Wildlife health surveillance: gaps, needs and opportunities.

Disease emergence represents a global threat to public health, economy and biological conservation. Most emerging zoonotic diseases have an animal origin, most commonly from wildlife. To prevent their spread and to support the implementation of control measures, disease surveillance and reporting systems are needed, and due to globalisation, these activities should be carried out at the global level. To define the main gaps affecting the performance of wildlife health surveillance and reporting systems globally, the authors analysed data from a questionnaire sent to National Focal Points of the World Organisation for Animal Health that inquired on structure and limits of wildlife surveillance and reporting systems in their territories. Responses from 103 Members, covering all areas of the globe, revealed that 54.4% have a wildlife disease surveillance programme and 66% have implemented a strategy to manage disease spread. The lack of dedicated budget affected the possibility of outbreak investigations, sample collection and diagnostic testing. Although most Members maintain records relating to wildlife mortality or morbidity events in centralised databases, data analysis and disease risk assessment are reported as priority needs. The authors' evaluation of surveillance capacity found an overall low level, with marked variability among Members that was not restricted to a specific geographical area. Increased wildlife disease surveillance globally would help in understanding and managing risks to animal and public health. Moreover, consideration of the influence of socio-economic, cultural and biodiversity aspects could improve disease surveillance under a One Health approach.

L'émergence de maladies représente une menace pour la santé publique, l'économie et la conservation de la biodiversité au niveau mondial. La plupart des maladies émergentes sont d'origine animale et proviennent de la faune sauvage. Afin de prévenir leur propagation et de soutenir la mise en oeuvre de mesures de contrôle, une surveillance des maladies et des systèmes de notification sont nécessaires - et ce à l'échelle internationale, en raison de la mondialisation. En vue de définir les lacunes principales affectant les performances de la surveillance et de la notification sanitaire relative à la faune sauvage au niveau mondial, les auteurs ont analysé les données d'un questionnaire envoyé aux Points focaux nationaux de l'Organisation mondiale de la santé animale et traitant de la structure et des limites des systèmes de surveillance et de notification applicables à la faune sauvage sur leur territoire. Selon les réponses des 103 Membres, qui représentaient toutes les régions du monde, 54,4 % disposent d'un programme de surveillance et 66 % ont mis en oeuvre une stratégie visant à gérer la propagation de maladies. L'absence de budgets dédiés affecte la possibilité d'enquêter sur l'apparition d'épidémies, de prélever des échantillons et d'effectuer des tests diagnostiques. Bien que la majorité des Membres consignent dans des bases de données centralisées les événements de mortalité et de morbidité affectant la faune sauvage, l'analyse des données et l'évaluation des risques sanitaires ont été mentionnées comme étant des besoins prioritaires. Les auteurs ont évalué les capacités de surveillance qui se situent, selon eux, à un niveau faible et se caractérisent par une grande variabilité entre les Membres, indépendamment des zones géographiques dont il s'agit. Une meilleure surveillance sanitaire de la faune sauvage au niveau mondial permettrait d'améliorer la compréhension et la gestion des risques pour la santé animale et publique. Par ailleurs, une réflexion sur l'influence des aspects socio-économiques, culturels et liés à la biodiversité améliorerait la surveillance sanitaire mise en place dans le cadre de l'approche Une seule santé.

La aparición de enfermedades representa una amenaza de dimensión mundial para la salud pública, la economía y la conservación de los recursos biológicos. La mayor parte de las enfermedades zoonóticas tienen un origen animal, por lo general localizado en la fauna silvestre. Para evitar que estas enfermedades se propaguen y apoyar la aplicación de medidas de lucha hacen falta sistemas de vigilancia y notificación de enfermedades, sistemas que, teniendo en cuenta las dinámicas de la mundialización, deben declinarse a escala planetaria. Con objeto de determinar las principales carencias que lastran el buen funcionamiento de los sistemas de vigilancia y notificación de enfermedades de la fauna silvestre a escala mundial, los autores analizaron datos extraídos de un cuestionario distribuido entre los puntos focales nacionales de la Organización Mundial de Sanidad Animal, en el cual se les preguntaba por la estructura y los límites que presentaban en su territorio dichos sistemas. Las respuestas recibidas de 103 Miembros de todas las zonas del globo pusieron de relieve que un 54,4% de ellos cuenta con un programa de vigilancia sanitaria de la fauna silvestre y que un 66% tiene implantada una estrategia para contener la propagación de enfermedades. La falta de un presupuesto asignado específicamente a estas tareas limita la posibilidad de investigar eventuales brotes, obtener muestras y practicar pruebas de diagnóstico. Aunque la mayoría de los Miembros lleva un registro de los episodios de mortalidad y morbilidad de animales salvajes en bases de datos centralizadas, el análisis de datos y la determinación del riesgo de enfermedad son dos de los aspectos mencionados como necesidad prioritaria. La evaluación de la capacidad de vigilancia realizada por los autores puso de manifiesto un nivel en general bajo, con una marcada heterogeneidad entre los Miembros que no se circunscribía a una zona geográfica en particular. Una mayor vigilancia de las enfermedades de la fauna silvestre a escala mundial ayudaría a aprehender y manejar mejor los riesgos que estas presentan para la sanidad animal y la salud pública. Además, el hecho de tener en cuenta la influencia de factores socioeconómicos, culturales y ligados a la diversidad biológica podría traducirse en una más eficaz vigilancia sanitaria en clave de Una sola salud.

