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1.
Nature ; 621(7978): 318-323, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37612502

RESUMEN

The Amazon forest carbon sink is declining, mainly as a result of land-use and climate change1-4. Here we investigate how changes in law enforcement of environmental protection policies may have affected the Amazonian carbon balance between 2010 and 2018 compared with 2019 and 2020, based on atmospheric CO2 vertical profiles5,6, deforestation7 and fire data8, as well as infraction notices related to illegal deforestation9. We estimate that Amazonia carbon emissions increased from a mean of 0.24 ± 0.08 PgC year-1 in 2010-2018 to 0.44 ± 0.10 PgC year-1 in 2019 and 0.52 ± 0.10 PgC year-1 in 2020 (± uncertainty). The observed increases in deforestation were 82% and 77% (94% accuracy) and burned area were 14% and 42% in 2019 and 2020 compared with the 2010-2018 mean, respectively. We find that the numbers of notifications of infractions against flora decreased by 30% and 54% and fines paid by 74% and 89% in 2019 and 2020, respectively. Carbon losses during 2019-2020 were comparable with those of the record warm El Niño (2015-2016) without an extreme drought event. Statistical tests show that the observed differences between the 2010-2018 mean and 2019-2020 are unlikely to have arisen by chance. The changes in the carbon budget of Amazonia during 2019-2020 were mainly because of western Amazonia becoming a carbon source. Our results indicate that a decline in law enforcement led to increases in deforestation, biomass burning and forest degradation, which increased carbon emissions and enhanced drying and warming of the Amazon forests.


Asunto(s)
Dióxido de Carbono , Secuestro de Carbono , Conservación de los Recursos Naturales , Política Ambiental , Aplicación de la Ley , Bosque Lluvioso , Biomasa , Brasil , Dióxido de Carbono/análisis , Dióxido de Carbono/metabolismo , Política Ambiental/legislación & jurisprudencia , Atmósfera/química , Incendios Forestales/estadística & datos numéricos , Conservación de los Recursos Naturales/estadística & datos numéricos , El Niño Oscilación del Sur , Sequías/estadística & datos numéricos
2.
Nature ; 595(7867): 388-393, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34262208

RESUMEN

Amazonia hosts the Earth's largest tropical forests and has been shown to be an important carbon sink over recent decades1-3. This carbon sink seems to be in decline, however, as a result of factors such as deforestation and climate change1-3. Here we investigate Amazonia's carbon budget and the main drivers responsible for its change into a carbon source. We performed 590 aircraft vertical profiling measurements of lower-tropospheric concentrations of carbon dioxide and carbon monoxide at four sites in Amazonia from 2010 to 20184. We find that total carbon emissions are greater in eastern Amazonia than in the western part, mostly as a result of spatial differences in carbon-monoxide-derived fire emissions. Southeastern Amazonia, in particular, acts as a net carbon source (total carbon flux minus fire emissions) to the atmosphere. Over the past 40 years, eastern Amazonia has been subjected to more deforestation, warming and moisture stress than the western part, especially during the dry season, with the southeast experiencing the strongest trends5-9. We explore the effect of climate change and deforestation trends on carbon emissions at our study sites, and find that the intensification of the dry season and an increase in deforestation seem to promote ecosystem stress, increase in fire occurrence, and higher carbon emissions in the eastern Amazon. This is in line with recent studies that indicate an increase in tree mortality and a reduction in photosynthesis as a result of climatic changes across Amazonia1,10.


Asunto(s)
Ciclo del Carbono , Secuestro de Carbono , Cambio Climático/estadística & datos numéricos , Conservación de los Recursos Naturales/estadística & datos numéricos , Bosques , Atmósfera/química , Dióxido de Carbono/análisis , Monóxido de Carbono/análisis , Actividades Humanas , Fotosíntesis , Lluvia , Estaciones del Año , Temperatura
3.
Med Res Rev ; 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38530106

RESUMEN

As the world population ages, there will be an increasing need for effective therapies for aging-associated neurodegenerative disorders, which remain untreatable. Dementia due to Alzheimer's disease (AD) is one of the leading neurological diseases in the aging population. Current therapeutic approaches to treat this disorder are solely symptomatic, making the need for new molecular entities acting on the causes of the disease extremely urgent. One of the potential solutions is to use compounds that are already in the market. The structures have known pharmacokinetics, pharmacodynamics, toxicity profiles, and patient data available in several countries. Several drugs have been used successfully to treat diseases different from their original purposes, such as autoimmunity and peripheral inflammation. Herein, we divulge the repurposing of drugs in the area of neurodegenerative diseases, focusing on the therapeutic potential of antineoplastics to treat dementia due to AD and dementia. We briefly touch upon the shared pathological mechanism between AD and cancer and drug repurposing strategies, with a focus on artificial intelligence. Next, we bring out the current status of research on the development of drugs, provide supporting evidence from retrospective, clinical, and preclinical studies on antineoplastic use, and bring in new areas, such as repurposing drugs for the prion-like spreading of pathologies in treating AD.

