The Positive Association between Melatonin-Containing Food Consumption and Older Adult Life Satisfaction, Psychoemotional State, and Cognitive Function.

The purpose of this study was to test the hypothesis that melatonin-containing food (FMT) consumption is associated with a better sleep schedule and cognitive and psychoemotional state in older adults. A cross-sectional study of 557 (79% females) older adults living in the community with a mean age of 68.9 ± 7.7, ranging from 50 to 90 years, was conducted. The study, conducted in May and September 2023 using a face-to-face interview, collected personal data and assessed FMT intake during the day (FMTday) and for dinner (FMTdinner), life satisfaction, positive and negative affect, depression severity, cognitive functions, and sleep characteristics. Multiple regression and logistic regression analysis, adjusted for co-factors, were used to assess the association between the studied indicators. Multiple regression analysis showed that older adults with higher FMT consumption are more satisfied with life (FMTdinner: ß = 0.107; ∆R2 = 0.011; p = 0.020), have a lower level of depression (FMTday: ß = -0.124; ∆R2 = 0.015; p = 0.003), and higher scores in positive affect (FMTday: ß = 0.169; ∆R2 = 0.016; p = 0.007; FMTdinner: ß = 0.136; ∆R2 = 0.019; p = 0.003). Logistic regression analysis showed that older adults with higher FMT consumption are less likely to have depression (FMTday: OR, 0.614; 95% CI, 0.436-0.864; p = 0.005; FMTdinner: OR, 0.671; 95% CI, 0.476-0.945; p = 0.023), and they perform better on logical thinking tests (FMTday: OR, 2.066; 95% CI, 1.131-2.204; p = 0.013; FMTdinner: OR, 1.887; 95% CI, 1.183-2.138; p = 0.033). A greater life satisfaction as well as a decrease in the cognitive impairment and psychoemotional state of older adults is associated with a higher consumption of melatonin-containing foods.

Association of Chrononutrition Indices with Anthropometric Parameters, Academic Performance, and Psychoemotional State of Adolescents: A Cross-Sectional Study.

Adolescents are an at-risk group for circadian misalignment. The contribution of sleep-wake rhythm instability to the psychoemotional, cognitive, and weight disorders of adolescents has been studied in sufficient detail. At the same time, there is insufficient information about the association between chrononutrition indices and the well-being of adolescents. The aim of this study is to investigate the relationship between chrononutrition indices and academic achievement, psychoemotional state, and anthropometric indicators in adolescents. The study involved 12,759 students in grades 6-11 of secondary schools, aged 14.2 ± 1.7 years old; 57.2% of whom were girls. Participants provided personal data, frequency and time of meals during the day and at night, on weekdays and weekends, and completed the Zung Self-Rating Depression Scale and the Yale Food Addiction Scale. There is a U-shaped association between eating mid-phase (EPFc), eating jetlag (EJL), and eating window (EW) with GPA, ZSDSI, and FA. At the same time, the frequency of night eating (NE) is linearly associated with the studied parameters. NE is the strongest predictor of ZSDSI (ß = 0.24), FA (ß = 0.04), and GPA (ß = -0.22). EPFc, EJL, and EW practically do not differ in the strength of their association with the studied indicators. ZSDSI is most closely associated with the chrononutrition indices. There is a weak negative association between BMI and EW (ß = -0.03) and NE (ß = -0.04). Thus, circadian eating disorders are more often observed in adolescents with poor academic performance, high levels of depression, and food addiction.

The Association between Melatonin-Containing Foods Consumption and Students' Sleep-Wake Rhythm, Psychoemotional, and Anthropometric Characteristics: A Semi-Quantitative Analysis and Hypothetical Application.

