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2.
Clin Oral Implants Res ; 34 Suppl 26: 64-85, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37750524

ABSTRACT

PURPOSE: The aim of this review was to evaluate the survival rates of restorations utilizing titanium base abutments (TBA) for restoring single-unit implant prostheses. MATERIALS AND METHODS: This review was conducted following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. The focus question was: In patients who require the restoration of a single dental implant utilizing a titanium base abutment, what are the determining factors and outcomes relating to implant prosthesis prognosis and survival? A comprehensive search of databases (PubMed, EMBASE, and Cochrane Library) was conducted on 16 April 2023 and updated on 5 May 2023. Randomized clinical trials (RCT), retrospective studies and prospective studies, reporting on the use of TBA for single implant prostheses, were reviewed. A Cochrane collaboration risk of bias assessment analysis was performed for randomized clinical studies, and the Newcastle-Ottawa Scale tool was applied for non-randomized studies. A meta-analysis was performed on clinical trials reporting on survival rates of both TBA and other abutments. Other clinical studies, reporting on TBA only, were included for descriptive statistics. RESULTS: The search provided 1159 titles after duplicates were removed. Six RCTs were included to perform a meta-analysis and compare the survival of the TBA to other abutments [OR 0.74; 95% CI: 0.21-2.63, heterogeneity; I2 0%; p = .99]. Twenty-three prospective and retrospective studies fulfilled the criteria and were included in the meta-analysis after 12 months of function. A total of 857 single implant-supported prostheses fabricated with a TBA were included. TBA abutments have an estimate 98.6% survival rate after 1 year in function (95% CI: 97.9%-99.4%). The mean follow-up period was 31.2 ± 16.9 months. CONCLUSIONS: Single implant prosthesis restored with titanium base abutments showed favourable short-term survival rates.


Subject(s)
Dental Implants , Titanium , Humans , Databases, Factual
3.
Glob Chang Biol ; 29(15): 4279-4297, 2023 08.
Article in English | MEDLINE | ID: mdl-37100767

ABSTRACT

There are limited data for greenhouse gas (GHG) emissions from smallholder agricultural systems in tropical peatlands, with data for non-CO2 emissions from human-influenced tropical peatlands particularly scarce. The aim of this study was to quantify soil CH4 and N2 O fluxes from smallholder agricultural systems on tropical peatlands in Southeast Asia and assess their environmental controls. The study was carried out in four regions in Malaysia and Indonesia. CH4 and N2 O fluxes and environmental parameters were measured in cropland, oil palm plantation, tree plantation and forest. Annual CH4 emissions (in kg CH4 ha-1 year-1 ) were: 70.7 ± 29.5, 2.1 ± 1.2, 2.1 ± 0.6 and 6.2 ± 1.9 at the forest, tree plantation, oil palm and cropland land-use classes, respectively. Annual N2 O emissions (in kg N2 O ha-1 year-1 ) were: 6.5 ± 2.8, 3.2 ± 1.2, 21.9 ± 11.4 and 33.6 ± 7.3 in the same order as above, respectively. Annual CH4 emissions were strongly determined by water table depth (WTD) and increased exponentially when annual WTD was above -25 cm. In contrast, annual N2 O emissions were strongly correlated with mean total dissolved nitrogen (TDN) in soil water, following a sigmoidal relationship, up to an apparent threshold of 10 mg N L-1 beyond which TDN seemingly ceased to be limiting for N2 O production. The new emissions data for CH4 and N2 O presented here should help to develop more robust country level 'emission factors' for the quantification of national GHG inventory reporting. The impact of TDN on N2 O emissions suggests that soil nutrient status strongly impacts emissions, and therefore, policies which reduce N-fertilisation inputs might contribute to emissions mitigation from agricultural peat landscapes. However, the most important policy intervention for reducing emissions is one that reduces the conversion of peat swamp forest to agriculture on peatlands in the first place.


