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Purpose of the Review: Improved forest management is a promising avenue for climate change mitigation. However, we lack synthetic understanding of how different management actions impact aboveground carbon stocks, particularly at scales relevant for designing and implementing forest-based climate solutions. Here, we quantitatively assess and review the impacts of three common practices-application of inorganic NPK fertilizer, interplanting with N-fixing species, and thinning-on aboveground carbon stocks in plantation forests. Recent Findings: Site-level empirical studies show both positive and negative effects of inorganic fertilization, interplanting, and thinning on aboveground carbon stocks in plantation forests. Recent findings and the results of our analysis suggest that these effects are heavily moderated by factors such as species selection, precipitation, time since practice, soil moisture regime, and previous land use. Interplanting of N-fixing crops initially has no effect on carbon storage in main tree crops, but the effect becomes positive in older stands. Conversely, the application of NPK fertilizers increases aboveground carbon stocks, though the effect lessens with time. Moreover, increases in aboveground carbon stocks may be partially or completely offset by emissions from the application of inorganic fertilizer. Thinning results in a strong reduction of aboveground carbon stocks, though the effect lessens with time. Summary: Management practices tend to have strong directional effects on aboveground carbon stocks in plantation forests but are moderated by site-specific management, climatic, and edaphic factors. The effect sizes quantified in our meta-analysis can serve as benchmarks for the design and scoping of improved forest management projects as forest-based climate solutions. Overall, management actions can enhance the climate mitigation potential of plantation forests, if performed with sufficient attention to the nuances of local conditions. Supplementary Information: The online version contains supplementary material available at 10.1007/s40725-023-00182-5.
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PRCIS: We evaluated the factors that impacted time from glaucoma drainage implant (GDI) surgery to penetrating keratoplasty (PK) in eyes with previously clear corneas (ie, GDI-first sequence), and that specifically underwent a trabeculectomy before GDI surgery for intraocular pressure (IOP) control. PURPOSE: To describe through an event-triggered data collection method the clinical course and the long-term outcomes of 2 procedures that are commonly performed sequentially in complex clinical situations: GDI surgery and PK. The study investigates the clinical factors associated with the progression to PK and determines the GDI success rate and graft survival. METHODS: A single, tertiary-care center retrospective interventional cases series including patients with a sequential history of trabeculectomy, GDI surgery, and PK from 1999 to 2009. Outcome measures included IOP, visual acuity, graft failure, GDI failure, and time from GDI to PK. RESULTS: Of the eyes, 56% had primary open angle glaucoma. The time from the last trabeculectomy to GDI was 66.5 ± 66.7 months. Of the eyes, 84% received a Baerveldt GDI. Time from GDI to PK was 36.4 ± 28.4 months. IOP at the time of PK was between 5 mm Hg and 21 mm Hg in 90% of eyes. At the last follow-up, 48% of grafts were clear. At 5 years post-PK, 33% of corneal grafts remained clear, whereas 81% of tubes remained functional. CONCLUSIONS: Nearly half of the corneal grafts are clear at the last long-term follow-up. Graft failure occurs at a higher rate than tube failure suggesting that IOP control is only one and possibly not the most important factor in graft survival in eyes with prior glaucoma surgery.
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Implantes para Drenagem de Glaucoma , Glaucoma de Ângulo Aberto , Trabeculectomia , Humanos , Trabeculectomia/métodos , Pressão Intraocular , Ceratoplastia Penetrante , Estudos Retrospectivos , Seguimentos , Resultado do TratamentoRESUMO
Restoring forest cover is a key action for mitigating climate change. Although monoculture plantations dominate existing commitments to restore forest cover, we lack a synthetic view of how carbon accumulates in these systems. Here, we assemble a global database of 4756 field-plot measurements from monoculture plantations across all forested continents. With these data, we model carbon accumulation in aboveground live tree biomass and examine the biological, environmental, and human drivers that influence this growth. Our results identify four-fold variation in carbon accumulation rates across tree genera, plant functional types, and biomes, as well as the key mediators (e.g., genus of tree, endemism of species, prior land use) of variation in these rates. Our nonlinear growth models advance our understanding of carbon accumulation in forests relative to mean annual rates, particularly during the next few decades that are critical for mitigating climate change.
