Copyright (C) 2008 John Wiley & Sons, Ltd “
“Bio-inspired de

Copyright (C) 2008 John Wiley & Sons, Ltd.”
“Bio-inspired designs can provide an answer to engineering problems such as swimming strategies

at the micron or nano-scale. Scientists are now designing artificial micro-swimmers that can mimic flagella-powered swimming of micro-organisms. In an application such as lab-on-a-chip in which micro-object manipulation in small flow geometries could be achieved by micro-swimmers, control of the swimming direction becomes an important aspect for retrieval and control of the micro-swimmer. A bio-inspired approach for swimming direction reversal (a flagellum bearing mastigonemes) can be used to design such a system and is being explored in the present work. We analyze the system using a computational framework in which the equations of solid mechanics and fluid dynamics are solved simultaneously. The fluid dynamics of Stokes flow is represented by a 2D Stokeslets approach while the solid mechanics behavior selleck kinase inhibitor is realized using Euler-Bernoulli beam elements. The working principle of a flagellum bearing mastigonemes can be broken up into two parts: (1) the contribution of the base flagellum and (2) the contribution

of mastigonemes, which act like cilia. These contributions are counteractive, and the net motion (velocity and direction) is a superposition of the two. In the present work, we also perform a dimensional analysis to understand the underlying physics associated with the system parameters such as the height of the

mastigonemes, the number of mastigonemes, the flagellar wave length and amplitude, the flagellum length, and mastigonemes rigidity. Our results provide fundamental physical insight GDC-0941 ic50 on the swimming of a flagellum with mastigonemes, and it provides guidelines for the design of artificial flagellar systems. (C) 2011 American Institute of Physics. [doi:10.1063/1.3608240]“
“Major spine surgery with multilevel instrumentation is followed by large amount of opioid consumption, significant pain and difficult mobilization in a population of predominantly chronic pain patients. This case-control study investigated if a standardized comprehensive pain and postoperative nausea and vomiting (PONV) treatment protocol would improve pain treatment in this population.

A GSK2879552 new regimen with acetaminophen, NSAIDs, gabapentin, S-ketamine, dexamethasone, ondansetron and epidural local anesthetic infusion or patient controlled analgesia with morphine, was introduced in a post-intervention group of 41 consecutive patients undergoing multilevel (median 10) instrumented spinal fusions and compared with 44 patients in a pre-intervention group.

Compared to patients in the pre-intervention group, patients treated according to the new protocol consumed less opioid on postoperative day (POD) 1 (P = 0.024) and 2 (P = 0.048), they were mobilized earlier from bed (P = 0.003) and ambulation was earlier both with and without a walking frame (P = 0.027 and P = 0.027, respectively).

In addition, many of the cells administered intrathecally survive

In addition, many of the cells administered intrathecally survived and a subset of them expressed mature neural-lineage markers, including the mature neuron marker NeuN and glial fibrillary acidic protein, typical of astrocytes. Animals that received hUCB-MSCs had significantly improved motor function and reduced ischemic damage when compared with untreated control animals. Regardless of the administration route, the group treated with 1 x 10(6)

hUCB-MSCs showed better neurological recovery, without significant differences between the two treatment groups. Importantly, intrathecal administration of 5 x 10(5) hUCB-MSCs significantly reduced ischemic damage, but not in the intravenously treated group. Furthermore, the cells administered selleck screening library intrathecally survived and

migrated into the ischemic area more extensively, and differentiated significantly into neurons and astrocytes.

Conclusions: Together, these results indicate that intrathecal administration of MSCs by LP may be useful and feasible for MSCs treatment of brain injuries, such as stroke, or neurodegenerative disorders.”
“Over the lifecycle of an orally inhaled product (OIP), multi-stage cascade impactor ACY-738 cost (CI) measurements are used for different purposes and to address different questions. Full-resolution CIs can provide important information during product development and are widely used but are time- and resource-intensive, highly variable, Nutlin-3 clinical trial and suboptimal for OIP quality control (QC) testing. By contrast, Efficient Data Analysis (EDA) combined with Abbreviated Impactor Measurement (AIM) systems pertinent either for QC and-possibly-for adult Human Respiratory Tract (pHRT) has been introduced for OIP performance assessment during and post-development. This article summarizes available evidence and discusses a strategy for using either abbreviated or full-resolution CI systems depending on the purpose

