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1.
Aust Vet J ; 102(6): 285-292, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38342502

RESUMO

INTRODUCTION: Reducing antibiotic use in production animal systems is one strategy which may help to limit the development of antimicrobial resistance. To reduce antimicrobial use in food-producing animals, it is important to first understand how antibiotics are used on farm and what barriers exist to decreasing their use. In dairy production systems, mastitis is one of the most common reasons for administering antimicrobials. Therefore, it is important to understand the motivations and behaviours of dairy farmers in relation to the diagnosis, treatment and prevention of mastitis. MATERIALS AND METHODS: In this study, we interviewed a sample of dairy farmers and dairy industry professionals from the major dairying regions of eastern Australia regarding their current practices used to diagnose, treat, and control subclinical and clinical mastitis. Inductive thematic analysis was used to code interview transcripts and identify the recurrent themes. RESULTS: Four overarching themes were identified: (1) the challenges associated with the detection and diagnosis of clinical mastitis, including with laboratory culture, (2) the motivations behind treatment decisions for different cases, (3) decisions around dry cow therapy and the role of herd recording, and (4) concerns regarding the development of antimicrobial resistance. DISCUSSION: This study identifies several challenges which may limit the ability of Australian dairy farmers to reduce antimicrobial use on farm, such as the need for rapid and reliable diagnostic tests capable of identifying the pathogenic causes of mastitis and the difficulties associated with conducting herd recording for the implementation of selective dry cow therapy. Industry professionals were concerned that farmers were not using individual cow records to aid in treatment decisions, which could result in unnecessary antimicrobial use. The results of this study can act as the basis for future research aimed at assessing these issues across the broader Australian dairy industry.


Assuntos
Indústria de Laticínios , Fazendeiros , Mastite Bovina , Animais , Bovinos , Indústria de Laticínios/métodos , Feminino , Austrália , Mastite Bovina/prevenção & controle , Mastite Bovina/tratamento farmacológico , Fazendeiros/psicologia , Antibacterianos/uso terapêutico , Humanos
2.
Poult Sci ; 101(3): 101648, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35093770

RESUMO

Biobanked poultry ovaries can be revived via transplantation into a recipient female, which upon maturity will produce donor-derived progeny. Previously, a large portion of these recipients also produced recipient-derived progeny, making them gonadal chimeras. These were potentially created when portions of the recipient's ovary were inadvertently left behind. Completely removing the recipient ovary would solve this problem; however, leaving a portion of the recipient's ovary may have inadvertently increased the transplant attachment rate by providing a damaged area for attachment. To test this hypothesis in the turkey, we removed various portions (33-100%) of recipient ovarian tissue and determined the transplant attachment rate. Furthermore, the use of the abdominal air sac membrane as an additional anchoring point was tested. The overall attachment rate of transplants was 91% (27/30), while the average size of the transplants was 4.2 ± 0.6 mm2, 6 d postsurgery. There was no difference (P > 0.05) in the attachment rates, or transplant size between groups with varying amounts of recipent tissue removed, or by using the abdominal air sac membrane as an anchor. Finally, the immunological status of the grafts were evaluated by analyzing the presences of CD3 and MUM-1 (T and B cell markers). This showed that all transplants were infiltrated by large numbers of T and B cells. Shown by a high (P ≤ 0.001) percentage of CD3-positive immunostained cytoplasmic area (49.78 ± 3.90%) in transplants compared to remnant recipient tissue (0.30 ± 0.10%), as well as a high (P ≤ 0.001) percentage of MUM-1-positive immunostained nuclear area (9.85 ± 1.95%) in transplants over remnant recipient tissues (0.39 ± 0.12%). From this study we would recommend removing the entire recipient ovary, and not covering the transplants with the abdominal air sac membrane, to prevent gonadal chimeras. The high levels of lymphocytes within the grafts indicate possible tissue rejection, which could be overcome via immunosuppression with or without histocompatibility matching between donors and recipients.


