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1.
Integr Org Biol ; 1(1): obz024, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-33791538

RESUMO

Microclimatic variation has emerged as an important driver of many ecological and evolutionary processes. Nonetheless, fine-scale temperature data are still rare in most habitats, limiting our ability to understand the consequences of microclimatic variation under current and future conditions. We measured fine-scale thermal variation in a common, species-rich, but rarely studied habitat with respect to temperature: the airspaces under rocks on intertidal zone boulder shores. The effects of thermal variation were investigated using physiological, behavioral, and demographic responses of the porcelain crab Petrolisthes cinctipes. Habitat temperatures were measured at fine spatial and temporal resolution over 18 months, producing 424,426 temperature records. Microclimatic variation increased with increasing intertidal elevation, particularly with respect to heat extremes. However, mean temperatures were similar across the entire intertidal zone. Overheating risk for P. cinctipes increases with intertidal elevation but is size dependent, as large animals are more heat sensitive than small animals. Still, microclimatic variation high in the intertidal zone provided thermal refugia even under the warmest conditions. Size-dependent thermal responses predicted that large crabs should be rare high in the intertidal zone, which was supported by demographic data. Furthermore, simulations parameterized by our microclimate and organismal data recapitulated demographic patterns. Therefore, interactions between microclimatic variation and size-dependent thermal responses may have significant ecological repercussions that warrant greater attention.


Rocas calientes y rocas no tan calientes en la orilla del mar: patrones y consecuencias dependientes del tamaño del cuerpo de la variación microclimática en el hábitat de rocas intermareales (Hot rocks and not-so-hot rocks on the seashore: patterns and body-size dependent consequences of microclimatic variation in intertidal zone boulder habitat) La variación microclimática se ha convertido en un importante impulsor de muchos procesos ecológicos y evolutivos. No obstante, los datos de temperatura a pequeña escala aún son raros en la mayoría de los hábitats, lo que limita nuestra capacidad de comprender las consecuencias de la variación microclimática en las condiciones actuales y futuras. Medimos la variación térmica a pequeña escala en un hábitat común, rico en especies, pero rara vez estudiado con respecto a la temperatura: los espacios aéreos debajo de las rocas en las costas de rocas de zonas intermareales. Los efectos de la variación térmica se investigaron utilizando respuestas fisiológicas, conductuales y demográficas de los cangrejos de porcelana Petrolisthes cinctipes. Las temperaturas del hábitat se midieron con una resolución espacial y temporal fina durante 18 meses, produciendo 424.426 registros de temperatura. La variación microclimática aumentó con el aumento de la elevación intermareal, particularmente con respecto a los extremos de calor. Sin embargo, las temperaturas medias fueron similares en toda la zona intermareal. El riesgo de sobrecalentamiento de P. cinctipes aumenta con la elevación intermareal, pero depende del tamaño, ya que los animales grandes son más sensibles al calor que los animales pequeños. Aún así, la variación microclimática alta en la zona intermareal proporcionó refugios térmicos incluso en las condiciones más cálidas. Las respuestas térmicas dependientes del tamaño predijeron que los cangrejos grandes deberían ser raramente altos en la zona intermareal, lo que fue respaldado por datos demográficos. Además, las simulaciones parametrizadas por nuestros microclimas y datos organismales recapitularon patrones demográficos. Por lo tanto, las interacciones entre la variación microclimática y las respuestas térmicas dependientes del tamaño pueden tener importantes repercusiones ecológicas que justifican una mayor atención. Translated to Spanish by YE Jimenez (yordano_jimenez@brown.edu).


Rochas quentes e rochas não-tão-quentes à beira-mar: padrões e conseqüências dependentes do tamanho coporal para a variação microclimática no habitat de rochas da zona entremarés (Hot rocks and not-so-hot rocks on the seashore: patterns and body-size dependent consequences of microclimatic variation in intertidal zone boulder habitat) A variação microclimática emergiu como um importante causador de muitos processos ecológicos e evolutivos. No entanto, dados de temperatura em escala fina ainda são raros para a maioria dos habitats, limitando nossa capacidade de compreender as conseqüências da variação microclimática sob condições atuais e futuras. Nós medimos a variação térmica numa escala fina em um habitat comum, rico em espécies, mas raramente estudado em relação à temperatura: os espaços aéreos sob as rochas nas margens dos blocos de pedra da zona entremarés. Os efeitos da variação térmica foram investigados usando respostas fisiológicas, comportamentais e demográficas do caranguejo Petrolisthes cinctipes. As temperaturas do habitat foram medidas em resolução espacial e temporal ao longo de 18 meses, produzindo 424.426 registros de temperatura. A variação microclimática aumentou com o aumento da elevação intertidal, particularmente com relação aos extremos de calor. No entanto, as temperaturas médias foram semelhantes em toda a zona entremarés. O risco de superaquecimento de P. cinctipes aumenta com a elevação intertidal, mas é dependente do seu tamanho, já que os animais grandes são mais sensíveis ao calor do que os pequenos. Ainda assim, a variação microclimática alta na zona entremarés forneceu refúgios térmicos mesmo sob as condições mais quentes. Respostas térmicas dependentes do tamanho previam que os grandes caranguejos deveriam ser raros na zona entremarés, o que era apoiado por dados demográficos. Além disso, as simulações parametrizadas pelos nossos dados de microclima e organismal recapitularam padrões demográficos. Portanto, as interações entre a variação microclimática e as respostas térmicas dependentes do tamanho corporal podem ter repercussões ecológicas significativas que merecem maior atenção. Translated to Portuguese by G Sobral (gabisobral@gmail.com).

