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1.
Oecologia ; 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36175692

RESUMO

Wind speed can have multifaceted effects on organisms including altering thermoregulation, locomotion, and sensory reception. While forest cover can substantially reduce wind speed at ground level, it is not known if animals living in forests show any behavioural responses to changes in wind speed. Here, we explored how three boreal forest mammals, a predator and two prey, altered their behaviour in response to average daily wind speeds during winter. We collected accelerometer data to determine wind speed effects on activity patterns and kill rates of free-ranging red squirrels (n = 144), snowshoe hares (n = 101), and Canada lynx (n = 27) in Kluane, Yukon from 2015 to 2018. All 3 species responded to increasing wind speeds by changing the time they were active, but effects were strongest in hares, which reduced daily activity by 25%, and lynx, which increased daily activity by 25%. Lynx also increased the number of feeding events by 40% on windy days. These results highlight that wind speed is an important abiotic variable that can affect behaviour, even in forested environments.

2.
Blood Cancer J ; 7(8): e590, 2017 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-28841203

RESUMO

We assessed the ability of a mass spectrometry-based technique, called monoclonal immunoglobulin rapid accurate mass measurement (miRAMM), to extend the analytical range of M-protein detection in serum samples obtained from myeloma patients in stringent complete response (sCR) post-autologous stem cell transplant (ASCT). To aid the M-protein detection post ASCT, the accurate molecular mass of the M-protein light chain at diagnosis was determined in all patients (N=30) and used to positively identify clones in the sCR serum. Day 100 post-ASCT, sCR samples had miRAMM identifiable M-proteins in 81% of patients. Patients who had achieved only a partial remission (PR) pre-ASCT and those with IgG isotypes serum samples had the highest rate of M-protein detection by miRAMM. miRAMM positivity at single time points (day 100, 6 months or 12 months) did not correlate with progression-free survival (PFS). In contrast, sCR patients who did not decrease their miRAMM M-protein intensities in serial measurements had shorter PFS than those whose miRAMM intensities decreased (median 17.9 months vs 51.6 months; P<0.0017). miRAMM M-protein is a more sensitive blood-based test than traditional M-protein tests and could cost effectively aid in serially monitoring complete remission for continue response or biochemical relapse.


Assuntos
Glicoproteínas/sangue , Mieloma Múltiplo/sangue , Mieloma Múltiplo/terapia , Transplante de Células-Tronco , Adulto , Idoso , Autoenxertos , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Indução de Remissão , Estudos Retrospectivos
3.
Ecology ; 98(7): 1787-1796, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28369822

RESUMO

To improve understanding of the complex and variable patterns of predator foraging behavior in natural systems, it is critical to determine how density-dependent predation and predator hunting success are mediated by alternate prey or predator interference. Despite considerable theory and debate seeking to place predator-prey interactions in a more realistic context, few empirical studies have quantified the role of alternate prey or intraspecific interactions on predator-prey dynamics. We assessed functional responses of two similarly sized, sympatric carnivores, lynx (Lynx canadensis) and coyotes (Canis latrans), foraging on common primary (snowshoe hares; Lepus americanus) and alternate (red squirrels; Tamiasciurus hudsonicus) prey in a natural system. Lynx exhibited a hyperbolic prey-dependent response to changes in hare density, which is characteristic of predators relying primarily on a single prey species. In contrast, the lynx-squirrel response was found to be linear ratio dependent, or inversely dependent on hare density. The coyote-hare and coyote-squirrel interactions also were linear and influenced by predator density. We explain these novel results by apparent use of spatial and temporal refuges by prey, and the likelihood that predators commonly experience interference and lack of satiation when foraging. Our study provides empirical support from a natural predator-prey system that (1) predation rate may not be limited at high prey densities when prey are small or rarely captured; (2) interference competition may influence the predator functional response; and (3) predator interference has a variable role across different prey types. Ultimately, distinct functional responses of predators to different prey types illustrates the complexity associated with predator-prey interactions in natural systems and highlights the need to investigate predator behavior and predation rate in relation to the broader ecological community.


