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1.
Polymers (Basel) ; 14(19)2022 Oct 04.
Article in English | MEDLINE | ID: mdl-36236120

ABSTRACT

In this proof-of-concept study, we aim to produce a polyurethane (PU)-based composite that can reduce the amount of viable SARS-CoV-2 virus in contact with the surface of the polymeric film without further interventions such as manual cleaning. Current protocols for maintaining the hygiene of commonly used touchpoints (door handles, light switches, shop counters) typically rely on repeated washing with antimicrobial products. Since the start of the SARS-CoV-2 pandemic, frequent and costly surface sanitization by workers has become standard procedure in many public areas. Therefore, materials that can be retrofitted to touchpoints, yet inhibit pathogen growth for extended time periods are an important target. Herein, we design and synthesise the PU using a one-pot synthetic procedure on a multigram scale from commercial starting materials. The PU forms a robust composite thin film when loaded with 10 wt% silver nanoparticles (AgNPs). The addition of AgNPs increases the ultimate tensile strength, modules of toughness and modulus of elasticity at the cost of a reduced elongation at break when compared to the pristine PU. Comparative biological testing was carried out by the addition of pseudotyped virus (PV) bearing the SARS-CoV-2 beta (B.1.351) VOC spike protein onto the film surfaces of either the pristine PU or the PU nanocomposite. After 24 h without further human intervention the nanocomposite reduced the amount of viable virus by 67% (p = 0.0012) compared to the pristine PU treated under the same conditions. The significance of this reduction in viable virus load caused by our nanocomposite is that PUs form the basis of many commercial paints and coatings. Therefore, we envisage that this work will provide the basis for further progress towards producing a retrofittable surface that can be applied to a wide variety of common touchpoints.

2.
Acta Obstet Gynecol Scand ; 100(1): 170-177, 2021 01.
Article in English | MEDLINE | ID: mdl-32862427

ABSTRACT

INTRODUCTION: Umbilical cord prolapse is a major obstetric emergency associated with significant perinatal complications. However, there is no consensus on the optimal decision-to-delivery interval, as many previous studies have shown poor correlation between the interval and umbilical cord arterial blood gas or perinatal outcomes. We aim to investigate whether bradycardia-to-delivery or decision-to-delivery interval was related to poor cord arterial pH or adverse perinatal outcome in umbilical cord prolapse. MATERIAL AND METHODS: This was a retrospective study conducted at a university tertiary obstetric unit in Hong Kong. All women with singleton pregnancy complicated by cord prolapse during labor between 1995 and 2018 were included. Women were categorized into three groups. Group 1: persistent bradycardia; Group 2: any type of decelerations without bradycardia; and Group 3: normal fetal heart rate. The main outcome was cord arterial blood gas results of the newborns in different groups. Maternal demographic data and perinatal outcomes were reviewed. Correlation analysis between cord arterial blood gas result and time intervals including bradycardia-to-delivery, deceleration-to-delivery, and decision-to-delivery were performed for the different groups with Spearman test. RESULTS: There were 34, 30, and 50 women in Groups 1, 2, and 3, respectively. Cord arterial pH and base excess did not correlate with decision-to-delivery interval in any of the groups, but they were inversely correlated with bradycardia-to-delivery interval in Group 1 (Spearman's ρ = -.349; P = .043 and Spearman's ρ = -.558; P = .001, respectively). The cord arterial pH drops at 0.009 per minute with bradycardia-to-delivery interval in Group 1 (95% CI 0.0180-0.0003). The risk of significant acidosis (pH < 7) was 80% when bradycardia-to-delivery interval was >20 minutes, and 17.2% when the interval was <20 minutes. CONCLUSIONS: There is significant correlation between bradycardia-to-delivery interval and cord arterial pH in umbilical cord prolapse with fetal bradycardia but not in cases with decelerations or normal heart rate. The drop of cord arterial pH is rapid and urgent delivery is essential in such situations.


