A systematic literature review of observational studies of the bidirectional association between metabolic syndrome and migraine.

AIMS: To evaluate all epidemiological evidence in the literature linking the metabolic syndrome (MetS) and migraine in adults. METHODS: Database (Medline, Embase; published reports up to November 2017) and manual searches were performed. Information on data collection, sample characteristics, study design, MetS and migraine assessment, and results was extracted from each relevant publication. The methodological quality of each study was also assessed. RESULTS: A total of 15 observational epidemiological studies in adults, published between 2009 and 2017, were retrieved. Of these, one employed a prospective design, while the rest had a cross-sectional (13 studies) or case-control (one study) design. Five studies assessed the presence of migraine in individuals with MetS, whereas 10 studies assessed the presence or risk of MetS in migraineurs. Most participants were female hospital outpatients. The sole prospective cohort study reported 11-year MetS incidence of 21.8% in migraineurs with aura, 16.8% in migraineurs without aura and 14.5% in subjects without headaches. Most studies (60%) provided no statistical estimates of association. Methodological flaws included selection biases, lack of power analysis, unsuitable research plans and no multivariable analyses. Meta-analysis was not feasible with the available data. CONCLUSION: Our systematic review has identified major gaps in knowledge and weaknesses in research that should provide an impetus for future epidemiological investigations using more rigorous methodology, large general-population prospective cohorts, and substantial data on dietary behaviours and lifestyle.

[Experimental verification of thulium lithotripsy].

AIM: Experimental evaluation of the efficacy and safety of lithotripsy using a new pulsed thulium fiber laser operating at a wavelength of 1.94 microns, peak power of 500 watts (maximum average power of 50 watts) by comparing it with a holmium laser operating at a wavelength of 2.1 microns (average maximum power 100 W and 120 W). RELEVANCE: The proportion of minimally invasive surgery in the management of urolithiasis, including retrograde intrarenal surgery, is steadily growing. The most appropriate tool for stone destruction is a laser. To date, the gold standard of minimally invasive surgical treatment of nephrolithiasis is holmium laser lithotripsy, which uses a laser on yttrium-aluminum-garnet activated by holmium ions (Ho: YAG) operating at a wavelength of 2.1 m. However, in recent years, lasers on a Tm-activated fiber with a wavelength of 1.94 m have become increasingly popular since the water absorption coefficient for the Tm radiation of a fiber laser is 5.5 times higher than for a Ho: YAG laser and in 2.2 times higher than for the Tm: YAG laser. This difference may translate into greater effectiveness and speed of stone crushing, which in turn leads to shorter operating time. MATERIALS AND METHODS: This article describes physical foundations of holmium and thulium laser radiation, the mechanisms of stone fragmentation, data from a series of experiments comparing the efficiency and safety of ex-vivo lithotripsy using a holmium solid-state laser with a wavelength of 2.1 m and a thulium fiber laser with a wavelength of 1.94 m. RESULTS: The study findings suggest that the STA IRE-Polyus thulium fiber laser operating at a wavelength of 1.94 microns and a maximum power of 500 watts has several advantages over the holmium laser in the stone fragmentation in urological practice. CONCLUSION: The results of the experimental work allow us to conclude that the use of a thulium fiber laser operating at a wavelength of 1.94 m and a maximum peak power of 500 W enables highly effective and safe lithotripsy.

Ring and unimodal angular-frequency distribution of THz emission from two-color femtosecond plasma spark.

We study angular and frequency-angular distributions of the terahertz (THz) emission of the low-frequency region (0.3-3 THz) from a two-color femtosecond plasma spark experimentally and in three-dimensional numerical simulations. We investigate the dependence of the angular shapes of the THz radiation on focusing conditions and pulse durations by using two laser facilities (pulse durations 35 and 150 fs) for different focusing geometries. Our experiments and simulations show that decrease in the numerical aperture from NA ≈0.2 to NA ≈0.02 results simultaneously in (I) squeezing of the THz angular distribution and (II) formation of the bright conical emission in the THz range. The moderate focusing NA ≈0.05, which forms the relatively narrow unimodal THz angular distribution, is identified as optimal in terms of angular divergence. Numerical simulations with carrier wave resolved show that bright THz ring structures appear at the frequencies ≥2 THz for longer focuses (NA ≈0.02), while for optimal focusing conditions NA ≈0.05 the conical emission develops at THz frequencies higher than 10 THz.

