Ethology - Volume 117, Issue 5 Page i - 471

Long‐tailed cuckoo, Urodynamis taitensis, uses mimetic begging calls to solicit food from host whiteheads, Mohoua albicilla, in New Zealand. Photo reproduced by permission of Tim Lovegrove. (page i)

Article first published online: 5 APR 2011 | DOI: 10.1111/j.1439-0310.2011.01903.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01903.x/abstract)

* Research Papers

Past and Present Risk: Exposure to Predator Chemical Cues Before and after Metamorphosis Influences Juvenile Wood Frog Behavior (pages 367–373)

Tina Barbasch and Michael F. Benard

Article first published online: 9 MAR 2011 | DOI: 10.1111/j.1439-0310.2011.01885.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01885.x/abstract)

Parental Alarm Calls of the White‐Crowned Sparrow Fail to Stimulate Corticosterone Production in Nest‐Bound Offspring (pages 374–384)

James W. Rivers, Lynn B. Martin, Andrea L. Liebl and Matthew G. Betts

Article first published online: 23 FEB 2011 | DOI: 10.1111/j.1439-0310.2011.01883.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01883.x/abstract)

Acoustic Monitoring Reveals Congruent Patterns of Territorial Singing Behaviour in Male and Female Tropical Wrens (pages 385–394)

Anneka E. Osmun and Daniel J. Mennill

Article first published online: 28 MAR 2011 | DOI: 10.1111/j.1439-0310.2011.01887.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01887.x/abstract)

When the Whites of the Eyes are Red: A Uniquely Human Cue (pages 395–399)

Robert R. Provine, Marcello O. Cabrera, Nicole W. Brocato and Kurt A. Krosnowski

Article first published online: 24 MAR 2011 | DOI: 10.1111/j.1439-0310.2011.01888.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01888.x/abstract)

Simulated Predation Risk Influences Female Choice in Túngara Frogs, Physalaemus pustulosus (pages 400–407)

Luis A. Bonachea and Michael J. Ryan

Article first published online: 16 MAR 2011 | DOI: 10.1111/j.1439-0310.2011.01889.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01889.x/abstract)

The Function of the Four Types of Waving Display in Uca lactea: Effects of Audience, Sand Structure, and Body Size (pages 408–415)

Daisuke Muramatsu

Article first published online: 1 MAR 2011 | DOI: 10.1111/j.1439-0310.2011.01884.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01884.x/abstract)

Poor Nutritional Conditions During the Early Larval Stage Reduce Risk‐Taking Activities of Fire Salamander Larvae (Salamandra salamandra) (pages 416–421)

E. Tobias Krause, Sebastian Steinfartz and Barbara A. Caspers

Article first published online: 7 MAR 2011 | DOI: 10.1111/j.1439-0310.2011.01886.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01886.x/abstract)

Validation of a Method for Quantifying Male Mating Preferences in the Guppy (Poecilia reticulata) (pages 422–429)

Sarah B. Jeswiet and Jean‐Guy J. Godin

Article first published online: 21 MAR 2011 | DOI: 10.1111/j.1439-0310.2011.01891.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01891.x/abstract)

Kangaroo Rats Remodel Burrows in Response to Seasonal Changes in Environmental Conditions (pages 430–439)

Andrew J. Edelman

Article first published online: 16 MAR 2011 | DOI: 10.1111/j.1439-0310.2011.01890.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01890.x/abstract)

The Influence of Age on Male Mate‐Searching Behaviour in Thornbug Treehoppers (pages 440–450)

Paul A. De Luca and Reginald B. Cocroft

Article first published online: 16 MAR 2011 | DOI: 10.1111/j.1439-0310.2011.01893.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01893.x/abstract)

Effects of Paternal Reproductive Tactic on Juvenile Behaviour and Kin Recognition in Chinook Salmon (Oncorhynchus tshawytscha) (pages 451–458)

Adam J. Henkel, Shawn R. Garner and Bryan D. Neff

Article first published online: 17 MAR 2011 | DOI: 10.1111/j.1439-0310.2011.01894.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01894.x/abstract)