Subject(s)
Bradycardia/diagnosis , Bradycardia/etiology , Fetal Diseases/diagnosis , Fetal Diseases/etiology , Obstetric Labor Complications/diagnosis , Umbilical Cord/pathology , Adult , Blood Gas Analysis , Female , Hong Kong , Humans , Hydrogen-Ion Concentration , Infant, Newborn , Pregnancy , Pregnancy Outcome , Prolapse , Retrospective Studies
4.
Bone Marrow Transplant ; 55(5): 955-964, 2020 05.
Article in English | MEDLINE | ID: mdl-31768008

ABSTRACT

To optimize voriconazole dosing in pediatric hematopoietic cell transplantation (HCT), we conducted a phase I study with a modified 3 + 3 dose-escalation followed by an expansion cohort at the maximum tolerated, minimum efficacious dose (MTD/MED). Patients ≤21 years who required voriconazole for prevention or treatment of an invasive fungal infection were assigned to three age groups. Of the 59 evaluable patients, 13 were <2 years, 23 were 2-11, and 23 were 12-21. Therapeutic serum voriconazole troughs (1.5-5 µg/mL) drawn at 7 days after initiation determined efficacy. The MTD/MED was 12 mg/kg/dose q12 h × 2 loading doses, then 10 mg/kg/dose q12 h in patients <2, and was 10 mg/kg/dose q12 h in patients 2-11. The 12-21 age group had no dose-limiting toxicity at 8 mg/kg/dose q12 h; however, the MED was not reached. Drug-related AEs ≥grade 3 included increased bilirubin, transaminases, and creatinine, all occurring in <10%. There was no significant association between supra-therapeutic troughs and AEs. Five of 17 patients who had supra-therapeutic troughs (29%) had an AE, compared to 8 of 42 who did not (19%, p = 0.38). Observational population pharmacokinetic analysis demonstrated that inter-individual variability on voriconazole clearance was >100% CV, and clearance increased with age.


Subject(s)
Hematopoietic Stem Cell Transplantation , Invasive Fungal Infections , Administration, Intravenous , Antifungal Agents , Child , Humans , Invasive Fungal Infections/drug therapy , Voriconazole
5.
Chest ; 156(1): 80-91, 2019 07.
Article in English | MEDLINE | ID: mdl-31034818

ABSTRACT

BACKGROUND: Pulmonary rehabilitation (PR) improves exercise capacity and quality of life in people with COPD; however, its effect on anxiety and depression symptoms is less clear. Existing data are difficult to apply to clinical PR because of diverse interventions and comparators. This review evaluated the effectiveness of PR on anxiety and depression symptoms in people with COPD. METHODS: A systematic review and meta-analysis (PROSPERO CRD42018094172) was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines on randomized controlled trials comparing PR (≥ 4 weeks' duration) with usual care. Four electronic databases were searched to February 2018 using terms related to COPD, PR, anxiety, and depression. Data were extracted by two assessors using standardized templates. Study quality was appraised via the PEDro scale, and evidence was rated according to the Grading of Recommendations Assessment, Development and Evaluation. Data were analyzed in RevMan 5.3, with pooled effect estimates reported as standardized mean differences (SMDs). The effect of the program duration (≤ 8 vs > 8 weeks) was explored via subgroup analysis. RESULTS: Eleven studies comprising 734 participants (median PEDro score, 4/10) were included. Compared with usual care, PR conferred significant benefits of a moderate magnitude for anxiety symptoms (SMD, -0.53; 95% CI, -0.82 to -0.23) and large magnitude for depression symptoms (SMD, -0.70; 95% CI, -0.87 to -0.53). The certainty of evidence for each outcome was moderate. Effects were not moderated by program duration. CONCLUSIONS: PR confers significant, clinically relevant benefits on anxiety and depression symptoms. Because further studies involving no treatment control groups are not indicated, these robust estimates of treatment effects are likely to endure.


Subject(s)
Anxiety Disorders/prevention & control , Depressive Disorder/prevention & control , Pulmonary Disease, Chronic Obstructive/rehabilitation , Humans
6.
Clin Cancer Res ; 25(2): 544-551, 2019 01 15.
Article in English | MEDLINE | ID: mdl-30093451