Dyslipidemia as a Potential Moderator of the Association between Hearing Loss and Depressive Symptoms.

OBJECTIVES: Knowledge about moderation of the association between hearing loss and depression is scant. We investigated dyslipidemia as a potential moderator of the association between hearing/hearing loss and depressive symptoms. DESIGN: Cross-sectional study. SETTING: General population-based cohort in France (SU.VI.MAX 2; 2007-2009). PARTICIPANTS: N= 4,307 adults (mean age = 61.5 ± 6.1 y; 59.6% women). MEASUREMENTS: A score ≥ 16 on the Center for Epidemiologic Studies Depression Scale defined presence of depressive symptoms. Mean hearing level for each ear was defined as the pure-tone average of the following thresholds: 0.5, 1.0, 2.0 and 4.0 kHz; the value for the better hearing ear was retained for analysis. Hearing loss was defined as inability to hear at thresholds ≥ 25 dB in both ears. A subjective measure of perceived hearing loss was also used. Serum triglyceride, total-, LDL- and HDL-cholesterol concentrations were assessed in fasting blood samples and established cutoffs were used in multivariable logistic regression models. The interaction between hearing/hearing loss (independent variables) and each of the four lipid parameters was tested. RESULTS: Even though the interaction tests regarding LDL-, HDL- cholesterol, and triglyceride status were statistically significant, the subgroup analyses revealed few significant and somewhat unexpected findings. In fact, among individuals with low LDL-cholesterol, unlike their counterparts with high LDL-cholesterol, there was an inverse association between hearing level in the better hearing ear and depressive symptoms (OR= 0.94; 95% CI: 0.89-0.99). Regarding the subjective measure of hearing, a few of the dyslipidemia-moderated associations were statistically significant, albeit not all in the predicted direction. CONCLUSIONS: The findings provide some support for moderation of the association between hearing/hearing loss and depressive symptoms by dyslipidemia, with important lipid-specific and hearing measure-specific differences. The results could serve as impetus for future investigations in order to identify and target population subgroups with increased vulnerability to depression in the context of both sensory disability and aging.

Ultrabroad Terahertz Spectrum Generation from an Air-Based Filament Plasma.

We have solved the long-standing problem of the mechanism of terahertz (THz) generation by a two-color filament in air and found that both neutrals and plasma contribute to the radiation. We reveal that the contribution from neutrals by four-wave mixing is much weaker and higher in frequency than the distinctive plasma lower-frequency contribution. The former is in the forward direction while the latter is in a cone and reveals an abrupt down-shift to the plasma frequency. Ring-shaped spatial distributions of the THz radiation are shown to be of universal nature and they occur in both collimated and focusing propagation geometries. Experimental measurements of the frequency-angular spectrum generated by 130-fs laser pulses agree with numerical simulations based on a unidirectional pulse propagation model.

Consumption of Dairy Products and Cognitive Functioning: Findings from the SU.VI.MAX 2 Study.

OBJECTIVES: Research concerning the link between dairy product intake and cognition is scant while experimental studies suggest links through various biological mechanisms. This study's objective was to examine the cross-time associations of total and specific dairy product consumption with cognitive performance in aging adults. We also explored compliance with dairy intake recommendations in France. DESIGN: The study was based on the «Supplémentation en Vitamines et Minéraux Antioxydants¼ randomized trial (SU.VI.MAX, 1994-2002) and the SU.VI.MAX 2 observational follow-up study (2007-2009). SETTING: A general-population cohort in France. PARTICIPANTS: N=3,076 participants included in both the SU.VI.MAX and SU.VI.MAX 2 studies. MEASUREMENTS: Dairy product consumption was estimated using repeated 24h records (1994-1996; mean=10 records, SD=3). Cognitive performance was assessed by neuropsychologists after an average of 13 years post-baseline via a battery of six validated tests. Mean age at the time of the cognitive function evaluation was 65.5 (SD=4.6) years. Principal component analysis revealed factors for verbal memory and working memory. Associations of energy-adjusted dairy product consumption and compliance with the respective dietary guidelines with subsequent cognitive impairment were examined using ANCOVA, providing mean differences (95% confidence intervals, CI) according to tertiles (T), adjusted for confounders including overall dietary patterns. RESULTS: Total dairy product consumption was not associated with cognitive function. However, milk intake was negatively associated with verbal memory performance: mean difference T3 versus T1= -0.99 (-1.83, -0.15). Among women, consuming more than the recommended amount of dairy was negatively associated with working memory performance: excess versus adequate = -1.52 (-2.93, -0.11). CONCLUSION: Our results indicate that dairy products consumption and especially compliance with dietary guidelines regarding dairy product intake are differentially associated with performance in specific cognitive domains after a comprehensive adjustment for lifestyle factors, health status markers and dietary patterns. Further longitudinal research is needed given the limited data available.

