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1.
Nutrients ; 16(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38542731

RESUMO

Gestational diabetes (GDM) is associated with a long-term risk of diabetes. We aimed to determine whether a text-messaging-based lifestyle support program would improve diabetes risk factors following GDM. Women with GDM were randomised following delivery to receive four text messages per week supporting a healthy lifestyle and parenting for 6 months, with feedback from an activity monitor (intervention), or to receive the activity monitor only (control). The primary outcome was a composite of weight, physical activity and dietary goals. There were 177 women randomised, with 88 intervention and 89 control participants. All the participants experienced COVID-19 lockdowns during the study. Six-month primary outcome data were obtained for 57 intervention participants and 56 controls. There were 7/57 (12%) intervention and 6/56 (11%) control participants who met the primary outcome (relative risk, 1.08; 95%CI, 0.63-1.85; p = 0.79). Two intervention participants met the dietary goals compared to none of the control participants (p = NS). The intervention participants were more likely to record >1000 steps/day (on 102 ± 59 vs. 81 ± 59 days, p = 0.03). When analysed monthly, this was not initially different but became significant 3-6 months post-partum. Interviews and surveys indicated that with the Intervention, healthier choices were made, but these were negatively impacted by COVID-19 restrictions. Participants found the messages motivational (74%) and the activity monitor useful (71%). In conclusion, no improvement in the diabetes risk factors occurred among the women receiving the text messaging intervention when affected by COVID-19 restrictions.


Assuntos
COVID-19 , Diabetes Gestacional , Envio de Mensagens de Texto , Gravidez , Humanos , Feminino , Diabetes Gestacional/prevenção & controle , Estilo de Vida , Fatores de Risco , COVID-19/prevenção & controle
2.
Nat Commun ; 9(1): 4377, 2018 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-30348949

RESUMO

Rare-earth substituted inorganic phosphors are critical for solid state lighting. New phosphors are traditionally identified through chemical intuition or trial and error synthesis, inhibiting the discovery of potential high-performance materials. Here, we merge a support vector machine regression model to predict a phosphor host crystal structure's Debye temperature, which is a proxy for photoluminescent quantum yield, with high-throughput density functional theory calculations to evaluate the band gap. This platform allows the identification of phosphors that may have otherwise been overlooked. Among the compounds with the highest Debye temperature and largest band gap, NaBaB9O15 shows outstanding potential. Following its synthesis and structural characterization, the structural rigidity is confirmed to stem from a unique corner sharing [B3O7]5- polyanionic backbone. Substituting this material with Eu2+ yields UV excitation bands and a narrow violet emission at 416 nm with a full-width at half-maximum of 34.5 nm. More importantly, NaBaB9O15:Eu2+ possesses a quantum yield of 95% and excellent thermal stability.

3.
Drugs R D ; 18(1): 45-49, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29214385

RESUMO

BACKGROUND: Dimethyl trisulfide (DMTS) is a highly lipid-soluble cyanide (CN) antidote candidate molecule. In prior studies with various US FDA-approved co-solvents, surfactants, and their combinations, aqueous solutions containing 15% polysorbate 80 (Poly80) were found to effectively solubilize DMTS in formulations for intramuscular administration. However, DMTS formulated in 15% aqueous Poly80 solutions showed gradual losses over time when stored in vials with septum-based seals. OBJECTIVE: The present study tested whether storing DMTS formulations in hermetically sealed glass ampules could mitigate storage losses. METHODS: Samples consisted of 1-mL aliquots of a 50 mg/ml stock solution of DMTS in 15% aqueous Poly80. The control samples were stored using a vial-within-a-vial system-the inner and outer vials were sealed respectively, with a snap cap, and with a crimped septum. The hermetically sealed test samples were stored in fire-sealed glass ampules. The DMTS content was measured by HPLC-UV analysis at specific time points over a 100-day period. RESULTS: While the control samples exhibited systematic DMTS losses, no DMTS losses were observed from the test samples stored in hermetically sealed glass ampules over the 100-day testing period. CONCLUSION: DMTS formulated in 15% aqueous Poly80 solution has excellent stability when stored in fire-sealed glass ampules and thus has the potential to be effectively stored as an intramuscular CN countermeasure for mass casualty scenarios.


