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1.
Reproduction ; 166(5): 337-348, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37672361

RESUMO

In brief: The first week of gestation is a period of major pregnancy loss in cattle, this study reveals that the male plays a key role in regulating embryonic development during this time. Abstract: The impact of sire on preimplantation embryonic development in cattle remains poorly understood. This study evaluated differences in embryos produced in vitro from sires with varying capacities to produce blastocysts. Sires classified as high (HP) and low performing (LP) based on their ability to produce embryos were used to better understand how sire regulates embryonic development. By monitoring development, it was determined that the most common arrest stage was the five- to six-cell stage. Embryos (four to six cells) from HP and LP sires were then analyzed for autophagic activity, where embryos for LP sires exhibited increased autophagy than HP-derived embryos. Transcriptome analysis of four-cell embryos found that embryos from LP sires might have issues in sperm mitochondrial clearance, histone retention, and DNA damage, while HP sires had increased expression of genes involved in transcription, chromosome segregation, and cell division. In conclusion, LP sires had an increased proportion of embryos arresting at the five- to six-cell stage, and these embryos had higher rates of cellular stress due to paternal contributions from the spermatozoon.


Assuntos
Sêmen , Transcriptoma , Gravidez , Feminino , Masculino , Bovinos , Animais , Embrião de Mamíferos , Desenvolvimento Embrionário/genética , Blastocisto
2.
Biol Reprod ; 105(6): 1577-1590, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34608481

RESUMO

Establishment and maintenance of pregnancy in the pig is a complex process that relies on conceptus regulation of the maternal proinflammatory response to endometrial attachment. Following elongation, pig conceptuses secrete interferon gamma (IFNG) during attachment to the endometrial luminal epithelium. The objective here was to determine if conceptus production of IFNG is important for early development and establishment of pregnancy. CRISPR/Cas9 gene editing and somatic cell nuclear transfer technologies were used to create an IFNG loss-of-function study in pigs. Wild-type (IFNG+/+) and null (IFNG-/-) fibroblast cells were used to create embryos through somatic cell nuclear transfer. IFNG expression was not detected in IFNG-/- conceptuses on either day 15 or day 17 of pregnancy. Ablation of conceptus IFNG production resulted in the reduction of stromal CD3+ and mast cells, which localized to the site of conceptus attachment on day 15. The uteri of recipients with IFNG-/- conceptuses were inflamed, hyperemic and there was an abundance of erythrocytes in the uterine lumen associated with the degenerating conceptuses. The endometrial stromal extracellular matrix was altered in the IFNG-/- embryo pregnancies and there was an increased endometrial mRNA levels for collagen XVII (COL17A1), matrilin 1 (MATN1), secreted phosphoprotein 1 (SPP1), and cysteine-rich secretory protein 3 (CRISP3), which are involved with repair and remodeling of the extracellular matrix. These results indicate conceptus IFNG production is essential in modulating the endometrial proinflammatory response for conceptus attachment and survival in pigs.


Assuntos
Embrião de Mamíferos/metabolismo , Interferon gama/metabolismo , Prenhez/metabolismo , Sus scrofa/embriologia , Animais , Desenvolvimento Embrionário , Feminino , Gravidez
3.
Biol Reprod ; 102(2): 475-488, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-31616930

RESUMO

Pig conceptuses secrete estrogens (E2), interleukin 1 beta 2 (IL1B2), and prostaglandins (PGs) during the period of rapid trophoblast elongation and establishment of pregnancy. Previous studies established that IL1B2 is essential for rapid conceptus elongation, whereas E2 is not essential for conceptus elongation or early maintenance of the corpora lutea. The objective of the present study was to determine if conceptus expression of prostaglandin-endoperoxide synthase 2 (PTGS2) and release of PG are important for early development and establishment of pregnancy. To understand the role of PTGS2 in conceptus elongation and pregnancy establishment, a loss-of-function study was conducted by editing PTGS2 using CRISPR/Cas9 technology. Wild-type (PTGS2+/+) and null (PTGS2-/-) fibroblast cells were used to create embryos through somatic cell nuclear transfer. Immunolocalization of PTGS2 and PG production was absent in cultured PTGS2-/- blastocysts on day 7. PTGS2+/+ and PTGS2-/- blastocysts were transferred into surrogate gilts, and the reproductive tracts were collected on either days 14, 17, or 35 of pregnancy. After flushing the uterus on days 14 and 17, filamentous conceptuses were cultured for 3 h to determine PG production. Conceptus release of total PG, prostaglandin F2⍺ (PGF2α), and PGE in culture media was lower with PTGS2-/- conceptuses compared to PTGS2+/+ conceptuses. However, the total PG, PGF2α, and PGE content in the uterine flushings was not different. PTGS2-/- conceptus surrogates allowed to continue pregnancy were maintained beyond 30 days of gestation. These results indicate that pig conceptus PTGS2 is not essential for early development and establishment of pregnancy in the pig.


