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1.
Pathology ; 54(1): 49-54, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34955242

RESUMO

Previous reports have shown that quantification of high tumour grade is of prognostic significance for patients with prostate cancer. In particular, percent Gleason pattern 4 (GP4) has been shown to predict outcome in several studies, although conflicting results have also been reported. A major issue with these studies is that they rely on surrogate markers of outcome rather than patient survival. We have investigated the prognostic predictive value of quantifying GP4 in a series of prostatic biopsies containing Gleason score 3+4=7 and 4+3=7 tumours. It was found that the length of GP4 tumour determined from the measurement of all biopsy cores from a single patient, percent GP4 present and absolute GP4 were all significantly associated with distant progression of tumour, all-cause mortality and cancer-specific mortality over a 10-year follow-up period. Assessment of the relative prognostic significance showed that these parameters outperformed division of cases according to Gleason score (3+4=7 versus 4+3=7). International Society of Urological Pathology (ISUP) Grade Groups currently divide these tumours, according to Gleason grading guidelines, into grade 2 (3+4=7) and grade 3 (4+3=7). Our results indicate that this simple classification results in the loss of important prognostic information. In view of this we would recommend that ISUP Grade Groups 2 and 3 be amalgamated as grade 2 tumour with the percentage of GP4 carcinoma being appended to the final grade, e.g., 3+4=7 carcinoma with 40% pattern 4 tumour would be classified as ISUP Grade Group 2 (40%).


Assuntos
Adenocarcinoma/patologia , Prognóstico , Neoplasias da Próstata/patologia , Biópsia com Agulha de Grande Calibre , Humanos , Masculino , Gradação de Tumores/métodos , Próstata/patologia , Prostatectomia , Estudos Retrospectivos
2.
Sci Rep ; 9(1): 13907, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31554862

RESUMO

Primary infection of legumes by rhizobia involves the controlled localized enzymatic breakdown of cell walls at root hair tips. Previous studies determined the role of rhizobial CelC2 cellulase in different steps of the symbiotic interaction Rhizobium leguminosarum-Trifolium repens. Recent findings also showed that CelC2 influences early signalling events in the Ensifer meliloti-Medicago truncatula interaction. Here, we have monitored the root hair phenotypes of two legume plants, T. repens and M. sativa, upon inoculation with strains of their cognate and non-cognate rhizobial species, R. leguminosarum bv trifolii and E. meliloti, (over)expressing the CelC2 coding gene, celC. Regardless of the host, CelC2 specifically elicited 'hole-on-the-tip' events (Hot phenotype) in the root hair apex, consistent with the role of this endoglucanase in eroding the noncrystalline cellulose found in polarly growing cell walls. Overproduction of CelC2 also increased root hair tip redirections (RaT phenotype) events in both cognate and non-cognate hosts. Interestingly, heterologous celC expression also induced non-canonical alterations in ROS (Reactive Oxygen Species) homeostasis at root hair tips of Trifolium and Medicago. These results suggest the concurrence of shared unspecific and host-related plant responses to CelC2 during early steps of symbiotic rhizobial infection. Our data thus identify CelC2 cellulase as an important determinant of events underlying early infection of the legume host by rhizobia.


Assuntos
Celulase/metabolismo , Fabaceae/metabolismo , Fabaceae/microbiologia , Interações Hospedeiro-Patógeno/fisiologia , Rhizobium leguminosarum/metabolismo , Simbiose/fisiologia , Parede Celular/metabolismo , Parede Celular/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Medicago truncatula/metabolismo , Medicago truncatula/microbiologia , Fenótipo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Nódulos Radiculares de Plantas/metabolismo , Nódulos Radiculares de Plantas/microbiologia , Trifolium/metabolismo , Trifolium/microbiologia
3.
Brain Res ; 1678: 330-336, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29103988