ABSTRACT

PURPOSE: Thyroid cancer is frequently difficult to diagnose due to an overlap of cytologic features between malignant and benign nodules. This overlap leads to unnecessary removal of the thyroid in patients without cancer. While providing some improvement over cytopathologic diagnostics, molecular methods frequently fail to provide a correct diagnosis for thyroid nodules. These approaches are based on the difference between cancer and adjacent thyroid tissue and assume that adjacent tissues are the same as benign nodules. However, in contrast to adjacent tissues, benign thyroid nodules can contain genetic alterations that can be found in cancer.Experimental Design: For the development of a new molecular diagnostic test for thyroid cancer, we evaluated DNA methylation in 109 thyroid tissues by using genome-wide single-base resolution DNA methylation analysis. The test was validated in a retrospective cohort containing 65 thyroid nodules. RESULTS: By conducting reduced representation bisulfite sequencing in 109 thyroid specimens, we found significant differences between adjacent tissue, benign nodules, and cancer. These tissue-specific signatures are strongly linked to active enhancers and cancer-associated genes. Based on these signatures, we developed a new epigenetic approach for thyroid diagnostics. According to the validation cohort, our test has an estimated specificity of 97% [95% confidence interval (CI), 81-100], sensitivity of 100% (95% CI, 87-100), positive predictive value of 97% (95% CI, 83-100), and negative predictive value of 100% (95% CI, 86-100). CONCLUSIONS: These data show that epigenetic testing can provide outstanding diagnostic accuracy for thyroid nodules.See related commentary by Mitmaker et al., p. 457.


Subject(s)
DNA Methylation , Epigenesis, Genetic , Thyroid Nodule/diagnosis , Thyroid Nodule/genetics , Transcriptome , Biomarkers, Tumor , Biopsy, Fine-Needle , Diagnosis, Differential , Epigenomics/methods , Humans , Mutation , Organ Specificity , Polymerase Chain Reaction , Protein Array Analysis , Sensitivity and Specificity , Thyroid Neoplasms/diagnosis , Thyroid Neoplasms/genetics
7.
Qual Life Res ; 26(9): 2321-2331, 2017 09.
Article in English | MEDLINE | ID: mdl-28421384

ABSTRACT

PURPOSE: This study was to evaluate the efficacy of a complementary Chinese treatment modality Guolin-Qigong (GLQG) for patients with breast cancer on the body-mind health. METHODS: A randomized controlled clinical trial was conducted among 158 women with breast cancer. Subjects were randomized to receive GLQG (test group) versus a physical stretching program (control group) following conventional treatment for breast cancer. GLQG and stretching interventions were performed twice a week over 24 weeks. The primary outcome was the change in quality of life (QoL). Secondary outcome measures included anxiety, depression, and clinical indicators. All participants were assessed at four time-points, at the beginning of the study (T1), after 12 weeks of the intervention (T2), immediately after 24-week intervention (T3), and at 48-week follow-up visit (T4). RESULTS: Improvements in QoL were evident in both groups but the test group fared better than the control group at the 12th week (P < 0.01) and particularly in emotional well-being (P < 0.01) and breast cancer-specific well-being (P < 0.001). The test group showed an improvement in anxiety levels (P < 0.01), whereas the control group showed improvements in depression (P < 0.05) but there was no significant difference between groups (P > 0.05). Both groups showed improvements in immunological function and the test group fared better than the control in TNF-α levels (P < 0.05). The results in subjects who practiced more than 4 times and 6 h per week were similar to that of all subjects; however, the improvement in anxiety in the GLQG group was more obvious. There are positive correlations between QoL and anxiety and depression. CONCLUSIONS: Both GLQG and physical stretching are beneficial during recovery following breast cancer. GLQC was more effective in terms of Qol improvements than physical stretching. Both programs brought improvements in anxiety or depression but had were comparable. GLQC group had a greater effect on immunological function than physical exercise.


Subject(s)
Breast Neoplasms/psychology , Qigong/methods , Quality of Life/psychology , Female , Humans , Middle Aged
9.
Poult Sci ; 92(4): 923-9, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23472015

