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BACKGROUND AND OBJECTIVES: Little is known about the role of radon in the epidemiology of stroke among women. We therefore examined the association between home radon exposure and risk of stroke among middle-aged and older women in the United States. METHODS: We conducted a prospective cohort study of postmenopausal women aged 50-79 years at baseline (1993-1998) in the Women's Health Initiative. We measured exposures as 2-day, indoor, lowest living-level average radon concentrations in picocuries per liter (pCi/L) as estimated in 1993 by the US Geological Survey and reviewed by the Association of American State Geologists under the Indoor Radon Abatement Act. We used Cox proportional hazards models to estimate risk of incident, neurologist-adjudicated stroke during follow-up through 2020 as a hazard ratio and 95% CI, adjusting for study design and participant demographic, social, behavioral, and clinical characteristics. RESULTS: Among 158,910 women without stroke at baseline (mean age 63.2 years; 83% white), 6,979 incident strokes were identified over follow-up (mean 13.4 years). Incidence rates were 333, 343, and 349 strokes per 100,000 woman-years at radon concentrations of <2, 2-4, and >4 pCi/L, respectively. Compared with women living at concentrations <2 pCi/L, those at 2-4 and >4 pCi/L had higher covariate-adjusted risks of incident stroke: hazard ratio (95% CI) 1.06 (0.99-1.13) and 1.14 (1.05-1.22). Using nonlinear spline functions to model radon, stroke risk was significantly elevated at concentrations ranging from 2 to 4 pCi/L (p = 0.0004), that is, below the United States Environmental Protection Agency Radon Action Level for mitigation (4 pCi/L). Associations were slightly stronger for ischemic (especially cardioembolic, small vessel occlusive, and large artery atherosclerotic) than hemorrhagic stroke, but otherwise robust in sensitivity analyses. DISCUSSION: Radon exposure is associated with moderately increased stroke risk among middle-aged and older women in the United States, suggesting that promulgation of a lower Radon Action Level may help reduce the domestic impact of cerebrovascular disease on public health.
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Accidente Cerebrovascular Hemorrágico , Radón , Accidente Cerebrovascular , Persona de Mediana Edad , Humanos , Femenino , Estados Unidos/epidemiología , Anciano , Estudios Prospectivos , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Radón/efectos adversos , Radón/análisis , Salud de la Mujer , Factores de Riesgo , IncidenciaRESUMEN
Plant macrofossils from packrat (Neotoma spp.) middens provide direct evidence of past vegetation changes in arid regions of North America. Here we describe the newest version (version 5.0) of the U.S. Geological Survey (USGS) North American Packrat Midden Database. The database contains published and contributed data from 3,331 midden samples collected in southwest Canada, the western United States, and northern Mexico, with samples ranging in age from 48 ka to the present. The database includes original midden-sample macrofossil counts and relative-abundance data along with a standardized relative-abundance scheme that makes it easier to compare macrofossil data across midden-sample sites. In addition to the midden-sample data, this version of the midden database includes calibrated radiocarbon (14C) ages for the midden samples and plant functional type (PFT) assignments for the midden taxa. We also provide World Wildlife Fund ecoregion assignments and climate and bioclimate data for each midden-sample site location. The data are provided in tabular (.xlsx), comma-separated values (.csv), and relational database (.mdb) files.