RESUMO

Cerebellar Abiotrophy (CA) is a neurodegenerative disease in Arabian horses affecting the cerebellum, more specifically the Purkinje neurons. Although CA occurs in several domestic species, CA in Arabian horses is unique in that a single nucleotide polymorphism (SNP) has been associated with the disease. Total RNA sequencing (RNA-seq) was performed on CA-affected horses to address the molecular mechanism underlying the disease. This research expands upon the RNA-seq work by measuring the impact of the CA-associated SNP on the candidate gene MutY homolog (MUTYH) and its regulation, isoform-specific expression and protein localization. We hypothesized that the CA-associated SNP compromises the promoter region of MUTYH, leading to differential expression of its isoforms. Our research demonstrates that the CA-associated SNP introduces a new binding site for a novel transcription factor (Myelin Transcription Factor-1 Like protein, MYT1L). In addition, CA-affected horses show differential expression of a specific isoform of MUTYH as well as different localization in the Purkinje and granular neurons of the cerebellum.


Assuntos
Doenças Cerebelares/genética , Doenças Cerebelares/veterinária , Cerebelo/patologia , DNA Glicosilases/genética , Polimorfismo de Nucleotídeo Único/genética , Animais , Doenças Cerebelares/patologia , Análise Mutacional de DNA , Transtornos Heredodegenerativos do Sistema Nervoso/genética , Transtornos Heredodegenerativos do Sistema Nervoso/veterinária , Cavalos/genética , Células de Purkinje/metabolismo , Células de Purkinje/patologia
4.
BMC Genomics ; 18(1): 511, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-28676104

RESUMO

BACKGROUND: Efforts to resolve the transcribed sequences in the equine genome have focused on protein-coding RNA. The transcription of the intergenic regions, although detected via total RNA sequencing (RNA-seq), has yet to be characterized in the horse. The most recent equine transcriptome based on RNA-seq from several tissues was a prime opportunity to obtain a concurrent long non-coding RNA (lncRNA) database. RESULTS: This lncRNA database has a breadth of eight tissues and a depth of over 20 million reads for select tissues, providing the deepest and most expansive equine lncRNA database. Utilizing the intergenic reads and three categories of novel genes from a previously published equine transcriptome pipeline, we better describe these groups by annotating the lncRNA candidates. These lncRNA candidates were filtered using an approach adapted from human lncRNA annotation, which removes transcripts based on size, expression, protein-coding capability and distance to the start or stop of annotated protein-coding transcripts. CONCLUSION: Our equine lncRNA database has 20,800 transcripts that demonstrate characteristics unique to lncRNA including low expression, low exon diversity and low levels of sequence conservation. These candidate lncRNA will serve as a baseline lncRNA annotation and begin to describe the RNA-seq reads assigned to the intergenic space in the horse.


Assuntos
Cavalos/metabolismo , RNA Longo não Codificante/genética , Transcriptoma , Animais , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Cavalos/genética , Especificidade de Órgãos , Análise de Sequência de RNA
5.
BMC Genomics ; 18(1): 103, 2017 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-28107812

RESUMO

BACKGROUND: Transcriptome interpretation relies on a good-quality reference transcriptome for accurate quantification of gene expression as well as functional analysis of genetic variants. The current annotation of the horse genome lacks the specificity and sensitivity necessary to assess gene expression especially at the isoform level, and suffers from insufficient annotation of untranslated regions (UTR) usage. We built an annotation pipeline for horse and used it to integrate 1.9 billion reads from multiple RNA-seq data sets into a new refined transcriptome. RESULTS: This equine transcriptome integrates eight different tissues from 59 individuals and improves gene structure and isoform resolution, while providing considerable tissue-specific information. We utilized four levels of transcript filtration in our pipeline, aimed at producing several transcriptome versions that are suitable for different downstream analyses. Our most refined transcriptome includes 36,876 genes and 76,125 isoforms, with 6474 candidate transcriptional loci novel to the equine transcriptome. CONCLUSIONS: We have employed a variety of descriptive statistics and figures that demonstrate the quality and content of the transcriptome. The equine transcriptomes that are provided by this pipeline show the best tissue-specific resolution of any equine transcriptome to date and are flexible for several downstream analyses. We encourage the integration of further equine transcriptomes with our annotation pipeline to continue and improve the equine transcriptome.