Assuntos
Galinhas , Ovário , Animais , Feminino , Humanos , Terapia de Imunossupressão/veterinária , Doadores de Tecidos
3.
Poult Sci ; 101(2): 101601, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34954445

RESUMO

Pendulous crop (PC) in the turkey occurs when the crop distends from its normal position, thereby preventing the movement of feed and water from the crop down into the digestive system. This condition negatively impacts the turkey industry at both production and welfare levels. In this study, we estimated the genetic parameters for PC incidence and its genetic correlation with 5 production traits. Additionally, we evaluated the prediction accuracy and bias of breeding values for the selection candidates using pedigree (BLUP) or pedigree-genomic (ssGBLUP) relationships among the animals. A total of 245,783 turkey records were made available by Hybrid Turkeys, Kitchener, Canada. Of these, 6,545 were affected with PC. In addition, the data included 9,634 records for breast meat yield (BMY); 5,592 records for feed conversion ratio (FCR) and residual feed intake (RFI) in males; 170,844 records for body weight (BW) and walking score (WS) between 18 and 20 wk of age for males (71,012) and females (99,832), respectively. Among this population, 36,830 were genotyped using a 65K SNP Illumina Inc. chip. While all animals passed the quality control criteria, only 53,455 SNP markers were retained for subsequent analysis. Heritability for PC was estimated at 0.16 ± 0.00 and 0.17 ± 0.00 using BLUP and ssGBLUP, respectively. The incidence of PC was not genetically correlated with WS or FCR. Low unfavourable genetic correlations with BW (0.12 and 0.14), BMY (0.24 and 0.24) and RFI (-0.33 and -0.28) were obtained using BLUP and ssGBLUP, respectively. Using ssGBLUP showed higher prediction accuracy (0.51) for the breeding values for the selection candidates than the pedigree-based model (0.35). Whereas the bias of the prediction was slightly reduced with ssGBLUP (0.33 ± 0.05) than BLUP (0.30 ± 0.08), both models showed a regression coefficient lower than one, indicating inflation in the predictions. The results of this study suggest that PC is a heritable trait and selection for lower PC incidence rates is feasible. Although further investigation is necessary, selection for BW, BMY, and RFI may increase PC incidence. Incorporating genomic information would lead to higher accuracy in predicting the genetic merit for selection candidates.


Assuntos
Modelos Genéticos , Perus , Animais , Peso Corporal , Galinhas , Feminino , Genômica , Genótipo , Masculino , Linhagem , Fenótipo , Perus/genética
4.
Poult Sci ; 99(12): 7109-7121, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33248628

RESUMO

Biobanking of turkey ovarian tissue appears to be the most cost-effective method for the long-term preservation of female genetics. However, to ensure the successful transplantation of biobanked ovarian tissue for breed or line revival, the transplantation and development of fresh ovarian tissue must be evaluated. To assess transplantability, ovaries from poults 1 to 15 days posthatch (dph) were cultured in ovo in chicken eggs for 6 d and compared with the equivalent fresh tissue. The viability of cultured ovarian tissue was evaluated visually, whereas the level of late-stage apoptosis was measured via the TUNEL assay. In addition, the diameter and density of prefollicular germ cells and follicles (primordial and primary) were measured to assess maturation. Results showed that all cultured grafts (74/74), on surviving chicken chorioallantoic membrane, were viable with low levels (0.8 ± 0.1%) of late-stage apoptosis. The diameter of prefollicular germ cells in cultured ovaries from poults at 5 and 7 dph were larger (P < 0.002) than that of their preculture counterparts but were not able to reach their in vivo size. No significant follicular growth was observed in ovaries cultured in ovo; however, prefollicular germ cell density was over 4-fold greater in ovaries cultured from 7 dph poults (81,030 ± 17,611/mm3) than in their in vivo counterpart (16,463 ± 6,805/mm3). Interestingly, cultured ovaries from all other ages displayed equal or lower (P ≤ 0.05) prefollicular germ cell densities than their in vivo counterparts. Cultured ovaries from poults at 5 and 7 dph also exhibited an increase (P ≤ 0.05) in follicle density compared with their preculture counterparts; whereas, cultured ovaries from 15 dph poults had decreased densities (P < 0.001) compared with their preculture counterparts. This study demonstrated that, although age of ovarian tissue cultured in ovo did not affect the overall viability, 7 dph ovaries appeared to have a better cellular morphology after culturing in ovo than other ages. In addition, we also demonstrated for the first time that avian follicles can form during tissue culturing in ovo.