Assuntos
Blastocisto/metabolismo , Ciclo-Oxigenase 2/metabolismo , Implantação do Embrião/fisiologia , Desenvolvimento Embrionário/fisiologia , Endométrio/metabolismo , Animais , Animais Geneticamente Modificados , Sistemas CRISPR-Cas , Ciclo-Oxigenase 2/genética , Dinoprosta/metabolismo , Dinoprostona/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Transferência Nuclear , Gravidez , Suínos
4.
Sci Rep ; 12(1): 10540, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35732675

RESUMO

In vitro production (IVP) of embryos in cattle can result in large/abnormal offspring syndrome (LOS/AOS) which is characterized by macrosomia. LOS can cause dystocia and lead to the death of dam and calf. Currently, no test exists to identify LOS pregnancies. We hypothesized that fetal ultrasonography and/or maternal blood markers are useful to identify LOS. Bovine fetuses were generated by artificial insemination (control) or IVP. Fetal ultrasonographies were taken on gestation D55 (D55) and fetal collections performed on D56 or D105 (gestation in cattle ≈ D280). IVP fetuses weighing ≥ 97 percentile of the control weight were considered LOS. Ultrasonography results show that the product of six D55 measurements can be used to identify extreme cases of LOS. To determine whether maternal blood can be used to identify LOS, leukocyte mRNA from 23 females was sequenced. Unsupervised hierarchical clustering grouped the transcriptomes of the two females carrying the two largest LOS fetuses. Comparison of the leukocyte transcriptomes of these two females to the transcriptome of all other females identified several misregulated transcripts on gestation D55 and D105 with LOC783838 and PCDH1 being misregulated at both time-points. Together our data suggest that LOS is identifiable during pregnancy in cattle.


Assuntos
Perfilação da Expressão Gênica , Inseminação Artificial , Animais , Bovinos , Feminino , Feto , Inseminação Artificial/veterinária , Gravidez , Ultrassonografia Pré-Natal
5.
J Food Sci ; 86(11): 4901-4913, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34636050

RESUMO

Eight different roast profiles for each of the three origins of cacao were prepared and made into unsweetened chocolate based upon an I-Optimal response-surface design for minimizing prediction variance. Quantitative chemical analysis of all chocolate treatments was performed with HPLC-DAD on six important bitter compounds (i.e., theobromine, caffeine, epicatechin, catechin, procyanidin B2, and cyclo(Proline-Valine)). Least-squares linear modeling was then performed. Using derived linear models, response-surface contour plots were produced to show predicted changes in the six bitter compounds over the entire experimental region. Significant and large decreases in concentration of epicatechin and procyanidin B2 were observed as roasting progressed, whereas for catechin and cyclo(Proline-Valine), significant increases were observed. Small yet significant theobromine and caffeine concentration increases were also observed with roasting, likely due to moisture loss. Some significant differences were also found between the cacao origins for all bitter compound concentrations except for cyclo(Proline-Valine), suggesting the importance of a survey encompassing a greater number of cacao origins in the future to obtain a more complete picture of the variation in bitter compounds in cacao due to origin. PRACTICAL APPLICATION: This research describes how roasting can be used to alter the concentration of bitter and sometimes astringent chemicals for several origins of cacao, which may be used to improve the sensory characteristics of dark chocolate.