Assuntos
Antídotos/química , Armazenamento de Medicamentos/métodos , Sulfetos/química , Polissorbatos/química
4.
Inorg Chem ; 57(1): 519-527, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-29260865

RESUMO

Following an investigation proving La2Si4N6C crystallizes in a monoclinic space group, isostructural to Y2Si4N6C, the reportedly hexagonal (La0.5Y0.5)2Si4N6C was reinvestigated to examine the apparent crystal structure change across the solid solution. Initially, calculating the electronic structure and phonon density of states of (La0.5Y0.5)2Si4N6C in the P63mc space group revealed an imaginary phonon mode, which is indicative of a structural instability. Displacing the atoms along the pathway of the imaginary vibration led to a previously unreported space group for carbonitridosilicates, trigonal P31c. The assignment of the trigonal space group was subsequently confirmed by synthesizing (La0.5Y0.5)2Si4N6C using high-temperature, solid state synthesis and analyzing the crystal structure with high-resolution synchrotron X-ray powder diffraction. Preparing the solid solution, (LaδY1-δ)1.98Ce0.02Si4N6C (δ = 0-0.5), showed that the crystal structure changes from the monoclinic to the trigonal space group at δ ≈ 0.25. Finally, substituting Ce3+ in the crystal structure to investigate the optical response via steady-state luminescent and photoluminescent quantum yield measurements reveals severe luminescent quenching with increasing La3+ content, due to a combination of absorption of luminescence by the host structure and thermal quenching. These results display the virtue of combining computational and experimental techniques to solve inorganic crystal structures and assess potential phosphor hosts.

5.
Pharm Dev Technol ; 22(8): 958-963, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26740339

RESUMO

This study focused on the solubility enhancement and the in vivo antidotal efficacy testing of a new potential cyanide (CN) countermeasure, dimethyl trisulfide (DMTS). Various FDA approved cyclodextrins (HPßCD, RMßCD, HPγCD), cosolvents (ethanol, polyethylene glycols, propylene glycol), surfactants (cremophor EL, cremophor RH 40, sodium cholate, sodium deoxycholate, polysorbate 80) and their combinations were applied. Based on the solubility enhancing potential of the tested systems, polysorbate 80 was chosen for further in vivo efficacy studies. A composition comprising 15% polysorbate 80 and 50 mg/ml DMTS with the applied DMTS dose of 100 mg/kg provided a therapeutic antidotal protection of 3.4 × LD50. For comparison, the present therapy of sodium thiosulfate (TS) with the dose of 100 mg/kg provided only 1.1 × LD50 protection, and at the dose of 200 mg/kg, the LD50 was enhanced by 1.3 times. No difference in the therapeutic protection by DMTS was detected when the concentration of polysorbate 80 was increased to 20% (3.2 × LD50 protection). These data demonstrate the potential importance of DMTS as a CN countermeasure, and the formulation comprising polysorbate 80 provides the base of an injectable intramuscular dosage form that can later serve as a CN antidotal kit suitable for mass scenario.


Assuntos
Antídotos/química , Antídotos/farmacologia , Cianetos/intoxicação , Sulfetos/química , Sulfetos/farmacologia , Animais , Masculino , Camundongos
6.
ACS Appl Mater Interfaces ; 8(40): 26956-26963, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27635436

RESUMO

Inorganic persistent luminescent phosphors are an excellent class of optical reporters for enabling sensitive point-of-care diagnostics, particularly with smartphone-based biosensing devices in testing formats such as the lateral flow assay (LFA). Here, the development of persistent phosphors for this application is focused on the solid solution (Sr1-δBaδ)2MgSi2O7:Eu2+,Dy3+ (δ = 0, 0.125, 0.25, 0.375), which is prepared using a high-temperature solid-state reaction as confirmed by synchrotron X-ray powder diffraction. The substitution of barium for strontium enables control over the Eu2+ 5d-orbital crystal field splitting (CFS) as a tool for tuning the emission wavelength while maintaining luminescence lifetimes >9 min across the composition range. Thermoluminescence measurements of the solid solution provide evidence that trap states contribute to the persistent lifetimes with the trap depths also remaining constant as a function of composition. Time-gated luminescence images of these compounds are captured on a smartphone arranged in a layout to mimic a point-of-care test and demonstrate the viability of using these materials as optical reporters. Moreover, comparing the blue-emitting (Sr0.625Ba0.375)2MgSi2O7:Eu2+,Dy3+ and the green-emitting SrAl2O4:Eu2+,Dy3+ in a single LFA-type format shows these two compounds can be detected and resolved simultaneously, thereby permitting the development of a multiplexed LFA.


