Age effect on retina and optic disc normal values

Purpose: To investigate retinal thickness and optic disc parameters by the Retinal Thickness Analyzer (RTA) glaucoma program in older normal subjects and to determine any age effect. Methods: Subjects over 40 years of age without any prior history of eye diseases were recruited. Only subjects completely normal on clinical ophthalmologic examination and on visual field testing by Humphrey Field Analyzer (HFA) using the SITA 24-2 program were included. A total of 74 eyes from 74 subjects with even age distribution over the decades were enrolled and underwent topographic measurements of the posterior pole and of the optic disc by RTA. The `glaucoma full' program in software version 4.11B was applied. Results: Mean patient age was 59.9 +/- 10.3 years with a range from 40 to 80 years. The only parameter intraocular pressure (IOP) correlated with was retinal posterior pole asymmetry (r=0.27, p=0.02). IOP itself increased significantly with age (r=0.341, p=0.003). Mean defect and pattern standard deviation of the HFA did not correlate with any of the retinal or optic disc measurements. Increasing age correlated significantly with some of the morphologic measurements of the RTA: decreasing perifoveal minimum thickness (r=-0.258, p=0.026), increased cup-to-disc area ratio (r=0.302, p=0.016) and increased cup area (r=0.338 p=0.007). Conclusions: An age effect exists for some of the retina and optic disc measurements obtained by the RTA. Copyright (C) 2005 S. Karger AG, Basel

Bone growth during rapamycin therapy in young rats

<p>Abstract</p> <p>Background</p> <p>Rapamycin is an effective immunosuppressant widely used to maintain the renal allograft in pediatric patients. Linear growth may be adversely affected in young children since rapamycin has potent anti-proliferative and anti-angiogenic properties.</p> <p>Methods</p> <p>Weanling three week old rats were given rapamycin at 2.5 mg/kg daily by gavage for 2 or 4 weeks and compared to a Control group given equivalent amount of saline. Morphometric measurements and biochemical determinations for serum calcium, phosphate, iPTH, urea nitrogen, creatinine and insulin-growth factor I (IGF-I) were obtained. Histomorphometric analysis of the growth plate cartilage, in-situ hybridization experiments and immunohistochemical studies for various proteins were performed to evaluate for chondrocyte proliferation, chondrocyte differentiation and chondro/osteoclastic resorption.</p> <p>Results</p> <p>At the end of the 2 weeks, body and tibia length measurements were shorter after rapamycin therapy associated with an enlargement of the hypertrophic zone in the growth plate cartilage. There was a decrease in chondrocyte proliferation assessed by <it>histone-4 </it>and <it>mammalian target of rapamycin </it>(<it>mTOR</it>) expression. A reduction in <it>parathyroid hormone/parathyroid hormone related peptide (PTH/PTHrP) </it>and an increase in <it>Indian hedgehog </it>(<it>Ihh</it>) expression may explain in part, the increase number of hypertrophic chondrocytes. The number of TRAP positive multinucleated chondro/osteoclasts declined in the chondro-osseous junction with a decrease in the <it>receptor activator of nuclear factor kappa β ligand </it>(<it>RANKL</it>) and <it>vascular endothelial growth factor </it>(<it>VEGF</it>) expression. Although body and tibial length remained short after 4 weeks of rapamycin, changes in the expression of chondrocyte proliferation, chondrocyte differentiation and chondro/osteoclastic resorption which were significant after 2 weeks of rapamycin improved at the end of 4 weeks.</p> <p>Conclusion</p> <p>When given to young rats, 2 weeks of rapamycin significantly decreased endochondral bone growth. No catch-up growth was demonstrated at the end of 4 weeks, although markers of chondrocyte proliferation and differentiation improved. Clinical studies need to be done to evaluate these changes in growing children.</p

