Factors influencing antioxidant phytochemical stability of teas

Tea is second only to water as the most consumed beverage in the world due to its health-promoting benefits and characteristic flavor. Even though many botanical teas such as yaupon holly (Ilex vomitoria) and mamaki (Pipturus albidus) are currently available in the tea market, only limited information is available on their polyphenolic contents containing diverse biological activities. Identification of phenolic compounds was performed using advanced analytical technique of mass spectrometry to provide polyphenolic profile of teas. To present fundamental information of phytochemical stability during tea storage, studies to determine the impacts of tea processing, different packaging materials, and various storage conditions on the phytochemical stability were conducted. Ascorbic acid addition and lowering pH successfully decreased the reduction of phenolic compounds by reducing the rate of oxidative degradation while tea pasteurization accelerated oxidative degradation. Glass bottles were most effective to retain higher concentration of polyphenolics. Tea polyphenolics at lower temperature (3 °C) without light exposure were higher retained in each tea. Tea cream, the complex formed by interaction between polyphenolics, caffeine, protein, and metal ions, is highly undesirable in tea industry since it causes haziness and cloudiness in tea infusion as well as deteriorates sensorial properties. Only limited information is available on tea creaming in non-fermented type teas such as green tea, yaupon holly, and mamaki even though many tea creaming compounds are present in these teas. Therefore, studies were conducted to determine the degree of contribution of the tea creaming compounds to tea creaming and to develop novel chemical methods to minimize tea creaming without detrimental effects. Methods applied in the present study defined that hydrophobic interaction was the driving force make tea cream insoluble in the solution. Results obtained by present studies provided fundamental and practical information to the tea industry in terms of phytochemical stability and suggested storage stability of phytochemicals should be considered during processing and storage, since it could be better retained or improved by applying appropriate methods

Epidemiological Characteristics of Nontuberculous Mycobacterial Pulmonary Disease in South Korea: A Meta-analysis of Individual Participant Data

Background Despite the global increase in nontuberculous mycobacterial pulmonary disease (NTM-PD), clinical characteristics show geographical variations. We investigated the clinical characteristics of patients with NTM-PD in South Korea. Methods We systematically reviewed articles concerning patients with NTM-PD in South Korea until February 2022. Individual participant data, regardless of treatment, were collected using a standard case report form. Results Data of 6,489 patients from 11 hospitals between 2002 and 2019 were analyzed. The mean age was 61.5±11.7 years, of whom 57.7% were women. Mycobacterium avium (41.4%) and Mycobacterium intracellulare (38.4%) comprised most of the causative species, followed by Mycobacterium abscessus subspecies abscessus (8.6%) and M. abscessus subspecies massiliense (7.8%). Bronchiectasis (59.4%) was the most common pulmonary comorbidity. Although reported cases of NTM-PD increased over the years, the proportions of causative species and radiologic forms remained similar. Distinct clinical characteristics were observed according to age and sex. Men were older at the time of diagnosis (median 63.8 years vs. 59.9 years, p<0.001), and had more cavitary lesions than women (38.8% vs. 21.0%, p<0.001). The older group (≥65 years) had higher proportions of patients with body mass index <18.5 kg/m2 (27.4% vs. 18.6%, p<0.001) and cavitary lesions (29.9% vs. 27.6%, p=0.009) than the younger group. Conclusion We conducted a meta-analysis of the clinical characteristics of patients with NTM-PD in South Korea, and found age- and sex-related differences in disease-specific severity. Further investigation would enhance our comprehension of the nature of the disease, and inherited and acquired host factors

Longitudinal association between adiposity changes and lung function deterioration

Background The longitudinal relationship between adiposity and lung function is controversial. We aimed to investigate the long-term association between adiposity changes and lung function in a middle-aged general Asian population. Methods In total, 5011 participants (average age, 54years; 45% men) were enrolled from a community-based prospective cohort. During the follow-up period (median 8years), both spirometry and bio-electrical impedance analysis were performed biannually. Individual slopes of the fat mass index (FMI; fat mass divided by the square of height in meters) and waist-to-hip ratio (WHR) were calculated using linear regression analysis. Multivariate linear mixed regression analysis was used to determine the long-term association between adiposity changes and lung function. Results The FMI was inversely associated with forced vital capacity (FVC) (estimated: − 31.8mL in men, − 27.8mL in women) and forced expiratory volume in 1s (FEV1) (estimated: − 38.2mL in men, − 17.8mL in women) after adjusting for baseline age, height, residential area, smoking exposure (pack-years, men only), initial adiposity indices, and baseline lung function. The WHR was also inversely associated with FVC (estimated = − 1242.2mL) and FEV1 (estimated = − 849.8mL) in men. The WHR-increased group showed a more rapid decline in lung function than the WHR-decreased group in both the fat-gain and fat-loss groups. Conclusion Adiposity was associated with the long-term impairment of lung function. Central obesity was the main driver of lung function impairment in the middle-aged general Asian population, regardless of fat mass changes

Relationship between vitamin D-binding protein polymorphisms and blood vitamin D level in Korean patients with COPD