ABSTRACT

A multiple trait linear-threshold model was used to analyze data for BW, residual feed intake, breast meat yield (BMY), conformation score (CS), area (AR), tibial dyschondroplasia, valgus, varus, and rotated tibia. Leg soundness traits were considered as binary responses. At the liability scale, the model included the fixed effects of flock-week of hatch, and sex of the bird and the genetic additive effect, and the error terms as random. The random maternal effect was included in the model only for BW. A full Bayesian implementation of the model was straightforward even though large number of traits and missing records were present. As expected, binary traits have the lowest heritability. Heritability ranged from 0.12 for tibial dyschondroplasia to 0.44 for BMY. Genetic correlations between BW and conformation traits were moderate to high. Residual feed intake was negatively correlated with BW (-0.15), AR (-0.13), BMY (-0.04), and CS (-0.12). Genetic correlation between leg soundness traits were generally low and negative with the exception of the correlation between valgus and varus (-0.70) and between varus and rotated tibia (-0.39). Genetic correlations between BW, BMY, CS, and AR with leg soundness traits were in general negative and low in magnitude. Thus, selecting for improved leg soundness will have minimal effect on BW and carcass traits. Furthermore, genetic improvement in residual feed intake will result in improvements in carcass traits. Simultaneous genetic improvement in leg soundness and innovative husbandry practices should improve broiler welfare without significant adverse effects on production efficiency.


Subject(s)
Chickens/growth & development , Chickens/genetics , Poultry Diseases/pathology , Poultry Diseases/physiopathology , Animal Nutritional Physiological Phenomena , Animals , Bayes Theorem , Body Weight , Female , Hindlimb/pathology , Hindlimb/physiopathology , Linear Models , Male , Meat/standards , Models, Biological , Pectoralis Muscles/growth & development
10.
Mol Ther ; 21(2): 324-37, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23299800

ABSTRACT

Genotoxicity models are extremely important to assess retroviral vector biosafety before gene therapy. We have developed an in utero model that demonstrates that hepatocellular carcinoma (HCC) development is restricted to mice receiving nonprimate (np) lentiviral vectors (LV) and does not occur when a primate (p) LV is used regardless of woodchuck post-translation regulatory element (WPRE) mutations to prevent truncated X gene expression. Analysis of 839 npLV and 244 pLV integrations in the liver genomes of vector-treated mice revealed clear differences between vector insertions in gene dense regions and highly expressed genes, suggestive of vector preference for insertion or clonal outgrowth. In npLV-associated clonal tumors, 56% of insertions occurred in oncogenes or genes associated with oncogenesis or tumor suppression and surprisingly, most genes examined (11/12) had reduced expression as compared with control livers and tumors. Two examples of vector-inserted genes were the Park 7 oncogene and Uvrag tumor suppressor gene. Both these genes and their known interactive partners had differential expression profiles. Interactive partners were assigned to networks specific to liver disease and HCC via ingenuity pathway analysis. The fetal mouse model not only exposes the genotoxic potential of vectors intended for gene therapy but can also reveal genes associated with liver oncogenesis.


Subject(s)
Cell Transformation, Neoplastic/genetics , DNA Damage , Fetus/pathology , Genetic Therapy/adverse effects , Infectious Anemia Virus, Equine/genetics , Liver/pathology , Animals , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/therapy , Disease Models, Animal , Gene Expression , Gene Expression Profiling , Gene Transfer Techniques , Genetic Therapy/methods , Genetic Vectors , Genome , HIV/genetics , Immunohistochemistry , Liver Neoplasms/pathology , Liver Neoplasms/therapy , Mice , Mutagenesis , Mutagenesis, Insertional , Mutation , Real-Time Polymerase Chain Reaction
11.
Poult Sci ; 91(10): 2576-87, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22991544

ABSTRACT

Global RNA expression in breast muscle obtained from a male broiler line phenotyped for high or low feed efficiency (FE) was investigated using microarray analysis. Microarray procedures and validation were reported previously. By using an overlay function of a software program (Ingenuity Pathway Analysis, IPA) in which canonical pathways are projected onto a set of genes, a subset of 27 differentially expressed focus genes were identified. Focus genes that were upregulated in the high FE phenotype were associated with important signal transduction pathways (Jnk, G-coupled, and retinoic acid) or in sensing cell energy status and stimulating energy production that would likely enhance growth and development of muscle tissue. In contrast, focus genes that were upregulated in the low FE muscle phenotype were associated with cytoskeletal architecture (e.g., actin-myosin filaments), fatty acid oxidation, growth factors, or ones that would likely be induced in response to oxidative stress. The results of this study provide additional information on gene expression and the cellular basis of feed efficiency in broilers.