Subject(s)
Carbon Dioxide , Greenhouse Gases , Humans , Carbon Dioxide/analysis , Methane/analysis , Agriculture , Soil , Greenhouse Gases/analysis , Trees , Indonesia , Nitrogen , Nitrous Oxide/analysis
4.
Compend Contin Educ Dent ; 42(6): F1-F11, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34077670

ABSTRACT

Ten keys for successful esthetic-zone single immediate implants encapsulate in an evidence-based manner the treatment planning and replacement of single hopeless teeth in the maxillary anterior sextant. These include two treatment-planning, five surgical, and three prosthetic keys, which, collectively, aim to minimize soft- and hard-tissue complications for an optimal esthetic implant restoration. The Straightforward, Advanced, and Complex (SAC) classification is designed to aid clinicians in the treatment planning of dental implant cases. As per this classification, cases are stratified by the degree of surgical and restorative risk and complexity for both the surgical and prosthetic phases of treatment. A technique-sensitive and skill-demanding task, the replacement of multiple adjacent teeth in the esthetic zone poses significant challenges for clinicians and is considered a complex SAC procedure surgically and restoratively. This article presents a case report on the replacement of multiple adjacent teeth in the esthetic zone, demonstrating the use of 10 key principles to achieve an optimal esthetic outcome.


Subject(s)
Dental Implants, Single-Tooth , Dental Implants , Dental Implantation, Endosseous , Esthetics, Dental , Humans , Maxilla/surgery
5.
Article in English | MEDLINE | ID: mdl-36168495

ABSTRACT

Objective: The National Healthcare Safety Network (NHSN) Antibiotic Resistance (AR) Option is a valuable tool that can be used by acute-care hospitals to track and report antibiotic resistance rate data. Selective and cascading reporting results in suppressed antibiotic susceptibility results and has the potential to adversely affect what data are submitted into the NHSN AR Option. We describe the effects of antibiotic suppression on NHSN AR Option data. Methods: NHSN AR Option data were collected from 14 hospitals reporting into an existing NHSN user group from January 1, 2017, to December 31, 2018, and linked to commercial automated antimicrobial susceptibility testing instruments (cASTI) that were submitted as part of unrelated Tennessee Emerging Infections Program surveillance projects. A susceptibility result was defined as suppressed if the result was not found in the NHSN AR Option data but was reported in the cASTI data. Susceptibility results found in both data sets were described as released. Proportions of suppressed and released results were compared using the Pearson χ2 and Fisher exact tests. Results: In total, 852 matched isolates with 3,859 unique susceptibilities were available for analysis. At least 1 suppressed antibiotic susceptibility result was available for 726 (85.2%) of the isolates. Of the 3,859 susceptibility results, 1,936 (50.2%) suppressed antibiotic susceptibility results were not reported into the NHSN AR option when compared to the cASTI data. Conclusion: The effect of antibiotic suppression described in this article has significant implications for the ability of the NHSN AR Option to accurately reflect antibiotic resistance rates.

6.
J Chem Phys ; 152(13): 134705, 2020 Apr 07.
Article in English | MEDLINE | ID: mdl-32268741

ABSTRACT

The oxidation of glycerol under alkaline conditions in the presence of a heterogeneous catalyst can be tailored to the formation of lactic acid, an important commodity chemical. Despite recent advances in this area, the mechanism for its formation is still a subject of contention. In this study, we use a model 1 wt. % AuPt/TiO2 catalyst to probe this mechanism by conducting a series of isotopic labeling experiments with 1,3-13C glycerol. Optimization of the reaction conditions was first conducted to ensure high selectivity to lactic acid in the isotopic labeling experiments. Selectivity to lactic acid increased with temperature and concentration of NaOH, but increasing the O2 pressure appeared to influence only the rate of reaction. Using 1,3-13C glycerol, we demonstrate that conversion of pyruvaldehyde to lactic acid proceeds via a base-promoted 1,2-hydride shift. There was no evidence to suggest that this occurs via a 2,1-methide shift under the conditions used in this study.

