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1.  Myosin-Va and Dynamic Actin Oppose Microtubules to Drive Long-Range Organelle Transport 
Current Biology  2014;24(15):1743-1750.
In animal cells, microtubule and actin tracks and their associated motors (dynein, kinesin, and myosin) are thought to regulate long- and short-range transport, respectively [1–8]. Consistent with this, microtubules extend from the perinuclear centrosome to the plasma membrane and allow bidirectional cargo transport over long distances (>1 μm). In contrast, actin often comprises a complex network of short randomly oriented filaments, suggesting that myosin motors move cargo short distances. These observations underpin the “highways and local roads” model for transport along microtubule and actin tracks [2]. The “cooperative capture” model exemplifies this view and suggests that melanosome distribution in melanocyte dendrites is maintained by long-range transport on microtubules followed by actin/myosin-Va-dependent tethering [5, 9]. In this study, we used cell normalization technology to quantitatively examine the contribution of microtubules and actin/myosin-Va to organelle distribution in melanocytes. Surprisingly, our results indicate that microtubules are essential for centripetal, but not centrifugal, transport. Instead, we find that microtubules retard a centrifugal transport process that is dependent on myosin-Va and a population of dynamic F-actin. Functional analysis of mutant proteins indicates that myosin-Va works as a transporter dispersing melanosomes along actin tracks whose +/barbed ends are oriented toward the plasma membrane. Overall, our data highlight the role of myosin-Va and actin in transport, and not tethering, and suggest a new model in which organelle distribution is determined by the balance between microtubule-dependent centripetal and myosin-Va/actin-dependent centrifugal transport. These observations appear to be consistent with evidence coming from other systems showing that actin/myosin networks can drive long-distance organelle transport and positioning [10, 11].
Graphical Abstract
•Microtubules are essential for centripetal, but not centrifugal, melanosome transport•Myosin-Va and a dynamic actin pool drive long-range centrifugal melanosome transport•Myosin-Va is a processive plus-end-directed motor, and not a tether, in melanocytes•Opposing myosin-Va/actin and microtubule forces regulate melanosome distribution
In animal cells, microtubules and actin are thought to regulate long- and short-range transport, respectively. Here, Evans et al. test the contribution of these systems to organelle transport using melanocyte pigment granules as a model. Surprisingly, they find that myosin-Va and dynamic actin drive long-range transport to the membrane.
PMCID: PMC4131108  PMID: 25065759
2.  Extracellular microRNAs are dynamic non-vesicular biomarkers of muscle turnover 
Nucleic Acids Research  2013;41(20):9500-9513.
Extracellular microRNAs (miRNAs) are promising biomarkers of the inherited muscle wasting condition Duchenne muscular dystrophy, as they allow non-invasive monitoring of either disease progression or response to therapy. In this study, serum miRNA profiling reveals a distinct extracellular miRNA signature in dystrophin-deficient mdx mice, which shows profound dose-responsive restoration following dystrophin rescue. Extracellular dystrophy-associated miRNAs (dystromiRs) show dynamic patterns of expression that mirror the progression of muscle pathology in mdx mice. Expression of the myogenic miRNA, miR-206 and the myogenic transcription factor myogenin in the tibialis anterior muscle were found to positively correlate with serum dystromiR levels, suggesting that extracellular miRNAs are indicators of the regenerative status of the musculature. Similarly, extracellular dystromiRs were elevated following experimentally-induced skeletal muscle injury and regeneration in non-dystrophic mice. Only a minority of serum dystromiRs were found in extracellular vesicles, whereas the majority were protected from serum nucleases by association with protein/lipoprotein complexes. In conclusion, extracellular miRNAs are dynamic indices of pathophysiological processes in skeletal muscle.
PMCID: PMC3814379  PMID: 23945935
3.  Implementation of an Intersectoral Program to Eliminate Human and Canine Rabies: The Bohol Rabies Prevention and Elimination Project 
The province of Bohol, located in the Visayas islands region in the Philippines has a human population of 1.13 million and was the 4th highest region for human rabies deaths in the country, averaging 10 per year, prior to the initiation of the Bohol Rabies Prevention and Elimination Project (BRPEP).