LEPRA LEPROMATOSA PENEAL EN PACIENTE CON ENFERMEDAD DE CHAGAS. REPORTE DE UN CASO

Se presenta el caso de un paciente masculino de 52 años con fimosis secundaria a una masa pseudotumoral prepucial. El paciente presentaba una historia de enfermedad de Hansen con afectación de piel, laringe y bronquios. Previa a la circuncisión, el examen físico revelaba, además de las alteraciones lepromatosas, un mega esófago secundario a estenosis en la porción distal. El análisis laboratorial mediante la técnica de ELISA dio positivo para Trypanosoma cruzi, patógeno responsable de la enfermedad de Chagas. Sólo pudimos encontrar un caso previo reportado de lepra lepromatosa con afectación prepucial. La coexistencia de lepra y miocardiopatía chagásica es inusual pero bien conocida por casos reportados en Brasil e India. Sin embargo, de acuerdo a nuestros conocimientos, éste es el primer caso reportado de una sociación entre lepra lepromatosa y mega esófago chagásico en un paciente con fimosis

Detección inmunohistoquímica del virus de Epstein-Barr en pacientes con linfoma

El virus de Epstein-Barr es un gammaherpes virus que infecta principalmente a linfocitos B permaneciendo en un estado de latencia en el interior del mismo, pudiendo también infectar a linfocitos T y células epiteliales. La persistencia de la infección viral inmortaliza a los linfocitos y favorece el desarrollo de procesos linfoproliferativos malignos como linfomas. Si bien se conoce que la relación entre la infección crónica del virus y el desarrollo de linfoma, varía de acuerdo al tipo histológico, se incrementa en pacientes inmunocomprometidos y de edad avanzada, la evidencia científica indica no sólo la importancia de este virus como agente infeccioso asociado con la etiología de esta neoplasia, sino también como un marcador asociado a respuesta refractaria y peor supervivencia. El objetivo de este estudio observacional descriptivo, fue detectar la presencia del Epstein-Barr virus por técnicas de inmunohistoquímica empleando anticuerpos monoclonales anti antígeno viral proteína latente de membrana en 86 pacientes con linfoma. La positividad para proteína en el total de pacientes con linfoma fue del 44%, correspondiendo el 20% a pacientes con linfoma de Hodgkin y el 24% a pacientes con linfoma no Hodgkin. La detección del virus en estas enfermedades, contribuye al manejo clínico de las mismas ya que el virus no sólo tiene un rol etiológico, sino además es un marcador pronóstico importante, incluso de interés terapéutico

Development of an in vitro periodontal biofilm model for assessing antimicrobial and host modulatory effects of bioactive molecules

Background: Inflammation within the oral cavity occurs due to dysregulation between microbial biofilms and the host response. Understanding how different oral hygiene products influence inflammatory properties is important for the development of new products. Therefore, creation of a robust host-pathogen biofilm platform capable of evaluating novel oral healthcare compounds is an attractive option. We therefore devised a multi-species biofilm co-culture model to evaluate the naturally derived polyphenol resveratrol (RSV) and gold standard chlorhexidine (CHX) with respect to anti-biofilm and anti-inflammatory properties.&lt;p&gt;&lt;/p&gt; Methods: An in vitro multi-species biofilm containing &lt;i&gt;S. mitis, F. nucleatum, P. Gingivalis&lt;/i&gt; and &lt;i&gt;A. Actinomycetemcomitans&lt;/i&gt; was created to represent a disease-associated biofilm and the oral epithelial cell in OKF6-TERT2. Cytotoxicity studies were performed using RSV and CHX. Multi-species biofilms were either treated with either molecule, or alternatively epithelial cells were treated with these prior to biofilm co-culture. Biofilm composition was evaluated and inflammatory responses quantified at a transcriptional and protein level.&lt;p&gt;&lt;/p&gt; Results: CHX was toxic to epithelial cells and multi-species biofilms at concentrations ranging from 0.01-0.2%. RSV did not effect multi-species biofilm composition, but was toxic to epithelial cells at concentrations greater than 0.01%. In co-culture, CHX-treated biofilms resulted in down regulation of the inflammatory chemokine IL-8 at both mRNA and protein level. RSV-treated epithelial cells in co-culture were down-regulated in the release of IL-8 protein, but not mRNA.&lt;p&gt;&lt;/p&gt; Conclusions: CHX possesses potent bactericidal properties, which may impact downstream inflammatory mediators. RSV does not appear to have bactericidal properties against multi-species biofilms, however it did appear to supress epithelial cells from releasing inflammatory mediators. This study demonstrates the potential to understand the mechanisms by which different oral hygiene products may influence gingival inflammation, thereby validating the use of a biofilm co-culture model.&lt;p&gt;&lt;/p&gt