Assuntos
Ecossistema , Comportamento Predatório , Animais , Coiotes , Lebres , Lynx , Dinâmica Populacional , Sciuridae
4.
Respir Res ; 16: 96, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26243289

RESUMO

BACKGROUND: Alpha-1-antitrypsin (A1AT) deficiency disease results from mutations in the A1AT gene. Controversy exists in regards to treatment of heterozygous carriers of the S and Z deficiency alleles. Quantitation of allelic expression has not been possible with standard laboratory methods. Here we show that the recently described method for liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis of A1AT tryptic peptides can differentiate between mutated (S and Z) and wild-type (non-S and non-Z) proteins allowing for quantitation of circulating allelic expression in heterozygous patients. METHODS: Serum (244 M/M, 61 M/Z, and 63 M/S) was combined with isotopically labeled peptide standards, digested with trypsin, and quantitated by LC-MS/MS. Total and allele-specific A1AT quantitation was performed by comparison of peptide peak height ratios to a standard curve for each peptide. Linear regression was used to compare results and central 95(th) percentile intervals were calculated using parametric analysis. RESULTS: Quantitation of circulating wild-type A1AT based on the proteotypic and allelic (non-S and non-Z) peptides was validated in M/M patients. Proteotypic peptide concentrations correlated linearly with quantitation by non-Z and non-S peptides [slopes (Spearman correlation coefficient) of 1.09 (0.89) and 0.98 (0.80), respectively]. Allele-specific quantitation showed significant differences in wild-type protein expression in M/Z and M/S patients. Although average total A1AT concentration was lower for M/Z patients, the percentage of wild-type protein in M/Z patients was significantly higher at 82 % (55- > 95 %) compared to 63 % (43-83 %) for M/S heterozygotes. In a cohort of M/Z patients with sufficient total A1AT (≥80 mg/dL), half had insufficient wild-type protein that could have clinical implications for pulmonary dysfunction. CONCLUSIONS: For the first time, a method to quantitate A1AT allele protein expression is described. Given the wide range of circulating wild-type protein observed in heterozygous patients, this method has the potential to reveal correlations between allele concentration and development and/or severity of clinical symptoms.


Assuntos
Alelos , Heterozigoto , Deficiência de alfa 1-Antitripsina/sangue , alfa 1-Antitripsina/sangue , Biomarcadores/sangue , Cromatografia Líquida/métodos , Feminino , Humanos , Masculino , Espectrometria de Massas em Tandem/métodos , alfa 1-Antitripsina/genética , Deficiência de alfa 1-Antitripsina/genética
5.
Conserv Physiol ; 2(1): cou044, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27293665

RESUMO

Non-invasive monitoring of wild felid reproductive states is important, given that many species reproduce poorly in captivity. Despite extensive work in faecal hormone analysis in felids, continued development of techniques is necessary, particularly with wild populations. In this study, our aims were as follows: (i) biochemical validation of enzyme immunoassays for estrogen, testosterone and progesterone in Canada lynx and domestic cat hair extracts; (ii) assessment of the use of hair reproductive hormones to differentiate between reproductive states (intact, estrus, pregnant and spayed/neutered), using domestic cats as a model; and (iii) assessment of the use of hair reproductive hormones to differentiate between age and sex, accounting for potential regional variability in wild lynx populations. Analysis of hair hormone levels showed prospective value in detecting pregnancy states, with pregnant domestic cats having higher levels of progesterone than spayed females. However, intact and pregnant cats did not differ in progesterone levels. Yet, two female domestic cats had higher levels of hair progesterone following a 38-day oral progestin treatment, perhaps providing a preliminary pharmacological validation of the method. Estrogen and testosterone did not differ statistically according to reproductive states of domestic cats, although intact males had higher levels of hair testosterone than neutered males. When we applied these techniques to lynx fur, we determined that hormone levels were not sufficiently precise to differentiate age classes. Hair reproductive hormone ratios differed between sexes, with the estrogen-to-progesterone ratio demonstrating the highest accuracy in differentiating males from females. Hair hormone levels differed regionally for wild lynx, indicating that spatial variability should be a consideration in wildlife hormone studies spanning large spatial scales. We conclude that use of hair hormone analysis by enzyme immunoassay may hold promise for differentiating sex in felids, but the technique will require further refinement and validation before it can be applied broadly and reliably.