4.
Artículo en Inglés | MEDLINE | ID: mdl-38460549

RESUMEN

OBJECTIVES: To determine characteristics associated with patient-reported treatment success in psoriatic arthritis (PsA). METHODS: Rheumatologist-diagnosed PsA patients fulfilling the CASPAR classification were recruited from a single center. PsA outcome measures included: 66/68 swollen/tender joint counts, Leeds/SPARCC dactylitis/enthesitis indices, psoriasis body surface area (BSA), and patient-reported outcomes (PROs) including PROMIS. The primary outcome was a patient-reported item: "Today, considering the level of control of your psoriatic arthritis and psoriasis, do you consider your treatment has been successful?" Descriptive and multivariate logistic regression analyses identified clinical predictors of patient-reported treatment success. Patient-reported reasons for lack of treatment success were explored. RESULTS: A total of 178 participants had a baseline visit. Mean (SD) CASPAR score was 3.7 (0.9), age 51.7 (13.5) years, and BMI 31.3 (7.2) kg/m2. Fifty-two percent were women, and 86.0% white. Treatment success was reported by 116/178(65%) patients in the analytic cohort. Among 76 patients who reported treatment failure, the most frequently selected reasons for lack of success were pain (n = 55, 72.4%), fatigue (n = 46, 60.5%), inflamed joints (n = 40, 52.6%), and stiffness (n = 40, 52.6%). Overall, 105 participants had complete data across variables in the logistic regression models. Patient-reported treatment success was independently associated with the 66-swollen/68-tender joint counts, psoriasis BSA, PROs (pain interference, physical function, fatigue), and TNF-inhibitor therapy, after controlling for BMI and demographics. CONCLUSION: Patient-reported treatment success in PsA may be achieved through improvement of inflammatory arthritis, psoriasis, pain, physical function, fatigue, and the use ofTNF-inhibitors. Patients reported treatment failure was most commonly due to symptoms of pain, fatigue and stiffness.

5.
Synapse ; 78(4): e22304, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38896000

RESUMEN

The goal of this report is to explore how K2P channels modulate axonal excitability by using the crayfish ventral superficial flexor preparation. This preparation allows for simultaneous recording of motor nerve extracellular action potentials (eAP) and intracellular excitatory junctional potential (EJP) from a muscle fiber. Previous pharmacological studies have demonstrated the presence of K2P-like channels in crayfish. Fluoxetine (50 µM) was used to block K2P channels in this study. The blocker caused a gradual decline, and eventually complete block, of motor axon action potentials. At an intermediate stage of the block, when the peak-to-peak amplitude of eAP decreased to ∼60%-80% of the control value, the amplitude of the initial positive component of eAP declined at a faster rate than that of the negative peak representing sodium influx. Furthermore, the second positive peak following this sodium influx, which corresponds to the after-hyperpolarizing phase of intracellularly recorded action potentials (iAP), became larger during the intermediate stage of eAP block. Finally, EJP recorded simultaneously with eAP showed no change in amplitude, but did show a significant increase in synaptic delay. These changes in eAP shape and EJP delay are interpreted as the consequence of depolarized resting membrane potential after K2P channel block. In addition to providing insights to possible functions of K2P channels in unmyelinated axons, results presented here also serve as an example of how changes in eAP shape contain information that can be used to infer alterations in intracellular events. This type of eAP-iAP cross-inference is valuable for gaining mechanistic insights here and may also be applicable to other model systems.


Asunto(s)
Potenciales de Acción , Astacoidea , Axones , Fluoxetina , Neuronas Motoras , Animales , Astacoidea/efectos de los fármacos , Astacoidea/fisiología , Fluoxetina/farmacología , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Neuronas Motoras/efectos de los fármacos , Neuronas Motoras/fisiología , Axones/efectos de los fármacos , Axones/fisiología
6.
Malar J ; 23(1): 169, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811947

