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INTRODUCCIÓN: Los premolares inferiores son conocidos por la naturaleza compleja de la configuración de sus conductos. Generalmente cuando presentan uno solo es estrecho y acintado. En la actualidad contamos con herramientas de diagnóstico más precisas como las Tomografías Computadas de Haz Cónico para evaluar la morfología de los conductos en los tres planos del espacio. OBJETIVO: Es estudiar la sección transversal de los conductos de premolares inferiores humanos, con un solo conducto radicular. MATERIAL Y MÉTODO: Fueron estudiados 120 premolares inferiores humanos extraídos. Los especímenes fueron estudiados por medio de CBCT, con un tomógrafo Carestream 8200. Del total de la muestra, se seleccionaron a través de las CBCT, sólo los premolares con un conducto. Los mismos fueron analizados en cortes perpendiculares al eje largo del diente (axiales) En cada pieza dentaria se midió el diámetro en sentido bucolingual y mesiodistal del conducto (expresado en milímetros) en los tres tercios: cervical, medio y apical. Posteriormente, se analizó la morfología del conducto en los cortes axiales, en los tres tercios antes mencionados, clasificándolos en: circulares, ovales, ovalesalargados y acintados. Las variables cuantitativas fueron representadas en tablas mediante promedio y desvío, mientras que las cualitativas con frecuencias y porcentajes. Se realizaron pruebas de Friedman y prueba de uniformidad chi cuadrado. Se utilizaron los soft RMedic e Infostat. En todos los casos el nivel de significación fue del 5%. RESULTADOS: El 1,22% de los casos presentaron un conducto circular y 4,88 % ovalado en todo su recorrido. El 93,9% de la muestra presentó diferentes morfologías en los 3 tercios del conducto: LCC en 21.95%, seguida por ACC con un 20.73% y OCC con un 10,98%. Se observó un predominio de conductos circulares en el 84% en el tercio apical y 56% en el medio; ovalados en tercio medio en un 31,71% y aplanados en el tercio cervical en un 37.8%. El diámetro promedio del conducto circular a 3 mm del ápice fue de 0,55 mm2. En cervical el promedio de diámetro mayor fue de 2.58 mm en BL y 0.83 mm en MD y en tercio medio 1,29 mm en BL y 0.82 mm en MD. CONCLUSIONES: Los premolares inferiores con un solo conducto presentaron diferentes morfologías en los tres tercios del conducto. El predominio de la anatomía fue Alargada o Aplanada en el tercio Cervical (37.80%) y predominio de Circulares en Medio (56.10%) y Apical (84.15%). Este tipo de conductos, que varían su morfología longitudinalmente, pueden ser un verdadero desafío para su instrumentación, irrigación y obturación.

Egg production and hatching success of the copepod Temora longicornis were measured in laboratory experiments and in the field (North Sea). In the laboratory, ingestion of four algal species (Thalassiosira weissflogii, Phaeocystis globosa, Isochrysis sp. and Dunaliella tertiolecta) was followed and the content of fatty acids in the algae was determined. The two food types (T. weissflogii and Isochrysis sp.) that provided the highest ingestion of carbon and long chain fatty acids also resulted in the highest egg production rate ([E.sub.r]) and hatching success (H%). In contrast, D. tertiolecta led to both low ingestion of carbon and long chain fatty acids, resulting in low reproductive success. There was a positive relationship between the amount of eicosapentaenoic fatty acid [20:5(n-3), EPA] ingested and [E.sub.r] and H%, and of the ratio between docosahexaenoic and eicosapentaenoic fatty acid [22:6(n-3)/20:5(n-3), DHA/EPA] in the ingested food and H%. In the field, chlorophyll a and specific fatty acids were measured and protists were enumerated, in order to investigate the link between these factors and the reproductive success of T. longicornis. Hatching time was found to be related to temperature and exceeded 120 h at 6[degrees]C. No relationship was found between chlorophyll a and reproductive success ([E.sub.r] or H%). [E.sub.r] correlated with the concentration of diatoms and ciliates, which were the dominating protists in early spring, indicating that food quantity was the limiting factor for [E.sub.r]. As in the laboratory experiments, H% was dependent on the fatty acid DHA and the ratio of DHA/EPA, which indicates that the quality of eggs (H%) is linked to the quality of food., Introduction Reproductive success of copepods depends on the number of eggs produced per day ([E.sub.r]) as well as their subsequent hatching success (H%). [E.sub.r] has been found to depend on [...]

