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1.
Appl Environ Microbiol ; 75(2): 547-50, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19028913

RESUMO

At least two types of Wolbachia bacteria were detected in wild and insectarium-raised Rhodnius pallescens, a natural vector of Trypanosoma cruzi and Trypanosoma rangeli. Wolbachia was detected in all the organs and tissues studied and in the feces, and this provided a methodological advantage for determining the presence of this endosymbiont in this host, obviating the need to kill the specimens. The occurrence of trypanosomatids in wild individuals was also studied.


Assuntos
Estruturas Animais/microbiologia , Fezes/microbiologia , Rhodnius/microbiologia , Wolbachia/isolamento & purificação , Animais , Trypanosomatina/isolamento & purificação
2.
Science ; 209(4456): 617-9, 1980 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17756845

RESUMO

Experimental obliteration of high-contrast wing stripes of the neotropical butterfly Anartia fatima affected neither survival nor wing damage in a natural population over a 5-month period. There is no direct evidence supporting the hypothesis that so-called disruptive wing patterns function as protective coloration in butterflies.

3.
Science ; 289(5477): 291-4, 2000 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-10894775

RESUMO

Stereotyped feeding damage attributable solely to rolled-leaf hispine beetles is documented on latest Cretaceous and early Eocene ginger leaves from North Dakota and Wyoming. Hispine beetles (6000 extant species) therefore evolved at least 20 million years earlier than suggested by insect body fossils, and their specialized associations with gingers and ginger relatives are ancient and phylogenetically conservative. The latest Cretaceous presence of these relatively derived members of the hyperdiverse leaf-beetle clade (Chrysomelidae, more than 38,000 species) implies that many of the adaptive radiations that account for the present diversity of leaf beetles occurred during the Late Cretaceous, contemporaneously with the ongoing rapid evolution of their angiosperm hosts.


Assuntos
Evolução Biológica , Besouros , Fósseis , Plantas Medicinais , Zingiber officinale , Animais , Besouros/classificação , Besouros/fisiologia , Comportamento Alimentar , Zingiber officinale/classificação , Zingiber officinale/parasitologia , Filogenia , Folhas de Planta
4.
Heredity (Edinb) ; 101(5): 420-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18648384

RESUMO

Wolbachia are maternally inherited intracellular bacteria known to manipulate the reproduction of their arthropod hosts. Wolbachia commonly affect the sperm of infected arthropods. Wolbachia-modified sperm cannot successfully fertilize unless the female is infected with the same Wolbachia type. A study of spermatogenesis in the parasitic wasp Nasonia vitripennis reveals that Wolbachia are not required in individual spermatocytes or spermatids to modify sperm. In N. vitripennis, Wolbachia modify nearly all sperm, but are found only in approximately 28% of developing sperm, and are also found in surrounding cyst and sheath cells. In the beetle Chelymorpha alternans, Wolbachia can modify up to 90% of sperm, but were never observed within the developing sperm or within the surrounding cyst cells; they were abundant within the outer testis sheath. We conclude that the residence within a developing sperm is not a prerequisite for Wolbachia-induced sperm modification, suggesting that Wolbachia modification of sperm may occur across multiple tissue membranes or act upstream of spermiogenesis.


Assuntos
Espermatogênese , Espermatozoides/crescimento & desenvolvimento , Espermatozoides/microbiologia , Vespas/crescimento & desenvolvimento , Vespas/microbiologia , Wolbachia/fisiologia , Animais , Besouros/crescimento & desenvolvimento , Besouros/microbiologia , Feminino , Masculino , Especificidade da Espécie
5.
Environ Entomol ; 37(1): 224-9, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18348814

RESUMO

Accurate descriptions of feeding habits are essential to understanding the evolution of dietary preferences and the high levels of diversification within the Chrysomelidae. Both primary observations and summaries suggest that the cassidine beetle tribe, Cephaloleiini, is a species-rich group of feeding specialists on monocot hosts. However, accurate host ranges are poorly defined for most hispine beetle species. To better document occurrence and feeding, we censused the Cephaloleiini associated with rolled leaves of five species of Marantaceae and six species of Heliconiaceae (Zingiberales) in lowland Central Panama. Additionally, we conducted choice and no-choice feeding tests on a subset of both the plants and beetles encountered in the censuses. Both types of data suggest that most species of Cephaloleiini feed on a greater variety of related plant species than has previously been reported.