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Clima , Fósiles , Plantas , México , América del Norte , SigmodontinaeRESUMEN
BACKGROUND: In high-risk hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) early breast cancer (EBC), nanoparticle albumin-bound (nab)-paclitaxel showed promising efficacy versus solvent-based (sb)-paclitaxel in neoadjuvant trials; however, optimal patient and therapy selection remains a topic of ongoing research. Here, we investigate the potential of Oncotype DX® recurrence score (RS) and endocrine therapy (ET) response (low post-endocrine Ki67) for therapy selection. PATIENTS AND METHODS: Within the WSG-ADAPT trial (NCT01779206), high-risk HR+/HER2- EBC patients were randomized to (neo)adjuvant 4× sb-paclitaxel 175 mg/m2 q2w or 8× nab-paclitaxel 125 mg/m2 q1w, followed by 4× epirubicin + cyclophosphamide (90 mg + 600 mg) q2w; inclusion criteria: (i) cN0-1, RS 12-25, and post-ET Ki67 >10%; (ii) cN0-1 with RS >25. Patients with cN2-3 or (G3, baseline Ki67 ≥40%, and tumor size >1 cm) were allowed to be included without RS and/or ET response testing. Associations of key factors with pathological complete response (pCR) (primary) and survival (secondary) endpoints were analyzed using statistical mediation and moderation models. RESULTS: Eight hundred and sixty-four patients received neoadjuvant nab-paclitaxel (n= 437) or sb-paclitaxel (n = 427); nab-paclitaxel was superior for pCR (20.8% versus 12.9%, P = 0.002). pCR was higher for RS >25 versus RS ≤25 (16.0% versus 8.4%, P = 0.021) and for ET non-response versus ET response (15.1% versus 6.0%, P = 0.027); no factors were predictive for the relative efficacy of nab-paclitaxel versus sb-paclitaxel. Patients with pCR had longer distant disease-free survival [dDFS; hazard ratio 0.42, 95% confidence interval (CI) 0.20-0.91, P = 0.024]. Despite favorable prognostic association of RS >25 versus RS ≤25 with pCR (odds ratio 3.11, 95% CI 1.71-5.63, P ≤ 0.001), higher RS was unfavorably associated with dDFS (hazard ratio 1.03, 95% CI 1.01-1.05, P = 0.010). CONCLUSIONS: In high-risk HR+/HER2- EBC, neoadjuvant nab-paclitaxel q1w appears superior to sb-paclitaxel q2w regarding pCR. Combining RS and ET response assessment appears to select patients with highest pCR rates. The disadvantage of higher RS for dDFS is reduced in patients with pCR. These are the first results from a large neoadjuvant randomized trial supporting the use of RS to help select patients for neoadjuvant chemotherapy in high-risk HR+/HER2- EBC.
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Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Epirrubicina/uso terapéutico , Terapia Neoadyuvante/métodos , Solventes/uso terapéutico , Antígeno Ki-67 , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Paclitaxel/uso terapéutico , Albúminas/uso terapéutico , Ciclofosfamida/uso terapéutico , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismoRESUMEN
In the presence of a symptomatic epiretinal gliosis, pars plana vitrectomy with membrane peeling to remove the membrane is usually indicated in clinical practice. According to common clinical experience, almost no independent regression of such an epiretinal membrane and thus healing of the pathology alone exists. Therefore, the unusual case of bilateral independent regression of idiopathic epiretinal gliosis and formation of a lamellar macular hole in a 73-year-old male patient is described. Considerations of the possible mechanism are presented based on the existing literature. These include separation of inflammatory versus noninflammatory membranes, possible separation of individual layers depending on the status of the posterior vitreous limiting membrane and also the possible action of proteolytic systems in the posterior vitreous region. Finally, the question arises, whether patients have to be informed about this fact before possible surgery.
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Membrana Epirretinal , Perforaciones de la Retina , Anciano , Membrana Epirretinal/cirugía , Gliosis/complicaciones , Humanos , Masculino , Perforaciones de la Retina/cirugía , Vitrectomía/efectos adversos , Cuerpo Vítreo/patologíaRESUMEN
PURPOSE: Neovascular age-related macular degeneration (nAMD) often affects both eyes. This study compared real-life outcomes of the first affected eye (1st eye) and the last affected eye (2nd eye) after anti-vascular endothelial growth factor (anti-VEGF) treatment. MATERIAL AND METHODS: For this retrospective monocenter study 3217 eyes from 2793 patients with nAMD were identified, who received at least 3 anti-VEGF injections between 2006 and 2014 at the University Eye Hospital of Munich. Included in the study were patients with bilateral nAMD when the 1st and 2nd eyes were not previously treated and there was a strict adherence with continuous follow-up for at least 5 years. Corrected visual acuity, number of intravitreal injections and visits as well as central macular thickness were compared. RESULTS: A total of 72 eyes of 36 patients were included in this analysis. Before anti-VEGF therapy, the group of 2nd eyes showed significantly better mean visual acuity than the 1st eyes (pâ¯< 0.001). This difference in visual acuity between 1st and 2nd eyes was noted at all time points throughout the follow-up period (pâ¯< 0.05). The mean number of cumulative injections was higher in the group of 2nd eyes (pâ¯= 0.04) with a comparable number of visits between both groups. In more than half of all patients the 2nd eye became affected by nAMD within 12 months following treatment initiation of the 1st eye and the majority (83%) followed within 3 years. CONCLUSION: In unilateral nAMD, regular monitoring of the fellow eye is essential to avoid severe bilateral vision loss. Early diagnosis with rapid initiation of treatment can preserve visual acuity and quality of life.