The Leaf-Area-Index (LAI) is commonly used to characterize the plant canopy and is a fundamental indication of plant vitality and photosynthetic activity. The forest health status is not only vital for economical reasons, but also has a significant impact on global carbon sequestration. The LAI has a highly dynamic character among deciduous forests and is prone to significant seasonal fluctuations. Accurate continuous LAI measurements do provide valuable information on growth characteristics, but they require considerable measurement effort. In this study, we tested a novel method that would allow for continuous low-effort LAI parameterizations. For our study we used temperature measurements from 2011 to 2019 obtained at two meteorological stations: Station one is an open land station, station two is located inside a forest stand characterized by European beech (measurements were undertaken as part of the ICP Forests program), both are located in Klausen Leopoldsdorf (Austria). We chose the difference in daily maximum temperature between the two sites for our LAI parametrization (LAIpar) since the forest canopy has a significant impact on local radiation conditions. We were able to identify phenological events such as leaf unfolding, the end of leaf growth, and the beginning and end of defoliation by examining at the average course of the year for LAIpar. The resultant LAIpar values were compared to annual values derived from hemispheric photographs taken near the stand temperature sensor. For the years 2011–2017, we found a strong correlation of 0.93 between LAI measures and LAIpar, which dropped to 0.69 after adding the year 2018 and 0.32 after adding 2019. We further compared the phenological events obtained from LAIpar to phenological observations. The impact of forests on their site climate, according to our findings, can be utilized to identify phenological and growth characteristics. The proposed method, however, is not a replacement for conventional LAI measurements.

In Table 3, column 'Phaeocystis globosa' the value for 'Cells (ml-1 initial concentration' was wrong and consequently led to other miscalculated values. The corrected Table 3 is shown below. The [...]

Chronic wounds are of high socio-economic importance. Accurate and efficient treatment includes the use of outcomes measures in clinical care and in research. To date, consented standards for documentation of chronic wounds, agreements on interpretation of wound outcomes and harmonisation about standardised goal setting in wound treatment are lacking. Objective (1) To establish a national German consensus group for the definition of standards in outcomes measurement of chronic wounds, (2) to agree on recommendations for practice and research based on a continuous decision process, including implementation of the standards. Methods The national consensus group includes delegates from the German scientific medical societies involved in health care for chronic wounds, the national boards on nursing, and the chairs of regional wound networks. Moreover, the roof organisations of the German health insurances, the German ministry of health and further single wound experts were invited. The consensus work is based on a structured decision process. Results The consensus group consists of 58 representatives and co-representatives of 26 societies and organisations. Since 2012, in the regular bi-annual meetings a Delphi-based workflow has been followed starting with standards for documentation and outcomes measurement in patients with leg ulcers. Additionally, web-based decision processes are conducted and the results are presented for finalisation in the face-to-face meetings. The following application areas of particular interests were defined: clinical routine, health services research, clinical research, and health economics. In the meantime, 245 single decisions have been approved. Conclusions Based on a national joint process involving medical societies, nursing groups, German sickness funds and health politics, a continuous decision process on standards for outcomes measurement and interpretation could be established. The Delphi based decision processes showed high levels of participations, thus providing a valid and robust set of standards. First results are in process of approval by the societies. [ABSTRACT FROM AUTHOR]

Treatment with interferon (IFN)-β 1a has been associated with decreased disease activity in patients with multiple sclerosis (MS). In several biological systems, type I IFNs and retinoids have been demonstrated to have synergistic effects. In these studies, we measured blood and cerebrospinal fluid (CSF) retinol levels and naïve and memory T-helper cell subset percentages in samples from a group of patients with MS. We also examined retinol receptor expression in peripheral blood cells from MS patients with or without a history of prior treatment with IFN-β1a. The mean plasma retinol level for untreated relapsing–remitting (RR) MS patients was lower than for patients with noninflammatory neurological disease. Among IFN-β1a-treated RR patients, mean levels were slightly higher than for RR patients not on treatment. Lower plasma retinol levels among the MS patients studied were associated with higher CSF retinol index measurements – a measure that was calculated to correct for nonspecific leakage of retinol from blood into CSF. For the MS samples examined, there was a borderline statistically significant direct correlation between CSF retinol index measurements and CSF memory T-helper cell percentages. Examination of peripheral blood from untreated RR patients for retinoid receptor mRNA expression revealed the expression of the retinoic acid receptor (RAR)-α , RAR-γ, and retinoic X receptor (RXR)-α receptor subtypes. For RR patients on IFN-β1a therapy, expression of the same RAR subtypes was noted as well as expression of RXR-β and RXR-γ. These studies suggest an association between plasma retinol levels and clinical disease activity in patients with MS and that treatment with IFN-β1a may be associated with activation of specific retinoid receptor subtypes. [ABSTRACT FROM AUTHOR]

Looks at a study which examined the intensity of oxidative damage in patients which cystic fibrosis (CF). Description of antioxidant depletion and increased free radical production by inflammatory cells in the patients; Measurement of a series of CF patients; Methodology used to conduct the study; Results of the study.