Assuntos
Perfilação da Expressão Gênica , Genoma , Genômica , Transcriptoma , Animais , Mapeamento Cromossômico , Análise por Conglomerados , Biologia Computacional/métodos , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Cavalos , Anotação de Sequência Molecular , Especificidade de Órgãos/genética , Isoformas de RNA
6.
Cerebellum ; 16(2): 462-472, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27709457

RESUMO

Equine cerebellar abiotrophy (CA) is a hereditary neurodegenerative disease that affects the Purkinje neurons of the cerebellum and causes ataxia in Arabian foals. Signs of CA are typically first recognized either at birth to any time up to 6 months of age. CA is inherited as an autosomal recessive trait and is associated with a single nucleotide polymorphism (SNP) on equine chromosome 2 (13074277G>A), located in the fourth exon of TOE1 and in proximity to MUTYH on the antisense strand. We hypothesize that unraveling the functional consequences of the CA SNP using RNA-seq will elucidate the molecular pathways underlying the CA phenotype. RNA-seq (100 bp PE strand-specific) was performed in cerebellar tissue from four CA-affected and five age-matched unaffected horses. Three pipelines for differential gene expression (DE) analysis were used (Tophat2/Cuffdiff2, Kallisto/EdgeR, and Kallisto/Sleuth) with 151 significant DE genes identified by all three pipelines in CA-affected horses. TOE1 (Log2(foldchange) = 0.92, p = 0.66) and MUTYH (Log2(foldchange) = 1.13, p = 0.66) were not differentially expressed. Among the major pathways that were differentially expressed, genes associated with calcium homeostasis and specifically expressed in Purkinje neurons, CALB1 (Log2(foldchange) = -1.7, p < 0.01) and CA8 (Log2(foldchange) = -0.97, p < 0.01), were significantly down-regulated, confirming loss of Purkinje neurons. There was also a significant up-regulation of markers for microglial phagocytosis, TYROBP (Log2(foldchange) = 1.99, p < 0.01) and TREM2 (Log2(foldchange) = 2.02, p < 0.01). These findings reaffirm a loss of Purkinje neurons in CA-affected horses along with a potential secondary loss of granular neurons and activation of microglial cells.


Assuntos
Cerebelo/metabolismo , Transtornos Heredodegenerativos do Sistema Nervoso/veterinária , Doenças dos Cavalos/genética , Transcriptoma , Animais , Cerebelo/crescimento & desenvolvimento , Análise por Conglomerados , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , Feminino , Expressão Gênica , Transtornos Heredodegenerativos do Sistema Nervoso/genética , Transtornos Heredodegenerativos do Sistema Nervoso/metabolismo , Doenças dos Cavalos/metabolismo , Cavalos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Aprendizado de Máquina não Supervisionado
8.
Transgenic Res ; 25(3): 329-43, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26820414

RESUMO

The recombinant production of therapeutic proteins for human diseases is currently the largest source of innovation in the pharmaceutical industry. The market growth has been the driving force on efforts for the development of new therapeutic proteins, in which transgenesis emerges as key component. The use of the transgenic animal platform offers attractive possibilities, residing on the low production costs allied to high productivity and quality of the recombinant proteins. Although many strategies have evolved over the past decades for the generation of transgenic founders, transgenesis in livestock animals generally faces some challenges, mainly due to random transgene integration and control over transgene copy number. But new developments in gene editing with CRISPR/Cas system promises to revolutionize the field for its simplicity and high efficiency. In addition, for the final approval of any given recombinant protein for animal or human use, the production and characterization of bioreactor founders and expression patterns and functionality of the proteins are technical part of the process, which also requires regulatory and administrative decisions, with a large emphasis on biosafety. The approval of two mammary gland-derived recombinant proteins for commercial and clinical use has boosted the interest for more efficient, safer and economic ways to generate transgenic founders to meet the increasing demand for biomedical proteins worldwide.


