Effects of gait intervention using the draw-in maneuver on knee joint function and the thoracic kyphosis angle in knee osteoarthritis

BACKGROUND

To evaluate whether the knee adduction moment (KAM) could be reduced by a short instruction in the Draw-in (DI) maneuver in healthy adults, and whether knee joint function would improve with a longer DI gait intervention in patients with knee osteoarthritis (OA).

METHOD

In Study 1, healthy adults received 10 minutes supervised instruction in DI gait in and then practiced the gait independently for 10 minutes. Three-dimensional motion analysis measurement was performed in each phase. In Study 2, patients with OA performed a 20-minute DI gait intervention daily for 6 weeks. At baseline and after 6 weeks, knee pain, the Knee injury and Osteoarthritis Outcome Score, the MOS 8 item Short-Form Health Survey, thoracic kyphosis angle, knee joint range of motion, knee extension muscle strength, hip abduction muscle strength, and activity level were evaluated.

RESULTS

In Study 1, the DI gait to decrease KAM could be learning following only 10 minutes of instruction and 10 minutes of self-practice in healthy adults. In Study 2, knee pain was reduced by 19 % and the thoracic kyphosis angle was reduced by 2.6° after 6 weeks. No significant changes in other parameters were detected, and the implementation rate was 86 ± 14 %.

SIGNIFICANCE

In healthy adults, DI gait instruction for 10 minutes of instruction and 10 minutes of self-practice reduced the KAM. In patients with knee OA, 20 minutes of DI gait per day for 6 weeks may reduce knee pain and thoracic kyphosis.

Evaluating adaptive management frameworks for data-limited crustacean fisheries

Crustacean fisheries represent an increasingly important contribution to global landings, food security and economic growth, especially in developing countries. However, many productive and valuable crustacean fisheries in Asian countries are characterized by limited data availability, scientific capacity, and fisheries management. Adaptive management frameworks, which use past and emerging information to provide stock status information and management advice, have been touted as particularly applicable for managing capacity- and data-limited fisheries because they employ methods that can improve data collection and result in evaluations of stock and ecosystem status with varying levels of data and capacity. Here, we examined the application of three adaptive fisheries management frameworks (FISHE, FishPath, and DLMtool) to three typical Asian crustacean fisheries that offered contrasting data types and availability, governance, and management and socio-economic contexts. Our aim was to evaluate their suitability for crustacean fisheries and identify particular data and modeling needs and management gaps in these fisheries. We found that while each of the frameworks could effectively recommend suitable monitoring, assessment, and management options given particular contextual factors, there were also limitations with each approach. For example, FISHE took a more wholistic view of ecosystem and fisheries heath, while the other frameworks were more focused on particular aspects of management such as stock assessment (FishPath) and management strategy evaluation (MSE; DLMtool). Applications of each approach also highlighted particular challenges in collecting commercial catch data due to limited monetary investment and poorly designed monitoring programs, which further hindered the implementation of catch and effort limits. The three frameworks also shared common challenges when applied to crustacean species, mainly associated with misalignment with the unique life-histories of crustaceans compared to finfish. By comparing the outputs of the three frameworks, we highlighted their respective strengths and weaknesses and propose an integrated framework that incorporates elements of each of the three frameworks. This integration offers a more comprehensive adaptive roadmap tailored to crustacean fisheries, which involves a mix of qualitative and quantitative approaches that could be applied depending on contextual factors and capacities. To further improve the applicability of adaptive frameworks to crustacean fisheries, we suggest considering crustacean's unique life history and the effects of climate change and other environmental factors, strengthening participatory processes, and balancing socio-economic and ecological objectives.

Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Kimura's disease: effects of age on clinical presentation

BACKGROUND

Kimura's disease (KD) is known to be dominant among young Asian men, but it can also occur in middle- and advanced-aged people. The clinical characteristics of KD, especially by age, are not well known.

AIM

This study was performed to investigate the effects of age on the clinical characteristics of KD.

DESIGN

We conducted a case series study.

METHODS

All case studies of patients diagnosed with KD were collected via a PubMed search of studies published until August 2018. The data were analyzed by age group.