Food is an important source of melatonin (MT), which belongs to a group known as chronobiotics, a class of substances that affect the circadian system. Currently, no studies have been conducted on how the consumption of foods containing MT (FMT) is associated with indicators characterizing the human circadian system. In this study, we tested the hypothesis that FMT consumption is associated with chronotype and social jetlag. A total of 1277 schoolchildren and university students aged M (SD) 19.9 (4.1) years (range: 16-25 years; girls: 72.8%) participated in a cross-sectional study. Each participant completed an online questionnaire with their personal data (sex, age, height, weight, waist circumference, and academic performance) and a sequence of tests to assess their sleep-wake rhythm (the Munich Chronotype Questionnaire), sleep quality (the Pittsburgh Sleep Quality Index), and depression level (the Zung Self-Rating Depression Scale). Study participants also completed a modified food frequency questionnaire that only included foods containing MT (FMT). They were asked how many foods containing MT (FMT) they had eaten for dinner, constituting their daily serving, in the past month. The consumption of foods containing MT (FMT) during the day (FMTday) and at dinner (FMTdinner) was assessed using this test. Multiple regression analyses were performed to assess the association between the studied indicators. We found that higher FMTday values were associated with early chronotype (ß = -0.09) and less social jetlag (ß = -0.07), better sleep quality (ß = -0.06) and lower levels of depression (ß = -0.11), as well as central adiposity (ß = -0.08). Higher FMTdinner values were associated with a lower risk of central adiposity (ß = -0.08). In conclusion, the data obtained confirm the hypothesis that the consumption of foods containing MT (FMT) is associated with chronotype and social jetlag in adolescents and young adults.

Afternoon school shift is associated with increased risk of overweight/obesity in 11-14-year-old females with early and intermediate chronotype.

OBJECTIVE: The purpose of this study was to compare the anthropometric and sleep-wake rhythm characteristics of schoolchildren that attend school in morning and afternoon school shifts. METHODS: We recruited 18 481 individuals (females: 56.4%) aged 11 to 18 years old with an average age of 14.4 ± 1.7 years old. In total, 812 (4.2%) questionnaires were incomplete. The self-reported height and weight were used to assess the sex- and age-corrected body mass index of the participants. The Munich ChronoType Questionnaire was used to assess the chronotype, social jetlag, and sleep duration of the participants. RESULTS: In total, 12.6% of the participants were affected by overweight or obesity. The overweight and obesity incidence rate was higher among the students studying in the afternoon (odd ratio [95%CI]: 1.33 [1.16-1.52]). The afternoon school shift had a negative impact on the anthropometric indicators only in the 11-14-year-olds (1.29 [1.11-1.50]) and girls (1.26 [1.04-1.54]) with an early (1.27 [1.03-1.56]) and intermediate (1.30 [1.07-1.58]) chronotype. CONCLUSION: The data obtained indicated that the afternoon school shift is not ideal, especially for female children and adolescents under 15 years old with an early and intermediate chronotype.

Food addiction and emotional eating are associated with intradaily rest-activity rhythm variability.

PURPOSE: The aim of the present investigation was to study the associations among parameters characterizing eating behavior and actimetry-derived indices of circadian rhythm of motor activity. METHODS: The study involved 81 healthy participants (average age: 21.5 ± 9.6 y, women: 77.8%). Each study participant provided personal data, filled out the Yale Food Addiction Scale and the Dutch Eating Behavior Questionnaire, and wore a wrist actimeter for 7 consecutive days to record motor activity. Using time series treatments, we obtained: (a) three cosinor-derived parametric indices [Medline Estimating Statistics of Rhythm (MESOR), amplitude, and acrophase], and (b) four non-parametric indices [interdaily stability, intradaily variability (I.V.), most active 10-h period (M10), and least active 5-h period] characterizing the 24-h rhythm of motor activity. A multiple regression analysis adjusted for age, sex, and BMI was performed to assess the associations among the studied indicators. RESULTS: It was shown that I.V. is a predictor of symptoms of food addiction (ß = 0.242, P = 0.037) and emotional eating (ß = 0.390, P = 0.004), MESOR is a predictor of symptoms of food addiction (ß = 0.342, P = 0.003), and M10 predicts restraint (ß = 0.257, P = 0.015) and emotional eating (ß = 0.464, P = 0.001). CONCLUSION: It was shown for the first time that an increase in symptom counts of food addiction is associated with an increase in the average level and fragmentation of 24-h rhythm of motor activity. LEVEL OF EVIDENCE: Level V, cross-sectional descriptive study.