6.
Gen Comp Endocrinol ; 194: 162-7, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24080086

RESUMO

Land use changes are a significant factor influencing the decline of felid populations. However, additional research is needed to better understand how these factors influence populations in the wild. Hormone analysis can provide valuable information on the basic physiology and overall health of an animal, and enzyme immunoassays (EIA) are generally used for hair hormone analysis but must first be validated for the substrate of choice and species of interest. To date, hormone assays from hair have not been validated for Felidae, despite that the method holds considerable promise for non-invasive sampling of free-ranging animals. We sought to: (1) evaluate whether increased adrenocorticotrophin hormone (ACTH) during the period of hair growth results in elevated hair cortisol; (2) validate the enzyme immunoassay used; and (3) identify any variations in hair cortisol between age, sex and body regions, using Canada lynx. We quantified hair cortisol concentrations in captive animals through an ACTH challenge and collected samples from legally harvested lynx to compare variability between body regions. An EIA was validated for the analysis of hair cortisol. Lynx (n=3) had a qualitative increase in hair cortisol concentration following an ACTH challenge in captive animals (20 IU/kg of body weight weekly for 5 weeks), thereby supporting the use of an EIA to quantify cortisol values in hair. Based on our analysis of sampled lynx pelts, we found that hair cortisol did not vary between age and sex, but varied within the foot/leg region to a greater extent than between individuals. We recommend that future studies identify a standardized location for hair cortisol sampling.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Hidrocortisona/metabolismo , Lynx/metabolismo , Animais , Canadá , Feminino , Cabelo/química , Masculino , Estresse Fisiológico/fisiologia
7.
Oecologia ; 152(1): 162-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17216211

RESUMO

Predators have been shown to alter the timing of switch points between life history stages, but few studies have addressed switch point plasticity in prey exposed simultaneously to conflicting predation pressure. We tested hatching responses of green frog (Rana clamitans) embryos subject to perceived predation risk from chemical cues released by two stage-specific predators, predicting that these predators would elicit: (1) directional hatching responses when presented independently, and (2) intermediate phenotypic responses when presented simultaneously. R. clamitans embryos in outdoor exclosures were exposed to cues from an egg predator (freshwater leeches; Nephelopsis obscura), a larval predator (dragonfly nymphs, Aeschna canadensis), and both predators in a 2 x 2 factorial experiment, and changes in hatchling size, hatchling developmental stage, and hatching time were compared to those for control embryos. Leeches alone induced embryos to hatch at a smaller size and an earlier developmental stage than controls, while dragonfly nymphs elicited a delay in egg hatching time that was associated with larger size and later developmental stage at hatching. Embryos failed to respond to simultaneous exposure to both predators, implying that responses to each occurred concurrently and were therefore dampened. Our results indicate that prey under threat from conflicting predators may manifest intermediate defensive phenotypes. Such intermediate responses may result in elevated rates of prey mortality with possible consequences at the population level.