Assuntos
Cacau , Chocolate , Cafeína , Chocolate/análise , Cromatografia Líquida de Alta Pressão , Paladar
6.
PLoS One ; 16(12): e0260123, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34882691

RESUMO

Serum supplementation during bovine embryo culture has been demonstrated to promote cell proliferation and preimplantation embryo development. However, these desirable outcomes, have been associated with gene expression alterations of pathways involved in macroautophagy, growth, and development at the blastocyst stage, as well as with developmental anomalies such as fetal overgrowth and placental malformations. In order to start dissecting the molecular pathways by which serum supplementation of the culture medium during the preimplantation stage promotes developmental abnormalities, we examined blastocyst morphometry, inner cell mass and trophectoderm cell allocations, macroautophagy, and endoplasmic reticulum stress. On day 5 post-insemination, > 16 cells embryos were selected and cultured in medium containing 10% serum or left as controls. Embryo diameter, inner cell mass and trophectoderm cell number, and macroautophagy were measured on day 8 blastocysts (BL) and expanded blastocysts (XBL). On day 5 and day 8, we assessed transcript level of the ER stress markers HSPA5, ATF4, MTHFD2, and SHMT2 as well as XBP1 splicing (a marker of the unfolded protein response). Serum increased diameter and proliferation of embryos when compared to the no-serum group. In addition, serum increased macroautophagy of BL when compared to controls, while the opposite was true for XBL. None of the genes analyzed was differentially expressed at any stage, except that serum decreased HSPA5 in day 5 > 16 cells stage embryos. XBP1 splicing was decreased in BL when compared to XBL, but only in the serum group. Our data suggest that serum rescues delayed embryos by alleviating endoplasmic reticulum stress and promotes development of advanced embryos by decreasing macroautophagy.


Assuntos
Meios de Cultura/farmacologia , Embrião de Mamíferos/citologia , Marcadores Genéticos/efeitos dos fármacos , Soro/química , Animais , Blastocisto , Bovinos , Proliferação de Células/efeitos dos fármacos , Meios de Cultura/química , Técnicas de Cultura Embrionária , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Estresse do Retículo Endoplasmático , Regulação da Expressão Gênica no Desenvolvimento , Macroautofagia/efeitos dos fármacos
7.
Int Arch Allergy Immunol ; 150(1): 43-50, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19339801

RESUMO

BACKGROUND: Racemic (R,S)-albuterol is a 1:1 mixture of an R-enantiomer which has bronchodilatory and anti-inflammatory effects, and an S-enantiomer which is associated with increased airway hyperreactivity and proinflammatory effects. Proinflammatory effects of regularly inhalated and S-albuterol have not been studied in a whole-animal model. We hypothesized that regular administration of R,S-albuterol or S-albuterol, but not R-albuterol, would induce airway inflammation in healthy and asthmatic cats. METHODS: Six healthy and 5 experimentally asthmatic cats were randomized to receive inhaled R,S-albuterol, S-albuterol, R-albuterol, or placebo (saline) twice daily for 2 weeks, followed by a 6-week washout before crossover to the next treatment. Bronchoalveolar lavage fluid was collected for cell counts and cytokine analysis prior to and at the end of each 2-week treatment. RESULTS: Healthy and asthmatic cats receiving R,S- and S-albuterol had higher total lavage cell numbers (p = 0.04 and p = 0.02, respectively) than those receiving R-albuterol and placebo. The number of lavage eosinophils and the TNF-alpha bioactivity was higher in asthmatic cats receiving R,S- and S-albuterol compared with those receiving the other treatments (p = 0.03 and p = 0.004, respectively). In healthy cats, the number of lavage neutrophils was higher when they received R,S- and S-albuterol compared with other treatments (p = 0.04). CONCLUSION: Airway inflammation is induced in both healthy and asthmatic cats with regular inhalation of racemic and S-albuterol, but not with R-albuterol.


Assuntos
Albuterol/efeitos adversos , Asma/tratamento farmacológico , Broncodilatadores/efeitos adversos , Pneumonia/induzido quimicamente , Albuterol/química , Animais , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Broncodilatadores/química , Gatos , Citocinas/análise , Citocinas/efeitos dos fármacos , Masculino , Estereoisomerismo
8.
Vet Immunol Immunopathol ; 129(1-2): 49-56, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19144412