Assuntos
Besouros/fisiologia , Zingiberales/metabolismo , Animais , Ecossistema , Comportamento Alimentar/fisiologia , Preferências Alimentares/fisiologia , Panamá , Clima Tropical
6.
Child Care Health Dev ; 34(1): 71-6, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18171447

RESUMO

BACKGROUND: The long-term consequences of intrauterine exposure to Class A drugs are still relatively undocumented, and much of the literature relates to the North American experience, where cocaine use predominates. In Britain, heroin and amphetamine use is more common and, within Britain, patterns of drug use vary. Clearly the long-term educational and welfare needs of these children will be enhanced if the behavioural, developmental and child-care outcomes are known. This study attempts to explore some of these issues. METHODS: The developmental, behavioural and child protection outcomes in a group of 62 children exposed to Class A drugs in utero were investigated when the children were in full-time schooling. RESULTS: Seventy-four per cent (46/62) of the children at the time of the study had no educational or behavioural problems, and 11 (17.7%) were receiving extra support in school. No child had a statement of special educational need. Twelve (19.3%) were reported to have behaviour and concentration problems, and in four cases, this was attributed to poor-quality parenting at the time of the study. Three of the 12 children had fetal alcohol syndrome. Twenty-six (42%) children were placed on the Child Protection Register, and care orders or residence orders were granted for 22 (35.5%) of those who were placed on the register. All of the 22 children went into substitute care at some stage. Of these children, nine were adopted and 10 were placed permanently with other family members. Ten of the 62 (16.1%) children at the time of the study were of concern to professionals for child protection reasons, and four of them were on the Child Protection Register. CONCLUSIONS: This study suggests we can be reasonably optimistic about the developmental and behavioural outcomes for children exposed to Class A drugs in utero. Over 50% required an intervention by social services, and 31% were in substitute care at the time of the study. There were continuing child protection concerns in 16% at school entry.


Assuntos
Desenvolvimento Infantil , Proteção da Criança , Deficiências do Desenvolvimento/epidemiologia , Efeitos Tardios da Exposição Pré-Natal , Transtornos Relacionados ao Uso de Substâncias/complicações , Criança , Pré-Escolar , Educação Inclusiva , Feminino , Transtornos do Espectro Alcoólico Fetal/epidemiologia , Cuidados no Lar de Adoção , Humanos , Masculino , Gravidez
8.
Proc Biol Sci ; 267(1450): 1277-85, 2000 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-10972121

RESUMO

Wolbachia are a group of cytoplasmically inherited bacteria that cause reproduction alterations in arthropods, including parthenogenesis, reproductive incompatibility, feminization of genetic males and male killing. Previous general surveys of insects in Panama and Britain found Wolbachia to be common, occurring in 16-22% of species. Here, using similar polymerase chain reaction methods, we report that 19.3% of a sample of temperate North American insects are infected with Wolbachia, a frequency strikingly similar to frequencies found in two other studies in widely separated locales. The results may indicate a widespread equilibrium of Wolbachia infection frequencies in insects whose maintenance remains to be explained. Alternatively, Wolbachia may be increasing in global insect communities. Within each of the three geographic regions surveyed, Hymenoptera are more frequently infected with A group Wolbachia and Lepidoptera more frequently infected with B group Wolbachia.


Assuntos
Insetos/microbiologia , Wolbachia , Animais , DNA Bacteriano/genética , América do Norte , Reação em Cadeia da Polimerase , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Wolbachia/genética , Wolbachia/isolamento & purificação
9.
Biochem Pharmacol ; 42(7): 1493-5, 1991 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-1930274

RESUMO

The results of the present study strongly suggest that the hypertriglyceridaemia in chicks treated with Aroclor 1254 is a result of reduction in VLDL clearance rather than an increase in rate of VLDL secretion. The decrease in post-heparin LPL activity responsible for reduced VLDL clearance may be mediated by cytokines produced by chronic activation of the immune system.


Assuntos
Lipoproteínas/metabolismo , Bifenilos Policlorados/toxicidade , Ácido 3-Hidroxibutírico , Animais , Arocloros/toxicidade , Galinhas , Meia-Vida , Hidroxibutiratos/sangue , Hipertrigliceridemia/induzido quimicamente , Lipase Lipoproteica/sangue , Lipoproteínas/sangue , Lipoproteínas VLDL/sangue , Triglicerídeos/sangue
10.
Science ; 193(4250): 274, 1976 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-17745706
11.
Science ; 194(4272): 1377, 1976 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-17819261
12.
Science ; 287(5458): 1592-3, 2000 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-10733425
13.
Science ; 152(3722): 591, 1966 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-17779486
14.
J Androl ; 20(2): 280-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10232663