Determining the association between types of sedentary behaviours and cardiometabolic risk factors: A 6-year longitudinal study of French adults.

AIM: This study identified the longitudinal associations between leisure-time sedentary behaviours [television (TV) viewing, computer use and reading (h/week)] and cardiometabolic risk factors, including the metabolic syndrome. METHODS: A total of 2517 participants (mean±SD age: 55.5±4.9 years) were assessed in 2001 and in 2007 for physical activity and leisure-time sedentary behaviours, anthropometry, body composition, blood pressure, fasting blood glucose and lipids, using standardized methods. Multivariate generalized linear (beta, 95% CI and P values) and logistic (OR and 95% CI) regression models were used to assess cross-sectional associations between sedentary behaviours and cardiometabolic risk factors, while a 6-year longitudinal study explored these associations as well as the odds of developing the metabolic syndrome, as defined by the NCEP ATPIII. RESULTS: Increased TV viewing time over the follow-up period was positively associated with increases in body mass index (BMI; P<0.01) and percent body fat (P<0.001), and marginally with waist circumference (P=0.06). Reverse associations were also found, with changes in BMI, percent fat mass and waist circumference positively associated with TV viewing and computer use. Associations between reading and cardiometabolic risk factors were less consistent. Each 1-h/week increase in baseline TV viewing and in reading was associated with an increase in the chances of developing the metabolic syndrome (OR=1.031, 95% CI: 0.998-1.060, P=0.07; and OR=1.032, 95% CI: 1.002-1.065, P=0.02; respectively). CONCLUSION: The present study data emphasizes the notion of differential associations of specific sedentary behaviours with cardiometabolic risk factors. They are also evidence that different longitudinal associations should be taken into account when designing public health objectives of interventions aimed at improving cardiometabolic health.

Propagation equation for tight-focusing by a parabolic mirror.

Part of the chain in petawatt laser systems may involve extreme focusing conditions for which nonparaxial and vectorial effects have high impact on the propagation of radiation. We investigate the possibility of using propagation equations to simulate numerically the focal spot under these conditions. We derive a unidirectional propagation equation for the Hertz vector, describing linear and nonlinear propagation under situations where nonparaxial diffraction and vectorial effects become significant. By comparing our simulations to the results of vector diffraction integrals in the case of linear tight-focusing by a parabolic mirror, we establish a practical criterion for the critical f -number below which initializing a propagation equation with a parabolic input phase becomes inaccurate. We propose a method to find suitable input conditions for propagation equations beyond this limit. Extreme focusing conditions are shown to be modeled accurately by means of numerical simulations of the unidirectional Hertz-vector propagation equation initialized with suitable input conditions.

Overall and abdominal adiposity in midlife and subsequent cognitive function.

