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1.
International Journal of Radiation Oncology, Biology, Physics ; 114(3):e14-e14, 2022.
Article in English | Academic Search Complete | ID: covidwho-2036090

ABSTRACT

Two landmark randomized controlled trials (RCT) of external beam accelerated partial breast irradiation (EB-APBI) using 38.5 Gy/10 fractions (F) BID demonstrated excellent cancer control outcomes in appropriately selected patients but conflicting results regarding cosmesis. A recent RCT reported high rates of acceptable cosmesis using 30 Gy/5F QOD, making the most appropriate schedule for EB-APBI unclear. We utilized the BID regimen largely until the COVID-19 pandemic with strict contouring, dosimetric, and planning guidelines for gross/clinical/planning target volumes (GTV/CTV/PTV) and organs-at-risk (OAR). We report our experience with BID and QOD EB-APBI with a hypothesis that our treatment planning approach would result in acceptable acute toxicity and cosmesis. We identified patients that received EB-APBI from 4/2017 through 12/2021. Clinical, pathologic, acute toxicity, cosmesis and dosimetric data for the lumpectomy (Lump) GTV/CTV/PTV and key OARs (ipsilateral breast [IB V50%, V80% and V100% of the Rx dose] heart (mean dose, V5% Rx dose;V3 Gy], ipsilateral lung [IL V30% Rx dose] and mean total lung dose [TLD]) were collected. Cosmesis was physician-reported using the 4-point NRG Oncology/RTOG Global Cosmetic Score (GCS): Excellent (E)/Good (G)/Fair (F)/Poor (P). We report descriptive statistics to summarize our results. 245 patients were included with median follow-up 19 months (IQR, 9-30 months): median age, 66 y (IQR, 59-71 y);51% left-sided;82% invasive;100% invasive tumors HR+/HER2-;95% of DCIS HR+;median invasive tumor size 9.5 mm (IQR, 6-13 mm) and DCIS size 8mm (IQR, 4-12 mm);96% nodal surgery in invasive disease. Fractionation was BID in 55%, QOD in 45%. 3DCRT was used in 88% with median 6 fields (IQR, 5-7) and 96% were treated prone. Median Lump PTV eval volume was 176 mL and median breast volume 1335 mL resulting in median breast V50%Rx Dose=40.3% (IQR, 34.5-45.8%) and median breast V100=15.6% (IQR, 10.2-18.6%). Lump PTV coverage was high (median V95=100%). The mean heart dose was 35 cGy (IQR, 15-59 cGy), heart V5%=1.1% (IQR, 0-8.1%), and median heart V3Gy=0% (0-0.5%). The IL V30% (median 0%, IQR 0-0.4%) and TLD (median 49 cGy, IQR 26-93.1 cGy) were also low. The majority of patient had no acute toxicity (55% grade 0 dermatitis;57% grade 0 fatigue;97% grade 0 pruritis). The rate of E/G cosmesis was 97.1% (N=238) and F/P 2.9% (N=7). In patients with at least 2 years follow-up, rates were 96% E/G (N=95) and 4% F/P (N=4). The IB V100 was marginally associated with increased odds of F/P cosmesis (OR=1.18, 95% CI 0.99-1.42, p=0.07). With multiple-field 3DCRT in the prone position, EB-APBI can be delivered with low toxicity and great cosmetic results with BID or QOD treatment. Given the low rate of F/P cosmesis, longer follow-up is needed to confirm stability of these results and to help identify optimal dose-volume parameters to minimize the rate of F/P cosmesis. [ FROM AUTHOR] Copyright of International Journal of Radiation Oncology, Biology, Physics is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

2.
International Journal of Radiation Oncology, Biology, Physics ; 114(3):e10-e10, 2022.
Article in English | Academic Search Complete | ID: covidwho-2036089

