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1.
J Org Chem ; 88(5): 3321-3325, 2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36812364

RESUMEN

Propargyl alcohol derivatives were readily oxidized using Bobbitt's salt to yield the corresponding propynal products. 2-Butyn-1,4-diol may be selectively oxidized to provide either 4-hydroxy-2-butynal or acetylene dicarboxaldehyde, and the resulting stable dichloromethane solutions containing the chemically sensitive acetylene aldehydes were used directly in subsequent Wittig, Grignard, or Diels-Alder reactions. This method provides safe and efficient access to propynals and allows the preparation of polyfunctional acetylene compounds from readily accessible starting material without the use of protecting groups.

2.
Future Oncol ; 19(1): 29-36, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36622264

RESUMEN

Aim: Despite numerous available antiemetics, chemotherapy induced nausea and vomiting (CINV) still affects many patients, and CINV related hospitalizations and costs often result. Materials & methods: PrecisionQ analyzed its database to evaluate CINV related hospitalizations and costs following antiemetics use including netupitant/fosnetupitant with palonosetron (NEPA), aprepitant/fosaprepitant with ondansetron (APON) or aprepitant/fosaprepitant with palonosetron (APPA) in patients receiving highly emetogenic chemotherapy or moderately emetogenic chemotherapy. Results: Database analysis identified 15,583 patient records (807 NEPA, 2023 APON, 12,753 APPA) and mean CINV related hospitalization costs were lower across all patients receiving NEPA (US$301) compared with patients receiving APON ($1006, p < 0.0001) or APPA ($321, p < 0.0001). Conclusion: NEPA is associated with lower CINV related hospitalization costs compared with APON and APPA among patients receiving highly emetogenic chemotherapy or moderately emetogenic chemotherapy.


Chemotherapy patients often experience nausea and vomiting that not only has a negative impact on the patient's quality of life but can also result in unplanned hospitalizations with high associated costs. Numerous medications and specific guidelines are available to prevent nausea and vomiting in patients with cancer. Specifically, the combination of two classes of medications (serotonin inhibitors + neurokinin type 1 inhibitors) has been shown to provide the greatest benefit. However, hospitalizations due to nausea and vomiting still occur, and providers require further information to determine the best options for their patients. In this study, the combination of netupitant/fosnetupitant with palonosetron resulted in lower hospitalization costs compared with aprepitant/fosaprepitant with ondansetron or aprepitant/fosaprepitant with palonosetron in chemotherapy patients.


Asunto(s)
Antieméticos , Antineoplásicos , Humanos , Antieméticos/uso terapéutico , Palonosetrón/uso terapéutico , Aprepitant/efectos adversos , Antineoplásicos/efectos adversos , Náusea/inducido químicamente , Náusea/tratamiento farmacológico , Vómitos/inducido químicamente , Vómitos/tratamiento farmacológico , Quinuclidinas/uso terapéutico
3.
Support Care Cancer ; 31(12): 654, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37878086

RESUMEN

PURPOSE: Chemotherapy-induced nausea and vomiting (CINV)'s impact on work loss remains poorly described. We evaluated associations between the duration of CINV episodes, CINV-related work loss (CINV-WL), and CINV-related activity impairment (CINV-AI) in patients with breast cancer receiving highly emetogenic chemotherapy. METHODS: We analyzed data from a prospective CINV prophylaxis trial of netupitant/palonestron and dexamethasone for patients receiving an anthracycline and cyclophosphamide (AC) for breast cancer (NCT0340371). Over the observed CINV duration (0-5 days), we analyzed patient-reported CINV-WL and CINV-AI for the first two chemotherapy cycles. We categorized patients as having either extended (≥ 3 days) or short (1-2 days) CINV duration and quantified its impact on work using the Work Productivity and Activity Impairment Questionnaire (WPAI). RESULTS: Overall, we captured data for 792 cycles in 402 women, including 136 (33.8%) employed patients with 35.3% reporting CINV. Of those with CINV, patients reported CINV-WL in 26 cycles and CINV-AI in 142 cycles. Of those with CINV, 55.3% of extended CINV cycles experienced CINV-WL compared to 16.7% of short CINV cycles (p < 0.001). The relative risk of CINV-WL between extended and short CINV was 3.32 (p < 0.01) for employed patients. The mean difference in CINV-AI scores (higher = worse) between extended and short duration CINV was 5.0 vs. 3.0 (p < 0.001). CONCLUSION: Extended (≥ 3 days) CINV was associated with more than triple the risk of CINV-WL and higher CINV-AI compared with short CINV.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Estudios Prospectivos , Vómitos/inducido químicamente , Vómitos/prevención & control , Náusea/inducido químicamente , Náusea/prevención & control , Antraciclinas
4.
Oncologist ; 26(4): 325-331, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33289268

