Proteomic identification and functional characterization of prohibitin 1 and 2 in T cell activation, expansion, survival and disease

Several immune pathologies are the result of aberrant regulation of T lymphocytes. Pronounced T cell proliferation can result in autoimmunity or hematologic malignancy, whereas loss of T cell activity can manifest as immunodeficiency. Thus, there is a critical need to characterize the signal transduction pathways that mediate T cell activation so that novel and rational strategies to detect and effectively control T cell mediated disease can be achieved. ^ The first objective of this dissertation was to identify and characterize novel T cell regulatory proteins that are differentially expressed upon antigen induced activation. Using a functional proteomics approach, two members of the prohibitin (Phb) family of proteins, Phb1 and Phb2, were determined to be upregulated upon activation of primary human T cells. Furthermore, their regulated expression was dependent upon CD3 and CD28 signaling pathways which synergistically increased their expression. In contrast to previous reports of Phb nuclear localization, both proteins were determined to localize to the mitochondrial inner membrane of human T cells. Additionally, novel Phb phosphorylation sites were identified and characterized using mass spectrometry, phosphospecific antibodies and site directed mutagenesis. ^ Prohibitins have been proposed to play important roles in cancer development however the mechanism of action has not been elucidated. The second objective of this dissertation was to define the functional role of Phbs in T cell activity, survival and disease. Compared to levels in normal human T cells, Phb expression was higher in the human tumor T cell line Kit225 and subcellularly localized to the mitochondrion. Ablation of Phb expression by siRNA treatment of Kit225 cells resulted in disruption of mitochondrial membrane potential and significantly enhanced their sensitivity to cell death, suggesting they serve a protective function in T cells. Furthermore, Q-RT-PCR analysis of human oncology cDNA expression libraries indicated the Phbs may represent hematological cancer biomarkers. Indeed, Phb1 and Phb2 protein levels were 6-10 fold higher in peripheral blood mononuclear cells isolated from malignant lymphoma and multiple myeloma patients compared to healthy individuals. ^ Taken together, Phb1 and Phb2 are novel phosphoproteins upregulated during T cell activation and transformation to function in the maintenance of mitochondrial integrity and perhaps energy metabolism, thus representing previously unrecognized intracellular biomarkers and therapeutic targets for regulating T cell activation and hematologic malignancies. ^

A Su Salud Injury Prevention expansion: Analysis of injury prevention perceptions in a Hispanic community

Unintentional injury is the leading cause of death for American ages one to 44 and is ranked in the top ten causes of death for all age groups (CDC, 2006a). A Su Salud Injury Prevention was developed to address injury prevention awareness and education. The program is a mass media education campaign that uses role models, mass media, and community outreach to prevent injury. In 2009, University Health System (UHS) expanded the program. Baseline data were collected from 426 residents in targeted neighborhoods northwest of downtown San Antonio to support the expansion. The purpose of this study was to explore injury perceptions, knowledge, and behaviors of adults living in the expansion area, and define the predominant factors associated with these perceptions. A secondary aim was to assess community awareness and willingness to participate in the program.^ Survey results showed motor vehicle crashes (MVC), falls, drinking and driving, and guns and assaults were considered the most serious injures for adults. The most serious child injuries were MVC, abuse and neglect, falls, and head injuries. Residents were knowledgeable of state seatbelt policy, and over 90% responded as compliant for seatbelt and child car seat use. Most were knowledgeable about drinking and driving state policy and negative outcomes. However, 70% of those reporting driving under the influence of alcohol within the last year engaged in repeat high risk behavior. Men and residents under the age of 55 were more likely to engage in repeat drinking and driving (OR= 3.6, 7.0 respectively). Residents consider injury prevention an important issue, and have interest in a local injury prevention program. Younger women are the most likely to participate in a local program as potential role models and volunteers.^ Results from the study are summarized into an injury prevention and demographic profile of the community that will be used to develop tailored injury prevention messages to create a more effective program, and support program coordinators in effective community engagement. Results will also be used as a comparative basis for future evaluation of a behavioral injury prevention program focused on a predominantly Mexican-American community.^

Establishment, expansion and regeneration of aspen (Populus tremula) in the Torneträsk area, subarctic Sweden

In subarctic Sweden, recent decadal colonization and expansion of aspen (Populus tremula L.) were recorded. Over the past 100 years, aspen became c. 16 times more abundant, mainly as a result of increased sexual regeneration. Moreover, aspen now reach tree-size (>2 m) at the alpine treeline, an ecotone that has been dominated by mountain birch (Betula pubescens ssp. czerepanovii) for at least the past 4000 years. We found that sexual regeneration in aspen probably occurred seven times or more within the last century. Whereas sexual regeneration occurred during moist years following a year with an exceptionally high June-July temperature, asexual regeneration was favored by warm and dry summers. Disturbance to the birch forest by cyclic moth population outbreaks was critical in aspen establishment in the subalpine area. At the treeline, aspen colonization was less determined by these moth outbreaks, and was mainly restricted by summer temperature. If summer warming persists, aspen spread may continue in subarctic Sweden, particularly at the treeline. However, changing disturbance regimes, future herbivore population dynamics and the responses of aspen's competitors birch and pine to a changing climate may result in different outcomes.