Assuntos
Bancos de Espécimes Biológicos , Ovário , Óvulo , Tolerância ao Transplante , Perus , Animais , Galinhas , Feminino , Folículo Ovariano/crescimento & desenvolvimento , Ovário/transplante , Óvulo/citologia , Óvulo/metabolismo , Tolerância ao Transplante/fisiologia , Transplantes/normas
5.
Anim Genet ; 51(6): 876-889, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33006154

RESUMO

Deviation from Mendelian inheritance expectations (transmission ratio distortion, TRD) has been observed in several species, including the mouse and humans. In this study, TRD was characterized in the turkey genome using both allelic (specific- and unspecific-parent TRD) and genotypic (additive- and dominance-TRD) parameterizations within a Bayesian framework. In this study, we evaluated TRD for 23 243 genotyped Turkeys across 56 393 autosomal SNPs. The analyses included 500 sires, 2013 dams and 11 047 offspring (trios). Three different haplotype sliding windows of 4, 10 and 20 SNPs were used across the autosomal chromosomes. Based on the genotypic parameterizations, 14 haplotypes showed additive and dominance TRD effects highlighting regions with a recessive TRD pattern. In contrast, the allelic model uncovered 12 haplotype alleles with the allelic TRD pattern which showed an underrepresentation of heterozygous offspring in addition to the absence of homozygous animals. For regions with the allelic pattern, only one particular region showed a parent-specific TRD where the penetrance was high via the dam, but low via the sire. The gene set analysis uncovered several gene ontology functional terms, Reactome pathways and several Medical Subject Headings that showed significant enrichment of genes associated with TRD. Many of these gene ontology functional terms (e.g. mitotic spindle assembly checkpoint, DRM complex and Aneuploidy), Reactome pathways (e.g. Mismatch repair) and Medical Subject Headings (e.g. Adenosine monophosphate) are known to be related to fertility, embryo development and lethality. The results of this study revealed potential novel candidate lethal haplotypes, functional terms and pathways that may enhance breeding programs in Turkeys through reducing mortality and improving reproduction rate.


Assuntos
Genes Letais , Modelos Genéticos , Perus/genética , Alelos , Animais , Teorema de Bayes , Cruzamento , Feminino , Genótipo , Haplótipos , Heterozigoto , Padrões de Herança , Masculino , Polimorfismo de Nucleotídeo Único
6.
Poult Sci ; 99(5): 2746-2756, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359612

RESUMO

This study determined, for the first time, the different subpopulations of germ cells and stereological changes within the cortex of the functional left ovary during germ cell nest breakdown, and formation of the primordial follicle pool in the domestic turkey. This was accomplished by measuring the size, density, and count of prefollicular germ cells and primordial follicles in turkey poults between 1 and 35 days posthatch (dph). The percent volume (PV) of germ cells and follicles within the cortex was also calculated as a means of validating the counting technique. The total percent volume of germ cells and primordial follicles within the cortex ranged between 42 and 84%, suggesting that the counting technique was valid. Our findings show that before germ cell nest breakdown (5 dph), there were roughly 1,000,000 prefollicular germ cells within the cortex of the left ovary and that germ cell nest breakdown initiated between 5 and 7 dph, characterized by a decrease (P ≤ 0.001) in prefollicular germ cell density and the subsequent appearance of primordial follicles. Nest breakdown is followed on day 9 by the first increase (P ≤ 0.05) in size of prefollicular germ cells. These cells continue to grow throughout nest breakdown. The majority (>90%) of germ cell nest breakdowns concluded by 15 dph; although, the primordial follicle pool was not fully established until 35 dph, as determined by a total lack of prefollicular germ cells. At this point, the pool was comprised of an estimated 60,000 primordial follicles and shows that during nest breakdown and follicle pool formation, ∼94% of germ cells were lost. This 94% decrease in the number of germ cells during nest breakdown in the turkey is comparable to the domestic chicken but is greater than the average two-thirds which are lost in mammalian species.


Assuntos
Células Germinativas/fisiologia , Folículo Ovariano/fisiologia , Perus/fisiologia , Animais , Feminino
7.
Poult Sci ; 98(12): 6263-6269, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31407014

RESUMO

The objective of this study was to estimate phenotypic and genetic parameters for clutch and broodiness (BR) traits in turkeys and their relationship with body weight and egg production. Data on dam line hens was available and included: body weight at 18 wk of age (BW18), body weight at lighting (BWL, 29 to 33 wk), age at first egg (AFE), egg number (EN), rate of lay (RL), clutch length (CL), maximum clutch length (MCL), pause length (PL), maximum PL (MPL) and BR. BR was defined as the average number of consecutive pause days between clutches that was higher than the average PL per hen. Heritability estimates for BW18 and BWL were 0.50 and 0.53, respectively. The heritability for egg production, clutch, and pause traits varied from low (MPL = 0.15; BR = 0.15) to moderate (AFE = 0.22; EN = 0.28; RL = 0.29; CL = 0.21; MCL = 0.27; PL = 0.25). Genetic correlations were negative between body weight traits and EN (rg (BW18, EN) = -0.27; rg(BWL, EN) = -0.33) and CL (rg(BW18, CL) = -0.40; rg(BWL, CL) = -0.33). BR was negatively genetically correlated with EN (rg(BR, EN) = -0.85) and CL (rg(BR, CL) = -0.30), and positively genetically correlated with PL (rg(BR, PL) = 0.93) and AFE (rg(BR, AFE) = 0.21). EN had a positive (0.73) and a negative (-0.84) genetic correlation with CL and PL, respectively. Overall, the results of this study confirmed the negative (unfavorable) correlations between egg production and body weight. Despite unfavorable genetic and phenotypic correlations between egg production traits and those relating to BR, the inclusion of BR in a selection program through incorporation of clutch length traits and pause length traits is feasible. Integration of either clutch length traits or pause length traits in a selection index is likely to increase egg number while decreasing broodiness.