RESUMEN

PURPOSE: Chemotherapy-induced nausea and vomiting (CINV) contributes to avoidable acute care, a metric now tracked in Medicare's oncology outcome measure. CINV is preventable, yet guidelines are often not followed. We sought to quantify acute care involving CINV and other avoidable toxicities after highly emetogenic chemotherapy (HEC) to identify excess risk and assess clinician adherence to antiemesis guidelines for HEC. MATERIALS AND METHODS: We retrospectively evaluated U.S. electronic health records (2012-2018) using Medicare's OP-35 outcome measure to identify avoidable acute care involving any of 10 toxicities, including CINV, after HEC regimens relative to non-HEC. Antiemetic guideline adherence was defined as use ofneurokinin-1 (NKl) receptor antagonists Q5 (RAs) plus 5-hydroxytryptamine type 3 RA+ dexamethasone at HEC initiation. RESULTS: Among 17,609 patients receiving HEC, acute care rates associated with HEC chemotherapy included 32% cisplatin, 31% carboplatin, and 21% anthracycline/cyclosphospharnide (AC), with 76% meeting the criteria as avoidable events. Oxaliplatin rates were 29%. Avoidable acute care occurred 1.83 times (95% confidence interval, 1.76-1.91, p < .0001) as often after HEC versus non-HEC excluding oxaliplatin; CINV-related acute care occurred 2.29 times as often. Nonadherence to antiemesis guidelines occurred in 34% and 24% of cisplatin and AC courses, respectively, because of omission of a NKl RA. CONCLUSIONS: Patients treated with HEC regimens experienced high avoidable acute care use, 1.8 times the risk seen for other chemotherapy. Nonadherence to guideline-directed antiemetic prophylaxis highlights the need to ensure adherence to antiemetic guidelines, including the use of NKl RA in HEC. IMPLICATIONS FOR PRACTICE: After survival, perhaps the most important goal in oncology is limiting avoidable acute care, a goal now used by Medicare to impact cancer reimbursement. This study found that patients treated with highly emetogenic chemotherapy (HEC) regimens had high rates of avoidable acute care use, 1.8 times the risk seen for other chemotherapy. A substantial proportion of the avoidable acute care involved chemotherapy-induced nausea and vomiting. Results showed that incomplete adherence to national antiemetic guidelines for HEC regimens primarily driven by omission of upfront neurokinin-1 receptor antagonist use, suggesting that improved adherence can meaningfully resolve this gap in quality and cost of care.


Asunto(s)
Antieméticos , Antineoplásicos , Neoplasias , Anciano , Antieméticos/uso terapéutico , Antineoplásicos/efectos adversos , Humanos , Medicare , Náusea/inducido químicamente , Náusea/tratamiento farmacológico , Náusea/prevención & control , Neoplasias/tratamiento farmacológico , Oxaliplatino/uso terapéutico , Estudios Retrospectivos , Estados Unidos , Vómitos/inducido químicamente , Vómitos/tratamiento farmacológico , Vómitos/prevención & control
5.
J Neuroinflammation ; 18(1): 113, 2021 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-33985529

RESUMEN

BACKGROUND: Sex and age are emerging as influential variables that affect spinal cord injury (SCI) recovery. Despite a changing demographic towards older age at the time of SCI, the effects of sex or age on inflammation remain to be elucidated. This study determined the sex- and age-dependency of the innate immune response acutely after SCI. METHODS: Male and female mice of ages 4- and 14-month-old received T9 contusion SCI and the proportion of microglia, monocyte-derived macrophages (MDM), and neutrophils surrounding the lesion were determined at 3- and 7-day post-injury (DPI) using flow cytometry. Cell counts of microglia and MDMs were obtained using immunohistochemistry to verify flow cytometry results at 3-DPI. Microglia and MDMs were separately isolated using fluorescence-activated cell sorting (FACS) at 3-day post-injury (DPI) to assess RNA expression of 27 genes associated with activation, redox, and debris metabolism/clearance. RESULTS: Flow cytometry revealed that being female and older at the time of injury significantly increased MDMs relative to other phagocytes, specifically increasing the ratio of MDMs to microglia at 3-DPI. Cell counts using immunohistochemistry revealed that male mice have more total microglia within SCI lesions that can account for a lower MDM/microglia ratio. With NanoString analyses of 27 genes, only 1 was differentially expressed between sexes in MDMs; specifically, complement protein C1qa was increased in males. No genes were affected by age in MDMs. Only 2 genes were differentially regulated in microglia between sexes after controlling for false discovery rate, specifically CYBB (NOX2) as a reactive oxygen species (ROS)-associated marker as well as MRC1 (CD206), a gene associated with reparative phenotypes. Both genes were increased in female microglia. No microglial genes were differentially regulated between ages. Differences between microglia and MDMs were found in 26 of 27 genes analyzed, all expressed higher in MDMs with three exceptions. Specifically, C1qa, cPLA2, and CD86 were expressed higher in microglia. CONCLUSIONS: These findings indicate that inflammatory responses to SCI are sex-dependent at both the level of cellular recruitment and gene expression.