Later school start time is associated with better academic performance, sleep-wake rhythm characteristics, and eating behavior.

There are numerous studies which show that an early school start time has a negative impact on the sleep, well-being, and academic performance of students. There is not enough information on the association between school start time and eating disorders, however: the disruption of the circadian rhythm is known to be a risk factor for eating disorders. The aim of this study is to analyze the relationship between school start time (SST) and the sleep, well-being, academic performance, and eating behavior of children and adolescents. The study was conducted in April and May 2021 in two regions of Russia: the Komi Republic and Yekaterinburg. The online study involved the anonymous and voluntary participation of 6571 students in grades 6-11 (mean age: 14.5 ± 1.6 years, 60.1% female), who have morning classes. All participants were divided into three groups according to SST: 08:00 (n = 3661), 08:30 (n = 2020), and 09:00 (n = 890). Each participant of the study indicated their place of residence, SST, age, sex, height, weight, academic performance, and filled out the Munich Chronotype Questionnaire, the Zung Self-Rating Depression Scale, and the Yale Food Addiction Scale for Children. As a result of multiple regression analysis, it was shown that schoolchildren with SST of 09:00 wake up at a later time on school days (B = 0.432; ΔR2 = 0.039), sleep more (B = 0.293; ΔR2 = 0.004), have less pronounced social jetlag (B = -0.223; ΔR2 = 0.005) and sleep loss (B = -0.292; ΔR2 = 0.005), and higher academic performance (B = 0.113; ΔR2 = 0.003) than schoolchildren with SST of 08:00. As a result of logistic regression analysis, it was found that the frequency of the detection of food addiction is ~30% lower in schoolchildren with SST of 09:00 (OR = 0.690; 95% CI = 0.485-0.981) than in their peers with SST of 08:00. Thus, an overly early SST in Russia has a negative impact on the sleep function, academic performance, and eating behavior of children and adolescents.

Association between food addiction and time perspective during COVID-19 isolation.

PURPOSE: The concept of time perspective (TP) implies that a mental focus on past, present, or future affect a person makes decisions and take action. Inability to plan their life for a sufficiently long time perspective due to the COVID-19 pandemic appeared to have a pronounced impact on a human's lifestyle influencing their thoughts, feelings, and behaviors, including eating behavior. This study tested two hypotheses: (a) that during COVID-19 isolation, the incidence rate of food addiction is increased, and (b) people with present TP are more likely exhibited signs of food addiction (FA). METHODS: The final study sample included 949 people, mean age 21.8 ± 7.8 years (range: 17-71 years, women: 78.3%). Each participant indicated their personal data and completed Yale Food Addiction Scale and the Zimbardo Time Perspective Inventory. RESULTS: There was an increased incidence rate of FA (OR = 1.678, 95% CI = 1.324, 2.148, p = 0.000) during COVID-19 isolation. Individuals with balanced, future, and past positive TP were less likely to exhibit symptoms of FA. Persons with past negative, and present hedonistic TP were more likely to exhibit signs of FA. CONCLUSION: There was an increased incidence rate of FA during COVID-19 isolation. Persons with shortened time horizon are more likely to exhibit symptoms of FA. LEVEL OF EVIDENCE: Level V, cross-sectional descriptive study.

Food addiction and weight in students with high academic performance.

OBJECTIVE: The purpose of this study was to analyse the relationships between food addiction (FA), anthropometric characteristics and academic performance. DESIGN: The average age (sd) of the participants was 17·5 (sd 2·7) years (64·1 % female). Each study participant indicated their sex, height, weight and academic performance and completed the Yale Food Addiction Scale. SETTING: Syktyvkar, Kirov, Tyumen, Yekaterinburg, Russia; Aizawl, India. PARTICIPANTS: The study involved 3426 people. RESULTS: FA was found in 8·7 % of participants from Russia and 14·6 % from India. In schoolchildren but not in university students, high academic performance was associated with a higher incidence rate of FA detection (OR = 1·16, 95 % CI 1·07, 1·26) and a lower BMI (OR = 0·72, 95 % CI 0·56, 0·94). CONCLUSIONS: These data showed an increased incidence rate of FA detection in adolescents with high academic performance.

