Comparison of Sputum Treated with Power Ultrasound and Routine NALC-NaOH Methods for Mycobacterial Culture: A Prospective Study

Mycobacterial culture remains the gold standard for the diagnosis of active tuberculosis. However, an appropriate digestion and decontamination method is essential for the effective recovery of tubercle bacilli in culture. The study was designed to compare the efficacy of sputum treated with power ultrasound (PU) and routine NALC-NaOH methods for mycobacterial culture from clinically suspected cases of pulmonary tuberculosis. To evaluate the PU and routine NALC-NaOH methods, sputum specimens (n = 597) were studied (culturing on MGIT 960), and the performances were compared. Of the 597 samples, 89 (14.91%) sputum samples treated with the NaOH-NALC method were mycobacterial culture positive, including Mycobacterium tuberculosis (M.TB; n = 77, 12.90%) and nontuberculous mycobacteria (NTM; n = 12, 2.01%). One hundred and ten (18.43%) sputum samples treated with the PU method were culture positive, including M.TB (n = 87, 14.57%) and NTM (n = 23, 3.85%). The PU method detected 10 additional cases of M.TB and 11 additional cases of NTM when compared to the NALC-NaOH method. Statistical analysis showed that a significant difference was found in the culture-positive ratio of M.TB and NTM between the two method groups (p < 0.05). Compared with that of the NALC-NaOH method (8.04%), sputum treated with PU method (4.86%) had a significantly lower contamination rate (p < 0.05). In conclusion, our data indicate that, compared with the NALC-NaOH method, the PU method is a rapid and effective approach for mycobacterial culture when detecting active TB. However, its accurate mechanism has not been well addressed, and further investigation is still required.

Evaluation of the Microbiological Effectiveness of Three Accessible Mask Decontamination Methods and Their Impact on Filtration, Air Permeability and Physicochemical Properties

The need to secure public health and mitigate the environmental impact associated with the massified use of respiratory protective devices (RPD) has been raising awareness for the safe reuse of decontaminated masks by individuals and organizations. Among the decontamination treatments proposed, in this work, three methods with the potential to be adopted by households and organizations of different sizes were analysed: contact with nebulized hydrogen peroxide (H2O2); immersion in commercial bleach (NaClO) (sodium hypochlorite, 0.1% p/v); and contact with steam in microwave steam-sanitizing bags (steam bag). Their decontamination effectiveness was assessed using reference microorganisms following international standards (issued by ISO and FDA). Furthermore, the impact on filtration efficiency, air permeability and several physicochemical and structural characteristics of the masks, were evaluated for untreated masks and after 1, 5 and 10 cycles of treatment. Three types of RPD were analysed: surgical, KN95, and cloth masks. Results demonstrated that the H2O2 protocol sterilized KN95 and surgical masks (reduction of >6 log10 CFUs) and disinfected cloth masks (reduction of >3 log10 CFUs). The NaClO protocol sterilized surgical masks, and disinfected KN95 and cloth masks. Steam bags sterilized KN95 and disinfected surgical and cloth masks. No relevant impact was observed on filtration efficiency.

Cleaning effects of decontamination methods on clinically failed TiUnite implants and their impacts on surface roughness and chemistry: An in vitro pilot study

PURPOSE

To evaluate the in vitro cleaning effects of different decontamination methods and their impacts on surface characteristics using clinically failed TiUnite implants (Nobel Biocare, Kloten, Switzerland).

MATERIALS AND METHODS

Thirty clinically failed TiUnite implants were treated using different decontamination methods. Group 1 (control group) received physiological saline irrigation; Group 2 underwent erythritol powder air polishing (AIRFLOW Master Piezon, EMS Dental, Nyon, Switzerland); Group 3 was treated with erythritol powder air polishing with ethylenediaminetetraacetic acid brushing (FileRite PRC, Pulpdent, Watertown, MA, USA); Group 4 received ultrasonic scaling with polyetheretherketone tips (EMS Dental); Group 5 underwent ultrasonic scaling with polyetheretherketone tips with ethylenediaminetetraacetic acid; and Group 6 was treated with a combination of ultrasonic scaling with polyetheretherketone tips, erythritol powder air polishing and ethylenediaminetetraacetic acid. Surface cleaning effects, quantified by relative contaminated area reduction and visual analogue scale score, as well as surface roughness and chemistry, were assessed after decontamination. The cleaning effects of each decontamination method were also compared between TiUnite and SLA (sandblasted, large-grit acid-etched; Straumann, Basel, Switzerland) implants.