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Calidad de Vida , Degeneración Macular Húmeda , Inhibidores de la Angiogénesis , Estudios de Seguimiento , Humanos , Inyecciones Intravítreas , Ranibizumab , Estudios Retrospectivos , Resultado del Tratamiento , Factor A de Crecimiento Endotelial Vascular , Degeneración Macular Húmeda/diagnóstico , Degeneración Macular Húmeda/tratamiento farmacológicoRESUMEN
The STOP-Bang questionnaire is an established clinical screening tool to identify the risk of having mild, moderate or severe obstructive sleep apnoea using eight variables. It is unclear whether all eight variables contribute equally to the risk of clinically significant obstructive sleep apnoea. We analysed each variable for its contribution to detecting obstructive sleep apnoea; based on the results, we investigated whether the STOP-Bang questionnaire could be abbreviated to identify patients at high risk for severe obstructive sleep apnoea. We recruited patients with suspected obstructive sleep apnoea who were referred for overnight polysomnography. We used multivariable logistic regression to investigate the association of STOP-Bang parameters with severe obstructive sleep apnoea based on clinical and polysomnography data. Regression estimates were used to select variables to create the novel B-APNEIC score. We constructed receiver operating characteristic curves for the STOP-Bang questionnaire and B-APNEIC scores to identify patients with severe obstructive sleep apnoea and compared the areas under the curve using the DeLong method. Of the 275 patients enrolled, 32% (n = 88) had severe obstructive sleep apnoea. Logistic regression demonstrated that neck circumference (OR 2.20; 95%CI 1.10-4.40, p = 0.03) was the only variable independently associated with severe obstructive sleep apnoea. Observed apnoea during sleep, blood pressure and body mass index were the three next most closely trending predictors of severe obstructive sleep apnoea and were included along with neck circumference in the B-APNEIC score. Receiver operating curves demonstrated that the areas under the curve for STOP-Bang vs. B-APNEIC were comparable for identifying patients with severe obstructive sleep apnoea (OR 0.75; 95%CI 0.68-0.81 vs. OR 0.75; 95%CI 0.68-0.81: p = 0.99, respectively). Our results suggest that the B-APNEIC score is a simplified adaptation of the STOP-Bang questionnaire with equivalent effectiveness in identifying patients with severe obstructive sleep apnoea. Further studies are needed to validate and build on our findings.
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Gravedad del Paciente , Polisomnografía/normas , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/fisiopatología , Encuestas y Cuestionarios/normas , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de RiesgoRESUMEN
BACKGROUND: Biomarkers are characteristic biological measurable signs and objective parameters to detect the state of health. Besides functional and temporal factors, imaging biomarkers play an increasingly important role. In full-thickness and lamellar defects of the macula numerous imaging parameters have been described. This knowledge resulted in new classifications for both clinical pictures, which are based on important biomarkers of these clinical pictures and characteristic features of described subtypes. METHODS: Imaging biomarkers for full-thickness and lamellar macular defects are described with respect to the classification and their functional prognostic importance. The importance of these biomarkers is presented. RESULTS: The current classification of full-thickness and lamellar macular defects is based on structural biomarkers. Biomarkers are important for prognostic and therapeutic evaluation and they have an impact on the surgical strategy. There are various surgical strategies for treatment of full-thickness macular holes depending on the size of the foramen and other biomarkers. The inverted ILM flap technique improves the closure rate of large macular holes. In lamellar macular holes showing signs of progression an early surgical intervention results in a good anatomical and functional prognosis. CONCLUSION: Multimodal diagnostics provide important preoperative, intraoperative, and postoperative features for macular holes and lamellar macular holes, which are essential biomarkers for the exact classification, the therapeutic strategy and for assessment of the prognosis.
