Impact of COVID-19 Pandemic on the National PPM Tuberculosis Control Project in Korea: the Korean PPM Monitoring Database between July 2019 and June 2020

Background@#The coronavirus disease 2019 (COVID-19) pandemic caused disruptions to healthcare systems and endangered the control and prevention of tuberculosis (TB). We investigated the nationwide effects of COVID-19 on the national Public-Private Mix (PPM) TB control project in Korea, using monitoring indicators from the Korean PPM monitoring database. @*Methods@#The Korean PPM monitoring database includes data from patients registered at PPM hospitals throughout the country. Data of six monitoring indicators for active TB cases updated between July 2019 and June 2020 were collected. The data of each cohort throughout the country and in Daegu-Gyeongbuk, Seoul Metropolitan Area, and Jeonnam-Jeonbuk were collated to provide nationwide data. The data were compared using the χ 2 test for trend to evaluate quarterly trends of each monitoring indicator at the national level and in the prespecified regions. @*Results@#Test coverages of sputum smear (P = 0.622) and culture (P = 0.815), drug susceptibility test (P = 0.750), and adherence rate to initial standard treatment (P = 0.901) at the national level were not significantly different during the study period. The rate of loss to follow-up among TB cases at the national level was not significantly different (P = 0.088) however, the treatment success rate among the smear-positive drug-susceptible pulmonary TB cohort at the national level significantly decreased, from 90.6% to 84.1% (P < 0.001). Treatment success rate in the Seoul metropolitan area also significantly decreased during the study period, from 89.4% to 84.5% (P = 0.006). @*Conclusion@#Our study showed that initial TB management during the COVID-19 pandemic was properly administered under the PPM project in Korea. However, our study cannot confirm or conclude a decreased treatment success rate after the COVID-19 pandemic due to limited data.

Lateral Geniculate Body Evoked Potentials Elicited by Visual and Electrical Stimulation

PURPOSE: Blind individuals who have photoreceptor loss are known to perceive phosphenes with electrical stimulation of their remaining retinal ganglion cells. We proposed that implantable lateral geniculate body (LGB) stimulus electrode arrays could be used to generate phosphene vision. We attempted to refine the basic reference of the electrical evoked potentials (EEPs) elicited by microelectrical stimulations of the optic nerve, optic tract and LGB of a domestic pig, and then compared it to visual evoked potentials (VEPs) elicited by short-flash stimuli. METHODS: For visual function measurement, VEPs in response to short-flash stimuli on the left eye of the domestic pig were assessed over the visual cortex at position Oz with the reference electrode at Fz. After anesthesia, linearly configured platinum wire electrodes were inserted into the optic nerve, optic track and LGB. To determine the optimal stimulus current, EEPs were recorded repeatedly with controlling the pulse and power. The threshold of current and charge density to elicit EEPs at 0.3 ms pulse duration was about ±10 microA. RESULTS: Our experimental results showed that visual cortex activity can be effectively evoked by stimulation of the optic nerve, optic tract and LGB using penetrating electrodes. The latency of P1 was more shortened as the electrical stimulation was closer to LGB. The EEPs of two-channel in the visual cortex demonstrated a similar pattern with stimulation of different spots of the stimulating electrodes. We found that the LGB-stimulated EEP pattern was very similar to the simultaneously generated VEP on the control side, although implicit time deferred. CONCLUSIONS: EEPs and VEPs derived from visual-system stimulation were compared. The LGB-stimulated EEP wave demonstrated a similar pattern to the VEP waveform except implicit time, indicating prosthetic-based electrical stimulation of the LGB could be utilized for the blind to perceive vision of phosphenes.

House-plant placement for indoor air purification and health benefits on asthmatics

OBJECTIVES: Some plants were placed in indoor locations frequented by asthmatics in order to evaluate the quality of indoor air and examine the health benefits to asthmatics. METHODS: The present study classified the participants into two groups: households of continuation and households of withdrawal by a quasi-experimental design. The households of continuation spent the two observation terms with indoor plants, whereas the households of withdrawal passed the former observation terms with indoor plants and went through the latter observation term without any indoor plants. RESULTS: The household of continuation showed a continual decrease in the indoor concentrations of volatile organic compounds (VOCs) during the entire observation period, but the household of withdrawal performed an increase in the indoor concentrations of VOCs, except formaldehyde and toluene during the latter observation term after the decrease during the former observation term. Peak expiratory flow rate (PEFR) increased in the households of continuation with the value of 13.9 L/min in the morning and 20.6 L/ min in the evening, but decreased in the households of withdrawal with the value of -24.7 L/min in the morning and -30.2 L/min in the evening in the first experimental season. All of the households exhibited a decrease in the value of PEFR in the second experimental season. CONCLUSIONS: Limitations to the generalizability of findings regarding the presence of plants indoors can be seen as a more general expression of such a benefit of human-environment relations.