The BRPEP was initiated in 2007 with the goal of building a sustainable program that would prevent human rabies by eliminating rabies at its source, in dogs, by 2010. This goal was in line with the Philippine National Rabies Program whose objective is to eliminate rabies by 2020.
The intersectoral BRPEP was launched in 2007 and integrated the expertise and resources from the sectors of agriculture, public health and safety, education, environment, legal affairs, interior and local government. The program included: increasing local community involvement; implementing dog population control; conducting mass dog vaccination; improving dog bite management; instituting veterinary quarantine; and improving diagnostic capability, surveillance and monitoring. Funding was secured from the national government, provincial, municipal and village units, dog owners, NGOs, the regional office of the WHO, the UBS Optimus Foundation, and the Global Alliance for Rabies Control. The BRPEP was managed by the Bohol Rabies Prevention and Eradication Council (BRPEC) under the jurisdiction of the Governor of Bohol. Parallel organizations were created at the municipal level and village level. Community volunteers facilitated the institution of the program. Dog population surveys were conducted to plan for sufficient resources to vaccinate the required 70% of the dogs living in the province. Two island-wide mass vaccination campaigns were conducted followed by “catch up” vaccination campaigns. Registration of dogs was implemented including a small fee that was rolled back into the program to maintain sustainability. Children were educated by introducing rabies prevention modules into all elementary schools in Bohol. Existing public health legislation at the national, provincial, and municipal level strengthened the enforcement of activities. A Knowledge, Attitude and Practices (KAP) survey was conducted in 2009 to evaluate the educational knowledge of the population. Increased surveillance was instituted to ensure that dogs traveling into and out of the province were vaccinated against rabies. Human and animal cases of rabies were reported to provincial and national authorities.
Key Results
Within the first 18 months of the BRPEP, human rabies deaths had decreased annually from 0.77 to 0.37 to zero per 100,000 population from 2007–2009. Between October 2008 and November 2010 no human and animal cases were detected. Increased surveillance on the island detected one suspected human rabies case in November 2010 and one confirmed case of canine rabies in April 2011. Two mass vaccination campaigns conducted in 2007 and 2008 successfully registered and vaccinated 44% and 70% of the dogs on the island. The additional surveillance activities enabled a mobilization of mop up vaccination activities in the region where the human and canine case was located. Due to the increased effective and continuous surveillance activities, rabies was stopped before it could spread to other areas on the island. The program costs totaled USD 450,000. Registration fees collected to maintain the program amounted to USD 105,740 and were re-allocated back into the community to sustain the program.
Author Summary
The Province of Bohol, Philippines has eliminated dog and human rabies in less than three years by empowering the community and implementing an intersectoral strategy. In 2006, Bohol ranked 4th highest in the Philippines for human rabies, averaging 10 deaths per year. Launched in 2007, the program utilized a social awareness campaign, dog population control, mass dog vaccination campaigns, improved dog bite management and veterinary quarantine, a new diagnostic laboratory, expanded surveillance, and the inclusion of education modules into the school curriculum. Improving community compliance to existing national and provincial rabies laws and engaging volunteers to help conduct the project was a key to success. The program, led by the Governor of Bohol, was administered through a group of departments working together at a provincial and local level, and supervised through the Office of the Provincial Veterinarian. Financial support came through the Governor and several NGOs including the Global Alliance for Rabies Control. The program is self-sustaining, through a small dog registration fee fed back into the program, through the continuing education of children in their classrooms, and through the dedicated efforts of over 15,000 staff and volunteers throughout the island.
PMCID: PMC3516573  PMID: 23236525
4.  Dimerization of ABCG2 Analysed by Bimolecular Fluorescence Complementation 
PLoS ONE  2011;6(10):e25818.