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Membrana Epirretinal , Perforaciones de la Retina , Biomarcadores , Membrana Epirretinal/cirugía , Humanos , Perforaciones de la Retina/cirugía , Estudios Retrospectivos , Tomografía de Coherencia Óptica , VitrectomíaRESUMEN
Using high-resolution imaging, such as optical coherence tomography (OCT), the different layers of the retina as well as the vitreoretinal interface and its alterations can be very clearly differentiated. This includes the morphological characteristics of tractive maculopathies, such as epiretinal gliosis and vitreomacular traction syndrome. Additionally, structural alterations of the various layers of the neurosensory retina as a result of traction due to these pathologies can be demarcated. The latter have been investigated in clinical trials and evaluated as OCT biomarkers with respect to their prognostic and predictive value. In this review we would like to present and discuss various OCT biomarkers in the context of epimacular membranes and vitreomacular traction syndrome.
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Enfermedades de la Retina , Tomografía de Coherencia Óptica , Biomarcadores , Humanos , Retina , Enfermedades de la Retina/diagnóstico por imagen , TracciónRESUMEN
Helmet CPAP (H-CPAP) has been recommended in many guidelines as a noninvasive respiratory support during COVID-19 pandemic in many countries around the world. It has the least amount of particle dispersion and air contamination among all noninvasive devices and may mitigate the ICU bed shortage during a COVID surge as well as a decreased need for intubation/mechanical ventilation. It can be attached to many oxygen delivery sources. The MaxVenturi setup is preferred as it allows for natural humidification, low noise burden, and easy transition to HFNC during breaks and it is the recommended transport set-up. The patients can safely be proned with the helmet. It can also be used to wean the patients from invasive mechanical ventilation. Our article reviews in depth the pathophysiology of COVID-19 ARDS, provides rationale of using H-CPAP, suggests a respiratory failure algorithm, guides through its setup and discusses the issues and concerns around using it.
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COVID-19/terapia , Presión de las Vías Aéreas Positiva Contínua/instrumentación , Ventilación no Invasiva/instrumentación , Insuficiencia Respiratoria/terapia , Desconexión del Ventilador/métodos , COVID-19/diagnóstico , COVID-19/fisiopatología , COVID-19/transmisión , Dispositivos de Protección de la Cabeza , Humanos , Ventilación no Invasiva/métodos , Terapia por Inhalación de Oxígeno/instrumentación , Terapia por Inhalación de Oxígeno/métodos , Insuficiencia Respiratoria/diagnóstico , Insuficiencia Respiratoria/enfermería , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificaciónRESUMEN
BACKGROUND: Surgery for catecholamine-producing tumours can be complicated by intraoperative and postoperative haemodynamic instability. Several perioperative management strategies have emerged but none has been evaluated in randomized trials. To assess this issue, contemporary perioperative management and outcome data from 21 centres were collected. METHODS: Twenty-one centres contributed outcome data from patients who had surgery for phaeochromocytoma and paraganglioma between 2000 and 2017. The data included the number of patients with and without α-receptor blockade, surgical and anaesthetic techniques, complications and perioperative mortality. RESULTS: Across all centres, data were reported on 1860 patients with phaeochromocytoma or paraganglioma, of whom 343 underwent surgery without α-receptor blockade. The majority of operations (78·9 per cent) were performed using minimally invasive techniques, including 16·1 per cent adrenal cortex-sparing procedures. The cardiovascular complication rate was 5·0 per cent overall: 5·9 per cent (90 of 1517) in patients with preoperative α-receptor blockade and 0·9 per cent (3 of 343) among patients without α-receptor blockade. The mortality rate was 0·5 per cent overall (9 of 1860): 0·5 per cent (8 of 517) in pretreated and 0·3 per cent (1 of 343) in non-pretreated patients. CONCLUSION: There is substantial variability in the perioperative management of catecholamine-producing tumours, yet the overall complication rate is low. Further studies are needed to better define the optimal management approach, and reappraisal of international perioperative guidelines appears desirable.