RESUMEN

BACKGROUND: The primary vector control interventions in Zambia are long-lasting insecticidal nets and indoor residual spraying. Challenges with these interventions include insecticide resistance and the outdoor biting and resting behaviours of many Anopheles mosquitoes. Therefore, new vector control tools targeting additional mosquito behaviours are needed to interrupt transmission. Attractive targeted sugar bait (ATSB) stations, which exploit the sugar feeding behaviours of mosquitoes, may help in this role. This study evaluated the residual laboratory bioefficacy of Westham prototype ATSB® Sarabi v.1.2.1 Bait Station (Westham Ltd., Hod-Hasharon, Israel) in killing malaria vectors in Western Province, Zambia, during the first year of a large cluster randomized phase-III trial (Clinical Trials.gov Identifier: NCT04800055). METHODS: This was a repeat cross-sectional study conducted within three districts, Nkeyema, Kaoma, and Luampa, in Western Province, Zambia. The study was conducted in 12 intervention clusters among the 70 trial clusters (35 interventions, 35 controls) between December 2021 and June 2022. Twelve undamaged bait stations installed on the outer walls of households were collected monthly (one per cluster per month) for bioassays utilizing adult female and male Anopheles gambiae sensu stricto (Kisumu strain) mosquitoes from a laboratory colony. RESULTS: A total of 84 field-deployed ATSB stations were collected, and 71 ultimately met the study inclusion criteria for remaining in good condition. Field-deployed stations that remained in good condition (intact, non-depleted of bait, and free of dirt as well as mold) retained high levels of bioefficacy (mean induced mortality of 95.3% in males, 71.3% in females, 83.9% combined total) over seven months in the field but did induce lower mortality rates than non-deployed ATSB stations (mean induced mortality of 96.4% in males, 87.0% in females, 91.4% combined total). There was relatively little variation in corrected mortality rates between monthly rounds for those ATSB stations that had been deployed to the field. CONCLUSION: While field-deployed ATSB stations induced lower mortality rates than non-deployed ATSB stations, these stations nonetheless retained relatively high and stable levels of bioefficacy across the 7-month malaria transmission season. While overall mean mosquito mortality rates exceeded 80%, mean mortality rates for females were 24 percentage points lower than among males and these differences merit attention and further evaluation in future studies. The duration of deployment was not associated with lower bioefficacy. Westham prototype ATSB stations can still retain bioefficacy even after deployment in the field for 7 months, provided they do not meet predetermined criteria for replacement.


Asunto(s)
Anopheles , Control de Mosquitos , Mosquitos Vectores , Zambia , Animales , Control de Mosquitos/métodos , Anopheles/efectos de los fármacos , Anopheles/fisiología , Mosquitos Vectores/efectos de los fármacos , Mosquitos Vectores/fisiología , Femenino , Masculino , Estudios Transversales , Malaria/prevención & control , Malaria/transmisión , Estaciones del Año , Insecticidas/farmacología , Azúcares , Humanos , Conducta Alimentaria
7.
Malar J ; 23(1): 153, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762448

RESUMEN

BACKGROUND: The attractive targeted sugar bait (ATSB) is a novel malaria vector control tool designed to attract and kill mosquitoes using a sugar-based bait, laced with oral toxicant. Western Province, Zambia, was one of three countries selected for a series of phase III cluster randomized controlled trials of the Westham ATSB Sarabi version 1.2. The trial sites in Kenya, Mali, and Zambia were selected to represent a range of different ecologies and malaria transmission settings across sub-Saharan Africa. This case study describes the key characteristics of the ATSB Zambia trial site to allow for interpretation of the results relative to the Kenya and Mali sites. METHODS: This study site characterization incorporates data from the trial baseline epidemiological and mosquito sugar feeding surveys conducted in 2021, as well as relevant literature on the study area. RESULTS: CHARACTERIZATION OF THE TRIAL SITE: The trial site in Zambia was comprised of 70 trial-designed clusters in Kaoma, Nkeyema, and Luampa districts. Population settlements in the trial site were dispersed across a large geographic area with sparsely populated villages. The overall population density in the 70 study clusters was 65.7 people per square kilometre with a total site population of 122,023 people living in a geographic area that covered 1858 square kilometres. However, the study clusters were distributed over a total area of approximately 11,728 square kilometres. The region was tropical with intense and seasonal malaria transmission. An abundance of trees and other plants in the trial site were potential sources of sugar meals for malaria vectors. Fourteen Anopheles species were endemic in the site and Anopheles funestus was the dominant vector, likely accounting for around 95% of all Plasmodium falciparum malaria infections. Despite high coverage of indoor residual spraying and insecticide-treated nets, the baseline malaria prevalence during the peak malaria transmission season was 50% among people ages six months and older. CONCLUSION: Malaria transmission remains high in Western Province, Zambia, despite coverage with vector control tools. New strategies are needed to address the drivers of malaria transmission in this region and other malaria-endemic areas in sub-Saharan Africa.