Asunto(s)
Reacción de Fase Aguda/metabolismo , Envejecimiento , Macrófagos/metabolismo , Microglía/metabolismo , Caracteres Sexuales , Traumatismos de la Médula Espinal/metabolismo , Factores de Edad , Animales , Modelos Animales de Enfermedad , Femenino , Expresión Génica , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Factores Sexuales
6.
J Biol Chem ; 294(39): 14370-14382, 2019 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-31395659

RESUMEN

A critical step in the development of chronic inflammatory diseases is the accumulation of proinflammatory macrophages in the extracellular matrix (ECM) of peripheral tissues. The adhesion receptor integrin αDß2 promotes the development of atherosclerosis and diabetes by supporting macrophage retention in inflamed tissue. We recently found that the end product of docosahexaenoic acid (DHA) oxidation, 2-(ω-carboxyethyl)pyrrole (CEP), serves as a ligand for αDß2 CEP adduct with ECM is generated during inflammation-mediated lipid peroxidation. The goal of this project was to identify a specific inhibitor for αDß2-CEP interaction that can prevent macrophage accumulation. Using a specially designed peptide library, Biacore-detected protein-protein interaction, and adhesion of integrin-transfected HEK 293 cells, we identified a sequence (called P5 peptide) that significantly and specifically inhibited αD-CEP binding. In the model of thioglycollate-induced peritoneal inflammation, the injection of cyclic P5 peptide reduced 3-fold the macrophage accumulation in WT mice but had no effect in αD-deficient mice. The tracking of adoptively transferred, fluorescently labeled WT and αD-/- monocytes in the model of peritoneal inflammation and in vitro two-dimensional and three-dimensional migration assays demonstrated that P5 peptide does not affect monocyte transendothelial migration or macrophage efflux from the peritoneal cavity but regulates macrophage migration through the ECM. Moreover, the injection of P5 peptide into WT mice on a high-fat diet prevents macrophage accumulation in adipose tissue in an αDß2-dependent manner. Taken together, these results demonstrate the importance of αDß2-mediated macrophage adhesion for the accumulation of infiltrating macrophages in the inflamed ECM and propose P5 peptide as a potential inhibitor of atherogenesis and diabetes.


Asunto(s)
Antiinflamatorios/farmacología , Movimiento Celular , Macrófagos Peritoneales/metabolismo , Péptidos Cíclicos/farmacología , Peritonitis/tratamiento farmacológico , Pirroles/metabolismo , Animales , Antiinflamatorios/uso terapéutico , Células Cultivadas , Células HEK293 , Humanos , Cadenas alfa de Integrinas/metabolismo , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/fisiología , Ratones , Ratones Endogámicos C57BL , Péptidos Cíclicos/uso terapéutico , Peritonitis/etiología , Unión Proteica , Tioglicolatos/toxicidad
7.
Planta ; 252(4): 64, 2020 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-32968874

RESUMEN

MAIN CONCLUSION: Transcriptomic analysis revealed maleic hydrazide suppresses apical and axillary bud development by altering the expression of genes related to meristem development, cell division, DNA replication, DNA damage and recombination, and phytohormone signaling. Topping (removal of apical buds) is a common agricultural practice for some crop plants including cotton, cannabis, and tobacco. Maleic hydrazide (MH) is a systemic suckercide, a chemical that inhibits shoot bud growth, used to control the growth of apical (ApB) and axillary buds (AxB) following topping. However, the influence of MH on gene expression and the underlying molecular mechanism of controlling meristem development are not well studied. Our RNA sequencing analysis showed that MH significantly influences the transcriptomic landscape in ApB and AxB of chemically topped tobacco. Gene ontology (GO) enrichment analysis revealed that upregulated genes in ApB were enriched for phosphorelay signal transduction, and the regulation of transition timing from vegetative to reproductive phase, whereas downregulated genes were largely associated with meristem maintenance, cytokinin metabolism, cell wall synthesis, photosynthesis, and DNA metabolism. In MH-treated AxB, GO terms related to defense response and oxylipin metabolism were overrepresented in upregulated genes. GO terms associated with cell cycle, DNA metabolism, and cytokinin metabolism were enriched in downregulated genes. Expression of KNOX and MADS transcription factor (TF) family genes, known to be involved in meristem development, were affected in ApB and AxB by MH treatment. The promoters of MH-responsive genes are enriched for several known cis-acting elements, suggesting the involvement of a subset of TF families. Our findings suggest that MH affects shoot bud development in chemically topped tobacco by altering the expression of genes related to meristem development, DNA repair and recombination, cell division, and phytohormone signaling.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Hidrazida Maleica , Nicotiana , Brotes de la Planta , Transcriptoma , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Hidrazida Maleica/farmacología , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/genética , Nicotiana/efectos de los fármacos , Nicotiana/genética , Transcriptoma/efectos de los fármacos
8.
Phys Rev Lett ; 124(11): 117202, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-32242705

RESUMEN

We experimentally identify coherent spin pumping in the magnon-magnon hybrid modes of yttrium iron garnet/permalloy (YIG/Py) bilayers. By reducing the YIG and Py thicknesses, the strong interfacial exchange coupling leads to large avoided crossings between the uniform mode of Py and the spin wave modes of YIG enabling accurate determination of modification of the linewidths due to the dampinglike torque. We identify additional linewidth suppression and enhancement for the in-phase and out-of-phase hybrid modes, respectively, which can be interpreted as concerted dampinglike torque from spin pumping. Furthermore, varying the Py thickness shows that both the fieldlike and dampinglike couplings vary like 1/sqrt[t_{Py}], verifying the prediction by the coupled Landau-Lifshitz equations.