Subject(s)
Chickens/genetics , Chickens/metabolism , Energy Metabolism/genetics , Gene Expression Profiling/veterinary , Muscle, Skeletal/metabolism , Animals , Energy Metabolism/physiology , Gene Expression Regulation/physiology , Male , Muscle Proteins/genetics , Muscle Proteins/metabolism , Phenotype , Protein Array Analysis/veterinary , RNA/genetics , RNA/metabolism
12.
Poult Sci ; 90(11): 2535-47, 2011 Nov.
Article in English | MEDLINE | ID: mdl-22010239

ABSTRACT

Global RNA expression in breast muscle obtained from a male broiler line phenotyped for high or low feed efficiency (FE) was investigated. Pooled RNA samples (n = 6/phenotype) labeled with cyanine 3 or cyanine 5 fluorescent dyes to generate cRNA probes were hybridized on a 4 × 44K chicken oligo microarray. Local polynomial regression normalization was applied to background-corrected red and green intensities with a moderated t-statistic. Corresponding P-values were computed and adjusted for multiple testing by false discovery rate to identify differentially expressed genes. Microarray validation was carried out by comparing findings with quantitative reverse-transcription PCR. A 1.3-fold difference in gene expression was set as a cutoff value, which encompassed 20% (782 of 4,011) of the total number of genes that were differentially expressed between FE phenotypes. Using an online software program (Ingenuity Pathway Analysis), the top 10 upregulated genes identified by Ingenuity Pathway Analysis in the high-FE group were generally associated with anabolic processes. In contrast, 7 of the top 10 downregulated genes in the high-FE phenotype (upregulated in the low-FE phenotype) were associated with muscle fiber development, muscle function, and cytoskeletal organization, with the remaining 3 genes associated with self-recognition or stress-responding genes. The results from this study focusing on only the top differentially expressed genes suggest that the high-FE broiler phenotype is derived from the upregulation of genes associated with anabolic processes as well as a downregulation of genes associated with muscle fiber development, muscle function, cytoskeletal organization, and stress response.


Subject(s)
Chickens/genetics , Chickens/metabolism , Gene Expression Regulation/physiology , Muscle, Skeletal/metabolism , Protein Array Analysis/veterinary , Animals , Gene Expression Profiling , Male , Muscle Proteins/genetics , Muscle Proteins/metabolism , Reverse Transcriptase Polymerase Chain Reaction
13.
J Anim Sci ; 89(1): 23-8, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20889689

ABSTRACT

Data of broiler chickens for 2 pure lines across 3 generations were used for genomic evaluation. A complete population (full data set; FDS) consisted of 183,784 and 164,246 broilers for the 2 lines. The genotyped subsets (SUB) consisted of 3,284 and 3,098 broilers with 57,636 SNP. Genotyped animals were preselected based on more than 20 traits with different index applied to each line. Three traits were analyzed: BW at 6 wk (BW6), ultrasound measurement of breast meat (BM), and leg score (LS) coded 1 = no and 2 = yes for leg defect. Some phenotypes were missing for BM. The training population consisted of the first 2 generations including all animals in FDS or only genotyped animals in SUB. The validation data set contained only genotyped animals in the third generation. Genetic evaluations were performed using 3 approaches: 1) phenotypic BLUP, 2) extending BLUP methodologies to utilize pedigree and genomic information in a single step (ssGBLUP), and 3) Bayes A. Whereas BLUP and ssGBLUP utilized all phenotypic data, Bayes A could use only those of the genotyped subset. Heritabilities were 0.17 to 0.20 for BW6, 0.30 to 0.35 for BM, and 0.09 to 0.11 for LS. The average accuracies of the validation population with BLUP for BW6, BM, and LS were 0.46, 0.30, and <0 with SUB and 0.51, 0.34, and 0.28 with FDS. With ssGBLUP, those accuracies were 0.60, 0.34, and 0.06 with SUB and 0.61, 0.40, and 0.37 with FDS, respectively. With Bayes A, the accuracies were 0.60, 0.36, and 0.09 with SUB. With SUB, Bayes A and ssGBLUP had similar accuracies. For traits of high heritability, the accuracy of Bayes A/SUB and ssGBLUP/FDS were similar, and up to 50% better than BLUP/FDS. However, with low heritability, ssGBLUP/FDS was 4 to 6 times more accurate than Bayes A/SUB and 50% better than BLUP/FDS. An optimal genomic evaluation would be multi-trait and involve all traits and records on which selection is based.