RESUMO

Rush immunotherapy (RIT) is effective for the treatment of experimental feline allergic asthma. In humans, the safety profile of immunotherapy is improved by delivering allergen by a mucosal route. We hypothesized that mucosal (intranasal) RIT would have similar efficacy to subcutaneous RIT with improved safety. Twelve cats sensitized and challenged with Bermuda grass allergen (BGA) were randomized to receive subcutaneous (SC) or intranasal (IN) RIT. Increasing doses of BGA (20-200 microg) were administered over 24h followed by 200 microg BGA weekly as maintenance. Adverse reactions were recorded. Clinical respiratory scores after BGA aerosol challenge, bronchoalveolar lavage fluid (BALF) % eosinophils, and cytokine concentrations were measured before RIT (day 1) and at months 1, 3 and 6 (M1, M3, M6). More adverse events were recorded with SC RIT (n=12) compared with IN RIT (n=6). Respiratory scores were lower by M6 compared with D1 in both the groups. The % BALF eosinophils declined significantly after RIT for both groups (mean+/-SEM, SC RIT D1 62+/-12, M6 9+/-4; IN RIT D1 54+/-9, M6 14+/-6). The BALF IL-4:IFN-gamma ratio significantly decreased over time in the IN RIT group (mean+/-SEM, D1 2.4+/-0.2, M6 1.0+/-0.2). While both protocols decreased eosinophilic airway inflammation, the SC RIT protocol did not cause life-threatening adverse events and demonstrated more consistent resolution of clinical signs after allergen challenge. Either protocol could be considered for the treatment of feline allergic asthma.


Assuntos
Alérgenos/administração & dosagem , Asma/veterinária , Doenças do Gato/terapia , Dessensibilização Imunológica/veterinária , Administração Intranasal , Animais , Asma/imunologia , Asma/terapia , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Doenças do Gato/imunologia , Gatos , Contagem de Células , Cynodon/imunologia , Citocinas/imunologia , Dessensibilização Imunológica/efeitos adversos , Dessensibilização Imunológica/métodos , Eosinófilos/imunologia , Feminino , Injeções Subcutâneas , Masculino , Distribuição Aleatória , Organismos Livres de Patógenos Específicos
9.
Biometrics ; 64(3): 673-684, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18047538

RESUMO

It is widely believed that risks of many complex diseases are determined by genetic susceptibilities, environmental exposures, and their interaction. Chatterjee and Carroll (2005, Biometrika 92, 399-418) developed an efficient retrospective maximum-likelihood method for analysis of case-control studies that exploits an assumption of gene-environment independence and leaves the distribution of the environmental covariates to be completely nonparametric. Spinka, Carroll, and Chatterjee (2005, Genetic Epidemiology 29, 108-127) extended this approach to studies where certain types of genetic information, such as haplotype phases, may be missing on some subjects. We further extend this approach to situations when some of the environmental exposures are measured with error. Using a polychotomous logistic regression model, we allow disease status to have K+ 1 levels. We propose use of a pseudolikelihood and a related EM algorithm for parameter estimation. We prove consistency and derive the resulting asymptotic covariance matrix of parameter estimates when the variance of the measurement error is known and when it is estimated using replications. Inferences with measurement error corrections are complicated by the fact that the Wald test often behaves poorly in the presence of large amounts of measurement error. The likelihood-ratio (LR) techniques are known to be a good alternative. However, the LR tests are not technically correct in this setting because the likelihood function is based on an incorrect model, i.e., a prospective model in a retrospective sampling scheme. We corrected standard asymptotic results to account for the fact that the LR test is based on a likelihood-type function. The performance of the proposed method is illustrated using simulation studies emphasizing the case when genetic information is in the form of haplotypes and missing data arises from haplotype-phase ambiguity. An application of our method is illustrated using a population-based case-control study of the association between calcium intake and the risk of colorectal adenoma.


Assuntos
Exposição Ambiental , Haplótipos , Análise de Regressão , Adenoma/etiologia , Adenoma/genética , Algoritmos , Biometria , Cálcio da Dieta/administração & dosagem , Estudos de Casos e Controles , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/genética , Exposição Ambiental/estatística & dados numéricos , Predisposição Genética para Doença , Genótipo , Humanos , Funções Verossimilhança , Modelos Logísticos , Modelos Estatísticos , Estudos Retrospectivos , Fatores de Risco
10.
Vet Immunol Immunopathol ; 121(3-4): 241-50, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17981343