9.
N Engl J Med ; 375(17): 1617-1627, 2016 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-27783918

RESUMEN

BACKGROUND: Long-term treatment with supplemental oxygen has unknown efficacy in patients with stable chronic obstructive pulmonary disease (COPD) and resting or exercise-induced moderate desaturation. METHODS: We originally designed the trial to test whether long-term treatment with supplemental oxygen would result in a longer time to death than no use of supplemental oxygen among patients who had stable COPD with moderate resting desaturation (oxyhemoglobin saturation as measured by pulse oximetry [Spo2], 89 to 93%). After 7 months and the randomization of 34 patients, the trial was redesigned to also include patients who had stable COPD with moderate exercise-induced desaturation (during the 6-minute walk test, Spo2 ≥80% for ≥5 minutes and <90% for ≥10 seconds) and to incorporate the time to the first hospitalization for any cause into the new composite primary outcome. Patients were randomly assigned, in a 1:1 ratio, to receive long-term supplemental oxygen (supplemental-oxygen group) or no long-term supplemental oxygen (no-supplemental-oxygen group). In the supplemental-oxygen group, patients with resting desaturation were prescribed 24-hour oxygen, and those with desaturation only during exercise were prescribed oxygen during exercise and sleep. The trial-group assignment was not masked. RESULTS: A total of 738 patients at 42 centers were followed for 1 to 6 years. In a time-to-event analysis, we found no significant difference between the supplemental-oxygen group and the no-supplemental-oxygen group in the time to death or first hospitalization (hazard ratio, 0.94; 95% confidence interval [CI], 0.79 to 1.12; P=0.52), nor in the rates of all hospitalizations (rate ratio, 1.01; 95% CI, 0.91 to 1.13), COPD exacerbations (rate ratio, 1.08; 95% CI, 0.98 to 1.19), and COPD-related hospitalizations (rate ratio, 0.99; 95% CI, 0.83 to 1.17). We found no consistent between-group differences in measures of quality of life, lung function, and the distance walked in 6 minutes. CONCLUSIONS: In patients with stable COPD and resting or exercise-induced moderate desaturation, the prescription of long-term supplemental oxygen did not result in a longer time to death or first hospitalization than no long-term supplemental oxygen, nor did it provide sustained benefit with regard to any of the other measured outcomes. (Funded by the National Heart, Lung, and Blood Institute and the Centers for Medicare and Medicaid Services; LOTT ClinicalTrials.gov number, NCT00692198 .).


Asunto(s)
Terapia por Inhalación de Oxígeno , Oxígeno/sangre , Enfermedad Pulmonar Obstructiva Crónica/terapia , Anciano , Ejercicio Físico/fisiología , Tolerancia al Ejercicio , Femenino , Estudios de Seguimiento , Hospitalización , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Terapia por Inhalación de Oxígeno/efectos adversos , Cooperación del Paciente , Enfermedad Pulmonar Obstructiva Crónica/sangre , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Calidad de Vida , Factores de Tiempo , Insuficiencia del Tratamiento
10.
Brain Behav Immun ; 76: 139-150, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30453022

RESUMEN

OBJECTIVE: The average age at the time of spinal cord injury (SCI) has increased to 43 years old. Middle-aged mice (14 months old, MO) exhibit impaired recovery after SCI with age-dependent increases in reactive oxygen species (ROS) production through NADPH oxidase (NOX) along with pro-inflammatory macrophage activation. Despite these aging differences, clinical therapies are being examined in individuals regardless of age based upon preclinical data generated primarily using young animals (∼4 MO). Our objective is to test the extent to which age affects SCI treatment efficacy. Specifically, we hypothesize that the effectiveness of apocynin, a NOX inhibitor, is age-dependent in SCI. METHODS: Apocynin treatment (5 mg/kg) or vehicle was administered 1 and 6 h after moderate T9 contusion SCI (50kdyn IH) and then daily for 1 week to 4 and 14 MO mice. Locomotor and anatomical recovery was evaluated for 28 days. Monocyte-derived macrophage (MDM) and microglial activation and ROS production were evaluated at 3 and 28 days post-injury. RESULTS: Apocynin improved functional and anatomical recovery in 14 but not 4 MO SCI mice. Apocynin-mediated recovery was coincident with significant reductions in MDM infiltration and MDM-ROS production in 14 MO SCI mice. Importantly, microglial activation was unaffected by treatment. CONCLUSION: These results indicate that apocynin exhibits age-dependent neuroprotective effects by blocking excessive neuroinflammation through NOX-mediated ROS production in MDMs. Further, these data identify age as a critical regulator for SCI treatment efficacy and indicate that pharmacologically reduced macrophage, but not microglia, activation and ROS production reverses age-associated neurological impairments.