ABSTRACT

In March 2020, a 1-week hypofractionated adjuvant breast radiotherapy schedule, 26 Gy in 5 fractions, was implemented to reduce the risk of COVID 19 virus for patients and staff without compromising on cancer outcomes. This prospective observational study aims to report late toxicities at 1-year and to confirm feasibility and acceptability of this new schedule for patients. – Patient reported outcome measures were recorded at baseline, 3 months, 6 months and 1 year following treatment completion. The presence of breast pain, swelling, hypersensitivity and skin problems, arm or shoulder pain, restricted arm movement and arm swelling were recorded using the EORTC QLQ BR45. Virtual teleconferencing without video was utilized at baseline, 3 months, 6 months and 1-year. Patients were invited to use video at the 1-year assessment for a physician-based assessment. To assess the experience of patients, a survey including 12 questions related to understanding, experiences of and benefits of ultrahypofractionated radiotherapy was developed and patients were invited to participate at the 1-year consultation. In total, 135 consecutive patients were enrolled Mar - Aug 2020. 121/135 (90%) patients completed the 1-year toxicity assessment and at least one other assessment. 30/121 (25%) patients received a sequential boost. The majority of patients reported no toxicity or a mild toxicity at all three time points, 76% (83/109) at 3 months, 76% (82/108) at 6 months, and 82% (99/121) at 1-year. At 1 year 17% (20/121) of patients reported a moderate toxicity, the most common being breast pain (6/121). 2% (2/121) of patients reported a marked toxicity, both reported multiple marked toxicities including appearance of breast, firmness and skin changes. For the 30 patients who received a boost a moderate toxicity was reported by 17% (5/30) at 1 year and 3% (1/30) reported a marked toxicity. There was one confirmed case of ipsilateral recurrence at 1-year. Only 30/121 patients were open to using video for the 1-year physician-based assessment. Regarding patient reported experience 90% (101/112) felt informed about the 1-week radiotherapy schedule, and 88% (99/112) felt informed about possible side effects and 94% (105/122) felt supported by the medical team throughout their treatment course. Only 49% (55/112) reported they would have been open to video consultations. Most patients undergoing ultrahypofractionated breast radiotherapy experience no toxicities or mild toxicities. These data suggest that adding a sequential boost following 26 Gy in 5 fractions to the whole breast is safe and does not lead to unacceptable 1-year toxicity. Patient satisfaction with ultrahypofractionated treatment and virtual consultations without video was high. However, less than half of patients may be open to virtual consultations and breast examination using video. [ FROM AUTHOR] Copyright of International Journal of Radiation Oncology, Biology, Physics is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

3.
International Journal of Radiation Oncology, Biology, Physics ; 114(3):S6-S6, 2022.
Article in English | Academic Search Complete | ID: covidwho-2036083

ABSTRACT

To report final results of a clinical trial of APBI using intensity modulated radiotherapy (IMRT) to deliver 27 Gy in 5 daily fractions following breast conserving surgery (BCS) prospectively designed to assess the efficacy and cosmetic outcomes of a 1-week, APBI regimen among women with early breast cancer. Women ≥ 50 years, with lymph node-negative, ER positive, HER-2 negative breast cancer or ductal carcinoma in situ (DCIS), ≤ 3cm diameter, following BCS with margins ≥ 2mm, and excellent or good baseline cosmesis received 27 Gy in 5 daily fractions to the seroma plus 1 cm CTV and 0.7 cm PTV margins. Clinical photographs, patient and provider cosmetic scores, breast fibrosis, telangiectasia and pain were collected prospectively, prior to RT and at 6 weeks, 1 and 2 years after RT. The primary endpoint was the proportion of women who retained Excellent or Good cosmesis at 2 years using the EORTC Cosmetic Rating System. Cosmetic failure was deterioration from Excellent or Good to Fair or Poor. A panel of 5 radiation oncologists independently assessed the cosmetic photographs. Secondary endpoints were rates and grades of breast fibrosis, telangiectasia, breast pain, ipsilateral breast tumor recurrence (IBRT), overall (OS), breast cancer-specific survival (BCSS) and subsequent mastectomy. Efficacy outcomes were assessed at clinic visits and by review of charts. ClinicalTrials.gov registration: NCT02681107. A total of 298 patients were treated between April 25, 2016, and October 31, 2019. At a median follow up of 48 months, the 4-year OS was 98.5% (95% CI 96.1% - 99.5%) and BCSS was 99.7% (95% CI 97.6% - 99.9%). The 4-year IBRT rate was 3.3% (95% CI 1.1% - 6.4%). There were 10 contralateral breast events for a 4-year rate of 3.9% (95% CI 2.2% - 6.9%). There were 10 ipsilateral and 6 contralateral mastectomies. Two patients died of unrelated causes prior to 2 years;79 patients declined in-clinic attendance due to COVID or competing comorbidities and 217 women had 2-year cosmetic photographs and clinical assessments performed. Consensus of the photo-panel cosmesis at baseline was: Excellent: n=116 (53%), Good: n=102 (47%), Fair: n=1 (0.5%) and Poor: n=0. Consensus overall cosmesis at 2 years was: Excellent: n= 141 (65%), Good: n=78 (35%), Fair: n=0 and Poor: n=0. Most patients had either improved (n=168;77%) or no change (n=43;20%) in cosmesis at 2-years. No patient had cosmetic failure but 6 (3%) had a change from Excellent to Good at 2 years. Most patients reported either no (79%) or mild (21%) pain, with no moderate or severe pain. Two patients (0.9%) had grade 2 fibrosis and 5 patients (2%) had visible telangiectasia that did not detract from overall cosmesis. APBI using 27 Gy in 5 fractions using a conformal IMRT technique, achieved excellent 2-year cosmesis with minimal toxicity. The IBRT risk was comparable to the contralateral new breast cancer risk and to local recurrence rates of recently published early breast cancer trials. [ FROM AUTHOR] Copyright of International Journal of Radiation Oncology, Biology, Physics is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