RESUMO

Allergic asthma is driven by relative overexpression of Th2 cell-derived cytokines in response to aeroallergens. In independent studies, both allergen-specific rush immunotherapy (RIT) and CpG oligodeoxynucleotides (ODN) showed promise in blunting eosinophilic inflammation in a model of feline allergic asthma. We hypothesized that RIT using allergen and CpG ODN would work synergistically to dampen the asthmatic phenotype in experimentally asthmatic cats. Twelve cats with asthma induced using Bermuda grass allergen (BGA) were studied. Of these, six were administered adjuvanted BGA RIT using CpG ODN #2142; six were administered placebo (saline) RIT and later crossed over to adjuvanted RIT. Over 2 days, subcutaneous CpG ODN (0.5ng/kg) with BGA (increasing doses every 2h from 20 to 200microg) was administered. Adverse events were recorded and compared with historical controls. Percentage of eosinophils in bronchoalveolar lavage fluid (BALF), % peripheral CD4+CD25+ T regulatory cells (Tregs), lymphocyte proliferation in response to ConA, and cytokine concentrations in BALF were measured over 2 months. Group mean BALF % eosinophils for the adjuvanted RIT cats were significantly lower at week 1 and month 1 (p=0.03 for both), and marginally significantly lower at month 2 (p=0.09) compared with placebo RIT cats. By the end of the study, 8/12 treated cats had BALF % eosinophils within the reference range for healthy cats. Adjuvanted RIT, but not placebo RIT, cats had significant decreases in the ConA stimulation index over time (p=0.05). BALF IL-4 concentrations were significantly higher at week 1 in adjuvanted RIT cats compared with baseline and month 2, and also with placebo RIT cats at week 1. No significant differences were detected between treatments or over time for IL-10 or IFN-gamma concentrations in BALF or for %Tregs cells in peripheral blood. Adjuvanted RIT using CpG ODN in experimental feline asthma dampens eosinophilic airway inflammation. Adverse effects associated with adjuvanted RIT were less severe compared with a historical, non-adjuvanted RIT protocol. The exact mechanism(s) by which adjuvanted RIT alters the aberrant allergic immune response were not elucidated in this study.


Assuntos
Asma/veterinária , Doenças do Gato/terapia , Cynodon/imunologia , Dessensibilização Imunológica/veterinária , Oligodesoxirribonucleotídeos/farmacologia , Animais , Asma/imunologia , Asma/terapia , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Doenças do Gato/imunologia , Gatos , Dessensibilização Imunológica/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Eosinófilos/imunologia , Citometria de Fluxo/veterinária , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Linfócitos T Reguladores/imunologia
11.
Am J Vet Res ; 68(11): 1265-71, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17975984

RESUMO

OBJECTIVE: To determine whether oral administration of cyproheptadine or cetirizine blocks the action of serotonin and histamine, respectively, and results in diminished eosinophilic airway inflammation in cats with experimentally induced asthma. ANIMALS: 9 cats in which asthma was experimentally induced through exposure to Bermuda grass allergen (BGA) during a 3-month period. PROCEDURES: Cats were randomized to receive monotherapy with each of 3 treatments for 1 week: placebo (flour in a gelatin capsule, PO, q 12 h), cyproheptadine (8 mg, PO, q 12 h), or cetirizine (5 mg, PO, q 12 h). A 1-week washout period was allowed to elapse between treatments. Prior to and following each 1-week treatment period, blood and bronchoalveolar lavage fluid (BALF) samples were collected. The percentage of eosinophils in BALF was evaluated to determine treatment efficacy. Serum and BALF BGA-specific immunoglobulin contents and plasma and BALF histamine concentrations were determined via ELISAs. Plasma and BALF serotonin concentrations were measured by use of a fluorometric method. RESULTS: The mean +/- SD percentage of eosinophils in BALF did not differ significantly among treatment groups (placebo, 40 +/- 22%; cyproheptadine, 27 +/- 16%; and cetirizine, 31 +/- 20%). Among the treatment groups, BGA-specific immunoglobulin content and histamine and serotonin concentrations were not significantly different. CONCLUSIONS AND CLINICAL RELEVANCE: In cats with experimentally induced asthma, cyproheptadine and cetirizine were not effective in decreasing airway eosinophilic inflammation or in altering several other measured immunologic variables. Neither cyproheptadine nor cetirizine can be advocated as monotherapy for cats with allergen-induced asthma.