RESULTS

In total, 215 studies were reviewed (238 patients; mean age of 36 years). The male:female ratio was 4:1 overall, 17:1 in patients aged <20 years, 4:1 in patients aged 20-39 years and 2:1 in patients aged ≥40 years (P = 0.01). The percentage of patients with pruritus was 15.4% overall, 3.8% in patients aged <20 years, 15.5% in patients aged 20-39 years and 21.7% in patients aged ≥40 years (P = 0.02). The time to diagnosis was 5.3 years overall, 3.2 years in patients aged <20 years, 4.7 years in patients aged 20-39 years and 7.1 years in patients aged ≥40 years (P < 0.01).

CONCLUSIONS

The proportion of female patients affected the incidence of pruritus, and the time to diagnosis increased as the patients' age increased. There were no significant age-related differences in region/race, complications, multiplicity, laterality, anatomical distribution, maximum size, eosinophil count, immunoglobulin E level, initial treatment, recurrence or outcomes. This may be useful information for the diagnosis of KD.

Search for Electron Antineutrino Appearance in a Long-Baseline Muon Antineutrino Beam

Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40σ and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions.

P2263Prognostic impact of perceived social isolation in patients with heart failure

Background

Perceived social isolation (SI), the subjective sense of feelings of loneliness or isolation, has a negative impact on health outcomes, particularly in older adults. Although SI may also contribute to poor prognosis in patients with HF, evidence on the relationship between SI and outcomes in patients with HF is limited.

Purpose

The aim of this study was to investigate the relationship between SI and hospital readmission in patients with HF.

Methods

This study was a single center prospective cohort study. We consecutively enrolled 203 patients (mean age 72.9±11.7) who admitted for acute HF or exacerbation of chronic HF. At hospital discharge, we assessed perceived SI by using Lubben Social Network Scale - 6 (LSNS-6). Lower scores in LSNS-6 represents greater SI. Study outcome was rehospitalization for worsening HF within 180 days after discharge. We selected the optimal cutoff point of LSNS-6 that predict a worse outcome by the receiver operating characteristic (ROC) curve analysis. We investigate the association between SI and 180-days HF rehospitalization by using Cox proportional-hazard models, controlling for potential confounding factors.

Results

During follow up, A total of 40events (19.7%) were observed. The optimal cut-off point of LSNS-6 score was 17 points (the area under the ROC curve: 0.62, p<0.05, sensitivity: 82.5%, specificity 42.4%). Kaplan-Meier survival curves showed that those patients with greater SI (LSNS-6≤17) presented significantly higher HF rehospitalization rate (Figure). After adjusting for several pre-existing prognostic factors, LSNS-6≤17 was independently associated with HF rehospitalization (hazard ratio2.15,95% confidence interval 1.00–4.89).

Conclusion

The present study shows that SI is a independent predictor of HF rehospitalization in patients with HF. Assessing SI in the clinical practice with a brief screening tool may help identify patients with heart failure at greater risk of rehospitalization.

P6332Prevalence and prognostic impact of sarcopenia identified according to Asia Working Group for Sarcopenia definition in non-dependent elderly patients with heart failure

Background

Sarcopenia is a geriatric syndrome characterized by loss of muscle mass and muscle function. As the population ages, there is a growing worldwide interest in the intersection of sarcopenia and heart failure (HF). However, estimates of the prevalence of sarcopenia in HF vary widely because of difference in diagnostic criteria. Although the Asian Working Group of Sarcopenia (AWGS) has announced a consensus on the diagnostic criteria of sarcopenia in Asian people, the prevalence and prognostic impact of sarcopenia based on AWGS criteria in patients with HF remains unclear.

Purpose

The aim of this study was to investigate the prevalence and predictive value of sarcopenia identified according to AWGS definition in non-dependent elderly patients with HF.