RESUMO

The fertility of ewes after artificial insemination and the relationship between fertility and motility characteristics assessed by a computerized motility analysis system were examined with ram semen frozen in diluents reported to improve postthaw motility. The percentages of motile and progressive spermatozoa were better when frozen in proline- or glycine betaine-containing or HEPES-based, rather than Tris-based, diluents (P < 0.01). The fertility of spermatozoa frozen in diluents containing proline or glycine betaine was slightly reduced, whereas when both compatible solutes were present, the reduction was more pronounced, in comparison with semen frozen in Tris- or HEPES-based diluents (9.5 versus 71.1 and 66.6%; P < 0.01). Fertility of frozen-thawed spermatozoa was higher after laparoscopic insemination than after cervical or transcervical insemination (P < 0.01). Similarly, higher fertility was obtained after cervical insemination with fresh than with frozen-thawed semen (32.4 versus 11.3%; P < 0.01). Furthermore, loss of embryos was lower after laparoscopic insemination of ewes with semen frozen in a Tris diluent than with semen frozen in proline diluents, in glycine betaine diluents, or in proline-plus-glycine betaine diluents (0.0 versus 26.0, 38.5, and 60.0%; P < 0.001). A wide variation in the postthaw percentage of motile (31.6-59.7%) and progressive (22.6-43.1%) spermatozoa and in the fertility of spermatozoa from individual rams was also observed after laparoscopic (29.2-59.7%) or cervical insemination (8.7-30.5%). Postthaw motility results from immediately after thawing and fertility results from experiments where intrauterine insemination was performed with semen frozen in proline- or glycine betaine-containing or HEPES- or Tris-based diluents were pooled and subjected to a pairwise correlation procedure. The correlation analysis showed relationships between some of the motility characteristics (P < 0.01), but there were no relationships between the motility characteristics and fertility.


Assuntos
Fertilidade , Inseminação Artificial , Motilidade dos Espermatozoides , Animais , Colo do Útero , Criopreservação , Feminino , Morte Fetal/veterinária , Masculino , Taxa de Gravidez , Ovinos , Útero
15.
J Infect ; 43(4): 234-8, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11869060

RESUMO

Patients with primary antibody deficiency (PAD) are prone to mycoplasma infection with unusual strains which may be resistant to conventional antibiotics. Mycoplasmas were isolated from the joint fluid (Ureaplasma urealyticum) of two PAD patients with arthritis and from the cerebral spinal fluid (Mycoplasma maculosum) in one with meningitis, the latter probably originating from the patient's dog. Combinations of doxycycline and quinolones or macrolides failed to clear the infections, but after demonstrating in-vitro sensitivity to the pleuromutilin, Econor, for two of the isolates, all three patients responded to oral treatment with Econor. The infection was completely eradicated in two patients, with the emergence of a resistant strain in the third. Mycoplasma infection should be considered in PAD patients with unexplained sepsis. Pleuromutilins such as Econor are powerful new anti-mycoplasmal agents which provide an additional therapeutic option when patients fail to respond to conventional antibiotics.


Assuntos
Antibacterianos/uso terapêutico , Imunodeficiência de Variável Comum/complicações , Diterpenos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Hospedeiro Imunocomprometido , Infecções por Mycoplasma/tratamento farmacológico , Infecções por Ureaplasma/tratamento farmacológico , Adolescente , Adulto , Feminino , Humanos , Masculino , Mycoplasma/efeitos dos fármacos , Mycoplasma/isolamento & purificação , Infecções por Mycoplasma/imunologia , Compostos Policíclicos , Resultado do Tratamento , Infecções por Ureaplasma/imunologia , Ureaplasma urealyticum/efeitos dos fármacos , Ureaplasma urealyticum/isolamento & purificação , Pleuromutilinas
16.
Reprod Fertil Dev ; 9(3): 279-84, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9261876

RESUMO

These experiments investigated the effect of freezing on mitochondrial function in ram sperm, the effectiveness of current freezing procedures in protecting mitochondria, and the role of mitochondrial respiration in cervical penetration and transit by ram sperm. Only sperm with functioning mitochondria (assessed by rhodamine 123 staining) after freezing and thawing were motile in a viscous medium (P < 0.05). A simplified rhodamine 123 uptake assay was developed to monitor sperm mitochondrial function. The results of this procedure were highly correlated (r2 = 0.98) with the proportion of damaged sperm in the semen sample. A semen freezing procedure commonly used by industry was compared with newer methods, and with freezing without cryoprotectants. None of the freezing protocols produced sperm with higher post-thaw levels of mitochondrial integrity than unprotected sperm. Merino ewes were inseminated with semen treated with metabolic inhibitors. Glycolytic inhibition did not affect fertility. Mitochondrial inhibition reduced fertility in cervically (P < 0.05), but not laparoscopically inseminated ewes. It is concluded that mitochondrial respiration plays an important part in penetration of the cervix by ram sperm. Mitochondrial injury during freezing is likely to be implicated in the poor fertility of frozen ram semen used for cervical insemination.