Asunto(s)
Anopheles , Malaria , Control de Mosquitos , Mosquitos Vectores , Azúcares , Zambia , Control de Mosquitos/métodos , Control de Mosquitos/estadística & datos numéricos , Mosquitos Vectores/efectos de los fármacos , Animales , Anopheles/efectos de los fármacos , Anopheles/fisiología , Humanos , Malaria/prevención & control , Malaria/transmisión , Femenino , Insecticidas/farmacología
8.
Clin Exp Rheumatol ; 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38607687

RESUMEN

OBJECTIVES: Autoantibodies have been described in the post-infectious state, specifically after Lyme disease and COVID-19. We aimed to describe the prevalence and potential clinical utility of several commercially available autoantibodies after these infections. METHODS: Euroimmun panels (myositis, scleroderma and ANA5) were assayed using sera from patients with Lyme disease with return to health (RTH) (n=70), post-treatment Lyme disease (n=58), COVID-19 RTH (n=47) and post-acute symptoms of COVID-19 (n=22). The post-Lyme questionnaire of symptoms (PLQS) was used to determine symptom burden after Lyme disease. RESULTS: There was no statistically significant difference in autoantibody prevalence across the four groups (p=0.746). A total of 21 different antibodies were found in the Lyme cohorts and 8 different antibodies in the COVID-19 cohorts. The prevalence of scleroderma-associated antibodies was higher after Lyme disease than COVID-19 (12.5% vs. 2.9%, p=0.026). There was no statistically significant difference in symptom burden based on antibody status. CONCLUSIONS: Several autoantibodies were found after Borrelia burgdorferi and SARS-CoV2 infection, although the prevalence was similar in those with persistent symptoms and those who returned to health. While our data show no difference in autoantibody prevalence across the four post-infectious states, we do not imply that autoantibodies are irrelevant in this setting. Rather, this study highlights the need for novel antibody discovery in larger cohorts of well-defined patient populations.

10.
Graefes Arch Clin Exp Ophthalmol ; 262(3): 813-822, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37955702

RESUMEN

PURPOSE: The purpose of this study is to investigate test-retest reliability and agreement of the quantitative contrast sensitivity function test (qCSF) in the retina clinic. METHODS: A total of 121 right eyes of 121 patients were tested and consecutively re-tested with qCSF in the retina clinic. Outcomes included area under the logarithm of contrast sensitivity function curve (AULCSF), contrast acuity, and contrast sensitivity thresholds at 1-18 cycles per degree (cpd). Test-retest means were compared with paired t-test, variability was compared with the Brown-Forsythe test, and intraclass correlation coefficient (ICC) and Bland Altman plots evaluated reliability and agreement. RESULTS: Mean test-retest differences for all qCSF metrics ranged from 0.02 to 0.05 log units without statistically significant differences in variability. Standard deviations ranged from 0.08 to 0.14. Coefficients of repeatability ranged from 0.16 to 0.27 log units. ICC > 0.9 for all metrics except 1cpd (ICC = 0.84, all p < 0.001); AULCSF ICC = 0.971. CONCLUSION: qCSF-measured contrast sensitivity shows great test-retest repeatability and agreement in the retina clinic.


Asunto(s)
Sensibilidad de Contraste , Pruebas de Visión , Humanos , Reproducibilidad de los Resultados , Retina
11.
Graefes Arch Clin Exp Ophthalmol ; 262(4): 1111-1120, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37962666

RESUMEN

PURPOSE: To explore the association between widefield swept-source optical coherence tomography angiography (WF SS-OCTA) metrics, including nonperfusion area (NPA) and neovascularization (NV), and presence of neovascular glaucoma (NVG) in patients with proliferative diabetic retinopathy (PDR). METHODS: A prospective, cross-sectional study was conducted from November 2018 to February 2020. A total of 85 eyes of 60 PDR patients without NVG and 9 eyes of 8 PDR patients with NVG were included. Retinal ischemic parameters (NPA; ischemia index [NPA/total retinal area]) and NV features (NV number; NV area; NV vessel density) were evaluated. Foveal avascular zone (FAZ), macular thickness/volume, and choroidal thickness/volume were obtained using the Zeiss ARI Network. WF SS-OCTA retinal and choroidal metrics, systemic, and ocular parameters were screened using Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression for variable selection. Firth's bias-reduced logistic regression (outcome: presence of NVG) was subsequently used to identify parameters associated with NVG. RESULTS: After LASSO variable selection, 8 variables were significantly associated with the presence of NVG: DM duration (years), insulin (yes/no), best-corrected visual acuity (BCVA) (logMAR), IOP, ischemia index, skeletonized vessel density, macular thickness (inner inferior, outer temporal regions). Firth's bias-reduced logistic regression showed ischemia index (odds ratio [OR]=13.2, 95% confidence interval [CI]:5.3-30.7, P<0.001) and BCVA (OR=5.8, 95%CI:1.2-28.8, P<0.05) were associated with the presence of NVG. NV metrics, FAZ, and choroidal parameters were not related to NVG. CONCLUSIONS: Retinal ischemia but not NV was associated with the presence of NVG in patients with PDR using WF SS-OCTA. Larger, longitudinal studies are needed to validate imaging biomarkers associated with diabetic NVG.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Glaucoma Neovascular , Humanos , Retinopatía Diabética/complicaciones , Retinopatía Diabética/diagnóstico , Vasos Retinianos , Angiografía con Fluoresceína/métodos , Glaucoma Neovascular/diagnóstico , Glaucoma Neovascular/etiología , Tomografía de Coherencia Óptica/métodos , Estudios Transversales , Estudios Prospectivos , Isquemia , Neovascularización Patológica
12.
Graefes Arch Clin Exp Ophthalmol ; 262(3): 789-799, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37955700