Age and Behavior of Honey Bee Workers, Apis mellifera, that Interact with Drones (pages 459–468)

Tyler L. Stout, Jeremy D. Slone and Stanley S. Schneider

Article first published online: 22 MAR 2011 | DOI: 10.1111/j.1439-0310.2011.01895.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01895.x/abstract)

* Obituary

Günter Tembrock – a Pioneer of Behavioural Biology Who Understood the Language of Animals (pages 469–471)

Andreas Wessel

Article first published online: 5 APR 2011 | DOI: 10.1111/j.1439-0310.2011.01904.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0310.2011.01904.x/abstract)

Journal of Animal Physiology and Animal Nutrition - June 2011 Volume 95, Issue 3 Pages 273–408

Original articles

Comparison of grass haylage digestibility and metabolic plasma profile in Icelandic and Standardbred horses (pages 273–279)

S. Ragnarsson and A. Jansson

Article first published online: 26 AUG 2010 | DOI: 10.1111/j.1439-0396.2010.01049.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01049.x/abstract)

Expression of GPR30 and GPR43 in oral tissues: deriving new hypotheses on the role of diet in animal physiology and the development of oral cancers (pages 280–285)

M. Mau, M. Mielenz, K‐H. Südekum and A. G. Obukhov

Article first published online: 29 SEP 2010 | DOI: 10.1111/j.1439-0396.2010.01052.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01052.x/abstract)

Effect of conditioning horses every third day at v10 on measures of fitness (pages 286–293)

A. Lindner, R. A. López, E. Durante, H. Hernandez, V. Botta, S. Sadaba and F. M. Boffi

Article first published online: 29 SEP 2010 | DOI: 10.1111/j.1439-0396.2010.01053.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01053.x/abstract)

Effect of bee pollen levels on productive, reproductive and blood traits of NZW rabbits (pages 294–303)

Y. A. Attia, A. Al‐Hanoun, A. E. Tag El‐ Din, F. Bovera and Y. E. Shewika

Article first published online: 29 SEP 2010 | DOI: 10.1111/j.1439-0396.2010.01054.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01054.x/abstract)

Effect of condensed tannin ingestion in sheep and goat parotid saliva proteome (pages 304–312)

E. Lamy, G. da Costa, R. Santos, F. Capela e Silva, J. Potes, A. Pereira, A. V. Coelho and E. Sales Baptista

Article first published online: 29 SEP 2010 | DOI: 10.1111/j.1439-0396.2010.01055.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01055.x/abstract)

The effect of replacing corn with glycerol on ruminal bacteria in continuous culture fermenters (pages 313–319)

A. A. AbuGhazaleh, S. Abo El‐Nor and S. A. Ibrahim

Article first published online: 29 SEP 2010 | DOI: 10.1111/j.1439-0396.2010.01056.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01056.x/abstract)

Effect of dietary Ulva and Spirulina on weight loss and body composition of rainbow trout, Oncorhynchus mykiss (Walbaum), during a starvation period (pages 320–327)

D. Güroy, B. Güroy, D. L. Merrifield, S. Ergün, A. A. Tekinay and M. Yiğit

Article first published online: 29 SEP 2010 | DOI: 10.1111/j.1439-0396.2010.01057.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01057.x/abstract)

Phagocytic activity in blood and proliferation of peripheral blood lymphocytes during the perinatal period in primiparous sows (pages 328–334)

B. Jakovac‐Strajn, A. Ihan, A. N. Kopitar and T. Malovrh

Article first published online: 29 SEP 2010 | DOI: 10.1111/j.1439-0396.2010.01058.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01058.x/abstract)

Effect of inulin and oligofructose enrichment of the diet on rats suffering thiamine deficiency (pages 335–342)

B. Dębski, T. Kurył, M. A. Gralak, J. Pierzynowska and M. Drywień

Article first published online: 29 SEP 2010 | DOI: 10.1111/j.1439-0396.2010.01059.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01059.x/abstract)