ANTECEDENTES: La cirugía de los tumores productores de catecolaminas puede complicarse por la inestabilidad hemodinámica intraoperatoria y postoperatoria. Se han propuesto distintas estrategias de manejo perioperatorio, pero ninguna ha sido evaluada en ensayos aleatorizados. Para evaluar este tema, se han recogido los datos de los resultados y del manejo perioperatorio contemporáneo de 21 centros. MÉTODOS: Veintiún centros aportaron datos de los resultados de los pacientes operados por feocromocitoma y paraganglioma entre 2000-2017. Los datos incluyeron el número de pacientes con y sin bloqueo del receptor α, las técnicas quirúrgicas y anestésicas, las complicaciones y la mortalidad perioperatoria. RESULTADOS: Los centros en su conjunto aportaron datos de 1.860 pacientes con feocromocitoma y paraganglioma, de los cuales 343 pacientes fueron intervenidos sin bloqueo del receptor α. La gran mayoría (79%) de las cirugías se realizaron utilizando técnicas mínimamente invasivas, incluido un 17% de procedimientos con preservación de la corteza suprarrenal. La tasa de complicaciones cardiovasculares fue de 5,0% en total; 5,9% (90/1517) en pacientes con bloqueo preoperatorio de los receptores α y 0,9% (3/343) en pacientes no pretratados. La mortalidad global fue del 0,5% (9/1860); 0,5% (8/1517) en pacientes pretratados y 0,3% (1/343) en pacientes no tratados previamente. CONCLUSIÓN: Existe una variabilidad sustancial en el manejo perioperatorio de los tumores productores de catecolaminas, aunque la tasa global de complicaciones es baja. Este estudio brinda la oportunidad para efectuar comparaciones sistemáticas entre estrategias de prácticas terapéuticas variables. Se necesitan más estudios para definir mejor el enfoque de manejo óptimo y parece conveniente volver a evaluar las guías internacionales perioperatorias.
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Neoplasias de las Glándulas Suprarrenales/cirugía , Paraganglioma/cirugía , Atención Perioperativa/métodos , Feocromocitoma/cirugía , Pautas de la Práctica en Medicina/estadística & datos numéricos , Adrenalectomía/métodos , Adrenalectomía/mortalidad , Antagonistas Adrenérgicos alfa/uso terapéutico , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Atención Perioperativa/mortalidad , Resultado del TratamientoRESUMEN
An optic disc pit is a rare congenital abnormality of the optic nerve, which in most cases presents as a unilateral finding. Clinically, a greyish oval excavation is seen, most commonly on the temporal side of the optic nerve disc. The optic disc pit alone normally does not lead to substantial symptoms or functional limitations; however, when a maculopathy with intraretinal and/or subretinal fluid and additional other morphological changes in the macula occur, this leads to a decrease in visual acuity. With spectral domain optical coherence tomography (SDOCT) it is possible to identify the various forms of expression, which show different natural courses. Especially the presence of subretinal fluid and defects in the outer retinal layers have a poor prognosis and have the highest risk for further deterioration. Spontaneous resolution can occur but is rare. Observation is recommended in the first step. In cases of progression or pronounced deterioration, surgical intervention is indicated. Many different techniques have been proposed but there is no gold standard at the moment. Most of the surgical approaches comprise pars plana vitrectomy with peeling of the internal limiting membrane (ILM) and gas endotamponade. Newer methods, such as the ILM flap technique also show good results. Generally, it is important to know that postoperative healing and resorption of the fluid often take a long time period of up to 1 year or even longer.