Integration of wildlife and environmental health into a One Health approach.

Climate change, habitat fragmentation and pollution, and subsequent loss of biodiversity and degradation of natural environments, threaten the range of ecosystem services that support all life on this planet. These changes, among others, are also driving the emergence of infectious diseases, with negative health outcomes for humans, animals, and our shared environment. Historically, interventions aimed at human and agricultural health issues did not always integrate wildlife or environmental health as part of the solution, which has resulted in unintended consequences. One Health recognises the interdependence of humans, animals and their shared environment, and provides a conceptual framework for developing interventions that optimise outcomes for human, animal and environmental health. However, there is a need to clearly articulate the core values, goals, and objectives of One Health for all relevant sectors in order to maximise synergies for communication, coordination, collaboration and, ultimately, for joint actions on disease control and prevention. The application of systems and harm reduction approaches, focusing on the socio-economic and environmental determinants of health, and ensuring good governance and effective leadership will also maximise the opportunities to develop 'win-win-win' solutions to global health and environmental challenges. These solutions would help propel One Health forward to reach its full potential and truly optimise health outcomes for all.

Le changement climatique, la fragmentation et la pollution des habitats, parallèlement à la perte de biodiversité et à la dégradation du milieu naturel qui en résultent constituent une menace pour le large éventail de services écosystémiques dont dépend la vie sur cette planète. Ces changements, parmi d'autres, favorisent également l'émergence des maladies infectieuses, avec des effets négatifs sur la santé des humains, des animaux et de leur environnement commun. Par le passé, les interventions en matière de santé humaine, végétale et animale (ces deux dernières dans le cadre des productions agricoles) ne prenaient pas toujours en compte la santé de la faune sauvage ni celle de l'environnement, ni leur rôle en tant qu'elles font partie des solutions recherchées, omission qui a vite entraîné d'importants effets indésirables. La méthode Une seule santé tient compte de l'interdépendance entre les humains, les animaux et leur environnement commun et fournit un cadre conceptuel pour la conception d'interventions dont les résultats seront ainsi les meilleurs possibles pour la santé tant humaine qu'animale et environnementale. Toutefois, il est nécessaire d'articuler clairement les valeurs, les objectifs et les résultats essentiels recherchés via Une seule santé par chacun des secteurs concernés, afin de maximiser les synergies en termes de communication, de coordination, de collaboration et, en définitive, d'activités communes pour le contrôle et la prévention des maladies. L'application de systèmes et d'approches d'atténuation des risques, axés sur les déterminants socio-économiques et environnementaux de la santé, ainsi que l'exercice d'une bonne gouvernance et d'un leadership efficace sont également des facteurs qui contribueront favorablement à la conception de solutions « gagnant-gagnant ¼ afin de résoudre les défis sanitaires et environnementaux mondiaux. Ces solutions pourraient donner une forte impulsion à la démarche Une seule santé, lui permettant de réaliser tout son potentiel et d'optimiser les bénéfices pour la santé de tous.