In a light microscopic study of the macula of 104 human eyes obtained at necropsy of patients aged 3 to 96 we found: (1) Displacement of nuclei from the outer nuclear layer into the outer plexiform layer occurred in small numbers early in life and markedly increased after age 30. (2) Displacement of nuclei from the outer nuclear layer to the layer of rods and cones was rare in early life but increased considerably after age 40. (3) Displacement of nuclei is probably secondary to shrinkage of their attached fibres and is associated with aging. (4) Displaced nuclei apparently undergo changes in size, shape, and chromatin content and may go on to necrosis. (5) Twenty-four of the 104 eyes studied had an obvious reduction in the numbers of nuclei in the outer nuclear layer and their photoreceptors in the macular zone. All were in eyes from patients over age 40. No concomitant defect was found in the subjacent pigment epithelium, Bruch's membrane, or the choriocapillaris. The loss of nuclei of the outer nuclear layer appears to be a primary retinal disorder associated with aging. [ABSTRACT FROM PUBLISHER]

Microcysts of the iris pigment epithelium have been described in association with diabetes mellitus, systemic mucopolysaccharidoses. Menkes's syndrome, and in neonates. Our study covers 68 cases obtained at necropsy. We specifically examined the iris pigment epithelium for vacuolation. We found that microcysts are more widespread than previously thought. In our series 57.3% of the cases reviewed by the light microscope showed microcysts. Of interest was the relationship of malignant neoplasm to iris pigment epithelium microcyst: 69.4% of cases with malignancy showed microcyst, whereas only 30% of the cases without neoplasms showed microcysts. Patients treated with exogenous steroid also had a raised incidence of microcysts. [ABSTRACT FROM PUBLISHER]

A retrospective study of the histopathological features of retinitis pigmentosa was undertaken. A consistent finding in 10 out of 10 eyes from 6 patients with retinitis pigmentosa was the presence of a preretinal membrane. The frequency of this finding has not been noted previously. Preretinal gliosis may well be responsible for the production of the abnormal glinting fundus reflex seen at the posterior pole in retinitis pigmentosa. [ABSTRACT FROM PUBLISHER]

A patient is reported in whom the clinical observation of extension of the corneal endothelium and Descemet's membrane in association with rubeosis iridis was confirmed by histopathological examination. In a study of eyes which had been removed and demonstrated rubeosis iridis and secondary glaucoma in 16 additional eyes revealed extension of the corneal endothelium and Descemet's membrane on to the anterior iris surface. In all instances the transition occurred at the pseudoangle formed by the attachment of peripheral anterior synechiae. The suggestion is made that the fibrovascular membrane of rubeosis iridis is the stimulus which excites the extension of the endothelium on to the iris surface. The association between rubeosis iridis and extension of the corneal endothelium and Descemet's membrane on to the iris has not been previously appreciated. [ABSTRACT FROM PUBLISHER]

A retrospective study of 737 consecutive necropsies yielded 15 cases of drusen of the optic nerve head, an incidence of 20-4 cases per thousand. This represents the highest incidence yet reported. The histopathological features of drusen of the nerve head included elevation of the nerve head, compression of optic nerve fibres, partial optic atrophy, cytoid bodies, disc haemorrhages, juxtapapillary retinal scarring with haemosiderin deposition, calcification, and iron deposition within drusen. [ABSTRACT FROM PUBLISHER]

We describe an acute human immunodeficiency virus (HIV) infection in 16 homosexual men who presented with painful swallowing (odynophagia). Eleven men had a maculopapular rash and 3 had palatal ulcers. At esophagogastroduodenoscopy (endoscopy), multiple discrete esophageal ulcers measuring 0.3 to 1.5 cm in diameter were observed. Electron microscopy of biopsy specimens taken from the ulcer margins in 8 men revealed viral particles 120 to 160 nm in diameter whose morphologic characteristics were those of retroviruses. Human immunodeficiency virus seroconversion was documented in 15 men by Western blot analysis. In 3 men, HIV-1 was isolated from peripheral blood mononuclear cells, in 2 men HIV-1 was isolated from peripheral blood monocytes, and in 1 man HIV-1 was isolated from tissue taken from the margins of the esophageal ulcers. These observations extend our knowledge of the clinical spectrum of acute HIV infection syndromes and suggest that cells in the esophagus are a target for HIV-1 infection. [ABSTRACT FROM AUTHOR]

Decline in blood CD4+ lymphocytes during primary symptomatic infections with HIV is usually attributed to viral killing, and has not been considered in terms of altered lymphocyte migration and sequestration. We therefore sought to examine whether CD4+ cell loss from blood of macaques undergoing an acute primary SIV infection might be due to increased synthesis of cytokines, known to profoundly affect lymphocyte trafficking, rather than to direct lymphocyte destruction by virus. The findings indicate that rapid lymphocyte depletion following acute infection is not selective for CD4+ cells, correlates precisely with increased plasma IFN-gamma and tumor necrosis factor-alpha levels, and is reversible. CD4/CD8 ratios in lymph nodes with high viral burdens remain relatively unchanged despite lymphocyte loss from blood. Levels of cytokine mRNA measured in lymphoid organs reflect neither cytokine plasma levels nor their potential to induce sequestration. These results support a model of cytokine-induced lymphocyte extravasation to account for the acute HIV/SIV-induced CD4+ cell lymphopenia and raise questions regarding the extent to which altered lymphocyte migration plays a role in the gradual CD4+ cell depletion throughout infection. [ABSTRACT FROM AUTHOR]