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1.
RSC Adv ; 12(37): 24397-24411, 2022 Aug 22.
Article in English | MEDLINE | ID: mdl-36128520

ABSTRACT

Porous organic cages have shape persistent cavities which provide a suitable platform for encapsulation of guest molecules with size suitably fitting to the cavity. The interactions of the guest molecule with the porous organic cage significantly alter the properties of the guest molecule. Herein, we report the effect of encapsulation on the kinetics of various organic transformations including 2 + 4 cycloaddition, 1,5-sigmatropic, 6π-electrocyclization, ring expansion, cheletropic, dyotropic, trimerization and tautomerization reactions. Non-bonding interactions are generated between the CC2 cage and encapsulated species. However, the number and nature/strength of interactions are different for reactant and TS with the CC2 cage and this difference detects the reaction to be accelerated or slowed down. A significant drop in the barrier of reactions is observed for reactions involving strong interactions of the transition state within the cage. However, for some reactions such as the Claisen rearrangement, reactants are stabilized more than the transition state and therefore an increase in activation barrier is observed. Furthermore, non-covalent analyses of all transition states (inside the cage) confirm the interaction between the CC2 cage and substrate. The current study will promote further exploration of the potential of other porous structures for similar applications.

2.
Chemosphere ; 258: 127353, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32554014

ABSTRACT

Extensive use of antibiotic results in significant antibiotics pollution in the environment. Main objective of this study was to gain insight into potential impacts of antibiotics on plant physiological growth and nutritional composition, and stress alleviation through application of different organic amendments. Effects of five antibiotics (ciprofloxacin, levofloxacin, ofloxacin, amoxicillin and ampicillin) were observed in the presence of three organic amendments (rice husk, farmyard manure and poultry litter) with rice (Oryza sativa L.) as a model plant. Organic amendments were mixed with soil (@ 5 g kg-1) and after three weeks, antibiotics were applied (@10 mg kg-1) and plants were allowed to grow for four months. After which plants were harvested and physical growth parameters (root/shoot length, biomass) and nutritional composition (grain protein content, carbohydrates, phosphorous and iron) were monitored. It was observed that germination rate, seedling root/shoot length, seedling biomass and vigor index were negatively impacted. The application of organic amendments alleviated antibiotic stress on seedling dry biomass, length and vigor index by 1.8-, 3.1- and 2.5-folds, respectively as compared to the antibiotic controls. Concentrations of phosphorous, iron, carbohydrates and proteins were decreased by 5.3-, 1.3-, 1.4- and 1.6-folds upon application of antibiotics. Rice husk was the most effective treatment in case of physical growth parameters and alleviating antibiotics' induced genotoxicity. Whereas, poultry litter had the highest positive effect on nutritional composition of plants. In general, the application of organic amendments alleviated the phytotoxicity as well as genotoxicity in plants under antibiotics stress.


Subject(s)
Anti-Bacterial Agents/toxicity , Oryza/physiology , Soil Pollutants/toxicity , Anti-Bacterial Agents/metabolism , Biomass , Environmental Pollution , Germination , Manure , Oryza/metabolism , Seedlings/metabolism , Soil , Soil Pollutants/analysis
3.
Pediatr Transplant ; 22(3): e13130, 2018 05.
Article in English | MEDLINE | ID: mdl-29473271

ABSTRACT

Neutropenia has been reported in pediatric heart transplant recipients, but its association with infectious morbidity and mortality is unknown. We sought to determine neutropenia's prevalence and impact on infection, rejection, and survival. A retrospective analysis of pediatric heart transplant recipients from March 2005 to August 2015 was performed. Demographics, medications, infection, and rejection data were collected. Of 142 pediatric heart transplant recipients, 77 (54.2%) developed neutropenia within 4.7 months [3.3-12.1 months] of transplant. In all patients, the adjusted 5-year cumulative incidence of neutropenia was 30.2%. Fifty-one patients (66.2%) had recurrent neutropenia. Six of 14 tested had positive antineutrophil antibodies. Medications associated with neutropenia were decreased in 15 (19.5%) and discontinued in 42 (54.4%) patients with no change in 1-year rejection rates compared to published data. Fifteen patients developed infection within 30 days of neutropenia and two from 30 days to 1 year, with an infection rate similar to the non-neutropenic group. There was no significant difference in survival, ANC, rate of rejection or PTLD in neutropenic patients with and without infection at median follow-up (5.5 years). Neutropenia is common in pediatric heart transplant recipients. Neutropenia had <20% risk of associated infection, similar to non-neutropenic patients. Infection in neutropenic patients did not increase mortality.


Subject(s)
Heart Transplantation , Neutropenia/etiology , Adolescent , Child , Child, Preschool , Female , Follow-Up Studies , Graft Rejection/epidemiology , Graft Rejection/etiology , Graft Survival , Heart Transplantation/mortality , Humans , Incidence , Infant , Infections/epidemiology , Infections/etiology , Male , Neutropenia/epidemiology , Postoperative Complications , Prevalence , Retrospective Studies , Survival Analysis
4.
Birth Defects Res ; 109(1): 38-48, 2017 01 20.
Article in English | MEDLINE | ID: mdl-27905191

ABSTRACT

BACKGROUND: The United States Public Health Service recommends that all women of reproductive age consume 400 µg of folic acid daily to prevent major neural tube defects. Hispanics have the highest prevalence of neural tube defects compared with other race/ethnic groups. We studied prevalence of preconception folic acid supplement use, and its association with race/ethnicity among pregnant women in Georgia. METHODS: Using state-wide population-based data from 2009 to 2011 Georgia Pregnancy Risk Assessment Monitoring System, we examined the prevalence of preconception folic acid supplement use among pregnant women aged 18 to 45 years. We conducted multivariable logistic regression and estimated adjusted odds ratios and 95% confidence intervals to examine the association between race/ethnicity and supplemental folic acid use among study participants. RESULTS: Overall, 25% of all participants reported taking folic acid supplements daily before conception. Only 21% of Hispanic women reported preconception folic acid supplement use. Hispanic women were twice as likely to not take folic acid supplements (adjusted odds ratio = 2.15; 95% confidence interval, 1.35-3.40) compared with non-Hispanic whites, after controlling for maternal age, parity, pregnancy intention, knowledge that folic acid prevents birth defects, and preconception smoking and exercise. CONCLUSION: Hispanics are a growing population in the United States with an expected 14 million women of child-bearing age by 2020, and the prevalence of preconception folic acid supplement use is low in this group with a high risk of neural tube defects. Promotion of voluntarily fortified corn masa flour can lower neural tube defects in Hispanics. Mandatory corn masa fortification will be a more effective public health policy.Birth Defects Research 109:38-48, 2017. © 2016 Wiley Periodicals, Inc.


Subject(s)
Folic Acid/metabolism , Folic Acid/therapeutic use , Neural Tube Defects/diet therapy , Adolescent , Adult , Anencephaly/diet therapy , Anencephaly/epidemiology , Anencephaly/prevention & control , Dietary Supplements/statistics & numerical data , Ethnicity/genetics , Female , Food, Fortified , Georgia/epidemiology , Hispanic or Latino , Humans , Middle Aged , Neural Tube Defects/epidemiology , Neural Tube Defects/prevention & control , Nutritional Requirements , Preconception Care/methods , Pregnancy , Prevalence , Racial Groups/genetics , United States , Zea mays
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