El cambio climático, la fragmentación y contaminación de los hábitats y su corolario, la pérdida de diversidad biológica y la degradación del medio natural, ponen en peligro toda la panoplia de servicios ecosistémicos que sostienen la vida en nuestro planeta. Estos cambios, entre otros, también están induciendo la aparición de enfermedades infecciosas que repercuten negativamente en la salud de personas, animales y el medio ambiente común a todos. Tradicionalmente, las intervenciones destinadas a abordar problemas sanitarios o agrícolas no siempre integraban la sanidad de la fauna silvestre y la salud ambiental como parte de la solución, lo que a veces tenía consecuencias imprevistas. La noción de Una sola salud, fundada en la realidad de la dependencia recíproca entre personas, animales y el medio ambiente común a todos ellos, ofrece un marco teórico desde el cual definir intervenciones que optimicen los resultados para la salud humana, animal y ambiental. No obstante, es necesario formular claramente los valores, fines y objetivos fundamentales de Una sola salud para todos los sectores afectados con objeto de lograr la máxima sinergia posible en materia de comunicación, coordinación, colaboración y, a la postre, acción conjunta de control y prevención de enfermedades. La aplicación de métodos sistémicos y de reducción de daños, que estén centrados en los determinantes socioeconómicos y ambientales de la salud y aseguren una gobernanza adecuada y un liderazgo eficaz, también ofrecerá un máximo de posibilidades de dar con soluciones que sean beneficiosas en las tres vertientes a la vez para responder a los problemas sanitarios y ambientales del mundo. Estas soluciones ayudarían a conferir impulso a la noción de Una sola salud para así poder extraer de ella el máximo provecho y optimizar realmente los resultados sanitarios en todos los frentes.

Natural Infections With Pigeon Paramyxovirus Serotype 1: Pathologic Changes in Eurasian Collared-Doves ( Streptopelia decaocto) and Rock Pigeons ( Columba livia) in the United States.

Pigeon paramyxovirus serotype 1 (PPMV-1) is a globally distributed, virulent member of the avian paramyxovirus serotype 1 serogroup that causes mortality in columbiformes and poultry. Following introduction into the United States in the mid-1980s, PPMV-1 rapidly spread causing numerous mortality events in Eurasian collared-doves ( Streptopelia decaocto) (ECDOs) and rock pigeons ( Columba livia) (ROPIs). The investigators reviewed pathological findings of 70 naturally infected, free-ranging columbiforms from 25 different mortality events in the United States. Immunohistochemistry targeting PPMV-1 nucleoprotein was used to determine the tissue distribution of the virus in a subset of 17 birds from 10 of the studied outbreaks. ECDOs (61 birds) and ROPIs (9 birds) were the only species in which PPMV-1-associated disease was confirmed by viral isolation and presence of histologic lesions. Acute to subacute tubulointerstitial nephritis and necrotizing pancreatitis were the most frequent histologic lesions, with immunolabeling of viral antigen in renal tubular epithelial cells and pancreatic acinar epithelium. Lymphoid depletion of bursa of Fabricius and spleen was common, but the presence of viral antigen in these organs was inconsistent among infected birds. Hepatocellular necrosis was occasionally present with immunolabeling of hypertrophic Kupffer cells, and immunopositive eosinophilic intracytoplasmic inclusion bodies were present in hepatocytes of 1 ECDO. Immunopositive lymphocytic choroiditis was present in 1 ECDO, while lymphocytic meningoencephalitis was frequent in ROPIs in absence of immunolabeling. This study demonstrates widespread presence of PPMV-1 antigen in association with histologic lesions, confirming the lethal potential of this virus in these particular bird species.

Widespread detection of highly pathogenic H5 influenza viruses in wild birds from the Pacific Flyway of the United States.

A novel highly pathogenic avian influenza virus belonging to the H5 clade 2.3.4.4 variant viruses was detected in North America in late 2014. Motivated by the identification of these viruses in domestic poultry in Canada, an intensive study was initiated to conduct highly pathogenic avian influenza surveillance in wild birds in the Pacific Flyway of the United States. A total of 4,729 hunter-harvested wild birds were sampled and highly pathogenic avian influenza virus was detected in 1.3% (n = 63). Three H5 clade 2.3.4.4 subtypes were isolated from wild birds, H5N2, H5N8, and H5N1, representing the wholly Eurasian lineage H5N8 and two novel reassortant viruses. Testing of 150 additional wild birds during avian morbidity and mortality investigations in Washington yielded 10 (6.7%) additional highly pathogenic avian influenza isolates (H5N8 = 3 and H5N2 = 7). The geographically widespread detection of these viruses in apparently healthy wild waterfowl suggest that the H5 clade 2.3.4.4 variant viruses may behave similarly in this taxonomic group whereby many waterfowl species are susceptible to infection but do not demonstrate obvious clinical disease. Despite these findings in wild waterfowl, mortality has been documented for some wild bird species and losses in US domestic poultry during the first half of 2015 were unprecedented.

TMEM106B regulates progranulin levels and the penetrance of FTLD in GRN mutation carriers.