Exposure and Toxicity Assessment of Ultrafine Particles from Nearby Traffic in Urban Air in Seoul, Korea

OBJECTIVES: We investigated the particle mass size distribution and chemical properties of air pollution particulate matter (PM) in the urban area and its capacity to induce cytotoxicity in human bronchial epithelial (BEAS-2B) cells. METHODS: To characterize the mass size distributions and chemical concentrations associated with urban PM, PM samples were collected by a 10-stage Micro-Orifice Uniform Deposit Impactor close to nearby traffic in an urban area from December 2007 to December 2009. PM samples for in vitro cytotoxicity testing were collected by a mini-volume air sampler with PM10 and PM2.5 inlets. RESULTS: The PM size distributions were bi-modal, peaking at 0.18 to 0.32 and 1.8 to 3.2 microm. The mass concentrations of the metals in fine particles (0.1 to 1.8 microm) accounted for 45.6 to 80.4% of the mass concentrations of metals in PM10. The mass proportions of fine particles of the pollutants related to traffic emission, lead (80.4%), cadmium (69.0%), and chromium (63.8%) were higher than those of other metals. Iron was the dominant transition metal in the particles, accounting for 64.3% of the PM10 mass in all the samples. We observed PM concentration-dependent cytotoxic effects on BEAS-2B cells. CONCLUSIONS: We found that exposure to PM2.5 and PM10 from a nearby traffic area induced significant increases in protein expression of inflammatory cytokines (IL-6 and IL-8). The cell death rate and release of cytokines in response to the PM2.5 treatment were higher than those with PM10. The combined results support the hypothesis that ultrafine particles from vehicular sources can induce inflammatory responses related to environmental respiratory injury.

Corrigendum: Health Risks Assessments in Children for Phthalates Exposure Associated with Childcare Facilities and Indoor Playgrounds

In Table 6, the unit concentration of phthalates was not correctly indicated.

Health Risk Assessment of Lead Ingestion Exposure by Particle Sizes in Crumb Rubber on Artificial Turf Considering Bioavailability

OBJECTIVES: The purpose of this study was to assess the risk of ingestion exposure of lead by particle sizes of crumb rubber in artificial turf filling material with consideration of bioavailability. METHODS: This study estimated the ingestion exposure by particle sizes (more than 250 um or less than 250 um) focusing on recyclable ethylene propylene diene monomer crumb rubber being used as artificial turf filling. Analysis on crumb rubber was conducted using body ingestion exposure estimate method in which total content test method, acid extraction method and digestion extraction method are reflected. Bioavailability which is a calibrating factor was reflected in ingestion exposure estimate method and applied in exposure assessment and risk assessment. Two methods using acid extraction and digestion extraction concentration were compared and evaluated. RESULTS: As a result of the ingestion exposure of crumb rubber material, the average lead exposure amount to the digestion extraction result among crumb rubber was calculated to be 1.56x10(-4) mg/kg-day for low grade elementary school students and 4.87x10(-5) mg/kg-day for middle and high school students in 250 um or less particle size, and that to the acid extraction result was higher than the digestion extraction result. Results of digestion extraction and acid extraction showed that the hazard quotient was estimated by about over 2 times more in particle size of lower than 250 um than in higher than 250 um. There was a case of an elementary school student in which the hazard quotient exceeded 0.1. CONCLUSIONS: Results of this study confirm that the exposure of lead ingestion and risk level increases as the particle size of crumb rubber gets smaller.

Analysis of the BRAF(V600E) Mutation in Thyroid Nodules: the Preoperative Diagnostic Role of Fine-needle Aspiration Biopsy for Patients with Papillary Thyroid Cancer and Its Impact on Patient Care

PURPOSE: We wanted to evaluate the frequency of BRAF(V600E) mutations on the preoperative fine-needle aspiration biopsies (FNAB) of thyroid nodules and the effect of this on the accuracy of diagnosing papillary thyroid cancer (PTC). We also wanted to evaluate the influence of BRAF(V600E) analysis on patient care. MATERIALS AND METHODS: The results of cytology and BRAF(V600E) mutation analysis of 190 thyroid nodules were retrospectively reviewed. The results of the cytology and BRAF(V600E) analysis were compared with the histopathological diagnosis for the surgically confirmed cases, and we calculated the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and the diagnostic accuracy of FNAB and combining the modalities of FNAB and BRAF(V600E) mutation. The frequency of BRAF(V600E) mutation according to age and the influence of BRAF(V600E) analysis on patient care were studied. The nodule size was compared between the malignant and other categories of BRAF(V600E) positive nodules. RESULTS: Seventy four percent of the PTC were BRAF(V600E) positive. BRAF(V600E) analysis increased the sensitivity, NPP and diagnostic accuracy of FNAB. Fifty percent of the BRAF(V600E) positive nodules with other than malignant cytology received surgery and these were confirmed to be PTC. The frequency of BRAF(V600E) mutation increased with age, which was statistically significant. There was a statistically significant difference in the nodule size between the cytologically malignant nodules and the other nodules. CONCLUSION: BRAF(V600E) analysis increased the diagnostic accuracy of FNAB and it should be considered as being complementary to cytological analysis. The frequency of the BRAF(V600E) mutation increased with age. The size of the malignant nodules was larger than that of the benign nodules.

