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2.
PLoS One ; 18(5): e0285582, 2023.
Article in English | MEDLINE | ID: mdl-37200349

ABSTRACT

OBJECTIVES: To determine the association between enrollment in Medicaid prior to release compared with post-release, and the use of health services and time to the first service use after release among Louisiana Medicaid members within one year of release from Louisiana state corrections custody. METHODS: We conducted a retrospective cohort study linking Louisiana Medicaid and Louisiana state corrections release data. We included individuals ages 19 to 64 years released from state custody between January 1, 2017 and June 30, 2019 and enrolled in Medicaid within 180 days of release. Outcome measures included receipt of general health services (primary care visits, emergency department visits, and hospitalizations), cancer screenings, specialty behavioral health services, and prescription medications. To determine the association between pre-release Medicaid enrollment and time to receipt of health services, multivariable regression models were used which accounted for significant differences in characteristics between the groups. RESULTS: Overall, 13283 individuals met eligibility criteria and 78.8% (n = 10473) of the population was enrolled in Medicaid pre-release. Compared with those enrolled in Medicaid prior to release, those enrolled post-release were more likely to have an emergency department visit (59.6% versus 57.5%, p = 0.04) and hospitalization (17.9% versus 15.9%, p = 0.01) and less likely to receive outpatient mental health services (12.3% versus 15.2%, p<0.001) and prescription drugs. Compared with those enrolled in Medicaid prior to release, those enrolled post-release had a significantly longer time to receiving many services including a primary care visit (adjusted mean difference: 42.2 days [95% CI: 37.9 to 46.5; p<0.001]), outpatient mental health services (42.8 days [95% CI: 31.3 to 54.4; p<0.001]), outpatient substance use disorder service (20.6 days [95% CI: 2.0 to 39.2; p = 0.03]), and medication for opioid use disorder (40.4 days [95% CI: 23.7 to 57.1; p<0.001]) as well as inhaled bronchodilators and corticosteroids (63.8 days [95% CI: 49.3 to 78.3, p<0.001]), antipsychotics (62.9 days [95% CI: 50.8 to 75.1; p<0.001]), antihypertensives (60.5 days [95% CI: 50.7 to 70.3; p<0.001]), and antidepressants (52.3 days [95% CI: 44.1 to 60.5; p<0.001]). CONCLUSION: Compared with Medicaid enrollment post-release, pre-release Medicaid enrollment was associated with higher proportions of, and faster access to, a wide variety of health services. Regardless of enrollment status, we found prolonged times between release and receipt of time-sensitive behavioral health services and prescription medications.


Subject(s)
Mental Health Services , Prisoners , United States , Humans , Medicaid , Retrospective Studies , Louisiana
3.
Annu Rev Public Health ; 44: 407-428, 2023 04 03.
Article in English | MEDLINE | ID: mdl-36542770

ABSTRACT

Mass incarceration is a sociostructural driver of profound health inequalities in the United States. The political and economic forces underpinning mass incarceration are deeply rooted in centuries of the enslavement of people of African descent and the genocide and displacement of Indigenous people and is inextricably connected to labor exploitation, racial discrimination, the criminalization of immigration, and behavioral health problems such as mental illness and substance use disorders. This article focuses on major public health crises and advances in state and federal prisons and discusses a range of practical strategies for health scholars, practitioners, and activists to promote the health and dignity of incarcerated people. It begins by summarizing the historical and sociostructural factors that have led to mass incarceration in the United States. It then describes the ways in which prison conditions create or worsen chronic, communicable, and behavioral health conditions, while highlighting priority areas for public health research and intervention to improve the health of incarcerated people, including decarceral solutions that can profoundly minimize-and perhaps one day help abolish-the use of prisons.