Methods

This study was a prospective, single-center cohort study in Japan. We consecutively enrolled 274 patients, aged 65 years or older, hospitalized due to acute HF or acute exacerbation of chronic HF and who were able to walk at least 20 m at discharge. Patients with severe cognitive or psychiatric disorders were excluded. Patients with implantable cardiac pacemaker or cardioverter defibrillator were also excluded because skeletal muscle mass was estimated by using bioimpedance analysis. At hospital discharge, we collected data on age, gender, left ventricular ejection fraction, brain natriuretic peptide, estimate glomerular filtration rate, body mass index and sarcopenia. Sarcopenia was diagnosed according to the AWGS criteria: low skeletal muscle index (<7.0 kg/m2 in men, <5.7 kg/m2 in women) and either slow usual walking speed (<0.8 m/s) or low handgrip strength (<26 kg in men, <17 kg in women). Study outcome was rehospitalization for worsening HF within 180 days after discharge. We assessed the independent association between sarcopenia and HF rehospitalization by using multivariate Cox proportional hazards regression analysis.

Results

In this study, a total of 199 patents (43.4%) fulfilled sarcopenia criteria at discharge. During follow-up, 57 patients (20.8%) readmitted for HF. Kaplan-Meier survival curves showed that patients with sarcopenia had significantly lower event-free survival than those without sarcopenia (Figure). After adjusting for other prognostic factors, sarcopenia was independently associated with HF rehospitalization (hazard ratio: 2.31, 95% confidence interval: 1.20–4.53).

Conclusion

Based on AWGS criteria, sarcopenia is highly prevalent even among non-dependent elderly HF patients, and is an independent strong predictor of rehospitalization for worsening HF. AWGS criteria for sarcopenia may be useful for risk prediction in HF.

P6360Prognostic value of polypharmacy in patients with heart failure

Background

Polypharmacy creates an increased patient's burden by drug-drug interactions and poor adherence. However, there are very few studies available evaluating the association of polypharmacy with hospital readmission in patients with heart failure (HF).

Purpose

The aim of this study was to investigate the impact of polypharmacy on hospital readmission for HF.

Methods

We enrolled 1253 patients who were hospitalized with acute heart failure (AHF) or acute exacerbation of chronic heart failure in the Kitakawachi Clinical Background and Outcome of Heart Failure Registry (KICKOFF Registry) from April 2015 to July 2018 (age 78.1±11.5 years, male 51.4%). Our Registry is a prospective multicenter community-based cohort study of HF patients in Japan. The inclusion criteria for the registry was a diagnosis of HF during hospitalization according to the Framingham criteria, and there were no exclusion criteria. From data at discharge, we collected data on clinical characteristics, medication schedule, and social backgrounds. We defined polypharmacy as the use of seven or more medications. The primary end point was HF rehospitalization within 1 year after discharge. Cox proportional hazards regression analysis was used to describe the association between polypharmacy and 1-year HF rehospitalization, controlling for potential confounding factors.

Results

In this study, the prevalence of polypharmacy was 59.7% of all patients. Patients with polypharmacy were more likely to have comorbidities such as hypertension, dyslipidemia, diabetes, chronic kidney disease, coronary artery disease and dementia. They also had lower EF (50.9±0.64 vs 53.6±0.80, p<0.01), compared to patients without polypharmacy. There was no significant difference in age, gender and BMI, compared to patients without polypharmacy. During the follow-up period, a total of 278 patients (24.9%) were readmitted for HF. In Kaplan-Meier analyses, hospital readmission for HF during 1-year follow-up was significantly higher in patients with polypharmacy (p<0.01) (figure). After adjusting for gender, age, EF, and the other co-morbidities, polypharmacy was independently associated with higher risk of rehospitalization for HF (hazard ratio 1.28, 95% confidence interval, 1.07–1.52, p<0.01).

Conclusion

Polypharmacy is an independent predictor of hospital readmission for HF. Our study suggests the need for developing an effective strategy to choose the appropriate drugs in patients with HF.