Compression and expansion index and void ratio of samples from Lomonosov Ridge and Yermak Plateau

With the coupled use of multibeam swath bathymetry, high-resolution subbottom profiling and sediment coring from icebreakers in the Arctic Ocean, there is a growing awareness of the prevalence of Quaternary ice-grounding events on many of the topographic highs found in present water depths of <1000 m. In some regions, such as the Lomonosov Ridge and Yermak Plateau, overconsolidated sediments sampled through either drilling or coring are found beneath seismically imaged unconformities of glacigenic origin. However, there exists no comprehensive analysis of the geotechnical properties of these sediments, or how their inferred stress state may be related to different glacigenic processes or types of ice-loading. Here we combine geophysical, stratigraphic and geotechnical measurements from the Lomonosov Ridge and Yermak Plateau and discuss the glacial geological implications of overconsolidated sediments. The degree of overconsolidation, determined from measurements of porosity and shear strength, is shown to result from consolidation and/or deformation below grounded ice and, with the exception of a single region on the Lomonosov Ridge, cannot be explained by erosion of overlying sediments. We demonstrate that the amount and depth of porosity loss associated with a middle Quaternary (~ 790-950 thousand years ago - ka) grounding on the Yermak Plateau is compatible with sediment consolidation under an ice sheet or ice rise. Conversely, geotechnical properties of sediments from beneath late Quaternary ice-groundings in both regions, independently dated to Marine Isotope Stage (MIS) 6, indicate a more transient event commensurate with a passing tabular iceberg calved from an ice shelf.

Response of three krill species to hypoxia and warming: An experimental approach to oxygen minimum zones expansion in coastal ecosystems

To understand the adaptation of euphausiid (krill) species to oxygen minimum zones (OMZ), respiratory response and stress experiments combining hypoxia/reoxygenation exposure with warming were conducted. Experimental krill species were obtained from the Antarctic (South Georgia area), the Humboldt Current system (HCS, Chilean coast), and the Northern California Current system (NCCS, Oregon). Euphausia mucronata from the HCS shows oxyconforming or oxygen partial pressure (pO2)-dependent respiration below 80% air saturation (18 kPa). Normoxic subsurface oxygenation in winter posed a "high oxygen stress" for this species. The NCCS krill, Euphausia pacifica, and the Antarctic krill, Euphausia superba maintain respiration rates constant down to low critical pO2 values of 6 kPa (30% air saturation) and 11 kPa (55% air saturation), respectively. Antarctic krill had the lowest antioxidant enzyme activities, but the highest concentrations of the molecular antioxidant glutathione (GSH) and was not affected by 6 h exposure to moderate hypoxia. Temperate krill species had higher SOD (superoxide dismutase) values in winter than in summer, which relate to higher winter metabolic rate (E. pacifica). In all species, antioxidant enzyme activities remained constant during hypoxic exposure at habitat temperature. Warming by 7°C above habitat temperature in summer increased SOD activities and GSH levels in E. mucronata (HCS), but no oxidative damage occurred. In winter, when the NCCS is well mixed and the OMZ is deeper, +4°C of warming combined with hypoxia represents a lethal condition for E. pacifica. In summer, when the OMZ expands upwards (100 m subsurface), antioxidant defences counteracted hypoxia and reoxygenation effects in E. pacifica, but only at mildly elevated temperature (+2°C). In this season, experimental warming by +4°C reduced antioxidant activities and the hypoxia combination again caused mortality of exposed specimens. We conclude that a climate change scenario combining warming and hypoxia represents a serious threat to E. pacifica and, as a consequence, NCCS food webs.

Expansion of Asparagus Production and Exports in Peru

Peru is the one of the most important exporters of asparagus in the world. Its export volume of fresh asparagus is ranked number one, and its export volume of preserved asparagus number two, globally. The objective of this paper is to provide an overview of the recent trends in asparagus production and exports around the world and to analyze factors in the development of the Peruvian asparagus industry. The production of asparagus has spread geographically. The center of its production used to be in the principal consuming countries, such as France, Germany and the United States. Afterward, it spread to neighboring countries such as Spain and Mexico where production factors such as climate and labor costs are favorable. After the rise and fall of Taiwan as a major preserved white asparagus exporter, China and Peru replaced its position. Finally, in recent years, Peru expanded its fresh green asparagus exports to the U.S. market by taking advantage of the increasing demand for fresh vegetables and supplying produce in seasons when neither U.S. nor Mexican producers can harvest. In addition to the changing factors in the international market, there are several factors in the development of the industry: high yields of produce due to favorable climatic and soil conditions; the introduction of the drip irrigation system, which enabled desert cultivation; the integration of production and exports, which is indispensable for fresh produce exports; and the collective efforts of the industry with help from the public sector.

