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Antifreeze proteins (AFP) are produced by certain plants, animals, fungi and bacteria that enable them to survive upon extremely low temperature. Perennial rye grass, Lolium perenne, was reported to possess AFP which protects them from cold environments. In the present investigation, we isolated AFP gene from L. perenne and expressed it in tomato plants to elucidate its role upon chilling stress. The T1 transgenic tomato lines were selected and subjected to molecular, biochemical and physiological analyses. Stable integration and transcription of LpAFP in transgenic tomato plants was confirmed by Southern blot hybridization and RT-PCR, respectively. Physiological analyses under chilling conditions showed that the chilling stress induced physiological damage in wild type (WT) plants, while the transgenic plants remained healthy. Total sugar content increased gradually in both WT and transgenic plants throughout the chilling treatment. Interestingly, transgenic plants exhibited remarkable alterations in terms of relative water content (RWC) and electrolyte leakage index (ELI) than those of WT. RWC increased significantly by 3-fold and the electrolyte leakage was reduced by 2.6-fold in transgenic plants comparing with WT. Overall, this report proved that LpAFP gene confers chilling tolerance in transgenic tomato plants and it could be a potential candidate to extrapolate the chilling tolerance on other chilling-sensitive food crops.

Background: Carotenoids are antioxidant pigments that deposit in human tissues (e.g., skin, macula, and brain) upon dietary consumption. The health implications of skin carotenoids, which reflect overall dietary carotenoid consumption, have not been adequately studied in younger populations., Objectives: This work aimed to examine links between skin carotenoids and cognitive, language, and motor skills among toddlers. A secondary aim explored relationships between skin carotenoids and neurophysiologic outcomes of sensory memory [i.e., mismatch negativity (MMN)] and the functional integrity of the visual pathway [i.e., visual evoked potentials (VEPs)]., Methods: Toddlers aged 12-18 mo (n = 45) were included in a cross-sectional study. Skin carotenoids were measured with reflection spectroscopy via the Veggie Meter®. Cognitive, language, and motor skills were measured using the Bayley Scale of Infant and Toddler Development IV Screening Test (BSID-IV). MMN and VEPs were collected with an auditory oddball task and a pattern reversal task, respectively, using electroencephalography. Analyses adjusted for age, household income, highest level of parental education, and total carotenoid intake (mg/1000 kcal)., Results: Regression modeling revealed that skin carotenoids significantly related to cognition (β = 0.24; P = 0.04) and not to any other BSID-IV subsets. Neither MMN nor VEP outcomes significantly related to skin carotenoids., Conclusions: Greater skin carotenoids were selectively related to cognition, indicating that carotenoids may play a role in cognition in toddlers. Additional research is needed to understand links between skin carotenoids and specific domains of cognitive function and brain health in early life., (Copyright © 2024 American Society for Nutrition. Published by Elsevier Inc. All rights reserved.)

Objective: We investigated the relationship between nutrition literacy, diet quality, carotenoid status, and cognition., Methods: Adults aged 37.5 ± 17.0 years (n = 52) completed the 42-item Nutrition Literacy Assessment Instrument (NLit). The Dietary History Questionnaire III was analyzed to determine the Healthy Eating Index. Skin carotenoids were assessed as a diet quality biomarker. Selective attention, relational memory, and pattern separation abilities were assessed using the flanker, spatial reconstruction, and mnemonic similarity tasks, respectively. Statistical adjustments included age, sex, education, and body mass index., Results: No correlations were observed for NLit scores and NLit subscales with Healthy Eating Index and skin carotenoid status. However, the NLit's food label and numeracy subscale was related to greater pattern separation abilities (ρ = 0.33, r 2  = 0.11, P = 0.03)., Conclusions and Implications: Comprehension of food labels and numeracy information was associated with memory abilities. Future work is needed to test whether targeting working memory and attentional processes during memory retrieval in larger samples may facilitate the acquisition of nutrition knowledge., (Copyright © 2023 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.)

