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1.
Data Brief ; 43: 108414, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35799857

RESUMO

This paleoenvironmental database features postglacial lake-sediment records from 31 study sites located across New England. The study sites span an environmental gradient from the cooler, northern and inland part of the region to the warmer, southern and coastal areas of New England. Sediment-core chronologies were determined using 14C dating, 210Pb analysis, and pollen evidence. Detailed analyses of sediment lithology, pollen, and charcoal were used to reconstruct changes in climate, vegetation, and fire at centennial temporal scales and subregional spatial scales for the last 14,000 years. Analyses of paleoenvironmental data provide insights into the rates, patterns, and drivers of ecosystem change, helping us anticipate future ecosystem dynamics and guiding present-day conservation strategies and land management.

2.
Am J Health Syst Pharm ; 79(Suppl 3): S86-S93, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35605142

RESUMO

PURPOSE: To evaluate the efficacy and safety of a pharmacist-managed protocol for transitioning critically ill patients from intravenous (IV) to subcutaneous insulin. METHODS: This single-center, retrospective, observational study included patients admitted to the medical or surgical/trauma intensive care unit who received a continuous infusion of IV insulin from January 2019 to April 2021. Patients were excluded if they were less than 18 years old, pregnant, or incarcerated or received IV insulin for the diagnosis of diabetic ketoacidosis, hyperglycemic hyperosmolar state, calcium channel blocker or ß-blocker overdose, or hypertriglyceridemia. The primary outcome was to evaluate the percentage of blood glucose (BG) concentrations within the target range of 70 to 150 mg/dL within 48 hours of the transition to subcutaneous insulin. Secondary outcomes included the percentage of BG concentrations within the goal range following transition at 0 to 12 hours and 12 to 24 hours, the incidence of hypo- and hyperglycemia, and the percentage of patients requiring dose adjustments after the initial transition. RESULTS: Pharmacists were able to achieve BG concentrations in the target range for 53% of transitions at 12 hours, 40% of transitions at 24 hours, and 47% of transitions at 48 hours. With respect to safety endpoints, the pharmacist-managed group had a low rate of hypoglycemia (1.0%) and no severe hypoglycemia. Hyperglycemia was reported for 28% of BG concentrations while severe hyperglycemia was reported for 27%. Pharmacists transitioned patients to an average of 63% of the 24-hour total daily dose of insulin as basal insulin. CONCLUSION: Pharmacists can effectively and safely transition critically ill patients from IV to subcutaneous insulin utilizing a standardized protocol.


Assuntos
Hiperglicemia , Hipoglicemia , Adolescente , Adulto , Glicemia , Estado Terminal/terapia , Humanos , Hiperglicemia/diagnóstico , Hiperglicemia/tratamento farmacológico , Hipoglicemia/induzido quimicamente , Hipoglicemia/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Infusões Intravenosas , Insulina/efeitos adversos , Estudos Observacionais como Assunto , Farmacêuticos , Estudos Retrospectivos
3.
J Am Pharm Assoc (2003) ; 61(5): 623-631.e3, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34045156

RESUMO

BACKGROUND: Widespread use of prescription opioids is associated with adverse outcomes. OBJECTIVE: To identify factors associated with adverse health outcomes and health care use using a statewide health information exchange. METHODS: This is a retrospective cohort study using the Indiana Network for Patient Care. Adult opioid-naive patients who received an opioid prescription between January 2012 and December 2017 were included. The outcomes included (1) a composite outcome of any combination of opioid abuse, dependence, or overdose, (2) all-cause mortality, and (3) health care use. Independent variables included opioid dosage, dispensed amount, days supply, concurrent use of short-acting (SA) and long-acting (LA) opioids, and concurrent use with benzodiazepine or gabapentinoids. Additional variables included patients' age, sex, race, modified Charlson Comorbidity Index score, mental health conditions, and medications for opioid use disorders. Factors associated with composite outcome and mortality were identified using Cox proportional hazards and reported as adjusted hazard ratio (aHR) and 95% CI. Factors associated with health care use were identified using Poisson regression and reported as adjusted incidence rate ratio (aIRR) and 95% CI. RESULTS: 1,328,287 opioid prescriptions were identified for 341,722 patients. Opioid-related factors associated with the composite outcome, mortality, and hospitalizations, respectively, included opioid dosage (aHR 1.003 [95% CI 1.001-1.006]; aHR not applicable; aIRR 1.07 [1.06-1.08]), opioid days supply (aHR 1.03 [1.02-1.03]; aHR 1.009 [1.005-1.014]; aIRR 0.94 [0.92-0.96]), concurrent SA/LA opioids (aHR 2.12 [1.78-2.54]; aHR 1.40 [1.14-1.70]; aIRR 1.40 [1.37-1.42]), and use of benzodiazepines/gabapentinoids (aHR 1.68 [1.38-2.04]; aHR 1.23 [1.01-1.51]; aIRR 1.25 [1.23-1.27]). CONCLUSION: Many factors are associated with poor health outcomes, especially concurrent use of SA and LA opioids and overlapping prescriptions of opioids with benzodiazepines or gabapentinoids. Identification of factors associated with adverse outcomes may help identify patients at risk for poor outcomes and could inform possible interventions.