Assuntos
Peso Corporal/genética , Tamanho da Ninhada/genética , Comportamento de Nidação , Reprodução/genética , Perus/fisiologia , Animais , Feminino , Perus/genética
8.
J Digit Imaging ; 32(4): 597-604, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31044392

RESUMO

Deep learning with convolutional neural networks (CNNs) has experienced tremendous growth in multiple healthcare applications and has been shown to have high accuracy in semantic segmentation of medical (e.g., radiology and pathology) images. However, a key barrier in the required training of CNNs is obtaining large-scale and precisely annotated imaging data. We sought to address the lack of annotated data with eye tracking technology. As a proof of principle, our hypothesis was that segmentation masks generated with the help of eye tracking (ET) would be very similar to those rendered by hand annotation (HA). Additionally, our goal was to show that a CNN trained on ET masks would be equivalent to one trained on HA masks, the latter being the current standard approach. Step 1: Screen captures of 19 publicly available radiologic images of assorted structures within various modalities were analyzed. ET and HA masks for all regions of interest (ROIs) were generated from these image datasets. Step 2: Utilizing a similar approach, ET and HA masks for 356 publicly available T1-weighted postcontrast meningioma images were generated. Three hundred six of these image + mask pairs were used to train a CNN with U-net-based architecture. The remaining 50 images were used as the independent test set. Step 1: ET and HA masks for the nonneurological images had an average Dice similarity coefficient (DSC) of 0.86 between each other. Step 2: Meningioma ET and HA masks had an average DSC of 0.85 between each other. After separate training using both approaches, the ET approach performed virtually identically to HA on the test set of 50 images. The former had an area under the curve (AUC) of 0.88, while the latter had AUC of 0.87. ET and HA predictions had trimmed mean DSCs compared to the original HA maps of 0.73 and 0.74, respectively. These trimmed DSCs between ET and HA were found to be statistically equivalent with a p value of 0.015. We have demonstrated that ET can create segmentation masks suitable for deep learning semantic segmentation. Future work will integrate ET to produce masks in a faster, more natural manner that distracts less from typical radiology clinical workflow.


Assuntos
Aprendizado Profundo , Movimentos Oculares/fisiologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/diagnóstico por imagem , Redes Neurais de Computação , Humanos , Meninges/diagnóstico por imagem
9.
Prostate Cancer Prostatic Dis ; 20(3): 348-351, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28440325

RESUMO

BACKGROUND: Analysis of systematic 12-core biopsies (SBx) has shown that African-American (AA) men tend to harbor higher risk prostate cancer (PCa) at presentation relative to other races. Multiparametric magnetic resonance imaging (mpMRI) and MRI-ultrasound fusion-guided biopsy (FBx) have been shown to diagnose more intermediate- and high-risk PCa in the general population; however, the efficacy in AA remains largely uncharacterized. We aim to evaluate the utility of FBx in an AA patient cohort. METHODS: Men suspected of PCa underwent an mpMRI and FBx with concurrent SBx from 2007 to 2015 in this institutional review board-approved prospective cohort study. Patient demographics, imaging and fusion biopsy variables were collected. χ2, Mann-Whitney U-test and McNemar's tests were performed to compare proportions, means and paired variables, respectively. Clinically significant PCa (CSPCa) was defined as Gleason score ⩾3+4. RESULTS: Fusion biopsy demonstrated exact agreement with SBx risk categories in 64% of AA men. There was no statistically significant difference in the detection of CSPCa between FBx vs SBx (68 vs 62 cases, P=0.36). However, FBx detected 41% fewer cases of clinically insignificant PCa (CIPCa) compared with SBx (FBx 30 vs SBx 51 cases, P=0.0004). The combined FBx/SBx biopsy approach detected significantly more cases of CSPCa (FBx/SBx 80 vs SBx 62 cases, P=0.004) while detecting comparable number of cases of CIPCa (FBx/SBx 45 vs SBx 51 cases, P=0.37) compared with SBx alone. FBx/SBx also detected more CSPCa in patients with a history of prior negative SBx (FBx/SBx 28 vs 19 cases, P=0.003). CONCLUSIONS: FBx when used in combination with SBx detected more cases of CSPCa while not significantly increasing the diagnosis of CIPCa in AA men. Future multicenter studies will be needed to validate ultimately the clinical implications of FBx in AA patients.