OBJECTIVES: To determine whether TMEM106B single nucleotide polymorphisms (SNPs) are associated with frontotemporal lobar degeneration (FTLD) in patients with and without mutations in progranulin (GRN) and to determine whether TMEM106B modulates GRN expression. METHODS: We performed a case-control study of 3 SNPs in TMEM106B in 482 patients with clinical and 80 patients with pathologic FTLD-TAR DNA-binding protein 43 without GRN mutations, 78 patients with FTLD with GRN mutations, and 822 controls. Association analysis of TMEM106B with GRN plasma levels was performed in 1,013 controls and TMEM106B and GRN mRNA expression levels were correlated in peripheral blood samples from 33 patients with FTLD and 150 controls. RESULTS: In our complete FTLD patient cohort, nominal significance was identified for 2 TMEM106B SNPs (top SNP rs1990622, p(allelic) = 0.036). However, the most significant association with risk of FTLD was observed in the subgroup of GRN mutation carriers compared to controls (corrected p(allelic) = 0.0009), where there was a highly significant decrease in the frequency of homozygote carriers of the minor alleles of all TMEM106B SNPs (top SNP rs1990622, CC genotype frequency 2.6% vs 19.1%, corrected p(recessive) = 0.009). We further identified a significant association of TMEM106B SNPs with plasma GRN levels in controls (top SNP rs1990622, corrected p = 0.002) and in peripheral blood samples a highly significant correlation was observed between TMEM106B and GRN mRNA expression in patients with FTLD (r = -0.63, p = 7.7 × 10(-5)) and controls (r = -0.49, p = 2.2 × 10(-10)). CONCLUSIONS: In our study, TMEM106B SNPs significantly reduced the disease penetrance in patients with GRN mutations, potentially by modulating GRN levels. These findings hold promise for the development of future protective therapies for FTLD.

A combinatorial approach to screening carbon based materials for respiratory protection.

A combinatorial materials science approach for the discovery of an impregnated activated carbon that can adsorb a wide variety of toxic gases (i.e. a multi-gas carbon) has been developed. This approach presently allows for the parallel preparation and investigation of 64-100 IAC samples at once increasing the rate of discovery of viable multi-gas carbons. Multi-gas carbons were prepared using a solutions handling robot and screened gravimetrically for their effectiveness as gas adsorbents. The method was validated using known gas adsorbent materials such as ZnCl(2), K(2)CO(3) and CuO-impregnated carbons. The calculated adsorption capacities and stoichiometric ratios of reactions for these known gas adsorbent materials, when evaluated using the combinatorial approach, was comparable to the values obtained using traditional methods of analysis. A library of samples prepared by combining various amounts of CuO and ZnO impregnants showed the expected decreasing trend in the calculated stoichiometric ratio of reaction with respect to increasing amount of impregnants added. The method is now ready to use to explore new systems of impregnated activated carbons.

Forced swim test behavior in postpartum rats.

This study was undertaken to determine whether depression-like behavior can be observed in gonadally intact females that have experienced normal pregnancy. When tested on the forced swim test (FST) on postpartum days 1-7, previously pregnant rats spent slightly more time immobile, significantly less time swimming and diving, and defecated more than virgin controls. Subchronic treatment with nomifensine (DA reuptake inhibitor, 2.5mg/kg) but not sertraline (serotonin reuptake inhibitor, 10mg/kg) or desipramine (norepinephrine reuptake inhibitor, 10mg/kg) significantly decreased immobility on postpartum day 2. In rats pre-exposed to the FST in mid-pregnancy, neither subchronic nor chronic treatment with desipramine or sertraline decreased immobility on postpartum day 2; in contrast, chronic desipramine significantly decreased immobility in virgin controls. These results indicate that postpartum female rats, compared to virgin controls, show a reduction in some "active coping behaviors" but no significant increase in immobility when tested during the early postpartum period, unlike ovariectomized females that have undergone hormone-simulated pregnancy (HSP). Additionally, immobility that is increased by FST pre-exposure is not readily prevented by treatment with standard antidepressant medications in postpartum females. Depression-like behaviors previously observed in females that have undergone HSP may result from the more dramatic changes in estradiol, prolactin or corticosterone that occur during the early "postpartum" period, compared to the more subtle changes in these hormones that occur in actual postpartum females.

Eremophila glabra is an Australian plant that reduces lactic acid accumulation in an in vitro glucose challenge designed to simulate lactic acidosis in ruminants.