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Anomalías del Ojo , Disco Óptico , Enfermedades de la Retina , Endotaponamiento , Humanos , Tomografía de Coherencia Óptica , VitrectomíaRESUMEN
PURPOSE: In daily practice, vitreomacular traction (VMT) is described by the horizontal diameter of its attachment site implying a regular round shape of VMT. We investigated the deviation from this circular area of vitreous traction in patients with VMT. METHODS: A retrospective analysis of optical coherence tomography (OCT) scans was performed. The area of vitreomacular attachment was determined using six radial OCT scans (Ameasured). The assumed circular area of traction was calculated based on measuring the maximal horizontal diameter for comparison (Acircular). RESULTS: Thirty-seven eyes of 37 patients with pure VMT were included. Patients' mean age was 72.8 ± 8.2 years. Mean horizontal VMT diameter was 400.8 ± 230.5 µm (median 361 µm; range 44-991 µm). While there was no difference between mean areas of traction for Acircular and Ameasured (P = 0.93), the individual difference (|Acircular - Ameasured|) was 0.042 (± 0.044) mm2 in mean or relative 73.0% (± 135.8%). A difference of ≥ 30% of Ameasured to Acircular was found in 16 eyes (43.2%) and ≥ 100% in 7 eyes (18.9%), respectively. CONCLUSION: Vitreous attachment sites possess an irregular non-circular shape in a significant number of eyes with VMT. Consequently, the area of traction appears inaccurately described by its horizontal VMT diameter alone. As the area of traction is important for therapeutic recommendation, our results emphasize the need for a more precise description of the area of traction in eyes with VMT.
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Mácula Lútea/patología , Enfermedades de la Retina/patología , Tomografía de Coherencia Óptica/métodos , Cuerpo Vítreo/patología , Desprendimiento del Vítreo/patología , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estudios Retrospectivos , Índice de Severidad de la EnfermedadRESUMEN
Neonicotinoids are a key group of insecticides used to manage Diaphorina citri Kuwayama (Hemiptera: Liviidae), in Florida citrus. Diaphorina citri is the vector of Candidatus Liberibacter asiaticus, the presumed causal agent of huanglongbing, a worldwide disease of citrus. A two-season field study was conducted to evaluate the effect of tree size and application rate on the expression of thiamethoxam in young citrus following application to the soil. D. citri adult and nymph abundance was also correlated with thiamethoxam titer in leaves. Tree size and application rate each significantly affected thiamethoxam titer in leaf tissue. The highest mean thiamethoxam titer observed (33.39 ppm) in small trees (mean canopy volume = 0.08 m3) occurred after application of the high rate (0.74 g Platinum 75SG per tree) tested. There was a negative correlation between both nymph and adult abundance with increasing thiamethoxam titer in leaves. A concentration of 64.63 ppm thiamethoxam was required to reach a 1% probability of encountering a flush shoot with at least one adult D. citri, while 19.05 ppm was required for the same probability of encountering nymphs. The LC90 for the field population was 7.62 ppm thiamethoxam when administered through ingestion. Exposure to dosages as low as 7.62 ppm would likely result in sublethal exposure of some proportion of the population, which could exacerbate resistance development. Based on our results, subsequent work should investigate the use of neonicotinoids by foliar rather than soil application to maintain the chemical class in future insecticide management programs in Florida citrus.
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Citrus , Hemípteros , Insecticidas , Neonicotinoides , Nitrocompuestos , Oxazinas , Tiazoles , Animales , Citrus/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga , Hemípteros/crecimiento & desarrollo , Ninfa/crecimiento & desarrollo , Hojas de la Planta , Tiametoxam , Árboles/crecimiento & desarrolloRESUMEN
The main pathways for phosphorus flux from land to sea are particle-associated (erosion) and dissolved runoff (rivers, groundwater, and agricultural drainage systems). These pathways can act as diffused sources for aquatic systems and support primary production, therefore, counteracting the efforts aimed at reducing phosphorus input from point sources such as sewage treatment plants. Phosphorus supports primary production in the water column and can elevate phytoplankton and macrophyte growth. Coastal wetlands with emerged (Phragmites australis) and submerged (Stuckenia pectinata and Chara sp.) macrophytes can affect phosphorus fluxes in the land-water transitional zone. The macrophytes have the potential to act as a buffer for phosphorus run-off. The aim of this study was to determine the phosphorus stocks in the transitional land-sea zone of a cold temperate lagoon at the southern Baltic Sea. Phosphorus in macrophytes, water samples, and phytoplankton growth were analyzed along a gradient moving away from the wetland. The phosphorus stocks in the above ground biomass of the Phragmites plants were the highest at the end of August and with more than 8000mgPm-2 in the interior zone of the wetland, threefold the amount of P in Phragmites plant tissue at the wetland fringe. The submerged macrophytes stored only 300mgPm-2, close to the wetland. Concentrations of soluble reactive phosphorus in the water column were higher in the zones of emerged macrophytes than in the zones of submerged macrophytes and decreased along the land-sea transect. Phytoplankton could grow proximal to the wetland during all seasons, but not further away. This study indicates that macrophytes can act as phosphorus sinks. However, short-term releases of phosphate within the Phragmites wetland have the potential to lead to phytoplankton growth. Phytoplankton can use these nutrient pulses either immediately or later, and support high biomass and turbidity within the system.