Food preferences and YFAS/YFAS-C scores in schoolchildren and university students.

PURPOSE: Food addiction (FA) is one of the causes of widespread obesity in modern society. It was shown that there is an age-associated increase in incidence rate of FA in adolescents/young adults. The purpose of this study was to analyze food preferences in schoolchildren and university students with FA. METHODS: High school and university students (N = 1607; age: 17.8 ± 2.7 years; girls: 77.0%) located in four settlements of Russia anonymously took part in the study. Study participants provided personal data (age, sex, height, and weight) and completed the Yale Food Addiction Scale, the Zung Self-Rating Depression Scale and the Munich ChronoType Questionnaire. In addition, they indicated food products with which they had problems. RESULTS: The frequency of detection of FA among university students was twice as high as among schoolchildren. University students with FA were 20.2% more likely than schoolchildren to report the symptom 'use continues despite knowledge of adverse consequences,' and 13.7% more likely to report the symptom 'tolerance.' Schoolchildren and university students with FA most often noted that foods high in sugar and fat were problematic. University students with FA also reported that foods with a high carbohydrate content were problematic. CONCLUSION: In university students with FA, in comparison with schoolchildren with FA, there is an increase in list of problematic food products, mainly due to products with a high carbohydrate content. LEVEL OF EVIDENCE: Level V, cross-sectional descriptive study.

Impact of COVID-19 Lockdown in Eating Disorders: A Multicentre Collaborative International Study.

BACKGROUND: The COVID-19 lockdown has had a significant impact on mental health. Patients with eating disorders (ED) have been particularly vulnerable. AIMS: (1) To explore changes in eating-related symptoms and general psychopathology during lockdown in patients with an ED from various European and Asian countries; and (2) to assess differences related to diagnostic ED subtypes, age, and geography. METHODS: The sample comprised 829 participants, diagnosed with an ED according to DSM-5 criteria from specialized ED units in Europe and Asia. Participants were assessed using the COVID-19 Isolation Scale (CIES). RESULTS: Patients with binge eating disorder (BED) experienced the highest impact on weight and ED symptoms in comparison with other ED subtypes during lockdown, whereas individuals with other specified feeding and eating disorders (OFSED) had greater deterioration in general psychological functioning than subjects with other ED subtypes. Finally, Asian and younger individuals appeared to be more resilient. CONCLUSIONS: The psychopathological changes in ED patients during the COVID-19 lockdown varied by cultural context and individual variation in age and ED diagnosis. Clinical services may need to target preventive measures and adapt therapeutic approaches for the most vulnerable patients.

COVID Isolation Eating Scale (CIES): Analysis of the impact of confinement in eating disorders and obesity-A collaborative international study.

Confinement during the COVID-19 pandemic is expected to have a serious and complex impact on the mental health of patients with an eating disorder (ED) and of patients with obesity. The present manuscript has the following aims: (1) to analyse the psychometric properties of the COVID Isolation Eating Scale (CIES), (2) to explore changes that occurred due to confinement in eating symptomatology; and (3) to explore the general acceptation of the use of telemedicine during confinement. The sample comprised 121 participants (87 ED patients and 34 patients with obesity) recruited from six different centres. Confirmatory Factor Analyses (CFA) tested the rational-theoretical structure of the CIES. Adequate goodness-of-fit was obtained for the confirmatory factor analysis, and Cronbach alpha values ranged from good to excellent. Regarding the effects of confinement, positive and negative impacts of the confinement depends of the eating disorder subtype. Patients with anorexia nervosa (AN) and with obesity endorsed a positive response to treatment during confinement, no significant changes were found in bulimia nervosa (BN) patients, whereas Other Specified Feeding or Eating Disorder (OSFED) patients endorsed an increase in eating symptomatology and in psychopathology. Furthermore, AN patients expressed the greatest dissatisfaction and accommodation difficulty with remote therapy when compared with the previously provided face-to-face therapy. The present study provides empirical evidence on the psychometric robustness of the CIES tool and shows that a negative confinement impact was associated with ED subtype, whereas OSFED patients showed the highest impairment in eating symptomatology and in psychopathology.