of the measurement, such that adequate, accurate, and efficient testing of aerodynamic particle size distribution (APSD) of OIPs can be achieved throughout the lifecycle of a product. Under these proposals, a comprehensive testing program should initially be conducted by full-resolution CI in OIP development to ascertain the product’s APSD. Subsequently, correlations should be established from the selected AIM CIs to the corresponding full-resolution system, ideally developing specifications common to both techniques. In the commercial phase, it should be possible to release product using AIM/EDA, keeping the full-resolution CI for investigations, change control, and trouble-shooting, thus optimizing resources for APSD characterization throughout the product lifecycle. If an in vitro-in vivo relationship is established and clinically relevant sizes are known, an AIM-pHRT could serve as a quick indicator that clinically relevant fractions have not changed and also, in the management of post-approval changes.

Conclusions and Clinical Relevance-Results indicated that neonata

Conclusions and Clinical Relevance-Results indicated that neonatal calves can have an important role in the transmission

of M bovis. Also, this report highlights the exigent need for unique individual identification of livestock, including neonatal animals, so that thorough epidemiological investigations of reportable (zoonotic or foreign animal) diseases can be conducted when necessary.”
“Mesh-augmented reconstructive surgery AZD7762 clinical trial for pelvic organ prolapse (POP) does not meet clinical expectations. A tissue-engineered fascia equivalent needs to be developed.

Human vaginal fibroblasts (HVFs) from 10 patients were characterized in vitro. Eligible HVFs and a biodegradable scaffold were used to fabricate a fascia equivalent, which was then transplanted in vivo.

The cultured HVFs were divided into high (n = 6) or low (n = 4) collagen I/III ratio groups. Cells of the high-ratio group exhibited significantly higher proliferation potential than those of the low-ratio group (P < 0.05). 3-MA nmr A fascia equivalent was made with HVFs of the high-ratio group. In the subsequent animal study,

a well-organized neo-fascia formation containing HVFs could be traced up to 12 weeks after transplantation.

Our results suggest that a tissue-engineered fascia could be developed from HVFs in vitro and in vivo, which might be an effective treatment for POP in the future.”
“Background: Zinc plays an important role in antioxidant defense and the maintenance of cellular DNA integrity. However, no experimental human studies have been performed to examine the role of zinc status on DNA damage.

Objective: We evaluated the effects of dietary zinc depletion and repletion on DNA strand breaks, oxidative stress, and antioxidant defenses in healthy men.

Design: Nine healthy men with reported mean daily zinc intakes >11 mg/d were recruited. Subjects completed 3 consecutive dietary periods: baseline (days 1 to 13; 11 mg Zn/d), zinc depletion (days 14 to 55; 0.6 mg Zn/d for 1 wk and 4 mg Zn/d for 5 wk), and zinc repletion (days 56 to 83; 11 mg Zn/d for

4 wk with 20 mg supplemental Zn for first 7 d). Blood samples were collected on days 1, 13, 35, 55, and 83. DNA damage in peripheral blood cells, plasma oxidative stress, and antioxidant defense biomarkers were assessed.

Results: Dietary zinc depletion (6 wk) was associated with increased DNA strand breaks in peripheral blood cells (day 13 compared with day 55; P < 0.05), changes that were ameliorated by zinc repletion (day 55 compared with day 83; P, 0.05). Plasma zinc concentrations were negatively correlated with DNA strand breaks (r = -0.60, P = 0.006) during the zinc-depletion period. Plasma a-and c-tocopherol concentrations, plasma total antioxidant capacity, and erythrocyte superoxide dismutase activity did not change significantly, and plasma F-2-isoprostanes were unaffected by dietary period.

“Carbon monoxide (CO) is associated

with central n

“Carbon monoxide (CO) is associated

with central nervous system toxicity. However, evidence also indicates that PLX4032 CO can be protective, depending on its concentration. To determine if CO can be neuroprotective after ischemic brain injury, we subjected mice to transient middle cerebral artery occlusion and exposed them to different concentrations of CO. We found that in mice, low CO levels protected the brain from injury following 90-min transient focal ischemia and 48 h of reperfusion. When inhalation of 125 or 250 ppm CO began immediately at the onset of reperfusion, total hemispheric infarct volume was reduced by 32.1 +/- A 8.9% and 62.2 +/- A 14.4%, respectively; with an extended therapeutic window of 1-3 h after ischemia, CO inhalation also attenuated infarct volume significantly. Furthermore, early CO exposure limited brain edema formation by 3.2 +/- A 0.8% (125 ppm) and 2.6 +/- A 0.3% (250 ppm). Finally, CO inhalation significantly improved neurological deficit scores at 48 h of survival time after ischemia. Transient elevation

of carboxyhemoglobin levels selleckchem returned rapidly to baseline when CO exposure was stopped. These findings suggest a potential application of CO to treat brain ischemic stroke.”
“The radio-frequency (rf) power absorption due to a small hemispherical protrusion on a resonant cavity’s surface is computed analytically. This protrusion may assume arbitrary values of permittivity, permeability, and conductivity so that it may represent a foreign object. Under the

assumption that the protrusion radius, a, is small compared with the rf wavelength, the power dissipated in the protrusion by the rf electric field and by the rf magnetic field are calculated explicitly. It is found that, in general, the heating by the rf magnetic field is dominant when delta/a < 1, even for nonmagnetic materials, where delta is the skin depth associated JQ1 mw with the protrusion material. The field enhancement factors for both the rf electric field and the rf magnetic field on the protrusion are also calculated analytically. They are found to decrease as delta/a increases. They are spot checked against the MAXWELL 3D code. These field enhancement factors are also consistent with the published results in the delta=0 limit, in which case the protrusion may represent a small local bump on the surface of a superconducting cavity. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3131844]“
“Quality assurance and improvement (QA/QI) is a critical activity in medicine. The use of large-scale collaborative databases is increasingly essential to obtain enough reports with which to establish standards of practice and define the incidence of complications and risk/benefit ratios for rare events. Such projects can enhance local QA/QI endeavors by enabling institutions to obtain benchmark data against which to compare their performance and can be used for prospective analyses of inter-institutional differences to determine best practice.

“Background: Kidney function, expressed as glomerular filt

“Background: Kidney function, expressed as glomerular filtration rate ( GFR), is commonly estimated from serum creatinine ( Scr) and, when decreased, SBE-β-CD mouse may serve as a nonclassical risk factor for incident cardiovascular disease ( CVD). The ability of estimated GFR ( eGFR) to predict CVD events during 5-10 years of follow-up is assessed using data from the Strong Heart Study ( SHS), a large cohort with a high prevalence of diabetes.

Methods: eGFRs were calculated with the abbreviated Modification of Diet in Renal Disease study ( MDRD) and the Cockcroft-Gault ( CG)

equations. These estimates were compared in participants with normal and abnormal Scr. The association between eGFR and incident CVD was assessed.

Results: More subjects were labeled as

having low eGFR (<60 ml/min per TPCA-1 1.73 m(2)) by the MDRD or CG equation, than by Scr alone. When Scr was in the normal range, both equations labeled similar numbers of participants as having low eGFRs, although concordance between the equations was poor. However, when Scr was elevated, the MDRD equation labeled more subjects as having low eGFR. Persons with low eGFR had increased risk of CVD.

Conclusions: The MDRD and CG equations labeled more participants as having decreased GFR than did Scr alone. Decreased eGFR was predictive of CVD in this American Indian population with a high prevalence of obesity and type 2 diabetes mellitus.”
“Objective: To present the case of a hyperparathyroidism-jaw tumor (HPT-JT) patient with a novel nonsense mutation of the CDC73 gene.


We present the case of a patient with a history of three prior maxillectomies and two prior parathyroidectomies who presented with recurrent primary hyperparathyroidism (PHPT). We also briefly review the literature pertaining to HPT-JT.

Results: Genetic analysis revealed a novel nonsense mutation (c.85G>T; pGlu29) in exon 1 of CDC73. The patient’s son underwent genetic testing for a CDC73 mutation and was found to be negative.

Conclusion: HPT-JT is a rare condition characterized by PHPT and benign tumors of the mandible and maxilla. Up to 15% of HPT-JT patients with PHPT have parathyroid carcinoma. HPT-JT is associated with an inactivating mutation of CDC73, a gene that codes for the tumor suppressor protein parafibromin. This report expands our understanding of DZNeP ic50 the genetics underlying this rare disorder and emphasizes the importance of early detection in order to prevent hypercalcemic complications such as parathyroid carcinoma.”
“Purpose of reviewGender identity development is poorly understood but impacted by central nervous system (CNS) factors, genes, gonadal hormones and receptors, genitalia, and social/environmental factors. Gender identity disorder (GID) is the diagnostic term to describe persons discontent with the sex they were assigned at birth and/or the gender roles associated with that sex.

Among non-manual workers, there was an inverse linear relationshi

Among non-manual workers, there was an inverse linear relationship between educational level and AMI risk independent of CVRFs: compared with university educated individuals, the odds ratio (OR) for an AMI among those with a high school education was 1.63 (95% confidence interval [CI], 1.16-2.3), and among those with an elementary school education, 3.88 (95% CI, 2.79-5.39). No association between educational level and AMI risk was observed in manual workers. However, the AMI risk was higher in manual workers than non-manual university educated workers: in those with an elementary school education, the increased risk (OR=2.09; 95% CI, 1.59-2.75) was independent of CVRFs.

Conclusions. An association Panobinostat order was found

between socioeconomic status and AMI risk. The AMP risk was greatest in individuals with only an elementary school education, irrespective of CVRFs and social class, as indicated by occupation.”
“Background: The New Zealand population has both marginal selenium status and mild iodine deficiency. Adequate intakes of iodine and selenium are required for optimal thyroid function.

Objective: The aim of the study was to determine whether low selenium and iodine status compromises thyroid function in an older

New Zealand population.

Design: We investigated the effects of selenium HSP990 clinical trial and iodine supplementation in a double-blind, randomized, placebo-controlled trial in 100 Dunedin volunteers aged 60-80 y. Participants received 100 mu g Se/d as L-selenomethionine, 80 mu g I, 100 mu g Se + 80 mu g I, or placebo for 3 mo. Thyroid-stimulating hormone (TSH), free triiodothyronine (T-3), free thyroxine (T-4), thyroglobulin, plasma selenium, whole-blood

glutathione peroxidase (GPx) activity, and urinary iodine concentrations (UICs) were measured.

Results: Plasma selenium (P < 0.0001) and whole-blood GPx activity (P, 0.0001) increased from baseline to week 12 in the selenium and selenium plus iodine groups in comparison with the placebo group. Median UIC at baseline was 48 mu g/L (interquartile range: 31-79 mu g/L), which is indicative of moderate iodine deficiency. UIC increased AC220 in the iodine and selenium plus iodine groups and was significant only for the iodine group (P = 0.0014). Thyroglobulin concentration decreased by 24% and 13% of baseline in the iodine and selenium plus iodine groups in comparison with the placebo group (P = 0.009 and P = 0.108, respectively). No significant treatment effects were found for TSH, free T-3, free T-4, or ratio of T-3 to T-4.

Conclusions: Additional selenium improved GPx activity but not the thyroid hormone status of older New Zealanders. Iodine supplementation alleviated the moderate iodine deficiency and reduced elevated thyroglobulin concentrations. No synergistic action of selenium and iodine was observed. The trial was registered at www. ACTRN012605000368639. Am J Clin Nutr 2009;90:1038-46.

Jobs were categorized by degree of time spent working outdoors A

Jobs were categorized by degree of time spent working outdoors. A ten-year lag interval was included to account for disease latency. Odds ratios (ORs) and 95% confidence intervals (Cls) were estimated by logistic regression, with adjustment

for age, gender, and smoking.

Results: Outdoor work was inversely associated with risk of PD (outdoor only compared to indoor only): OR = 0.74, 95% CI 0.44-1.25. However, there was no trend in relation to portion of the workday spent laboring outdoors and PD risk.

Conclusion: Occupational sunlight exposure and other correlates of outdoor work is not likely to have a substantial role in the etiology of PD. (C) 2013 Elsevier Ltd. All rights reserved.”
“We have conducted the present case-control study to examine whether long-term variations in blood hemoglobin (Hb) levels within check details the normal range could detect subtle gastrointestinal bleeding in the early development of colorectal Dinaciclib datasheet cancer (CRC). A total of 1074 CRC cases aged 45-75 years that have been diagnosed with CRC and had normal Hb levels were frequency matched for age and sex with cancer-free individuals at a ratio of 10 controls per case.

Our retrospective analysis indicates that starting from 4 years prior to cancer diagnosis, a progressive significant (P < 0.001) decrement in Hb levels (0.28 g/dl per 6 months) was found among cases but not among controls. CRC patients were characterized in an on-going, long-term, logarithmic decrement in Hb levels. Such small changes within the normal Hb range could be missed by health providers, but automatically detected by computerized alert algorithms.. European Journal of Cancer

Prevention 19: 342-344 learn more (C) 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins.”
“Objectives: This study aimed to evaluate an atraumatic prototype electrode carrier for cochlear implantation, the FLEX(EAS) (20) electrode. This electrode is designed to preserve hearing and to achieve a 360-degree insertion.

Study Design: A cross-sectional human temporal bone study was conducted.

Setting: Preliminarily, the prototype electrode was inserted in a scala tympani model to measure the insertion force. Thirteen human temporal bones were acquired postmortem and implanted with the new device using the round window approach. Three of them were implanted under radiologic control to demonstrate the insertion path. After embedding, the remaining 10 temporal bones were sectioned undecalcified and examined macroscopically and histologically.

Main Outcome Measures: The insertion force was measured to determine intracochlear resistance peaks. The insertion angle was measured, and the degree of intracochlear trauma was determined.

Results: The round window approach caused cochlear trauma in 1 of 10 specimens. An exact 360-degree insertion was achieved in 7 of 10 specimens (mean overall insertion angle, 360 degrees).

Two patients developed cutaneous nodules at the sites of injectio

Two patients developed cutaneous nodules at the sites of injections; all others presented with intraoral nodules (labial/buccal or vestibular

mucosa) distant from the site of injections, suggestive of filler migration. Five of 21 cases presented with pain. Histopathologically, CHA presented as a diffuse mass of mauve-gray THZ1 solubility dmso or beige, nonrefractile spherules, and PLA as rice- or spindle-shaped, geometric, refractile bodies within circumscribed nodules.

Conclusions. Cutaneous injections of CHA and PLA fillers may induce granulomatous reactions presenting as intraoral nodules distant from the injection sites.”
“This study aimed to assess the impact of obstructive sleep apnea (OSA) due to adenotonsillar hypertrophy (ATH) on the global myocardial performance in children using tissue Doppler imaging (TDI) and to evaluate the reversibility of the disorder after adenotonsillectomy (AT). The study included 42 children with OSA due to ATH (mean age, 5 +/- A 3.14 years) as the study group and 45 age- and sex-matched healthy children (mean age, 5.2 +/- A 3.08 years) as the control group. Polysomnography and echocardiography were performed. Indexed left ventricular mass (LVMi), pulmonary artery systolic pressure, mean pulmonary artery pressure (mPAP), and pulmonary vascular resistance (PVR) were calculated by echocardiography. Tissue

Doppler imaging was used Galardin cell line to determine the left ventricular and right ventricular myocardial performance index (MPI) of patients and control subjects before and after AT. The patients were classified into mild OSA (apnea-hypopnea index [AHI] 1-5; n = 18)] and moderate to severe OSA (AHI > 5; n = 24) according to polysomnography findings. All the children in the control group had an AHI less than 1. They were treated using AT, then reevaluated by polysomnography and echocardiographic examination 6 to 8 months after Stattic order surgery. Results are described as mean +/- A standard deviation. The patients with OSA had higher pulmonary artery systolic pressure, mPAP, PVR, LVMi, and right ventricular diastolic diameter than the control subjects.

The patients with moderate to severe OSA showed more prominent changes than the patients with mild OSA, but the latter still differed significantly from the control subjects. The TDI-derived right ventricular MPI and left ventricular MPI measurements of the patients with OSA were higher (mean, 0.40 +/- A 0.08 vs 0.28 +/- A 0.01; p < 0.001) than those of the control subjects and (0.45 +/- A 0.05 vs 0.32 +/- A 0.05; p < 0.001) and correlated well with AHI and mPAP. In addition, mPAP was significantly correlated with AHI. Postoperatively, relief of OSA was validated by polysomnography, and a repeat of the echocardiographic parameters showed no significant differences between the patients and the control subjects.


reactions of N,N-dimethylacrylamide (DMA),


reactions of N,N-dimethylacrylamide (DMA), N-isopropylacrylamide (NIPA), and acrylamide (AAm) in aqueous clay (Laponite) dispersions have been investigated by rheometry using oscillatory deformation tests. The gelation profile of AAm polymerization obeys typical gelation kinetics, while a reverse behavior was observed during the DMA or NIPA polymerizations. In the latter cases, after an abrupt increase in elastic and viscous moduli at the start of the reaction, they both decrease continuously during the Whole Worse of the gelation process. Creep-recovery tests performed on the final hydrogels indicate that the time-dependent C59 Wnt cost viscoelastic response of the gels derived from AAm is distinctly different from the other gels. The retardation time of AAm gel is about twice that of DMA or NIPA gels indicating higher mobility of

the crosslink zones in the former gel. As a consequence, a larger amount of energy is dissipated during the deformation of nanocomposite hydrogels based on AAm. Different extent of interactions between the clay particles and the monomers explains the results of observations. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 116: 2328-2335, 2010″
“Objective-To characterize injuries (on the basis of type and severity of injury and affected region of the body) among dogs participating in agility training and competition events and examine associations between injury characteristics and perceived causes of injury.