Subject(s)
Prisoners , Substance-Related Disorders , Humans , United States , Prisons , Public Health
5.
Respir Care ; 67(11): 1385-1395, 2022 11.
Article in English | MEDLINE | ID: mdl-35820701

ABSTRACT

BACKGROUND: Recent studies reported that children on mechanical ventilation who were managed with an analgosedation approach and standardized extubation readiness testing experienced better outcomes, including decreased delirium and invasive mechanical ventilation duration. METHODS: This was a quality improvement project in a 24-bed pediatric ICU within a single center, including subjects ≤ 18 years old who required invasive mechanical ventilation via an oral or nasal endotracheal tube. The aim was to decrease the invasive mechanical ventilation duration for all the subjects by 25% within 9 months through the development and implementation of bundled benzodiazepine-sparing analgosedation and extubation readiness testing clinical pathways. RESULTS: In the pre-implementation cohort, there were 274 encounters, with 253 (92.3%) that met inclusion for ending in an extubation attempt. In the implementation cohort, there were 367 encounters with 332 (90.5%) that ended in an extubation attempt. The mean invasive mechanical ventilation duration decreased by 23% (Pre 3.95 d vs Post 3.1 d; P = .039) after the implementation without a change in the mean pediatric ICU length of stay (Pre 7.5 d vs Post 6.5 d; P = .42). No difference in unplanned extubation (P > .99) or extubation failure rates (P = .67) were demonstrated. Sedation levels as evaluated by the mean State Behavioral Scale were similar (Pre -1.0 vs Post -1.1; P = .09). The median total benzodiazepine dose administered decreased by 75% (Pre 0.4 vs Post 0.1 mg/kg/ventilated day; P < .001). No difference in narcotic withdrawal (Pre 17.8% vs Post 16.4%; P = .65) or with delirium treatment (Pre 5.5% vs Post 8.7%; P = .14) was demonstrated. CONCLUSIONS: A multidisciplinary, bundled benzodiazepine-sparing analgosedation and extubation readiness testing approach resulted in a reduction in mechanical ventilation duration and benzodiazepine exposure without impacting key balancing measures. External validity needs to be evaluated in similar centers and consensus on best practices developed.


Subject(s)
Airway Extubation , Delirium , Humans , Child , Adolescent , Respiration, Artificial/methods , Benzodiazepines , Narcotics
6.
Environ Manage ; 69(3): 588-599, 2022 03.
Article in English | MEDLINE | ID: mdl-35031890

ABSTRACT

Environmental management involves the complex interaction between identifying the causes of problems and implementing solutions. Our exploratory study draws on attribution theory to analyze the causal attributions among community members experiencing frequent and intensifying harmful algal blooms in a lake of western New York State. Our interviews (n = 21) revealed that causal attributions were grounded in observation but that scientific observations led to very different causal attributions than direct observations among a subset of the lay public. Some community members also developed causal attributions based on their social relationships. Differences in causal attributions became the basis of widespread intracommunity disagreement, which in turn hampered management efforts. Our work demonstrates the need for meaningful public engagement in water management-engagement that addresses causal beliefs within the community, even if those beliefs may not align with scientific understandings.


Subject(s)
Harmful Algal Bloom , Lakes , New York
7.
Conserv Biol ; 34(6): 1560-1570, 2020 12.
Article in English | MEDLINE | ID: mdl-32233119

ABSTRACT

We devised a practical method for integrating information on 2 marine invasive species using 3 different approaches: standardized ecological monitoring, online-reporting databases, and surveys of anglers and crabbers. Focusing on 2 recently introduced species with different characteristics, the Asian shore crab (Hemigrapsus sanguineus) and Chinese mitten crab (Eriocheir sinensis), in the Hudson-Raritan watershed of New York and New Jersey, we used sensitivity analyses to explore the relative contribution of each information source to knowledge of species abundance and distribution. All 3 information sources contributed something unique to understanding abundance and distribution of the introduced crabs. Online and survey data on Asian shore crabs significantly affected predictions of abundance, whereas monitoring data did not. When survey data were omitted, abundance estimates were unchanged over time, but when they were included, the model predicted an increased abundance in 2012. All 3 data sets for the Asian shore crab significantly affected estimates of species coverage; surveys had the biggest influence, increasing range size by 4097.25 km2 . For the catadromous Chinese mitten crab, ecological monitoring data collected in freshwater shortly after the original sighting significantly shaped model estimates for abundance and documented the establishment phase of the mitten crab in an area outside the spatial scope of the surveyed resource users. However, the survey data significantly enlarged mitten crab range-size estimates by 6498.01 km2 . By demonstrating that data integration produced an image of the invasion process that would not have emerged had we used any 1 method individually, model results provide evidence for the advantages of an interdisciplinary approach.