Assuntos
Analgésicos Opioides , Troca de Informação em Saúde , Adulto , Analgésicos Opioides/efeitos adversos , Benzodiazepinas/efeitos adversos , Humanos , Avaliação de Resultados em Cuidados de Saúde , Padrões de Prática Médica , Estudos Retrospectivos
4.
J Burn Care Res ; 41(5): 1004-1008, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32594168

RESUMO

Inhalation injury causes significant morbidity and mortality secondary to compromise of the respiratory system as well as systemic effects limiting perfusion and oxygenation. Nebulized heparin reduces fibrin cast formation and duration of mechanical ventilation in patients with inhalation injury. To date, no study has compared both dosing strategies of 5000 and 10,000 units to a matched control group. This multicenter, retrospective, case-control study included adult patients with bronchoscopy-confirmed inhalation injury. Each control patient, matched according to age and percent of total body surface area, was matched to a patient who received 5000 units and a patient who received 10,000 units of nebulized heparin. The primary endpoint of the study was duration of mechanical ventilation. Secondary endpoints included 28-day mortality, ventilator-free days in the first 28 days, difference in lung injury scores, length of hospitalization, incidence of ventilator-associated pneumonia, and rate of major bleeding. Thirty-five matched patient trios met inclusion criteria. Groups were well-matched for age (P = .975) and total body surface area (P = .855). Patients who received nebulized heparin, either 5000 or 10,000 units, had 8 to 11 less days on the ventilator compared to controls (P = .001). Mortality ranged from 3 to 14% overall and was not statistically significant between groups. No major bleeding events related to nebulized heparin were reported. Mechanical ventilation days were significantly decreased in patients who received 5000 or 10,000 units of nebulized heparin. Nebulized heparin, either 5000 units or 10,000 units, is a safe and effective treatment for inhalation injury.


Assuntos
Anticoagulantes/administração & dosagem , Queimaduras por Inalação/terapia , Heparina/administração & dosagem , Nebulizadores e Vaporizadores , Respiração Artificial , Administração por Inalação , Adulto , Broncoscopia , Queimaduras por Inalação/mortalidade , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida
5.
Burns ; 46(2): 370-376, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31420265

RESUMO

Burn patients frequently require autograft harvesting to facilitate wound healing, often resulting in significant pain. Liposomal bupivacaine is indicated for administration into a surgical site to produce postsurgical analgesia. The objective of this study was to evaluate efficacy, safety, and duration of postoperative analgesia with liposomal bupivacaine for donor site pain in burn patients. This was an observational, case-control study including adult patients with <20% total body surface area (TBSA) burned who received liposomal bupivacaine for postoperative pain management after autograft harvesting from lower extremity donor site(s). Patients from the case group were matched to historical control patients treated with traditional pain management. The primary outcome was the cumulative pain scores on postoperative day one measured by the area under the curve (AUC0-24). Secondary outcomes included AUC0-72, total milligram morphine equivalents (MME), length of stay, and adverse events. Data were collected in 36 patients who received liposomal bupivacaine, with 21 patients eligible for matching to historical controls. Patients included in the intervention and control groups were well-matched at baseline. Patients in the intervention group had a significantly lower median (IQR) AUC0-24 [578 (408,740) vs. 680 (544,803); p = 0.05] and shorter length of stay [4 days (1,9.5) vs. 6 days (318); p = 0.01]. No differences in adverse events related to the administration of liposomal bupivacaine or opioid-related adverse events were observed. Results indicate liposomal bupivacaine is safe and effective in burn patients. The results of this study add to the limited body of literature examining efficacy in this population.