Assuntos
Animais Geneticamente Modificados/genética , Biofarmácia/tendências , Gado/genética , Proteínas Recombinantes/genética , Animais , Reatores Biológicos , Técnicas de Transferência de Genes/tendências , Humanos , Proteínas Recombinantes/biossíntese
9.
Pathology ; 47(6): 520-5, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26325671

RESUMO

In 2014 a consensus conference convened by the International Society of Urological Pathology (ISUP) adopted amendments to the criteria for Gleason grading and scoring (GS) for prostatic adenocarcinoma. The meeting defined a modified grading system based on 5 grading categories (grade 1, GS 3+3; grade 2, GS 3+4; grade 3, GS 4+3; grade 4, GS 8; grade 5, GS 9-10). In this study we have evaluated the prognostic significance of ISUP grading in 496 patients enrolled in the TROG 03.04 RADAR Trial. There were 19 grade 1, 118 grade 2, 193 grade 3, 88 grade 4 and 79 grade 5 tumours in the series, with follow-up for a minimum of 6.5 years. On follow-up 76 patients experienced distant progression of disease, 171 prostate specific antigen (PSA) progression and 39 prostate cancer deaths. In contrast to the 2005 modified Gleason system (MGS), the hazards of the distant and PSA progression endpoints, relative to grade 2, were significantly greater for grades 3, 4 and 5 of the 2014 ISUP grading scheme. Comparison of predictive ability utilising Harrell's concordance index, showed 2014 ISUP grading to significantly out-perform 2005 MGS grading for each of the three clinical endpoints.


Assuntos
Adenocarcinoma/patologia , Gradação de Tumores , Neoplasias da Próstata/patologia , Adenocarcinoma/mortalidade , Adenocarcinoma/terapia , Adulto , Idoso , Antagonistas de Androgênios/administração & dosagem , Antineoplásicos/administração & dosagem , Biópsia com Agulha de Grande Calibre , Quimiorradioterapia/métodos , Conferências de Consenso como Assunto , Difosfonatos/administração & dosagem , Humanos , Imidazóis/administração & dosagem , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores/métodos , Gradação de Tumores/normas , Patologia Cirúrgica/normas , Modelos de Riscos Proporcionais , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/terapia , Sociedades Médicas , Urologia/normas , Ácido Zoledrônico
10.
Reprod Domest Anim ; 49(4): 648-656, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24943879

RESUMO

The presence of the zona pellucida has been perceived as a requirement for the oviductal transfer of cloned embryos at early stages of development while protecting the embryo from an immune system response. We hypothesized that steroid hormone therapy could reduce a potential cellular immune response after the transfer of zona-free cloned embryos into the oviduct of recipient female goats. In Experiment 1, seven does were used to study the systemic immunosuppressant effect of the methylprednisolone administration (for 3 days) on blood cell counts. Whole blood was collected prior to treatment with methyprednisolone and then on Days 1, 2, 3, 4, 7, 14, 21 and 28 after the first dose of methylprednisolone for the analysis of haematological parameters. Methylprednisolone treatment significantly reduced circulating white blood cells and neutrophils in comparison with pre-treatment levels, demonstrating a systemic immunosuppressant effect. In Experiment 2, a group of 58 does were used as recipient females to study the effect of administration of methylprednisolone for 3 days on the establishment of pregnancies after the transfer of zona-free cloned embryos into the oviducts. No effects on pregnancy rates on Day 30 were observed regarding the distinct treatment groups (control vs. methylprednisolone), the source of oocytes (in vivo- vs in vitro-matured) or the presence or absence of the zona pellucida in embryos. In summary, methylprednisolone was effective at inducing a systemic immunosuppressed state in goats, but the treatment prior to embryo transfer did not affect pregnancy rates. Moreover, pregnancy rates were similar between zona-free and zona-intact goat cloned embryos.