Asunto(s)
Activación de Macrófagos/fisiología , NADPH Oxidasas/metabolismo , Traumatismos de la Médula Espinal/fisiopatología , Acetofenonas/farmacología , Factores de Edad , Animales , Modelos Animales de Enfermedad , Femenino , Inflamación , Macrófagos/fisiología , Ratones , Ratones Endogámicos C57BL , Microglía/metabolismo , NADPH Oxidasas/fisiología , Fármacos Neuroprotectores , Oxidación-Reducción , Estrés Oxidativo/fisiología , Especies Reactivas de Oxígeno/metabolismo , Traumatismos de la Médula Espinal/inmunología
11.
J Org Chem ; 84(9): 5783-5789, 2019 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-30933498

RESUMEN

In order to elucidate to what extent Coulombic and other interactions contribute to the origins of contrasteric phenomena, we have identified a significant, previously unrecognized interaction between fluorine-containing motifs and groups or molecules containing main-group heteroatoms. The axial conformers of both 2-methoxy- and 2-trifluoromethoxytetrahydropyrans preferentially adopt a rotameric arrangement in which the OCH3 and the OCF3 groups are gauche to the ring oxygen. Given that one would expect a repulsive Columbic interaction to exist between the electronegative fluorines of the CF3 group and the ring oxygen in this rotomeric orientation, this surprising result suggests that an attractive interaction exists between the CF3 group and the oxygen of the ring. The generality and origin of this interaction was examined using nonpolar CF4 to probe intermolecular interactions with systems such as dimethyl ether, trimethylamine, trimethylphosphine, and acetone. In each case there was an attractive interaction leading to formation of a complex. The attraction is not due to van der Waals forces. Rather, the fluorine lone pairs of the CF4 often act as an electron donor in these complexes leading to a transfer of charge between the reactants and formation of the complex. These previously unrecognized fluorine-heteroatom interactions likely play a significant role in the context of understanding the binding interactions of medicinally relevant molecules or pharmaceuticals possessing fluorine-containing pharmacophores with their targets.

12.
Thorax ; 73(5): 414-421, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29326298

RESUMEN

BACKGROUND: Cigarette smoking is the strongest risk factor for COPD. Smoking burden is frequently measured in pack-years, but the relative contribution of cigarettes smoked per day versus duration towards the development of structural lung disease, airflow obstruction and functional outcomes is not known. METHODS: We analysed cross-sectional data from a large multicentre cohort (COPDGene) of current and former smokers. Primary outcome was airflow obstruction (FEV1/FVC); secondary outcomes included five additional measures of disease: FEV1, CT emphysema, CT gas trapping, functional capacity (6 min walk distance, 6MWD) and respiratory morbidity (St George's Respiratory Questionnaire, SGRQ). Generalised linear models were estimated to compare the relative contribution of each smoking variable with the outcomes, after adjustment for age, race, sex, body mass index, CT scanner, centre, age of smoking onset and current smoking status. We also estimated adjusted means of each outcome by categories of pack-years and combined groups of categorised smoking duration and cigarettes/day, and estimated linear trends of adjusted means for each outcome by categorised cigarettes/day, smoking duration and pack-years. RESULTS: 10 187 subjects were included. For FEV1/FVC, standardised beta coefficient for smoking duration was greater than for cigarettes/day and pack-years (P<0.001). After categorisation, there was a linear increase in adjusted means FEV1/FVC with increase in pack-years (regression coefficient ß=-0.023±SE0.003; P=0.003) and duration over all ranges of smoking cigarettes/day (ß=-0.041±0.004; P<0.001) but a relatively flat slope for cigarettes/day across all ranges of smoking duration (ß=-0.009±0.0.009; P=0.34). Strength of association of duration was similarly greater than pack-years for emphysema, gas trapping, FEV1, 6MWD and SGRQ. CONCLUSION: Smoking duration alone provides stronger risk estimates of COPD than the composite index of pack-years. TRIAL REGISTRATION NUMBER: Post-results; NCT00608764.


Asunto(s)
Fumar Cigarrillos/efectos adversos , Enfermedad Pulmonar Obstructiva Crónica/etiología , Enfisema Pulmonar/diagnóstico por imagen , Anciano , Estudios de Cohortes , Estudios Transversales , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfisema Pulmonar/epidemiología , Enfisema Pulmonar/etiología , Medición de Riesgo/métodos , Encuestas y Cuestionarios , Factores de Tiempo , Tomografía Computarizada por Rayos X , Capacidad Vital , Prueba de Paso
13.
J Org Chem ; 83(9): 5242-5255, 2018 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-29620891

RESUMEN

The origin of the anomeric effect has been reexamined in a coordinated experimental and computational investigation. The results of these studies implicate a number of different, but correlated, interactions that in the aggregate are responsible for the anomeric effect. No single factor is uniquely responsible for the axial preference of a substituent that is the hallmark of the anomeric effect. A CH···G nonbonded attraction between a polar axial substituent (G) and the syn-axial hydrogen(s) in the heterocycle has been demonstrated experimentally. The hyperconjugation model involving electron transfer from a ring heteroatom to an excited state of an axial C-G bond was shown to be, at most, a minor contributor because of the very small changes in charge density at the ring heteroatom(s): the main charge transfer is from hydrogen to G in the H-C-G unit. This appears to result from lengthening the C-G bond to minimize repulsion with the ring atom lone pair(s) and the advantage of having a more positive hydrogen that leads to a stabilizing Coulombic interaction with the ring heteroatom(s). In short, the anomeric effect arises mainly from two separate CH···G nonbonded Coulombic attractions.

