, field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA). Also, film properties include optical, mechanical, surface hydrophobicity, thermal stability and antibacterial activity. The addition of ES and SNP significantly reduced the light transmittance (both UV and visible light) of LDPE- and PLA/PBAT-based films and slightly reduced mechanical properties but did not affect thermal stability. The ES- and SNP-added films showed apparent antibacterial activity against the Gram-positive foodborne pathogenic bacteria (Listeria monocytogenes). In general, SNP showed superior film properties and antibacterial properties compared to ES, but ES also showed comparable properties as SNP. Antibacterial LDPE- and PLA/PBAT-based films can be produced on an industrial scale and used in the packaging of refrigerated foods susceptible to L. monocytogenes contamination. [ABSTRACT FROM AUTHOR]

We report a phase I pharmacological study of an oral formulation of CKD-516, a vascular-disrupting agent, in patients with refractory solid tumors. Twenty-seven patients (16 in the dose-escalation cohort and 11 in the expansion cohort) received a single daily dose (5-25 mg) of CKD-516 five days per week. Nausea (67%) and diarrhea (63%) were the most common treatment-related adverse events. The recommended phase II dose of oral CKD-516 was 20 mg/d (15 mg/d with a body surface area (BSA) <1.65 m2). Notably, S-516 half-lives in patients receiving 15-20 mg CKD- 516/d significantly differed between patients with and without splenomegaly that is suggestive of portal hypertension associated with liver cirrhosis (6.1 vs 4.6 hours, respectively). Of 11 patients without splenomegaly who completed at least one cycle of a daily CKD-516 dose of either 15 or 20 mg, only one patient (9.1%) suffered from any dose-limiting toxicity. We conclude that a daily oral dose of 15 or 20 mg CKD-516 five days per week could be tolerable in patients without liver cirrhosis. [ABSTRACT FROM AUTHOR]

Although efficient human-to-human transmission of avian influenza virus has yet to be seen, in the past two decades avian-to-human transmission of influenza A viruses has been reported. Influenza A/H5N1, in particular, has repeatedly caused human infections associated with high mortality, and since 1998 the virus has evolved into many clades of variants with significant antigenic diversity. In 2013, three (A/H7N9, A/H6N1, and A/H10N8) novel avian influenza viruses (AIVs) breached the animal-human host species barrier in Asia. In humans, roughly 35% of A/H7N9-infected patients succumbed to the zoonotic infection, and two of three A/H10N8 human infections were also lethal; however, neither of these viruses cause influenza-like symptoms in poultry. While most of these cases were associated with direct contact with infected poultry, some involved sustained human-to-human transmission. Thus, these events elicited concern regarding potential AIV pandemics. This article reviews the human incursions associated with AIV variants and the potential role of pigs as an intermediate host that may hasten AIV evolution. In addition, we discuss the known influenza A virus virulence and transmission factors and their evaluation in animal models. With the growing number of human AIV infections, constant vigilance for the emergence of novel viruses is of utmost importance. In addition, careful characterization and pathobiological assessment of these novel variants will help to identify strains of particular concern for future pandemics. [ABSTRACT FROM AUTHOR]

Background. Although Middle East Respiratory Syndrome coronavirus (MERS-CoV) is characterized by a risk of nosocomial transmission, the detailed mode of transmission and period of virus shedding from infected patients are poorly understood. The aims of this study were to investigate the potential role of environmental contamination by MERS-CoV in healthcare settings and to define the period of viable virus shedding from MERS patients. Methods. We investigated environmental contamination from 4 patients in MERS-CoV units of 2 hospitals. MERS-CoV was detected by reverse transcription polymerase chain reaction (PCR) and viable virus was isolated by cultures. Results. Many environmental surfaces of MERS patient rooms, including points frequently touched by patients or healthcare workers, were contaminated by MERS-CoV. Viral RNA was detected up to five days from environmental surfaces following the last positive PCR from patients' respiratory specimens. MERS-CoV RNA was detected in samples from anterooms, medical devices, and air-ventilating equipment. In addition, MERS-CoV was isolated from environmental objects such as bed sheets, bedrails, IV fluid hangers, and X-ray devices. During the late clinical phase of MERS, viable virus could be isolated in 3 of the 4 enrolled patients on day 18 to day 25 after symptom onset. Conclusions. Most of touchable surfaces in MERS units were contaminated by patients and health care workers and the viable virus could shed through respiratory secretion from clinically fully recovered patients. These results emphasize the need for strict environmental surface hygiene practices, and sufficient isolation period based on laboratory results rather than solely on clinical symptoms. [ABSTRACT FROM AUTHOR]

배경 Recent studies reported detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in various clinical specimens suggesting that in addition to respiratory secretions, other transmission routes exist. Despite serious public concerns, the transmission mechanisms responsible for community spread of this virus are largely unknown. 방법 To demonstrate whether various clinical specimens contain the viable virus, we collected naso/oropharyngeal swabs, saliva, urine, and stool from five COVID-19 patients and performed a quantitative polymerase chain reaction (qPCR) to assess viral load. Specimens positive by qPCR were subjected to virus isolation in Vero cells. We also used urine and stool samples to intranasally inoculate ferrets and evaluated the virus titers in nasal washes on 2, 4, 6, and 8 days post-infection (dpi). 결과 SARS-CoV-2 RNAs were detected in all naso/oropharyngeal swabs, saliva, urine, and stool samples collected between days 8 to 30 of the clinical course. Notably, viral loads in urine, saliva, and stool samples were almost equal to or higher than those in naso/oropharyngeal swabs (urine 1.08±0.16 – 2.09±0.85 log10 copies/ml, saliva 1.07±0.34 – 1.65±0.46 log10 copies/ml, stool 1.17±0.32 log10 copies/ ml, naso/oropharyngeal swabs 1.18±0.12 – 1.34±0.30 log10 copies/ml). Further, viable SARS-CoV-2 was isolated from naso/oropharyngeal swabs and saliva of COVID-19 patients, as well as nasal washes of ferrets inoculated with patient urine or stool. 결론 Viable SARS-CoV-2 was demonstrated in saliva, urine, and stool from COVID-19 patients up until days 11 to 15 of the clinical course. This result suggests that viable SARS-CoV-2 can be secreted in various clinical samples as well as respiratory specimens. [ABSTRACT FROM AUTHOR]