Thickening of the pulmonary artery wall in acute intramural hematoma of the ascending aorta

BACKGROUND: The occurrence of pulmonary artery obstruction in the course of acute aortic dissection is an unusual complication. The mechanism implicated is the rupture of the outer layer of the aorta and the subsequent hemorrhage into the adventitia of the pulmonary artery that causes its wall thickening and, at times, produces extrinsic obstruction of the vessel. There are no reports of this complication in acute intramural hematoma. CASE PRESENTATION: An 87-year-old woman was admitted to the hospital in shock after having had severe chest pain followed by syncope. An urgent transesophageal echocardiogram revealed the presence of acute intramural hematoma, no evidence of aortic dissection, severe pericardial effusion with cardiac tamponade, and periaortic hematoma that involved the pulmonary artery generating circumferential wall thickening of its trunk and right branch with no evidence of flow obstruction. Urgent surgery was performed but the patient died in the operating room. The post mortem examination, in the operating room, confirmed that there was an extensive hematoma around the aorta and beneath the adventitial layer of the pulmonary artery, with no evidence of flow obstruction. CONCLUSION: This is the first time that this rare complication is reported in the scenario of acute intramural hematoma and with the transesophageal echocardiogram as the diagnostic tool

Quantum physics meets biology

Quantum physics and biology have long been regarded as unrelated disciplines, describing nature at the inanimate microlevel on the one hand and living species on the other hand. Over the last decades the life sciences have succeeded in providing ever more and refined explanations of macroscopic phenomena that were based on an improved understanding of molecular structures and mechanisms. Simultaneously, quantum physics, originally rooted in a world view of quantum coherences, entanglement and other non-classical effects, has been heading towards systems of increasing complexity. The present perspective article shall serve as a pedestrian guide to the growing interconnections between the two fields. We recapitulate the generic and sometimes unintuitive characteristics of quantum physics and point to a number of applications in the life sciences. We discuss our criteria for a future quantum biology, its current status, recent experimental progress and also the restrictions that nature imposes on bold extrapolations of quantum theory to macroscopic phenomena.Comment: 26 pages, 4 figures, Perspective article for the HFSP Journa

Male age is associated with extra-pair paternity, but not with extra-pair mating behaviour

Extra-pair paternity is the result of copulation between a female and a male other than her social partner. In socially monogamous birds, old males are most likely to sire extra-pair offspring. The male manipulation and female choice hypotheses predict that age-specific male mating behaviour could explain this old-over-young male advantage. These hypotheses have been difficult to test because copulations and the individuals involved are hard to observe. Here, we studied the mating behaviour and pairing contexts of captive house sparrows, Passer domesticus. Our set-up mimicked the complex social environment experienced by wild house sparrows. We found that middle-aged males, which would be considered old in natural populations, gained most extra-pair paternity. However, both, female solicitation behaviour and subsequent extra-pair matings were not associated with male age. Further, copulations were more likely when solicited by females than when initiated by males (i.e. unsolicited copulations). Male initiated within-pair copulations were more common than male initiated extra-pair copulations. To conclude, our results did not support either hypothesis regarding age-specific male mating behaviour. Instead, female choice, independent of male age, governed copulation success, especially in an extra-pair context. Post-copulatory mechanisms might determine why older males sire more extra-pair offspring