Effects of dietary vitamin E on immunological stress of layers and their offspring (pages 343–350)

G. P. Zhao, M. J. Han, M. Q. Zheng, J. P. Zhao, J. L. Chen and J. Wen

Article first published online: 29 SEP 2010 | DOI: 10.1111/j.1439-0396.2010.01060.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01060.x/abstract)

Effects of non‐antibiotic feed additives on performance, tibial dyschondroplasia incidence and tibia characteristics of broilers fed low‐calcium diets (pages 351–358)

M. Houshmand, K. Azhar, I. Zulkifli, M. H. Bejo, A. Meimandipour and A. Kamyab

Article first published online: 12 DEC 2010 | DOI: 10.1111/j.1439-0396.2010.01061.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01061.x/abstract)

Influence of a high‐protein diet on energy balance in obese cats allowed ad libitum access to food (pages 359–367)

A. Wei, A. J. Fascetti, K. J. Liu, C. Villaverde, A. S. Green, E. G. Manzanilla, P. J. Havel and J. J. Ramsey

Article first published online: 29 OCT 2010 | DOI: 10.1111/j.1439-0396.2010.01062.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01062.x/abstract)

Imprecision when using measuring cups to weigh out extruded dry kibbled food (pages 368–373)

A. J. German, S. L. Holden, S. L. Mason, C. Bryner, C. Bouldoires, P. J. Morris, M. Deboise and V. Biourge

Article first published online: 29 OCT 2010 | DOI: 10.1111/j.1439-0396.2010.01063.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01063.x/abstract)

Effect of macroalgae enriched with microelements on egg quality parameters and mineral content of eggs, eggshell, blood, feathers and droppings (pages 374–387)

I. Michalak, K. Chojnacka, Z. Dobrzański, H. Górecki, A. Zielińska, M. Korczyński and S. Opaliński

Article first published online: 29 OCT 2010 | DOI: 10.1111/j.1439-0396.2010.01065.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01065.x/abstract)

Black tea reduces diarrhoea prevalence but decreases growth performance in enterotoxigenic Escherichia coli‐infected post‐weaning piglets (pages 388–398)

M. J. Bruins, M. A. M. Vente‐Spreeuwenberg, C. H. Smits and L. G. J. Frenken

Article first published online: 29 OCT 2010 | DOI: 10.1111/j.1439-0396.2010.01066.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01066.x/abstract)

The effects of increasing water content to reduce the energy density of the diet on body mass changes following caloric restriction in domestic cats (pages 399–408)

K. M. Cameron, P. J. Morris, R. M. Hackett and J. R. Speakman

Article first published online: 28 DEC 2010 | DOI: 10.1111/j.1439-0396.2010.01107.x

(http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2010.01107.x/abstract)

Jornalismo científico: uma atividade em crise?

Nos últimos anos, o declínio da popularidade dos jornais impressos e o sucesso da internet como fonte de informações geraram debates sobre uma suposta crise do jornalismo no Estados Unidos e na Europa. Esse sentimento de crise preocupa também profissionais do jornalismo científico.

Na próxima segunda-feira, dia 11 de abril, às 10 horas, Martin W Bauer, professor da London School of Economics, virá ao Museu da Vida para debater o assunto. A palestra faz parte da programação dos “Seminários em Divulgação Científica”, do curso de Especialização em Divulgação da Ciência, da Tecnologia e da Saúde.

O palestrante apresentará os resultados de estudos recentemente realizados com jornalistas científicos de diferentes partes do mundo, sobretudo Reino Unido e Brasil. As pesquisas buscaram avaliar o sentimento de crise nessa categoria profissional e identificar suas principais causas. Embora ainda não esteja claro se realmente existe uma crise de caráter local ou global, algumas preocupações foram apontadas, como a falta de equilíbrio entre a reportagem independente e a replicação de materiais de assessorias de imprensa.

