Eating context and ultraprocessed food consumption among UK adolescents.

We aimed to evaluate the association between eating context patterns and ultraprocessed food consumption at two main meal occasions in a representative sample of UK adolescents. Data were acquired from 4-d food records of adolescents aged 11-18 years, who participated in the 2014-2016 UK National Diet and Nutrition Survey (n 542). The eating context was assessed considering the location of the meal (lunch and dinner) occasion, the individuals present, whether the television was on and if the food was consumed at a table. Ultraprocessed foods were identified using the NOVA classification. Exploratory factor analysis was used to identify eating context patterns for lunch and dinner. Linear regression models adjusted for the covariates were utilised to test the association between eating context patterns and the proportion of total daily energy intake derived from ultraprocessed foods. Their contribution was about 67 % to energy intake. Three patterns were retained for lunch ('At school with friends', 'TV during family meal' and 'Out-of-home (no school)'), and three patterns were retained for dinner ('Watching TV alone in the bedroom', 'TV during family meal' and 'Out-of-home with friends'). At lunch, there was no significant association between any of the three patterns and ultraprocessed food consumption. At dinner, the patterns 'Watching TV alone in the bedroom' (coefficient: 4·95; 95 % CI 1·87, 8·03) and 'Out-of-home with friends' (coefficient: 3·13; 95 % CI 0·21, 6·14) were associated with higher consumption of ultraprocessed food. Our findings suggest a potential relationship between the immediate eating context and ultraprocessed food consumption by UK adolescents.

Potential reductions in ultra-processed food consumption substantially improve population cardiometabolic-related dietary nutrient profiles in eight countries.

BACKGROUND AND AIMS: The negative effect on dietary nutrient profiles is the most obvious mechanism explaining the higher risk of cardiometabolic diseases associated with increased dietary share of UPF observed in large cohort studies. We estimate the proportion of diets with excessive energy density, excessive free sugars or saturated fat contents and insufficient fiber that could be avoided, if UPF consumption was reduced to levels among lowest consumers across eight countries, as well as the proportion of diets with multiple inadequacies. METHODS AND RESULTS: Using nationally-representative cross-sectional surveys from Brazil (2008-09), Chile (2010), Colombia (2005), Mexico (2012), Australia (2011-12), the UK (2008-16), Canada (2015), and the US (2015-16), inadequate energy density (≥2.25 kcal/g) or contents of free sugars (>10% of total energy intake), saturated fats (>10% of total energy intake) and fiber (<25 g/2000 kcal) population attributable fractions were quantified. Substantial reductions in nutrient inadequacies would be observed ranging from 50.4% in Chile to 76.8% in US for dietary energy density, from 15.5% in Colombia to 68.4% in Australia for free sugars, from 9.5% in Canada to 35.0% in Mexico for saturated fats, and from 10.3% in UK to 37.9% in Mexico for fiber. Higher reductions would be observed for diets with multiple nutrient inadequacies: from 27.3% in UK to 77.7% in Australia for ≥3 and from 69.4% in Canada to 92.1% in US, for 4 inadequacies. CONCLUSIONS: Lowering dietary contribution of UPF to levels among country-specific lowest consumers is a way to improve population cardiometabolic-related dietary nutrient profiles.

Risk and protective behaviors for chronic non-communicable diseases among Brazilian adults.

OBJECTIVES: This study aimed to analyze behavioral patterns of protective and risk factors for chronic non-communicable diseases (NCDs) among adults and to explore the association between these patterns and sociodemographic characteristics using data from the National Health Survey 2013. STUDY DESIGN: This was a cross-sectional study. METHODS: This is a population-based study, nationwide, of individuals aged ≥18 years (n = 60,202). The sampling process used was grouping with three selection stages: census sector, households, and individuals. The factor analysis by principal component was used to identify behavioral patterns of protective and risk factors for NCDs. Linear regression was used to explore the association between patterns and sociodemographic characteristics. RESULTS: Two behavioral patterns were identified: a 'protective pattern' featured by consumption of vegetable, fruits/natural fruit juice, and low-fat milk and recommended physical activity practice during leisure time; and a 'risk pattern' characterized by consumption of high-fat meat and soft drinks, alcohol abuse, and smoking habit. Adherence to the protective pattern was associated with older White women who had higher levels of education, were economically active, and lived in the urban areas of the country. Younger, economically active men living in the urban areas were associated with the risk patterns. CONCLUSIONS: Two behavioral patterns for NCDs have been identified and are distributed non-randomly in the adult Brazilian population. These findings are expected to contribute to better targeting health promotion and prevention of NCDs.

Role of T cell recruitment and chemokine-regulated intra-graft T cell motility patterns in corneal allograft rejection.

Keratoplasty is the primary treatment to cure blindness due to corneal opacification. However, immune-mediated rejection remains the leading cause of keratoplasty failure. Here, we utilize an in vivo imaging approach to monitor, track, and characterize in real-time the recruitment of GFP-labeled allo-specific activated (Bonzo) T cells during corneal allograft rejection. We show that the recruitment of effector T cells to the site of transplantation determined the fate of corneal allografts, and that local intra-graft production of CCL5 and CXCL9/10 regulated motility patterns of effector T cells in situ, and correlated with allograft rejection. We also show that different motility patterns associate with distinct in vivo phenotypes (round, elongated, and ruffled) of graft-infiltrating effector T cells with varying proportions during progression of rejection. The ruffled phenotype was characteristic of activated effectors T cells and predominated during ongoing rejection, which associated with significantly increased T cell dynamics within the allografts. Importantly, CCR5/CXCR3 blockade decreased the motility, size, and number of infiltrating T cells and significantly prolonged allograft survival. Our findings indicate that chemokines produced locally within corneal allografts play an important role in the in situ activation and dynamic behavior of infiltrating effector T cells, and may guide targeted interventions to promote graft survival.

Graft-vs.-host-associated immune suppression is activated by recognition of allogeneic murine I-A antigens.

Several combinations of F1 hybrid mice were injected intravenously with parental spleen cells to determine the minimal H-2 differences between F1 and parent that are necessary to induce graft-vs.-host-associated immune suppression (GVH-associated suppression). 7-14 d after injection, the spleens of the F1 mice were tested for cytotoxic T lymphocyte potential by in vitro sensitization against trinitrophenyl-self and H-2 alloantigens. The results indicate that parental T lymphocytes must recognize I-A allogeneic determinants of the F1 recipient in order to induce suppression. Recognition of K or D alone or D with I region products other than I-A did not induce suppression. The recognition of I region without K and/or D and even the I-A difference between C57BL/6 and the B6.Cbm12 mutation resulted in immune suppression that was as potent as that resulting from the recognition of K, D, and I together. The possible significance of this function for I-A antigens is discussed with respect to three clinical examples of immune suppression for which this phenomenon may be relevant.

Regulation of T-cell-mediated lympholysis by the murine major histocompatibility complex. I. Preferential in vitro responses to trinitrophenyl-modified self K- and D-coded gene products in parental and F1 hybrid mouse strains.

Spleen cells from H-2b,k,d C57Bl/10 congenic mice were sensitized in vitro to trinitrobenzenesulfonate (TNBS)-modified autologous spleen cells. Cold target competition studies at the lytic phase demonstrated three distinct patterns of cytotoxic responsiveness: (a) H-2b spleen cells generated approximately equivalent CTL responses against Kb and Db modified self products, (b) H-2d spleen cells generated preferential responses against Dd modified self products, and (c) H-2k spleen cells generated cytotoxic responses which could only be detected against Kk self products in association with TNP. F1 spleen cells were sensitized against autologous TNBS-treated cells. The results showed that, although H-2b parental cells generated approximately equivalent Kb-TNP- and Db-TNP-specific CTL, the presence of the H-2b haplotype did not result in the generation of (a) Dk-TNP CTL response by (H-2b x H-2k) spleen cells, nor (b) a Db CTL response by (H-2b x H-2a) F1 spleen cells. Additionally, (H-2d x H-2k) F1 cells failed to generate detectable Dd-TNP-specific CTL, although H-2d parental cells generated D-regional-specific CTL. The findings demonstrated that these F1 response patterns paralleled those of the H-2k and H-2a parents, i.e. weak or no D-region TNP-specific CTL were induced. Because (H-2d x H-2a) F1 responders stimulated with H-2d TNBS-treated cells did generate good Dd TNP responses, the results illustrated that the presence of responder genes was not sufficient to result in a D-region TNP CML. It is suggested that the absence of Kk alleles on the stimulating population is necessary for the generation of D-region TNP CTL in these F1's. Mechanisms which could account for these response patterns in parental F1 mice are discussed including immunodominance, suppression, T-cell response , and Ir-gene defects.

Regulation of T-cell-mediated lympholysis by the murine major histocompatibility complex. II. Control of cytotoxic responses to trinitrophenyl-K and -D self products by H-2K- and H-2D-Region genes.

An H-2K/IA recombinant mouse strain was used to map the genes within the H-2 complex which determine the ability to respond in cell-mediated lympholysis (CML) to low doses of trinitrophenyl-self (TNP-self). It was found that gene(s) which map to the K region are involved in regulation of CML response to low-dose TNP-self. It was also found that CML response to TNP recognized in association with H-2Dq was not detectable in this recombinant. These findings are discussed with respect to the involvement of the H-2K and H-2D regions by structural and/or regulator gene functions.

Role of self and foreign antigenic determinants in allogeneic and self-restricted cytotoxic T cell recognition.

Murine spleen cells were sensitized in vitro to H-2 disparate allogeneic spleen cells and assayed on syngeneic target cells conjugated with the trinitrophenyl (TNP)-self or the fluorescein isothiocyanate (FITC)-self haptens, or on syngeneic target cells expressing the male H-Y antigen (H-Y self). The results indicated that allo-induced cytotoxic T lymphocytes (CTL) contained effectors that lysed both hapten-self but not H-Y self targets. Furthermore, it was demonstrated that separate populations of those allogeneic CTL were responsible for the lysis of TNP-self and FITC-self targets. This study also showed that cytotoxic effectors generated against the H-Y antigen with lytic activity equal to or greater than that of an allogeneically induced CTL response were unable to lyse hapten-self targets. These findings provide the first evidence that H-2 alloantigens may be unique in their ability to induce effectors that lyse hapten-conjugated autologous targets. These observations are discussed with respect to the self and foreign antigenic determinants involved in allogeneic and self-restricted CTL models.

Correlation of suppressor cell development in parental and F1 hybrid mouse strains with the growth of a parental tumor in vivo.

Parental AKR/J, and AKB6F1 and AKD2F1 hybrid mice were injected subcutaneously with a spontaneously arising AKR/J tumor. The highly responsive AKB6F1 strain never exhibited any depression of immune functioning during the course of tumor growth and regression. The (AKR/J) intermediately responsive strain, while able to generate a successful anti-tumor response, did display a transient reduction of immunological capability, but only during the period tumor growth and not during tumor regression. Cells able to suppress antibody, but not cell-mediated responses, were found. The unresponsive AKD2F1 strain was characterized by both a marked depression of immune responsiveness, as well as the generation of suppressor cells to both antibody, and later, cell-mediated responses. Depression of immune responsiveness, and the generation of suppressor cells, appeared to correlate with the strength or weakness of the anti-tumor response in these strains of mice.

The role of cell-mediated cytotoxicity in acute GVHD after MHC-matched allogeneic bone marrow transplantation in mice.

The role of cell-mediated cytotoxicity in the complex pathophysiology of graft-versus-host disease (GVHD) has remained poorly defined for several decades. We transplanted T cells from Fas-ligand (FasL)-defective and perforin-deficient mutant donor mice into lethally irradiated MHC-matched allogeneic recipient mice to characterize the role of cell-mediated cytotoxicity in GVHD. Although recipients of allogeneic FasL-defective donor T cells underwent severe GVHD-associated cachexia, they exhibited only minimal signs of hepatic and cutaneous GVHD pathology. Recipients of perforin-deficient allogeneic donor T cells developed signs of acute GVHD, but the time of onset was significantly delayed. These findings demonstrate that Fas-mediated anti-recipient cytotoxicity may be critical for the development of hepatic and cutaneous GVHD, but is not required for GVHD-associated cachexia. In addition, perforin-mediated anti-recipient cytotoxicity appears to play an important role in the kinetics of GVHD pathophysiology, but is not required for GVHD-associated tissue damage.

Involvement of H-2L gene products in virus-immune T-cell recognition. Evidence for an H-2L-restricted T-cell response.

The H-2L locus is closely linked to H-2D and codes for antigenic specificities present on a 45,000 mol wt glycoprotein that is distinct from the molecule which bears the D region private specificity. It was found that BALB/c-H-2db mice, which lack detectable cell-surface H-2L gene products, were able to generate influenza- and vaccinia-immune cytotoxic T cells which lyse D region-compatible target cells, although they have been reported to be incapable of making a similar response to ectromelia virus (7). Thus, the lack of H-2L antigenic specificities does not produce a general loss of responsiveness for other viruses even when a highly cross-reactive pox virus (vaccinia) was studied. Antisera-blocking experiments utilizing sera specific for either L or D molecules indicated that BALB/c mice generate influenza virus-immune cytotoxic T-cell subsets which independently recognize H-2L and H-2D gene products in association with viral antigens. These results are the first indication that products of the H-2L locus can operate analogously to H-2K/D gene products in virus-immune T-cell recognition.

Trinitrophenyl modification of H-2k and H-2b spleen cells results in enhanced serological detection of Kk-like determinants.

Several anti-H-2Kk but not anti-H-2Dd monoclonal antibodies (mAb) exhibited enhanced binding to B10.A murine spleen cells after modification of the cells with trinitrobenzene sulfonate (TNBS). The number of antibody molecules bound to TNP-modified B10.A spleen cells increased by a factor of two or more. The same anti-2Kk mAb that exhibited enhanced binding to modified B10.A cells did not bind to unmodified C57BL/10 spleen cells, as expected, but did bind to TNP-modified C57BL/10 spleen cells. This TNP-dependent binding was not a result of cross-reactions with cell surface TNP groups nor with Fc receptors. TNP modification of a variant cell line that does not express class I H-2 products did not result in enhanced binding by these mAb. These findings can account for preferential recognition of TNP-Kk by B10.A and B10.BR CTL, and also for cross-reactive lysis by C57BL/10 CTL stimulated by C57BL/10-TNP against unmodified H-2Kk targets.

Platinum-like behavior of tungsten carbide in surface catalysis.

Tungsten carbide catalyzes the formation of water from hydrogen and oxygen at room temperature, the reduction of tungsten trioxide by hydrogen in the presence of water, and the isomerization of 2,2-dimethylpropane to 2-methylbutane. This catalytic behavior, which is typical of platinum, is not exhibited at all by tungsten. The surface electronic properties of the latter are therefore modified by carbon in such a way that they resemble those of platinum.

Monoclonal antibodies to the common gamma-chain as cytokine receptor antagonists in vivo: effect on intrathymic and intestinal intraepithelial T lymphocyte development.

Mice lacking a functional gamma c subunit of cytokine receptors exhibit profound defects in the development of multiple lymphoid lineages. To investigate the role of gamma c-dependent cytokines in T cell development, the phenotype of developing T cells was compared in interleukin (IL)-7Ralpha-deficient mice and anti-gamma c mAb-treated chimeric mice reconstituted with adult bone marrow cells or subsets of pro-T cells. These studies indicate that gamma c contributes to T cell development at multiple stages of pro-T cell maturation and that IL-7/IL-7R is the primary cytokine for thymic-dependent T cell development. However, our data also implicate other gamma c-dependent cytokines during thymic T cell development. By contrast, substantial intestinal intraepithelial lymphocytes (IEL) development was observed in the intestinal intraepithelium in both types of mice. Analysis of IL-7Ralpha-deficient mice indicates that the IL-7/IL-7R system is critical only for the development of TCR gammadelta+ IEL. However, the inhibitory activity of the anti-deltac mAb in the chimeric mouse model suggests that additional gamma cutilizing cytokines regulate the development of the remaining subsets of IEL.

Hapten specific TNP-reactive cytotoxic effector cells using epidermal cells as targets.

Epidermal spongiosis, invasion of mononuclear cells into the epidermis, and epidermal cell destruction are regular findings in allergic contact dermatitis. The mechanism(s) by which these changes occur is not known. We have examined the possibility that some of the pathological changes observed in allergic contact dermatitis could be accounted for by invasion of the epidermis by cytotoxic effector cells which recognize hapten-modified self-antigens and therein cause epidermal cell destruction. C3H and BALB/c mice were sensitized by epicutaneously applied 7% trinitrochlorobenzene (TNCB). 14 days later spleen cells from these mice were stimulated in vitro to trinitrophenylated- (TNP-conjugated) syngeneic spleen cells and their responses were compared to the in vitro responses of spleen cells from unsensitized mice. After 5 days of culture, effector cell activity was assayed on 51Cr-labeled TNP-conjugated syngeneic epidermal cells and on unconjugated epidermal cells. Cytotoxic activity was detected in the spleens of both mouse strains, but was greater in the C3H than the BALB/c strain. The cytotoxic effector cell activity was hapten specific in that spleen cells from TNCB sensitized mice did not cause lysis of fluorescein isothiocyanate (FITC) conjugated epidermal cells and spleen cells from FITC sensitized mice did not cause lysis of TNP-conjugated epidermal cells. No significant cytotoxic activity was detected on unconjugated epidermal cells. These findings suggest that destruction of the epidermis in allergic contact dermatitis may be contributed to by sensitized cytotoxic effector cells.

1,25-Dihydroxyvitamin D3 antagonizes interferon-gamma-induced expression of class II major histocompatibility antigens on thyroid follicular and testicular Leydig cells.

Interferon-gamma (IFN gamma) induces production and expression of major histocompatibility complex class II molecules on both marrow-derived and nonbone marrow-derived cell types. 1,25-Dihydroxyvitamin D3 [1,25-(OH)2D3], a seco-steroid derived from vitamin D3, has previously been reported to enhance such expression alone or together with IFN gamma on a number of monocyte/macrophage tumorigenic lines. In contrast, the present studies have found that 1,25-(OH)2D3 inhibited the ability of IFN gamma to induce class II antigen expression on nontransformed rat thyroid follicular epithelial cells (FRTL-5) and mouse testicular Leydig cells (TM3). Although 1,25-(OH)2D3 inhibited the induction of both IA and IE class II locus products, IFN gamma augmentation of class I major histocompatibility complex antigens was not affected. 1,24-(OH)2D3 and 24,25-(OH)2D3 also inhibited class II induction by IFN gamma. Notably, the relative inhibitory ability of these compounds paralleled the strength of their binding affinities for the 1,25-(OH)2D3 receptor, indicating that this antagonistic effect probably requires receptor-ligand interaction. Other steroid hormones, such as hydrocortisone or testosterone, had no inhibitory effect on IFN gamma-induced class II expression on Leydig cells. Additionally, the failure of indomethacin to reverse the effect of 1,25-(OH)2D3 and the finding that exogenous prostaglandin E2 did not inhibit class II induction in these cells indicated that prostaglandins are probably not responsible for this anti-IFN gamma activity. In total, these results suggest that an endocrinological mediator is capable of inhibiting class II induction on resident endocrine tissue populations and, therefore, could help to diminish local CD4+ T-cell recognition of these cells.

The use of primed cytotoxic T lymphocytes as a highly sensitive and accurate method for the detection of MHC disparate allogeneic cells.

The present studies have investigated the use of primed cytotoxic T cells (CTL) for the purpose of detecting the presence of an MHC disparate allogeneic cell population. The findings indicate that restimulation of primed CTL in the presence of activated T cell supernatants is an extremely sensitive method capable of detecting one allogeneic cell within a population containing 10,000 total cells (0.01%). In addition, this primed lymphocyte cytotoxicity assay (PLCA) was shown to be at least as accurate as flow cytometric analysis in determination of low numbers and percentages of allogeneic cells within the cell population being examined. Furthermore, the nature of the allogeneic mononuclear population did not influence the sensitivity or accuracy of this method. To examine this method's applicability for the detection of chimeric populations in vivo, spleen and thymic tissue from neonatally tolerized animals were examined by PLCA analysis. Allogeneic cells were readily detected in 100% of individual host spleen and thymuses tested. In total, the results showed that the PLCA is a highly reproducible and accurate method for the detection of extremely low numbers of allogeneic cells. This approach should be useful to monitor the presence of foreign cells in experimental and clinical situations in which individuals are exposed to allogeneic cell populations.

Thiol groups on the surface of anaerobic parasitic protozoa.