Assuntos
Anestésicos Locais/administração & dosagem , Bupivacaína/administração & dosagem , Queimaduras/cirurgia , Dor Pós-Operatória/prevenção & controle , Coleta de Tecidos e Órgãos/métodos , Sítio Doador de Transplante , Adulto , Analgésicos Opioides/uso terapêutico , Estudos de Casos e Controles , Feminino , Humanos , Tempo de Internação , Lipossomos , Masculino , Pessoa de Meia-Idade , Manejo da Dor , Dor Pós-Operatória/tratamento farmacológico , Estudos Prospectivos , Transplante de Pele , Transplante Autólogo , Resultado do Tratamento
6.
Proc Natl Acad Sci U S A ; 116(13): 5985-5990, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30858312

RESUMO

Climate variations in the North Atlantic region can substantially impact surrounding continents. Notably, the Younger Dryas chronozone was named for the ecosystem effects of abrupt changes in the region at circa (ca.) 12.9-11.7 ka (millennia before 1950 AD). Holocene variations since then, however, have been hard to diagnose, and the responsiveness of terrestrial ecosystems continues to be debated. Here, we show that Holocene climate variations had spatial patterns consistent with changes in Atlantic overturning and repeatedly steepened the temperature gradient between Nova Scotia and Greenland since >8 ka. The multicentury changes correlated with hydrologic and vegetation changes in the northeast United States, including when an enhanced temperature gradient coincided with subregional droughts indicated by water-level changes at multiple coastal lakes at 4.9-4.6, 4.2-3.9, 2.8-2.1, and 1.3-1.2 ka. We assessed the variability and its effects by replicating signals across sites, using converging evidence from multiple methods, and applying forward models of the systems involved. We evaluated forest responses in the northeast United States and found that they tracked the regional climate shifts including the smallest magnitude (∼5% or 50 mm) changes in effective precipitation. Although a long-term increase in effective precipitation of >45% (>400 mm) could have prevented ecological communities from equilibrating to the continuously changing conditions, our comparisons confirm stable vegetation-climate relationships and support the use of fossil pollen records for quantitative paleoclimate reconstruction. Overall, the network of records indicates that centennial climate variability has repeatedly affected the North Atlantic region with predictable consequences.

7.
New Phytol ; 217(2): 939-955, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29083043

RESUMO

Nonrandom collecting practices may bias conclusions drawn from analyses of herbarium records. Recent efforts to fully digitize and mobilize regional floras online offer a timely opportunity to assess commonalities and differences in herbarium sampling biases. We determined spatial, temporal, trait, phylogenetic, and collector biases in c. 5 million herbarium records, representing three of the most complete digitized floras of the world: Australia (AU), South Africa (SA), and New England, USA (NE). We identified numerous shared and unique biases among these regions. Shared biases included specimens collected close to roads and herbaria; specimens collected more frequently during biological spring and summer; specimens of threatened species collected less frequently; and specimens of close relatives collected in similar numbers. Regional differences included overrepresentation of graminoids in SA and AU and of annuals in AU; and peak collection during the 1910s in NE, 1980s in SA, and 1990s in AU. Finally, in all regions, a disproportionately large percentage of specimens were collected by very few individuals. We hypothesize that these mega-collectors, with their associated preferences and idiosyncrasies, shaped patterns of collection bias via 'founder effects'. Studies using herbarium collections should account for sampling biases, and future collecting efforts should avoid compounding these biases to the extent possible.


Assuntos
Plantas/anatomia & histologia , Austrália , Geografia , Modelos Teóricos , Filogenia , Característica Quantitativa Herdável , Análise de Regressão , Viés de Seleção , Fatores de Tempo
8.
Ecology ; 98(3): 721-733, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27984662