Lactic acidosis is a major welfare issue affecting animal health and production systems such as dairy and feedlot beef. We used two bioassays to identify bioactive plants of Australia with the potential to prevent acidosis in ruminants. In the first bioassay, a potentially acidotic environment was induced by adding glucose to rumen fluid and pH and gas production were used to estimate the effect on acid production and microbial fermentation after 5-h incubation. Australian plants (n = 104) were screened for their ability to prevent a decline in the pH without inhibiting normal gas production, and five plants namely Eremophila glabra, Kennedia eximia, Acacia saligna, Acacia decurrens and Kennedia prorepens with such properties were identified. We investigated further the two top ranking plants, E. glabra and K. prorepens, in the second bioassay to determine the extent of their effect in vitro, by extending the incubation to 24 h and measuring d-lactate, and volatile fatty acids (VFA) in addition to pH and gas production. These were measured at 0, 5, 10, 16 and 24 h after inoculation. Eremophila glabra maintained pH values that were higher and d-lactate concentrations that were lower than the control (P < 0.001), and comparable to the antibiotic-protected environment (AB; 12 µg of virginiamycin/ml). Eremophila glabra and AB treatments did not restrict fermentation, as judged by gas production and VFA. Kennedia prorepens slowed the decline in pH and reduced the accumulation of lactate but inhibited gas production. We concluded that, in vitro, E. glabra was effective at controlling events that can lead to acidosis and the effect was comparable to that of virginiamycin, while K. prorepens was less effective than E. glabra and also inhibited fermentation.

Microvascular free tissue transfer for gene delivery: in vivo evaluation of different routes of plasmid and adenoviral delivery.

Transfer of healthy autologous tissue as a microvascular free flap facilitates reconstruction during ablative cancer surgery. In addition to filling surgical defects, free flaps might concentrate viral vectors at the tumour bed and mediate local therapeutic effects. We evaluated the magnitude, topography and duration of luciferase gene expression after plasmid and adenoviral delivery in rat superficial inferior epigastric (SIE) flaps. For plasmid delivery, luciferase expression was significantly increased by all transduction routes (topical, intraflap injection, intravascular) (P<0.01) at day 1, but not at day 7. The spread of luciferase expression was significantly different between the 4 groups at 1 day (P=0.026) and was greatest for flaps transduced by intravascular injection. For adenoviral transduction, total radiance was significantly different between the transduced groups at 1, 14 and 28 days (P<0.05 for all comparisons). The highest levels of radiance were seen in the intravascular group. There was a statistically significant difference in the spread of light emission between the 3 groups at 1 (P=0.009) and 14 (P=0.013) days, but this was no longer evident at 28 days. Intravascular adenoviral delivery yields high-level, diffuse and durable gene expression in rat SIE flaps and is suitable for examination in therapeutic models.

Inflammatory tumour cell killing by oncolytic reovirus for the treatment of melanoma.

Reovirus is a promising unmodified double-stranded RNA (dsRNA) anti-cancer oncolytic virus, which is thought to specifically target cells with activated Ras. Although reovirus has been tested in a wide range of preclinical models and has entered early clinical trials, it has not previously been tested for the treatment of human melanoma. Here, we show that reovirus effectively kills and replicates in both human melanoma cell lines and freshly resected tumour; intratumoural injection also causes regression of melanoma in a xenograft in vivo model. Reovirus-induced melanoma death is blocked by caspase inhibition and is dependent on constituents of the Ras/RalGEF/p38 pathway. Reovirus melanoma killing is more potent than, and distinct from, chemotherapy or radiotherapy-induced cell death; a range of inflammatory cytokines and chemokines are released by infected tumour cells, while IL-10 secretion is abrogated. Furthermore, the inflammatory response generated by reovirus-infected tumour cells causes bystander toxicity against reovirus-resistant tumour cells and activates human myeloid dendritic cells (DC) in vitro. Hence, reovirus is suitable for clinical testing in melanoma, and may provide a useful danger signal to reverse the immunologically suppressive environment characteristic of this tumour.

Characterization of the adaptive and innate immune response to intravenous oncolytic reovirus (Dearing type 3) during a phase I clinical trial.