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Carbono , Florestas , Biomassa , Mudança Climática , Humanos , ÁrvoresRESUMO
PURPOSE: Gray crescents characterized by darkly pigmented regions on the optic nerve head could make assessment of cupping difficult by obscuring the true anatomic disc border. On slit-lamp examination, 2 morphologically distinct types of gray crescents at the curved disc boundary exist. The in vivo histologic characteristics differentiating these 2 types are described using spectral-domain (SD) OCT. METHODS: A prospective interventional case series in a single tertiary referral center. Sixteen eyes of 10 patients with gray crescents determined through clinical examination and fundus photography underwent cross-sectional optic nerve head and parapapillary imaging using high-resolution SD OCT. In vivo histology of gray crescents was characterized. RESULTS: In SD OCT images across the areas of gray crescent, type A gray crescents represent regions where the retinal pigment epithelium (RPE)-Bruch's membrane complex is absent and the dark underlying choroid is directly visible. In contrast, type B gray crescents represent regions of the retina where the RPE is clumped or thickened, typically appearing to be folded upon itself, revealing the embryonic continuity of the RPE and neuroretina. CONCLUSIONS: Shields type A and B gray crescents appear different clinically because histologically they represent differences in RPE. Type A grey crescents lack RPE, whereas type B crescents have thickened, folded RPE. Gray crescents can obscure the true disc border and result in pseudo-cupping of the optic nerve head. Identification of gray crescents is clinically important because failure to recognize pseudo-cupping can contribute to overdiagnosis of glaucoma.
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Glaucoma/diagnóstico , Disco Óptico/diagnóstico por imagem , Epitélio Pigmentado da Retina/patologia , Tomografia de Coerência Óptica/métodos , Corioide/patologia , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Estudos ProspectivosRESUMO
BACKGROUND: Monitoring adherence to national recommendations for annual chlamydia screening of female adolescents and young adult women is important for targeting quality improvement interventions to improve low screening rates. However, accurate measurement of rates may vary depending on the data source used to determine eligible sexually-active women. METHODS: The 2001-2004 NHANES data linked with Medicaid administrative data by respondent's unique identifier, the 2011-2012 NHANES data, and the 2004 and 2010 Medicaid data were used in this cross-sectional analysis. We defined self-reported sexual activity by self-reported sexual behaviors, claim-identified sexual activity by reproductive-related claims among women who had ≥ one healthcare claim, HEDIS-defined sexual activity by reproductive-related claims among women who were enrolled in Medicaid for ≥330 days and had ≥ one healthcare claim, and chlamydia tests by claims submitted in the 12 months prior to the survey interview. RESULTS: Of Medicaid women aged 18-25 years, 91.5% self-reported to be sexually-active. Of self-reported sexually-active women aged 18-25 years, 92.0% had ≥ one healthcare claim in the 12 months prior to the survey interview; of this subpopulation, only 58.8% were enrolled in Medicaid for ≥ 330 days in the 12 months prior to the survey interview; of this further subpopulation, 74.1% had healthcare claims identifying them as sexually-active in the 12 months prior to the survey interview. Of HEDIS-defined sexually-active women, 42.4% had chlamydia testing. CONCLUSION: Our study suggests that the number of sexually-active women aged 18-25 years used as the denominator in the chlamydia testing measure could be significantly different, depending upon the definition applied and the data used. Our data highlight the limited representativeness of Medicaid population in the current HEDIS measure on chlamydia testing when a high proportion of women who were enrolled in Medicaid for <330 days had been excluded from the measure. The interventions that can improve the proportion of women who were enrolled in Medicaid for ≥ 330 days among all young Medicaid women are needed not only for improving health care services, but also for measuring quality of healthcare.
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Infecções por Chlamydia/diagnóstico , Comportamento Sexual , Adolescente , Adulto , Centers for Medicare and Medicaid Services, U.S. , Estudos Transversais , Bases de Dados Factuais , Feminino , Humanos , Medicaid , Melhoria de Qualidade , Estados Unidos , Adulto JovemRESUMO
Buforin II (BF2) is a histone-derived antimicrobial peptide that causes cell death by translocating across membranes and interacting with nucleic acids. It contains one proline residue critical for its function. Previous research found that mutations replacing proline lead to decreased membrane translocation and antimicrobial activity as well as increased membrane permeabilization. This study further investigates the role of proline in BF2's antimicrobial mechanism by considering the effect of changing proline position on membrane translocation, membrane permeabilization, and antimicrobial activity. For this purpose, four mutants were made with proline substitution (P11A) or relocation (P11A/G7P, P11A/V12P, P11A/V15P). These mutations altered the amount of helical content. Although antimicrobial activity correlated with the α-helical content for the peptides containing proline, membrane translocation did not. This observation suggests that factors in BF2's bactericidal mechanism other than translocation must be altered by these mutations. To better explain these trends we also measured the nucleic acid binding and membrane permeabilization of the mutant peptides. A comparison of mutant and wild type BF2 activity revealed that BF2 relies principally on membrane translocation and nucleic acid binding for antimicrobial activity, although membrane permeabilization may play a secondary role for some BF2 variants. A better understanding of the role of proline in the BF2 antimicrobial mechanism will contribute to the further design and development of BF2 analogs. Moreover, since proline residues are prevalent among other antimicrobial peptides, this systematic characterization of BF2 provides general insights that can promote our understanding of other systems.