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Fósforo/análisis , Fitoplancton/fisiología , Poaceae/fisiología , Humedales , Biomasa , AlemaniaRESUMEN
BACKGROUND: High-resolution spectral domain optical coherence tomography (SD-OCT) is the standard examination for assessment of lamellar macular holes (LMH). According to the current SD-OCT classification of LMHs, they are characterized by (1) an irregular foveal contour, (2) a defect in the inner fovea, and (3) a separation of inner retinal layers from outer retinal layers of the fovea leading to an intraretinal splitting with loss of retinal tissue. OBJECTIVE: The article aims to give an overview on the current knowledge of retinal imaging in LMH diagnostics and clinical course of disease. MATERIALS AND METHODS: This review is based on current literature and analyses of data from different case series from the Department of Ophthalmology, Ludwig-Maximilian University Munich, Germany. RESULTS: In eyes with LMH, a homogenous atypical, hyporeflective epiretinal tissue has been described in addition to conventional tractional epiretinal membranes (ERM). By SD-OCT, this named lamellar hole-associated epiretinal proliferation (LHEP) does not show common signs of traction and is characterized as a thick homogenous layer of moderately reflective material. LHEP has been demonstrated to be related to the occurrence of photoreceptor layer defects, enlargement of LMH diameter and poor visual acuity. CONCLUSION: The correlation of SD-OCT and en-face OCT can help to identify LMH subgroups and morphology progression early on. FAF enables detection of structural changes at a subclinical stage without visual deterioration. With regard to a high variability of intraretinal changes in LMHs and epimacular fibro-cellular proliferation, the current classification of LMH should be discussed and re-evaluated.
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Membrana Epirretinal , Perforaciones de la Retina , Proliferación Celular , Estudios de Seguimiento , Humanos , Perforaciones de la Retina/diagnóstico por imagen , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Agudeza VisualRESUMEN
BACKGROUND: Using high-resolution spectral domain optical coherence tomography (SD-OCT), morphologically different types of epiretinal tissue can be distinguished in lamellar macular holes (LMH) and macular pseudoholes (MPH). OBJECTIVE: This article presents the results of histopathological characterization and differentiation of epiretinal tissue in eyes with LMH and MPH, which are classified based on a morphological differentiation in SD-OCT. MATERIAL AND METHODS: This review is based on the currently available literature and own data analyses. Using SD-OCT, a differentiation into hyporeflective epiretinal tissue and contractile epiretinal membranes (ERM) was performed. For fluorescence and transmission electron microscopic analyses, epiretinal tissue harvested by pars plana vitrectomy and peeling of epiretinal tissue was processed. RESULTS: By SD-OCT hyporeflective tissue appears as a thick homogeneous layer of hypodense material located directly on the surface of the inner retina and has no visible signs of traction. Using immunocytochemistry, hyalocytes and glial cells showing no contractile activity are dominant; however, in contractile ERM in MPH, anti-alpha SMA-positive myofibroblasts are predominantly found representing the contractile element. CONCLUSION: The results of ultrastructual investigations demonstrate that morphological cell components of hyporeflective epiretinal tissue from LMH have less contractile properties than cells of contractile ERM. It can therefore be assumed that there are differences in the pathogenesis of epiretinal cell proliferation in LMH. Histopathological investigations support the hypothesis that hyporeflective epiretinal tissue represents modified material from the outer layer of the vitreous body.