7.
Infect Control Hosp Epidemiol ; 41(3): 331-336, 2020 03.
Article in English | MEDLINE | ID: mdl-31937378

ABSTRACT

OBJECTIVE: To identify patient and provider characteristics associated with high-volume antibiotic prescribing for children in Tennessee, a state with high antibiotic utilization. DESIGN: Cross-sectional, retrospective analysis of pediatric (aged <20 years) outpatient antibiotic prescriptions in Tennessee using the 2016 IQVIA Xponent (formerly QuintilesIMS) database. METHODS: Patient and provider characteristics, including county of prescription fill, rural versus urban county classification, patient age group, provider type (nurse practitioner, physician assistant, physician, or dentist), physician specialty, and physician years of practice were analyzed. RESULTS: Tennessee providers wrote 1,940,011 pediatric outpatient antibiotic prescriptions yielding an antibiotic prescribing rate of 1,165 per 1,000 population, 50% higher than the national pediatric antibiotic prescribing rate. Mean antibiotic prescribing rates varied greatly by county (range, 39-2,482 prescriptions per 1,000 population). Physicians wrote the greatest number of antibiotic prescriptions (1,043,030 prescriptions, 54%) of which 56% were written by general pediatricians. Pediatricians graduating from medical school prior to 2000 were significantly more likely than those graduating after 2000 to be high antibiotic prescribers. Overall, 360 providers (1.7% of the 21,798 total providers in this dataset) were responsible for nearly 25% of both overall and broad-spectrum antibiotic prescriptions; 20% of these providers practiced in a single county. CONCLUSIONS: Fewer than 2% of providers account for 25% of pediatric antibiotic prescriptions. High antibiotic prescribing for children in Tennessee is associated with specific patient and provider characteristics that can be used to design stewardship interventions targeted to the highest prescribing providers in specific counties and specialties.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Drug Utilization/statistics & numerical data , Health Personnel/statistics & numerical data , Pediatrics/statistics & numerical data , Adolescent , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Infant , Male , Outpatients , Tennessee , Young Adult
8.
Infect Control Hosp Epidemiol ; 41(2): 135-142, 2020 02.
Article in English | MEDLINE | ID: mdl-31755401

ABSTRACT

OBJECTIVE: To identify prescriber characteristics that predict antibiotic high-prescribing behavior to inform statewide antimicrobial stewardship interventions. DESIGN: Retrospective analysis of 2016 IQVIA Xponent, formerly QuintilesIMS, outpatient retail pharmacy oral antibiotic prescriptions in Tennessee. SETTING: Statewide retail pharmacies filling outpatient antibiotic prescriptions. PARTICIPANTS: Prescribers who wrote at least 1 antibiotic prescription filled at a retail pharmacy in Tennessee in 2016. METHODS: Multivariable logistic regression, including prescriber gender, birth decade, specialty, and practice location, and patient gender and age group, to determine the association with high prescribing. RESULTS: In 2016, 7,949,816 outpatient oral antibiotic prescriptions were filled in Tennessee: 1,195 prescriptions per 1,000 total population. Moreover, 50% of Tennessee's outpatient oral antibiotic prescriptions were written by 9.3% of prescribers. Specific specialties and prescriber types were associated with high prescribing: urology (odds ratio [OR], 3.249; 95% confidence interval [CI], 3.208-3.289), nurse practitioners (OR, 2.675; 95% CI, 2.658-2.692), dermatologists (OR, 2.396; 95% CI, 2.365-2.428), physician assistants (OR, 2.382; 95% CI, 2.364-2.400), and pediatric physicians (OR, 2.340; 95% CI, 2.320-2.361). Prescribers born in the 1960s were most likely to be high prescribers (OR, 2.574; 95% CI, 2.532-2.618). Prescribers in rural areas were more likely than prescribers in all other practice locations to be high prescribers. High prescribers were more likely to prescribe broader-spectrum antibiotics (P < .001). CONCLUSIONS: Targeting high prescribers, independent of specialty, degree, practice location, age, or gender, may be the best strategy for implementing cost-conscious, effective outpatient antimicrobial stewardship interventions. More information about high prescribers, such as patient volumes, clinical scope, and specific barriers to intervention, is needed.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Drug Prescriptions/statistics & numerical data , Practice Patterns, Nurses'/statistics & numerical data , Practice Patterns, Physicians'/statistics & numerical data , Administration, Oral , Adolescent , Adult , Aged , Aged, 80 and over , Ambulatory Care/statistics & numerical data , Antimicrobial Stewardship/organization & administration , Child , Child, Preschool , Drug Prescriptions/standards , Female , Humans , Infant , Infant, Newborn , Logistic Models , Male , Middle Aged , Multivariate Analysis , Outpatients , Physician Assistants/statistics & numerical data , Practice Patterns, Dentists'/statistics & numerical data , Professional Practice Location , Retrospective Studies , Tennessee , Young Adult
9.
Infect Dis Clin North Am ; 34(1): 145-160, 2020 03.
Article in English | MEDLINE | ID: mdl-31836328