RESUMEN

PURPOSE: To investigate associations between contrast sensitivity (CS) and vascular metrics on wide-field swept-source optical coherence tomography angiography (WF-SS-OCTA) in patients with retinal vein occlusion (RVO). METHODS: This prospectively recruited, cross-sectional observational study included RVO patients who underwent quantitative CS function (qCSF) testing and WF-SS-OCTA using 3 × 3, 6 × 6, and 12 × 12 mm angiograms on the same day. The study measured several qCSF outcomes and WF-SS-OCTA vascular metrics, including vessel density (VD), vessel skeletonized density (VSD), and foveal avascular zone (FAZ). The data were analyzed using multivariable regression analysis controlling for age and central subfield thickness (CST). RESULTS: A total of 43 RVO eyes of 43 patients and 30 fellow eyes were included. In RVO eyes, multiple vascular metrics were associated with CS outcomes but not visual acuity (VA). On 12 × 12 images, CS thresholds at 1 cpd, 1.5 cpd, and 3 cpd were significantly associated with VD and VSD, but VA was not. When comparing standardized regression coefficients, we found that vascular metrics had a larger effect size on CS than on VA. For instance, the standardized beta coefficient for FAZ area and CS at 6 cpd (ß* = - 0.46, p = 0.007) was larger than logMAR VA (ß* = 0.40, p = 0.011). CONCLUSION: Microvascular changes on WF-SS-OCTA in RVO had a larger effect size on CS than VA. This suggests CS may better reflect the microvascular changes of RVO compared to VA. qCSF-measured CS might be a valuable adjunct functional metric in evaluating RVO patients.


Asunto(s)
Mácula Lútea , Oclusión de la Vena Retiniana , Humanos , Sensibilidad de Contraste , Oclusión de la Vena Retiniana/diagnóstico , Tomografía de Coherencia Óptica , Estudios Transversales , Angiografía
13.
Graefes Arch Clin Exp Ophthalmol ; 262(7): 2111-2120, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38376563

RESUMEN

PURPOSE: To investigate the impact of anti-VEGF therapy on vascular metrics in eyes with macular edema secondary to central retinal vein occlusion (CRVO) using wider field swept-source OCT angiography (WF SS-OCTA). METHODS: We included 23 eyes with macular edema associated with non-ischemic CRVO from 22 patients treated with anti-VEGF therapy (median number of injections: 5 [2-9]). Changes in vessel density (VD), vessel skeletonized density (VSD), and foveal avascular zone (FAZ) parameters were measured using WF SS-OCTA. Visual acuity (VA) and central subfield thickness (CST) were also measured. RESULTS: Median CST decreased significantly from 369 µm (305-531) to 267 µm (243-300, p < 0.001). VD and VSD parameters in 12 × 12 mm images showed significant reductions. For instance, VSD in the whole retina decreased from a median of 13.37 (11.22-13.74) to 11.29 (9.36-12.97, p = 0.013). Additionally, a significant increase in FAZ circularity was found, suggesting improved microvascular integrity. Significant inverse correlations were found between the number of anti-VEGF injections and all VSD and VD parameters on the 12 × 12 mm images (p < 0.05). Notably, the reductions in VSD and VD on 12 × 12 mm angiograms in the deep capillary plexus (DCP) after each injection significantly correlated with increased logMAR VA (worse VA). CONCLUSION: Anti-VEGF therapy in CRVO patients not only mitigates macular edema but also alters the overall microvascular morphology and functionality as revealed by WF SS-OCTA.