Acoplamiento entre los Dominios de Información para Mejorar el Entendimiento Ecológico de las Invasiones Biológicas en un Ecosistema Marino Resumen Diseñamos un método práctico para integrar la información sobre dos especies marinas invasoras usando tres estrategias diferentes: el monitoreo ecológico estandarizado, las bases de datos de reporte en línea y las encuestas realizadas a pescadores y recolectores de cangrejos. Con un enfoque sobre dos especies con características diferentes, Hemigraspus sanguineus y Eriocheir sinensis, introducidas recientemente en la vertiente Hudson-Raritan de Nueva York y Nueva Jersey, usamos varios análisis de sensibilidad para explorar la contribución relativa de cada fuente de información para el conocimiento sobre la abundancia y distribución de las especies. Las tres fuentes de información contribuyeron algo único al entendimiento de la abundancia y distribución de los cangrejos introducidos. Los datos obtenidos en línea y de las encuestas sobre la especie H. sanguineus afectaron significativamente las predicciones de su abundancia, mientras que los datos de monitoreo no lo hicieron. Cuando se omitieron los datos de las encuestas, las estimaciones de abundancia no sufrieron modificaciones con el tiempo, pero cuando incluimos esos datos, el modelo pronosticó un incremento en la abundancia en 2012. Los tres conjuntos de datos de la especie H. sanguineus afectaron significativamente las estimaciones de la cobertura de la especie; las encuestas tuvieron la mayor influencia incrementando el tamaño de la distribución por 4097.25 km2 . Para la especie catádroma E. sinensis, los datos del monitoreo ecológico recolectados en agua dulce poco tiempo después del avistamiento original moldearon significativamente las estimaciones del modelo para la abundancia y documentaron la fase de establecimiento de esta especie en un área fuera del alcance espacial de los usuarios del recurso encuestados. Sin embargo, los datos de las encuestas agrandaron considerablemente las estimaciones de la distribución de E. sinensis por 6498.01 km2 . Con la demostración de que la integración de datos produjo una imagen del proceso de invasión que no habría surgido de haber usado un método individualmente, los resultados del modelo proporcionan evidencias para las ventajas de una estrategia interdisciplinaria.


Subject(s)
Brachyura , Ecosystem , Animals , Conservation of Natural Resources , Introduced Species , New Jersey
8.
Environ Manage ; 65(5): 689-701, 2020 05.
Article in English | MEDLINE | ID: mdl-32086548

ABSTRACT

Little is known about the conservation of intermittent and ephemeral streams on private lands despite the importance of these waterways for ecosystem and hydrologic outcomes. Our case study of a watershed of central New York State considers landowners' attitudes toward perennial and intermittent streams on their property. We combine social science survey responses with aerial imagery to assess the underlying drivers of landowners' attitudes about their streams, and the extent to which these attitudes shape riparian conservation behaviors on their properties. We find that stream flow regularity directly and positively shapes landowners' stream attitudes, with landowners of perennially flowing streams holding their streams in higher regard than landowners with streams of intermittent flows. Landowners with forest and wetlands as the primary land cover had more riparian buffer coverage on their properties than agricultural landowners. Landowners with a weaker perceived land use efficacy also had greater buffer coverage. Our findings suggest that landowners in headwater regions do not perceive their influence on downstream water quality, and that outreach efforts should emphasize the importance and conservation of headwater streams and associated water quality outcomes.