4.
Cells ; 11(14)2022 Jul 21.
Article in English | MEDLINE | ID: covidwho-2032863

ABSTRACT

Aplastic anemia (AA) is a rare and serious disorder of hematopoietic stem cells (HSCs) that results in the loss of blood cells due to the failure of the bone marrow (BM). Although BM transplantation is used to treat AA, its use is limited by donor availability. In this sense, mesenchymal stem cells (MSCs) can offer a novel therapeutic approach for AA. This is because the MSCs contribute to the hematopoietic niche organization through their repopulating. In our study, we used the human immature dental pulp stem cell (hIDPSC), an MSC-like cell, to explore an alternative therapeutic approach for AA. For this, isogenic C57BL/6 mice were exposed to total body irradiation (TBI) to induce the AA. After 48 h of TBI, the mice were intraperitoneally treated with hIDPSC. The immunohistochemistry analyses confirmed that the hIDPSCs migrated and grafted in the mouse bone marrow (BM) and spleen, providing rapid support to hematopoiesis recovery compared to the group exposed to radiation, but not to those treated with the cells as well as the hematological parameters. Six months after the last hIDPSC transplantation, the BM showed long-term stable hematopoiesis. Our data highlight the therapeutic plasticity and hematoprotective role of hIDPSC for AA and potentially for other hematopoietic failures.


Subject(s)
Anemia, Aplastic , Mesenchymal Stem Cells , Anemia, Aplastic/etiology , Anemia, Aplastic/therapy , Animals , Dental Pulp , Hematopoiesis , Humans , Mice , Mice, Inbred C57BL
5.
Particle & Particle Systems Characterization ; 2022.
Article in English | Web of Science | ID: covidwho-2030989

ABSTRACT

Gold nanoparticles (GNPs) are promising radiosensitizers for cancer radiotherapy. Moreover, they can be used in the same way for radiation processing and sterilization. Such application of GNPs is of practical interest since it may significantly reduce the dose load and expand the application of radiation treatment. In the present study, the high radiosensitization effect of GNPs in relation to viral particles is demonstrated for the first time. The preparations of tobacco mosaic virus (TMV) are used as an experimental model, insofar as this virus has the same properties as animal and human ones but is safe for humans. Irradiation with 45 kVp X-ray to the doses of 4 and 7 kGy leads to a decrease in the infectious activity of TMV virions up to 1.92- and 2.70-fold, respectively. At the same time, irradiation in the presence of 0.4 mg mL(-1) of 12 nm spherical GNPs increases the efficiency of virus inactivation up to 15- and 22-fold. The GNPs enhance both the damage to capsid protein due to the enhanced generation of reactive oxygen species and genome RNA due to the emission of secondary radiation. These results show the great prospects of the application of high-Z nanoparticles in radiation treatment.