Acknowledgement/Funding

Nakajima Steel Pipe

Cr2Te3 Thin Films for Integration in Magnetic Topological Insulator Heterostructures

Chromium telluride compounds are promising ferromagnets for proximity coupling to magnetic topological insulators (MTIs) of the Cr-doped (Bi,Sb)₂(Se,Te)₃ class of materials as they share the same elements, thus simplifying thin film growth, as well as due to their compatible crystal structure. Recently, it has been demonstrated that high quality (001)-oriented Cr₂Te₃ thin films with perpendicular magnetic anisotropy can be grown on c-plane sapphire substrate. Here, we present a magnetic and soft x-ray absorption spectroscopy study of the chemical and magnetic properties of Cr₂Te₃ thin films. X-ray magnetic circular dichroism (XMCD) measured at the Cr L_2,3 edges gives information about the local electronic and magnetic structure of the Cr ions. We further demonstrate the overgrowth of Cr₂Te₃ (001) thin films by high-quality Cr-doped Sb₂Te₃ films. The magnetic properties of the layers have been characterized and our results provide a starting point for refining the physical models of the complex magnetic ordering in Cr₂Te₃ thin films, and their integration into advanced MTI heterostructures for quantum device applications.

Search for CP Violation in Neutrino and Antineutrino Oscillations by the T2K Experiment with 2.2×10^{21} Protons on Target

The T2K experiment measures muon neutrino disappearance and electron neutrino appearance in accelerator-produced neutrino and antineutrino beams. With an exposure of 14.7(7.6)×10^{20} protons on target in the neutrino (antineutrino) mode, 89 ν_{e} candidates and seven anti-ν_{e} candidates are observed, while 67.5 and 9.0 are expected for δ_{CP}=0 and normal mass ordering. The obtained 2σ confidence interval for the CP-violating phase, δ_{CP}, does not include the CP-conserving cases (δ_{CP}=0, π). The best-fit values of other parameters are sin^{2}θ_{23}=0.526_{-0.036}^{+0.032} and Δm_{32}^{2}=2.463_{-0.070}^{+0.071}×10^{-3}  eV^{2}/c^{4}.

Deep-learning-based, computer-aided classifier developed with a small dataset of clinical images surpasses board-certified dermatologists in skin tumour diagnosis

BACKGROUND

Application of deep-learning technology to skin cancer classification can potentially improve the sensitivity and specificity of skin cancer screening, but the number of training images required for such a system is thought to be extremely large.

OBJECTIVES

To determine whether deep-learning technology could be used to develop an efficient skin cancer classification system with a relatively small dataset of clinical images.

METHODS

A deep convolutional neural network (DCNN) was trained using a dataset of 4867 clinical images obtained from 1842 patients diagnosed with skin tumours at the University of Tsukuba Hospital from 2003 to 2016. The images consisted of 14 diagnoses, including both malignant and benign conditions. Its performance was tested against 13 board-certified dermatologists and nine dermatology trainees.

RESULTS

The overall classification accuracy of the trained DCNN was 76·5%. The DCNN achieved 96·3% sensitivity (correctly classified malignant as malignant) and 89·5% specificity (correctly classified benign as benign). Although the accuracy of malignant or benign classification by the board-certified dermatologists was statistically higher than that of the dermatology trainees (85·3% ± 3·7% and 74·4% ± 6·8%, P < 0·01), the DCNN achieved even greater accuracy, as high as 92·4% ± 2·1% (P < 0·001).

CONCLUSIONS

We have developed an efficient skin tumour classifier using a DCNN trained on a relatively small dataset. The DCNN classified images of skin tumours more accurately than board-certified dermatologists. Collectively, the current system may have capabilities for screening purposes in general medical practice, particularly because it requires only a single clinical image for classification.

Comparison of hemodynamic parameters that can predict an aneurysmal rupture: 20 patient-specific models experiment

Hemodynamic analysis of cerebral aneurysms is widely performed to understand the mechanism of aneurysmal rupture. Computational fluid dynamics (CFD) studies have suggested that several hemodynamic parameters are associated with such ruptures. However, a number of factors remain to be addressed to correlate these parameters with aneurysmal ruptures, especially under analytical conditions. Specifically, CFD analysis is often performed with rigid wall models due to computational cost limitations. Here, to evaluate the effects of the deformation of the aneurysmal wall, experimental flow measurement with elastic models under pulsating conditions was conducted using three-dimensional particle image velocimetry (3D PIV). By analyzing 20 patient-specific, elastic, silicone aneurysm models, the hemodynamic parameters of ruptured and unruptured aneurysms were statistically compared to identify the variables that can effectively predict an aneurysmal rupture. Our analyses yielded three parameters (average wall shear stress ratio, in-phase deviation ratio, and pressure difference) which could effectively predict an aneurysmal rupture. These results suggested that measurement of wall shear stress (WSS) at both the aneurysm dome and parent artery is important and that pressure difference can also be a potential indicator of aneurysmal rupture.