Asunto(s)
Inhibidores de la Angiogénesis , Angiografía con Fluoresceína , Fondo de Ojo , Inyecciones Intravítreas , Ranibizumab , Oclusión de la Vena Retiniana , Vasos Retinianos , Tomografía de Coherencia Óptica , Factor A de Crecimiento Endotelial Vascular , Agudeza Visual , Humanos , Oclusión de la Vena Retiniana/tratamiento farmacológico , Oclusión de la Vena Retiniana/diagnóstico , Oclusión de la Vena Retiniana/fisiopatología , Tomografía de Coherencia Óptica/métodos , Angiografía con Fluoresceína/métodos , Inhibidores de la Angiogénesis/uso terapéutico , Inhibidores de la Angiogénesis/administración & dosificación , Masculino , Femenino , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Anciano , Ranibizumab/administración & dosificación , Persona de Mediana Edad , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/patología , Estudios Retrospectivos , Edema Macular/tratamiento farmacológico , Edema Macular/diagnóstico , Edema Macular/etiología , Edema Macular/fisiopatología , Estudios de Seguimiento , Bevacizumab/uso terapéutico , Bevacizumab/administración & dosificación , Receptores de Factores de Crecimiento Endotelial Vascular/uso terapéutico , Receptores de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Receptores de Factores de Crecimiento Endotelial Vascular/administración & dosificación , Anciano de 80 o más Años , Resultado del Tratamiento
14.
Proc Natl Acad Sci U S A ; 118(33)2021 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-34380737

RESUMEN

In the Arctic and Boreal region (ABR) where warming is especially pronounced, the increase of gross primary production (GPP) has been suggested as an important driver for the increase of the atmospheric CO2 seasonal cycle amplitude (SCA). However, the role of GPP relative to changes in ecosystem respiration (ER) remains unclear, largely due to our inability to quantify these gross fluxes on regional scales. Here, we use atmospheric carbonyl sulfide (COS) measurements to provide observation-based estimates of GPP over the North American ABR. Our annual GPP estimate is 3.6 (2.4 to 5.5) PgC · y-1 between 2009 and 2013, the uncertainty of which is smaller than the range of GPP estimated from terrestrial ecosystem models (1.5 to 9.8 PgC · y-1). Our COS-derived monthly GPP shows significant correlations in space and time with satellite-based GPP proxies, solar-induced chlorophyll fluorescence, and near-infrared reflectance of vegetation. Furthermore, the derived monthly GPP displays two different linear relationships with soil temperature in spring versus autumn, whereas the relationship between monthly ER and soil temperature is best described by a single quadratic relationship throughout the year. In spring to midsummer, when GPP is most strongly correlated with soil temperature, our results suggest the warming-induced increases of GPP likely exceeded the increases of ER over the past four decades. In autumn, however, increases of ER were likely greater than GPP due to light limitations on GPP, thereby enhancing autumn net carbon emissions. Both effects have likely contributed to the atmospheric CO2 SCA amplification observed in the ABR.

15.
Arthroscopy ; 40(7): 2042-2044, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38428697

RESUMEN

Management of patients with femoroacetabular impingement and moderate (Tönnis grade 2) osteoarthritis remains a debated topic. Outcomes show that such patients can benefit from hip arthroscopy, yet the improvement may not be as favorable as desired. Although certain factors, such as Tönnis grade 3 hip OA, older age, higher body mass index, bipolar cartilage defects, and joint space less than 2 mm, may influence surgeons to avoid arthroscopic treatment, the threshold for grade 2 OA is not as clear. Moreover, although radiographs may appear similar in patients with Tönnis grade 2, there may be a wide range of chondral damage seen arthroscopically. Thus, until higher-level studies are performed, it is the responsibility of the surgeon to delineate appropriate treatment strategies for individual patients in this category, and most of all, it is crucial for surgeons to set reasonable expectations for patients when considering hip arthroscopy. This highlights the importance of careful preoperative evaluation and patient education.


Asunto(s)
Artroscopía , Pinzamiento Femoroacetabular , Osteoartritis de la Cadera , Humanos , Pinzamiento Femoroacetabular/cirugía , Osteoartritis de la Cadera/cirugía
16.
BMC Bioinformatics ; 24(1): 313, 2023 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-37592230