Bauer é professor do Instituto de Psicologia Social e Metodologia de Pesquisa na London School of Economics, onde dirige também o curso de mestrado em Comunicação Social e Pública, e edita a revista Public Understanding of Science. Além disso, é autor de vários livros e artigos na área de jornalismo e divulgação científica.

O seminário, em português, é gratuito e aberto ao público. Não é necessária inscrição prévia.

Seminário: “A Crisis of Science Journalism?”

Por Martin W Bauer (London School of Economics)

Data e horário: Segunda-feira, 11 de abril, às 10h

Local: Tenda da Ciência, no campus da Fiocruz (Av. Brasil, 4.365, Manguinhos, Rio de Janeiro

Casa de Oswaldo Cruz| COC| Fiocruz

Comunicação: Edna Padrão

Leia esta e outras notícias na Intranet Fiocruz: http://intranet.fiocruz.br

Envie sua sugestão ou comentários: divulgacao@coc.fiocruz.br | tel: 55 (21) 3865-2276

Fiocruz inaugura Casa Eficiente no campus de Manguinhos

Estrutura apresenta ao público geral alternativas para economizar água e energia

Cuidar do meio ambiente – condição necessária para garantir a saúde e a qualidade de vida da população – é compromisso da Fundação Oswaldo Cruz (Fiocruz). E este compromisso foi reafirmado hoje, Dia Mundial da Saúde (7/4), quando a Fundação inaugurou a Casa Eficiente, um local destinado à experimentação e à demonstração de alternativas para uso racional de água e energia. A Casa Eficiente da Fiocruz surgiu como uma espécie de laboratório, onde soluções de engenharia e arquitetura pudessem ser testadas em escala piloto para, depois, serem estendidas a toda a Fundação. Esse objetivo, entretanto, foi ampliado e, hoje, a casa é um espaço de educação ambiental, visando divulgar para o público geral alternativas ecologicamente corretas. Desde o lado de fora, os visitantes já podem constatar os diferenciais da casa, toda feita de madeira certificada de reflorestamento. Também é possível observar três caixas d’água: uma convencional, uma ligada a um sistema que coleta água da chuva e outra acoplada a um aquecedor solar feito de garrafa pet.

O aquecedor é um sistema fechado, que funciona como uma estufa de garrafa pet, para não perder energia, e contém embalagens tetrapack pintadas de preto, para absorver ao máximo o calor do sol. Como a água fria é mais pesada e desce e a água quente é mais leve e sobe, o líquido circula pelo aquecedor e vai esquentando. O resultado é percebido no banheiro da casa, onde – ao lado da descarga que usa água da chuva – o chuveiro pode ter água quente sem consumir eletricidade. “Mesmo que o morador queira tomar um banho bem quente, ele economiza energia. Sem o aquecedor solar, ele teria que colocar o chuveiro elétrico no modo “inverno”. Aproveitando a energia solar, ele já alcança a temperatura desejada no modo “verão”, que consome menos energia”, explica o engenheiro Tatsuo Shubo, coordenador da área de infraestrutura e ambiente da Diretoria de Administração do Campus (Dirac/Fiocruz).

Na casa também é possível visualizar as diferenças entre uma torneira convencional, na qual o fluxo de água só é interrompido se alguém fechar, e duas planejadas para desligar automaticamente, sendo uma por sistema mecânico e a outra eletrônica. As duas últimas representam uma enorme economia de água em relação à primeira. A torneira eletrônica, contudo, é ainda mais eficiente. “Ela libera exatamente o mesmo volume de água a cada vez que é acionada, enquanto o sistema mecânico é irregular”, afirma Tatsuo. Além das torneiras, os visitantes podem comparar a eficiência de diferentes aparelhos de ar condicionado. Embora, na aparência, eles sejam semelhantes, o modelo de classe A consome menos energia para resfriar o ambiente, se comparado ao modelo de classe C.

