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1.
Osteoarthritis Cartilage ; 21(2): 269-78, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23159952

RESUMO

OBJECTIVE: Increasing evidence points to a strong genetic component to osteoarthritis (OA) and that certain changes that occur in osteoarthritic cartilage recapitulate the developmental process of endochondral ossification. As zebrafish are a well validated model for genetic studies and developmental biology, our objective was to establish the spatiotemporal expression pattern of a number of OA susceptibility genes in the larval zebrafish providing a platform for functional studies into the role of these genes in OA. DESIGN: We identified the zebrafish homologues for Mcf2l, Gdf5, PthrP/Pthlh, Col9a2, and Col10a1 from the Ensembl genome browser. Labelled probes were generated for these genes and in situ hybridisations were performed on wild type zebrafish larvae. In addition, we generated transgenic reporter lines by modification of bacterial artificial chromosomes (BACs) containing full length promoters for col2a1 and col10a1. RESULTS: For the first time, we show the spatiotemporal expression pattern of Mcf2l. Furthermore, we show that all six putative OA genes are dynamically expressed during zebrafish larval development, and that all are expressed in the developing skeletal system. Furthermore, we demonstrate that the transgenic reporters we have generated for col2a1 and col10a1 can be used to visualise chondrocyte hypertrophy in vivo. CONCLUSION: In this study we describe the expression pattern of six OA susceptibility genes in zebrafish larvae and the generation of two new transgenic lines marking chondrocytes at different stages of maturation. Moreover, the tools used demonstrate the utility of the zebrafish model for functional studies on genes identified as playing a role in OA.


Assuntos
Modelos Animais de Doenças , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Predisposição Genética para Doença/genética , Osteoartrite/genética , Osteoartrite/fisiopatologia , Peixe-Zebra/genética , Peixe-Zebra/fisiologia , Animais , Animais Geneticamente Modificados , Condrócitos/patologia , Cromossomos Artificiais Bacterianos/genética , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Colágeno Tipo II/fisiologia , Colágeno Tipo IX/genética , Colágeno Tipo IX/metabolismo , Colágeno Tipo IX/fisiologia , Colágeno Tipo X/genética , Colágeno Tipo X/metabolismo , Colágeno Tipo X/fisiologia , Fator 5 de Diferenciação de Crescimento/genética , Fator 5 de Diferenciação de Crescimento/fisiologia , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/fisiologia , Hipertrofia/genética , Proteína Relacionada ao Hormônio Paratireóideo/genética , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/fisiologia
2.
J Evol Biol ; 25(3): 522-31, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22239486

RESUMO

Body size and morphology are key fitness-determining traits that can vary genotypically. They are likely to be important in social insect queens, which mate in swarms and found colonies independently, but genetic influences on queen morphology have been little investigated. Here, we show that the body size and morphology of queens are influenced by their genotype in the leaf-cutting ant Acromyrmex echinatior, a species in which certain lineages (patrilines) bias their development towards reproductive queens rather than sterile workers. We found no relationship between the queen-worker skew of patrilines and the size or morphology of queens, but there was a significant relationship with fluctuating asymmetry, which was greater in more queen-biased patrilines. Our results suggest that queen-biased patrilines do not incur a fitness cost in terms of body size, but may face more subtle costs in developmental stability. Such costs may constrain the evolution of royal cheating in social insects.


Assuntos
Formigas/genética , Formigas/fisiologia , Evolução Biológica , Tamanho Corporal/fisiologia , Aptidão Genética/fisiologia , Hierarquia Social , Análise de Variância , Animais , Pesos e Medidas Corporais , Feminino , Aptidão Genética/genética , Genótipo , Repetições de Microssatélites/genética , Panamá , Reação em Cadeia da Polimerase , Análise de Componente Principal , Estatísticas não Paramétricas , Asas de Animais/anatomia & histologia
3.
Phys Rev Lett ; 102(1): 011801, 2009 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-19257180

RESUMO

Using 2.45x10;{7} psi(2S) decays collected with the CLEO-c detector at the Cornell Electron Storage Ring we present the most precise measurements of magnetic dipole transitions in the charmonium system. We measure B(psi(2S)-->gammaeta_{c})=(4.32+/-0.16+/-0.60)x10;{-3}, B(J/psi-->gammaeta_{c})/B(psi(2S)-->gammaeta_{c})=4.59+/-0.23+/-0.64, and B(J/psi-->gammaeta_{c})=(1.98+/-0.09+/-0.30)%. We observe a distortion in the eta_{c} line shape due to the photon-energy dependence of the magnetic dipole transition rate. We find that measurements of the eta_{c} mass are sensitive to the line shape, suggesting an explanation for the discrepancy between measurements of the eta_{c} mass in radiative transitions and other production mechanisms.