ABSTRACT

Given the population-level implications of antibiotic resistance and the importance of antibiotic stewardship in containment and prevention of resistance, public health has a vested interest in strengthening antibiotic stewardship efforts. There are opportunities for public health collaboration at all levels including local health departments, state public health programs, and through federal public health entities. This article discusses existing public health stewardship activities, opportunities for collaboration between public health and key partners in antibiotic stewardship programs, the potential for improvement and expansion of current activities, and possible new modes of collaboration that could be pursued.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Antimicrobial Stewardship/standards , Public Health/standards , Anti-Bacterial Agents/adverse effects , Anti-Bacterial Agents/pharmacology , Centers for Disease Control and Prevention, U.S./standards , Drug Resistance, Microbial , Health Services/standards , Hospitals/standards , Humans , Intersectoral Collaboration , Leadership , Public Health Administration/standards , Quality Improvement/standards , United States
10.
Infect Control Hosp Epidemiol ; 40(7): 817-818, 2019 07.
Article in English | MEDLINE | ID: mdl-31172901

ABSTRACT

A survey of hospital antimicrobial stewardship programs was performed to validate core element achievement data from the National Healthcare Safety Network's (NHSN) Patient Safety Component Annual Survey. In total, 89% of hospitals met all 7 core elements, compared to only 68% according to the NHSN survey.


Subject(s)
Antimicrobial Stewardship/statistics & numerical data , Hospitals/statistics & numerical data , Centers for Disease Control and Prevention, U.S. , Health Care Surveys , Humans , Tennessee/epidemiology , United States
12.
Environ Sci Technol ; 52(11): 6291-6299, 2018 06 05.
Article in English | MEDLINE | ID: mdl-29738664

ABSTRACT

Forest disturbances affect ecosystem biogeochemistry, water quality, and carbon cycling. We analyzed water chemistry before, during, and after a dieback event at a headwater catchment in the Bohemian Forest (central Europe) together with an un-impacted reference catchment, focusing on drivers and responses of dissolved organic carbon (DOC) leaching. We analyzed data regarding carbon input to the forest floor via litter and throughfall, changes in soil moisture and composition, streamwater chemistry, discharge, and temperature. We observed three key points. (i) In the first 3 years following dieback, DOC production from dead biomass led to increased concentrations in soil, but DOC leaching did not increase due to chemical suppression of its solubility by elevated concentrations of protons and polyvalent cations and elevated microbial demand for DOC associated with high ammonium (NH4+) concentrations. (ii) DOC leaching remained low during the next 2 years because its availability in soils declined, which also left more NH4+ available for nitrifiers, increasing NO3- and proton production that further increased the chemical suppression of DOC mobility. (iii) After 5 years, DOC leaching started to increase as concentrations of NO3-, protons, and polyvalent cations started to decrease in soil water. Our data suggest that disturbance-induced changes in N cycling strongly influence DOC leaching via both chemical and biological mechanisms and that the magnitude of DOC leaching may vary over periods following disturbance. Our study adds insights as to why the impacts of forest disturbances are sometime observed at the local soil scale but not simultaneously on the larger catchment scale.