3.
Brain Cogn ; 44(3): 307-23, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11104528

RESUMO

A pure case of autopsy-confirmed dementia with Lewy bodies (DLB) is described. The patient presented with distinctive verbal fluency deficits in the context of mild language impairment, intact recognition memory, and impaired paragraph recall. Neuroimaging (CT and SPECT) showed progressive medial temporal lobe atrophy. Neuropathology revealed Lewy bodies, degeneration in the substantia nigra, nucleus basalis of Meynert (Nakano & Hirano, 1984), and locus ceruleus, but no pathology characteristic of Alzheimer's disease. It is in this sense that the case is "pure" DLB. Early neuropsychological diagnosis of DLB is essential (Salmon et al., 1996) given the potentially fatal hazard of neuroleptics (McKeith et al., 1992) and the difficulties associated with clinical neurological diagnoses (Litvan et al., 1998).


Assuntos
Encéfalo/diagnóstico por imagem , Demência/diagnóstico , Doença por Corpos de Lewy/diagnóstico , Idoso , Demência/complicações , Evolução Fatal , Humanos , Doença por Corpos de Lewy/complicações , Masculino , Testes Neuropsicológicos , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
4.
J Virol ; 69(11): 7248-56, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7474147

RESUMO

Human T-lymphotropic virus type 1 (HTLV-1) infection has been discovered recently in people of Amerindian descent living in coastal areas of British Columbia, Canada. DNA sequencing combined with phylogenetic analysis and restriction fragment length polymorphism (RFLP) typing of HTLV-1 strains recovered from these British Columbia Indians (BCI) was conducted. Sequence-based phylogenetic trees distributed the BCI isolates among the Japanese subcluster (subcluster B) and the geographically widely distributed subcluster (subcluster A) of the large HTLV-1 cosmopolitan cluster. Long terminal repeat (LTR) RFLP typing revealed three distinct, equally frequent LTR cleavage patterns, two of which were of previously recognized Japanese and widely dispersed cosmopolitan types. A third, new cleavage pattern was detected which may have arisen by recombination between two other HTLV-1 genotypes. Our results suggest multiple origins for HTLV-1 in BCI, which are equally consistent with (i) a cluster of recent sporadic infections, (ii) ancient endemic vertical transmission through Amerindian lineages, or (iii) both.


Assuntos
Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/classificação , Vírus Linfotrópico T Tipo 1 Humano/genética , Filogenia , Polimorfismo de Fragmento de Restrição , Sequência de Bases , Colúmbia Britânica/epidemiologia , Primers do DNA , Demografia , Infecções por HTLV-I/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Humanos , Indígenas Norte-Americanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Sequências Repetitivas de Ácido Nucleico , Especificidade da Espécie
5.
Scand J Immunol ; 40(2): 171-80, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8047838

RESUMO

We have compared the immunoglobulin isotype and IgG subclass and the titre of neutralizing antibody responses to the human T cell lymphotropic virus type I (HTLV-I) between a group of asymptomatic HTLV-I infected individuals and a group with the neurological disease HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP). A western blot titration assay and an envelope peptide ELISA were used to determine the presence and titre of isotype and IgG subclass responses to the gag p19 and p24 proteins and to the envelope protein. Significant increases were observed in the number of individuals seropositive for a particular isotype and IgG subclass in the HAM/TSP group versus the asymptomatic group particularly for IgM and IgE and to a lesser extent, IgA. The predominant IgG subclasses to the HTLV-I p19, p24 and envelope proteins were IgG1 and IgG3. This finding was also observed in the titres of the antibody responses to these HTLV-I proteins. The HAM/TSP group also exhibited significantly higher neutralizing antibody titres than the asymptomatic group. This evidence suggests that some form of chronic immune stimulation might be involved in the immunopathogenesis of HAM/TSP. In addition, by following the Western blot titre to the IgM and IgE isotypes in particular, it may be possible to identify asymptomatic individuals progressing to HAM/TSP.