4.
Phys Rev Lett ; 102(6): 061801, 2009 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-19257578

RESUMO

Using psi(2S)-->pi;{+}pi;{-}J/psi, J/psi-->gammaeta;{'} events acquired with the CLEO-c detector at the CESR e;{+}e;{-} collider, we make the first observations of the decays eta;{'}-->pi;{+}pi;{-}pi;{0} and eta;{'}-->pi;{+}pi;{-}e;{+}e;{-}, measuring absolute branching fractions (37_{-9};{+11}+/-4)x10;{-4} and (25_{-9};{+12}+/-5)x10;{-4}, respectively. For eta;{'}-->pi;{+}pi;{-}pi;{0}, this result probes the mechanism of isospin violation and the roles of pi;{0}/eta/eta;{'}-mixing and final state rescattering in strong decays. We also set upper limits on branching fractions for eta;{'} decays to pi;{+}pi;{-}micro;{+}micro;{-}, 2(pi;{+}pi;{-}), pi;{+}pi;{-}2pi;{0}, 2(pi;{+}pi;{-})pi;{0}, 3(pi;{+}pi;{-}), and invisible final states.

5.
Phys Rev Lett ; 102(8): 081801, 2009 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-19257732

RESUMO

Using a 281 pb-1 data sample collected at the psi(3770) resonance with the CLEO-c detector at the Cornell Electron Storage Ring, we report the first observation of D+ --> etae + nue. We also set upper limits for D+ --> eta'e + nue and D + --> varphie + nue that are about 2 orders of magnitude more restrictive than those obtained by previous experiments.

6.
Phys Rev Lett ; 101(15): 151801, 2008 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-18999588

RESUMO

Using a total of 2.74 x 10(7) decays of the psi(2S) collected with the CLEO-c detector, we present a study of chi(cJ)-->gammaV, where V=rho(0), omega, phi. The transitions chi(c1)-->gammarho(0 and chi(c1)-->gammaomega are observed with B(chi(c1)-->gammarho(0))=(2.43+/-0.19+/-0.22) x 10(-4) and B(chi(c1)-->gammaomega)=(8.3+/-1.5+/-1.2) x 10(-5). In the chi(c1)-->gammarho(0) transition, the final state meson is dominantly longitudinally polarized. Upper limits on the branching fractions of other chi(cJ) states to light vector mesons are presented.

7.
Phys Rev Lett ; 100(22): 221801, 2008 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-18643413

RESUMO

We exploit the quantum coherence between pair-produced D0 and D[over]0 in psi(3770) decays to study charm mixing, which is characterized by the parameters x and y, and to make a first determination of the relative strong phase delta between D0-->K+pi- and D[over]0-->K+pi-. Using 281 pb(-1) of e+e- collision data collected with the CLEO-c detector at Ecm=3.77 GeV, as well as branching fraction input and time-integrated measurements of RM identical with (x2 + y2)/2 and RWS identical with Gamma(D0-->K+pi-)/Gamma(D[over]0-->K+pi-) from other experiments, we find cosdelta=1.03(-0.17)(+0.31)+/-0.06, where the uncertainties are statistical and systematic, respectively. By further including other mixing parameter measurements, we obtain an alternate measurement of cosdelta=1.10+/-0.35+/-0.07, as well as x sindelta=(4.4(-1.8)(+2.7)+/-2.9)x10(-3) and delta=(22(-12-11)(+11+9)) degrees .