14.
Nicotine Tob Res ; 20(2): 224-230, 2018 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-28199715

RESUMEN

Background: Expectancies demonstrate cross-sectional associations with e-cigarette use, but the prospective relationships between expectancies and e-cigarette use are unknown. This study examined the longitudinal associations of expectancies with e-cigarette use among hospitalized tobacco cigarette smokers. Methods: E-cigarette expectancies (e-cigarette-specific Brief Smoking Consequences Questionnaire-Adult [BSCQ-A]), tobacco cigarette expectancies (tobacco-specific BSCQ-A), and number of days used e-cigarettes in the past 30 days were assessed at baseline hospitalization, 6-months post-hospitalization, and 12-months post-hospitalization among 978 hospitalized tobacco cigarette smokers. Expectancy difference scores (e-cigarette-specific expectancies minus tobacco-specific expectancies) were computed for each of the 10 BSCQ-A scales. Cross-lagged panel models tested the relationships between expectancy difference scores and number of days used e-cigarettes in the past 30 days for each of the 10 BSCQ-A scales. Results: Though some models revealed partial associations between expectancies and e-cigarette use, only one yielded results consistent with hypotheses. Greater e-cigarette use at baseline predicted greater expectancies that e-cigarettes taste pleasant as compared to tobacco cigarettes at 6 months, which then predicted greater e-cigarette use at 12 months. To a lesser degree greater expectancies that e-cigarettes taste pleasant as compared to tobacco cigarettes at baseline predicted greater e-cigarette use at 6 months, which then predicted greater expectancies that e-cigarettes taste pleasant as compared to tobacco cigarettes at 12 months. Conclusions: Expectancies that e-cigarettes provide similar or more pleasant taste sensations as compared to tobacco cigarettes may be both a cause and consequence of e-cigarette use. Focusing on the taste experience may prove most effective in modifying e-cigarette use behavior. Implications: The current study offers the first longitudinal examination of expectancies and e-cigarette use. Results suggest expectancies that e-cigarettes provide similar or more pleasant taste sensations relative to tobacco cigarettes are both a cause and consequence of e-cigarette use. Efforts that focus on the e-cigarette taste experience may prove most effective in modifying e-cigarette use behavior.


Asunto(s)
Pacientes Internos/psicología , Fumadores/psicología , Fumar/psicología , Vapeo/psicología , Adulto , Anciano , Actitud Frente a la Salud , Estudios Transversales , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Encuestas y Cuestionarios , Productos de Tabaco , Adulto Joven
15.
Phys Chem Chem Phys ; 20(34): 22210-22217, 2018 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-30118134

RESUMEN

The rotational spectra of 2- and 3-nitrobenzonitrile were recorded via chirped-pulse Fourier transform microwave spectroscopy in the frequency range of 2-8 GHz. These molecules each display large dipole moments, making them viable candidates for deceleration and trapping experiments with AC-electric fields. For both molecules, the main isotopologues and all isotopologues of the respective 13C-, 15N-, 18O-monosubstituted species in their natural abundance were assigned. These assignments allowed for the structural determination of 2- and 3-nitrobenzonitrile via Kraitchman's equations as well as a mass-dependent least-squares fitting approach. The experimentally determined structural parameters are then compared to those obtained from quantum-chemical calculations for these two molecules and 4-nitrobenzonitrile. Structural changes caused by steric interaction and competition for the electron density of the phenyl ring highlight how these strong electron-withdrawing substituents affect one another according to their respective positions on the phenyl ring.

16.
Biomed Eng Online ; 17(1): 72, 2018 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-29866122

RESUMEN

BACKGROUND: Air ions are molecules of air that have become ionized-that is, they have either lost or gained an electrical charge. Past speculation has suggested that exposure to positive air ions may be harmful to one's health, while exposure to negative air ions may be associated with beneficial health effects. Air ions arise from natural sources as well as direct-current transmission lines and commercial ionizers. Several recent clinical studies have suggested therapeutic effects of air ions on various types of depression at exposure levels 10- to 1000-fold higher than most previous human studies. The aim of this study was to assess the evidence from studies of laboratory animals for beneficial or adverse effects of air ions on health. METHODS: Sixty-two studies (1935-2015) in nine topics areas were evaluated for quality and potential systematic bias by ARRIVE guidelines. Standardized mean differences or proportional differences between exposed and control groups were computed for 44 studies to quantitatively assess the strength of the evidence for exposure-related effects. RESULTS: Many of the studies were conducted before 1990 and exhibited various reporting and methodological deficiencies, including small sample size, failure to control for the influence of potential confounding variables, lack of randomized assignment to treatment groups and blinded analyses, and statistical errors relating to treating group-exposed animals as individuals. The highest quality studies consistently reported no effects of exposure on any of the endpoints examined. There were no evident dose-response relationships within or across studies. CONCLUSIONS: Experimental studies of laboratory animals exposed to positive and negative air ions for minutes to years over a five-log unit range of intensities did not suggest any consistent or reliable effects on measures of behavior, learning and memory, neurotransmitters, tracheal function, respiratory infection, cardiovascular function, reproduction and growth, carcinogenesis, or other health endpoints. These data do not provide evidence of adverse or beneficial effects of air ion exposure on health, and did not suggest any biological mechanism of interaction, except perhaps for mechanosensory stimulation of body surfaces by static electric fields at high air ion concentrations.