RESULTS

Group 6 showed the highest relative contaminated area reduction (stereoscopic microscopy 83.92%, scanning electron microscopy 96.40%), visual analogue scale score (2.83) and reduction in surface roughness (thread bottom -0.78 μm, tip -1.35 μm), as well as an almost maximal decrease in the proportion of carbon (thread bottom -12.33%, tip -8.77%) and increase in that of titanium (thread bottom 13.71%, tip 10.73%). Polyetheretherketone remnants were observed in Groups 4 and 5 but appeared to be reduced in Group 6. When comparing the outcomes with those for SLA implants, no significant differences were found.

CONCLUSION

Within the limitations of the present study, the combination of ultrasonic scaling with polyetheretherketone tips, erythritol powder air polishing and ethylenediaminetetraacetic brushing achieved reasonable cleaning effects. The original surface modification did not seem to have any impact on the decontamination results for any of the methods examined.

Mycotoxins along the tea supply chain: A dark side of an ancient and high valued aromatic beverage

ABSTRACTSTea (Camellia sinensis L.) is a high valued beverage worldwide since ancient times; more than three billion cups of tea are consumed each day. Leaf extracts of the plant are used for food preservation, cosmetics, and medicinal purposes. Nevertheless, tea contaminated with mycotoxins poses a serious health threat to humans. Mycotoxin production by tea fungi is induced by a variety of factors, including poor processing methods and environmental factors such as high temperature and humidity. This review summarizes the studies published to date on mycotoxin prevalence, toxicity, the effects of climate change on mycotoxin production, and the methods used to detect and decontaminate tea mycotoxins. While many investigations in this domain have been carried out on the prevalence of aflatoxins and ochratoxins in black, green, pu-erh, and herbal teas, much less information is available on zearalenone, fumonisins, and Alternaria toxins. Mycotoxins in teas were detected using several methods; the most commonly used being the High-Performance Liquid Chromatography (HPLC) with fluorescence detection, followed by HPLC with tandem mass spectrometry, gas chromatography and enzyme-linked immunosorbent assay. Further, mycotoxins decontamination methods for teas included physical, chemical, and biological methods, with physical methods being most prevalent. Finally, research gaps and future directions have also been discussed.

Shoe soles as a potential vector for pathogen transmission: a systematic review

Shoe soles are possible vectors for infectious diseases. Although studies have been performed to assess the prevalence of infectious pathogens on shoe soles and decontamination techniques, no systematic review has ever occurred. The aim of this study was to perform a systematic review of the literature to determine the prevalence of infectious agents on shoe bottoms and possible decontamination strategies. Three electronic bibliographic databases were searched using a predefined search strategy evaluating prevalence of infectious pathogens on shoe bottoms and decontamination strategies. Quality assessment was performed independently by two reviews with disagreements resolved by consensus. Thirteen studies were identified that supported the hypothesis that shoe soles are a vector for infectious pathogens. Methicillin-resistant Staphylococcus aureus, Clostridium difficile and multidrug-resistant Gram-negative species among other pathogens were documented on shoe bottoms in the health care setting, in the community and among food workers. Fifteen studies were identified that investigated decontamination strategies for shoe soles. A number of decontamination strategies have been studied of which none have been shown to be consistently successful at disinfecting shoe soles. In conclusion, a high prevalence of microbiological pathogens was identified from shoe soles studied in the health care, community and animal worker setting. An effective decontamination strategy for shoe soles was not identified. Studies are needed to assess the potential for contaminated shoes to contribute to the transmission of infectious pathogens.