6.
Mini Rev Med Chem ; 2022 Jan 04.
Article in English | MEDLINE | ID: covidwho-2029879

ABSTRACT

Widely consumed worldwide, Nigella sativa (NS) is a medicinal herb commonly used in various alternative medicine systems such as Unani and Tibb, Ayurveda, and Siddha. Recommended for regular use in Tibb-e-Nabwi (Prophetic Medicine), NS is considered one of the most notable forms of healing medicine in Islamic literature. Thymoquinone (TQ), the main component of the essential oil of NS, has been reported to have many properties such as antioxidant, anti-inflammatory, antiviral, and antineoplastic. Its chemical structure indicates antiviral potential against many viruses, including the hepatitis C virus, human immunodeficiency virus, and other coronavirus diseases. Interestingly, molecular docking studies have demonstrated that TQ can potentially inhibit the development of the coronavirus disease 2019 (COVID-19) by binding to the receptor site on the transmembrane serine proteinase 2 (the activator enzyme that attaches the virus to the cell). In addition, TQ has been shown to be effective against cancer cells due to its inhibitory effect by binding to the different regions of MDM2, according to the proposed molecular docking study. Detailed in this review is the origin of TQ, its significance in alternative medicine, pharmacological value, potential as a cancer anti-proliferative agent, use against the coronavirus disease 2019 (COVID-19), and treatment of other diseases.

7.
Frontiers of Environmental Science & Engineering ; 17(3), 2023.
Article in English | ProQuest Central | ID: covidwho-2027649

ABSTRACT

The COVID-19 pandemic remains ever prevalent and afflicting—partially because one of its transmission pathways is aerosol. With the widely used central air conditioning systems worldwide, indoor virus aerosols can rapidly migrate, thus resulting in rapid infection transmission. It is therefore important to install microbial aerosol treatment units in the air conditioning systems, and we herein investigated the possibility of combining such filtration with UV irradiation to address virus aerosols. Results showed that the removal efficiency of filtration towards f2 and MS2 phages depended on the type of commercial filter material and the filtration speed, with an optimal velocity of 5 cm/s for virus removal. Additionally, it was found that UV irradiation had a significant effect on inactivating viruses enriched on the surfaces of filter materials;MS2 phages had greater resistance to UV-C irradiation than f2 phages. The optimal inactivation time for UV-C irradiation was 30 min, with higher irradiation times presenting no substantial increase in inactivation rate. Moreover, excessive virus enrichment on the filters decreased the inactivation effect. Timely inactivation is therefore recommended. In general, the combined system involving filtration with UV-C irradiation demonstrated a significant removal effect on virus aerosols. Moreover, the system is simple and economical, making it convenient for widespread implementation in air-conditioning systems.

8.
Nanomaterials ; 12(17):3046, 2022.
Article in English | ProQuest Central | ID: covidwho-2023952

ABSTRACT

A new method has been developed to impart the antimicrobial activity of silver nanoparticles to resin substrates. A resin substrate immersed in an aqueous solution of silver nitrate was irradiated with gamma ray or high energy electron beams. Silver nanoparticles were successfully immobilized on the resin surface directly by chemical reactions induced by ionizing radiation. It was experimentally confirmed that various resin materials, such as acrylonitrile-butadiene-styrene, polyethylene, polypropylene, polyvinyl chloride, and polycarbonate, were applicable for this process. The effects of gamma ray or electron beam irradiation on resin substrates were almost negligible since the irradiation dose was equal or less than that used for sterilization. Despite the small amount of Ag loadings, the obtained samples showed high antibacterial and antiviral activities.