A rapid rise in population, extensive anthropogenic activities including agricultural practices, up-scaled industrialization, massive deforestation, etc. are the leading causes of environmental degradation. Such uncontrolled and unabated practices have affected the quality of environment (water, soil, and air) synergistically by accumulating huge quantities of organic and inorganic pollutants in it. Environmental contamination is posing a threat to the existing life on the Earth, therefore, demands the development of sustainable environmental remediation approaches. The conventional physiochemical remediation approaches are laborious, expensive, and time-consuming. In this regard, nanoremediation has emerged as an innovative, rapid, economical, sustainable, and reliable approach to remediate various environmental pollutants and minimize or attenuate the risks associated with them. Owing to their unique properties such as high surface area to volume ratio, enhanced reactivity, tunable physical parameters, versatility, etc. nanoscale objects have gained attention in environmental clean-up practices. The current review highlights the role of nanoscale objects in the remediation of environmental contaminants to minimize their impact on human, plant, and animal health; and air, water, and soil quality. The aim of the review is to provide information about the applications of nanoscale objects in dye degradation, wastewater management, heavy metal and crude oil remediation, and mitigation of gaseous pollutants including greenhouse gases., Competing Interests: Declaration of competing interest The authors have no competing interests to declare., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The UV-visible and fluorescence properties of hydroxy substituted benzothiazole derivatives change on interactions with zinc(II), cadmium(II) and mercury(II) ions. The binding of 2-(2'-hydroxyphenyl)benzothiazole is specific to zinc(II) over cadmium(II) and mercury(II). Similar type of interactions of zinc(II), cadmium(II) and mercury(II) with 2-(2',3',4'-trihydroxyphenyl)benzothiazole is observed in their UV-visible absorptions, whereas 2-(4'-hydroxyphenyl)benzothiazole shows interactions with mercury(II) over the other two ions., (Copyright 2010 Elsevier B.V. All rights reserved.)

The X-ray crystal structure is presented for a nitrogenase MoFe protein where the alpha subunit residue at position 70 (alpha-70(Val)) has been substituted by the amino acid isoleucine (alpha-70(Ile)). Substitution of alpha-70(Val) by alpha-70(Ile) results in a MoFe protein that is hampered in its ability to reduce a range of substrates including acetylene and N(2), yet retains normal proton reduction activity. The 2.3A structure of the alpha-70(Ile) MoFe protein is compared to the alpha-70(Val) wild-type MoFe protein, revealing that the delta methyl group of alpha-70(Val) is positioned over Fe6 within the active site FeMo-cofactor. This work provides strong crystallographic support for the previously proposed model that substrates bind and are reduced at a single 4Fe-4S face of the FeMo-cofactor and that when alpha-70(Val) is substituted by alpha-70(Ile) access of substrates to Fe6 of this face is effectively blocked. Furthermore the detailed examination of the structure provides the basis for understanding the ability to trap and characterize hydrides in the variant, contributing significantly to our understanding of substrate access and substrate reduction at the FeMo-cofactor active site of nitrogenase., (Copyright 2009 Elsevier Inc. All rights reserved.)

Objective: The purpose of this study was to describe pregnant patients with mitral stenosis who had intracardiac thrombosis in the absence of atrial fibrillation., Study Design: We reviewed the clinical course of 3 pregnant women with severe mitral stenosis and normal sinus rhythm who had clinically significant intracardiac thrombosis., Results: The first patient was examined at 21 weeks of gestation with embolic stroke that was the result of left atrial thrombus. A second patient was found to have a large left atrial thrombus that prevented the performance of balloon valvuloplasty. The third patient had left atrial clot that partially occluded the mitral valve orifice and led to the development of pulmonary edema that resulted in an emergent cesarean delivery and anoxic brain injury in the newborn infant., Conclusion: Pregnant patients with mitral stenosis in normal sinus rhythm can experience thromboembolic events that can be detrimental to both the mother and the fetus. Anticoagulation therefore should be strongly considered in this group.