Health Risks Assessment in Children for Phthalate Exposure Associated with Childcare Facilities and Indoor Playgrounds

OBJECTIVES: This study assessed the health risks for children exposed to phthalate through several pathways including house dust, surface wipes and hand wipes in child facilities and indoor playgrounds. METHODS: The indoor samples were collected from various children's facilities (40 playrooms, 42 daycare centers, 44 kindergartens, and 42 indoor-playgrounds) in both summer (Jul-Sep, 2007) and winter (Jan-Feb, 2008). Hazard index (HI) was estimated for the non-carcinogens and the examined phthalates were diethylhexyl phthalate (DEHP), diethyl phthalate (DEP), dibutyl-n-butyl phthalate (DnBP), and butylbenzyl phthalate (BBzP). The present study examined these four kinds of samples, i.e., indoor dust, surface wipes of product and hand wipes. RESULTS: Among the phthalates, the detection rates of DEHP were 98% in dust samples, 100% in surface wipe samples, and 95% in hand wipe samples. In this study, phthalate levels obtained from floor dust, product surface and children's hand wipe samples were similar to or slightly less compared to previous studies. The 50th and 95th percentile value of child-sensitive materials did not exceed 1 (HI) for all subjects in all facilities. CONCLUSIONS: For DEHP, DnBP and BBzP their detection rates through multi-routes were high and their risk based on health risk assessment was also observed to be acceptable. This study suggested that ingestion and dermal exposure could be the most important pathway of phthalates besides digestion through food.

Evaluating a Thrombosed Azygous Vein Aneurysm Combined with Pulmonary Arterial Thromboembolism by ECG-Gated Multidetector CT: a Case Report

Azygous vein aneurysm is a rare congenital lesion that needs to be differentiated from mediastinal mass lesions. Although almost of these anomalies are asymptomatic lesions, we experienced an interesting case in which a thrombus within an azygous vein aneurysm in a 75-year-old woman caused pulmonary thromboembolism. The patient was managed by medical treatment for one month and then the thrombus within both the azygous vein aneurysm and the pulmonary arteries completely resolved.

Photocatalytic antifungal activity against candida albicans by TiO2 coated acrylic resin denture base / 대한치과보철학회지

Statement of problem. Proliferation of Candida albicans is primarily within the plaque on the fitting surface of the denture rather than on the inflamed mucosa. Consequently, the treatment of the denture is equally important as treatment of the tissue. Cleansing and disinfection should be efficiently carried-out as the organisms can penetrate into the voids of the acrylic resin and grow in them, from which they can continue to infect and reinfect bearing tissues. Purpose. The purpose of this study was to evaluate the applicability of photocatalytic reaction to eliminate Candida albicans from acrylic resin denture base, and to investigate the antifungal effect with various UVA illumination time. Materials and Methods. The specimens were cured by the conventional method following the manufacturer's instruction using thermal polymerized denture base resin (Vertex RS; Dentimex, Netherlands). TiO2 photocatalyst sol(LT), which is able to be coated at normal temperature, was made from the Ti-alkoxide progenitor. The XRD patterns, TEM images and nitrogen absorption ability of the TiO2 photocatalyst sol(LT) were compared with the commercial TiO2 photocatalyst P-25. The experimental specimens were coated with the mixture of the TiO2 photocatalyst sol(LT) and binder material (silane) using dip-coater, and uncoated resin plates were used as the control group. Crystallinity of TiO2 of the specimen was tested by the XRD. Size, shape and chemical compositions were also analyzed using the FE-SEM/EDS. The angle and methylene blue degradation efficiency were measured for evaluating the photocatalytic activity of the TiO2 film. Finally, the antifungal activity of the specimen was tested. Candida albicans KCTC 7629(1 ml, initial concentration 105cells/ml) were applied to the experiment and control group specimens and subsequently two UVA light source with 10W, 353 nm peak emission were illuminated to the specimens from 15cm above. The extracted 2 microliter of sample was plated on nutrient agar plate (BactoTM Brain Heart Infusion; BD, USA) with 10 minute intervals for 120 minute, respectively. It was incubated for 24 hours at 37 degree C and the colony forming units (CFUs) were then counted. Results. Compared the characteristics of LT photocatalyst with commercial P-25 photocatalyst, LT were shown higher activity than P-25. The LT coated experimental specimen surface had anatase crystal form, less than 20 nm of particle size and wide specific surface area. To evaluate the photocatalytic activity of specimens, methylene blue degradation reaction were used and about 5% of degradation rate were measured after 2 hours. The average contact angle was less than 20.indicating that the LT photocatalyst had hydrophilicity. In the antifungal activity test for Candida albicans, 0% survival rate were measured within 30 minute after irradiation of UVA light. Conclusion. From the results reported above, it is concluded that the UVA-LT photocatalytic reaction have an antifungal effect on the denture surface Candida albicans, and so that could be applicable to the clinical use as a cleaning method.