Abstract P5-09-08: Molecular evaluation of Peruvian patients with hereditary breast cancer reveals a novel germline mutation in BRCA1

Background

Breast cancer is the leading cancer in women worldwide, while in Peru is the second most frequent cancer with a high incidence of triple negative breast cancers (21%). There is no previous information about BRCA1/BRCA2 mutations in Peruvian high-risk breast cancer patients. Prior studies from International diagnostic laboratories only presented results of our population as a pooled Hispanic data. Our aim was to characterize mutations in BRCA1/BRCA2 genes in Peruvian patients with breast cancer with hereditary patterns.

Methods

We evaluated mutations in BRCA1/BRCA2 genes by Sanger sequencing and large genomic rearrangements by multiplex ligation-dependent probe amplification (MLPA) in 18 families with hereditary breast cancer criteria identified at the Breast Unit of Oncosalud-AUNA (Lima-Peru). Molecular analysis was done in the facilities of Genetics and Molecular Biology Center at the San Martin de Porres University (Lima-Peru).

Results

Sequencing identified 4 pathogenic mutations in 4/18 families, three previously detected (BRCA1: c.302-1G&gt;C y c.815_824dup10; BRCA2: c.5946delT) and a novel germline mutation in exon 15 of BRCA1 (c.4647_4648dupAA, ClinVar SCV000256598.1) producing a frameshift variant. MLPA revealed 2 amplifications in exon 7 (duplication and triplication) in BRCA1 in unrelated patients with potential pathogenic effects, one of this co-existed with the BRCA2: c.5946delT mutation. In addition, three variants of uncertain significance were found (c.140G&gt;T, in exon 5 of BRCA1 and c.464G&gt;A and c.938C&gt;T in exon 5 and 10 of BRCA2, respectively).

Conclusions

After a comprehensive evaluation we found an alteration rate of 27.8% (5/18) in BRCA1/BRCA2 in families with criteria for hereditary breast cancer. We reported BRCA1 c.4647_4648dupAA as a novel mutation. Further studies including a larger sample size of Peruvian patients should evaluate the prevalence or founder effect of this mutation in our population.

Citation Format: Ponce J, Vigil C, Araujo JM, Castañeda C, Calderon G, Buleje JL, Acosta O, Danos P, Huaman F, Guevara-Fujita ML, Aguilar A, Pinto JA, Gomez HL, Fujita R. Molecular evaluation of Peruvian patients with hereditary breast cancer reveals a novel germline mutation in BRCA1 [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-09-08.

Embracing thresholds for better environmental management

Three decades of study have revealed dozens of examples in which natural systems have crossed biophysical thresholds (‘tipping points’)—nonlinear changes in ecosystem structure and function—as a result of human-induced stressors, dramatically altering ecosystem function and services. Environmental management that avoids such thresholds could prevent severe social, economic and environmental impacts. Here, we review management measures implemented in ecological systems that have thresholds. Using Ostrom's social–ecological systems framework, we analysed key biophysical and institutional factors associated with 51 social–ecological systems and associated management regimes, and related these to management success defined by ecological outcomes. We categorized cases as instances of prospective or retrospective management, based upon whether management aimed to avoid a threshold or to restore systems that have crossed a threshold. We find that smaller systems are more amenable to threshold-based management, that routine monitoring is associated with successful avoidance of thresholds and recovery after thresholds have been crossed, and that success is associated with the explicit threshold-based management. These findings are powerful evidence for the policy relevance of information on ecological thresholds across a wide range of ecosystems.

A New Grip Strength Measuring Device for Detailed Evaluation of Muscle Contraction among the Elderly

BACKGROUND

We developed a new grip strength measuring device, which considers the time axis, for evaluating muscle contraction in detail in elderly people.