Changes in regional cerebral blood flow (rCBF), associated with performance of an auditory verbal supraspan memory task, were studied in eight remitted DSM-III-R schizophrenic patients and eight pair-wise matched normal controls. Four positron emission tomography (PET) scans, using the [15O]-H2O technique, were acquired: two while subjects fixated a cross hair and two while performing a verbal free-recall supraspan memory task. Task performance showed typical patterns of recency and primacy effects in both groups; however, patients performed more poorly than controls on the primary (working) memory aspect of the task. Regions showing rCBF changes overlapped in both groups and were similar to those seen in previous studies of normals; however, patients had smaller increases in rCBF than controls in frontal and superior temporal cortical regions bilaterally. Our results suggest that remitted patients with schizophrenia demonstrate impairments of capacity-limited information processing, which may be related to metabolic dysfunction within a distributed network of brain structures, including the prefrontal and temporal cortical regions; however, dysfunction limited to the frontal cortex cannot be ruled out by the results of this experiment.

The bisphosphatase domain of rat liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase and a C-terminal 30 amino acid truncated form were expressed in high yield in Escherichia coli and purified to homogeneity. The separately expressed bisphosphatase domain and its C-terminal truncated form had kinetic properties similar to the bisphosphatase of the intact bifunctional enzyme, but their turnover numbers were fourfold higher. The truncated enzyme crystallized in space group P1 with two molecules per asymmetric unit. The determined cell dimensions are: a = 41.9 A, b = 43.5 A, c = 57.6 A, alpha = 95.2 degrees, beta = 99.3 degrees, and gamma = 106.2 degrees. These crystals diffract to 2.0 A resolution when exposed to synchrotron radiation and are suitable for crystallographic structure analysis.

One-dimensional nuclear Overhauser effect (NOE) in nuclear magnetic resonance spectroscopy along with stereochemically sound model building was employed to derive the structure of the hybrid poly(rA).poly(dT) in solution. Extremely strong NOE was observed at AH2' when AH8 was presaturated; strong NOEs were observed at TH2'TH2'' when TH6 was presaturated; in addition the observed NOEs at TH2' and TH2'' were nearly equal when TH6 was presaturated. There was no NOE transfer to AH3' from AH8 ruling out the possibility of (C-3'-endo, low anti chi approximately equal to 200 degrees to 220 degrees) conformation for the A residues. The observed NOE data suggest that the nucleotidyl units in both rA and dT strands have equivalent conformations: C-2'-endo/C-1'-exo, anti chi approximately equal to 240 degrees to 260 degrees. Such a nucleotide geometry for rA/dT is consistent with a right-handed B-DNA model for poly(rA).poly(dT) in solution in which the rA and dT strands are conformationally equivalent. Molecular models were generated for poly(rA).poly(dT) in the B-form based upon the geometrical constraints as obtained from the NOE data. Incorporation of (C-2'-endo pucker, chi congruent to 240 degrees to 260 degrees) into the classical B-form resulted in severe close contacts in the rA chain. By introducing base-displacement, tilt and twist along with concomitant changes in the backbone torsion angles, we were able to generate a B-form for the hybrid poly(rA).poly(dT) fully consistent with the observed NOE data. In the derived model the sugar pucker is C-1'-exo, a minor variant of C-2'-endo and the sugar base torsion is 243 degrees, the remaining torsion angles being: epsilon = 198 degrees, xi = 260 degrees, alpha = 286 degrees, beta = 161 degrees and gamma = 72 degrees; this structure is free of any steric compression and indicates that it is not necessary to switch to C-3'-endo pucker for rA residues in order to accommodate the 2'-OH group. The structure that we have proposed for the polynucleotide RNA-DNA hybrid in solution is in complete agreement with that proposed for a hexamer hybrid in solution from NOE data and is inconsistent with the heteronomous model proposed for the fibrous state.