Subject(s)
Carbon , Trees , Ecosystem , Europe , Forests , Soil
14.
Int J STD AIDS ; 28(6): 626-628, 2017 May.
Article in English | MEDLINE | ID: mdl-27733708

ABSTRACT

Integrase strand transfer inhibitors (INSTIs) have become integral antiretroviral therapy (ART) agents for treating HIV infection. We report the case of a 44-year-old male with a history of hemophilia A who developed diabetes mellitus four months after switching from abacavir, lamivudine, and efavirenz to abacavir, lamivudine, and raltegravir. Hemoglobin A1C normalized without further need for exogenous insulin after raltegravir was switched back to efavirenz. In this case report, we will review a possible mechanism for INSTI-induced hyperglycemia and/or diabetes mellitus.


Subject(s)
Diabetes Mellitus/chemically induced , Diabetes Mellitus/pathology , HIV Infections/complications , HIV Infections/drug therapy , HIV Integrase Inhibitors/adverse effects , Adult , Dideoxynucleosides/administration & dosage , Dideoxynucleosides/adverse effects , Drug Combinations , Glycated Hemoglobin/analysis , HIV Integrase Inhibitors/administration & dosage , Humans , Lamivudine/administration & dosage , Lamivudine/adverse effects , Male , Raltegravir Potassium/administration & dosage , Raltegravir Potassium/adverse effects
15.
16.
Faraday Discuss ; 188: 427-50, 2016 07 04.
Article in English | MEDLINE | ID: mdl-27074316

ABSTRACT

Gold and gold alloys, in the form of supported nanoparticles, have been shown over the last three decades to be highly effective oxidation catalysts. Mixed metal oxide perovskites, with their high structural tolerance, are ideal for investigating how changes in the chemical composition of supports affect the catalysts' properties, while retaining similar surface areas, morphologies and metal co-ordinations. However, a significant disadvantage of using perovskites as supports is their high crystallinity and small surface area. We report the use of a supercritical carbon dioxide anti-solvent precipitation methodology to prepare large surface area lanthanum based perovskites, making the deposition of 1 wt% AuPt nanoparticles feasible. These catalysts were used for the selective oxidation of glycerol. By changing the elemental composition of the perovskite B site, we dramatically altered the reaction pathway between a sequential oxidation route to glyceric or tartronic acid and a dehydration reaction pathway to lactic acid. Selectivity profiles were correlated to reported oxygen adsorption capacities of the perovskite supports and also to changes in the AuPt nanoparticle morphologies. Extended time on line analysis using the best oxidation catalyst (AuPt/LaMnO3) produced an exceptionally high tartronic acid yield. LaMnO3 produced from alternative preparation methods was found to have lower activities, but gave comparable selectivity profiles to that produced using the supercritical carbon dioxide anti-solvent precipitation methodology.

17.
Sci Total Environ ; 560-561: 110-22, 2016 08 01.
Article in English | MEDLINE | ID: mdl-27096491

ABSTRACT

In boreal forest catchments, solute transfer to streams is controlled by hydrological and biogeochemical processes occurring in the riparian zone (RZ). However, RZs are spatially heterogeneous and information about solute chemistry is typically limited. This is problematic when making inferences about stream chemistry. Hypothetically, the strength of links between riparian and stream chemistry is time-scale dependent. Using a ten-year (2003-2012) dataset from a northern Swedish catchment, we evaluated the suitability of RZ data to infer stream dynamics at different time scales. We focus on the role of the RZ versus upslope soils in controlling sulfate (SO4(2)(-)) and dissolved organic carbon (DOC). A priori, declines in acid deposition and redox-mediated SO4(2)(-) pulses control sulfur (S) fluxes and pool dynamics, which in turn affect dissolved organic carbon (DOC). We found that the catchment is currently a net source of S, presumably due to release of the S pool accumulated during the acidification period. In both, RZ and stream, SO4(2-) concentrations are declining over time, whereas DOC is increasing. No temporal trends in SO4(2-) and DOC were observed in upslope mineral soils. SO4(2-) explained the variation of DOC in stream and RZ, but not in upslope mineral soil. Moreover, as SO4(2-) decreased with time, temporal variability of DOC increased. These observations indicate that: (1) SO4(2-) is still an important driver of DOC trends in boreal catchments and (2) RZ processes control stream SO4(2-) and subsequently DOC independently of upslope soils. These phenomena are likely occurring in many regions recovering from acidification. Because water flows through a heterogeneous mosaic of RZs before entering the stream, upscaling information from limited RZ data to the catchment level is problematic at short-time scales. However, for long-term trends and annual dynamics, the same data can provide reasonable representations of riparian processes and support meaningful inferences about stream chemistry.