Assuntos
Clonagem de Organismos/veterinária , Transferência Embrionária/veterinária , Cabras , Terapia de Imunossupressão/veterinária , Metilprednisolona/administração & dosagem , Animais , Transferência Embrionária/métodos , Feminino , Terapia de Imunossupressão/métodos , Contagem de Leucócitos/veterinária , Neutrófilos , Técnicas de Transferência Nuclear/veterinária , Gravidez , Taxa de Gravidez , Zona Pelúcida/imunologia
11.
J Dairy Sci ; 95(12): 7200-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23040022

RESUMO

Coagulase-negative staphylococci (CNS) are the most commonly isolated bacteria from goat milk, but they have often been identified with phenotypic methods, which may have resulted in misclassification. The aims of this paper were to assess the amount of misclassification of a phenotypic test for identifying CNS species from goat milk compared with transfer RNA intergenic spacer PCR (tDNA-PCR) followed by capillary electrophoresis, and to apply the tDNA-PCR technique on different capillary electrophoresis equipment. Milk samples were collected from 416 does in 5 Californian dairy goat herds on 3 occasions during lactation. In total, 219 CNS isolates were identified at the species level with tDNA-PCR and subjected to the API 20 Staph identification test kit (API Staph; bioMérieux, Durham, NC). If the same species was isolated multiple times from the same udder gland, only the first isolate was used for further analyses, resulting in 115 unique CNS isolates. According to the tDNA-PCR test, the most prevalent CNS species were Staphylococcus epidermidis, Staphylococcus caprae, and Staphylococcus simulans. Typeability with API staph was low (72%). Although the API Staph test was capable of identifying the majority of Staph. epidermidis and Staph. caprae isolates, sensitivity for identification of Staph. simulans was low. The true positive fraction was high for the 3 most prevalent species. It was concluded that the overall performance of API Staph in differentiating CNS species from goat milk was moderate to low, mainly because of the low typeability, and that genotypic methods such as tDNA-PCR are preferred.


Assuntos
Leite/microbiologia , Staphylococcus/genética , Animais , Eletroforese Capilar/métodos , Eletroforese Capilar/veterinária , Feminino , Cabras/microbiologia , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/veterinária , RNA Bacteriano/genética , RNA de Transferência/genética , Staphylococcus/classificação , Staphylococcus epidermidis/genética
12.
J Biol Dyn ; 6 Suppl 2: 118-27, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22882019

RESUMO

A practical mathematical model for glioblastomas (brain tumours), which incorporates the two key parameters of tumour growth, namely the cancer cell diffusion and the cell proliferation rate, has been shown to be clinically useful and predictive. Previous studies explain why multifocal recurrence is inevitable and show how various treatment scenarios have been incorporated in the model. In most tumours, it is not known when the cancer started. Based on patient in vivo parameters, obtained from two brain scans, it is shown how to estimate the time, after initial detection, when the tumour started. This is an input of potential importance in any future controlled clinical study of any connection between cell phone radiation and brain tumour incidence. It is also used to estimate more accurately survival times from detection. Finally, based on patient parameters, the solution of the model equation of the tumour growth helps to explain why certain patients live longer than others after similar treatment protocols specifically surgical resection (removal) and irradiation.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Transformação Celular Neoplásica/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Simulação por Computador , Humanos , Análise de Sobrevida , Fatores de Tempo
13.
Interface Focus ; 2(4): 397-406, 2012 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-23919124

RESUMO

The application of mathematical models in biology and medicine has a long history. From the sparse number of papers in the first half of the twentieth century with a few scientists working in the field it has become vast with thousands of active researchers. We give a brief, and far from definitive history, of how some parts of the field have developed and how the type of research has changed. We describe in more detail just two examples of specific models which are directly related to real biological problems, namely animal coat patterns and the growth and image enhancement of glioblastoma brain tumours.