Assuntos
Fertilidade/fisiologia , Mitocôndrias/metabolismo , Ovinos/fisiologia , Espermatozoides/metabolismo , Animais , Antimetabólitos/farmacologia , Respiração Celular/efeitos dos fármacos , Criopreservação/métodos , Criopreservação/veterinária , Desoxiglucose/farmacologia , Feminino , Fertilidade/efeitos dos fármacos , Corantes Fluorescentes , Técnicas In Vitro , Inseminação Artificial/veterinária , Masculino , Microscopia de Fluorescência , Mitocôndrias/efeitos dos fármacos , Rodamina 123 , Rodaminas , Rotenona/farmacologia , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides/efeitos dos fármacos , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/efeitos dos fármacos
17.
Reprod Fertil Dev ; 7(1): 129-34, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7569051

RESUMO

Post-thaw characteristics of ram semen frozen as pellets were assessed using biochemically (amidase activity) or motility-based (Hamilton Thorn Motility Analyzer) techniques. The total variation associated with each semen characteristic measured was partitioned between rams (5), ejaculates within rams (5), pellets within ejaculates (5) and within pellets (2). A variety of variance distributions were observed for the characteristics measured. Of the 18 post-thaw characteristics examined, 10 had > 50% of variance distributed between within-ejaculate components. This has important implications for the way in which such measurements may be used in post-thaw semen analysis.


Assuntos
Criopreservação , Motilidade dos Espermatozoides , Espermatozoides , Análise de Variância , Animais , Masculino , Ovinos
19.
Anim Reprod Sci ; 47(1-2): 21-9, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9233503

RESUMO

Two field experiments were conducted to investigate the amount of variation between rams, and between ejaculates within rams, in the fertility of frozen-thawed semen used for cervical insemination. Individual ejaculates from seven Merino rams were frozen and used to cervically inseminate Merino ewes at a synchronized oestrus at two sites. In Experiment 1 (N = 491), pregnancy rates (determined 70-80 days after insemination) for individual rams ranged from 1.8 to 11.9%. Individual ejaculates produced pregnancy rates between 0 and 21.4%. Overall conception rate was 6.5%. No significant differences were detected. Pregnancy rates for the same rams in Experiment 2 (N = 449) varied from 10.3 to 32.6% (P < 0.05). Ejaculate pregnancy rates ranged between 0 and 60% (P < 0.01). Fertility of individual ejaculates within rams differed for three of the seven rams used (P < 0.01). It is concluded that considerable variation in fertility of frozen ram semen exists between ejaculates within rams as well as between rams. Possible sources (biological and arising from freezing artefacts) of such variation and their practical implications are discussed.


Assuntos
Criopreservação/veterinária , Fertilidade/fisiologia , Inseminação Artificial/veterinária , Preservação do Sêmen/veterinária , Sêmen/fisiologia , Ovinos/fisiologia , Animais , Criopreservação/métodos , Sincronização do Estro , Feminino , Inseminação Artificial/métodos , Masculino , Gravidez , Taxa de Gravidez , Preservação do Sêmen/métodos
20.
Theriogenology ; 43(6): 1009-18, 1995 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-16727688

RESUMO

The experiments described examined the effects of a number of factors on the level of uterine insemination achieved in Merino ewes by a transcervical insemination technique (Guelph system for transcervical artificial insemination; GST-AI). Cervical penetration rate is an important limitation to the use of such methods in Merinos. Simulated insemination was performed to estimate the proportion of ewes in which a pipette could be passed through the cervix to the uterus. In Experiment 1, cervical penetration rate (n = 14 to 30) was unaffected by an increase in postpartum interval at AI from 12 to 26 wk. The results of cervical penetration for individual ewes were found to be repeatable (P < 0.05). Experiment 2 (197 ewes) revealed a clear effect of ewe parity on penetration rates in hormonally synchronized ewes during the nonbreeding season (P < 0.05). In Experiment 3, estrus synchronization using progestagen (n = 51) or prostaglandin (n = 50) did not affect penetration rate. The penetration rate was slightly higher in the naturally cycling ewes, but the difference was not significant. Comparison of ewes from Experiments 2 and 3 suggests the possibility of a major effect of stage of the breeding season on the penetration rate (P < 0.05). It is concluded that ewe selection and management techniques may be used to increase the proportion of transcervical insemination attempts resulting in uterine insemination. However, fertility testing will be required to determine whether such improvements translate into correspondingly increased pregnancy rates.

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