Assuntos
Asma/veterinária , Doenças do Gato/tratamento farmacológico , Cetirizina/farmacologia , Ciproeptadina/farmacologia , Antagonistas não Sedativos dos Receptores H1 da Histamina/farmacologia , Eosinofilia Pulmonar/veterinária , Antagonistas da Serotonina/farmacologia , Animais , Asma/tratamento farmacológico , Asma/imunologia , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Doenças do Gato/imunologia , Gatos , Estudos Cross-Over , Cynodon/imunologia , Eosinófilos/imunologia , Histamina/sangue , Imunoglobulina A/sangue , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Masculino , Eosinofilia Pulmonar/tratamento farmacológico , Eosinofilia Pulmonar/imunologia , Distribuição Aleatória , Serotonina/sangue , Organismos Livres de Patógenos Específicos
12.
Vet Immunol Immunopathol ; 132(1): 46-52, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19819027

RESUMO

Intradermal skin testing (IDST) and allergen-specific IgE determination are used to determine allergen sensitization. In cats, studies have found poor correlation between the two tests. However, these studies were mainly conducted in pet cats sensitized to unknown allergens with unknown dose and duration of exposure. We hypothesized that in an experimental model of allergic sensitization where these variables are controlled, IDST would demonstrate greater sensitivity and specificity than would serum allergen-specific IgE determination. A model of feline asthma employing Bermuda grass allergen (BGA) or house dust mite allergen (HDMA) was used to test the hypothesis. Thirteen cats were assigned to undergo sensitization to BGA, HDMA or saline (placebo). Bronchoalveolar lavage fluid confirmed development of an asthmatic phenotype. Serum collection and IDST were performed on D0, D28 and D50. A portion of serum was pooled, and an aliquot heat inactivated (HI) to destroy IgE. Individual, pooled, and pooled HI samples were used for allergen-specific IgE determination using an Fc epsilon R1 alpha-based ELISA; pooled samples were also analyzed using an enzymoimmunometric assay. Sensitivity (SE), specificity (SP), and positive and negative predictive values (PPV and NPV) were calculated for IDST and for BGA- and HDMA-specific IgE. Combined results for IDST found SE=90.9%, SP=86.7%, PPV=83.3%, and NPV=92.9%. For ELISA-based serum IgE testing, the SE=22.7%, SP=100%, PPV=100% and NPV=63.8%. The enzymoimmunometric assay did not detect sensitizing IgE, but did detect IgE reactivity to a variety of irrelevant allergens (even in HI samples). Sensitivity of IDST was greater than sensitivity of serum IgE measurement supporting use as a screening test for aeroallergens. Both IDST and allergen-specific IgE determination via ELISA were specific; either test can be used to guide selection of allergens for immunotherapy. The enzymoimmunometric assay was unreliable and cannot be recommended.


Assuntos
Alérgenos/imunologia , Asma/sangue , Asma/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Testes Intradérmicos/métodos , Animais , Especificidade de Anticorpos , Asma/patologia , Líquido da Lavagem Broncoalveolar , Gatos , Modelos Animais de Doenças , Feminino , Masculino , Proteínas de Plantas/imunologia , Poaceae/imunologia , Pyroglyphidae/imunologia
13.
Genet Epidemiol ; 29(2): 108-27, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16080203

RESUMO

Case-control studies of unrelated subjects are now widely used to study the role of genetic susceptibility and gene-environment interactions in the etiology of complex diseases. Exploiting an assumption of gene-environment independence, and treating the distribution of environmental exposures as completely nonparametric, Chatterjee and Carroll recently developed an efficient retrospective maximum-likelihood method for analysis of case-control studies. In this article, we develop an extension of the retrospective maximum-likelihood approach to studies where genetic information may be missing on some study subjects. In particular, special emphasis is given to haplotype-based studies where missing data arise due to linkage-phase ambiguity of genotype data. We use a profile likelihood technique and an appropriate expectation-maximization (EM) algorithm to derive a relatively simple procedure for parameter estimation, with or without a rare disease assumption, and possibly incorporating information on the marginal probability of the disease for the underlying population. We also describe two alternative robust approaches that are less sensitive to the underlying gene-environment independence and Hardy-Weinberg-equilibrium assumptions. The performance of the proposed methods is studied using simulation studies in the context of haplotype-based studies of gene-environment interactions. An application of the proposed method is illustrated using a case-control study of ovarian cancer designed to investigate the interaction between BRCA1/2 mutations and reproductive risk factors in the etiology of ovarian cancer.