9.
Molecules ; 27(17):5535, 2022.
Article in English | ProQuest Central | ID: covidwho-2023947

ABSTRACT

As a promising metal-free photocatalyst, graphitic carbon nitride (g-C3N4) is still limited by insufficient visible light absorption and rapid recombination of photogenerated carriers, resulting in low photocatalytic activity. Here, we adjusted the microstructure of the pristine bulk-g-C3N4 (PCN) and further loaded silver (Ag) nanoparticles. Abundant Ag nanoparticles were grown on the thin-layer g-C3N4 nanosheets (CNNS), and the Ag nanoparticles decorated g-C3N4 nanosheets (Ag@CNNS) were successfully synthesized. The thin-layer nanosheet-like structure was not only beneficial for the loading of Ag nanoparticles but also for the adsorption and activation of reactants via exposing more active sites. Moreover, the surface plasmon resonance (SPR) effect induced by Ag nanoparticles enhanced the absorption of visible light by narrowing the band gap of the substrate. Meanwhile, the composite band structure effectively promoted the separation and transfer of carriers. Benefiting from these merits, the Ag@CNNS reached a superior hydrogen peroxide (H2O2) yield of 120.53 μmol/g/h under visible light irradiation in pure water (about 8.0 times higher than that of PCN), significantly surpassing most previous reports. The design method of manipulating the microstructure of the catalyst combined with the modification of metal nanoparticles provides a new idea for the rational development and application of efficient photocatalysts.

10.
Molecules ; 27(16):5058, 2022.
Article in English | ProQuest Central | ID: covidwho-2023931

ABSTRACT

This work is devoted to the investigation of heterobimetallic Ru(II) complexes as photosensitizers for room-temperature photoactivated In2O3-based gas sensors. Nanocrystalline In2O3 was synthesized by the chemical precipitation method. The obtained In2O3 matrix has a single-phase bixbyite structure with an average grain size of 13–14 nm and a specific surface area of 72 ± 3 m2/g. The synthesis of new ditope ligands with different coordination centers, their ruthenium complexes, and the preparation of heterobimetallic complexes with various cations of heavy and transition metals (Ag+, Pb2+, or Cu2+) is reported. The heterobimetallic Ru(II) complexes were deposited onto the surface of the In2O3 matrix by impregnation. The obtained hybrid materials were characterized by X-ray fluorescent analysis, FTIR spectroscopy, and optical absorption spectroscopy. The elemental distribution on the hybrids was characterized by energy-dispersive X-ray spectroscopy (EDS) mapping. The gas sensor properties were investigated toward NO2, NO, and NH3 at room temperature under periodic blue LED irradiation. It was identified that the nature of the second binding cation in Ru(II) heterobimetallic complexes can influence the selectivity toward different gases. Thus, the maximum sensor signal for oxidizing gases (NO2, NO) was obtained for hybrids containing Ag+ or Pb2+ cations while the presence of Cu2+ cation results in the highest and reversible sensor response toward ammonia. This may be due to the specific adsorption of NH3 molecules on Cu2+ cations. On the other hand, Cu2+ ions are proposed to be active sites for the reduction of nitrogen oxides to N2. This fact leads to a significant decrease in the sensor response toward NO2 and NO gases.

11.
Catalysts ; 12(8):856, 2022.
Article in English | ProQuest Central | ID: covidwho-2023199

ABSTRACT

Legionella pneumophila (L. pneumophila) is the causative agent of Legionnaires’ disease and Pontiac fever, collectively known as legionellosis. L. pneumophila infection occurs through inhalation of contaminated aerosols from water systems in workplaces and institutions. The development of disinfectants that can eliminate L. pneumophila in such water systems without evacuating people is needed to prevent the spread of L. pneumophila. Photocatalysts are attractive disinfectants that do not harm human health. In particular, the TiO2 photocatalyst kills L. pneumophila under various conditions, but its mode of action is unknown. Here, we confirmed the high performance of TiO2 photocatalyst containing PtO2 via the degradation of methylene blue (half-value period: 19.2 min) and bactericidal activity against Escherichia coli (half-value period: 15.1 min) in water. Using transmission electron microscopy, we demonstrate that the disinfection of L. pneumophila (half-value period: 6.7 min) by TiO2 photocatalyst in water is accompanied by remarkable cellular membrane and internal damage to L. pneumophila. Assays with limulus amebocyte lysate and silver staining showed the release of endotoxin from L. pneumophila due to membrane damage and photocatalytic degradation of this endotoxin. This is the first study to demonstrate the disinfection mechanisms of TiO2 photocatalyst, namely, via morphological changes and membrane damage of L. pneumophila. Our results suggest that TiO2 photocatalyst might be effective in controlling the spread of L. pneumophila.