Subject(s)
Ecosystem , Forests , Agriculture , Attitude , Conservation of Natural Resources , New York
9.
Ambio ; 47(3): 284-297, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29030755

ABSTRACT

The impact of Hurricane Sandy on the Hudson-Raritan estuary (HRE) provided a valuable case study for exploring interactions between long-term environmental degradation, new climatic disturbance stressors, and human behavioral responses. We extend previous research on the ecological effects of major storms to compare water quality and biological parameters three years before and three years after Hurricane Sandy and consider how ecosystem shifts relate to anglers' perceptions. Results indicate that water clarity and nutrients returned to pre-storm conditions in about one year, while shifts in the biological community, including a significant increase in harmful algal species and declines in zooplankton and Atlantic menhaden, persisted for multiple years, and anglers continued to fish amidst ecosystem decline. Biotic recovery time in the HRE was longer than reports for other shallow estuaries frequently disturbed by hurricanes. Ecological and social responses suggest that the post-storm regime shifts and continued fishing pressure could further environmental degradation.


Subject(s)
Cyclonic Storms , Ecosystem , Estuaries , Animals , Human Activities , Humans , Population Dynamics , Zooplankton
10.
Appl Radiat Isot ; 130: 131-139, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28963960

ABSTRACT

The goal of this study was to investigate the production, purification and immobilization techniques for a 153Gd brachytherapy source. We have investigated the maximum attainable specific activity of 153Gd through the irradiation of Gd2O3 enriched to 30.6% 152Gd at McMaster Nuclear Reactor. The advantage of producing 153Gd through this production pathway is the possibility to irradiate pre-sealed pellets of 152Gd enriched Gd2O3, thereby removing the need to perform chemical separation with large quantities of radio-impurities. However, small amounts of long-lived impurities are produced from the irradiation of enriched 152Gd targets due to traces of Eu in the sample. If the amount of impurities produced is deemed unacceptable, 153Gd can be isolated as an aqueous solution, chemically separated from impurities and loaded onto a sorbent with a high affinity for Gd before encapsulation.


Subject(s)
Brachytherapy/methods , Gadolinium/therapeutic use , Neutron Capture Therapy/methods , Radioisotopes/therapeutic use , Gadolinium/isolation & purification , Humans , Nuclear Reactors , Radioisotopes/isolation & purification , Radiotherapy Dosage
11.
Appl Radiat Isot ; 110: 70-73, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26773819

ABSTRACT

The goals of the present study were to develop a (170)Tm radioisotope and generate a K XRF spectrum of mercury. Thulium foil and thulium oxide powder were both tested for impurities and the latter was found to be a better prospect for further studies. The (170)Tm radioisotope was developed from thulium oxide powder following the method of disolution and absorption. A suitable source holder and collimator were also designed based on Monte Carlo simulations. Using the radioisotope thus developed, a mercury XRF spectrum was successfully generated.


Subject(s)
Mercury/analysis , Radioisotopes , Spectrometry, X-Ray Emission/methods , Thulium , Environmental Monitoring/methods , Humans , Mercury/toxicity , Occupational Exposure/analysis , Phantoms, Imaging
12.
Neuromolecular Med ; 16(1): 150-60, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24101586

ABSTRACT

The success of future intervention strategies for Alzheimer's disease (AD) will likely rely on the development of treatments starting early in the disease course, before irreversible brain damage occurs. The pre-symptomatic stage of AD occurs at least one decade before the clinical onset, highlighting the need for validated biomarkers that reflect this early period. Reliable biomarkers for AD are also needed in research and clinics for diagnosis, patient stratification, clinical trials, monitoring of disease progression and the development of new treatments. Changes in the lysosomal network, i.e., the endosomal, lysosomal and autophagy systems, are among the first alterations observed in an AD brain. In this study, we performed a targeted search for lysosomal network proteins in human cerebrospinal fluid (CSF). Thirty-four proteins were investigated, and six of them, early endosomal antigen 1 (EEA1), lysosomal-associated membrane proteins 1 and 2 (LAMP-1, LAMP-2), microtubule-associated protein 1 light chain 3 (LC3), Rab3 and Rab7, were significantly increased in the CSF from AD patients compared with neurological controls. These results were confirmed in a validation cohort of CSF samples, and patients with no neurochemical evidence of AD, apart from increased total-tau, were found to have EEA1 levels corresponding to the increased total-tau levels. These findings indicate that increased levels of LAMP-1, LAMP-2, LC3, Rab3 and Rab7 in the CSF might be specific for AD, and increased EEA1 levels may be a sign of general neurodegeneration. These six lysosomal network proteins are potential AD biomarkers and may be used to investigate lysosomal involvement in AD pathogenesis.