Assuntos
Estudos de Casos e Controles , Exposição Ambiental , Predisposição Genética para Doença , Genótipo , Modelos Genéticos , Algoritmos , Alelos , Métodos Epidemiológicos , Feminino , Haplótipos , Humanos , Funções Verossimilhança , Modelos Logísticos , Neoplasias Ovarianas/genética , Projetos de Pesquisa , Fatores de Risco
14.
J Nutr ; 134(12): 3233-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15570018

RESUMO

We showed previously that the dietary combination of fish oil, rich in (n-3) fatty acids, and the fermentable fiber pectin enhances colonocyte apoptosis in a rat model of experimentally induced colon cancer. In this study, we propose that the mechanism by which this dietary combination heightens apoptosis is via modulation of the colonocyte redox environment. Male Sprague-Dawley rats (n = 60) were fed 1 of 2 fats (corn oil or fish oil) and 1 of 2 fibers (cellulose or pectin) for 2 wk before determination of reactive oxygen species (ROS), oxidative DNA damage, antioxidant enzyme activity [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx)] and apoptosis in isolated colonocytes. Fish oil enhanced ROS, whereas the combination of fish oil and pectin suppressed SOD and CAT and enhanced the SOD/CAT ratio compared with a corn oil and cellulose diet. Despite this modulation to a seemingly prooxidant environment, oxidative DNA damage was inversely related to ROS in the fish oil and pectin diet, and apoptosis was enhanced relative to other diets. Furthermore, apoptosis increased exponentially as ROS increased. These results suggest that the enhancement of apoptosis associated with fish oil and pectin feeding may be due to a modulation of the redox environment that promotes ROS-mediated apoptosis.


Assuntos
Antioxidantes/fisiologia , Apoptose/efeitos dos fármacos , Colo/citologia , Óleos de Peixe/farmacologia , Mucosa Intestinal/citologia , Pectinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Catalase/metabolismo , Colo/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Dieta , Óleos de Peixe/administração & dosagem , Mucosa Intestinal/efeitos dos fármacos , Masculino , Pectinas/administração & dosagem , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
15.
Carcinogenesis ; 23(11): 1919-25, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12419841

RESUMO

We have shown that a combination of fish oil (high in n-3 fatty acids) with the butyrate-producing fiber pectin, upregulates apoptosis in colon cells exposed to the carcinogen azoxymethane, protecting against colon tumor development. We now hypothesize that n-3 fatty acids prime the colonocytes such that butyrate can initiate apoptosis. To test this, 30 Sprague-Dawley rats were provided with diets differing in the fatty acid composition (corn oil, fish oil or a purified fatty acid ethyl ester diet). Intact colon crypts were exposed ex vivo to butyrate, and analyzed for reactive oxygen species (ROS), mitochondrial membrane potential (MMP), translocation of cytochrome C to the cytosol, and caspase-3 activity (early events in apoptosis). The fatty acid composition of the three major mitochondrial phospholipids was also determined, and an unsaturation index calculated. The unsaturation index in cardiolipin was correlated with ROS levels (R = 0.99; P = 0.02). When colon crypts from fish oil and FAEE-fed rats were exposed to butyrate, MMP decreased (P = 0.041); and translocation of cytochrome C to the cytosol (P = 0.037) and caspase-3 activation increased (P = 0.032). The data suggest that fish oil may prime the colonocytes for butyrate-induced apoptosis by enhancing the unsaturation of mitochondrial phospholipids, especially cardiolipin, resulting in an increase in ROS and initiating apoptotic cascade.


Assuntos
Apoptose/efeitos dos fármacos , Colo/citologia , Óleos de Peixe/farmacologia , Mucosa Intestinal/citologia , Membranas Intracelulares/efeitos dos fármacos , Lipídeos de Membrana/metabolismo , Mitocôndrias/efeitos dos fármacos , Fosfolipídeos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Butiratos/farmacologia , Cardiolipinas/química , Cardiolipinas/metabolismo , Caspase 3 , Caspases/metabolismo , Colo/metabolismo , Óleo de Milho/farmacologia , Grupo dos Citocromos c/metabolismo , Gorduras Insaturadas na Dieta/farmacologia , Ativação Enzimática , Ésteres/farmacologia , Ácidos Graxos/farmacologia , Mucosa Intestinal/metabolismo , Membranas Intracelulares/metabolismo , Peroxidação de Lipídeos , Masculino , Lipídeos de Membrana/química , Mitocôndrias/metabolismo , Estresse Oxidativo , Fosfolipídeos/química , Ratos , Ratos Sprague-Dawley
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