BACKGROUND: In chronic obstructive pulmonary disease (COPD), the blood vitamin D3 level is generally low, and genetic polymorphisms of vitamin D-binding protein encoded by the GC gene are associated with COPD development. In this study, we examined the relationship between GC polymorphisms and plasma vitamin D3 level in Korean patients with COPD. METHODS: The study included 175 COPD patients from the Korean Obstructive Lung Disease Cohort. Multivariate analysis was conducted with adjustment for age, body mass index (BMI), lung function, smoking status, smoking amount, and seasonal variation in blood vitamin D level. Vitamin D deficiency was defined as a plasma 25-hydroxyvitamin D(3) level lower than 20 ng/mL. RESULTS: The mean plasma vitamin D3 level was 17.5 ng/mL. The GC1F variant (44.3%) and genotype 1F-2 (27.4%) were the most common. The plasma vitamin D3 level was lower in patients with the GC2 variant (estimated =−3.73 ng/mL) and higher in those with genotype 1F-1S (estimated =4.08 ng/mL). The GC2 variant was a significant risk factor for vitamin D deficiency (odds ratio =2.41). Among COPD clinical parameters, vitamin D deficiency was associated with a lower ratio of forced expiratory volume in 1 second to forced vital capacity (FEV(1)/FVC) regardless of GC polymorphisms. FEV(1)/FVC was higher in patients with genotype 1F-1F (estimated =3.61%) and lower in those with genotype 1F-2 (estimated =−3.31%). The 6-minute walking distance was shorter for patients with the GC1F variant (estimated =−38.91 m) and longer for those with the GC2 variant (estimated =26.98 m). The emphysema index was higher for patients with the GC1S variant (estimated =6.56%) and genotype 1F-1S (estimated =9.86%), regardless of the vitamin D level. CONCLUSION: The GC2 variant is a risk factor for vitamin D deficiency, and genotype 1F-1S is a protective factor against vitamin D deficiency. GC polymorphisms and vitamin D deficiency correlate with clinical outcomes for Korean patients with COPD

High-Dose Rifampicin for 3 Months after Culture Conversion for Drug-Susceptible Pulmonary Tuberculosis

Background This study aimed to determine whether a shorter high-dose rifampicin regimen is non-inferior to the standard 6-month tuberculosis regimen. Methods This multicenter, randomized, open-label, non-inferiority trial enrolled participants with respiratory specimen positivity by Xpert MTB/RIF assay or Mycobacterium tuberculosis culture without rifampicin-resistance. Participants were randomized at 1:1 to the investigational or control group. The investigational group received high-dose rifampicin (30 mg/kg/day), isoniazid, and pyrazinamide until culture conversion, followed by high-dose rifampicin and isoniazid for 12 weeks. The control group received the standard 6-month regimen. The primary outcome was the rate of unfavorable outcomes at 18 months post-randomization. The non-inferiority margin was set at <6% difference in unfavorable outcomes rates. The study is registered with ClinicalTrials.gov (NCT04485156) Results Between 4 November 2020 and 3 January 2022, 76 participants were enrolled. Of these, 58 were included in the modified intention-to-treat analysis. Unfavorable outcomes occurred in 10 (31.3%) of 32 in the control group and 10 (38.5%) of 26 in the investigational group. The difference was 7.2% (95% confidence interval, ∞ to 31.9%), failing to prove non-inferiority. Serious adverse events and grade 3 or higher adverse events did not differ between the groups. Conclusion The shorter high-dose rifampicin regimen failed to demonstrate non-inferiority but had an acceptable safety profile

Treatment shortening of drug-sensitive pulmonary tuberculosis using high-dose rifampicin for 3 months after culture conversion (Hi-DoRi-3): a study protocol for an open-label randomized clinical trial

Background : The standard treatment regimen for drug-sensitive tuberculosis (TB), comprising four companion drugs, requires a minimum duration of 6 months, and this lengthy treatment leads to poor adherence and increased toxicity. To improve rates of adherence, reduce adverse events, and lower costs, a simplified and shortened treatment regimen is warranted. Methods : This study is a multicenter, open-label randomized clinical trial of non-inferiority design that compares a new regimen with the conventional regimen for drug-sensitive pulmonary TB. The investigational group will use a regimen of high-dose rifampicin (30 mg/kg/day) with isoniazid and pyrazinamide, and the treatment will be maintained for 12 weeks after the achievement of negative conversion of sputum culture. The control group will be treated for 6 months with a World Health Organization-endorsed regimen consisting of isoniazid, rifampicin (10 mg/kg/day), ethambutol, and pyrazinamide. The primary endpoint is the proportion of unfavorable outcomes at 18 months after randomization. Secondary outcomes include time to unfavorable treatment outcome, time to culture conversion on liquid medium, treatment success rate at the end of treatment, proportion of recurrence at 18 months after randomization, time to recurrence after treatment completion, and adverse events of grade 3 or higher during the treatment. We predict a 10% unfavorable outcome for the control group, and 0% difference from the investigational group. Based on 80% verification power and a 2.5% one-sided significance level for a non-inferiority margin of 6%, 393 participants per group are required. Considering the 15% dropout rate, a total of 926 participants (463 in each group) will be recruited. Discussion : This study will inform on the feasibility of the treatment regimen using high-dose rifampicin with a shortened and individualized treatment duration for pulmonary TB. Trial registration : ClinicalTrials.gov NCT04485156.Registered on July 24, 2020.This work was supported by a grant from the Korea National Institute of Health (2020-ER5201-01), Republic of Korea. High-dose rifampicin tablets and capsules were donated from Yuhan (Seoul, Republic of Korea) for this study. The funder and donor had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript