Predictors of programme adherence and weight loss in women in an obesity programme using meal replacements

Objective: To explore predictors of programme adherence and weight loss in patients participating in a weight management programme using meal replacements (MR).Design: One hundred and fifty healthy obese women, age 48.5 years (s.d. = 8.3); weight, 97.6 kg (13.4); body mass index (BMI) 36.5 (3.7), participated in a longitudinal study with a 16-week acute weight loss phase (Phase 1) followed by 1 year of a trial of weight-loss maintenance (Phase 2). Energy intake during Phase 1 totaled 900 kcal (3.7 MJ) a day from a diet including two MR. Energy intake during Phase 2 consisted of either MR or a low-fat diet with a calculated energy deficit of 600 kcal/day (2.5 MJ).Methods: Weight, height and waist circumference were measured and body composition assessed by air plethysmography (Bodpod). Glucose and insulin were measured by standard immunoassays and insulin sensitivity assessed by homeostatic model assessment.Results: At the end of 16 weeks, 114 subjects (76%) completed Phase 1 and achieved a mean weight loss of 8.95 kg (3.38). Adherence to Phase 1 was predicted by weight loss over the first 2 weeks (p < 0.001). Weight loss during Phase 1 was predicted by initial weight and initial systolic blood pressure. Adherence to Phase 2 was not predicted by physiological measures. Weight loss maintenance in Phase 2 (not gaining more than 3% of the weight at start of phase 2) was predicted by cholesterol and triglyceride measured at the start of Phase 2 but otherwise was not predicted by the physiological measures. Initial insulin sensitivity did not predict weight loss in either phase.Conclusion: Participants whose weight loss over the first 2 weeks falls in the bottom third may need additional intervention if they are to continue in this type of programme. A battery of physiological measures at entry to a MR weight loss and maintenance programme explains only a very small proportion of the variation in weight loss

2-Amino-4,6-dimethyl­pyrimidin-1-ium 2,3,5-triiodo­benzoate 2,3,5-triiodo­benzoic acid monosolvate

In the crystal structure of the title compound, C6H10N3 +·C7H2I3O2 −·C7H3I3O2, two R 2 2(8) motifs are observed. One is generated by the inter­action of the 2-amino-4,6-dimethyl­pyrimidin-1-ium cation with the carboxyl­ate group of the 2,3,5-triiodo­benzoate anion via N—H⋯O hydrogen bonds. The other R 2 2(8) motif is formed by the inter­action of two centrosymmentrically related pyrimidine moieties through N—H⋯N hydrogen bonds. The two motifs combine to form a linear heterotetra­meric unit. Heterotetra­meric units are linked by a carbox­yl–carboxyl­ate O—H⋯O hydrogen bond (involving the O—H group of neutral 2,3,5-triiodo­benzoic acid and an O atom of the anion), forming a supra­molecular chain along the a axis. In addition, components are held by weak I⋯O interactions in the range 3.023 (5) to 3.382 (5) Å and I⋯I inter­actions in the range 3.6327 (7) to 4.0025 (8) Å

Pathway of human AS3MT arsenic methylation

A synthetic gene encoding human As(III) S-adenosylmethionine (SAM) methyltransferase (hAS3MT) was expressed, and the purified enzyme was characterized. The synthetic enzyme is considerably more active than a cDNA-expressed enzyme using endogenous reductants thioredoxin (Trx), thioredoxin reductase (TR), NADPH, and reduced glutathione (GSH). Each of the seven cysteines (the four conserved residues, Cys32, Cys61, Cys156, and Cys206, and nonconserved, Cys72, Cys85, and Cys250) was individually changed to serine. The nonconserved cysteine derivates were still active. None of the individual C32S, C61S, C156S, and C206S derivates were able to methylate As(III). However, the C32S and C61S enzymes retained the ability to methylate MAs(III). These observations suggest that Cys156 and Cys206 play a different role in catalysis than that of Cys32 and Cys61. A homology model built on the structure of a thermophilic orthologue indicates that Cys156 and Cys206 form the As(III) binding site, whereas Cys32 and Cys61 form a disulfide bond. Two observations shed light on the pathway of methylation. First, binding assays using the fluorescence of a single-tryptophan derivative indicate that As(GS)3 binds to the enzyme much faster than inorganic As(III). Second, the major product of the first round of methylation is MAs(III), not MAs(V), and remains enzyme-bound until it is methylated a second time. We propose a new pathway for hAS3MT catalysis that reconciles the hypothesis of Challenger ((1947) Sci. Prog., 35, 396-416) with the pathway proposed by Hayakawa et al. ((2005) Arch. Toxicol., 79, 183-191). The products are the more toxic and more carcinogenic trivalent methylarsenicals, but arsenic undergoes oxidation and reduction as enzyme-bound intermediates

2-Amino-4,6-dimethyl­pyrimidine–anthranilic acid (1/1)

In the title 1:1 adduct, C6H9N3·C7H7NO2, the crystal structure is stabilized by hydrogen bonds involving two different R 2 2(8) motifs. One of them is formed by the inter­action of 2-amino-4,6-dimethyl­pyrimidine (AMPY) with the carboxyl group of anthranilic acid (AA) through N—H⋯O and O—H⋯N hydrogen bonds, whereas the other is formed through the inter­action of two centrosymmetrically related pyrimidines involving N—H⋯N hydrogen bonds. These two combined motifs form a heterotetra­mer. The heterotetra­mer sheets are stacked into three-dimensional network

Design of co-crystals/salts of some Nitrogenous bases and some derivatives of thiophene carboxylic acids through a combination of hydrogen and halogen bonds

BACKGROUND: The utility of N-heterocyclic bases to obtain molecular complexes with carboxylic acids is well studied. Depending on the solid state interaction between the N-heterocyclic base and a carboxylic acid a variety of neutral or ionic synthons are observed. Meanwhile, pyridines and pyrimidines have been frequently chosen in the area of crystal engineering for their multipurpose functionality. HT (hetero trimers) and LHT (linear heterotetramers) are the well known synthons that are formed in the presence of pyrimidines and carboxylic acids. RESULTS: Fourteen crystals involving various substituted thiophene carboxylic acid derivatives and nitrogenous bases were prepared and characterized by using single crystal X-ray diffraction. The 14 crystals can further be divided into two groups [1a-7a], [8b-14b] based on the nature of the nitrogenous base. Carboxylic acid to pyridine proton transfer has occurred in 3 compounds of each group. In addition to the commonly occurring hydrogen bond based pyridine/carboxylic acid and pyrimidine/carboxylic acid synthons which is the reason for assembly of primary motifs, various other interactions like Cl…Cl, Cl…O, C–H…Cl, C-H…S add additional support in organizing these supermolecules into extended architectures. It is also interesting to note that in all the compounds π-π stacking occurs between the pyrimidine-pyrimidine or pyridine-pyridine or acid-acid moieties rather than acid-pyrimidine/pyridine. CONCLUSIONS: In all the compounds (1a-14b) either neutral O–H…N(pyridyl/pyrimidine) or charge-assisted N(pyridinium)-H…O(carboxylate) hydrogen bonds are present. The HT (hetero trimers) and LHT (linear heterotetramers) are dominant in the crystal structures of the adducts containing N-heterocyclic bases with two proton acceptors (1a-7a). Similar type supramolecular ladders are observed in 5TPC44BIPY (8b), TPC44BIPY (9b), TPC44TMBP (11b). Among the seven compounds [8b-14b] the extended ligands are linear in all except for the TMBP (10b, 11b, 12b). The structure of each compound depends on the dihedral angle between the carboxyl group and the nitrogenous base. All these compounds indicate three main synthons that regularly occur, namely linear heterodimer (HD), heterotrimer (HT) and heterotetramer (LHT)

Item parcels in structural equation modelling: an applied study in sport management