14.
Lipids ; 46(6): 495-504, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21442273

RESUMO

In a transgenic growth hormone (GH) mouse model, highly elevated GH increases overall growth and decreases adipose depots while low or moderate circulating GH enhances adipose deposition with differential effects on body growth. Using this model, the effects of low, moderate, and high chronic GH on fatty acid composition were determined for adipose and hepatic tissue and the metabolites of 20:4n-6 (arachidonic acid) were characterized to identify metabolic targets of action of elevated GH. The products of Δ-9 desaturase in hepatic, but not adipose, tissue were reduced in response to elevated GH. Proportional to the level of circulating GH, the products of Δ-5 and Δ-6 were increased in both adipose and hepatic tissue for the omega-6 lipids (e.g., 20:4n-6), while only the hepatic tissues showed an increase for omega-3 lipids (e.g., 22:6n-3). The eicosanoids, PGE2 and 12-HETE, were elevated with high GH but circulating thromboxane was not. Hepatic PTGS1 and 2 (COX1 and COX 2), SOD1, and FADS2 (Δ-6 desaturase) mRNAs were increased with elevated GH while FAS mRNA was reduced; SCD1 (stearoyl-coenzyme A desaturase) and SCD2 mRNA did not significantly differ. The present study showed that GH influences the net flux through various aspects of lipid metabolism and especially the desaturase metabolic processes. The combination of altered metabolism and tissue specificity suggest that the regulation of membrane composition and its effects on signaling pathways, including the production and actions of eicosanoids, can be mediated by the GH regulatory axis.


Assuntos
Ácido Araquidônico/metabolismo , Hormônio do Crescimento/metabolismo , Animais , Feminino , Hormônio do Crescimento/genética , Hormônio do Crescimento/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
15.
J Anim Sci ; 88(7): 2530-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20228236

RESUMO

Indirect modification of animal genomes by interspecific hybridization, cross-breeding, and selection has produced an enormous spectrum of phenotypic diversity over more than 10,000 yr of animal domestication. Using these established technologies, the farming community has successfully increased the yield and efficiency of production in most agricultural species while utilizing land resources that are often unsuitable for other agricultural purposes. Moving forward, animal well-being and agricultural sustainability are moral and economic priorities of consumers and producers alike. Therefore, these considerations will be included in any strategy designed to meet the challenges produced by global climate change and an expanding world population. Improvements in the efficiency and precision of genetic technologies will enable a timely response to meet the multifaceted food requirements of a rapidly increasing world population.


Assuntos
Criação de Animais Domésticos/métodos , Animais Domésticos/genética , Técnicas Genéticas/veterinária , Bem-Estar do Animal , Animais , Animais Geneticamente Modificados/genética , Alimentos/normas , Microbiologia de Alimentos/normas , Abastecimento de Alimentos , Engenharia Genética/veterinária , Humanos , Estado Nutricional
16.
J Anim Sci ; 88(4): 1588-91, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20154173

RESUMO

The application of genetic engineering to food animals is often viewed as a means to further increase animal productivity without regard for the welfare of the resulting animals. We offer the perspective that, on the contrary, genetic engineering can, and is, being used to improve animal welfare in modern production systems. Several examples are cited from the current work in the field of animal genetic engineering that should be included in the debate over whether genetically engineered animals should be used in production agriculture. The current debate has slowed the advancement of this technology, which could play a key role in improving animal welfare and sustainability, without considering the potential benefits.


Assuntos
Agricultura , Bem-Estar do Animal , Animais Domésticos , Animais Geneticamente Modificados , Agricultura/ética , Bem-Estar do Animal/ética , Animais , Bovinos , Galinhas , Engenharia Genética , Suínos
17.
J Dairy Sci ; 89(2): 518-24, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16428620

RESUMO

The potential for applying biotechnology to benefit animal agriculture and food production has long been speculated. The addition of human milk components with intrinsic antimicrobial activity and positive charge to livestock milk by genetic engineering has the potential to benefit animal health, as well as food safety and production. We generated one line of transgenic goats as a model for the dairy cow designed to express human lysozyme in the mammary gland. Here we report the characterization of the milk from 5 transgenic females of this line expressing human lysozyme in their milk at 270 microg/mL or 68% of the level found in human milk. Milk from transgenic animals had a lower somatic cell count, but the overall component composition of the milk and milk production were not different from controls. Milk from transgenic animals had a shorter rennet clotting time and increased curd strength. Milk of such nature may be of benefit to the producer by influencing udder health and milk processing.