Subject(s)
Chickens/genetics , Genome , Genotype , Pedigree , Animals , Female , Genetic Markers , Male , Models, Genetic
14.
Poult Sci ; 89(2): 349-52, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20075289

ABSTRACT

The objective of this study was to assess the expression of mitochondrial proteins and oxidized proteins in heart muscle homogenate obtained from male broilers exhibiting either high or low feed efficiency (G:F) phenotypes. Tissue homogenate was prepared from ventricular tissue obtained from broilers with high (0.80+/-0.01, n=8) and low (0.62+/-0.02, n=8) FE. The levels of specific immunoreactive proteins and oxidized proteins (carbonyls) were determined using Western blot analysis. The expression of 6 electron transport chain proteins [complex II, 70S subunit (CII 70S); iron-sulfur-containing protein (ISP), cytochrome b (Cyt b), cytochrome (Cyt c1) (of complex III); and cytochrome oxidase subunit II (COX II) (of complex IV)] and adenine nucleotide translocator 1 (ANT1) were higher in low feed efficiency heart mitochondria, but 1 protein [NAD subunit 6c (NAD6c) (complex I)] was higher in high feed efficiency birds. Protein carbonyl levels, indicative of oxidized proteins, were higher in heart tissue of low compared with high feed efficiency broilers.


Subject(s)
Chickens/genetics , Chickens/physiology , Gene Expression Regulation/physiology , Mitochondria, Heart/metabolism , Myocardium/metabolism , Proteins/metabolism , Animal Feed , Animals , Diet/veterinary , Energy Metabolism , Male , Oxidation-Reduction , Weight Gain
15.
Poult Sci ; 88(8): 1683-93, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19590084

ABSTRACT

Studies were conducted to assess proton leak kinetics (proton conductance) in breast muscle mitochondria isolated from broiler breeder males within a single genetic line exhibiting either high (HFE) or low (LFE) feed efficiency. Proton leak kinetics were determined by simultaneously measuring mitochondrial membrane potential and state 2 (resting) respiration rate in breast muscle mitochondria as succinate oxidation was progressively decreased by malonate. Control proton conductance was similar in HFE and LFE mitochondria and decreased to a similar extent in both groups in response to BSA. Although treatment of mitochondria with Glu or guanosine diphosphate had no effect, retinal increased and carboxyatractylate alone or in combination with Glu decreased proton conductance relative to control proton conductance in both HFE and LFE mitochondria. After treatment with either guanosine diphosphate or carboxyatractylate alone, proton conductance was lower in HFE compared with LFE mitochondria. With the exception of BSA, proton conductance in HFE mitochondria after the various chemical treatments was either less than or equal to, and never greater than, proton conductance in the LFE mitochondria. The results suggest that there are subtle differences in membrane characteristics (e.g., lipids, integral membrane proteins) that affect proton conductance in broiler muscle mitochondria that may in turn play a role in the phenotypic expression of feed efficiency.


Subject(s)
Chickens/growth & development , Chickens/genetics , Membrane Potential, Mitochondrial/physiology , Protons , Animal Nutritional Physiological Phenomena/genetics , Animals , Energy Metabolism , Kinetics , Male , Muscle, Skeletal/metabolism , Oxygen Consumption/physiology
16.
Article in English | MEDLINE | ID: mdl-17409002

ABSTRACT

Increased hydrogen peroxide (H2O2) production was observed in duodenal mitochondria obtained from broiler chickens with low feed efficiency (FE). As a decrease in mitochondrial membrane potential (Deltapsi(m)) due to mild uncoupling of oxidative phosphorylation reduces reactive oxygen species production, this study was conducted to evaluate the effect of uncoupling on Deltapsi(m) and H2O2 production in duodenal mitochondria isolated from broilers with low (0.48+/-0.02) and high (0.68+/-0.01) FE. Membrane potential and H2O2 production were measured fluorometrically and in the presence of different levels of an uncoupler, carbonylcyanide-p-trifluoromethoxyphenylhydrazone (FCCP). The Deltapsi(m) was higher (P