RESUMO

The development of old-growth forests in northeastern North America has largely been within the context of gap-scale disturbances given the rarity of stand-replacing disturbances. Using the 10-ha old-growth Harvard Tract and its associated 90-year history of measurements, including detailed surveys in 1989 and 2009, we document the long-term structural and biomass development of an old-growth Tsuga canadensis-Pinus strobus forest in southern New Hampshire, USA following a stand-replacing hurricane in 1938. Measurements of aboveground biomass pools were integrated with data from second- and old-growth T. canadensis forests to evaluate long-term patterns in biomass development following this disturbance. Ecosystem structure across the Tract prior to the hurricane exhibited a high degree of spatial heterogeneity with the greatest levels of live tree basal area (70-129 m2 /ha) on upper west-facing slopes where P. strobus was dominant and intermixed with T. canadensis. Live-tree biomass estimates for these stratified mixtures ranged from 159 to 503 Mg/ha at the localized, plot scale (100 m2 ) and averaged 367 Mg/ha across these portions of the landscape approaching the upper bounds for eastern forests. Live-tree biomass 71 years after the hurricane is more uniform and lower in magnitude, with T. canadensis currently the dominant overstory tree species throughout much of the landscape. Despite only one living P. strobus stem in the 2009 plots (and fewer than five stems known across the entire 10-ha area), the detrital legacy of this species is pronounced with localized accumulations of coarse woody debris exceeding 237.7-404.2 m3 /ha where this species once dominated the canopy. These patterns underscore the great sizes P. strobus attained in pre-European landscapes and its great decay resistance relative to its forest associates. Total aboveground biomass pools in this 71-year-old forest (255 Mg/ha) are comparable to those in modern old-growth ecosystems in the region that also lack abundant white pine. Results highlight the importance of disturbance legacies in affecting forest structural conditions over extended periods following stand-replacing events and underscore that post-disturbance salvage logging can alter ecosystem development for decades. Moreover, the dominant role of old-growth P. strobus in live and detrital biomass pools before and after the hurricane, respectively, demonstrate the disproportionate influence this species likely had on carbon storage at localized scales prior to the widespread, selective harvesting of large P. strobus across the region in the 18th and 19th centuries.


Assuntos
Biomassa , Tempestades Ciclônicas , Pinus , Tsuga , Ecossistema , Florestas , New Hampshire , Árvores
9.
J Burn Care Res ; 38(1): 45-52, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27532613

RESUMO

Inhalation injury (IHI) causes significant morbidity and mortality in burn victims due to both local and systemic effects. Nebulized heparin promotes improvement in lung function and decreased mortality in IHI by reducing the inflammatory response and fibrin cast formation. The study objective was to determine if nebulized heparin 10,000 units improves lung function and decreases mechanical ventilation duration, mortality, and hospitalization length in IHI with minimal systemic adverse events. This retrospective, case-control study evaluated efficacy and safety of nebulized heparin administered to mechanically ventilated adults admitted within 48 hr of confirmed IHI. Nebulized heparin 10,000 units was administered Q4H for 7 days, or until extubation if sooner, alternating with albuterol and a mucolytic. Patients were matched on a case-by-case basis based on percent TBSA burn and age to patients from a historical group with IHI before heparin protocol implementation. The primary outcome was duration of mechanical ventilation. Secondary outcomes included lung injury score, ventilator-free days during the first 28 days, 28-day mortality, hospitalization length, ventilator-associated pneumonia incidence, bronchoscopy incidence, and bleeding events. Data were collected in 72 patients, 36 of which received nebulized heparin and 36 historical controls. Two patients from the heparin group and three patients from the control group died/were discharged while on the ventilator. Data were analyzed separately with 1) all subjects included and 2) with subjects who died/were discharged on the ventilator excluded. In the latter comparison, patients receiving nebulized heparin demonstrated a statistically significant decrease in median (interquartile range) duration of initial mechanical ventilation compared with controls [7.0 (4.0, 13.5) vs. 14.5 (5.3, 22.3) days; P = .044]. Patients in the heparin group had a significantly increased number of median (interquartile range) ventilator-free days in the first 28 days [21.0 (14.5-24.0) vs 13.5 (4.3-22.8) days; P = .031]. There were no differences in hospitalization length, lung injury score during the first 7 days post injury, 28-day mortality, ventilator-associated pneumonia rate, or bleeding events. Nebulized heparin 10,000 units in conjunction with a beta-agonist and mucolytic produced a significant decrease in duration of mechanical ventilation and increase in ventilator-free days in adult patients with IHI. Nebulized heparin was safe and did not result in an increase in bleeding events. To our knowledge, this is the first case-control study with matched cohorts based on age and %TBSA which are significant factors contributing to morbidity and mortality in IHI.


Assuntos
Anticoagulantes/administração & dosagem , Queimaduras por Inalação/terapia , Heparina/administração & dosagem , Nebulizadores e Vaporizadores , Administração por Inalação , Adulto , Albuterol/uso terapêutico , Broncodilatadores/uso terapêutico , Expectorantes/uso terapêutico , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Respiração Artificial , Estudos Retrospectivos , Resultado do Tratamento
10.
PLoS One ; 11(11): e0166783, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27893758

RESUMO

Historical extirpations have resulted in depauperate large herbivore assemblages in many northern forests. In eastern North America, most forests are inhabited by a single wild ungulate species, white-tailed deer (Odocoileus virginianus), and relationships between deer densities and impacts on forest regeneration are correspondingly well documented. Recent recolonizations by moose (Alces americanus) in northeastern regions complicate established deer density thresholds and predictions of browsing impacts on forest dynamics because size and foraging differences between the two animals suggest a lack of functional redundancy. We asked to what extent low densities of deer + moose would structure forest communities differently from that of low densities of deer in recently logged patch cuts of Massachusetts, USA. In each site, a randomized block with three treatment levels of large herbivores-no-ungulates (full exclosure), deer (partial exclosure), and deer + moose (control) was established. After 6-7 years, deer + moose reduced stem densities and basal area by 2-3-fold, Prunus pensylvanica and Quercus spp. recruitment by 3-6 fold, and species richness by 1.7 species (19%). In contrast, in the partial exclosures, deer had non-significant effects on stem density, basal area, and species composition, but significantly reduced species richness by 2.5 species on average (28%). Deer browsing in the partial exclosure was more selective than deer + moose browsing together, perhaps contributing to the decline in species richness in the former treatment and the lack of additional decline in the latter. Moose used the control plots at roughly the same frequency as deer (as determined by remote camera traps), suggesting that the much larger moose was the dominant browser species in terms of animal biomass in these cuts. A lack of functional redundancy with respect to foraging behavior between sympatric large herbivores may explain combined browsing effects that were both large and complex.


Assuntos
Cervos , Agricultura Florestal/métodos , Herbivoria , Árvores , Animais , Clima , Ecossistema , Florestas , Massachusetts , Caules de Planta , Densidade Demográfica , Especificidade da Espécie
11.
Ecol Appl ; 26(5): 1437-1455, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27755760

RESUMO

We review and synthesize information on invasions of nonnative forest insects and diseases in the United States, including their ecological and economic impacts, pathways of arrival, distribution within the United States, and policy options for reducing future invasions. Nonnative insects have accumulated in United States forests at a rate of ~2.5 per yr over the last 150 yr. Currently the two major pathways of introduction are importation of live plants and wood packing material such as pallets and crates. Introduced insects and diseases occur in forests and cities throughout the United States, and the problem is particularly severe in the Northeast and Upper Midwest. Nonnative forest pests are the only disturbance agent that has effectively eliminated entire tree species or genera from United States forests within decades. The resulting shift in forest structure and species composition alters ecosystem functions such as productivity, nutrient cycling, and wildlife habitat. In urban and suburban areas, loss of trees from streets, yards, and parks affects aesthetics, property values, shading, stormwater runoff, and human health. The economic damage from nonnative pests is not yet fully known, but is likely in the billions of dollars per year, with the majority of this economic burden borne by municipalities and residential property owners. Current policies for preventing introductions are having positive effects but are insufficient to reduce the influx of pests in the face of burgeoning global trade. Options are available to strengthen the defenses against pest arrival and establishment, including measures taken in the exporting country prior to shipment, measures to ensure clean shipments of plants and wood products, inspections at ports of entry, and post-entry measures such as quarantines, surveillance, and eradication programs. Improved data collection procedures for inspections, greater data accessibility, and better reporting would support better evaluation of policy effectiveness. Lack of additional action places the nation, local municipalities, and property owners at high risk of further damaging and costly invasions. Adopting stronger policies to reduce establishments of new forest insects and diseases would shift the major costs of control to the source and alleviate the economic burden now borne by homeowners and municipalities.


Assuntos
Florestas , Insetos/classificação , Espécies Introduzidas , Animais , Monitoramento Ambiental , Estados Unidos
12.
Ecol Evol ; 6(13): 4591-602, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27386099

RESUMO

Ungulates are leading drivers of plant communities worldwide, with impacts linked to animal density, disturbance and vegetation structure, and site productivity. Many ecosystems have more than one ungulate species; however, few studies have specifically examined the combined effects of two or more species on plant communities. We examined the extent to which two ungulate browsers (moose [Alces americanus]) and white-tailed deer [Odocoileus virginianus]) have additive (compounding) or compensatory (opposing) effects on herbaceous layer composition and diversity, 5-6 years after timber harvest in Massachusetts, USA. We established three combinations of ungulates using two types of fenced exclosures - none (full exclosure), deer (partial exclosure), and deer + moose (control) in six replicated blocks. Species composition diverged among browser treatments, and changes were generally additive. Plant assemblages characteristic of closed canopy forests were less abundant and assemblages characteristic of open/disturbed habitats were more abundant in deer + moose plots compared with ungulate excluded areas. Browsing by deer + moose resulted in greater herbaceous species richness at the plot scale (169 m(2)) and greater woody species richness at the subplot scale (1 m(2)) than ungulate exclusion and deer alone. Browsing by deer + moose resulted in strong changes to the composition, structure, and diversity of forest herbaceous layers, relative to areas free of ungulates and areas browed by white-tailed deer alone. Our results provide evidence that moderate browsing in forest openings can promote both herbaceous and woody plant diversity. These results are consistent with the classic grazing-species richness curve, but have rarely been documented in forests.

13.
AAPS J ; 18(4): 981-8, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27106837

RESUMO

Nifedipine is a BCS Class II drug used for treatment of hypertension and preterm labor. Large inter-patient variability in nifedipine absorption results in variable exposure among different patients. We conducted in vitro dissolution studies to compare nifedipine dissolution from immediate release (IR) capsules with different volumes of dissolution media. Results from dissolution studies were used to design a crossover study in healthy volunteers to evaluate the effect of coadministered water volume with nifedipine 10 mg IR capsules on nifedipine pharmacokinetics, especially absorption (C max, t max, and AUC0-6). Dissolution studies demonstrated that larger gastric fluid volumes result in enhanced nifedipine dissolution from 10 mg IR cosolvent capsules (73 vs. 17% in 200 and 100 mL simulated gastric fluid, respectively, at 30 min). The pharmacokinetic crossover study in healthy volunteers (N = 6) did not show a significant effect of the water volume administered with the capsule (50 vs. 250 mL) on C max, t max, or AUC0-6 of orally administered nifedipine IR capsules (10 mg). However, administration of large water volumes resulted in lower variability in nifedipine C max (47 vs. 70% for 250 and 50 mL, respectively). Administration of large water volumes with nifedipine 10 mg IR cosolvent capsules may reduce inter-individual variability in plasma exposure. Evaluation of similar effects in other BCS Class II drugs is recommended.


Assuntos
Nifedipino/administração & dosagem , Solubilidade , Cápsulas , Estudos Cross-Over , Humanos , Estômago
14.
Clin Pharmacokinet ; 54(7): 783-95, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25637173

RESUMO

BACKGROUND AND OBJECTIVE: Transparent reporting of all research is essential for assessing the validity of any study. Reporting guidelines are available and endorsed for many types of research but are lacking for clinical pharmacokinetic studies. Such tools promote the consistent reporting of a minimal set of information for end users, and facilitate knowledge translation of research. The objective of this study was to create a guideline to assist in the transparent and complete reporting of clinical pharmacokinetic studies. METHODS: Preliminary content to be considered was identified from a systematic search of the literature and regulatory documents. Stakeholders were identified to participate in a modified Delphi exercise and a virtual meeting to generate consensus for items considered essential in the reporting of clinical pharmacokinetic studies. The proposed checklist was pilot tested on 100 recently published clinical pharmacokinetic studies. Overall and itemized compliance with the proposed guidance was determined for each study. RESULTS: Sixty-eight stakeholders from nine countries consented to participate. Four rounds of a modified Delphi survey and a series of small virtual meetings were required to generate consensus for a 24-item checklist considered to be essential to the reporting of clinical pharmacokinetic studies. When applied to the 100 most recently published clinical pharmacokinetic studies, 45 were determined to be compliant with at least 80 % of the checklist items. Explanatory text was prepared using examples of compliant reporting from these and other relevant studies. CONCLUSIONS: The reader's ability to judge the validity of pharmacokinetic research can be greatly compromised by the incomplete reporting of study information. Using consensus methods, we have developed a tool to guide transparent and accurate reporting of clinical pharmacokinetic studies. Endorsement and implementation of these guidelines by researchers, clinicians and journals would promote more consistent reporting of these studies and allow for better assessment of utility for clinical applications.


Assuntos
Pesquisa Biomédica/normas , Guias como Assunto , Farmacocinética , Lista de Checagem , Técnica Delphi , Prova Pericial , Humanos , Farmacologia Clínica/normas , Projetos Piloto
15.
J Burn Care Res ; 36(6): 641-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25423436

RESUMO

Vancomycin pharmacokinetics are significantly altered following burn injury, requiring a higher total daily dose to achieve adequate serum concentrations. Wide interpatient variability necessitates close, frequent monitoring of serum concentrations for efficacy and safety. The aim of this study is to systematically evaluate published data regarding vancomycin pharmacokinetic alterations in burn patients, to determine whether evidence-based recommendations for dosing and monitoring can be formulated, and to identify future research opportunities. The systematic review included studies published in English, involved human subjects with at least a 10% TBSA burn who received vancomycin intravenously, and obtained serum concentration(s). Database searches returned 130 titles for review. Twelve studies met a priori inclusion criteria. The most common dosing regimens in adult and pediatric patients were 5 to 20 mg/kg/dose every 6 to 8 hours. Mean trough concentrations were 7.24 ± 1.5 mg/L. Only 12.5% of reported trough concentrations were within the currently recommended range of 10 to 20 mg/L. Although no consistent dosing recommendations were provided, all studies recommended close monitoring of trough concentrations. Based on limited clinical outcomes data, standardized recommendations for vancomycin dosing and monitoring in burn patients cannot be made. Higher total daily doses (40-70 mg/kg/day) and increased dosing frequency (every 6-12 hr in adults) may be necessary to achieve current target trough concentrations. Future research goals include prospective investigation of clinical outcomes related to initial doses, loading doses, monitoring peak and trough concentrations, and adverse effects. Further data on the effects of burn size, concomitant diseases, inhalation injury, and time since injury may improve the accuracy of vancomycin dosing in burn patients.


Assuntos
Queimaduras/tratamento farmacológico , Monitorização Fisiológica/métodos , Vancomicina/uso terapêutico , Infecção dos Ferimentos/tratamento farmacológico , Adulto , Fatores Etários , Queimaduras/diagnóstico , Criança , Estudos de Coortes , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Infusões Intravenosas , Escala de Gravidade do Ferimento , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Medição de Risco , Resultado do Tratamento , Infecção dos Ferimentos/microbiologia
17.
J Manag Care Spec Pharm ; 20(5): 467-76, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24761818

RESUMO

BACKGROUND: Literature has shown that chronic pain patients prescribed opioids are at an increased risk for experiencing drug-drug interactions as a result of polypharmacy. In addition, chronic, noncancer pain patients who experience drug-drug interactions have been shown to have greater health care utilization and costs. However, no study has focused on the health economics of major clinically significant drug-drug interactions associated with long-acting opioids. OBJECTIVES: To (a) estimate the prevalence of major drug-drug interactions among patients prescribed a long-acting opioid and (b) evaluate the potential impact of major drug-drug interactions on health care costs. METHODS: This study was a retrospective cohort analysis using claims data from the MarketScan Commercial Claims and Encounter Database between 2008 and 2010. Patients with at least 1 prescription for a long-acting opioid for ≥ 30 days were placed into cohorts according to the expected clinical impact of the potential drug-drug interaction: major versus none. Propensity score matching was used to mitigate differences in baseline characteristics between the cohorts. Health care costs were based on payments for all covered health care services, which consisted of inpatient and outpatient medical, emergency department, and outpatient prescription costs. RESULTS: Among 57,752 chronic, noncancer pain patients who met all inclusion and exclusion criteria, 5.7% (3,302) were exposed to a potential major drug-drug interaction. The costs associated with a potential interaction versus no potential interaction were significantly more after baseline characteristics of the cohorts were normalized by propensity score matching. Monthly health care costs in the 90-day post-index period were significantly greater ($3,366 vs. $2,757, a $609 difference) in patients exposed to a potential drug-drug interaction of major clinical significance, compared with those not exposed to a drug-drug interaction. The higher health care costs were mainly driven by outpatient and inpatient medical costs. CONCLUSIONS: Exposure to potential drug-drug interactions may result in unnecessary and unintended health care costs. Physicians should be made aware of commonly administered cytochrome P450 (CYP450) metabolized drugs in the chronic pain patient and consider prescribing non-CYP450 metabolized opioid and nonopioid analgesics. Managed care's use of utilization management tools to avoid these exposures may reduce costs.


Assuntos
Analgésicos Opioides/efeitos adversos , Dor Crônica/tratamento farmacológico , Dor Crônica/economia , Interações Medicamentosas , Custos de Cuidados de Saúde , Programas de Assistência Gerenciada/economia , Analgésicos Opioides/economia , Analgésicos Opioides/farmacocinética , Biotransformação , Distribuição de Qui-Quadrado , Dor Crônica/diagnóstico , Dor Crônica/epidemiologia , Redução de Custos , Inibidores das Enzimas do Citocromo P-450/efeitos adversos , Sistema Enzimático do Citocromo P-450/metabolismo , Custos de Medicamentos , Humanos , Análise dos Mínimos Quadrados , Modelos Lineares , Análise Multivariada , Polimedicação , Prevalência , Pontuação de Propensão , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Estados Unidos/epidemiologia
18.
J Clin Pharmacol ; 54(1): 3-13, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24166743