RESUMEN

BACKGROUND: Antibiotic resistance is a major public health concern around the globe. As a result, researchers always look for new compounds to develop new antibiotic drugs for combating antibiotic-resistant bacteria. Bacteriocin becomes a promising antimicrobial agent to fight against antibiotic resistance, due to cases of both broad and narrow killing spectra. Sequence matching methods are widely used to identify bacteriocins by comparing them with the known bacteriocin sequences; however, these methods often fail to detect new bacteriocin sequences due to their high diversity. The ability to use a machine learning approach can help find new highly dissimilar bacteriocins for developing highly effective antibiotic drugs. The aim of this work is to develop a machine learning-based software tool called BaPreS (Bacteriocin Prediction Software) using an optimal set of features for detecting bacteriocin protein sequences with high accuracy. We extracted potential features from known bacteriocin and non-bacteriocin sequences by considering the physicochemical and structural properties of the protein sequences. Then we reduced the feature set using statistical justifications and recursive feature elimination technique. Finally, we built support vector machine (SVM) and random forest (RF) models using the selected features and utilized the best machine learning model to implement the software tool. RESULTS: We applied BaPreS to an established dataset and evaluated its prediction performance. Acquired results show that the software tool can achieve a prediction accuracy of 95.54% for testing protein sequences. This tool allows users to add new bacteriocin or non-bacteriocin sequences in the training dataset to further enhance the predictive power of the tool. We compared the prediction performance of the BaPreS with a popular sequence matching-based tool and a deep learning-based method, and our software tool outperformed both. CONCLUSIONS: BaPreS is a bacteriocin prediction tool that can be used to discover new highly dissimilar bacteriocins for developing highly effective antibiotic drugs. This software tool can be used with Windows, Linux and macOS operating systems. The open-source software package and its user manual are available at https://github.com/suraiya14/BaPreS .


Asunto(s)
Bacteriocinas , Antibacterianos/farmacología , Secuencia de Aminoácidos , Aprendizaje Automático , Programas Informáticos
17.
N Engl J Med ; 383(26): 2547-2556, 2020 12 24.
Artículo en Inglés | MEDLINE | ID: mdl-33369356

RESUMEN

BACKGROUND: Among women with epilepsy, studies regarding changes in seizure frequency during pregnancy have been limited by the lack of an appropriate nonpregnant comparator group to provide data on the natural course of seizure frequency in both groups. METHODS: In this prospective, observational, multicenter cohort study, we compared the frequency of seizures during pregnancy through the peripartum period (the first 6 weeks after birth) (epoch 1) with the frequency during the postpartum period (the following 7.5 months after pregnancy) (epoch 2). Nonpregnant women with epilepsy were enrolled as controls and had similar follow-up during an 18-month period. The primary outcome was the percentage of women who had a higher frequency of seizures that impaired awareness during epoch 1 than during epoch 2. We also compared changes in the doses of antiepileptic drugs that were administered in the two groups during the first 9 months of epoch 1. RESULTS: We enrolled 351 pregnant women and 109 controls with epilepsy. Among the 299 pregnant women and 93 controls who had a history of seizures that impaired awareness and who had available data for the two epochs, seizure frequency was higher during epoch 1 than during epoch 2 in 70 pregnant women (23%) and in 23 controls (25%) (odds ratio, 0.93; 95% confidence interval [CI], 0.54 to 1.60). During pregnancy, the dose of an antiepileptic drug was changed at least once in 74% of pregnant women and in 31% of controls (odds ratio, 6.36; 95% CI, 3.82 to 10.59). CONCLUSIONS: Among women with epilepsy, the percentage who had a higher incidence of seizures during pregnancy than during the postpartum period was similar to that in women who were not pregnant during the corresponding epochs. Changes in doses of antiepileptic drugs occurred more frequently in pregnant women than in nonpregnant women during similar time periods. (Funded by the National Institutes of Health; MONEAD ClinicalTrials.gov number, NCT01730170.).


Asunto(s)
Anticonvulsivantes/administración & dosificación , Epilepsia/tratamiento farmacológico , Complicaciones del Embarazo/tratamiento farmacológico , Convulsiones/prevención & control , Adulto , Femenino , Humanos , Incidencia , Periodo Posparto , Embarazo , Estudios Prospectivos , Convulsiones/epidemiología
18.
J Cardiovasc Electrophysiol ; 34(12): 2563-2572, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37787022

RESUMEN

BACKGROUND AND AIMS: Ablation of anteroseptal accessory pathways (AS-AP) is challenging, with lower success and more complications compared to other APs. AS-APs can be successfully ablated from the right atrium (RA) or the aortic valve's noncoronary cusp (NCC). We report two patients who required a hybrid ablation approach to achieve successful abolition of both anterograde and retrograde AS-AP conduction. METHODS AND RESULTS: A 21-year-old female with supraventricular tachycardia (SVT) and pre-excitation on electrocardiogram (ECG) underwent electrophysiology study (EPS) confirming an AS-AP with anterograde and retrograde conduction. Ablation in the NCC achieved immediate and persistent anterograde conduction block. Electrophysiological maneuvers showed persistent retrograde AP conduction and orthodromic reciprocating tachycardia (ORT) remained easily inducible. Additional ablation in the NCC did not eliminate retrograde conduction. Further ablation in the RA opposite the NCC at the site of earliest retrograde atrial activation during ORT restored sinus and eliminated retrograde AP conduction. A 52-year-old male with SVT and ECG with pre-excitation underwent EPS that confirmed an AS-AP with anterograde and retrograde conduction. Ablation was performed in the NCC resulting in immediate elimination of pre-excitation. Retrograde conduction was still present and confirmed by repeating electrophysiological maneuvers. Ablation was performed in the RA opposite the successful ablation site in the NCC, eliminating retrograde AP conduction. CONCLUSION: Two cases of AS-AP with anterograde and retrograde conduction and successful elimination of pathway conduction required a hybrid ablation approach from the NCC and RA. This approach may be helpful in other cases to improve success rates without using excessive ablation near the normal conduction system.