Structural studies using 500 MHz 1H NMR spectroscopy on Bam H1 recognition site d(GGATCC)2 in solution at 19 degrees is reported. The resonances from the sugar ring and base protons have been assigned from the 2D-COSY and NOESY spectra. Analyses of the NOESY cross-peaks between the base protons H8/H6 and sugar protons H2'/H2", H3' reveal that the nucleotide units G2, A3 and C6 adopt (C3'-endo, chi = 200 degrees-220 degrees) conformation while G1, T4 and C5 exhibit (C2'-endo, chi = 240 degrees-260 degrees) conformation. NMR data clearly suggest that the two strands of d(GGATCC)2 are conformationally equivalent and there is a structural two-fold between the two A-T pairs. The above information and the NOESY data are used to generate a structural model of d(GGATCC)2. The important features are: (i) G1-G2 stack, the site of cleavage, shows an alternation in sugar pucker i.e. C2'-endo, C3'-endo as in a B-A junction, (ii) G2-A3 stack adopts a mini A-DNA, both the sugars being C3'-endo, (iii) A3-T4 stack, the site of two-fold, displays an A-B junction with alternation in sugar pucker as C3'-endo, C2'-endo, (iv) T4-C5 stack adopts a mini B-DNA both the sugars being C2'-endo and (v) C5-C6 stack exhibits a B-A junction with C2'-endo, C3'-endo sugar puckers. Thus, our studies demonstrate that conformational microheterogeneity with a structural two fold, is present in the Bam H1 recognition site.

The purpose of this study was to evaluate the usefulness of two-dimensional echocardiographic (2D echo) measurements in diagnosing right ventricular hypertrophy (RVH). These measurements of the right atrium and the ventricle were made in 15 patients with right ventricular hypertrophy and in 11 normal subjects and were as follows: right atrium long axis 2.13 +/- 0.42 vs 1.36 +/- 0.11 cm/m2 (p less than 0.001); right atrium short axis 2.78 +/- 0.60 vs 2.06 +/- 0.26 cm/m2 (p less than 0.001); right atrial area 8.81 +/- 2.79 vs 4.00 +/- 0.33 cm2/m2 (p less than 0.001); right ventricular long axis 4.65 +/- 0.64 vs 3.27 +/- 0.49 cm/m2 (p less than 0.001); and right ventricular area 13.02 +/- 3.64 versus 6.19 +/- 0.74 cm2/m2 (p less than 0.001). The 2D echo right atrial area and long axis had a sensitivity and specificity of 100 percent in the diagnosis of right ventricular hypertrophy. We conclude that 2D echo is useful in the diagnosis of right ventricular hypertrophy.

The molecular basis of fibril formation in Alzheimers disease was explored by electron micrographic and x-ray diffraction analysis of a series of synthetic peptides corresponding to portions of the amino acid sequence of beta protein and that of its putative precursor. A minimum 14 residue peptide was identified that formed typical amyloid fibrils under physiological conditions. Of these 14 residues, 10 were sufficient to give an identical 4.76 A and 10.6 A diffraction pattern as that recently described for isolated neurofibrillary tangles, amyloid plaque cores and leptomeningeal amyloid fibrils.

We have examined the effect of pH on diphtheria toxin conformation using intrinsic protein fluorescence and a new fluorescence quenching method. In aqueous solutions, fluorescence indicates toxin conformation undergoes a drastic change at low pH. This conformational change is closely associated with a switch from a hydrophilic conformation to a hydrophobic one, as judged by quenching-detected detergent binding. In the absence of NaC1 these changes occur around pH 4-4.5. However, in 150 mM NaCl the conformational change occurs in the pH 5-5.5 range, close to the pH the toxin is expected to encounter in endosomes and lysosomes. Therefore, the conformational change observed at low pH is likely to be physiologically significant.