Family Business in Peru: Survival and Expansion under the Liberalization

It is argued that joint stock companies would be transformed from family firms to managerial firms with their development in size and scope. Such managerial firms would have many small shareholders; hence the ownership and management of the firm would be separated. However, in many developing countries including Peru, family businesses, in which families control both ownership and management, still play an important role in the national economy. After the liberalization of economy, which started in Peru in the 1990s, the national market has become more competitive due to the increase in participation of foreign capitals. To secure competitiveness, it is indispensable for family businesses to obtain management resources such as financial, human and technological resources from outside of the families. In order to do so without losing the control over ownership and management, Peruvian family businesses have incorporated companies with distinct characteristics to the extent that they can secure the control over ownership and management inside of their group. While keeping exclusive control of companies in traditional sectors, they actively seek alliance with other families and foreign capitals in competitive sectors. The management of companies with different degrees of control allows them to survive in today's rapidly changing business environment.

Development of Border Economic Zones in Thailand: Expansion of Border Trade and Formation of Border Economic Zones

In the wake of economic globalization and development in Thailand, movement of people and commodities at the Thai borders is also becoming pronounced. Economic interdependence between Thailand and neighboring countries is growing through border customhouses. As a policy, Thailand is trying to stimulate trade and investment with neighboring countries following the ACMECS (Ayeyawady-Chao Phraya-Mekong Economic Cooperation Strategy) scheme. In this report, first, movement of people and goods at the borders will be examined. Second, clarification of where and how development is proceeding will be presented. Last, this study will attempt to review the perspectives of policies on neighboring countries after Thaksin.

Variational Stereo Imaging of Oceanic Waves with Statistical Constraints

An image processing observational technique for the stereoscopic reconstruction of the wave form of oceanic sea states is developed. The technique incorporates the enforcement of any given statistical wave law modeling the quasi Gaussianity of oceanic waves observed in nature. The problem is posed in a variational optimization framework, where the desired wave form is obtained as the minimizer of a cost functional that combines image observations, smoothness priors and a weak statistical constraint. The minimizer is obtained combining gradient descent and multigrid methods on the necessary optimality equations of the cost functional. Robust photometric error criteria and a spatial intensity compensation model are also developed to improve the performance of the presented image matching strategy. The weak statistical constraint is thoroughly evaluated in combination with other elements presented to reconstruct and enforce constraints on experimental stereo data, demonstrating the improvement in the estimation of the observed ocean surface.

Offshore stereo measurements of gravity waves: classical epipolar and novel variational techniques

Stereo video techniques are effective for estimating the space-time wave dynamics over an area of the ocean. Indeed, a stereo camera view allows retrieval of both spatial and temporal data whose statistical content is richer than that of time series data retrieved from point wave probes. Classical epipolar techniques and modern variational methods are reviewed to reconstruct the sea surface from the stereo pairs sequentially in time. Current improvements of the variational methods are presented.

Space-time Reconstruction of Oceanic Sea States via Variational Stereo Methods

We present a remote sensing observational method for the measurement of the spatio-temporal dynamics of ocean waves. Variational techniques are used to recover a coherent space-time reconstruction of oceanic sea states given stereo video imagery. The stereoscopic reconstruction problem is expressed in a variational optimization framework. There, we design an energy functional whose minimizer is the desired temporal sequence of wave heights. The functional combines photometric observations as well as spatial and temporal regularizers. A nested iterative scheme is devised to numerically solve, via 3-D multigrid methods, the system of partial differential equations resulting from the optimality condition of the energy functional. The output of our method is the coherent, simultaneous estimation of the wave surface height and radiance at multiple snapshots. We demonstrate our algorithm on real data collected off-shore. Statistical and spectral analysis are performed. Comparison with respect to an existing sequential method is analyzed.

A Variational Stereo Method for the Three-Dimensional Reconstruction of Ocean Waves

We develop a novel remote sensing technique for the observation of waves on the ocean surface. Our method infers the 3-D waveform and radiance of oceanic sea states via a variational stereo imagery formulation. In this setting, the shape and radiance of the wave surface are given by minimizers of a composite energy functional that combines a photometric matching term along with regularization terms involving the smoothness of the unknowns. The desired ocean surface shape and radiance are the solution of a system of coupled partial differential equations derived from the optimality conditions of the energy functional. The proposed method is naturally extended to study the spatiotemporal dynamics of ocean waves and applied to three sets of stereo video data. Statistical and spectral analysis are carried out. Our results provide evidence that the observed omnidirectional wavenumber spectrum S(k) decays as k-2.5 is in agreement with Zakharov's theory (1999). Furthermore, the 3-D spectrum of the reconstructed wave surface is exploited to estimate wave dispersion and currents.