As lâmpadas – várias delas instaladas num painel – também reservam surpresas. As mais finas são as que mais iluminam e com um gasto inferior de energia. “A Fiocruz firmou uma parceria com a Light para substituir todas as lâmpadas da Fundação pelas mais eficientes, o que vai gerar uma economia de R$ 3 milhões por ano”, calcula o engenheiro. Experimentando, na prática, os visitantes constatam que, além da lâmpada, o tipo de luminária e a cor das paredes também determinam a eficiência da iluminação. Outra curiosidade encontrada na casa é a lâmpada RGB, que, por controle remoto, varia gradualmente sua temperatura de cor ou, em outras palavras, simula com perfeição a mudança do dia para a noite. Por isso, ela é uma ferramenta útil em pesquisas que requerem o desenvolvimento de animais e plantas em laboratório.

Cientistas brasileiros criam nervo artificial

O nervo artificial receberá 18 fatores de crescimento - substâncias sintetizadas, fabricadas pelo organismo, que proporcionam o desenvolvimento de um determinado tecido (osso, pele e nervo) e estimulam a reparação dos mesmos. 

Regeneração motora

Pesquisadores da PUC do Rio Grande do Sul, em parceria com a Universidade Montpellier, na França, criaram o protótipo de um nervo artificial, um sonho antigo na área médica.

O objetivo é criar um material absorvível pelo organismo que regenere o nervo periférico (fora da coluna vertebral) rompido por algum acidente ou trauma.

Experimentos com animais apontam uma recuperação funcional bastante adequada do ponto de vista motor e sensitivo.

Nervo artificial

Para construir o nervo artificial, os pesquisadores se inspiraram no nervo humano. A sua regeneração depende de nutrientes. "A dificuldade é a liberação gradual das substâncias, conforme as necessidades de cada etapa da recuperação", explica o Dr. Jefferson Braga Silva, coordenador da pesquisa.

O nervo artificial receberá, a princípio, 18 fatores de crescimento - substâncias sintetizadas, fabricadas pelo organismo, que proporcionam o desenvolvimento de um determinado tecido (osso, pele e nervo) e estimulam a reparação dos mesmos.

A ideia é utilizar a nanotecnologia, que envolve a construção de uma esfera em escala nanométrica, que carregue as substâncias até o ponto onde elas são necessárias e podem ser absorvidas.

De um tubo de silicone ao nervo artificial

Jefferson Braga trabalha no projeto desde 1995, unindo a clínica à investigação científica. Ele começou com um tubo de silicone, que passou a utilizar nas microcirurgias reconstrutivas.

Dez anos depois, agregou células-tronco à tecnologia, conquistando melhores resultados. As 28 pessoas submetidas à técnica até agora recuperaram a capacidade funcional, sensibilidade e motricidade.

As células-tronco utilizadas são retiradas da medula óssea dos próprios pacientes. Imaturas, elas não têm forma nem função definidas, apresentando grande capacidade de proliferação e de originar diferentes tipos celulares.

O cirurgião ainda está insatisfeito e se questiona de que forma poderá aumentar a recuperação funcional dos pacientes.

Falta de tecnologia

Outra questão é a falta de acesso à tecnologia. "Acredito que a universalização depende de uma tecnologia acessível, barata e de fácil utilização."

Segundo ele, mais do que falta de recursos, o País carece de pessoal especializado. "Precisamos ter algo que possa ser usado do Oiapoque ao Chuí, passando por Porto Alegre", comenta. O mais comum atualmente é que os cirurgiões realizem enxertos, retirando da perna para recolocar na parte afetada.

De Montpellier, participam da pesquisa as Faculdades francesas de Química, Medicina, Engenharia, Física e Eletrônica, além de duas empresas ligadas à universidade e duas suíças das áreas de nanotecnologia, equipamentos biomédicos e de engenharia de materiais.

Jefferson Braga relata que a falta de assistência em países em desenvolvimento faz muitos pacientes chegarem para cirurgia depois que o nervo já está retraído. "[No exterior,] os traumas e sequelas são menores porque quem se machuca se opera em três dias."