12.
Catalysts ; 12(8):829, 2022.
Article in English | ProQuest Central | ID: covidwho-2023197

ABSTRACT

The transmission of pathogens via surfaces poses a major health problem, particularly in hospital environments. Antimicrobial surfaces can interrupt the path of spread, while photocatalytically active titanium dioxide (TiO2) nanoparticles have emerged as an additive for creating antimicrobial materials. Irradiation of such particles with ultraviolet (UV) light leads to the formation of reactive oxygen species that can inactivate bacteria. The aim of this research was to incorporate TiO2 nanoparticles into a cellulose-reinforced melamine-formaldehyde resin (MF) to obtain a photocatalytic antimicrobial thermoset, to be used, for example, for device enclosures or tableware. To this end, composites of MF with 5, 10, 15, and 20 wt% TiO2 were produced by ultrasonication and hot pressing. The incorporation of TiO2 resulted in a small decrease in tensile strength and little to no decrease in Shore D hardness, but a statistically significant decrease in the water contact angle. After 48 h of UV irradiation, a statistically significant decrease in tensile strength for samples with 0 and 10 wt% TiO2 was measured but with no statistically significant differences in Shore D hardness, although a statistically significant increase in surface hydrophilicity was measured. Accelerated methylene blue (MB) degradation was measured during a further 2.5 h of UV irradiation and MB concentrations of 12% or less could be achieved. Samples containing 0, 10, and 20 wt% TiO2 were investigated for long-term UV stability and antimicrobial activity. Fourier-transform infrared spectroscopy revealed no changes in the chemical structure of the polymer, due to the incorporation of TiO2, but changes were detected after 500 h of irradiation, indicating material degradation. Specimens pre-irradiated with UV for 48 h showed a total reduction in Escherichia coli when exposed to UV irradiation.

13.
Food Control ; : 109340, 2022.
Article in English | ScienceDirect | ID: covidwho-2007702

ABSTRACT

The detection of infectious SARS-CoV-2 in food and food packaging associated with the cold chain has raised concerns about the possible transmission pathway of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in foods transported through cold-chain logistics and the need for novel decontamination strategies. In this study, the effect of electron beam (E-beam) irradiation on the inactivation of two SARS-CoV-2surrogate, viruses porcine epidemic diarrhea virus (PEDV) and porcine transmissible gastroenteritis virus (TGEV), in culture medium and food substrate, and on food substrate were investigated. The causes of virus inactivation were also investigated by transmission electron microscopy (TEM) and Quantitative Real-time PCR (QRT-PCR). Samples packed inside and outside, including virus-inoculated large yellow croaker and virus suspensions, were irradiated with E-beam irradiation (2, 4, 6, 8, 10 kGy) under refrigerated (0 °C)and frozen (−18 °C) conditions. The titers of both viruses in suspension and fish decreased significantly (P < 0.05) with increasing doses of E-beam irradiation. The maximum D10 value of both viruses in suspension and fish was 1.24 kGy. E-beam irradiation at doses below 10 kGy was found to destroy the spike proteins of both SARS-CoV-2 surrogate viruses by transmission electron microscopy (TEM) and negative staining of thin-sectioned specimens, rendering them uninfectious. E-beam irradiation at doses greater than 10 kGy was also found to degrade viral genomic RNA by qRT-PCR. There were no significant differences in color, pH, TVB-N, TBARS, and sensory properties of irradiated fish samples at doses below 10 kGy. These findings suggested that E-beam irradiation has the potential to be developed as an efficient non-thermal treatment to reduce SARS-CoV-2 contamination in foods transported through cold chain foods to reduce the risk of SARS-CoV-2 infection in humans through the cold chain.