Assuntos
Produtos do Gene env/imunologia , Produtos do Gene gag/imunologia , Anticorpos Anti-HTLV-I/biossíntese , Infecções por HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Paraparesia Espástica Tropical/imunologia , Ensaio de Imunoadsorção Enzimática , Anticorpos Anti-HTLV-I/classificação , Humanos , Imunoglobulina G/biossíntese , Imunoglobulina G/classificação , Isotipos de Imunoglobulinas/biossíntese , Proteínas Oncogênicas de Retroviridae/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana , Produtos do Gene gag do Vírus da Imunodeficiência Humana
6.
Clin Diagn Virol ; 2(2): 67-78, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15566754

RESUMO

BACKGROUND: Recent epidemiology studies have demonstrated the presence of HTLV-I and its close relative, HTLV-II in several aboriginal populations in North, Central and South America but not in Canadian Indian populations. HTLV-II appears to be more prevalent than HTLV-I in aboriginal populations of the Americas. Recently several clinical cases of HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP) and a case of adult T-cell leukemia (ATL) have been identified in British Columbian Indians. This data suggests that a new endemic area of HTLV-I infection may be present within British Columbian Indian population. However, it has recently been shown that HTLV-II may also be associated with a neurological disease similar to HAM/TSP. OBJECTIVES: The purpose of the work reported here was to demonstrate whether HTLV-I, HTLV-II or both were responsible for the diseases seen in the British Columbian Indians. STUDY DESIGN: In this study serological and gene amplification techniques were used to determine whether HTLV-I or HTLV-II was present in four families and three unrelated individuals all from different bands of aboriginal Native Indians in British Columbia. In each family, one member had an HTLV-associated disease, three cases of HAM/TSP and one case of ATL. Of the three individual aboriginal natives unrelated to the four families, two had HAM/TSP while the third was asymptomatic for HTLV-associated diseases. RESULTS: This study demonstrated the presence of HTLV-I in the aboriginal Indians with disease and in some of their family members. HTLV-II was not detected in any of the British Columbian Indians tested in this study. CONCLUSIONS: These British Columbian Indians represent the first Canadian aboriginal Indians with HTLV-I infection and associated diseases. Furthermore, the British Columbian Indian population may represent a previously unrecognized endemic population of HTLV-I infection.

7.
J Gen Virol ; 74 ( Pt 2): 211-22, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8429302

RESUMO

The entire envelope gene of human T cell leukaemia virus type I (HTLV-I) has been successfully expressed in a baculovirus non-fusion vector system. The HTLV-I envelope protein accumulated within the insect cells as inclusion bodies which allowed efficient recovery of the recombinant protein. In an attempt to study the role of the HTLV-I envelope glycoprotein as an immunogenic target, mice were immunized with the envelope protein inclusion bodies (env-I.B.) in the presence or absence of an adjuvant. Antibodies of broad specificity were produced against the HTLV-I envelope protein in the presence or absence of an adjuvant as detected by Western blotting, radioimmunoprecipitation and peptide ELISA. Neutralizing antibody was detected when env-I.B. immunizations were carried out in the presence of high doses of a new adjuvant composed of a mycobacterial cell wall extract. In a combined immunization regimen, env-I.B. were found to enhance and broaden the antibody response to the HTLV-I envelope glycoprotein, following priming with various recombinant vaccinia virus (RVV) constructs expressing either the entire native HTLV-I envelope (gp46 and gp21) or just the surface envelope protein (gp46). Increased titres of neutralizing antibodies were observed following priming with the RVV expressing gp46 only. Results indicate that immunization regimens that involve priming with RVV expressing HTLV-I envelope followed by boosting with recombinant baculoviral HTLV-I envelope might be useful in eliciting protective immune responses in vivo.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano/imunologia , Corpos de Inclusão Viral/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Antivirais/biossíntese , Baculoviridae , Linhagem Celular , Imunofluorescência , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Humanos , Camundongos , Camundongos Endogâmicos , Proteínas Recombinantes/imunologia , Proteínas do Envelope Viral/isolamento & purificação
8.
Virology ; 191(1): 448-53, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1413516

RESUMO

Recombinant vaccinia viruses (RVV) designated RVV E1, RVV E2, and RVV E3, were constructed to express three different versions of the human T cell leukemia virus type I (HTLV-I) envelope proteins to determine which configuration elicits an optimal antibody response. RVV E1 expressed the native HTLV-I envelope proteins gp46 (surface protein) and gp21 (transmembrane protein), while RVV E2 expressed the envelope precursor with the proteolytic cleavage site deleted. The RVV E3 construct expressed only the external surface glycoprotein, gp46. Radioimmunoprecipitation and FACS analysis confirmed that the appropriate envelope proteins were expressed by RVV E1-, E2-, and E3-infected cells. Immunization studies were carried out using Balb/c, A/J, and C57BL/6 strains of mice. Balb/c mice responded poorly to immunization with all of the three RVV constructs. C57BL/6 mice produced neutralizing antibodies in response to immunization with all three constructs, whereas A/J mice developed neutralizing antibodies only when immunized with the RVV E1s construct. The results indicate that the humoral immune responses depend on the form of HTLV-I envelope proteins expressed by each RVV.