Testes do nervo artificial

Os exames clínicos com o nervo artificial envolverão 20 centros pelo mundo em países como Brasil (com os testes na PUCRS), França, Suíça e EUA.

Cada instituição selecionará 20 voluntários, seguindo critérios ainda a serem definidos. No total, haverá 400 participantes que indicarão se o nervo artificial poderá ser usado em larga escala.

"Disso dependem fatores como valores acessíveis, simplicidade e resultados satisfatórios", pondera o médico. Com a evolução, o projeto deverá gerar depósito de patente e impactará outras iniciativas. "Se criarmos o nervo artificial da forma como estamos realizando, abriremos uma porta enorme para as pesquisas em lesões de pele, ossos e cartilagens", projeta Jefferson Braga.

Fatty Liver: How a Serious Problem Arises

ScienceDaily (Apr. 6, 2011) — Excess fat around the hips and belly may not really be compatible with current beauty ideals, but, to a certain degree, it is a normal, even vital energy store of our body. However, it is a different matter if the organism stores fat in organs such as the liver, pancreas or muscles. This is a clear sign of a metabolic disorder.

3D-illustration of a human liver with blood vessels (red and blue) and bile duct (green). 

Up to 80 percent of obese people develop fatty liver disease, which is regarded a typical characteristic of the dangerous metabolic syndrome. Deposition of fat in the liver may lead to chronic liver inflammation and even to liver cancer. In addition, fatty liver is considered to be an independent risk factor for coronary heart disease and atherosclerosis.

The great medical relevance of fatty liver as a severe condition accompanying insulin resistance and type II diabetes caused the research group headed by Dr. Stephan Herzig of the Division of Molecular Metabolic Control to investigate how this syndrome arises. Which molecular switches are turned on or off in a cell when food delivers too much energy-rich fat molecules, or triglycerides?

To this end, the investigators determined the level of particular proteins involved in specific gene activation in the liver tissue of mice. These proteins, which are known as transcriptional co-activators, regulate which proteins are read and transcribed into messenger RNA molecules in a cell. In overweight mice, the researchers observed that a high triglyceride level in the liver was always associated with reduced production of a co-activator called TBL1. This was found both in animals that developed fatty liver for hereditary reasons and in those animals that received calorie-rich food.

TBL1 was originally discovered in connection with a rare hereditary hearing disorder. In the liver, but not in other tissues, an oversupply of fat reduces the production of TBL1. As a result, fat burning in the liver is reduced so that more fat molecules are deposited in liver cells. "This, in turn, may lead to a further reduction of TBL1," says Stephan Herzig.

Not only in mice is TBL1 linked to the liver fat (lipid) metabolism. The group found the same pattern in human liver tissue samples: the higher their triglyceride levels, the lower their TBL1 levels.

Stephan Herzig expects a practical use of these results. "We might be able in the future to use TBL1 levels for identifying those obese persons who have a special risk of developing fatty liver. We could then give specific dietary recommendations to counteract this."

Simple Chemical Cocktail Shows First Promise for Limb Re-Growth in Mammals

ScienceDaily (Apr. 6, 2011) — Move over, newts and salamanders. The mouse may join you as the only animal that can re-grow their own severed limbs. Researchers are reporting that a simple chemical cocktail can coax mouse muscle fibers to become the kinds of cells found in the first stages of a regenerating limb. Their study, the first demonstration that mammal muscle can be turned into the biological raw material for a new limb, appears in the journalACS Chemical Biology.

Newt. Just as injured newts can sprout new limbs, a simple chemical cocktail shows promise for limb re-growth in mammals. It nudges mouse cells on a path toward regeneration.

Darren R. Williams and Da-Woon Jung say their "relatively simple, gentle, and reversible" methods for creating the early stages of limb regeneration in mouse cells "have implications for both regenerative medicine and stem cell biology." In the future, they suggest, the chemicals they use could speed wound healing by providing new cells at the injured site before the wound closes or becomes infected. Their methods might also shed light on new ways to switch adult cells into the all-purpose, so-called "pluripotent," stem cells with the potential for growing into any type of tissue in the body.