Food addiction in young adult residents of Russia: Associations with emotional and anthropometric characteristics.

The incidence of food addiction (FA) and associations between FA and anthropometric and psycho-emotional characteristics of young Russian adults were studied. In this study, 1,237 students (age, M = 20.6, SD = 4.6 years; 79% females) of universities located in four cities of Russia were attended. They provided demographics and filled in the Yale Food Addiction Scale (YFAS), the Dutch Eating Behavior Questionnaire, and the Zung Self-Rating Depression Scale. Data were analysed via Chi-squared tests, logistic regression analysis, and an analysis of covariance. 13.2% of participants met diagnostic criteria for FA based on the YFAS. On average, the participants reported 2.6 FA symptoms (SD = 1.5). FA was more commonly detected in females (OR = 1.86, 95% CI = 1.10, 3.15, p = .021). No relationship was found between age and the incidence of FA. Significant positive associations between FA, the severity of depression (OR = 2.31, 95% CI = 1.91, 2.80, p = .000), and an emotional eating behaviour (OR = 1.45, 95% CI = 1.20, 1.76, p = .000) were found. The waist-to-height ratio was found to be the anthropometric indicator most closely associated with FA (OR = 1.49, 95% CI = 1.27, 1.76, p = .000). HIGHLIGHTS: The prevalence of food addiction in the current sample was 13.2%. In young Russian adults, emotional eating behaviour and depression are associated with food addiction. In young Russian adults, the waist-to-height ratio is the anthropometric indicator most closely associated with food addiction.

Food addiction and symptoms of depression among inhabitants of the European North of Russia: Associations with sleep characteristics and photoperiod.

The purpose of this investigation was to study the sleep-wake rhythm characteristics of young persons with food addiction (FA) and symptoms of depression. A total of 2,360 young persons living in northern European Russia were included in the study. The average age of the respondents (± standard deviation [SD]) was 17.9 [4.6] years (66.6% female). Each participant provided personal data and filled in three questionnaires: the Munich Chronotype Questionnaire, the Zung Self-Rating Depression Scale, and the Yale Food Addiction Scale. FA was detected in 8.9% of respondents, and moderate-to-severe symptoms of depression were detected in 16.7% of respondents. FA and depressive symptoms were more often detected in females. Age and body mass index were shown to be significantly associated with FA. There were positive associations between the time of sunrise and FA and depressive symptoms. Persons who had symptoms of depression also tended to have a later chronotype, lower sleep efficiency, later sleep onset, higher sleep inertia, and greater sleep latency on school days. A positive relationship between FA and the time of sleep onset on school days was also revealed. Thus, the results indicate that prolonged wakefulness in the evening after sunset was associated with FA.

Chronotype, social jetlag, and time perspective.

The phase of entrainment (chronotype) is known to be associated with time perspective (TP), suggesting that the state of circadian system is involved in the long-term planning of human life. However, little is known regarding the influence of circadian misalignment on long-term planning ability. The aim of this study was to investigate the association between social jetlag (SJL) and TP. A total of 1064 schoolchildren and university students (mean age ± standard deviation, 19.2 ± 2.9 years; range, 15-25 years; females, 71.7%) from four cities in the Russian Federation located between 56.9 and 61.7 degrees North completed the Munich ChronoType Questionnaire, the Pittsburgh Sleep Quality Index, the Seasonal Pattern Assessment Questionnaire, and Zimbardo Time Perspective Inventory. Study participants also indicated personal data (age, sex, height weight, place of residence, and achievements). A multiple regression analysis with stepwise inclusion of predictors in the model was performed to evaluate associations between time perspective characteristics (dependent variables) and predictor variables. The change in R2 was used as the measure of effect size. Chronotype was found to be a moderate predictor of future TP (B = 0.034; ΔR2 = 0.037). In addition, sleep quality was found to be a moderate predictor of past negative (B = 0.043; ΔR2 = 0.074), present fatalistic (B = 0.021; ΔR2 = 0.035), and deviation from balanced TP (B = 0.034; ΔR2 = 0.066). Mood seasonality was a moderate predictor of present hedonistic TP (B = 0.016; ΔR2 = 0.038), and social jetlag was a weak predictor of present fatalistic (B = 0.052; ΔR2 = 0.019), future (B = -0.033; ΔR2 = 0.004), and deviation from balanced TP (B = 0.047; ΔR2 = 0.012). In conclusion, this study found a weak but significant association between social jetlag and TP in adolescents and young adults.