OBJECTIVES

To present the novel device and preliminary results concerning agility in gripping.

DESIGN

Cross-sectional analysis.

PARTICIPANTS

One hundred and twenty-one older persons (48 men and 73 women, mean age 74.4 years) referring for memory disorders to the outpatient clinic of our institute.

MEASUREMENTS

A novel device taking advantage of an industrial force-gauge was developed for measuring gripping performance. The instrument graphically described participants' strength production. Nine indices were derived from four points identified by the graph: 1) starting point ("Go signal"), 2) time when gripping starts, 3) turning point (TP) when the inclination of the curve depicting strength production changes, and 4) peak of strength production. Results obtained from the study sample of older persons were compared (as ratios) to a control group of 30 healthy young adults in their thirties in order to calculate age-related decline rates. Differences between right and left side were compared.

RESULTS

A significant difference was observed between right and left hands concerning the time to reach peak of strength, and time from TP to strength peak in both men and women. For women, the following indices were also significantly different: time to reach TP, strength at TP, time from TP to strength peak, curve inclination from TP to strength peak, and ratio of TP strength divided by peak strength.

CONCLUSION

Declines in several indices of gripping agility were measured. The parameters which were more closely related to time than strength itself showed significant differences between right and left hands, especially in women.

A transactional and collaborative approach to reducing effects of bottom trawling

Private-sector financial and legal transactions have long been used to protect terrestrial habitats and working landscapes, but less commonly to address critical threats in marine environments. Transferrable and marketable fishing privileges, including permits and quotas, make it possible to use private-sector transactions as conservation strategies to address some fishery management issues. Abating the effects of bottom trawling on the seafloor and bycatch and discard associated with the practice has proven challenging. On the Central Coast of California, The Nature Conservancy (TNC), Environmental Defense Fund, local fishers and local, state, and federal authorities worked collaboratively to protect large areas of the seafloor from bottom trawling for groundfish while addressing economic impacts of trawl closures. Contingent on the adoption of trawl-closure areas by a federal regulatory agency, TNC used private funds to purchase federal groundfish trawl permits and vessels from willing sellers. Trawl-closure areas were designed collaboratively by combining regional biological diversity and fisheries data with local fishers' knowledge. The private transactional strategy was designed to remedy some deficiencies in previous federal buyouts, to mitigate economic impacts from trawl closures, and to carefully align with a public regulatory process to protect "essential fish habitat" under the Magnuson-Stevens Fishery Conservation and Management Act. This collaborative effort protected 1.5 million ha (3.8 million acres) of seafloor, reduced trawl effort in the area by 50%, and set a precedent for collaborative partnerships between conservation and fishing interests. This is the first time a large conservation organization has taken an ownership position in a fishery and demonstrates how nongovernmental organizations can invest in fisheries to improve environmental and economic performance.

Prothymosin-alpha plays a defensive role in retinal ischemia through necrosis and apoptosis inhibition

Prothymosin-alpha (ProTalpha) causes a switch in cell death mode from necrosis to neurotrophin-reversible apoptosis in primary cultured cortical neurons. In the present study, post-ischemic administration (3 or 24 h, intravenously) of recombinant mouse ProTalpha without neurotrophins completely prevented ischemia-induced retinal damage accompanying necrosis and apoptosis, as well as dysfunction assessed by electroretinogram. Treatments with anti-erythropoietin (EPO) or brain-derived neurotrophic factor (BDNF) immunoglobulin G (IgG) reversed ProTalpha-induced inhibition of apoptosis. ProTalpha upregulated retinal EPO and BDNF levels in the presence of ischemia. Moreover, intravitreous administration of anti-ProTalpha IgG or an antisense oligodeoxynucleotide for ProTalpha accelerated ischemia-induced retinal damage. We also observed that ischemia treatment caused a depletion of ProTalpha from retinal cells. Altogether, these results suggest that the systemic administration of ProTalpha switches ischemia-induced necrosis to apoptosis, which in turn is inhibited by neurotrophic factors upregulated by ProTalpha and ischemia. ProTalpha released upon ischemic stress was found to have a defensive role in retinal ischemia.