Assuntos
Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Negro ou Afro-Americano , Idoso , Erros de Diagnóstico , Humanos , Biópsia Guiada por Imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Próstata/diagnóstico por imagem , Ultrassonografia
10.
Prostate Cancer Prostatic Dis ; 20(2): 179-185, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28220802

RESUMO

BACKGROUND: The Prostate Cancer Prevention Trial Risk Calculator 2.0 (PCPTRC) is a widely used risk-based calculator used to assess a man's risk of prostate cancer (PCa) before biopsy. This risk calculator was created from data of a patient cohort undergoing a 6-core sextant biopsy, and subsequently validated in men undergoing 12-core systematic biopsy (SBx). The accuracy of the PCPTRC has not been studied in patients undergoing magnetic resonance imaging/ultrasound (MRI/US) fusion-guided biopsy (FBx). We sought to assess the performance of the PCPTRC for straitifying PCa risk in a FBx cohort. METHODS: A review of a prospective cohort undergoing MRI and FBx/SBx was conducted. Data from consecutive FBx/SBx were collected between August 2007 and February 2014, and PCPTRC scores using the PCPTRC2.0R-code were calculated. The risk of positive biopsy and high-grade cancer (Gleason ⩾7) on biopsy was calculated and compared with overall and high-grade cancer detection rates (CDRs). Receiver operating characteristic curves were generated and the areas under the curves (AUCs) were compared using DeLong's test. RESULTS: Of 595 men included in the study, PCa was detected in 39% (232) by SBx compared with 48% (287) on combined FBx/SBx biopsy. The PCPTRC AUCs for the CDR were similar (P=0.70) for SBx (0.69) and combined biopsy (0.70). For high-grade disease, AUCs for SBx (0.71) and combined biopsy (0.70) were slightly higher, but were not statistically different (P=0.55). CONCLUSIONS: In an MRI-screened population of men undergoing FBx, PCPTRC continues to represent a practical method of accurately stratifying PCa risk.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Biópsia Guiada por Imagem/métodos , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico , Idoso , Detecção Precoce de Câncer , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Medição de Risco
11.
Int J Cancer ; 139(7): 1648-57, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27194579

RESUMO

The eukaryotic translation initiation factor 4E (eIF4E) is a potent oncogene that is found to be dysregulated in 30% of human cancer, including colorectal carcinogenesis (CRC). ISIS 183750 is a second-generation antisense oligonucleotide (ASO) designed to inhibit the production of the eIF4E protein. In preclinical studies we found that EIF4e ASOs reduced expression of EIF4e mRNA and inhibited proliferation of colorectal carcinoma cells. An additive antiproliferative effect was observed in combination with irinotecan. We then performed a clinical trial evaluating this combination in patients with refractory cancer. No dose-limiting toxicities were seen but based on pharmacokinetic data and tolerability the dose of irinotecan was reduced to 160 mg/m(2) biweekly. Efficacy was evaluated in 15 patients with irinotecan-refractory colorectal cancer. The median time of disease control was 22.1 weeks. After ISIS 183750 treatment, peripheral blood levels of eIF4E mRNA were decreased in 13 of 19 patients. Matched pre- and posttreatment tumor biopsies showed decreased eIF4E mRNA levels in five of nine patients. In tumor tissue, the intracellular and stromal presence of ISIS 183750 was detected by IHC in all biopsied patients. Although there were no objective responses stable disease was seen in seven of 15 (47%) patients who were progressing before study entry, six of whom were stable at the time of the week 16 CT scan. We were also able to confirm through mandatory pre- and posttherapy tumor biopsies penetration of the ASO into the site of metastasis.