The scientists describe the chemical cocktail that they developed and used to turn mouse muscle fibers into muscle cells. Williams and Jung then converted the muscle cells turned into fat and bone cells. Those transformations were remarkably similar to the initial processes that occur in the tissue of newts and salamanders that is starting to regrow severed limbs.

Structure Formed by Strep Protein Can Trigger Toxic Shock

ScienceDaily (Apr. 6, 2011) — Infection with some strains of strep turn deadly when a protein found on their surface triggers a widespread inflammatory reaction. In a report published April 7 in the journalNature, researchers describe the precise architecture of a superstructure formed when the bacterial protein called M1 links with a host protein, fibrinogen, that is normally involved in clotting blood.

M1 joints (red) and fibrinogen struts (green) form a scaffold. Dense assemblies trigger a pathological response that can lead to toxic shock.

The proteins form scaffolds with M1 joints and fibrinogen struts that assemble into dense superstructures. Frontline immune cells called neutrophils mistake these thick networks for blood clots and overreact, releasing a chemical signal that can dilate vessels to the point where they leak, the team reports.

"We knew that M1 plus fibrinogen was inflammatory, but how was unknown. By determining the structure of this complex, we were able to identify the characteristics that lead to a sepsis response," said Partho Ghosh, Ph.D., professor of chemistry and biochemistry at the University of California, San Diego who studies the structure of virulence factors and led this project.

Ghosh and colleagues found that the density of the M1-fibrinogen structure was a critical characteristic. Looser structures or separate fibers formed by altered versions of M1 failed to trigger a pathological response.

"This research provides the first snapshot of the interaction between this key bacterial virulence factor and its human target at the atomic level," said Victor Nizet, M.D., professor of pediatrics and pharmacy and a co-author of the report.

Difficult to treat once they set in, the leaking blood vessels and organ failure of strep-induced toxic shock prove fatal for 30 percent of patients. Ghosh and Nizet have a long-standing collaboration aimed at designing treatments to counteract the toxic effects of strep protein.

Additional co-authors include Pauline Macheboeuf and Cosmo Buffalo of the department of chemistry and biochemistry, Annelies Zinkernagel and Jason Cole of the department of pediatrics, and Chi-yu Fu and Jack Johnson of The Scripps Research Institute. The National Institutes of Health funded this work.

Chemical Engineers Have Designed Molecular Probe to Study Disease

ScienceDaily (Apr. 6, 2011) — (Santa Barbara, Calif.) -- Chemical engineers at UC Santa Barbara expect that their new process to create molecular probes may eventually result in the development of new drugs to treat cancer and other illnesses.

This shows enhanced detection of endogenous protease activity. 

Their work, reported in the journalChemistry & Biology, describes a new strategy to build molecular probes to visualize, measure, and learn about the activities of enzymes, called proteases, on the surface of cancer cells.

Patrick Daugherty, senior author and professor of chemical engineering at UCSB, explained that the probes are effective at understanding proteases involved in tumor metastasis.

"Tumor metastasis is widely regarded as the cause of death for cancer patients," said Daugherty. "It's not usually the primary tumor that causes death. Metastasis is mediated by proteases, like the one we are studying here. These proteases can enable tumor cells to separate and degrade surrounding tissue, and then migrate to sites distant from the primary tumor. The tumor doesn't just fall apart. There are many events that must occur for a tumor to release cancerous cells into the blood stream that can circulate and end up in other tissues such as liver or bone."

The probes allowed the researchers, for the first time, to measure directly the activity of a protease involved in metastasis. They did this by adding their probe into a dish of tumor cells. They then measured the activity of this protease that breaks down collagen -- the single most abundant protein (by mass) in the human body.