Asunto(s)
Aire , Animales de Laboratorio , Conducta Animal/efectos de los fármacos , Fenómenos Fisiológicos/efectos de los fármacos , Animales
17.
Environ Res ; 160: 60-76, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28963966

RESUMEN

BACKGROUND: The construction of high-voltage direct current (HVDC) lines for the long-distance transport of energy is becoming increasingly popular. This has raised public concern about potential environmental impacts of the static electric fields (EF) produced under and near HVDC power lines. As the second part of a comprehensive literature analysis, the aim of this systematic review was to assess the effects of static EF exposure on biological functions in invertebrates and plants and to provide the basis for an environmental impact assessment of such exposures. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was used to guide the methodological conduct and reporting. RESULTS: Thirty-three studies - 14 invertebrate and 19 plant studies - met the eligibility criteria and were included in this review. The reported behavioral responses of insects and planarians upon exposure strongly suggest that invertebrates are able to perceive the presence of a static EF. Many other studies reported effects on physiological functions that were expressed as, for example, altered metabolic activity or delayed reproductive and developmental stages in invertebrates. In plants, leaf damage, alterations in germination rates, growth and yield, or variations in the concentration of essential elements, for example, have been reported. However, these physiological responses and changes in plant morphology appear to be secondary to surface stimulation by the static EF or caused by concomitant parameters of the electrostatic environment. Furthermore, all of the included studies suffered from methodological flaws, which lowered credibility in the results. CONCLUSION: At field levels encountered from natural sources or HVDC lines (< 35kV/m), the available data provide reliable evidence that static EF can trigger behavioral responses in invertebrates, but they do not provide evidence for adverse effects of static EF on other biological functions in invertebrates and plants. At far higher field levels (> 35kV/m), adverse effects on physiology and morphology, presumably caused by corona-action, appear to be more likely. Higher quality studies are needed to unravel the role of air ions, ozone, nitric oxide and corona current on alterations in physiological functions and morphology.


Asunto(s)
Invertebrados/efectos de la radiación , Plantas/efectos de la radiación , Electricidad Estática/efectos adversos , Animales
18.
N Engl J Med ; 370(23): 2201-10, 2014 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-24836125

RESUMEN

BACKGROUND: Retrospective studies have shown that statins decrease the rate and severity of exacerbations, the rate of hospitalization, and mortality in chronic obstructive pulmonary disease (COPD). We prospectively studied the efficacy of simvastatin in preventing exacerbations in a large, multicenter, randomized trial. METHODS: We designed the Prospective Randomized Placebo-Controlled Trial of Simvastatin in the Prevention of COPD Exacerbations (STATCOPE) as a randomized, controlled trial of simvastatin (at a daily dose of 40 mg) versus placebo, with annual exacerbation rates as the primary outcome. Patients were eligible if they were 40 to 80 years of age, had COPD (defined by a forced expiratory volume in 1 second [FEV1] of less than 80% and a ratio of FEV1 to forced vital capacity of less than 70%), and had a smoking history of 10 or more pack-years, were receiving supplemental oxygen or treatment with glucocorticoids or antibiotic agents, or had had an emergency department visit or hospitalization for COPD within the past year. Patients with diabetes or cardiovascular disease and those who were taking statins or who required statins on the basis of Adult Treatment Panel III criteria were excluded. Participants were treated from 12 to 36 months at 45 centers. RESULTS: A total of 885 participants with COPD were enrolled for approximately 641 days; 44% of the patients were women. The patients had a mean (±SD) age of 62.2±8.4 years, an FEV1 that was 41.6±17.7% of the predicted value, and a smoking history of 50.6±27.4 pack-years. At the time of study closeout, the low-density lipoprotein cholesterol levels were lower in the simvastatin-treated patients than in those who received placebo. The mean number of exacerbations per person-year was similar in the simvastatin and placebo groups: 1.36±1.61 exacerbations and 1.39±1.73 exacerbations, respectively (P=0.54). The median number of days to the first exacerbation was also similar: 223 days (95% confidence interval [CI], 195 to 275) and 231 days (95% CI, 193 to 303), respectively (P=0.34). The number of nonfatal serious adverse events per person-year was similar, as well: 0.63 events with simvastatin and 0.62 events with placebo. There were 30 deaths in the placebo group and 28 in the simvastatin group (P=0.89). CONCLUSIONS: Simvastatin at a daily dose of 40 mg did not affect exacerbation rates or the time to a first exacerbation in patients with COPD who were at high risk for exacerbations. (Funded by the National Heart, Lung, and Blood Institute and the Canadian Institutes of Health Research; STATCOPE ClinicalTrials.gov number, NCT01061671.).