Subject(s)
Alzheimer Disease/cerebrospinal fluid , Cerebrospinal Fluid Proteins/cerebrospinal fluid , Lysosomal Membrane Proteins/cerebrospinal fluid , Lysosomal-Associated Membrane Protein 2/cerebrospinal fluid , Lysosomes/chemistry , Microtubule-Associated Proteins/cerebrospinal fluid , Vesicular Transport Proteins/cerebrospinal fluid , rab GTP-Binding Proteins/cerebrospinal fluid , rab3 GTP-Binding Proteins/cerebrospinal fluid , Adult , Aged , Aged, 80 and over , Albumins/cerebrospinal fluid , Amyloid beta-Peptides/cerebrospinal fluid , Autophagy , Biomarkers/cerebrospinal fluid , Endosomes/chemistry , Female , Humans , Male , Middle Aged , Nerve Tissue Proteins/cerebrospinal fluid , Peptide Fragments/cerebrospinal fluid , Phagosomes/chemistry , rab7 GTP-Binding Proteins , tau Proteins/cerebrospinal fluid
13.
Dose Response ; 11: 498-516, 2013.
Article in English | MEDLINE | ID: mdl-24298227

ABSTRACT

In this study, we aimed to establish the emission of UV photons when HPV-G cells and associated materials (such as the cell substrate and cell growth media) are exposed to low LET radiation. The potential role of UV photons in the secondary triggering of biological processes led us to hypothesize that the emission and absorption of photons at this wavelength explain some radiation induced "bystander effects" that have previously been thought to be chemically mediated. Cells were plated in Petri-dishes of two different sizes, having different thicknesses of polystyrene (PS) substrate, and were exposed to ß-radiation from (90)Y produced by the McMaster Nuclear Reactor. UV measurements were performed using a single photon counting system employing an interference-type filter for selection of a narrow wavelength range, 340±5 nm, of photons. Exposure of the cell substrates (which were made of polystyrene) determined that UV photons were being emitted as a consequence of ß particle irradiation of the Petri-dishes. For a tightly collimated ß-particle beam exposure, we observed 167 photons in the detector per unit µCi in the shielded source for a 1.76 mm thick substrate and 158 photons/µCi for a 0.878 mm thick substrate. A unit µCi source activity was equivalent to an exposure to the substrate of 18 ß-particles/cm(2) in this case. The presence of cells and medium in a Petri-dish was found to significantly increase (up to a maximum of 250%) the measured number of photons in a narrow band of wavelengths of 340±5 nm (i.e. UVA) as compared to the signal from an empty control Petri-dish. When coloured growth medium was added to the cells, it reduced the measured count rate, while the addition of transparent medium in equal volume increased the count rate, compared to cells alone. We attribute this to the fact that emission, scattering and absorption of light by cells and media are all variables in the experiment. Under collimated irradiation conditions, it was observed that increasing cell density in medium of fixed volume resulted in a decrease in the observed light output. This followed a roughly exponential decline. We suggest that this may be due to increased scattering at the cell boundary and absorption of the UV in the cells. We conclude that we have measured UVA emitted by cells, cell medium and cell substrates as a consequence of their irradiation by low LET ß-particle radiation. We suggest that these secondary UV photons could lead to effects in non-targetted cells. Some effects that had previously been attributed to a chemically mediated "bystander effect" may in fact be due to secondary UV emission. Some radiation bystander effect studies may require re-interpretation as this phenomenon of UV emission is further investigated.

14.
Environ Manage ; 50(5): 849-60, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22926239

ABSTRACT

Headwater streams are critical components of the stream network, yet landowner perceptions, attitudes, and property management behaviors surrounding these intermittent and ephemeral streams are not well understood. Our research uses the concept of watershed disproportionality, where coupled social-biophysical conditions bear a disproportionate responsibility for harmful water quality outcomes, to analyze the potential influence of riparian landowner perceptions and attitudes on water quality in headwater regions. We combine social science survey data, aerial imagery, and an analysis of spatial point processes to assess the relationship between riparian landowner perceptions and attitudes in relation to stream flow regularity. Stream flow regularity directly and positively shapes landowners' water quality concerns, and also positively influences landowners' attitudes of stream importance-a key determinant of water quality concern as identified in a path analysis. Similarly, riparian landowners who do not notice or perceive a stream on their property are likely located in headwater regions. Our findings indicate that landowners of headwater streams, which are critical areas for watershed-scale water quality, are less likely to manage for water quality than landowners with perennial streams in an obvious, natural channel. We discuss the relationships between streamflow and how landowners develop understandings of their stream, and relate this to the broader water quality implications of headwater stream mismanagement.


Subject(s)
Rivers , Water Quality , Water/analysis
15.
Dalton Trans ; 39(35): 8128-31, 2010 Sep 21.
Article in English | MEDLINE | ID: mdl-20694253

ABSTRACT

Carboranes form stable complexes with the [M(CO)(3)](+) (M = (99m)Tc, Re) core and are viable ligands for the development of targeted radiopharmaceuticals. (99m)Tc-carborane complexes were found to exhibit substantially different 1,2-->1,7 cage isomerisation behaviour than their Re counterparts, challenging the validity of the routine use of rhenium as a surrogate for the development of technetium-99m based molecular imaging agents.


Subject(s)
Boranes/chemistry , Coordination Complexes/chemistry , Radiopharmaceuticals/chemistry , Rhenium/chemistry , Technetium/chemistry , Isomerism , Isotope Labeling , Tomography, Emission-Computed, Single-Photon
16.
Nucl Med Biol ; 36(8): 907-17, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19875047

ABSTRACT

INTRODUCTION: The aim of this work was to investigate the relative radiolabelling kinetics and affinity of a series of ligands for the [(99m)Tc(CO)(3)](+) core, both in the absence and in the presence of competing donors. This information was used to select a suitable ligand for radiolabelling complex peptide-based targeting vectors in high yield under mild conditions. METHODS: A series of alpha-N-Fmoc-protected lysine derivatives bearing two heterocyclic donor groups at the epsilon-amine (1a, 2-pyridyl; '1b, quinolyl; '1c, 6-methoxy-2-pyridyl; 1d, 2-thiazolyl; 1e, N-methylimidazolyl; '1f, 3-pyridyl) were synthesized and labelled with (99m)Tc. A resin-capture purification strategy for the separation of residual ligand from the radiolabelled product was also developed. The binding affinities of targeted peptides 4, 5a and 5b for uPAR were determined using flow cytometry. RESULTS: Variable temperature radiolabelling reactions using 1a-'1f and [(99m)Tc(CO)(3)](+) revealed optimal kinetics and good selectivity for compounds '1a and 1d; in the case of '1a, 1d, and 1e, the labelling can be conducted at ambient temperature. The utility of this class of ligands was further demonstrated by the radiolabelling of a cyclic peptide that is known to target the serine protease receptor uPAR; essentially quantitative incorporation of (99m)Tc occurred exclusively at the SAAC site, despite the presence of a His residue, and without disruption of the disulfide bond. CONCLUSION: A series of single amino acid chelate (SAAC) ligands have been evaluated for their ability to incorporate (99m)Tc into peptides. The lead agent to emerge from this work is the thiazole SAAC derivative 1d which has demonstrated the ability to regioselectively label the widest range of peptides.