Assuntos
Animais Geneticamente Modificados/genética , Cabras/genética , Lactação , Glândulas Mamárias Animais/enzimologia , Leite/química , Muramidase/genética , Animais , Animais Geneticamente Modificados/fisiologia , Anti-Infecciosos , Contagem de Células , Quimosina/metabolismo , Feminino , Manipulação de Alimentos/métodos , Expressão Gênica , Cabras/fisiologia , Humanos , Leite/citologia
18.
Transgenic Res ; 14(4): 441-8, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16201410

RESUMO

Most studies utilizing transgenic technology focus on the impact to traits of interest, rather than propagation of the transgene to offspring. In animals containing growth hormone constructs, transgene transmission to progeny follows a Mendelian pattern of inheritance in the first few generations following generation of a founder animal, but decreases in subsequent generations. In the present study, the ovine metallothionein 1a-ovine growth hormone (oMt1a-oGH) transgenic mouse was used to determine whether transgene transmission rate to progeny was affected by overexpression of ovine growth hormone in the transgenic parent. The oMt1a-oGH mouse is a useful model for assessing transgene transmission, as the construct is easily regulatable and transgene inactivation results in a return of plasma GH to basal levels. Male and female hemizygous oMt1a-oGH mice were assigned to 1 of 3 treatment groups: (1) mice never actively expressing the transgene, (2) mice actively expressing the transgene from 3 weeks of age, and (3) mice actively expressing the transgene from 3 to 11 (males) or 3 to 8 (females) weeks of age. Transgenic mice were mated to wild type animals and the resulting progeny were genotyped. Males never actively expressing the transgene passed on the transgene to progeny in a Mendelian fashion, while males actively expressing the transgene transmitted the transgene to a smaller than expected number of progeny. However, following inactivation of the oMt1a-oGH construct in transgenic males, subsequent offspring demonstrated Mendelian inheritance of the transgene. In contrast, females expressing the transgene from 3 to 8 weeks of age were able to pass on the oMt1a-oGH construct in a Mendelian fashion, but females from other treatment groups were not. In oMt1a-oGH males, reduced transgene transmission appears to be due to selection against transgenic gametes. In females, however, selection against the transgenic genotype likely occurs at the embryonic level.


Assuntos
Hormônio do Crescimento/genética , Metalotioneína/genética , Camundongos Transgênicos/genética , Camundongos/genética , Transgenes/fisiologia , Animais , Feminino , Genótipo , Masculino , Camundongos Endogâmicos CBA , Gravidez , Transgenes/genética
20.
J Dairy Sci ; 87(10): 3510-4, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15377629

RESUMO

Stearoyl-CoA desaturase enzyme converts specific medium- and long-chain saturated fatty acids to their monounsaturated form. Transgenic goats expressing a bovine beta-lactoglobulin promoter-rat stearoyl-CoA desaturase cDNA construct in mammary gland epithelial cells were produced by pronuclear microinjection. The fatty acid composition of milk from 4 female transgenic founders was analyzed on d 7, 14, and 30 of their first lactation. In 2 animals, the expression of the transgene changed the overall fatty acid composition of the resulting milk fat to a less saturated and more monounsaturated fatty acid profile at d 7 of lactation; however, this effect diminished by d 30. In addition, one animal had an increased proportion of the rumen-derived monounsaturated fatty acid C18:1 trans11 converted by stearoyl-CoA desaturase to the conjugated linoleic acid isomer C18:2 cis9 trans11. Milk that has higher proportions of monounsaturated fatty acids and conjugated linoleic acid may have benefits for human cardiovascular health.


Assuntos
Animais Geneticamente Modificados , Ácidos Graxos/análise , Cabras/genética , Leite/química , Estearoil-CoA Dessaturase/genética , Animais , Bovinos , DNA Complementar/genética , Células Epiteliais/enzimologia , Ácidos Graxos Monoinsaturados/análise , Feminino , Expressão Gênica , Lactação , Lactoglobulinas/genética , Ácidos Linoleicos Conjugados/análise , Glândulas Mamárias Animais/enzimologia , Regiões Promotoras Genéticas/genética , Ratos , Estearoil-CoA Dessaturase/metabolismo
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