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Anti-Infecciosos/farmacologia , Proteínas/farmacologia , Sequência de Aminoácidos , Anti-Infecciosos/química , Permeabilidade da Membrana Celular/efeitos dos fármacos , Dicroísmo Circular , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Proteínas/química , Homologia de Sequência de AminoácidosRESUMO
OBJECTIVE: The objective of this study was to delineate the difference in the phenotype of diabetic retinopathy (DR) in Latinos versus Blacks using characteristics shown on fundus photography (FP) and fluorescein angiography (FA). RESEARCH DESIGN AND METHODS: This was a retrospective chart review of 203 adult Black and Latino diabetic patients from the King-Drew Medical Center eye clinic from January 1998 to March 2005. Systemic risk factors such as HbA(1c) and kidney function data were collected. FP and FA were analyzed and graded according to Early Treatment of Diabetic Retinopathy Study criteria. Statistical analysis was performed to determine whether a given lesion type was more characteristic of a particular racial group. RESULTS: Gender, age, median microalbumin-to-creatinine ratio (ACR), and average HbA(1c) values were not significantly different between the groups. The presence of clinically significant macular edema (CSME), focal or diffuse, was very high in both groups (44% in Latinos and 46% in Blacks), and the overall DR grades were similar. However, upon individual lesion analysis, the Latinos were noted to have more prevalent intraretinal hemorrhages involving a greater area of the retina (P=.046). CONCLUSIONS: Although Latinos and Blacks of comparable age and glycemic control are equally at risk for CSME and proliferative retinopathy, Latinos may be at greater risk for a specific phenotype of DR characterized by extravasation of intraretinal hemorrhages, which is associated with poor prognosis. Further prospective studies may uncover racial differences that may have implications for prognosis and therapy.
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População Negra/estatística & dados numéricos , Retinopatia Diabética/etnologia , Retinopatia Diabética/patologia , Angiofluoresceinografia , Hispânico ou Latino/estatística & dados numéricos , Idoso , Feminino , Humanos , Los Angeles/epidemiologia , Edema Macular/etnologia , Edema Macular/patologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Prevalência , Hemorragia Retiniana/etnologia , Hemorragia Retiniana/patologia , Estudos RetrospectivosRESUMO
Buforin II is a 21-amino acid polycationic antimicrobial peptide derived from a peptide originally isolated from the stomach tissue of the Asian toad Bufo bufo gargarizans. It is hypothesized to target a wide range of bacteria by translocating into cells without membrane permeabilization and binding to nucleic acids. Previous research found that the structure and membrane interactions of buforin II are related to lipid composition. In this study, we used molecular dynamics (MD) simulations along with lipid vesicle experiments to gain insight into how buforin II interacts differently with phosphatidylcholine (PC), phosphatidylglycerol (PG), and phosphatidylethanolamine (PE) lipids. Fluorescent spectroscopic measurements agreed with the previous assertion that buforin II does not interact with pure PC vesicles. Nonetheless, the reduced entry of the peptide into anionic PG membranes versus neutral PC membranes during simulations correlates with the experimentally observed reduction in BF2 translocation through pure PG membranes. Simulations showing membrane entry into PC also provide insight into how buforin II may initially penetrate cell membranes. Our MD simulations also allowed us to consider how neutral PE lipids affect the peptide differently than PC. In particular, the peptide had a more helical secondary structure in simulations with PE lipids. A change in structure was also apparent in circular dichroism measurements. PE also reduced membrane entry in simulations, which correlates with decreased translocation in the presence of PE observed in previous studies. Together, these results provide molecular-level insight into how lipid composition can affect buforin II structure and function and will be useful in efforts to design peptides with desired antimicrobial and cell-penetrating properties.