ABCG2 is one of three human ATP binding cassette transporters that are functionally capable of exporting a diverse range of substrates from cells. The physiological consequence of ABCG2 multidrug transport activity in leukaemia, and some solid tumours is the acquisition of cancer multidrug resistance. ABCG2 has a primary structure that infers that a minimal functional transporting unit would be a homodimer. Here we investigated the ability of a bimolecular fluorescence complementation approach to examine ABCG2 dimers, and to probe the role of individual amino acid substitutions in dimer formation. ABCG2 was tagged with fragments of venus fluorescent protein (vYFP), and this tagging did not perturb trafficking or function. Co-expression of two proteins bearing N-terminal and C-terminal fragments of YFP resulted in their association and detection of dimerization by fluorescence microscopy and flow cytometry. Point mutations in ABCG2 which may affect dimer formation were examined for alterations in the magnitude of fluorescence complementation signal. Bimolecular fluorescence complementation (BiFC) demonstrated specific ABCG2 dimer formation, but no changes in dimer formation, resulting from single amino acid substitutions, were detected by BiFC analysis.
PMCID: PMC3185054  PMID: 21991363
5.  Recent Advances in Prevention and Control of Rabies 
PMCID: PMC3180785  PMID: 21991447
6.  Renewed Global Partnerships and Redesigned Roadmaps for Rabies Prevention and Control 
Canine rabies, responsible for most human rabies deaths, is a serious global public health concern. This zoonosis is entirely preventable, but by focusing solely upon rabies prevention in humans, this “incurable wound” persists at high costs. Although preventing human deaths through canine rabies elimination is feasible, dog rabies control is often neglected, because dogs are not considered typical economic commodities by the animal health sector. Here, we demonstrate that the responsibility of managing rabies falls upon multiple sectors, that a truly integrated approach is the key to rabies elimination, and that considerable progress has been made to this effect. Achievements include the construction of global rabies networks and organizational partnerships; development of road maps, operational toolkits, and a blueprint for rabies prevention and control; and opportunities for scaling up and replication of successful programs. Progress must continue towards overcoming the remaining challenges preventing the ultimate goal of rabies elimination.
PMCID: PMC3135331  PMID: 21776359
7.  Evaluation of Cost-Effective Strategies for Rabies Post-Exposure Vaccination in Low-Income Countries 
Prompt post-exposure prophylaxis (PEP) is essential in preventing the fatal onset of disease in persons exposed to rabies. Unfortunately, life-saving rabies vaccines and biologicals are often neither accessible nor affordable, particularly to the poorest sectors of society who are most at risk and upon whom the largest burden of rabies falls. Increasing accessibility, reducing costs and preventing delays in delivery of PEP should therefore be prioritized.
Methodology/Principal Findings
We analyzed different PEP vaccination regimens and evaluated their relative costs and benefits to bite victims and healthcare providers. We found PEP vaccination to be an extremely cost-effective intervention (from $200 to less than $60/death averted). Switching from intramuscular (IM) administration of PEP to equally efficacious intradermal (ID) regimens was shown to result in significant savings in the volume of vaccine required to treat the same number of patients, which could mitigate vaccine shortages, and would dramatically reduce the costs of implementing PEP. We present financing mechanisms that would make PEP more affordable and accessible, could help subsidize the cost for those most in need, and could even support new and existing rabies control and prevention programs.
We conclude that a universal switch to ID delivery would improve the affordability and accessibility of PEP for bite victims, leading to a likely reduction in human rabies deaths, as well as being economical for healthcare providers.
PMCID: PMC3050908  PMID: 21408121
8.  Rabies in the 21st Century 
PMCID: PMC2846934  PMID: 20361028
9.  Recent progress in satellite cell/myoblast engraftment – relevance for therapy 
The Febs Journal  2013;280(17):4281-4293.
There is currently no cure for muscular dystrophies, although several promising strategies are in basic and clinical research. One such strategy is cell transplantation with satellite cells (or their myoblast progeny) to repair damaged muscle and provide dystrophin protein with the aim of preventing subsequent myofibre degeneration and repopulating the stem cell niche for future use. The present review aims to cover recent advances in satellite cell/myoblast therapy and to discuss the challenges that remain for it to become a realistic therapy.
PMCID: PMC3795440  PMID: 23560812
cell therapy; Duchenne muscular dystrophy; mdx mouse; muscular dystrophy; myoblasts; satellite cells; skeletal muscle regeneration

Results 1-9 (9)