14.
Am J Infect Control ; 50(8): 947-953, 2022 08.
Article in English | MEDLINE | ID: covidwho-2000206

ABSTRACT

BACKGROUND: Ultraviolet germicidal irradiation (UVGI) technologies have emerged as a promising adjunct to manual cleaning, however, their potential to shorten cleaning times remains unexplored. METHODS: A <10-minute disinfection procedure was developed using a robotic UVGI platform. The efficacy and time to perform the UVGI procedure in a CT scan treatment room was compared with current protocols involving manual disinfection using biocides. For each intervention, environmental samples were taken at 12 locations in the room before and after disinfection on seven distinct occasions. RESULTS: The mean UVC dose at each sample location was found to be 13.01 ± 4.36 mJ/cm2, which exceeded published UVC thresholds for achieving log reductions of many common pathogens. Significant reductions in microbial burden were measured after both UVGI (P≤.001) and manual cleaning (P≤.05) conditions, with the UVGI procedure revealing the largest effect size (r = 0.603). DISCUSSION: These results support the hypothesis that automated deployments of UVGI technology can lead to germicidal performance that is comparable with, and potentially better than, current manual cleaning practices. CONCLUSIONS: Our findings provide early evidence that the incorporation of automated UVGI procedures into cleaning workflow could reduce turnaround times in radiology, and potentially other hospital settings.


Subject(s)
Radiology , Robotics , Disinfection/methods , Hospitals , Humans , Ultraviolet Rays
15.
Medical Devices: Evidence and Research ; 15:277-283, 2022.
Article in English | EMBASE | ID: covidwho-1997376

ABSTRACT

Background: Cold plasma has many characteristics that allow for effective wound healing. Due to its efficacy, we have applied it in treating patients with severe Covid-19 who have soft tissue skin lesions and diseases including burns, pressure ulcers, shingles, and contact or atopic dermatitis. This study aims to assess the general characteristics of Covid-19 patients with soft tissue lesions and to conduct a fundamental evaluation of the efficacy of cold plasmamed beams in treating soft tissue wounds in patients with severe Covid-19. Methods: This prospective study was conducted on 20 severe Covid-19 patients with soft tissue lesions at the Intensive Care Center for Covid-19 of Hue Central Hospital in Ho Chi Minh City from September 25 to November 11, 2021. These patients was performed cold plasma irradiation at any stage of wound progression, including new injuries and chronic wounds. Results: Among 915 severe Covid-19 patients treated at our center, 20 patients had soft tissue lesions. Grade I, II, and III pressure ulcers accounted for 70% of the 20 cases of soft tissue lesions and 1.53% of the total patients at the time of the survey. Pressure ulcers were present in only 0.55% of patients (5/915 patients). Eleven out of 20 patients (55.0%) had lesions before admission, and 9 (45.0%) had lesions that appeared after admission. After 14 days of treatment, 14/20 patients had complete epithelialization (70%), and in 18/20 patients, wound exudation had ceased. The wounds became painless;after 3 weeks, the rashes had completely disappeared. Conclusion: The study emphasizes that irradiation with cold plasma contributes to the wound healing process.

16.
Cytotherapy ; 24(5):S164, 2022.
Article in English | EMBASE | ID: covidwho-1996731

ABSTRACT

Background & Aim: Mill Creek’s human platelet lysate (hPL) is produced using expired human platelets obtained from accredited blood banks in the United States. These platelets were originally intended for use in patient transfusion. The safety of platelets used in transfusion is managed by the U.S. Food & Drug Administration (FDA), as well as the American Association of Blood Banks (AABB). These organizations set standards, including testing for transmissible diseases. The United States record for blood safety is well established, with extremely low rates of disease transmission, making the platelet units used for hPL manufacture low risk. However, over the past few decades, the number of emerging infectious diseases that spread to people has increased. Even though transmission of Covid-19 and other potential emergent pathogens via blood transfusion has not been documented, adventitious agents remain a concern. For that reason, pathogen reduction processes are necessary to improve the safety profile of blood-derived products used in the manufacture of cellbased therapies. One of these processes is the pathogen reduction through gamma irradiation. Methods, Results & Conclusion: Previously, we validated a process to produce gamma irradiated human platelet lysate. To be able to release the gamma irradiated product as a pathogen reduced product, we additionally performed a viral clearance study, which determined the efficacy of the process to actually reduce a potential viral contaminant. Here, we present the results obtained from the viral clearance study performed on our gamma irradiated hPL, and from the expansion of different types of therapeutic cells using our gamma irradiated hPLs, which showed unprecedented levels of product quality and efficiency. Our products are a game changer for the growing market of cell base therapies bioprocessing and manufacturing.