Subject(s)
Chickens/metabolism , Duodenum/metabolism , Feeding Behavior , Hydrogen Peroxide/metabolism , Membrane Potential, Mitochondrial , Mitochondria/metabolism , Animals , Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone/pharmacology , Cell Respiration/drug effects , Duodenum/drug effects , Electron Transport/drug effects , Feeding Behavior/drug effects , Male , Membrane Potential, Mitochondrial/drug effects , Mitochondria/drug effects , Superoxide Dismutase/metabolism
17.
Poult Sci ; 86(2): 372-81, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17234853

ABSTRACT

This study was conducted to evaluate messenger RNA (mRNA) expression of genes that are involved in energy metabolism and mitochondrial biogenesis: avian adenine nucleotide translocator (avANT), cytochrome oxidase III (COX III), inducible nitric oxide synthase (iNOS), peroxisome proliferator-activated receptor-gamma (PPAR-gamma), avian PPAR-gamma coactivator-1alpha (avPGC-1alpha), and avian uncoupling protein in breast muscle and duodenum of broilers with low and high feed efficiency (FE). Total RNA was extracted from snap-frozen tissues from male broilers with low (0.55 +/- 0.01) and high (0.72 +/- 0.01) FE (n = 8 per group). Total RNA was reverse-transcribed using oligo(dT), random primers, or both followed by real-time reverse transcription-PCR. Protein oxidation, measured as protein carbonyls, was also evaluated in duodenal mucosa. Protein carbonyls were higher in low FE mucosa in tissue homogenate and mitochondrial fraction. The mRNA expression of iNOS and PPAR-gamma in the duodenum was lower in the low FE broilers, with no differences in avANT, COX III, and avPGC-1alpha. In contrast, expression of avANT and COX III mRNA in breast muscle was lower in low FE broilers with no differences in iNOS, PPAR-gamma, and avPGC-1alpha. The avian uncoupling protein in breast muscle was higher in low FE birds (P = 0.068). These results indicate that there are differences in the expression of mRNA encoding for mitochondrial transcription factors and proteins in breast muscle and duodenal tissue between low and high FE birds. The differences that were observed may also reflect inherent metabolic and gene regulation differences between tissues.


Subject(s)
Chickens/genetics , Chickens/physiology , Digestion/genetics , Digestion/physiology , Duodenum/metabolism , Gene Expression Regulation , Muscle, Skeletal/metabolism , Animal Feed , Animals , Electron Transport Complex IV/genetics , Ion Channels/genetics , Male , Mitochondrial ADP, ATP Translocases/genetics , Mitochondrial Proteins/genetics , PPAR gamma/genetics , RNA, Messenger/metabolism , Uncoupling Protein 1
18.
Poult Sci ; 85(12): 2251-9, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17135683

ABSTRACT

Studies were conducted to investigate relationships between mitochondrial and extramitochondrial protein expression, and protein oxidation in lymphocytes obtained from broilers in which individual feed efficiencies were obtained. Lymphocytes were isolated from male broilers from a single line that were shown to exhibit either low (0.48 +/- 0.02, n = 8) or high (0.68 +/- 0.01, n = 7) feed efficiency (FE). Western blot analysis showed that, compared with lymphocytes from high FE broilers, lymphocytes from low FE broilers exhibited a) higher amounts of oxidized proteins (protein carbonyls), b) lower amounts of 3 mitochondrial proteins [core I, cyt c 1 (complex III), and ATP synthase (complex V)], and c) higher amounts of 2 proteins [30 S (complex II) and COX II (complex IV)]. Two-dimensional gel electrophoresis revealed that the intensities of 25 protein spots from pooled samples of lymphocytes from high and low FE broilers differed by 5-fold or more. Three of these protein spots were picked from the gel and subjected to matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry analysis. One protein spot of ~33 kDa was tentatively identified by MALDI-TOF as a fragment of collapsin-2, a component of semaphorin 3D. The results of this study provide further evidence of increased oxidation associated with low FE and further evidence of differential protein expression associated with the phenotypic expression of feed efficiency.