Evidence is presented that Giardia lamblia and Entamoeba histolytica, phylogenetically unrelated aerotolerant anaerobes, have crucial thiol groups on or easily accessible to their external surface. Both parasites were killed by three structurally unrelated thiol-blocking reagents which penetrate intact cells poorly or not at all. The parasites were protected from p-chloromercuribenzenesulfonic acid (10-100 microM) by cysteine or by reduced glutathione. Killing was arrested with identical kinetics by addition of either cysteine (which quickly penetrates the cells) or bovine serum albumin (which does not penetrate intact cells) at various times after p-chloromercuribenzenesulfonic acid, indicating that the reactive site may be on the outer surface of the cell. Proteins lacking cysteine did not protect. Sensitivity of three other protozoa to p-chloromercuribenzenesulfonic acid was also tested. Trichomonas vaginalis (anaerobic) was at least as sensitive as E. histolytica and G. lamblia, while Crithidia fasciculata and Paramecium tetraurelia (both aerobic) were less sensitive. Thiol groups on the G. lamblia surface were demonstrated directly by fluorescence-activated cell sorter analysis of trophozoites which had been modified with a thiol-specific hapten, N-iodoacetyl-N'-(5-sulfonic-1-naphthyl)ethylenediamine and reacted with fluorescent antibody to this hapten.

The ability of murine cytomegalovirus and class I major histocompatibility complex-disparate parental cells to induce alterations characteristic of severe graft-versus-host reactions.

The present studies were undertaken to examine the ability of a viral pathogen to enhance immune alterations associated with parent----F1 graft-versus-host reactions (GvHR) across defined donor/recipient MHC genetic disparities. Murine cytomegalovirus (MCMV) was administered concurrently with a parental lymphoid inoculum into unirradiated F1 recipients in strain combinations limiting allogeneic differences to the entire MHC complex (class I/II), the H-2K region (class I), or H-2IA (class II) regions only. Alterations previously found to be associated with GvHR involving changes in the expression of Ly-6, Lyt-2, and L3T4 were examined to characterize the effects of MCMV. Mice receiving low numbers of class I/II-disparate parental cells or MCMV alone failed to exhibit significant GvHR-associated changes. In contrast, introduction of cells and virus resulted in marked alterations characteristic of F1 recipients injected with a large parental cell inoculum alone. Concurrent virus and parental cells could also induce marked changes when administered across differences involving only a class I-disparate--but not class II-disparate only--P----F1 combination. In addition to the phenotypic changes observed during the concurrent virus and class I GvHR, markedly reduced spleen cell proliferative activity and associated weight loss and mortality appeared to indicate that virus had enhanced this reaction. In total, these findings demonstrated that a donor/recipient class I MHC difference was necessary for virus and parental cells to induce the changes observed, and thus not all donor/recipient antigenic differences will result in a similar virus-induced effect. The results are discussed with respect to the potential mechanisms that may account for the apparent exacerbation of GvHR-associated alterations.

Virus-associated immune responses in mice undergoing GVHR exacerbated by concurrent MCMV infection.

It has been proposed that virus-induced immune responses early postinjection of donor cells can result in the exacerbation of GVH reactions. Previously, we and others have shown that introduction of MCMV together with class I-disparate donor cells results in the development of severe GVH reactions. The present studies were performed to examine the nature of the immune responses induced by concurrent MCMV infection early during GVHR. Within 3 days and continuing through day 10 postinjection, spleens from recipients of virus + GVHR inocula exhibited enhanced cytotoxic activity against YAC-1 target cells effected by a Thy1-Lyt-2-ASGM1+NK1.1+ population. Notably, within one week after virus and GVHR injection, sera from those animals were found to contain specific anti-MCMV IgM antibody at levels comparable to those induced in mice injected only with virus. However, in contrast to recipients of MCMV alone, sera from virus + GVHR animals never contained anti-MCMV IgG antibody. To determine the effect of virus on a discrete donor antihost response, antihost cytotoxic activity was examined. By 7 days postinjection, the spleens of virus + GVHR but not GVHR-only recipients contained marked levels of specific antihost cytotoxic activity, mediated by a Thy1+Lyt-2+ASGM1+NK1.1- population. In total, these findings support the hypothesis that early virus-induced immune responses may promote the development of severe graft-versus-host responses including the enhancement of donor antihost specific cytotoxic T cells.