OBJECTIVES: The scientific literature supports a link between midlife adiposity and cognitive function or decline but most studies to-date have investigated only overall adiposity, often omitting important confounders from the analyses. We investigated in a cross-time design the relationships between two different midlife adiposity markers and subsequent cognitive function, testing midlife dietary patterns as a potential confounder of the associations. DESIGN: The study was based on the «Supplémentation en Vitamines et Minéraux Antioxydants¼ randomized trial (SU.VI.MAX, 1994-2002) and the SU.VI.MAX 2 observational follow-up study (2007-2009). SETTING: A general-population cohort in France. PARTICIPANTS: N=2,817 individuals (1,493 men and 1,324 women) included in both the SU.VI.MAX and SU.VI.MAX 2 studies. MEASUREMENTS: The cognitive performance of 2,817 middle-aged adults participating in the SU.VI.MAX (Supplémentation en Vitamines et Minéraux Antioxydant) study was assessed in 2007-2009 using 6 neuropsychological tests. Principal component analysis was used to derive specific cognitive scores. A composite cognitive score was also computed. Body mass index (BMI) and waist circumference (WC) were measured 13 years earlier (1994). Associations between midlife adiposity and cognitive functioning were estimated through covariance analyses. RESULTS: After adjustment for obesity-related cardio-metabolic parameters, higher BMI and larger WC at midlife predicted lower executive function. For example, the adjusted mean difference (95% confidence interval) for 1 SD increase in WC was -0.48 (-0.97, 0.00). Obese participants in midlife showed an adjusted mean difference (95% confidence interval) of -1.68 (-3.15, -0.22) compared with non-obese. Further adjustment for midlife dietary patterns slightly attenuated these associations. No relationships were observed with verbal memory or global cognitive function. CONCLUSION: Midlife overall and abdominal adiposity were similarly associated with lower executive functioning scores. Dietary patterns may partly explain such a relationship, arguing for the importance of controlling for lifestyle confounders in future studies.

Transformation of terahertz spectra emitted from dual-frequency femtosecond pulse interaction in gases.

We demonstrate that the two basic physical mechanisms of terahertz (THz) generation in a femtosecond filament, namely, the free electron photocurrent and the nonlinear polarization of neutrals, can be identified through the spectral analysis of THz radiation. The contribution from the photocurrent peaks at the units of THz, while the neutrals yield the peak at the tens of THz. We suggest the practical implementation of such spectral analysis by varying the initial transform-limited laser pulse duration.

Dietary patterns, inflammation and the metabolic syndrome.

AIM: The study of dietary patterns offers a comprehensive, real-life approach towards examining the complex diet and disease relationship. The simultaneous association of dietary patterns with inflammation and the metabolic syndrome (MetS) has not been extensively reviewed. This report reviews the association of dietary patterns with inflammation in the context of the MetS. METHODS: Original English-language research studies with humans were identified via MEDLINE, using inflammation, MetS, whole diets and dietary patterns as keywords. The findings were carefully examined and synthesized along consistent axes. RESULTS: Many observational and a few prospective studies, as well as some randomized controlled trials (RCTs), support an inverse association between a Mediterranean dietary pattern and markers of inflammation. The link is generally independent of traditional cardiovascular disease (CVD) risk factors and weight loss. The few studies that have examined the association between following a healthy dietary pattern, evaluated using various diet quality scores, and inflammation report an inverse association; however, this association was attenuated upon adjusting for CVD risk factors. A Mediterranean dietary pattern has also been associated with a reduced risk of the MetS in several cross-sectional studies and a few prospective studies conducted with healthy people. Few RCTs (lasting 1-2years) have confirmed the benefits of following a Mediterranean diet on MetS risk in obese individuals, in those with the MetS or in those at CVD risk. The evidence, albeit limited, for a link between healthy diets based on other diet quality scores and the MetS supports a similar inverse association for the primary and secondary prevention of the MetS. CONCLUSION: Adhering to healthy diets such as the Mediterranean diet and/or national dietary guidelines can reduce inflammation and the MetS.

Association between dietary scores and 13-year weight change and obesity risk in a French prospective cohort.