Subject(s)
Chickens/metabolism , Energy Metabolism/physiology , Gene Expression Regulation/physiology , Lymphocytes/metabolism , Mitochondrial Proteins/metabolism , Weight Gain/physiology , Animal Feed , Animals , Male
19.
Poult Sci ; 84(7): 1010-4, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16050117

ABSTRACT

The objective of the current study was to compare the performances of a longitudinal multipletrait (MT) and cumulative single-trait (ST) best linear unbiased prediction (BLUP) analyses for eggs set (E), percentage fertility (F), and percentage hatched of fertile eggs (H) based on rank correlations of hens and roosters (ROO). Longitudinal data consisted of weekly records, and the ST analysis used cumulative records of the 3 traits. Comparisons were carried out using simulated data, in which true values assigned during the simulation were compared with estimates obtained from MT and ST analyses. Two methods were used to calculate breeding values and ROO effects. Weekly E records equal to zero were assumed as valid records, and missing weekly F and H records were predicted in MT analysis. However, missing F and H were not included in the cumulative record. Weekly E, F, and H records were converted to a cumulative record following a procedure used by a commercial broiler company. Further, ST models were developed to evaluate hens and ROO separately as currently practiced in the industry. There was virtually no difference in hen rank correlations between true and predicted breeding values obtained from MT (0.64) and ST (0.62) analyses for E, thus suggesting that hens would rank similarly when weekly or cumulative data were used for genetic evaluation of E. With ST analysis, rank correlations between true and estimated hen breeding values decreased, compared with MT analysis, by 74 and 75% for F and H, respectively. For F (H), the rank correlation between true and estimated ROO effects were 0.64 (0.67) and 0.17 (0.12) with MT and ST analyses, respectively. The results suggested that longitudinal MT BLUP, which handles missing records, was better at estimating true hen and ROO effects than ST BLUP. Therefore, it was recommended that the MT BLUP method be used for genetic evaluation of hens and ROO for E, F, and H.


Subject(s)
Chickens/genetics , Chickens/physiology , Fertility , Ovum/physiology , Quantitative Trait, Heritable , Animals , Breeding , Female , Male , Selection, Genetic
20.
Poult Sci ; 84(6): 933-41, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15971533

ABSTRACT

Variations in broiler growth and efficiency have been explained in part by differences in mitochondrial function and biochemistry in broilers. To further our knowledge in this regard, 2 experiments were carried out to determine the relationships of a) mitochondrial function and activities of various electron transport chain (ETC) complexes; b) production of H2O2, a reactive oxygen species (ROS), and its association with protein oxidation; and c) mitochondrial protein expression in liver of a single line male broilers with low or high feed efficiency (FE, n = 5 to 8 per group). Mitochondrial function and complex activities were measured polarographically and spectrophotometrically, respectively. H2O2 was measured fluorimetrically, whereas oxidized protein (carbonyls) and specific mitochondrial proteins were analyzed using Western blots. Mitochondrial function (ETC coupling) and activities of ETC complexes (I, II, III, and IV) were higher in high FE compared with low FE broilers. H2O2 and protein carbonyls were higher in the livers of low FE broilers than in high FE broilers. Whereas the expression of 4 immunoreactive proteins [NAD3 (complex I), subunit VII (complex III), cytochrome c oxidase subunits (COX) II, and COX IVb (complex IV)] were higher in low FE liver mitochondria and 2 proteins [subunit 70 (complex II) and a-ATP synthase (complex V)] were higher in high FE birds, there were no differences between groups in the expression of 18 other mitochondrial proteins. In conclusion, increases in oxidative stress in low FE broilers were caused by or may contribute to differences in mitochondrial function (ETC coupling and complex activities) or the differential expression of steady-state levels of some mitochondrial proteins in the liver. Understanding the role of oxidative stress in Low FE broilers will provide clues in understanding the cellular basis of feed efficiency.


Subject(s)
Animal Feed , Chickens/physiology , Mitochondria, Liver/physiology , Mitochondrial Proteins/analysis , Oxidative Stress , Animal Nutritional Physiological Phenomena , Animals , Blotting, Western , Breeding , DNA, Mitochondrial/genetics , Electron Transport , Electrophoresis, Polyacrylamide Gel , Gene Expression , Hydrogen Peroxide/metabolism , Male , Mitochondrial Proteins/chemistry , Mitochondrial Proteins/genetics , Oxidation-Reduction
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