RESUMO

The study of transporter-mediated drug-drug interactions (DDI) requires use of appropriate probes to reflect transporter function. Digoxin is often used as a probe in DDI studies involving P-glycoprotein (P-gp) and is recommended by FDA for this purpose, despite several lingering questions regarding suitability of digoxin as P-gp probe. This review aims to critically evaluate use of digoxin as a probe for P-gp-mediated clinical DDI studies, with focus on sensitivity and specificity of digoxin for P-gp. Although previous reviews have evaluated digoxin transport by P-gp, the purpose of the current review is to critically evaluate such literature in light of newly evolving literature suggesting digoxin transport by non-P-gp transporters.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Proteínas de Transporte/metabolismo , Digoxina , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Animais , Proteínas de Transporte/genética , Interações Medicamentosas , Interações Alimento-Droga , Humanos , Preparações Farmacêuticas/metabolismo
19.
PLoS One ; 8(9): e72540, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24023749

RESUMO

The northeastern United States is a predominately-forested region that, like most of the eastern U.S., has undergone a 400-year history of intense logging, land clearance for agriculture, and natural reforestation. This setting affords the opportunity to address a major ecological question: How similar are today's forests to those existing prior to European colonization? Working throughout a nine-state region spanning Maine to Pennsylvania, we assembled a comprehensive database of archival land-survey records describing the forests at the time of European colonization. We compared these records to modern forest inventory data and described: (1) the magnitude and attributes of forest compositional change, (2) the geography of change, and (3) the relationships between change and environmental factors and historical land use. We found that with few exceptions, notably the American chestnut, the same taxa that made up the pre-colonial forest still comprise the forest today, despite ample opportunities for species invasion and loss. Nonetheless, there have been dramatic shifts in the relative abundance of forest taxa. The magnitude of change is spatially clustered at local scales (<125 km) but exhibits little evidence of regional-scale gradients. Compositional change is most strongly associated with the historical extent of agricultural clearing. Throughout the region, there has been a broad ecological shift away from late successional taxa, such as beech and hemlock, in favor of early- and mid-successional taxa, such as red maple and poplar. Additionally, the modern forest composition is more homogeneous and less coupled to local climatic controls.


Assuntos
Árvores , Ecossistema , Geografia , New England
20.
Ecol Appl ; 21(7): 2425-44, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22073633

RESUMO

Land use and climate change have complex and interacting effects on naturally dynamic forest landscapes. To anticipate and adapt to these changes, it is necessary to understand their individual and aggregate impacts on forest growth and composition. We conducted a simulation experiment to evaluate regional forest change in Massachusetts, USA over the next 50 years (2010-2060). Our objective was to estimate, assuming a linear continuation of recent trends, the relative and interactive influence of continued growth and succession, climate change, forest conversion to developed uses, and timber harvest on live aboveground biomass (AGB) and tree species composition. We examined 20 years of land use records in relation to social and biophysical explanatory variables and used regression trees to create "probability-of-conversion" and "probability-of-harvest" zones. We incorporated this information into a spatially interactive forest landscape simulator to examine forest dynamics as they were affected by land use and climate change. We conducted simulations in a full-factorial design and found that continued forest growth and succession had the largest effect on AGB, increasing stores from 181.83 Tg to 309.56 Tg over 50 years. The increase varied from 49% to 112% depending on the ecoregion within the state. Compared to simulations with no climate or land use, forest conversion reduced gains in AGB by 23.18 Tg (or 18%) over 50 years. Timber harvests reduced gains in AGB by 5.23 Tg (4%). Climate change (temperature and precipitation) increased gains in AGB by 17.3 Tg (13.5%). Pinus strobus and Acer rubrum were ranked first and second, respectively, in terms of total AGB throughout all simulations. Climate change reinforced the dominance of those two species. Timber harvest reduced Quercus rubra from 10.8% to 9.4% of total AGB, but otherwise had little effect on composition. Forest conversion was generally indiscriminate in terms of species removal. Under the naive assumption that future land use patterns will resemble the recent past, we conclude that continued forest growth and recovery will be the dominant mechanism driving forest dynamics over the next 50 years, and that while climate change may enhance growth rates, this will be more than offset by land use, primarily forest conversion to developed uses.


Assuntos
Biomassa , Mudança Climática , Monitoramento Ambiental , Atividades Humanas , Árvores/fisiologia , Simulação por Computador , Conservação dos Recursos Naturais , Massachusetts , Modelos Teóricos
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