BACKGROUND/OBJECTIVES: The relationship between diet quality and development of obesity is complex and unresolved. The aim of this study was to assess and compare the predictive value of six different dietary scores on both relative weight change and the risk of obesity after 13 years of follow-up in adults aged 45 years and older. SUBJECTS/METHODS: Six scores reflecting adherence to different nutritional recommendations (the French Programme National Nutrition Santé-Guideline Score (PNNS-GS), the Dietary Guidelines for Americans Index (DGAI), the Diet Quality Index-International (DQI-I), the Mediterranean Diet Scale (MDS), the relative Mediterranean Diet Score (rMED) and the Mediterranean Style Dietary Pattern Score (MSDPS)) were estimated in 3151 participants in the French SU.VI.MAX (SUpplémentation en VItamines et Minéraux AntioXydants) study. Associations of dietary scores with 13-year weight change were assessed through multivariate linear regression models, and obesity risk was analyzed with logistic regression, providing odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Except for the MSDPS, higher scores, that is, better adherence to nutritional guidelines or to a Mediterranean diet, were associated with lower weight gain in men (all P-value for trend <0.05). In addition, among men, ORs for becoming obese after 13 years associated with a 1 s.d. increase in dietary scores ranged from 0.63, 95% CI: 0.51, 0.78 for DGAI to 0.72, 95% CI: 0.59, 0.88 for MDS. These associations were weaker or not statistically significant in women. CONCLUSION: Overall, the six dietary scores predicted obesity risk equally well. Among French adults, strong adherence to dietary guidelines appears to be protective with regard to weight gain and obesity, especially in men.

[Kinetic properties of peroxidase from intact and virus-infected tobacco leaves]. / Kineticheskie svoistva peroksidazy, vydelennoi iz zdorovykh i zarazhennykh virusami rastenii tabaka.

The kinetic properties of peroxidase from tobacco leaves (var. Xanthie and Samsun) infected with various viruses (TMV, Xt and Xy, were compared. The enzyme from intact plant grown under similar conditions was used as control. The pH dependencies of the peroxidase activity for o-dianisidine peroxidation in infected and control plants were identical. Viral infection produces a dramatic effect on the kinetic properties of the enzyme: the KM values for o-dianisidine were decreased by 20-40% and those for H2O2 - by 30-40% in the case of the Samsun var. infected with TMV and Xanthie var. infected with a highly virulent strain of potato X-virus. The decrease of these values in plants infected with a weakly virulent strain of the virus was insignificant.

[Activity, isoenzyme composition, thermostability and molecular weight of peroxidase from intact and virus infected tobacco plant leaves]. / Aktivnost, izofermentnyi spektp, termostabil'nost' i molekuliarnyi vec peroksidazy, vydelennoi iz zdorovykh i zarazhennykh virusami rastenii tabaka.

The enzyme peroxidase was isolated from the leaves of the tobacco plant Xanthi (intact and infected with weakly (XY) and highly (XT) pathogenic strains of potato X-virus) and partially purified. The original extract (the 30,000 g supernatant) was purified by ammonium sulfate at 30--80% of saturation and by gel filtration through Sephadex G-25 and G-100 in 0.05 M tris-HCl buffer, pH 7.4 containing 17% sucrose. Disc electrophoresis revealed that both intact and infected plants contain 10 isoperoxidases. The electrophoregrams of isoenzymes from infected plants with the Rf values of 0.1, 0.48, 0.53 and 0.59 stained with benzidine produced a more intensive colouring as compared to the corresponding isoenzymes from intact plants. The total enzymatic activity for the plants infected with the XY and XT strains made up to 180% and 240% of that for the intact plants, respectively. The molecular weights of the peroxidase isoenzymes were found to be the same and equal to 40,000. Study of the thermostability at 60 degrees C and pH 7.0 showed that after 90 min the enzyme activity was 12.4% and 5.1% of the original one in intact and infected plants, respectively. The data obtained suggest that the activity, thermostability and synthesis of some peroxidase isoenzymes in tobacco plant leaves are affected by viral infection.

[Study of the antigenic structure of Salmonella by means of immunoelectrophoresis]. / Izuchenie antigennoi struktury sal'monell metodom immunoélektroforeza

The method of immunoelectrophoretic analysis was applied to the study of the antigenic structure of 180 freshly-isolated and laboratory cultures of salmonellae belonging to 29 serological types. A complicated set of specific and common antigens of bacteria was revealed in direct and cross experiments with the use of homologous and heterogenous antisera; immunophoregrams were drawn for each of the serological type under study. General regularities in immunophoretic, diffuse and serological characteristics of the individual antigens of salmonellae were established. It was shown that different serological types of salmonellae possessed surface K antigens along with the O and H antigens. On immunophoregrams K-antigens of salmonellae were revealed in the form of a bright precipitation arch in the central or the anode zone; O antigens gave a characteristic two-component precipitation line in the cathode zone of the phoregram.