Assuntos
Adaptação Fisiológica , Cadeia Alimentar , Ranidae/embriologia , Animais , Sinais (Psicologia) , Embrião não Mamífero/fisiologia , Desenvolvimento Embrionário , Insetos/fisiologia , Sanguessugas/fisiologia , Ninfa/fisiologia , Fenótipo , Comportamento Predatório , Ranidae/crescimento & desenvolvimento , Ranidae/fisiologia , Risco
10.
Poult Sci ; 79(11): 1536-42, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11092321

RESUMO

A model was developed to examine the proliferation of Aspergillus fumigatus on the air cell membrane of broiler hatching eggs and to assay the effectiveness of fungal control strategies that may be used in conjunction with late embryonic egg injection. Egg yolk was identified as the nutritive media required to sustain fungal growth. Incubation was required to predispose the egg to fungal infection by allowing the yolk to come into contact with the air cell membrane. Infertile eggs and eggs containing embryos that died before 4 d of incubation (early-dead) that had been subsequently incubated for 9 d or more were equally susceptible to fungal infection. In order to evaluate potential methods of control, these eggs were punched through the blunt end of the shell with a 16-gauge needle, placed into forced-air incubators (hatchers), and exposed to air-dispersed pure cultures of A. fumigatus. The frequency of eggs exhibiting mold growth on the air cell membrane 72 h after exposure was subjected to a Chi-square analysis model. The effect of egg position within an incubator flat in relationship to the A. fumigatus source culture, the variation between flats (levels) within a given hatcher, the variation between hatchers, and the variation between replicate trials were measured and found to be potential sources of experimental error that must be minimized in order to accept the results of an evaluation. A statistically valid model was developed that can be used to evaluate various types of fungicidal treatments of hatching eggs and their relative efficacy in association with egg injection.


Assuntos
Aspergillus fumigatus/crescimento & desenvolvimento , Embrião de Galinha/microbiologia , Animais , Casca de Ovo , Gema de Ovo/microbiologia , Perda do Embrião , Concentração de Íons de Hidrogênio , Morfogênese
13.
J Dent Hyg ; 73(1): 22-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10634118

RESUMO

PURPOSE: The purpose of this study was to assess dental hygienists' general knowledge of menopause and its possible oral manifestations. Demographic descriptors, including education level, course work, and menopausal status, were examined to determine their influence on knowledge levels. METHOD: A 27-item, self-administered survey was mailed to a random sample of Connecticut dental hygienists. Frequency distributions and inferential statistics (ANOVA, t-test) were used for data analysis. RESULTS: Fifty-four percent of respondents scored 75 percent or higher in general knowledge about menopause. Seven percent scored the same about its oral effects. Educational level and dental hygiene college curricula influenced the oral effect scores. Dental hygienists with bachelor degrees exhibited more knowledge than those with certificate/associate degrees. Those who had taken a college course on the oral effects of menopause had more knowledge than those who had not. CONCLUSION: The findings suggest that dental hygienists need more education about menopause and its related oral conditions. Those with additional knowledge might be more able to provide comprehensive care to menopausal and post-menopausal dental patients. Future research using larger sample sizes may enhance the education of dental hygienists in this area.


Assuntos
Higienistas Dentários , Menopausa/fisiologia , Doenças da Boca/etiologia , Análise de Variância , Higienistas Dentários/educação , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pessoa de Meia-Idade , Inquéritos e Questionários
14.
Biochemistry ; 37(20): 7194-202, 1998 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-9585531

RESUMO

The three-dimensional structures of five mutants of toxic shock syndrome toxin-1 (TSST-1) have been determined. These mutations are in the long central alpha helix and are useful in mapping portions of TSST-1 involved in superantigenicity and lethality. The T128A, H135A, Q139K, and I140T mutations appear to reduce superantigenicity by altering the properties of the T-cell receptor interaction surface. The Q136A mutation is at a largely buried site and causes a dramatic change in the conformation of the beta7-beta9 loop which covers the back of the central alpha helix. As this mutation has the unique ability to reduce the toxin's lethality in rabbits while retaining its superantigenicity, it raises the possibility that this rear loop mediates the ability of TSST-1 to induce lethality and suggests a route for producing nonlethal toxins for therapeutic development.