Assuntos
Produtos do Gene env/imunologia , Anticorpos Anti-HTLV-I/imunologia , Proteínas Oncogênicas de Retroviridae/imunologia , Animais , Imunofluorescência , Anticorpos Anti-HTLV-I/biossíntese , Células L , Camundongos , Camundongos Endogâmicos C57BL , Testes de Neutralização , Testes de Precipitina , Ensaio de Radioimunoprecipitação , Proteínas Recombinantes/imunologia , Vaccinia virus/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana
9.
AIDS Res Hum Retroviruses ; 8(7): 1201-7, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1520533

RESUMO

Isolates of HTLV-I have been characterized from a number of different regions of the world; however, there has not been a nucleotide sequence analysis of an HTLV-I isolate from a South American country. Reported here is an individual from Chile identified with the HTLV-I-associated neurological disease HAM/TSP. The sera and the nucleic acid sequence of the HTLV-I present in peripheral blood lymphocytes from this Chilean HAM/TSP patient over a two year period are characterized. During this time, the patient's condition grew progressively worse. While the serological profile of this patient was unremarkable in comparison with other HAM/TSP patients previously described, nucleic acid sequence analysis identified two nucleotide positions which contained nucleotides unique to this Chilean isolate. The nucleotide sequence analysis also indicates that the Chilean HTLV-I isolate is more closely related to Caribbean and Japanese isolates of HTLV-I than to the African and U.S. isolates described so far.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano/genética , Paraparesia Espástica Tropical/microbiologia , Sequência de Bases , Southern Blotting , Linhagem Celular , Chile , DNA Viral , Feminino , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Humanos , Masculino , Dados de Sequência Molecular , Paraparesia Espástica Tropical/sangue , Reação em Cadeia da Polimerase , Homologia de Sequência do Ácido Nucleico , Linfócitos T/microbiologia
11.
Plant Physiol ; 63(2): 260-3, 1979 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16660708

RESUMO

Patterns of accumulation and ontogenetic relationships among proteins of cotton (Gossypium hirsutum L.) seeds were examined between 10 days postanthesis and maturity (56 days). Total and extractable nitrogen contents were determined; alkali- and water-soluble proteins were assayed quantitatively and electrophoretically. Two alkali-soluble proteins present in the electrophoretogram of mature embryos first appeared at 21 days postanthesis; most of the final profile was established by 28 days. Except for minor changes centering around the 7th week of development, the pattern from 28 days to maturity was marked by intensification of bands. The quantity of water-soluble nitrogen increased through the first 21 days of development, then declined until 42 days, when it again began to increase; it reached its highest level at maturity. There was evidence of a high peptide content 7 weeks postanthesis.

12.
Plant Physiol ; 62(4): 531-5, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16660553

RESUMO

Total and free amino acid composition of germinating cotton seeds (Gossypium hirsutum L.) was determined. The germinating seeds were separated into cotyledon and developing axis fractions daily and the composition of each tissue was summed to get the whole seed composition. By separating the developing seeds into these two tissue fractions, and determining total and free amino acids, a balance sheet was developed for each amino acid. This technique allowed changes in distribution with time of each amino acid to be followed in each tissue. Data for total content and amount in protein of each amino acid are presented. Asparagine increased in the whole seed, and most of this increase was found in the free pool of the developing axis. Other amino acids (e.g. arginine, glutamic acid) increased in the free pool but showed an over-all decrease, indicating that they were being metabolized. Amino acid contents of storage and nonstorage protein isolates were determined.

15.
Plant Physiol ; 44(6): 903-6, 1969 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16657143

RESUMO

Protein extracted from boll weevil larvae causes abscission of cotton flower buds and debladed petioles. Abscission of buds is preceded by a rapid and persistent flaring of bracts; cell proliferation is induced in the abscission zone of debladed petioles. A possible mode of transmission of the agent from larva to bud tissue is discussed.

16.
Plant Physiol ; 43(10): 1699-702, 1968 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16656957

RESUMO

Activity of indoleacetic acid oxidase in partially purified extracts from cotton is stimulated by small amounts of malate, succinate, fumarate, and other plant acids. The stimulation is apparently due to inhibition of catalase, which is detectable in certain preparations. The lag phase of indoleacetic acid oxidation by crude preparations is eliminated by steps in processing which conceivably either denatures or dilutes catalase, or concentrates inhibitors to catalase.

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