"We have immediate plans to use similar probes to effectively distinguish metastatic HER2 positive tumors, one of the most commonly used biomarkers of breast cancer," said Daugherty. "A significant fraction of patients have HER2 positive tumors but we don't know which of those tumors is going to metastasize yet. But our ability to make these probes can allow us to identify which of those HER2 positive tumors have the ability to break down that surrounding tissue, to detach from the primary tumor, and to establish a separate tumor somewhere else in the body."

The authors designed the molecular probe to be recognized by a single protease rather than by the many proteases that are present in human tissues. That is half of the probe. The other half of the probe involves an optical technique used to measure activity. This approach relies upon the use of two engineered fluorescent proteins, derived from marine organisms, that absorb and emit light in a process called FRET, or Forster resonance energy transfer.

To prepare the probes, the researchers introduced a gene that encodes the probe into the bacteria E. coli. Then they produced and purified significant quantities of the probe. All of the information needed for the probe is encoded by a DNA sequence. The probes are easy and inexpensive to produce, as well as easily shared with other researchers.

In addition to studying cancer, similarly constructed probes have ramifications for studying Alzheimer's disease, arthritis and connective tissue diseases, bacterial infections, viruses, and many other diseases.

"The fact that you can generalize the concept, and the way you make these probes, to many systems, makes it attractive," said Daugherty. "We happen to study the activity of this protease and a certain type of tumor cells that are derived from cancer patients. But you could apply this to hundreds of molecules and really develop a working understanding of how groups of proteases function together in cell biology."

In individuals with rheumatoid arthritis, for example, there is increased production of proteases, including the one studied by Daugherty's team. This protease mediates collagen breakdown and joint destruction. "If you've got an enzyme that can chew up collagen and you've got lots of collagen in your joints, then you would expect that you would see more rapid degradation of the joint by those proteases," said Daugherty.

Daugherty's research group has created approximately 25 probes analogous to the one presented in the paper. They are building a panel of about 100 probes and will use this panel to characterize how different proteases function. This investigation could lead to new drug therapies for a variety of diseases.

The first author on the paper is Daugherty's former graduate student, Abeer Jabaiah, who is applying a similar process to another protease involved in tumor metastasis as a postdoctoral fellow in Daugherty's lab. Funding for this work was provided by the National Institutes of Health through the National Cancer Institute's Center of Cancer Nanotechnology Excellence and the National Heart, Lung, and Blood Institute's Program of Excellence in Nanotechnology.

Scientists Develop New Technology for Stroke Rehabilitation

ScienceDaily (Apr. 6, 2011) — Devices which could be used to rehabilitate the arms and hands of people who have experienced a stroke have been developed by researchers at the University of Southampton.

The new technologies will help patient rehabilitation. 

In a paper to be presented this week (6 April) at the Institution of Engineering and Technology (IET) Assisted Living Conference, Dr Geoff Merrett, a lecturer in electronic systems and devices, will describe the design and evaluation of three technologies which could help people who are affected by stroke to regain movement in their hand and arm.

Dr Merrett worked with Dr Sara Demain, a lecturer in physiotherapy and Dr Cheryl Metcalf, a researcher in electronic systems and devices, to develop three 'tactile' devices which generate a realistic 'sense of touch' and sensation -- mimicking those involved in everyday activities.

Dr Demain says: "Most stroke rehabilitation systems ignore the role of sensation and they only allow people repetitive movement. Our aim is to develop technology which provides people with a sense of holding something or of feeling something, like, for example, holding a hot cup of tea, and we want to integrate this with improving motor function."

Three tactile devices were developed and tested on patients who had had a stroke and on healthy participants. The devices were: a 'vibration' tactile device, which users felt provided a good indication of touch but did not really feel as if they were holding anything; a 'motor-driven squeezer' device, which users said felt like they were holding something, a bit like catching a ball; and a 'shape memory alloy' device which has thermal properties and creates a sensation like picking up a cup of tea.

Dr Merrett adds: "We now have a number of technologies, which we can use to develop sensation. This technology can be used on its own as a stand-alone system to help with sensory rehabilitation or it could be used alongside existing health technologies such as rehabilitation robots or gaming technologies which help patient rehabilitation."