18.
PLoS One ; 11(3): e0152466, 2016.
Article in English | MEDLINE | ID: mdl-27023200

ABSTRACT

Ecological and biogeochemical processes in lakes are strongly dependent upon water temperature. Long-term surface warming of many lakes is unequivocal, but little is known about the comparative magnitude of temperature variation at diel timescales, due to a lack of appropriately resolved data. Here we quantify the pattern and magnitude of diel temperature variability of surface waters using high-frequency data from 100 lakes. We show that the near-surface diel temperature range can be substantial in summer relative to long-term change and, for lakes smaller than 3 km2, increases sharply and predictably with decreasing lake area. Most small lakes included in this study experience average summer diel ranges in their near-surface temperatures of between 4 and 7°C. Large diel temperature fluctuations in the majority of lakes undoubtedly influence their structure, function and role in biogeochemical cycles, but the full implications remain largely unexplored.


Subject(s)
Lakes/chemistry , Temperature , Models, Statistical , Models, Theoretical , Time Factors , Water/chemistry
19.
Environ Sci Technol ; 48(22): 13280-8, 2014 Nov 18.
Article in English | MEDLINE | ID: mdl-25325669

ABSTRACT

In 1999 we used the MAGIC (Model of Acidification of Groundwater In Catchments) model to project acidification of acid-sensitive European surface waters in the year 2010, given implementation of the Gothenburg Protocol to the Convention on Long-Range Transboundary Air Pollution (LRTAP). A total of 202 sites in 10 regions in Europe were studied. These forecasts can now be compared with measurements for the year 2010, to give a "ground truth" evaluation of the model. The prerequisite for this test is that the actual sulfur and nitrogen deposition decreased from 1995 to 2010 by the same amount as that used to drive the model forecasts; this was largely the case for sulfur, but less so for nitrogen, and the simulated surface water [NO3(-)] reflected this difference. For most of the sites, predicted surface water recovery from acidification for the year 2010 is very close to the actual recovery observed from measured data, as recovery is predominantly driven by reductions in sulfur deposition. Overall these results show that MAGIC successfully predicts future water chemistry given known changes in acid deposition.


Subject(s)
Acids/chemistry , Groundwater/chemistry , Models, Theoretical , Water Pollutants, Chemical/analysis , Computer Simulation , Environmental Monitoring/methods , Europe , Forecasting , Geography
20.
Environ Pollut ; 155(2): 201-7, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18207619

ABSTRACT

Increased plant productivity due to nitrogen pollution increases the strength of the global carbon sink, but is implicated in plant diversity loss. However, modelling and experimental studies have suggested that these effects are constrained by availability of other nutrients. In a survey of element concentrations in Calluna vulgaris across an N deposition gradient in the UK, shoot concentrations of N and more surprisingly phosphorus and potassium were positively correlated with N deposition; tissue N/P ratio even decreased with N deposition. Elevated P and K concentrations possibly resulted from improved acquisition due to additional enzyme production or mycorrhizal activity. Heather occurs on organic soils where nutrient limitations are likely due to availability constraints rather than small stocks. However, if this effect extends to other plant and soil types, effects of N deposition on C sinks and plant competition may not be as constrained by availability of other nutrients as previously proposed.


Subject(s)
Calluna/metabolism , Nitrogen/pharmacology , Phosphorus/analysis , Potassium/analysis , Soil Pollutants/pharmacology , Calluna/drug effects , Calluna/growth & development , Environmental Monitoring/methods , Phosphorus/metabolism , Plant Shoots/chemistry , Plant Shoots/drug effects , Plant Shoots/metabolism , Potassium/metabolism , Soil/analysis , United Kingdom
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