Assuntos
Toxinas Bacterianas , Enterotoxinas/química , Enterotoxinas/genética , Mutação , Staphylococcus aureus/imunologia , Superantígenos/toxicidade , Alanina/genética , Animais , Cristalografia por Raios X , Enterotoxinas/toxicidade , Glutamina/genética , Histidina/genética , Humanos , Lisina/genética , Camundongos , Modelos Moleculares , Coelhos , Staphylococcus aureus/química , Staphylococcus aureus/genética , Superantígenos/química , Superantígenos/genética , Treonina/genética
16.
Fertil Steril ; 69(1): 41-5, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9457930

RESUMO

OBJECTIVE: To test the hypothesis that IVF-ET pregnancy rates (PRs) for patients with tubal factor infertility are decreased in patients with hydrosalpinges and that surgical correction reverses this effect. DESIGN: Retrospective chart review. SETTING: Private practice IVF-ET program. PATIENT(S): Patients (n = 160) undergoing 238 cycles of IVF-ET were stratified into groups based on the presence of hydrosalpinges and whether surgical correction had been performed. Patients >39 years old and patients with male factor infertility were excluded from the study. INTERVENTION(S): Patients with hydrosalpinges were offered surgical correction. MAIN OUTCOME MEASURE(S): Clinical pregnancy defined by an intrauterine gestational sac. RESULT(S): Patients with hydrosalpinges had significantly decreased implantation rates and PRs per transfer (2.8% and 8.5%, respectively) than patients with tubal factor infertility but without hydrosalpinges (15.7% and 38.6%). Surgical correction improved implantation rates and PRs in patients with prior failed cycles (16.1% and 37.5%) and in patients undergoing surgery before IVF-ET (21.8% and 51.7%). The type of surgery performed did not affect success rates in the small number of patients evaluated. CONCLUSION(S): The presence of a hydrosalpinx during an IVF-ET cycle results in significant decreases in implantation rates and PRs. Surgical treatment of hydrosalpinges before IVF-ET cycles improves implantation rates and PRs.


Assuntos
Doenças das Tubas Uterinas/fisiopatologia , Doenças das Tubas Uterinas/cirurgia , Fertilização In Vitro , Taxa de Gravidez , Adulto , Implantação do Embrião , Doenças das Tubas Uterinas/complicações , Feminino , Humanos , Infertilidade Feminina/etiologia , Masculino , Registros Médicos , Gravidez , Estudos Retrospectivos , Salpingostomia
17.
Poult Sci ; 76(10): 1379-86, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9316113

RESUMO

This report examines optimal culture conditions necessary for accurate and sensitive quantification of chicken T Cell Growth Factor (TCGF) activity. With this bioassay, TCGF is quantified by measuring its ability to cause proliferation of splenocytes prestimulated with mitogen. Proliferation is quantified by determining the optical density (OD) or "signal" of test samples in microtiter wells by measuring the incorporation of tetrazolium salt by live cells. To optimize assay conditions, systematic evaluation of the effects of cell culture variables was carried out with the constant aim of increasing signal to noise ratio in the assay. Higher signal to noise ratios were found when using Dulbecco's Modified Eagle's Medium (DMEM) rather than Roswell Park Memorial Institute Medium (RPMI) for basal tissue culture media containing the same supplements. The addition of lipid supplement to the assay system not only increased the proliferation signal, but also decreased the background OD. Incubation temperatures of 41 C rather than 37 C for both the mitogen prestimulation and proliferation phases of the assay also resulted in a higher signal to noise ratio. While incorporating the optimal experimental conditions, a finalized assay procedure employing test sample normalization with an internal assay standard was tested for accuracy. The assay can accurately detect 2 to 15 U/mL of TCGF activity. The within-assay variation ranged from 2 to 13% and the between-assay variation ranged from 11 to 22% depending upon the TCGF preparation being tested. The excellent reproducibility of this assay has facilitated investigations of TCGF production, processing, and purification.