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Simvastatina/uso terapéutico , Adulto , Anciano , Femenino , Volumen Espiratorio Forzado , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Lípidos/sangre , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Calidad de Vida , Índice de Severidad de la Enfermedad , Simvastatina/efectos adversos , Insuficiencia del Tratamiento , Capacidad Vital
19.
Respir Res ; 18(1): 124, 2017 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-28629419

RESUMEN

BACKGROUND: Beta-blockers are commonly prescribed for patients with cardiovascular disease. Providers have been wary of treating chronic obstructive pulmonary disease (COPD) patients with beta-blockers due to concern for bronchospasm, but retrospective studies have shown that cardio-selective beta-blockers are safe in COPD and possibly beneficial. However, these benefits may reflect symptom improvements due to the cardiac effects of the medication. The purpose of this study is to evaluate associations between beta-blocker use and both exacerbation rates and longitudinal measures of lung function in two well-characterized COPD cohorts. METHODS: We retrospectively analyzed 1219 participants with over 180 days of follow up from the STATCOPE trial, which excluded most cardiac comorbidities, and from the placebo arm of the MACRO trial. Primary endpoints were exacerbation rates per person-year and change in spirometry over time in association with beta blocker use. RESULTS: Overall 13.9% (170/1219) of participants reported taking beta-blockers at enrollment. We found no statistically significant differences in exacerbation rates with respect to beta-blocker use regardless of the prevalence of cardiac comorbidities. In the MACRO cohort, patients taking beta-blockers had an exacerbation rate of 1.72/person-year versus a rate of 1.71/person-year in patients not taking beta-blockers. In the STATCOPE cohort, patients taking beta-blockers had an exacerbation rate of 1.14/person-year. Patients without beta-blockers had an exacerbation rate of 1.34/person-year. We found no detrimental effect of beta blockers with respect to change in lung function over time. CONCLUSION: We found no evidence that beta-blocker use was unsafe or associated with worse pulmonary outcomes in study participants with moderate to severe COPD.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Pulmón/efectos de los fármacos , Pulmón/fisiología , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Antagonistas Adrenérgicos beta/farmacología , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Pruebas de Función Respiratoria/métodos , Estudios Retrospectivos , Resultado del Tratamiento
20.
J Gen Intern Med ; 32(12): 1315-1322, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28884423

RESUMEN

BACKGROUND: Electronic cigarettes (e-cigarettes) are battery-operated nicotine-delivery devices used by some smokers as a cessation tool as well as by never smokers. OBJECTIVE: To determine the usage of e-cigarettes in older adults at risk for or with chronic obstructive pulmonary disease (COPD). DESIGN: Prospective cohorts. PARTICIPANTS: COPDGene (N = 3536) and SPIROMICS (N = 1060) subjects who were current or former smokers aged 45-80. MAIN MEASURES: Participants were surveyed to determine whether e-cigarette use was associated with longitudinal changes in COPD progression or smoking habits. KEY RESULTS: From 2010 to 2016, participants who had ever used e-cigarettes steadily increased to 12-16%, but from 2014 to 2016 current use was stable at ~5%. E-cigarette use in African-Americans (AA) and whites was similar; however, AA were 1.8-2.9 times as likely to use menthol-flavored e-cigarettes. Current e-cigarette and conventional cigarette users had higher nicotine dependence and consumed more nicotine than those who smoked only conventional cigarettes. E-cigarette users had a heavier conventional cigarette smoking history and worse respiratory health, were less likely to reduce or quit conventional cigarette smoking, had higher nicotine dependence, and were more likely to report chronic bronchitis and exacerbations. Ever e-cigarette users had more rapid decline in lung function, but this trend did not persist after adjustment for persistent conventional cigarette smoking. CONCLUSIONS: E-cigarette use, which is common in adults with or at risk for COPD, was associated with worse pulmonary-related health outcomes, but not with cessation of smoking conventional cigarettes. Although this was an observational study, we find no evidence supporting the use of e-cigarettes as a harm reduction strategy among current smokers with or at risk for COPD.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Vapeo/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Bronquitis/epidemiología , Bronquitis/etiología , Fumar Cigarrillos/epidemiología , Estudios de Cohortes , Progresión de la Enfermedad , Sistemas Electrónicos de Liberación de Nicotina/estadística & datos numéricos , Femenino , Reducción del Daño , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Prevalencia , Enfermedad Pulmonar Obstructiva Crónica/etiología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Índice de Severidad de la Enfermedad , Cese del Hábito de Fumar/métodos , Cese del Hábito de Fumar/estadística & datos numéricos , Tabaquismo/epidemiología , Estados Unidos/epidemiología , Vapeo/efectos adversos
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