Food addiction in Russian adolescents: Associations with age, sex, weight, and depression.

OBJECTIVE: Eating disorders are a cause of the recent obesity epidemic. Food addiction (FA) and factors associated with eating disorders have not been adequately studied in adolescents. METHOD: The final study sample included 1,144 students. Study participants were asked to indicate their age, sex, and month of birth and fill out the Yale Food Addiction Scale for Children and Zung Self-Rating Depression Scale. RESULTS: Of the total number of adolescents studied, 4.5% had FA. It was found that an increased rate of FA diagnosis existed in adolescents with moderate-to-severe depression (P < 0.000), overweight and obese individuals (P < 0.002), girls (P < 0.038), and the 17- to 18-year-old age group (P < 0.007). CONCLUSION: The data indicate that FA is positively associated with depression, obesity, age, and sex.

In vitro gastrointestinal-resistant pectin hydrogel particles for ß-glucuronidase adsorption.

Pectin hydrogel particles (PHPs) were prepared by ionotropic gelation of low methylesterified pectin of Tanacetum vulgare L. with calcium ions. Wet PHPs prepared from TVF exhibited a smaller diameter and the lower weight as well as exhibited the best textural properties in terms of hardness and elasticity compared to the PHPs prepared from commercial low methylesterified pectin (CU701) used for comparison. Upon air drying, PHPs prepared from CU701 became small and dense microspheres whereas the dry PHPs prepared from TVF exhibited a drop-like shape. The morphology of dry PHPs determined by scanning electron microscopy revealed that the surface of the TVF beads exhibited fibred structures, whereas the PHPs prepared from CU701 exhibited a smooth surface. The characterization of surface roughness using atomic force microscopy indicated less roughness profile of the PHPs prepared from TVF than CU701. PHPs prepared from TVF were found to possess in vitro resistance to successive incubations in simulated gastric (SGF), intestinal (SIF), and colonic fluid (SCF) at 37 °C for 2, 4 and 18 h, respectively. The PHPs prepared from CU701 swelled in SGF and then lost their spherical shape and were fully disintegrated after 4 h of incubation in SIF. The PHPs from TVF, which were subjected to treatment with SGF, SIF and SCF, were found to adsorb microbial ß-glucuronidase (ßG) in vitro. The data obtained offered the prospect for the development of the PHPs from TVF as sorbents of colonic ßG for the inhibition of re-absorption of estrogens.

Wrist temperature and cortisol awakening response in humans with social jetlag in the North.

The discrepancy between biological and social rhythms known as social jetlag (SJL) is common in modern society and has a range of negative consequences for cognitive functioning, well-being and health. Social jetlag is typical for people with late chronotypes. As shown earlier, the prevalence of individuals with a late chronotype is higher among the residents of high latitudes. Therefore, a higher rate of detection of people with SJL should be expected in the North. In this study we assessed the detection rate of SJL among 62 young inhabitants of the European North of Russia (the Komi Republic), and the relationship between SJL, the circadian rhythm of the wrist temperature, and the cortisol awakening response (CAR). The detection rate of SJL was 65% among the people examined. A significant decrease in the amplitude (A) of circadian rhythm of wrist temperature: (ß = -0.34 (CI 95%: -0.66 to -0.33); F1,60 = 10.4; p < 0.0001; η(2) = 0.31), an increased incidence of depression: No-SJL = 4.5%; SJL = 17.5% (H = 4.84; p < 0.05), and a tendency for an increase in CAR was also observed in the SJL group. There were sex differences in sensitivity to SJL. Females with SJL but not males had higher global seasonality scores (ß = 0.51 (CI 95%: 0.21 to 0.81); F1,33 = 10.9; p < 0.002; η(2) =0.24), shorter sleep duration (ß = -0.52 (CI 95%: -0.82 to -0.22); F1,33 = 12.9; p < 0.001; η(2) = 0.28), worse sleep quality (ß = 0.39 (CI 95%: 0.07 to 0.72); F1,33 = 6.31; p < 0.017; η(2) = 0.16) and lower A of circadian rhythm of wrist temperature (ß = -0.18 (CI 95%: -0.55 to 0.18); F1,33 = 4.48; p < 0.043; η(2) = 0.13) compared with females without SJL. Thus, our data indicate that 40 of 62 participants of investigation had social jetlag. A decrease of the amplitude of the circadian rhythm of the wrist temperature appears to be an objective marker of SJL. Social jetlag had a strong negative impact on females but not on males.