Assuntos
Luminescência , Cor , Disprósio , Európio , Silicatos de Magnésio , Sistemas Automatizados de Assistência Junto ao Leito , Estrôncio
7.
Curr Drug Deliv ; 13(8): 1351-1357, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26996369

RESUMO

This study represents a new formulation of the novel Cyanide (CN) antidote, Dimethyl trisulfide (DMTS), for intramuscular administration. This is a naturally occurring organosulfur molecule with the capability of reacting with CN more efficiently than the present sulfur donor type CN therapy of Thiosulfate (TS). Two types of micelles (PEG2000-DSPE and PEG2000-DSPE/TPGS) were prepared and tested for their ability to encapsulate the liquid, highly lipophilic and volatile drug, DMTS. The micellar encapsulation for DMTS does not only eliminate the possible muscle necrosis at the injection sites, but the rate of evaporation within the micelles is suppressed, that can provide a level of stability for the formulation. The method of micelle preparation was optimized and it was demonstrated that the PEG2000-DSPE preparation can dissolve up to 2.0 mg/ml of the antidote candidate. Keeping the injection volume minimized this could provide a maximum DMTS dose of 12.5 mg/kg. However, even this low dose of DMTS showed a remarkable in vivo therapeutic efficacy (2 X LD50 protection) in a mice model when injected intramuscularly. These in vitro and in vivo findings proved the efficacy of DMTS in combating CN intoxication, and the presented work gives valuable insight to micelle preparation and sets the bases for a more advanced future formulation of DMTS.


Assuntos
Antídotos/administração & dosagem , Cianetos/antagonistas & inibidores , Portadores de Fármacos/administração & dosagem , Sulfetos/administração & dosagem , Animais , Antídotos/química , Antídotos/uso terapêutico , Cianetos/toxicidade , Portadores de Fármacos/química , Portadores de Fármacos/uso terapêutico , Injeções Intramusculares , Masculino , Camundongos , Micelas , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Fosfatidiletanolaminas/administração & dosagem , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/uso terapêutico , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Polietilenoglicóis/uso terapêutico , Solubilidade , Sulfetos/química , Sulfetos/uso terapêutico , Vitamina E/administração & dosagem , Vitamina E/química , Vitamina E/uso terapêutico
8.
J Anal Methods Chem ; 2016: 6546475, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28053802

RESUMO

These studies represent the first report on the intravascular residence time determinations for the cyanide antidote dimethyl trisulfide (DMTS) in a rat model by using high performance liquid chromatography coupled with ultraviolet absorption spectroscopy (HPLC-UV). The newly developed sample preparation included liquid-liquid extraction by cyclohexanone. The calibration curves showed a linear response for DMTS concentrations between 0.010 and 0.30 mg/mL with R2 = 0.9994. The limit of detection for DMTS via this extraction method was 0.010 mg/mL, and the limit of quantitation was 0.034 mg/mL. Thus this calibration curve provided a tool for determining DMTS in the range between 0.04 and 0.30 mg/mL. Rats were given 20 mg/kg DMTS dose (in 15% Polysorbate 80) intravenously, and blood samples were taken 15, 60, 90, 120, and 240 min after DMTS injections. The data points were plotted as DMTS concentration in RBCs versus time, and the intravascular residence time was determined graphically. The results indicated a half-life of 36 min in a rat model, suggesting that the circulation time is long enough to provide a reasonable time interval for cyanide antagonism.