There is an emerging realization from animal models that the immune response may have both detrimental and beneficial therapeutic effects during cancer virotherapy. However, there is a dearth of clinical data on the immune response to viral agents in patients. During a recently completed phase I trial of intravenous reovirus type 3 Dearing (RT3D), heavily pretreated patients with advanced cancers received RT3D at doses escalating from 1 x 10(8) tissue culture infectious dose-50 (TCID(50)) on day 1 to 3 x 10(10) TCID(50) on 5 consecutive days of a 4 weekly cycle. A detailed analysis of the immune effects was conducted by collecting serial clinical samples for analysis of neutralizing anti-reoviral antibodies (NARA), peripheral blood mononuclear cells (PBMC) and cytokines. Significant increases in NARA were seen with peak endpoint titres >1/10 000 in all but one patient. The median fold increase was 250, with a range of 9-6437. PBMC subset analysis showed marked heterogeneity. At baseline, CD3+CD4+ T cells were reduced in most patients, but after RT3D therapy their numbers increased in 47.6% of patients. In contrast, most patients had high baseline CD3+CD8+ T-cell levels, with 33% showing incremental increases after therapy. In some patients, there was increased cytotoxic T-cell activation post-therapy, as shown by increased CD8+perforin/granzyme+ T-cell numbers. Most patients had high numbers of circulating CD3-CD56+ NK cells before therapy and in 28.6% this increased with treatment. Regulatory (CD3+CD4+CD25+) T cells were largely unaffected by the therapy. Combined Th1 and Th2 cytokine expression increased in 38% of patients. These data confirm that even heavily pretreated patients are capable of mounting dynamic immune responses during treatment with RT3D, although these responses are not clearly related to the administered virus dose. These data will provide the basis for future studies aiming to modulate the immune response during virotherapy.

Escherichia coli nitroreductase plus CB1954 enhances the effect of radiotherapy in vitro and in vivo.

Escherichia coli nitroreductase (NTR) converts the prodrug CB1954 (5-(aziridin-1-yl)-2,4-dinitrobenzamide) into a bifunctional alkylating agent that causes DNA crosslinks. In this study, the ability of NTR to enhance the combined effects of CB1954 and radiation has been tested in vitro and in vivo. Stably transduced ovarian cancer cells (SKOV3-NTR) that are sensitive to CB1954 (IC(50)=0.35 muM) demonstrated enhanced cytotoxicity when treated with CB1954 and single-fraction irradiation. The NTR-CB1954 system mediated a bystander effect in combination with radiation on transfer of conditioned medium from SKOV3-NTR, but not SKOV3, cells to SW480 target cells. The ability of CB1954 to enhance radiation-induced cytotoxicity in SKOV3-NTR (but not SKOV3) cells was also demonstrated by fluorescence-activated cell sorting (FACS) with dual staining for propidium iodide/fluorescein diacetate, 4',6-diamidino-2-phenylindole dichloride staining of apoptotic cells and measurement of double-stranded DNA breaks by FACS and confocal microscopy for gammaH2AX foci. Adenoviral delivery of NTR, under constitutive cytomegalovirus or tissue-specific CTP1 promoters, increased the in vitro cytotoxicity of CB1954 plus radiation in MTT and clonogenic assays. Finally, adenoviral delivery of NTR plus CB1954 enhanced the effect of fractionated radiotherapy (12 Gy in four fractions) in SW480 xenograft tumours in nude mice.

Combining radiation and cancer gene therapy: a potential marriage of physical and biological targeting?

The development and progression of cancer is marked by the acquisition of specific genetic hallmarks that endow tumour cells with a survival advantage over their normal tissue counterparts. In the process, tumours frequently develop resistance to radiotherapy and chemotherapy, and acquire the ability to evade the host immune response. Cancer gene therapy (CGT) represents an ideal therapeutic tool to target one or more of these underlying genetic abnormalities, and restore some form of order, to the otherwise autonomous and discordant microenvironment of the tumour. Most of the current research in CGT is aimed at its development as a novel form of targeted therapy that can be combined with other treatment modalities such as radiotherapy and chemotherapy. CGT may be integrated into radical chemoradiotherapy regimens, with the rationale of optimising the therapeutic index, through selective enhancement of radiosensitivity and cytotoxicity in tumour compared to normal tissues. CGT strategies have been developed that are aimed at enhancing the radiosensitivity of tissues by targeting angiogenesis, silencing abnormal cellular signalling, restoration of apoptosis, and promotion of immune detection and destruction of tumour cells. In addition, cytotoxic approaches such as virus directed enzyme prodrug therapy (VDEPT), genetic radionuclide therapy (GRANT) and oncolytic viral therapy have been combined with radiation to augment the cumulative tumour cell kill and overall therapeutic effect. In this article, we discuss various CGT strategies that have been investigated in combination with radiation. All the available preclinical and clinical evidence is reviewed with special emphasis on strategies that have already found their way into the clinic, or those with significant translational potential for the future.