8.
Phys Rev Lett ; 100(16): 161804, 2008 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-18518186

RESUMO

The branching fractions of D(s)(+/-) meson decays serve to normalize many measurements of processes involving charm quarks. Using 298 pb(-1) of e(+)e(-) collisions recorded at a center of mass energy of 4.17 GeV, we determine absolute branching fractions for eight D(s)(+/-) decays with a double tag technique. In particular we determine the branching fraction B(D(s)(+)-->K(-)K(+}pi(+))=(5.50+/-0.23+/-0.16)%, where the uncertainties are statistical and systematic, respectively. We also provide partial branching fractions for kinematic subsets of the K(-)K(+)pi(+) decay mode.

9.
Phys Rev Lett ; 100(18): 181802, 2008 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-18518362

RESUMO

Using e+e--->Ds*-Ds+ data collected near the peak Ds production energy, Ecm=4170 MeV, with the CLEO-c detector, we present the first observation of the decay Ds+-->pn. We measure a branching fraction B(Ds+-->pn)=(1.30+/-0.36(-0.16)+0.12)x10(-3). This is the first observation of a charmed meson decaying into a baryon-antibaryon final state.

10.
Phys Rev Lett ; 99(4): 041802, 2007 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-17678351

RESUMO

We study semileptonic B decay to the exclusive charmless states pi, rho/omega, eta, and eta;{'} using the 16 fb(-1) CLEO Upsilon(4S) data sample. We find B(B0-->pi-l+nu)=(1.37+/-0.15stat+/-0.11sys)x10(-4) and B(B0-->rho-l+nu)=(2.93+/-0.37stat+/-0.37sys)x10(-4) and find evidence for B+-->eta'l+nu, with B(B+-->eta'l+nu)=(2.66+/-0.80stat+/-0.56sys)x10(-4). From our B-->pilnu rate for q2>16 GeV2 and lattice QCD, we find |Vub|=(3.6+/0.4stat+/0.2syst-0.4thy+0.6)x10(-3) [corrected]

11.
Phys Rev Lett ; 98(9): 092002, 2007 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-17359150

RESUMO

A precision measurement of the D0 meson mass has been made using approximately 281 pb(-1) of e+e- annihilation data taken with the CLEO-c detector at the psi(3770) resonance. The exclusive decay D0-->K_{S}phi has been used to obtain M(D0)=1864.847+/-0.150(stat)+/-0.095(syst) MeV. This corresponds to M(D0D*0)=3871.81+/-0.36 MeV, and leads to a well-constrained determination of the binding energy of the proposed D0D*0 molecule X(3872), as Eb=0.6+/-0.6 MeV.

12.
J Agric Saf Health ; 11(2): 265-72, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15931952

RESUMO

This article examines various environmental alternatives within the context of forest resource-dependent communities of the State of Oaxaca, Mexico. Two main objectives were to describe particular rural development routes among different Mexican communities, and to explain why certain environmental options for rural development are selected over others. While many communities choose either sustainable or illegal logging options in Oaxaca, some may decide against logging of any kind. Four principal forest-based community categories, according to a government forest classification scheme, are discussed in the context of environmental alternatives for this article. Based on this typology, two "integrated forest management" communities in the Sierra Norte of Oaxaca are described and compared. One community's decision not to log within a shared land arrangement has caused significant tensions in the region. Key findings illustrate the extent to which rural communities can make appropriate environmental decisions and examines their effects on environmental and social sustainability. Increased rural involvement in environmental decision-making is called for, since rural residents are those most likely to appreciate nearby natural resources as a source of sustainable livelihoods. It is expected that this research may be applicable to rural areas of other countries.


Assuntos
Conservação dos Recursos Naturais , Agricultura Florestal , Planejamento Social , Saúde Ambiental , Humanos , México , População Rural
13.
Am J Gastroenterol ; 95(7): 1844, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10926005
14.
J Biol Chem ; 275(26): 20012-9, 2000 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-10747936

RESUMO

The crystal structure is reported at 1.8 A resolution of Escherichia coli ornithine transcarbamoylase in complex with the active derivative of phaseolotoxin from Pseudomonas syringae pv. phaseolicola, N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine. Electron density reveals that the complex is not a covalent adduct as previously thought. Kinetic data confirm that N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine exhibits reversible inhibition with a half-life in the order of approximately 22 h and a dissociation constant of K(D) = 1.6 x 10(-12) m at 37 degrees C and pH 8.0. Observed hydrogen bonding about the chiral tetrahedral phosphorus of the inhibitor is consistent only with the presence of the R enantiomer. A strong interaction is also observed between Arg(57) Nepsilon and the P-N-S bridging nitrogen indicating that imino tautomers of N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine are present in the bound state. An imino tautomer of N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine is structurally analogous to the proposed reaction transition state. Hence, we propose that N(delta)-(N'-sulfodiaminophosphinyl)-l-ornithine, with its three unique N-P bonds, represents a true transition state analogue for ornithine transcarbamoylases, consistent with the tight binding kinetics observed.