Assuntos
Camptotecina/análogos & derivados , Neoplasias Colorretais/terapia , Fator de Iniciação 4E em Eucariotos/antagonistas & inibidores , Oligonucleotídeos Antissenso/uso terapêutico , Oligorribonucleotídeos/uso terapêutico , Adulto , Idoso , Camptotecina/efeitos adversos , Camptotecina/sangue , Camptotecina/uso terapêutico , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Terapia Combinada , Fator de Iniciação 4E em Eucariotos/genética , Feminino , Células HCT116 , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade , Oligonucleotídeos , Oligonucleotídeos Antissenso/genética , Oligorribonucleotídeos/genética , RNA Mensageiro/sangue , RNA Mensageiro/genética
12.
Br Poult Sci ; 55(6): 715-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25248125

RESUMO

1. Genetic parameters for production and feed efficiency traits in the Orlopp line of turkeys were estimated to determine breeding goals and future potential of the line in a long-term genetic improvement programme. 2. Body weight, egg production and fertility traits were recorded and feed conversion ratio (FCR) was assessed from 16-20 weeks of age. 3. Moderate heritabilities were found for feed intake and body weight gain (0.25 to 0.31). Average FCR was 3.14, with heritability of 0.10. Body weight, breast conformation score and egg production traits showed moderate heritabilities (0.22 to 0.52), while both fertility and hatch of fertile eggs were low (0.04 and 0.09, respectively). 4. Genetic correlations between breast confirmation score, 10- and 18-week body weights were moderate, 0.50 and 0.45, respectively. Average egg weight also showed moderate genetic correlations with 10- and 18-week body weights (0.59 and 0.42).


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/genética , Perus/genética , Animais , Cruzamento , Feminino , Masculino , Característica Quantitativa Herdável , Perus/crescimento & desenvolvimento , Perus/fisiologia
13.
Nature ; 498(7454): 342-5, 2013 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-23783628

RESUMO

Detailed information about the chemical composition and evolution of Mars has been derived principally from the SNC (shergottite-nakhlite-chassignite) meteorites, which are genetically related igneous rocks of Martian origin. They are chemically and texturally similar to terrestrial basalts and cumulates, except that they have higher concentrations of iron and volatile elements such as phosphorus and chlorine and lower concentrations of nickel and other chalcophile (sulphur-loving) elements. Most Martian meteorites have relatively young crystallization ages (1.4 billion years to 180 million years ago) and are considered to be derived from young, lightly cratered volcanic regions, such as the Tharsis plateau. Surface rocks from the Gusev crater analysed by the Spirit rover are much older (about 3.7 billion years old) and exhibit marked compositional differences from the meteorites. Although also basaltic in composition, the surface rocks are richer in nickel and sulphur and have lower manganese/iron ratios than the meteorites. This has led to doubts that Mars can be described adequately using the 'SNC model'. Here we show, however, that the differences between the compositions of meteorites and surface rocks can be explained by differences in the oxygen fugacity during melting of the same sulphur-rich mantle. This ties the sources of Martian meteorites to those of the surface rocks through an early (>3.7 billion years ago) oxidation of the uppermost mantle that had less influence on the deeper regions, which produce the more recent volcanic rocks.

14.
Curr Oncol ; 20(3): e274-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23737698

RESUMO

Radiofrequency ablation (rfa) is a standard treatment for small, unresectable hepatocellular carcinomas (hccs). However, rfa for larger tumours is less successful, and intravenous lyso-thermosensitive liposomal doxorubicin during rfa is one technique postulated to potentially address that limitation. This drug-plus-device combination therapy was used to completely treat a hcc in a patient who underwent liver transplantation 79 days later.

15.
J Anim Sci ; 90(10): 3410-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22665648

RESUMO

Ultrasound measurements of muscle depth were analyzed to determine if these traits could be used to increase the rate of genetic gain in breast meat yield (BMY). Two measurements of breast depth, one taken horizontally across both breast lobes and one parallel to the keel, were captured using ultrasound. Heritabilities of muscle depth traits ranged from 0.35 to 0.70. These values were greater than heritabilities of conformation scores, which ranged from 0.25 to 0.47 within sex and line. The ultrasound traits also showed strong genetic correlations to BMY, ranging from 0.43 to 0.75, indicating that selection, using ultrasound depth as a correlated information source, could result in improved BMY. Including each ultrasound trait in a linear regression model predicting BMY increased the proportion of variation explained by the models by 0.08 to 0.17, relative to using conformation score as the only in vivo estimate. Based on results from a simulated turkey breeding program with selection pressure only on BMY, the ultrasound measures could increase the accuracy of a selection index for BMY by 0.02 to 0.16. As a result, ultrasound technology has the potential to improve the rate of genetic gain in BMY in a breeding program.