17.
Physica Medica ; 94:S24, 2022.
Article in English | EMBASE | ID: covidwho-1996709

ABSTRACT

Background and Aims: Passive antibody administration through convalescent plasma has shown benefit in treating COVID-19 in the early stages of the disease in patients >65 years old, and in other viral outbreaks. A practical, rapid method to sterilize convalescent plasma while also maintaining antibody function would be valuable for safe treatment in future viral pandemics. Plasma sterilization by irradiation requires kGy of dose to deactivate bacteria and viruses of concern. Conventional lab-based irradiators would require days to reach such doses, while ultra-high dose rate irradiation (FLASH) would require minutes. We present a proof-of-concept on sterilizing plasma with 25 kGy in approximately 3 minutes without damaging the antibodies in the plasma. Methods: A Varian Trilogy LINAC was configured for 16 MeV FLASH electron irradiation. Frozen aliquots of convalescent plasma from patients with COVID-19 were placed in a 3D printed holder submerged in liquid aiming to preserve sample temperature (RT, 4°C or –20°C). The number of pulses was estimated with EBT-XD film. Samples were irradiated with a dose of 25 kGy in ~33,330 pulses over 185 seconds. Antibody binding against the receptor-binding domain (RBD) of the S1 region of SARS-CoV-2 was measured by ELISA pre- and post-irradiation. Results: Frozen plasma aliquots from 10 COVID-19 convalescent plasma donors were irradiated in frozen state to 25 kGy dose. IgG antibody binding against SARS-CoV-2 RBD after irradiation remained at 90.8% of non-irradiated samples (Fig. 1;OD 1.25 vs. 1.36, p<0.0003). (Figure Presented) Fig. 1 ( O034). Plasma aliquots from 10 convalescent plasma samples were irradiated at sterilizing 25-kGy doses. IgG binding to SARS-CoV-2 RBD antigen by ELISA is 90.8% compared to unirradiated. Conclusions: FLASH irradiation allows for rapid sterilization of blood plasma from potential pathogens while largely preserving antibody binding function and specificity.

18.
International Journal of Radiation Oncology*Biology*Physics ; 114(1):A11-A13, 2022.
Article in English | EMBASE | ID: covidwho-1984266
19.
IEEE International Instrumentation and Measurement Technology Conference (I2MTC) ; 2021.
Article in English | Web of Science | ID: covidwho-1978392

ABSTRACT

LED lighting is becoming increasingly pervasive in many areas ranging from ambient lighting, up to applications such as microscope illumination, UV-LED curing and, UV disinfection for air, surfaces, and water. Irradiance uniformity is often a fundamental parameter for guiding the design, comparison, and optimization of the illuminator. To this end, many methods and procedures have been proposed to guide the arrangement of the LED sources, as well as to guide the design of ad-hoc lenses. Nevertheless, there are many applications in which it is important to be able to consider other aspects as well as the uniformity of the irradiance. For this purpose, we propose both a method that allows calculating the irradiance generated by the used LED sources and, performance indicators for guiding the design and comparing different optical layouts.

20.
International Conference on Intelligent Systems and Networks, ICISN 2022 ; 471 LNNS:83-91, 2022.
Article in English | Scopus | ID: covidwho-1971630

ABSTRACT

N95 disposable respirator masks are of particular importance to the Covid-19 pandemic. The high cost and limited supply of N95 disposable respirators promote research and safe and effective methods of reusing medical masks. The CDC of USA has announced that ultraviolet (UVC) irradiation inactivates SARS-CoV-2, virus, and other microorganisms known to culture on N95, as well as the results affecting mask fit and filterability. In this study, we analyze and evaluate the pathogen inactivation mechanism and the performance of respirators after treatment and perfect the method of ultraviolet irradiation (UVC) to help inactivate of SARS-CoV-2. At the same time, the research team successfully designed, fabricated and tested a semi-automatic system with UVC capacity 0.15 mW/cm2 at 220 nm that inactivated SARS-CoV-2 (3 log reduction) substances analogues of viruses, and other microorganisms grown on N95. The research results aim to commercialize the system technology (1) to inactivate the SARS-CoV-2 virus through the our application of UVC irradiation at the appropriate wavelength and effective dose, and (2) maintain the suitability and N95 filter rate. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

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