Assuntos
Ornitina Carbamoiltransferase/metabolismo , Ornitina/análogos & derivados , Sítios de Ligação , Catálise , Cristalografia por Raios X , Elétrons , Escherichia coli/enzimologia , Cinética , Ligantes , Modelos Moleculares , Dados de Sequência Molecular , Nitrogênio/metabolismo , Ornitina/química , Ornitina/farmacologia , Ornitina Carbamoiltransferase/antagonistas & inibidores , Ornitina Carbamoiltransferase/química , Conformação Proteica , Fatores de Tempo
16.
Hum Exp Toxicol ; 18(3): 162-7, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10215106

RESUMO

Blooms of cyanobacteria or blue-green algae are known to have caused poisoning in fish, waterfowl, animals and man. One of the toxins responsible for this is the hepatotoxin microcystin-LR which has been found to occur in blooms present intermittently in sources used for domestic water supplies. Three sets of experiments were undertaken to investigate the acute toxicity of microcystin-LR in mice and rats by the oral and intraperitoneal routes, the potential for effects on foetal development in the mouse, and the effects of repeated oral dosing over 13 weeks in the mouse. The results of this work were as follows: (1) Microcystin-LR is 30-100 times less toxic via oral ingestion than via intraperitoneal injection; (2) Microcystin-LR is not a selective developmental toxicant in the mouse. There was a No Observed Adverse Effect Level (NOAEL) of 600 microg kg(-1) bodyweight per day given on days 6-15 of pregnancy for any form of developmental toxicity; (3) There was a clear NOAEL for tissue damage in the liver of 40 microg kg(-1) bodyweight per day of microcystin-LR. Using this data, a value of 1 microg l(-1) microcystin-LR would be an appropriate guideline value for drinking water.


Assuntos
Toxinas Bacterianas/toxicidade , Peptídeos Cíclicos/toxicidade , Anormalidades Induzidas por Medicamentos/etiologia , Administração Oral , Animais , Toxinas Bacterianas/química , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Feminino , Injeções Intraperitoneais , Dose Letal Mediana , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Toxinas Marinhas , Camundongos , Microcistinas , Nível de Efeito Adverso não Observado , Osteogênese/efeitos dos fármacos , Peptídeos Cíclicos/química , Gravidez , Ratos , Testes de Toxicidade
17.
Hum Exp Toxicol ; 18(3): 168-73, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10215107

RESUMO

Blooms of cyanobacteria are known to have caused poisoning in fish, waterfowl, animals and man. One of the low molecular weight toxins responsible for this is the neurotoxin anatoxin-a which has been detected in reservoirs used for domestic water supplies. While the acute behaviour of this alkaloid is clear, there is uncertainty regarding the effects on man of ingestion of anatoxin-a at low levels over longer periods. In order to assess this risk, a series of in vitro and in vivo experiments were undertaken to investigate the pharmacology, subacute toxicity, and the teratogenicity of anatoxin-a in the mouse. The results of this work were as follows: (1) Pharmacological screening studies confirmed that anatoxin-a is a potent nicotinic agonist which can produce neuromuscular blockade and death by respiratory arrest. Recovery from a single sub-lethal dose is rapid and complete; (2) Repeated sub-lethal oral administration over 28 days in the mouse did not produce any reliable evidence of treatment-related toxicity; (3) From a preliminary screening study anatoxin-a does not appear to be a developmental toxicant in the mouse. These results indicate that a guideline value for anatoxin-a in drinking water of 1 microg l(-1) would provide an adequate margin of safety.