Sleep characteristics, chronotype and winter depression in 10-20-year-olds in northern European Russia.

The purpose of this work was to examine the relationships between geographical coordinates and the prevalence of winter depression (SADW ), and to compare the sleep characteristics and chronotype of youths with and without SADW . We conducted a cross-sectional study of self-reported sleep characteristics, chronotype and winter depression in northern European Russia. Two questionnaires, the Munich Chronotype Questionnaire (MCTQ) and the Seasonal Pattern Assessment Questionnaire (SPAQ), were administered to a total of 3435 adolescents aged 10-20 years (1517 males and 1918 females). The prevalence of SADW in the study population was 8.4% and sub-SADW 11.8%. Four variables predicted the likelihood of SADW in youths: sex [higher in females: odds ratio (OR): 1.87, P < 0.0001], age (increases with age: OR: 1.09, P < 0.001), latitude (higher in the North: OR: 1.49, P < 0.029) and position in the time zone (higher in the West: OR: 1.61, P < 0.001). Later sleeping and waking, longer sleep latencies, more severe sleep inertia, shorter total sleep times and lower sleep efficiencies were observed in both males and females with SADW . The influence of SADW on sleep characteristics was more pronounced on school days. Significant phase delays of the sleep-wake rhythm and severe social jetlag (the difference between the mid-point of sleep phase at weekends and on workdays) were observed in females with SADW , but not in males. There are significant differences in sleep characteristics and chronotype between people with SADW and no-SAD. We demonstrate that both latitude of residence and location within the time zone are significant predictors of SADW in young inhabitants of the North.

Impact of cabbage pectin-protein complex on microbial ß-glucuronidase activity.

We previously demonstrated that pectin-protein complex (PPC) isolated from white cabbage adsorbs the ß-glucuronidase (ßG) enzyme of E. coli. Concurrently, we discovered a significant increase in ßG activity in the presence of PPC. The aim of this study is to identify the structural components of PPC that are responsible for ßG adsorption and activation. PPC was isolated from white cabbage using a saline solution containing hydrochloric acid (pH 1.5) at 37 °C for 4 h. PPC proteins were precipitated by aqueous 10% (m/v) trichloroacetic acid to yield the pectin-protein fractions PPC1 and PPC2. PPC was digested using 1,4-α-d-galacturonase, yielding the PPC6 fraction. Partial acid hydrolysis of PPC revealed the galacturonan fraction, PPC3, to be the core of the macromolecule. The purified PPC4 and PPC5 fractions were isolated from PPC by ion-exchange chromatography on DEAE-cellulose. ßG activity and its adsorption in the PPC fractions were studied in vitro. Crystalline cellulose was used as a control. This study found that the PPC3 fraction (the galacturonan core) does not adsorb ßG and does not affect its activity. The adsorption of ßG in the PPC samples is inversely proportional to the degree of methyl esterification of its carbohydrate component. The PPC4 and PPC5 fractions adsorb the highest proportion of ßG (51.2% and 54%, respectively). The stimulation of ßG enzyme activity is directly proportional to the protein content of the PPC sample. The PPC and PPC1 samples have the greatest ability to increase ßG activity (57.6% and 52.1%, respectively).