Asunto(s)
Ablación por Catéter , Taquicardia Paroxística , Taquicardia Reciprocante , Taquicardia Supraventricular , Tabique Interventricular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Fascículo Atrioventricular/cirugía , Trastorno del Sistema de Conducción Cardíaco , Ablación por Catéter/métodos , Electrocardiografía/métodos , Sistema de Conducción Cardíaco/cirugía , Taquicardia Supraventricular/diagnóstico , Taquicardia Supraventricular/cirugía
19.
J Neurol Neurosurg Psychiatry ; 94(11): 879-886, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37336643

RESUMEN

BACKGROUND: Magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) is a minimally invasive alternative to surgical resection for drug-resistant mesial temporal lobe epilepsy (mTLE). Reported rates of seizure freedom are variable and long-term durability is largely unproven. Anterior temporal lobectomy (ATL) remains an option for patients with MRgLITT treatment failure. However, the safety and efficacy of this staged strategy is unknown. METHODS: This multicentre, retrospective cohort study included 268 patients consecutively treated with mesial temporal MRgLITT at 11 centres between 2012 and 2018. Seizure outcomes and complications of MRgLITT and any subsequent surgery are reported. Predictive value of preoperative variables for seizure outcome was assessed. RESULTS: Engel I seizure freedom was achieved in 55.8% (149/267) at 1 year, 52.5% (126/240) at 2 years and 49.3% (132/268) at the last follow-up ≥1 year (median 47 months). Engel I or II outcomes were achieved in 74.2% (198/267) at 1 year, 75.0% (180/240) at 2 years and 66.0% (177/268) at the last follow-up. Preoperative focal to bilateral tonic-clonic seizures were independently associated with seizure recurrence. Among patients with seizure recurrence, 14/21 (66.7%) became seizure-free after subsequent ATL and 5/10 (50%) after repeat MRgLITT at last follow-up≥1 year. CONCLUSIONS: MRgLITT is a viable treatment with durable outcomes for patients with drug-resistant mTLE evaluated at a comprehensive epilepsy centre. Although seizure freedom rates were lower than reported with ATL, this series represents the early experience of each centre and a heterogeneous cohort. ATL remains a safe and effective treatment for well-selected patients who fail MRgLITT.


Asunto(s)
Epilepsia Refractaria , Epilepsia del Lóbulo Temporal , Epilepsia , Terapia por Láser , Humanos , Epilepsia del Lóbulo Temporal/cirugía , Estudios Retrospectivos , Convulsiones/cirugía , Epilepsia Refractaria/cirugía , Epilepsia/cirugía , Resultado del Tratamiento , Imagen por Resonancia Magnética , Rayos Láser
20.
Chemistry ; 29(36): e202300703, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37057902

RESUMEN

We describe the synthesis and biochemical and cellular profiling of five partially reduced or demethylated analogs of the marine macrolide (-)-zampanolide (ZMP). These analogs were derived from 13-desmethylene-(-)-zampanolide (DM-ZMP), which is an equally potent cancer cell growth inhibitor as ZMP. Key steps in the synthesis of all compounds were the formation of the dioxabicyclo[15.3.1]heneicosane core by an intramolecular HWE reaction (67-95 % yield) and a stereoselective aza-aldol reaction with an (S)-BINOL-derived sorbamide transfer complex, to establish the C(20) stereocenter (24-71 % yield). As the sole exception, for the 5-desmethyl macrocycle, ring-closure relied on macrolactonization; however, elaboration of the macrocyclization product into the corresponding zampanolide analog was unsuccessful. All modifications led to reduced cellular activity and lowered microtubule-binding affinity compared to DM-ZMP, albeit to a different extent. For compounds incorporating the reactive enone moiety of ZMP, IC50 values for cancer cell growth inhibition varied between 5 and 133 nM, compared to 1-12 nM for DM-ZMP. Reduction of the enone double bond led to a several hundred-fold loss in growth inhibition. The cellular potency of 2,3-dihydro-13-desmethylene zampanolide, as the most potent analog identified, remained within a ninefold range of that of DM-ZMP.


Asunto(s)
Macrólidos , Microtúbulos , Macrólidos/química , Relación Estructura-Actividad , Unión Proteica
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