Design-Internet-based, A-1155463 research buy retrospective, cross-sectional survey.

Animals-3,801 this website privately owned dogs participating in agility training or trials.

Procedures-A retrospective electronic survey was developed to investigate demographic factors for dogs and handlers, frequency of participation in agility training and competition, and perceived causes and characteristics of injuries acquired by dogs during agility-related activities. Respondents were handlers recruited through member lists of large canine agility associations in Canada and the United Kingdom and through promotion on an agility blog site. Associations between cause and anatomic site or type of injury and between injury severity (mild

vs severe) and setting (competition vs practice) were investigated.

Results-Surveys were received from 1,669 handlers of 3,801 agility dogs internationally. Handler-reported data indicated 1,209 of 3,801 (32%) dogs had >= 1 injury; of 1,523 analyzed injuries, the shoulder (349 injuries), back (282), and neck (189) regions and phalanges (202) were predominantly affected. Soft tissue injuries leg, strain [muscle or tendon injury; 807], sprain [ligament injury; 312], and contusion [200]) were common. Injuries were most commonly incurred during interactions with bar jumps, A-frames, and dog walk obstacles (260, 235, and 177 of 1,602 injuries, respectively). Anatomic site and type of injury were significantly associated with perceived cause of injury.

Therefore, the aim of this

Therefore, the aim of this BKM120 study was to investigate the occurrence of G(s)alpha mutation at the Arg(201) codon in hBMSCs and human trabecular bone cells (hTBCs, osteoblast-like cells). In addition, we evaluated the gene expression and protein secretion of amphiregulin from hBMSCs and hTBCs and assessed the biologic activity and possible mechanism of amphiregulin in our system.

Study design. Mutant hBMSCs from FD patients and hTBCs from disease-free

bone specimens of the same patient were successfully cultured. We studied the G(s)alpha mutations at the Arg(201) codon by means of polymerase chain reaction (PCR)-restriction fragment length polymorphism. Gene expression and protein secretion of amphiregulin in hBMSCs and hTBCs was confirmed by reverse-transcription (RT) PCR and Western blotting analysis. The modulation proliferation and possible mechanism of the exogenous addition of amphiregulin and epidermal growth factor receptor tyrosine kinase inhibitor (AG-1478) were assessed by using Wst-1 assays.

Results. The G(s)alpha mutations in clonal adherent mutant hBMSCs and hTBCs were successfully identified. We identified amphiregulin to be highly expressed in hBMSCs compared with hTBCs. The growth of hBMSCs was stimulated by the exogenous addition of amphiregulin and inhibited

by AG-1478.

Conclusions. The G(s)alpha-mutant hBMSCs were successfully identified, and amphiregulin may play a significant role in the proliferation of hBMSCs. (Oral Surg Oral check details Med Oral Pathol Oral Radiol Endod 2011;111:618-626)”
“Initiatives that establish species rarity as an indicator of conservation priority might be biased if they disregard important evolutionary and adaptive processes taking place in lower diversity communities and ecotones. Conservation policies regarding the Atlantic forest strongly emphasize the core formation (i.e. the rainforest stricto sensu) rather than the marginal habitats (e.g. restingas, swamps, and high altitude campos) and species that are rare/endemic.

To discuss this issue I revisit a hypothesis I have forwarded in 2002 that postulates that plant colonization of habitats marginal to the Atlantic rain forests of the State of Rio de Janeiro was largely related to terrestrial nurse plants that originally, in the rainforest habitat, were canopy plants such as epiphytes Caspase inhibitor or hemi-epiphytes. Adaptations to water and nutrient restrictions, typical of life in the canopy, granted success to such plants upon migration to sandy. swampy or rocky substrates in neighbouring areas. Many such species, then, behaved as nurse plants and favoured colonization of these more extreme habitats by a number of other rainforest species. I now review recent evidence that corroborate this hypothesis, while examining the nature of such nurse plants. In all marginal habitats, nurse plants are often highly abundant locally and have high ecophysiological vigour, while both widespread and endemic species are found among them.