Assuntos
Galinhas/fisiologia , Interleucina-2/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/imunologia , Baço/citologia , Animais , Células Cultivadas , Concanavalina A/farmacologia , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Citometria de Fluxo/métodos , Citometria de Fluxo/veterinária , Imunoglobulina M/análise , Lipídeos/farmacologia , Ativação Linfocitária/fisiologia , Linfócitos/química , Linfócitos/efeitos dos fármacos , Manose/farmacologia , Mitógenos/farmacologia , Receptores de Interleucina-2/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Baço/efeitos dos fármacos , Baço/fisiologia , Temperatura , Fatores de Tempo
19.
J Pediatr Hematol Oncol ; 19(1): 82-5, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9065725

RESUMO

PURPOSE: The purpose of this report is to emphasize the importance of occurrence of Streptococcus mitis meningitis in febrile neutropenic children with hematopoietic malignancy. PATIENTS AND METHODS: Symptoms of meningitis and sepsis (fever, headache, changes in mental status) were seen in three patients who were severely neutropenic and undergoing cytotoxic chemotherapy for CNS relapse of their underlying malignancy (acute lymphoblastic leukemia (ALL), n = 2; Burkitt's lymphoma, n = 1). Chemotherapy had included cytosine arabinoside administered 7-14 days prior to presenting with sepsis and meningitis. All three patients had buccal mucositis or sinusitis. Blood cultures and CSF cultures showed S. mitis resistant to penicillin but sensitive to vancomycin. Vancomycin, at a dosage of 60 mg/kg/day to maximize CNS levels of antibiotic, was administered to all three children. RESULTS: Two of the patients recovered from S. mitis meningitis; recovery was associated with an improvement in their peripheral granulocyte counts. One patient, who remained neutropenic, died despite being treated with both intravenous and intraventricular vancomycin. CONCLUSION: Physicians caring for patients who are neutropenic and febrile need to be aware of the risk of meningitis occurring with S. mitis sepsis. Early treatment with high dosages of vancomycin (60 mg/kg/day) and an attempt to limit the duration of neutropenia are important factors in the outcome of such patients.


Assuntos
Bacteriemia/etiologia , Linfoma de Burkitt/complicações , Meningites Bacterianas/etiologia , Neutropenia/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Infecções Estreptocócicas/etiologia , Streptococcus/isolamento & purificação , Bacteriemia/tratamento farmacológico , Linfoma de Burkitt/sangue , Criança , Feminino , Humanos , Masculino , Meningites Bacterianas/tratamento farmacológico , Resistência às Penicilinas , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Infecções Estreptocócicas/tratamento farmacológico
20.
Infect Immun ; 64(1): 371-4, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8557369

RESUMO

Toxic shock syndrome toxin 1 (TSST-1) contains a long central alpha helix that forms the base of two grooves on opposite sides of the molecule. Previous studies indicated that residues 132, 135, and 140 along the back of the central alpha helix are important in the biological activities. We made mutations of additional central alpha-helix residues exposed along this groove on the back of TSST-1. The proteins were purified, shown not to have gross alteration in structure, and tested for both superantigenicity and ability to elicit lethal TSS, using the superantigenicity, likely to because of alteration in T-cell receptor binding. Mutants H135A, Q136A, and E132K/ Q136K lost the ability to induce lethal TSS. The mutant Q136A was most increasing because it was superantigenic, yet nonlethal.


Assuntos
Toxinas Bacterianas , Enterotoxinas/farmacologia , Staphylococcus aureus/imunologia , Superantígenos/farmacologia , Animais , Análise Mutacional de DNA , Relação Dose-Resposta a Droga , Enterotoxinas/genética , Ativação Linfocitária/efeitos dos fármacos , Modelos Moleculares , Mutagênese Sítio-Dirigida , Estrutura Secundária de Proteína , Coelhos , Choque Séptico , Relação Estrutura-Atividade , Superantígenos/genética
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