Assuntos
Cruzamento/métodos , Carne , Músculos Peitorais/anatomia & histologia , Perus/anatomia & histologia , Perus/genética , Animais , Feminino , Modelos Lineares , Masculino , Modelos Genéticos , Músculos Peitorais/diagnóstico por imagem , Fenótipo , Ultrassonografia
16.
Poult Sci ; 90(11): 2479-86, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22010232

RESUMO

Genetic parameters for production, survival, and structural fitness traits recorded in pedigreed turkey sire and dam parental lines from a nucleus breeding program were estimated with multiple-trait animal models. Survival and conformation traits were scored in binary terms of health, where 0 = died or affected, and 1 = survived or healthy. Walking ability at 20 wk was subjectively scored from 1 (poor) to 6 (excellent). Body weights and egg production displayed moderate heritability (h(2) = 0.18 to 0.35). Early survival (to 3 wk) displayed low heritability (h(2) = 0.02 and 0.04 for the dam and sire lines, respectively). Late survival (3 to 23 wk) and longevity (age at death or cull) had low to moderate heritability (h(2) = 0.12 to 0.14). Walking ability had moderate heritability (h(2) = 0.26, 0.25). Leg structure health displayed low heritability (h(2) = 0.08), as did hip structure, foot, and skin health (h(2) ≤ 0.02). Crop health displayed moderate heritability (h(2) = 0.12). Walking ability, hip and leg structures, footpad, and breast skin health had negative genetic correlations with BW (r(G) = -0.50 to -0.23). Egg production had moderate positive genetic correlation with late survival (r(G) = 0.61). Genetic correlations between early and late survival were close to zero (r(G) = 0.10 and 0.03 for the dam and sire lines, respectively). Walking ability had high positive genetic correlations with late survival, longevity, hip structure, and leg structure in both lines (r(G) = 0.51 to 0.91). These genetic parameters indicate that unchecked selection for growth could decrease survival, walking ability, and hip, leg, footpad, and skin health in turkeys. However, index selection should be effective at improving fitness, survival, and growth simultaneously in commercial turkey lines. Walking ability should be a good indicator trait for selection to improve overall late survival and hip and leg health in turkeys.


Assuntos
Longevidade/genética , Perus/genética , Perus/fisiologia , Animais , Cruzamento , Caminhada
17.
Nature ; 467(7319): E6-7, 2010 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-20981045

RESUMO

It has long been thought that the Earth had a protracted and complex history of volatile accretion and loss. Albarède paints a different picture, proposing that the Earth first formed as a dry planet which, like the Moon, was devoid of volatile constituents. He suggests that the Earth's complement of volatile elements was only established later, by the addition of a small veneer of volatile-rich material at ∼100 Myr (here and elsewhere, ages are relative to the origin of the Solar System). Here we argue that the Earth's mass balance of moderately volatile elements is inconsistent with Albarède's hypothesis but is well explained by the standard model of accretion from partially volatile-depleted material, accompanied by core formation.

18.
J Anim Sci ; 88(6): 1957-66, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20190178

RESUMO

Genotype x environment (GxE) interactions can reduce the accuracy of a model to predict the performance of an animal and have an undesirable influence if not accounted for when estimating breeding values. Consequently, identification of these GxE is necessary when considering a turkey breeding program. Reranking based on the genetic prediction of turkey egg production, fertility, and hatchability in different seasons was indicative of a potential GxE interaction. Quantification of the GxE interactions was based on the genetic correlation estimated when traits were expressed in different seasons. Egg production was expressed as the percentage of days with an egg produced; fertility represented the proportion of hatched eggs that contained a fertile embryo; and hatchability was defined as the percentage of fertile eggs that produced a live bird. Variance components and heritability for egg production, fertility, and hatchability were estimated using ASReml. The heritability (h(2)) of egg production was calculated to be 0.32 for both lines with the phenotypic and genetic variance, 141.3 and 45.58 (percent days with egg produced)(2) and 118.3 and 38.35 (percent days with egg produced)(2) for female and male lines, respectively. The h(2) estimates for fertility were 0.08 in both lines with and of 293.3%(2) and 24.03%(2), and 576.9%(2) and 48.43%(2) for female and male lines, respectively. The hatchability h(2), and estimates were 0.09, 267.1%(2), and 24.44%(2), respectively, for the female line and 0.15, 582.2%(2), and 90.01%(2) for the male line, respectively. Based on an animal model, the variance components were used to calculate estimated breeding values for each trait. The annual fluctuation in estimated breeding values resulted in the need to evaluate egg number, fertility, and hatchability as 2 traits, summer and winter lay. The correlation between the 2 traits was less than unity (female line: r(egg production) = 0.76, r(fertility) = -0.20, r(hatchability) = 0.75 and male line: r(egg production) = 0.86, r(fertility) = 0.19, r(hatchability) = 0.68) suggesting a GxE interaction, and animals will significantly rerank in genetic predictions for these reproductive phenotypes in different seasons of lay. Egg production, fertility, and hatchability in turkeys could be considered as 2 distinct traits in an animal model based on season of lay.