The purpose of this study is to describe the influences of different parceling strategies on goodness-of-fit measures and parameter estimates of a sport management structural model with latent variables. The use of small sample sizes to test models with a large number of parameters can produce poor fit indexes, mainly because many indicators tend to increase the chances of cross-loadings, which in turn reduce the common variance. Considering that in social and behavioral sciences is not quite easy to have access to large-enough samples, item parceling has been proposed as a remedy for this kind of situation. Using a theoretically-supported sport management model and real data, we compared total disaggregation model (items as indicators) with partial disaggregation models (parcels as indicators) and total aggregation model (summated score as the indicator). Results showed that different strategies of parceling could lead to very distinct conclusions. Implications for future studies using parceling in the field of sport management are discussed

Conformational changes in the Hepatitis B virus core protein are consistent with a role for allostery in virus assembly

In infected cells, virus components must be organized at the right place and time to ensure assembly of infectious virions. From a different perspective, assembly must be prevented until all components are available. Hypothetically, this can be achieved by allosterically controlling assembly. Consistent with this hypothesis, here we show that the structure of hepatitis B virus (HBV) core protein dimer, which can spontaneously self-assemble, is incompatible with capsid assembly. Systematic differences between core protein in dimer and capsid conformations demonstrate linkage between the intradimer interface and interdimer contact surface. These structures also provide explanations for the capsid-dimer selectivity of some antibodies and activity of assembly effectors. Solution studies suggest that the assembly-inactive state is more accurately an ensemble of conformations. Simulations show that allostery supports controlled assembly and results in capsids that are resistant to dissociation. We propose that allostery, as demonstrated in HBV, is common to most self-assembling viruses

An overview of sport in modern India

India is a land of immense cultural, religious and linguistic diversity. India has a strong tradition of sport participation, with modern sport such as cricket and tennis being attributed to the British colonisation era, and indigenous sport such as kabaddi and kho-kho making a comeback in the mainstream. The Ministry of Youth Affairs and Sport and the Sports Authority of India govern sport in India. These agencies have introduced programmes to attract the nation’s youth to participate in sporting events by providing them with financial and logistic support. With a growing middle class, the increase in disposable income and a new perspective towards being physically active, India’s participation in sport and recreation activities is on the rise. The advent of professional sporting leagues and the inspirational performances of Indian athletes ensure the country’s sporting tradition will continue to grow and flourish

Pathway of Human AS3MT ArsenicMethylation

A synthetic gene encoding human As(III) S-adenosylmethionine (SAM) methyltransferase (hAS3MT) was expressed, and the purified enzyme was characterized. The synthetic enzyme is considerably more active than a cDNA-expressed enzyme using endogenous reductants thioredoxin (Trx), thioredoxin reductase (TR), NADPH, and reduced glutathione (GSH). Each of the seven cysteines (the four conserved residues, Cys32, Cys61, Cys156, and Cys206, and nonconserved, Cys72, Cys85, and Cys250) was individually changed to serine. The nonconserved cysteine derivates were still active. None of the individual C32S, C61S, C156S, and C206S derivates were able to methylate As(III). However, the C32S and C61S enzymes retained the ability to methylate MAs(III). These observations suggest that Cys156 and Cys206 play a different role in catalysis than that of Cys32 and Cys61. A homology model built on the structure of a thermophilic orthologue indicates that Cys156 and Cys206 form the As(III) binding site, whereas Cys32 and Cys61 form a disulfide bond. Two observations shed light on the pathway of methylation. First, binding assays using the fluorescence of a single-tryptophan derivative indicate that As(GS)3 binds to the enzyme much faster than inorganic As(III). Second, the major product of the first round of methylation is MAs(III), not MAs(V), and remains enzyme-bound until it is methylated a second time. We propose a new pathway for hAS3MT catalysis that reconciles the hypothesis of Challenger ((1947) Sci. Prog., 35, 396?416) with the pathway proposed by Hayakawa et al. ((2005) Arch. Toxicol., 79, 183?191). The products are the more toxic and more carcinogenic trivalent methylarsenicals, but arsenic undergoes oxidation and reduction as enzyme-bound intermediates