Subject(s)
Amino Acids/pharmacokinetics , Peptides, Cyclic/pharmacokinetics , Receptors, Urokinase Plasminogen Activator/metabolism , Technetium/pharmacokinetics , Amino Acids/chemistry , Chelating Agents/chemistry , Humans , Isotope Labeling/methods , Peptides, Cyclic/chemistry , Radiopharmaceuticals/chemical synthesis , Radiopharmaceuticals/pharmacokinetics , Technetium/chemistry , U937 Cells
18.
Dalton Trans ; (38): 4240-51, 2007 Oct 10.
Article in English | MEDLINE | ID: mdl-17893811

ABSTRACT

The role of carboranes in medicinal chemistry has diversified in recent years and now extends into areas of drug discovery, molecular imaging, and targeted radionuclide therapy. An introduction to carborane chemistry is provided to familiarize the non-expert with some key properties of these molecules, followed by an overview of current medicinally-orientated research involving carboranes. The broad-ranging nature of this research is illustrated, with emphasis placed on recent highlights and advances in this field.


Subject(s)
Boranes/chemistry , Boranes/pharmacology , Amyloid/antagonists & inhibitors , Amyloid/metabolism , Boranes/therapeutic use , Diagnostic Imaging , Drug Design , Estrogen Receptor Modulators/chemistry , Estrogen Receptor Modulators/pharmacology , Estrogen Receptor Modulators/therapeutic use , Receptors, Estrogen/agonists , Receptors, Estrogen/antagonists & inhibitors , Receptors, Estrogen/metabolism
19.
Inorg Chem ; 46(6): 2148-58, 2007 Mar 19.
Article in English | MEDLINE | ID: mdl-17302405

ABSTRACT

A series of tricarbonyl rhenacarboranes {[M][Re(CO)3(RR'C2B9H9)]} (M = Na, K) were synthesized in water using microwave radiation with reaction times of less than 15 min. The novel complexes were isolated in good yields (57-94%) as either 3,1,2-(R = H: R' = CH2Pyr 6; R' = CH2Cy, 20) or 2,1,8-(R = H: R' = H, 4; R' = CH2PyrMe 12; R' = CH2PyrH, 13; R' = Pyr, 15; R' = Ph, 17; R = R' = Bn, 19) metallacarboranes and characterized by multinuclear (1H, 11B, 13C) and NOE NMR spectroscopy, IR spectroscopy, mass spectrometry, and X-ray crystallography in the case of compounds 12 and 13. Carborane cage isomerization from the original 1,2 configuration to the 1,7 orientation occurred in cases where significant steric crowding was present at the metal center. Incorporation of a methylene spacer between the carborane cage and the six-membered ring as in 7 and 20 decreased steric strain such that the 3,1,2 configuration was maintained. Conversion of the 3,1,2 complex 6 to the 2,1,8 isomers 12 and 13 takes place at room temperature upon methylation or protonation of the pyridyl ring, indicating that electronic effects also play a significant role in the isomerization process.


Subject(s)
Boranes/chemical synthesis , Microwaves , Boranes/chemistry , Isomerism , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Structure , Spectrophotometry, Infrared , X-Ray Diffraction
20.
Chem Pharm Bull (Tokyo) ; 54(9): 1235-8, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16946526

ABSTRACT

A new sesquiterpene-lactone (nubenolide) belonging to the guaianolide class along with its acetate (nubenolide acetate) and a dimer (bisnubenolide) have been isolated from Salvia nubicola collected from Quetta, Pakistan. Structures of all three new metabolites were elucidated with the aid of spectroscopic techniques including 2D-NMR. However, the structure of nubenolide was finally confirmed via single-crystal X-ray diffraction method.


Subject(s)
Cycloheptanes/chemistry , Lactones/chemistry , Salvia/chemistry , Sesquiterpenes, Guaiane/chemistry , Sesquiterpenes/chemistry , Cycloheptanes/classification , Cycloheptanes/isolation & purification , Lactones/isolation & purification , Magnetic Resonance Spectroscopy/methods , Models, Molecular , Molecular Conformation , Sensitivity and Specificity , Sesquiterpenes/isolation & purification , Sesquiterpenes, Guaiane/classification , Sesquiterpenes, Guaiane/isolation & purification , Species Specificity , Stereoisomerism , X-Ray Diffraction
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