Assuntos
Modelos Genéticos , Oviposição/fisiologia , Característica Quantitativa Herdável , Perus/fisiologia , Animais , Ovos , Feminino , Genótipo , Masculino , Oviposição/genética , Estações do Ano , Perus/genética
19.
Exp Oncol ; 31(2): 106-14, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19550401

RESUMO

AIM: To evaluate the feasibility of fusion of morphologic and functional imaging modalities to facilitate treatment planning, probe placement, probe re-positioning, and early detection of residual disease following radiofrequency ablation (RFA) of cancer. METHODS: Multi-modality datasets were separately acquired that included functional (FDG-PET and DCE-MRI) and standard morphologic studies (CT and MRI). Different combinations of imaging modalities were registered and fused prior to, during, and following percutaneous image-guided tumor ablation with radiofrequency. Different algorithms and visualization tools were evaluated for both intra-modality and inter-modality image registration using the software MIPAV (Medical Image Processing, Analysis and Visualization). Semi-automated and automated registration algorithms were used on a standard PC workstation: 1) landmark-based least-squares rigid registration, 2) landmark-based thin-plate spline elastic registration, and 3) automatic voxel-similarity, affine registration. RESULTS: Intra- and inter-modality image fusion were successfully performed prior to, during and after RFA procedures. Fusion of morphologic and functional images provided a useful view of the spatial relationship of lesion structure and functional significance. Fused axial images and segmented three-dimensional surface models were used for treatment planning and post-RFA evaluation, to assess potential for optimizing needle placement during procedures. CONCLUSION: Fusion of morphologic and functional images is feasible before, during and after radiofrequency ablation of tumors in abdominal organs. For routine use, the semi-automated registration algorithms may be most practical. Image fusion may facilitate interventional procedures like RFA and should be further evaluated.


Assuntos
Ablação por Cateter , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Neoplasias/terapia , Tomografia por Emissão de Pósitrons , Terapia Assistida por Computador/métodos , Algoritmos , Humanos , Software , Tomografia Computadorizada por Raios X
20.
Diabetologia ; 52(7): 1369-80, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19418039

RESUMO

AIMS/HYPOTHESIS: We measured serum C-peptide (at least 0.167 nmol/l) in 54 of 141 (38%) patients with chronic type 1 diabetes and sought factors that might differentiate those with detectable C-peptide from those without it. Finding no differences, and in view of the persistent anti-beta cell autoimmunity in such patients, we speculated that the immunosuppression (to weaken autoimmune attack) and euglycaemia accompanying transplant-based treatments of type 1 diabetes might promote recovery of native pancreatic beta cell function. METHODS: We performed arginine stimulation tests in three islet transplant and four whole-pancreas transplant recipients, and measured stimulated C-peptide in select venous sampling sites. On the basis of each sampling site's C-peptide concentration and kinetics, we differentiated insulin secreted from the individual's native pancreatic beta cells and that secreted from allografted beta cells. RESULTS: Selective venous sampling demonstrated that despite long-standing type 1 diabetes, all seven beta cell allograft recipients displayed evidence that their native pancreas secreted C-peptide. Yet even if chronic immunosuppression coupled with near normal glycaemia did improve native pancreatic C-peptide production, the magnitude of the effect was quite small. CONCLUSIONS/INTERPRETATION: Some native pancreatic beta cell function persists even years after disease onset in most type 1 diabetic patients. However, if prolonged euglycaemia plus anti-rejection immunosuppressive therapy improves native pancreatic insulin production, the effect in our participants was small. We may have underestimated pancreatic regenerative capacity by studying only a limited number of participants or by creating conditions (e.g. high circulating insulin concentrations or immunosuppressive agents toxic to beta cells) that impair beta cell function.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 1 , Imunossupressores/uso terapêutico , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/transplante , Transplante das Ilhotas Pancreáticas , Adulto , Biomarcadores/sangue , Peptídeo C/sangue , Peptídeo C/metabolismo , Doença Crônica , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/cirurgia , Feminino , Veias Hepáticas , Humanos , Insulina/sangue , Insulina/metabolismo , Secreção de Insulina , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Transplante de Pâncreas , Veia Porta , Regeneração/fisiologia , Transplante Homólogo
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