Assuntos
Toxinas Bacterianas/toxicidade , Toxinas Marinhas/toxicidade , Anormalidades Induzidas por Medicamentos/etiologia , Animais , Toxinas Bacterianas/química , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Sistema Nervoso Central/efeitos dos fármacos , Galinhas , Toxinas de Cianobactérias , Avaliação Pré-Clínica de Medicamentos , Feminino , Cobaias , Íleo/efeitos dos fármacos , Técnicas In Vitro , Masculino , Toxinas Marinhas/química , Camundongos , Microcistinas , Contração Muscular/efeitos dos fármacos , Músculos do Pescoço/efeitos dos fármacos , Músculos do Pescoço/fisiologia , Nicotina/farmacologia , Nível de Efeito Adverso não Observado , Nervo Frênico/efeitos dos fármacos , Gravidez , Desempenho Psicomotor/efeitos dos fármacos , Desempenho Psicomotor/fisiologia , Ratos , Testes de Toxicidade , Tropanos
18.
JAMA ; 276(5): 375-81, 1996 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-8683815

RESUMO

OBJECTIVE: To characterize incidence of illnesses and injuries from 1979 to 1993 in former naval aviator prisoners of war (POWs) from the Vietnam War and a comparison group of naval aviators from the same war. DESIGN: Cohort analytic study. SETTING: A US Navy primary care clinic. PARTICIPANTS: Volunteer sample consisting of 70 former naval aviator POWs (white men, aged 47 to 69 years in 1993) and a comparison group of 55 naval aviators who served in Vietnam but were not POWs, matched on race, age, marital status, education, rank, year of entry into the navy, and pilot status. Subjects participated in an annual health screening program. This study reports data sampled on a biennial basis from subjects screening both in 1979 and 1993. MAIN OUTCOME MEASURE: Medically diagnosed incidence of illness and injury based on a standard protocol. RESULTS: POWs had higher incidence rates than the comparison group did of disorders of the peripheral nervous system (relative risk [RR], 8.4; 95% confidence interval [CI], 2.7-25.9; P<.001), joints (RR, 1.5; 95% CI, 1.2-2.0; P<.006), and back RR, 1.8; 5% CI, 1.0-3.0; P<.037). These findings also were statistically significant according to Kaplan-Meier survival analyses that included 131 (95%) of 138 POWs and 115 (83%) of the 138 members of the comparison group. Survival analyses revealed that, in addition to these disorders, POWs had higher hazard rates of peptic ulcer (P<.01). CONCLUSIONS: During captivity, ropes, ratchet handcuffs, leg irons, or stocks were used to put tightly constrictive pressure around the extremities of POWs as a means of torture, resulting in painful ischemia and subsequent neuropathies. Being a former POW was associated with increased cumulative incidence rates of chronic disorders of the peripheral nervous system, joints, and back and an increased hazard rate of peptic ulcer.


Assuntos
Nível de Saúde , Militares , Prisioneiros , Tortura , Guerra , Idoso , Humanos , Estudos Longitudinais , Masculino , Transtornos Mentais/epidemiologia , Transtornos Mentais/etiologia , Saúde Mental , Pessoa de Meia-Idade , Doenças Musculoesqueléticas/epidemiologia , Doenças Musculoesqueléticas/etiologia , Úlcera Péptica/epidemiologia , Úlcera Péptica/etiologia , Doenças do Sistema Nervoso Periférico/epidemiologia , Doenças do Sistema Nervoso Periférico/etiologia , Estatística como Assunto , Tortura/psicologia , Estados Unidos , Vietnã
20.
J Prim Prev ; 16(4): 413-36, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24254855

RESUMO

Use of community coalitions as a strategy for the primary prevention of tobacco, alcohol, and other drug abuse is justified in part on the prospect that these coalitions will mount comprehensive, multi-level, multi-target intervention packages. To judge the success of such coalitions, reliable and valid means for assessing the content and pattern of their overall prevention efforts are required. This article proposes a typology of prevention activities, discusses the logic on which it is based, and provides examples of useful applications in examining community coalition prevention plans. Evidence for reliability and validity is provided through assessments of inter-rater agreement, and the relation of measures of "scope of prevention activities" to independent ratings of comprehensiveness. The typology can be used in research validating the logic model on which prevention coalitions are based, and it is also demonstrably useful for improving the local planning process.

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