10.
Diabetes Res Clin Pract ; 108(1): 72-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25661662

RESUMO

AIMS: To assess the concordance between the HbA1c and the oral glucose tolerance test (OGTT) for the diagnosis of diabetes and prediabetes following gestational diabetes (GDM) in an ethnically diverse population. METHODS: Women with GDM underwent a concurrent OGTT and HbA1c test 6-12 weeks postpartum. RESULTS: There were 114 women with GDM who had a 75 g 2-h OGTT and HbA1c at 9.0 ± 3.2 weeks postpartum. Five subjects had diabetes using OGTT criteria, and 4 by HbA1c criteria. No subjects had diabetes on both criteria. The overall concordance between the OGTT and HbA1c for the diagnosis of diabetes, prediabetes, or normal glucose tolerance was only 54% (κ coefficient 0.058, p=0.41). Gravidity, the 2-h glucose level on the OGTT during pregnancy, and the 3rd trimester HbA1c predicted discordance between the postpartum OGTT and HbA1c. CONCLUSIONS: There is poor concordance between the OGTT and HbA1c for the diagnosis of diabetes and prediabetes following GDM. This reflects that the two tests measure different aspects of dysglycemia. In the post-GDM population, the HbA1c misses cases of diabetes as identified by the OGTT. We recommend that the OGTT be retained for postpartum diabetes testing following GDM.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus/sangue , Diabetes Gestacional/sangue , Hemoglobinas Glicadas/metabolismo , Adulto , Diabetes Gestacional/epidemiologia , Feminino , Teste de Tolerância a Glucose , Humanos , Período Pós-Parto , Gravidez , Estudos Retrospectivos
11.
Diabetes Care ; 37(7): 1837-44, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24760259

RESUMO

OBJECTIVE: Vitamin D deficiency in pregnancy is associated with an increased risk of gestational diabetes mellitus (GDM) and neonatal vitamin D deficiency. We conducted a double-blind, randomized controlled trial of low-dose (LD) versus high-dose (HD) vitamin D supplementation to investigate the effects of vitamin D supplementation on glucose metabolism during pregnancy. RESEARCH DESIGN AND METHODS: Women with plasma 25-hydroxyvitamin D (25OHD) levels <32 ng/mL before 20 weeks' gestation were randomized to oral vitamin D3 at 5,000 IU daily (HD) (n = 89) or the recommended pregnancy dose of 400 IU daily (LD) (n = 90) until delivery. The primary end point was maternal glucose levels on oral glucose tolerance test (OGTT) at 26-28 weeks' gestation. Secondary end points included neonatal 25OHD, obstetric and other neonatal outcomes, and maternal homeostasis model assessment of insulin resistance. Analysis was by intention to treat. RESULTS: There was no difference in maternal glucose levels on OGTT. Twelve LD women (13%) developed GDM versus seven (8%) HD women (P = 0.25). Neonatal cord 25OHD was higher in HD offspring (46 ± 11 vs. 29 ± 12 ng/mL, P < 0.001), and deficiency was more common in LD offspring (24 vs. 10%, P = 0.06). Post hoc analysis in LD women showed an inverse relationship between pretreatment 25OHD and both fasting and 2-h blood glucose level on OGTT (both P < 0.001). Baseline 25OHD remained an independent predictor after multiple regression analysis. CONCLUSIONS: HD vitamin D supplementation commencing at a mean of 14 weeks' gestation does not improve glucose levels in pregnancy. However, in women with baseline levels <32 ng/mL, 5,000 IU per day was well tolerated and highly effective at preventing neonatal vitamin D deficiency.


Assuntos
Colecalciferol/uso terapêutico , Diabetes Gestacional/prevenção & controle , Deficiência de Vitamina D/tratamento farmacológico , Vitamina D/análogos & derivados , Adulto , Colecalciferol/administração & dosagem , Colecalciferol/efeitos adversos , Diabetes Gestacional/epidemiologia , Diabetes Gestacional/etiologia , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Método Duplo-Cego , Jejum , Feminino , Glucose/metabolismo , Teste de Tolerância a Glucose , Humanos , Resistência à Insulina , Gravidez , Complicações na Gravidez/tratamento farmacológico , Vitamina D/sangue , Deficiência de Vitamina D/complicações , Adulto Jovem
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