Probing colloidal forces between a Si3N4 AFM tip and single nanoparticles of silica and alumina.

The atomic force microscope (AFM) has been used to measure surface forces between silicon nitride AFM tips and individual nanoparticles deposited on substrates in 10(-4) and 10(-2) M KCl solutions. Silica nanoparticles (10 nm diameter) were deposited on an alumina substrate and alumina particles (5 to 80 nm diameter) were deposited on a mica substrate using aqueous suspensions. Ionic concentrations and pH were used to manage attractive substrate-particle electrostatic forces. The AFM tip was located on deposited nanoparticles using an operator controlled offset to achieve stepwise tip movements. Nanoparticles were found to have a negligible effect on long-range tip-substrate interactions, however, the forces between the tip and nanoparticle were detectable at small separations. Exponentially increasing short-range repulsive forces, attributed to the hydration forces, were observed for silica nanoparticles. The effective range of hydration forces was found to be 2-3 nm with the decay length of 0.8-1.3 nm. These parameters are in a good agreement with the results reported for macroscopic surfaces of silica obtained using the surface force apparatus suggesting that hydration forces for the silica nanoparticles are similar to those for flat silica surfaces. Hydration forces were not observed for either alumina substrates or alumina nanoparticles in both 10(-4) M KCl solution at pH 6.5 and 10(-2) M KCl at pH 10.2. Instead, strong attractive forces between the silicon nitride tip and the alumina (nanoparticles and substrate) were observed.

Effect of a selective OX1R antagonist on food intake and body weight in two strains of rats that differ in susceptibility to dietary-induced obesity.

An orexin-1 receptor antagonist decreases food intake whereas orexin-A selectively induces hyperphagia to a high-fat diet. In the present study, we evaluated the effect of an orexin antagonist in two strains of rats that differ in their sensitivity to becoming obese while eating a high-fat diet. Male Osborne-Mendel (OM) and S5B/Pl (S5B) rats were treated acutely with an orexin-1 receptor antagonist (SB-334867), after adaptation to either a high-fat (56% fat energy) diet or a low-fat (10% fat energy) diet that were equicaloric for protein (24% energy). Ad libitum fed rats were injected intraperitoneally with SB-334867 at doses of 3, 10 or 30 mg/kg, or vehicle at the beginning of the dark cycle, and food intake and body weight were measured. Hypothalamic prepro-orexin and orexin-1 receptor mRNA expression were analyzed in OM and S5B rats fed at a high-fat or low-fat diet for two weeks. SB-334867 significantly decreased food intake in both strains of rats eating the high-fat diet but only in the OM rats eating the low fat diet. The effect was greatest at 12 and 24 h. Body weight was also reduced in OM rats 1d after injection of SB-334867 but not in the S5B rats. Prepro-orexin and orexin-1 receptor expression levels did not differ between strains or diets. These experiments demonstrate that an orexin antagonist (SB-334867) reduces food intake and has a greater effect in a rat strain that is susceptible to dietary-induced obesity, than in a resistant strain.

Most cases of dementia with hippocampal sclerosis may represent frontotemporal dementia.

Hippocampal sclerosis dementia (HSD) is a disease of unknown etiology and pathogenesis. To determine whether HSD cases could be reclassified as variants of frontotemporal dementia (FTD), a heterogeneous group of disorders, 18 brain autopsy cases previously diagnosed as HSD were re-evaluated. In 11 cases, ubiquitinated neuronal inclusions, similar to those of motor neuron disease inclusion dementia (MNDID), were found. Brain levels of soluble and insoluble tau were normal. Most patients with pathologic findings of HSD may actually have the MNDID variant of FTD.

Frontotemporal and motor neurone degeneration with neurofilament inclusion bodies: additional evidence for overlap between FTD and ALS.

We present the case of a patient who had clinical frontal lobe dementia without apparent motor neurone disease (MND), with pathologic findings not typical of any single currently classified frontotemporal degeneration (FTD). At autopsy, the brain had frontal and temporal atrophy with neuronal loss, gliosis, and superficial spongiosis, typical of all FTDs. There were at least three different morphologic types of intracytoplasmic neuronal inclusions in a variety of brain and brainstem regions, including the hippocampal dentate gyrus and pyramidal neurones, the neocortex (in particular, the motor cortex), basal ganglia, thalamus, subthalamic nucleus, basis pontis, and inferior olivary nuclei. Inclusions had the morphologies of Pick-like bodies, pleomorphic inclusions, and hyaline conglomerate (HC)-like inclusions. None of these were positive with tau immunostains. Pick-like bodies in the dentate gyrus were labelled with ubiquitin. The pleomorphic inclusions in the neocortex and dentate gyrus and the HC-like inclusions in the motor and parietal cortex were strongly positive with immunostains for neurofilament. We discuss the differential diagnosis and compare this case with those disorders to which it is most similar. In particular, we compare the unique neurofilament-positive inclusions to the inclusions of FTD-MND, to Pick bodies, and to the basophilic and HC inclusions that are occasionally seen in amytrophic lateral sclerosis (ALS). Although FTD-MND may be found in ALS, the findings in this case may have additional implications for a link between FTD and ALS.

Synapse loss is greater in presenile than senile onset Alzheimer disease: implications for the cognitive reserve hypothesis.

In the past, 'Alzheimer disease' (AD) referred to pathologic AD with clinical onset of dementia in the presenium, while 'senile dementia of the Alzheimer type' (SDAT) referred to senile onset AD. Because AD appears clinically homogeneous regardless of age of onset, the two subtypes in more recent years have not been distinguished. Pathologic differences have been noted, but synapse loss has not previously been compared between the two groups. Hypothesizing that synapse loss would be greater in presenile onset than senile onset AD, we compared synapse loss, as well as Alzheimer pathology in presenile and senile onset AD, using an ELISA method to quantify synaptophysin. Synaptophysin was significantly lower in presenile than senile AD in right frontal and bilateral parietal lobes. Neuritic plaque counts were significantly higher in presenile than senile AD in bilateral frontal and parietal lobes. Semi-quantitative evaluation of neurofibrillary tangles revealed significantly more tangles in bilateral frontal and parietal lobes in presenile than senile AD. Brain weight was significantly lower in presenile than senile AD. The differences in synapse loss and Alzheimer-type pathology in presenile and senile onset AD support the hypothesis that 'cognitive reserve' protects the human brain from neurodegenerative disease.

Structure of the yeast nucleosome core particle reveals fundamental changes in internucleosome interactions.

Chromatin is composed of nucleosomes, the universally repeating protein-DNA complex in eukaryotic cells. The crystal structure of the nucleosome core particle from Saccharomyces cerevisiae reveals that the structure and function of this fundamental complex is conserved between single-cell organisms and metazoans. Our results show that yeast nucleosomes are likely to be subtly destabilized as compared with nucleosomes from higher eukaryotes, consistent with the idea that much of the yeast genome remains constitutively open during much of its life cycle. Importantly, minor sequence variations lead to dramatic changes in the way in which nucleosomes pack against each other within the crystal lattice. This has important implications for our understanding of the formation of higher order chromatin structure and its modulation by post-translational modifications. Finally, the yeast nucleosome core particle provides a structural context by which to interpret genetic data obtained from yeast. Coordinates have been deposited with the Protein Data Bank under accession number 1ID3.

Contribution of asymmetric synapse loss to lateralizing clinical deficits in frontotemporal dementias.

BACKGROUND: Synapse loss has been found to be the major correlate of cognitive decline in Alzheimer disease (AD), and prefrontal synapse loss has been found in patients with frontotemporal dementia (FTD). OBJECTIVE: To see if our hypothesis that within each FTD case, regional synapse loss would correlate with lateralizing neuropsychologic and neurobehavioral deficits would be correct. DESIGN: We analyzed synaptophysin as a marker for synapse loss in snap-frozen brain samples, using an enzyme-linked immunosorbent assay technique. Quantitative results were obtained by comparing patient data with a standard curve made by analyzing serial dilutions of a recombinant synaptophysin protein fragment. A board-certified neuropsychologist and a board-certified neurologist, both unaware of the synaptophysin results, determined areas of primary neuropsychologic and neurobehavioral dysfunction. Relationships between areas of primary dysfunction and synapse loss were analyzed using the binomial test. PATIENTS: Six cases of FTD, 28 cases of AD, and 16 nondemented control subjects. RESULTS: Five of 6 FTD cases had regional synaptophysins correlating with lateralizing frontal or temporal deficits. Three of 6 correlated in 2 or more regions. Although our results were higher than that expected based on a pure-chance mechanism (50% vs 34%), statistical significance was not attained. CONCLUSIONS: We found a trend for an association between synapse loss and lateralizing neuropsychologic and neurobehavioral deficits in FTD. Studies in larger numbers of FTD cases are planned with the goal of attaining statistically significant conclusions.